production of high quality australian ginseng
TRANSCRIPT
Production of High Quality Australian Ginseng
A report for the Rural Industries Research and Development Corporation by R. B. H. Wills & D. L. Stuart
December 2001 RIRDC Publication No 01/170 RIRDC Project No: UNC-8A
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© 2001 Rural Industries Research and Development Corporation. All rights reserved. ISBN 0 642 58389 7 ISSN 1440-6845 Production of High Quality Australian Ginseng Publication No. 01/170 Project No: UNC-8A The views expressed and the conclusions reached in this publication are those of the author and not necessarily those of persons consulted. RIRDC shall not be responsible in any way whatsoever to any person who relies in whole or in part on the contents of this report. This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquiries concerning reproduction, contact the Publications Manager on phone 02 6272 3186. Researcher Contact Details Professor Ron Wills Centre for the Advancement of Food Technology & Nutrition The University of Newcastle PO Box 127 OURIMBAH NSW 2308 Phone: (02) 4348 4140 Fax: (02) 4348 4148 Email: [email protected]
RIRDC Contact Details Rural Industries Research and Development Corporation Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6272 4539 Fax: 02 6272 5877 Email: [email protected]. Website: http://www.rirdc.gov.au Published in December 2001 Printed on environmentally friendly paper by Canprint
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Foreword With the rapidly expanding use of medicinal herbs world-wide, Australia has recognised the opportunity to become an international supplier of many medicinal herbs. As a relatively high cost producer nation the economic benefit will come through the cultivation, processing and marketing of high quality products. High quality in medicinal herbs is the presence of optimal levels of those constituents which confer a health benefit to consumers. In order to support development of a high quality medicinal herb industry in Australia, RIRDC has supported a number of projects under its Essential Oils and Plant Extracts Program. This report details a project on American ginseng that examines changes in the levels of the ginsenosides during plant growth, postharvest handling, processing and in marketed-products. The study identifies a range of options available to maximise the level of active constituents in marketed products. The work detailed in the project was conducted with the active support of the Australian Ginseng Growers Association. This project was funded from RIRDC Core Funds which are provided by the Federal Government. This report, a new addition to RIRDC’s diverse range of over 700 research publications, forms part of our Essential Oils R&D program, which aims to support the growth of a profitable and sustainable essential oils and natural plant extracts industry in Australia. Most of our publications are available for viewing, downloading or purchasing online through our website: • downloads at www.rirdc.gov.au/reports/Index.htm • purchases at www.rirdc.gov.au/eshop Peter Core Managing Director Rural Industries Research and Development Corporation
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Acknowledgements The authors wish to acknowledge that Ms Xiao-Wei Du performed the laboratory studies which formed part of her PhD program, and Mr Jason van Ritten carried out the grower survey while enrolled in a MSc program, both at the University of Newcastle. We would also like to thank the Australian Ginseng Growers Association (AGGA), and in particular Charlene and Fred Hosemans, and the Committee of AGGA for their generous and active support of research into the quality of American ginseng at the University of Newcastle. Thanks are also given to Dr David Evans, Program Manager, RIRDC for valued suggestions and encouragement during the course of the project and to Dr Krystyna Johnson for her involvement in the grower survey.
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Contents Foreword iii
Acknowledgements.......................................................................................................................... iv
Executive summary ......................................................................................................................... vi
1. Introduction ............................................................................................................................. 1
1.2 Objectives ........................................................................................................................ 2
2. Analysis of ginsenosides .............................................................................................................. 3
2.1 Neutral ginsenosides ........................................................................................................... 3 2.2 Malonyl ginsenosides ......................................................................................................... 5
3. Changes in neutral ginsenosides during plant growth............................................................. 6
3.1 Variation between individual roots ..................................................................................... 6 3.2 Changes in plant parts over a growing season .................................................................... 7
3.2.1 Neutral ginsenosides composition ............................................................................ 7 3.3.2 Concentration of neutral ginsenosides ................................................................... 13 3.2.3 Total amount of neutral ginsenosides..................................................................... 14
3.3 Changes in neutral ginsenosides with root age ................................................................. 14 3.4 Variation in ginsenosides in roots grown at different sites ............................................... 17
4. Processing and storage.............................................................................................................. 18
4.1 Drying temperature ........................................................................................................... 18 4.2 Blanching ...................................................................................................................... 18 4.4 Alcoholic extract............................................................................................................... 22 4.5 Spray Drying..................................................................................................................... 23 4.6 Neutral ginsenosides in commercial products................................................................... 24
5. Farmer survey of growing Practises........................................................................................ 27
5.1 Farm environment ............................................................................................................. 27 5.2 Growing practices ............................................................................................................. 27 5.3 Grower circumstances....................................................................................................... 28
6. Conclusions and recommendations ......................................................................................... 30
6.1 Need for analysis of active constituents............................................................................ 30 6.3 Benefit of maximising root size ........................................................................................ 31 6.4 Need for improved postharvest operations ....................................................................... 31 6.5 Quality of retail products .................................................................................................. 32 6.6 Development of the Australian industry ........................................................................... 33
7. References ........................................................................................................................... 34
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Executive summary
American ginseng (Panax quinquefolium) is a medicinal herb native to the temperate regions of North America. It has found considerable usage in north Asia where Asian ginseng (Panax ginseng) has been a traditional medicine for many centuries. The accelerating affluence of many Asian countries coupled with the growing popularity of alternative therapies in the Western world has led to a marked increase in the international trade in both species of ginseng. The growth in ginseng trading has led to the establishment of an Australian industry based on the growing of American ginseng. While the industry is still in its infancy, it has created an umbrella organisation, the Australian Ginseng Growers Association (AGGA), which is promoting a national approach to industry development. Australia is agriculturally well positioned to capture a share of the world market and cropping is now conducted on organic principles in a wide range of regions across the eastern and southern States. If Australia is to become successful at exporting and import substitution, it needs to resolve various marketing and quality issues. As traders and consumers become more sophisticated in their requirements for product quality, and the world crop supply increases to match, or as appears likely to exceed market demand, there will be greater competition in the ginseng market. Countries which have the reputation and ability to consistently supply high quality raw material and processed products will gain preferential access to the higher price market segment, thus maximising the economic return from the crop. The ultimate determinant quality factor in all medicinal herbs, including ginseng, is the concentration of active constituents that impart a health benefit to the human body. While a number of groups of active compounds have been identified, it is widely accepted that the saponins known as ginsenosides, are major active constituents in ginseng. The research studies described in this report used the major ginsenosides of Rg1, Re, Rb1, Rc, Rb2, and Rd as the markers of ginseng quality. The overall aim of the project was to assist the Australian growers to develop a marketing strategy for future Australian-grown American ginseng crops based on quality. The research objectives focused on determining:
• reliable methods for the analysis of ginsenosides, • changes in ginsenosides in plant parts during plant growth and maturation, • effect of postharvest handling and processing operations on ginsenosides, • quality of ginseng products available in retail outlets, and • survey the situation and practices of Australian ginseng farms.
Efficient and reliable quantitative analytical methods for the analysis of both neutral and malonyl ginsenosides in American ginseng were developed using high performance liquid chromatography (HPLC). The importance of neutral ginsenosides is well known but relatively recently recognition of the importance of malonyl ginsenosides due to their potential hydrolysis to neutral ginsenosides has highlighted the need for both malonyl and neutral ginsenosides to be analysed in any quality assurance system established by the industry. In this project, the importance of malonyl ginsenosides was not recognised until after most of the growth trials had been completed and hence data for malonyl ginsenosides was mostly only obtained for the processing and storage trials. The neutral ginsenosides in the various parts of 4-year old American ginseng plants grown in Victoria were determined at seven harvest periods over a whole growing cycle from leaf emergence to dormancy. It was found that ginseng roots contained a similar composition and concentration of neutral ginsenosides as roots grown in North America and Asia and should therefore be as acceptable in medicinal quality for the international market as American ginseng grown in other countries. In addition, the concentration of ginsenosides tended to be at the upper level of the range previously reported for American ginseng. The cultivation of ginseng under a canopy of eucalypt trees has thus appeared not to have a detrimental effect on the accumulation of neutral ginsenosides.
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The concentration of the neutral ginsenosides over the growth period showed little change in the main root and lateral root. The highest concentration of ginsenosides was in the leaf and the hair root and in these plant parts, the concentration significantly increased to a maximum value at the growth stage when green fruit was present. The absolute amount of neutral ginsenosides in plant sections, the amount being a function of plant weight and ginsenosides concentration, showed that the main root and lateral root contained most of the plant ginsenosides due to their high contribution to total plant weight. The hair roots had the highest ginsenosides concentration but contributed only about 5% of the total ginsenosides due to its relatively low weight. However, the leaves when fully developed contained about 25% of the total ginsenosides from a high concentration and weight contribution. The ginseng industry world-wide has traditionally marketed only the main and larger lateral root sections. The findings from this project suggest that utilisation of the leaves and, to a lesser extent, the hair roots, could generate a valuable by-product with beneficial medicinal properties. Commercial utilisation of leaf material would, however, require harvesting of the plant before the leaves started to senesce rather than at the current dormant stage. This would appear feasible since there was no reduction in the concentration of ginsenosides in roots if harvested at an earlier stage of plant development. The pharmacological activity of the two plant sections would appear to be similar as the composition of ginsenosides is not radically different between the leaf and root but this would need further investigation. An additional consideration would be to confirm that early harvesting of the leaf every year did not affect growth of the root. The harvesting of leaves would at least allow some return to growers before the root attained commercial maturity. The determination of ginsenosides in roots of different age grown on a single site and of the same age but grown in different locations showed that for both sets of roots, there was a strong linear relationship between root weight and ginsenosides concentration. The findings suggested that it would be advantageous for the industry to identify growing practices or improved plant nutrition that increase the rate of root growth. The benefits to be gained would not only be an increase in root size but also an increase in ginsenosides concentration. While there was only a limited number of samples in the survey of roots from different farms, the results also suggested that field cultivated material under artificial shade produce a faster growing root and therefore a greater concentration of ginsenosides than forest-grown roots. This relationship needs to be explored further. In the farm survey, the malonyl ginsenosides were also analysed and the data show that in fresh roots the proportion of neutral to malonyl ginsenosides was in the ratio of 3:2. This factor could be useful in estimating the total ginsenosides in roots where the malonyl ginsenosides were not analysed. Since the importance of managing postharvest handling operations in maintaining ginseng quality does not appear to have been extensively studied in other countries, there is an opportunity for Australia to gain a market advantage by retaining ginsenosides in traded products through improving such practices. The project examined the effect on ginsenosides of the drying of fresh root, storage of dried root, steam blanching of fresh root, alcoholic extraction of dried root powder and spray drying of the alcoholic extract. A study was conducted to determine the effect of air temperature on the ginsenosides during the drying of fresh roots in a hot air drier. Increasing the drying temperature was found to cause a loss of malonyl ginsenosides, a small increase in neutral ginsenosides and a loss of total ginsenosides. The drying temperature should therefore be minimised to optimise retention of total ginsenosides. A drying temperature of 55ºC is recommended over lower temperatures due to the reduced drying time with little loss of ginsenosides. Drying at higher temperatures further reduces drying time but with enhanced loss of ginsenosides along with significant tissue browning. While there was no evaluation of other drying technologies such as heat pump, low pressure and freeze drying, it is suggested that these technologies would result in reduced loss of ginsenosides as they employ less heat during drying, but the equipments are much more expensive to purchase and operate.
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Storage of dried ginseng root powder over the temperature range of 5˚ to 30˚C was found to be temperature dependent. There was increasing loss of total ginsenosides with increasing temperature which was associated with an initial conversion of malonyl ginsenosides to the corresponding neutral ginsenosides. Optimum storage for dried material is therefore at low temperatures such as 5˚C where no appreciable loss of ginsenosides occurred over three months. However, it would also seem prudent based on experience with other medicinal herbs, to use packaging that protects the product from absorption of atmospheric moisture and probably also light. Steam blanching is a traditional method to produce the "red ginseng” from Asian ginseng root. No published studies are available to show the change in malonyl and neutral ginsenosides during the blanching of Asian or American ginseng but this study found a similar loss of ginsenosides with increased blanching time as with increased heat loading during drying. At the optimum blanching time of 2 hr which produces an attractive appearance for the red ginseng product, there was a loss of 15% in total ginsenosides which is considered acceptable. From a quality perspective, the production of red American ginseng is worthy of further investigation by the Australian industry. The establishment of an Australian processing industry for ginseng requires an efficient method of extraction of ginsenosides and their subsequent concentration into a saleable product. Ethanol is a common, acceptable solvent used for the production of a wide range of extracts in the food and pharmaceutical industries. This project found that a relatively wide range of ethanol/water mixtures was able to extract about 85-90% of both neutral and malonyl ginsenosides. The use of 50% ethanol is considered to be the optimal concentration. The project examined spray drying as a representative method of concentrating the alcoholic extract. It was found that using commercially acceptable spray drying temperature regimes, the resulting dried product had a highly acceptable colour and texture with less than a 15%. loss of ginsenosides. It is considered that a market exists for the sale of dried ginseng extract for incorporation into other food or pharmaceutical products. To examine the quality of ginseng products available to consumers, a range of dried and processed ginseng products were purchased from retail outlets and the concentration of neutral ginsenosides determined. Considerable variation was found to exist between products. This variation would arise from different amounts of added ginseng into a product and natural or induced variability between batches of raw material during postharvest operations. Unlike previous similar analysis on other medicinal herbs, there were no products with near zero levels of ginsenosides. However, each of the product classes contained varying concentrations of ginsenosides. The highest concentration was found in root powders and tea bags followed by the dry root and tablets/capsules. The higher values in root powders and tea bags probably reflect the use of hair and smaller lateral root sections which have a higher ginsenosides concentration. The wide range of values found for the tablet and capsules would reflect varying efficiencies of processing as well as variable quality of raw material. The variation within each product class does illustrate the need for growers and processors to exercise quality management of postharvest handling and processing operations in order to standardise on raw material inputs and minimise post-farm gate losses of ginsenosides. From a consumer perspective, the findings highlight the need for improved labelling of products. While many products do contain high levels of ginsenosides they cannot be identified by purchasers. Product labels should contain a more standardised format on ginseng content and include the concentration of nominated active constituents in the final product, similar to processed foods. This information should be supplied both on a unit product weight or volume, as well as on a recommended dose basis. While this project was on quality management issues, interaction with the Australian and international ginseng industry has generated some ideas on how the Australian industry might develop. Since Australia can only be a small contributor to the international ginseng market, it would benefit from having a national ginseng brand and a national marketing and processing operation. This would allow the many small growers to equal access international markets with branded and guaranteed high quality products that could attract a price premium. Such an operation would further assist the economic viability of the industry by allowing the production of commercial products from non-root plant sections such as hair root and leaf. The existence of AGGA offers a ready platform that could
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develop beyond a grower consultative body to become the national marketing and processing organisation.
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1. Introduction The World Health Organisation has claimed that 80% of the world population uses medicinal herbs for beneficial health effects. While medicinal herbs are intrinsically enmeshed in many cultural practices, the use of medicinal herbs over recent decades in Western countries has been growing at an extraordinary rate. This is despite the development of pharmaceuticals achieving substantial advances in alleviating suffering and prolonging life. The interest in medicinal herbs in the West is primarily due to the disillusionment by consumers with medical practices, and indeed with modern technology in general. Increasing use in Asian countries has also occurred due to greater affluence allowing access to previously expensive remedies. Medicinal herbs were traditionally obtained by harvesting plants from natural woodlands and fields. The slow development of a cultivation industry with the continuing reliance on a diminishing source of wild herbs has seen the demand for many herbs greatly exceed supply with resultant substantial price rises. In addition, the market for medicinal herbs in the West is based around processed products resembling those from the pharmaceutical industry which demands a high level of quality control. This has created the need for research to determine the effects of cultivation and processing on the quality of medicinal herbs. Ginseng consists of two major varieties, Panax ginseng (Asian) and Panax quinquefolium (American), with the common name based on their respective native geographical location. American ginseng is a perennial, herbaceous plant of the Araliaceae family, and along with Asian ginseng, traditional use is based on root material. American ginseng has been commercially farmed for the last 100 years in North America and within Asia. Apart from some differences in the processing of roots, both varieties are now used although for different medicinal purposes. Ginseng roots grow in cold climates under heavy shade and is therefore characterised by long growing periods and very low weight returns per annum. Traditional quality characteristics for the Asian ginseng industry can differ throughout Asia, however, common themes involve root shape and colour, with the emphasis on the main and lateral root sections. Processing of ginseng utilizes the main root and discards much of the small lateral and hair roots, and all the aerial sections. Consequently, much research has been completed to determine the optimum farming techniques that will maximise the shape and size of the root.
Hong Kong is the traditional distributor for the international trade in ginseng. The growth in the ginseng industry is seen by the Hong Kong market increasing from 3895 t in 1990 to 5132 t in 1997 (Sadler, 1999). Imports into Hong Kong and Taiwan now have a value of about US $350 million. China produces half of the world ginseng with South Korea contributing 32% and the United States 8%. Ginseng imports to Australia have shown a similar increase from 4 t in 1989 to 17 t in 1994. The price of ginseng root varies according to a range of factors and can command prices of about A$6000/kg for ‘excellent upper bubble root’ to about A$400/kg for ‘#3 red trunk root’ (Sadler, 1999). In Australia, high quality 7-year-old roots have sold for about $1000/kg (Hosemans & Hosemans, 1996). In response to the increased worldwide demand, American ginseng has been successfully cultivated in Australia for the past 10 years. Production of ginseng in Australia is difficult to ascertain but it is estimated that about 150 ha is currently under cultivation with most of the crop destined for export. Australia is agriculturally well positioned to capture a share of the
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international market and cropping is now conducted in a wide range of regions across the southern States. If Australia is to become a successful long-term exporter and to replace imports with locally grown material, it needs to resolve various marketing and quality issues. It is difficult for high cost production countries such as Australia to compete with low cost developing countries on price. However, the Australian wheat industry has shown that it is possible to be internationally competitive on quality. It would seem that the Australian ginseng industry should aim to develop an international reputation as a supplier of high quality raw material as well as processed and manufactured products in order to gain preferential access to the higher price market segment. This will assist in obtaining continuing sales and an adequate economic return from the crop. A major factor in the determination of quality in medicinal herbs is the concentration of those constituents that lead to a health benefit. A considerable number of compounds in ginseng have been identified as being active constituents, however, a group of saponins now known as ginsenosides has been shown in immunological testing to be the most important quality markers. (Li et al., 1996). Until recently, the neutral ginsenosides were the primary group investigated, however, the discovery of the malonyl ginsenosides and development of appropriate quantitative analytical methods has indicated the need to determine the levels of both groups. This is due to the malonyl ginsenosides converting to the neutral ginsenosides as the first step of human metabolism, thereby increasing the effective ginsenosides concentration (Awang, 2000. The research studies described in this report used total ginsenosides as the marker for determining quality. The early growth studies examined only the neutral ginsenosides but later growth studies and all the processing studies also determined the malonyl ginsenosides. 1.2 Objectives The overall aim of the program was to develop quality parameters and associated tests to enable growers to harvest and handle American ginseng to maintain optimum quality, and to identify efficient processing techniques that ensure optimum quality is transferred through to the end products. This was pursued experimentally by determining:
• reliable methods for the analysis of neutral and malonyl ginsenosides, • optimum plant sections and harvest times to maximise levels of ginsenosides, • quality of ginseng roots currently traded from Australian farms, • effect of postharvest handling practices of fresh material on the levels of ginsenosides, • effect of processing operations involved in the manufacture of value-added products
on levels of ginsenosides, and • levels of ginsenosides in retail products available to consumers.
The research program was conducted in close liaison between The University of Newcastle and the Australian Ginseng Growers Association. Apart from educating the researchers in ginseng industry practices, this liaison ensured the individual projects retained industry relevance and assisted in the transfer of findings to industry.
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2. Analysis of ginsenosides
2.1 Neutral ginsenosides Analysis of neutral ginsenosides was achieved by HPLC using the method of Ma et al. (1996). Separation was achieved with a reversed phase column, a mobile phase gradient of water (A) and acetonitrile (B) with 0-20 min being 20-22% B, 20-45 min from 22-46% B at 1.5 ml/min, column temperature of 40°C and peak detection by UV at 203 nm. Figure 1 is a chromatogram of the six neutral ginsenoside standards (Rg1, Re, Rb1, Rc, Rb2 and Rd) which were used to determine the separation characteristics. Figure 2 is a chromatogram showing a separation of ginsenosides in a root extract and the presence of the six neutral ginsenosides is easily discernable and exhibit a good correlation with the separation achieved by Ma et al. (1996). Figure 1 HPLC chromatogram of neutral ginsenosides
(1: Rg1, 2: Re, 3: Rb1, 4: Rc, 5: Rb2, 6: Rd)
0 20 40 60min
0
200
400
1
2 3
4
56
4
0 20 40 60min
0
200
400
mAbs
1
23
4
5
6
7
8
10
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Figure 2 HPLC chromatogram of neutral and malonyl ginsenosides in American ginseng root extract.
(1: Rg1, 2: Re, 3: Rb1, 4: Rc, 5: Rb2, 6: Rd, 7: mRb1, 8: mRc, 9: mRb2, 10: mRd) The method for extraction of ginsenosides from dried ginseng material was to grind the plant part to a powder and actively mix with an organic solvent. A range of particle sizes, methods of mixing, and solvents were extensively evaluated to determine the optimum method for extraction. On the basis of these studies, the method adopted was to grind a dried sample to pass through sieve mesh No.60 (<250 µm), extract with 80% methanol by sonicating for 15 min at room temperature, followed by filtration through filter paper. The extraction was repeated two additional times and the combined extracts were made up to volume. The efficiency of ginsenosides recovery was determined by adding a ginsenoside standard (Rb1) solution into a root sample and extracting, along with a control root sample; >99% of the added ginsenoside was recovered in the analysis. The method was highly reproducible with a coefficient of variation between analyses of about 2%.
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The extraction of ginsenosides from fresh material needed to take into account the presence of a high water content. Following a similar extensive evaluation of the extraction method as for dried material, the method adopted to extract ginsenosides from fresh material was to homogenize a fresh ginseng sample with 100% methanol at high speed for 3 min, sonicate for 15 min followed by filtration. The extraction was repeated two additional times and the combined extracts made up to volume. 2.2 Malonyl ginsenosides The malonyl ginsenosides were determined with an indirect method due to standards not being available. HPLC analysis was performed twice for each sample. The first analysis quantified the six neutral ginsenosides in the extract solution. The extract was then hydrolyzed to convert the malonyl ginsenosides to their respective neutral ginsenosides. A second analysis quantified the neutral ginsenosides in the hydrolyzed extract. Identification of the malonyl-ginsenoside mRb1, mRc, mRb2, mRd was carried out by comparing the chromatogram of hydrolyzed extract with that of the original extract, and also with that reported by Court et al. (1996). The concentration of individual malonyl ginsenosides in the original extract was calculated by subtracting its relevant neutral ginsenoside concentration in the original extract from that in the hydrolyzed solution. The HPLC system adopted was that of Court et al. (1996) which was similar to that used above for the neutral ginsenosides except that a phosphate buffer was the aqueous phase. Figure 2 shows the separation achieved for the four major malonyl ginsenosides, mRb1, mRc, mRb2, and mRd, in a root extract and their elution characteristics in relation to the six neutral ginsenosides. Hydrolysis was performed by removing the methanol in original extract then mixing the residue with 5% potassium hydroxide solution. The hydrolyzed solution was neutralized with potassium hydrogen phosphate and made up to volume with acetonitrile.
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3. Changes in neutral ginsenosides during plant growth
Studies were conducted to determine changes in the neutral ginsenosides between:
• individual roots, • different plant parts over a growing season • roots of different age, and • roots from different growing sites.
3.1 Variation between individual roots The variation in neutral ginsenosides concentration between single roots was analyzed on dry and fresh roots. The data in Table 1 show that the variation in the concentration of neutral ginsenosides between 10 individual 4-year-old ginseng roots that were dried at 40ºC was large with values for total ginsenosides ranging from 32-90 mg/g dried root, with a mean value and standard of deviation of 56±17. There was a similar variation for individual ginsenosides. Fourteen 4-year-old fresh roots were individually analysed. The data in Table 2 show that the variation in ginsenosides concentration between fresh roots was large and similar to the above data with values for total ginsenosides ranging from 34-80 mg/g dried root, with a mean and standard deviation of 54±12. A similar variation existed for individual ginsenosides.
Table 1 Neutral ginsenosides concentration in individual dried roots
Neutral ginsenosides concentration (mg/g dried root) Root Rg1 Re Rb1 Rc Rb2 Rd Total
1 1.1 18.1 27.1 3.13 0.38 1.33 51.23 2 1.5 17.0 32.4 3.33 0.40 1.65 56.32 3 3.0 17.4 23.0 2.87 0.36 2.30 48.93 4 5.9 26.8 25.7 3.8 0.5 2.4 65.0 5 2.7 29.5 49.2 3.8 0.5 4.2 89.9 6 3.1 19.4 20.7 2.9 0.4 1.8 48.4 7 3.2 14.4 11.9 1.8 0.2 1.2 32.8 8 2.4 19.1 26.4 3.7 0.4 2.2 54.2 9 2.9 12.4 21.3 2.9 0.6 1.1 41.3
10 3.2 22.7 42.9 5.4 0.7 3.1 77.9 Mean 2.9 19.7 28.1 3.4 0.4 2.1 56.6
SD ±1.3 ±5.3 ±11.0 ±0.9 ±0.1 ±1.0 ±17.0
Table 2 Neutral ginsenosides concentration in individual fresh roots
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Neutral ginsenosides concentration (mg/g dried root) Root Rg1 Re Rb1 Rc Rb2 Rd Total
1 3.2 23.1 31.0 1.4 0.1 3.4 62.2 2 3.7 16.6 19.7 2.6 0.3 0.7 43.7 3 5.4 23.9 25.2 1.8 0.1 0.8 57.3 4 3.5 22.0 27.0 3.2 0.29 2.2 58.3 5 7.0 12.2 13.1 1.9 0.2 0.4 34.7 6 2.0 19.2 33.3 3.5 0.4 1.2 597 7 4.9 15.4 16.0 2.5 0.56 0.6 40.1 8 2.7 17.0 33.6 1.5 0.2 0.4 55.4 9 3.1 16.2 20.3 2.6 0.2 2.0 44.3
10 1.5 25.5 46.8 3.6 0.3 2.43 80.1 11 19.8 14.1 22.3 3.8 0.4 2.5 629 12 3.9 27.2 23.3 3.2 0.32 1.0 59.0 13 1.9 13.3 23.9 3.2 0. 2.8 45.4 14 1.6 24.4 26.6 3.6 0.4 2.4 59.0
Mean 4.6 19.3 25.9 2.8 0.3 1.6 54.4 SD ±4.7 ±5.0 ±8.5 ±0.8 ±0.1 ±1.0 ±11.7
3.2 Changes in plant parts over a growing season Four-year old ginseng plants were harvested from 2 growers in the Dandenong district, Victoria. The plots were selected at each location before plant germination. Seven harvest times were selected based on the visible plant growth stage. These stages and the harvest dates were:
• Stage 1: sprouted leaf, • Stage 2: distinctive separation of leaf and stem, • Stage 3: plant in full flower, • Stage 4: green fruit set, • Stage 5: red fruit present, • Stage 6: fruit has abscised and leaf senescence has commenced, • Stage 7: aerial parts have totally senesced.
At each harvest, two replicate samples of 5 individual plants were randomly obtained from each grower throughout the plots. Each group of plants was separated into 7 sections comprising main root, lateral root, hair root, leaf, stem, flower and fruit. Each section was analyzed for neutral ginsenosides. 3.2.1 Neutral ginsenosides composition
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Tables 3 and 4 give the proportion of individual ginsenosides present in root and aerial plant sections, respectively. These were obtained over the growing season and averaged over both growers. The data show that Re was the major ginsenoside in both root and aerial sections, while Rb1 was also a major component in the root and Rd in the aerial section. In the root sections, Rb1 and Re were, on average, each present at about 40% of total ginsenosides with Rg1, Rc, Rb2 and Rd each present at <10% although the composition of the hair root differed slightly to that of the main and lateral roots. The aerial sections comprised about 50% Re, 30% Rd and 10% or less of the other ginsenosides. Rd was the only ginsenoside in the root to show a significant change over the season. Figure 3 shows that the composition of Rd followed a quadratic relationship in all root sections over a growing season with the maximum composition occurring when green and mature fruit were present on the plant. In the total aerial plant parts, the proportions of all neutral ginsenosides except Rc changed significantly over the season. Re decreased from about 60% at germination to about 30% at flowering, then increased to about 40% at the aerial senescence stage. However, the proportion of Rd increased from about 10% at germination to about 40% at flowering, then fell to about 25% at the aerial senescence stage. The same changes for both compounds were reflected in leaf and stem. Figure 4 shows the changes in Rd in aerial sections over the growing season. These results are consistent with the findings of Li et al. (1996) who tested leaf and whole root material from American ginseng grown in nine locations across British Columbia, Canada and those of Smith et al. (1996) for main and hair root.
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Table 3 Neutral ginsenosides composition in root sections over a growing season
% of total neutral ginsenosides Plant section
Harvest stage Rg1 Re Rb1 Rc Rb2 Rd
1 7.3 37.4 44.4 5.0 0.7 5.2 2 7.8 38.8 43.0 5.1 0.7 4.7 3 7.7 38.7 42.9 4.5 0.7 5.5
Whole root 4 6.3 35.5 43.6 4.2 0.6 9.8 5 5.5 35.6 44.2 4.5 0.6 9.7 6 7.5 34.1 44.3 5.6 0.7 7.8 7 6.8 36.9 45.2 5.5 0.6 5.0 Mean 7.0 36.7 44.0 4.9 0.6 6.8 LSD (5%) NS NS NS NS NS ±2.8 1 8.1 38.6 45.3 3.5 0.5 4.1 2 8.5 40.4 43.5 3.5 0.5 3.6 3 8.1 41.1 43.6 2.9 0.5 3.9
Main root 4 7.1 37.6 45.0 2.9 0.4 7.0 5 6.3 39.6 45.8 2.2 0.3 5.7 6 9.1 37.7 45.7 3.1 0.4 3.9 7 7.4 43.4 43.5 3.0 0.4 2.3 Mean 7.8 39.8 44.6 3.0 0.4 4.4 LSD (5%) NS NS NS NS NS ±2.4 1 5.0 32.5 44.7 8.0 1.1 8.6 2 5.9 33.2 45.0 7.5 1.0 7.3 3 7.0 32.5 43.2 7.5 0.9 8.9
Lateral root 4 5.1 31.7 43.5 5.3 0.7 13.6 5 4.7 31.4 44.0 6.0 0.7 13.2 6 6.3 30.6 45.0 6.6 0.8 10.7 7 6.6 31.1 49.0 6.4 0.6 6.3 Mean 5.8 31.9 44.9 6.8 0.8 9.8 LSD (5%) NS NS NS ±1.6 ±0.2 ±4.4 1 5.2 37.3 32.6 13.8 1.7 9.3 2 5.1 37.7 33.0 13.5 1.7 9.0 3 6.4 37.1 30.7 12.6 2.2 11.1
Hair root 4 3.9 32.1 31.6 12.1 1.6 18.7 5 3.8 33.1 32.1 12.7 1.5 16.8 6 4.9 32.7 31.3 14.3 1.8 14.9 7 4.6 34.3 33.8 14.5 1.7 11.1 Mean 4.8 34.9 32.2 13.3 1.7 13.0 LSD (5%) NS ±3.8 NS NS NS ±3.8
Harvest stage 1: leaf sprout; Stage 2: separation of leaf and stem; Stage 3: full flower; Stage 4: green fruit; Stage 5: red fruit; Stage 6: some leaf senescence; Stage 7: full aerial senescence
Table 4 Neutral ginsenosides composition in aerial plant sections over a growing season
10
% of total neutral ginsenosides Plant section
Harvest stage Rg1 Re Rb1 Rc Rb2 Rd
1 10.6 63.4 9.5 1.7 4.2 10.6 2 7.9 67.7 6.5 1.5 6.5 9.8 3 3.3 33.0 3.0 4.0 16.1 40.6 Total aerial 4 5.1 36.0 2.7 4.2 15.3 36.8 5 7.8 45.1 2.8 2.8 12.3 29.2 6 11.7 38.6 3.3 2.4 13.8 30.1 Mean 7.7 47.3 4.6 2.8 11.4 26.2 LSD (5%) ±3.1 ±7.2 ±3.1 NS ±5.3 ±8.3 1 10.6 63.4 9.5 1.7 4.2 10.6 2 7.0 67.2 5.6 2.0 7.9 10.3 3 3.1 28.9 2.2 4.1 17.1 44.5 Leaf 4 5.3 32.3 2.1 3.9 15.3 41.2 5 8.7 40.2 2.3 2.8 12.9 33.0 6 11.9 37.0 2.6 2.5 14.5 31.4 Mean 7.8 44.8 4.1 2.8 12.0 28.5 LSD (5%) ±3.4 ±6.8 ±3.0 ±2.2 ±5.8 ±9.5 2 11.4 69.2 9.6 0.0 1.8 7.9 3 7.1 67.1 6.3 0.1 3.8 15.6 Stem 4 5.4 65.7 11.0 0.3 4.0 13.5 5 5.2 68.5 9.6 0.1 3.8 12.9 6 8.3 65.4 13.8 0.0 3.0 9.6 Mean 7.5 67.2 10.1 0.1 3.3 11.9 LSD (5%) ±4.0 NS ±4.6 NS NS ±4.3 Flower 3 2.9 50.6 8.8 6.1 15.5 16.0 4 1.9 54.4 3.3 8.7 21.6 10.0 Fruit 5 2.0 72.6 3.8 4.4 12.0 5.2 Mean 2.0 63.5 3.6 6.6 16.8 7.6 LSD (5%) NS ±5.2 NS ±3.0 ±2.8 ±1.5
11
W h o le ro o t
y = -0 .0 0 0 3 x 2 + 0 .0 7 x + 4 .0 5 (R 2 = 0 .6 0 )
0
1 0
2 0
0 5 0 1 0 0 1 5 0 2 0 0 2 5 0
M ain root
y = -0 .0002x2 + 0 .05x + 3 .29
0
10
20
0 50 100 150 200 250
L ateral root
y = -0 .0004x2 + 0 .10x + 6 .87
0
10
20
0 50 100 150 200 250
Hair root
y = -0.0005x2 + 0.13x + 7.76
0
10
20
0 50 100 150 200 250
Growth time (days)
Figure 3 Change in composition of Rd in root sections over a growing season
% R
d
12
Total aerial
y = -0.002x2 + 0.55x + 7.36
05
1015202530354045
0 50 100 150 200
Leaf
y = -0.003x2 + 0.64x + 6.92
0
10
20
30
40
50
0 50 100 150 200
Stem
y = -0.001x2 + 0.20x + 5.21
0
10
20
30
40
50
0 50 100 150 200
Growth time (days)
Figure 4 Change in composition of Rd in aerial sections over a growing season
% R
d
13
3.3.2 Concentration of neutral ginsenosides The concentration of neutral ginsenosides (Table 5) behaved differently between plant sections over the seasonal growth period. The data show the concentration in the leaf significantly increased while that in the flower/fruit decreased. The main root, lateral root and stem did not show any significant change in concentration while the hair root showed a significant maximum at stage 4 (green fruit) before becoming slightly lower. The combined root sections showed no significant increase, however, the combined aerial sections and the combined plant sections significantly increased over the growing season. The significant increases which occurred in the hair root were due to increases in Re and Rb1 (33% each), and Rd and Re increasing by 15%. The increase in leaf concentration was primarily influenced by Rd (46%), and increases in Rb2 and Re (each about 20%). The significant decreases in the reproductive system of the flower and fruit were due to Re (45%), Rd (19%) and Rb2 (16%). The level of total neutral ginsenosides in the main roots of 30-40 mg/g is well within the range reported for American ginseng roots grown in North America of 20–60 mg/g (Konsler et al. 1990; Li et al. 1996; Court et al. 1996; Smith et al. 1996; Reynolds 1998; Wang et al. 1999). However, the ginsenosides concentration reported by Li et al. (1996) and Konsler et al. (1990) for leaf of 18-42 mg/g is lower than the current findings of about 60 mg/g for mature leaf. This is the first reported data for ginsenosides in flower, fruit, and stem sections of American ginseng. The root hair has been known to contain a higher concentration of ginsenosides (Liberti and Der Marderosian 1978; Smith et al. 1996) which has been proposed due to the higher concentration found in the periderm and cortex root tissues (Tani et al. 1981).
Table 5 Concentration of total neutral ginsenosides in plant sections during growth
Total ginsenosides concentration (mg/g)
Stage Main root
Lateral root
Hair root Leaf Stem Flower/
Fruit Total Aerial
Total Root
Total Root + Aerial
1 32.6 49.2 59.8 23.8 - - 22.9 35.6 35.2 2 34.9 46.1 51.8 38.9 7.9 - 18.2 37.3 35.2 3 30.2 47.9 50.5 50.9* 6.0 43.0 37.6* 34.0 34.0 4 29.0 50.1 80.7* 60.4 5.9 16.0‡ 36.1 35.2 34.9 5 36.6 49.8 63.2 55.5 5.8 6.2‡ 39.0 42.3 42.3* 6 32.4 46.2 76.6 61.1 6.9 - 47.9 39. 4 39.8 7 36.1 52.6 75.6 - - - - 44.7 44.7
LSD 9.3 14.7 25.2 10.9 2.0 5.1 14.4 8.6 7.8 *- Significant increase (p<0.05) ‡ - Significant decrease (p<0.05)
14
3.2.3 Total amount of neutral ginsenosides The accumulation of ginsenosides is a function of the plant section weight and its ginsenosides concentration. The data in Table 6 show a significant increase in the amount of ginsenosides in the main and lateral roots and leaf during the season. While the ginseng industry has focused on using the root sections, Table 6 indicates that the total aerial content constitutes approximately 30% of available ginseng when green fruit were present (stage 4), and this is dominated by the leaf content (85% of total aerial content). Hair root contains between 5-15% of ginsenosides content. Since the concentration of ginsenosides in root sections did not markedly change with time, the total amount of neutral ginsenosides was therefore mainly affected by an increase in dry matter content. The concentration in whole root was significantly higher than in the total aerial part while in root sections, the concentration was hair root > lateral root > main root, and in aerial parts was leaf > flower & fruit > stem. Due to its large weight, the main root contained about 40% of the neutral ginsenosides in whole plant with the lateral root containing 34% and the leaf 19%.
Table 6 Neutral ginsenosides content in each plant section during growth
Total ginsenosides content (mg/plant section)
Stage Main root
Lateral root
Hair root Leaf Stem Flower/
Fruit Total Aerial
Total Root
Total Root + Aerial
1 61.7 12.2 5.6 2.0 2.0 79.5 81.5 2 41.1 10.5 4.4 3.1 2.7 4.0 55.9 59.9 3 80.0* 30.8* 5.7 47.9* 3.9 2.7 54.6* 115.5* 171.3* 4 104.7 53.3* 11.8 60.4 3.7 6.3* 70.3* 169.9* 240.2* 5 88.2 76.8* 10.5 42.8 2.4 4.4‡ 49.6‡ 175.4 225.0 6 82.1 79.3 14.0 46.1 2.7 48.7 175.4 224.2 7 48.9 58.1 8.8‡ 115.7‡ 115.7‡
LSD 38.2 19.7 5.3 32.8 2.8 1.0 24.7 42.9 55.2
*- Significant increase (p<0.05) ‡ - Significant decrease (p<0.05)
3.3 Changes in neutral ginsenosides with root age The increasing age of ginseng roots has traditionally been used as a measure of quality, and the literature shows trends of a linear increase in weight and concentration over 6 years of growth indicating potential benefits of long-term cultivation for greater yield of total ginsenosides. This study was conducted on plants up to 13 years in age obtained from the only farm in Australia with roots of this age range in order to determine the commercial viability of long term cultivation and the results are given in Table 7. Figure 5 shows that a quadratic relationship existed between ginsenosides concentration and root age with a maximum concentration in 8 year old roots. It
15
also shows a linear relationship between root weight and root concentration. This indicates that concentration is primarily a factor of weight rather than root age. This suggestion that ginsenosides concentration is a primarily a function of root weight rather than root age has been a speculation raised in previous publications (Soldati and Tanaka 1986; Court et al. 1996). However, this is the first study to show roots with higher concentrations at a younger age. Previous studies on root age have not extended beyond 6 year old roots, but it is well known that wild crafted ginseng roots increase in size over many years. The older roots sampled in this study were the few remaining plants from limited early experimental plantings in Australia and are probably not representative of a normal well cultivated crop. It is assumed that the smaller root size of the older roots was due to these being the remaining few plants left in the plot with the larger roots having been harvested in earlier years. The results do, however, emphasize the strong relationship between root size and ginsenosides concentration. Table 7 Influence of root age on neutral ginsenosides and root weight.
Root Age Weight (g) Ginsenosides conc. (mg/g)
Ginsenosides content
Ginsenosides production/year
1 0.1 24.9 2.0 2.0 2 0.4 26.4 10.9 5.4 3 1.9 26.5 49.2 16.4 4 2.9 47.8 136.12 34.1 5 4.9 44.4 216.5 43.3 6 4.7 56.5 266.3 44.4 7 3.1 47.2 146.2 20.8 8 4.6 47.5 218.6 27.3 9 4.9 52.3 257.9 28.7
10 5.4 45.1 241.4 24.1 11 5.5 43.9 242.8 22.1 12 2.0 41.0 81.8 6.8 13 3.8 39.8 152.1 11.7
16
R o o t a g e ( y e a r s )
0 2 4 6 8 1 0 1 2 1 4
Con
cent
ratio
n (m
g/g)
1 0
2 0
3 0
4 0
5 0
6 0
y = 9 .2 x - 0 .5 6 x 2 + 1 3
R o o t W eig h t (g )
0 1 2 3 4 5 6
Con
cent
ratio
n (m
g/g)
0
1 0
2 0
3 0
4 0
5 0
6 0
y = 4 .3 3 x + 2 7 .1
Figure 5 Relationship between neutral ginsenosides concentration and root age and root
weight
17
3.4 Variation in ginsenosides in roots grown at different sites The variation of total neutral and malonyl ginsenosides concentration in ginseng root of the same age but grown at different sites was examined on fresh ginseng roots (3 year old) obtained from 10 ginseng growers in Australia and New Zealand. Three replicate samples of 3 individual roots from each ginseng grower were cleaned, dried, ground to <250 µm and analysed for ginsenosides. The analytical data were divided to three groups according to whether the roots were grown under forest with natural tree shade, forest with natural tree and artificial shade or a field with artificial shade. The data in Table 8 show that there was a significant difference in the concentration of ginsenosides due to the growing conditions. The root weight, concentration of neutral, malonyl and total ginsenosides and total amount of ginsenosides of roots grown in a field with artificial shade were higher than in roots grown in a forest with natural or artificial shade. The inter-relationship of root weight with ginsenosides is depicted in Figure 6 and shows a linear correlation between root weight and concentration of ginsenosides. The results suggest that techniques which increase the rate of root growth will also increase the concentration of ginsenosides. Table 8 Root weight and ginsenosides level of roots grown in different conditions
Ginsenosides Concentration (mg/g dried root)
Growing condition
n
Dry weight (g per root) Neutral Malonyl Total
Total amount (mg per root)
Forest 5 0.7 25.8 18.3 44.0 32.8 Forest & artificial shade 2 1.3 26.6 19.3 45.9 57.7 Field & artificial shade 3 6.5 37.2 29.5 66.7 434.8 LSD (5%) ±1.9 ±6.1 ±7.2 ±11.9 ±119.5
y = 3.83x + 41.78
y = 1.71x + 25.19
y = 2.13x + 16.59
0
20
40
60
80
100
0 2 4 6 8 10 12
Figure 6 Correlation of root weight with ginsenosides concentration in roots of the same age grown at different sites
Gin
seno
side
s con
cent
ratio
n (m
g/g)
Total
Neutral
Malonyl
Root weight
18
4. Processing and storage Changes in neutral and malonyl ginsenosides of ginseng root were determined during drying and blanching of fresh root, storage of dried root powder and obtaining and then spray drying of an ethanolic root extract. The levels of neutral ginsenosides only was determined in commercial retail products, as this was an early study. 4.1 Drying temperature The effect of drying temperature on moisture loss and ginsenosides concentration in ginseng root was examined. on 4 year-old roots from a farm in Victoria. The roots were washed then dried at 40º, 55º and 70ºC using a hot air dryer. There were a small number of roots in the dryer so there was no restriction on air movement around the roots. Drying was terminated when the water content in samples was <10% which is a commercially dry root. The time taken to dry roots in the hot air dryer was found to be temperature dependant and the rate of drying at the various temperatures and the time to dry to 90% water loss are shown in Figure 7. The time taken to dry to 90% moisture loss was five times longer at 40ºC than at 70ºC and three times longer at 40ºC than at 55ºC. After drying at 70˚C, the root colour was observed to be darker than for roots dried at lower temperatures but there was no discernible difference between the colour of roots dried at 55º and 40ºC. The data in Figure 7 show that the concentrations of total ginsenosides and malonyl ginsenosides in dried root decreased with an increase in drying temperature but the concentration of neutral ginsenosides increased. This suggests that heat induces some hydrolysis of malonyl ginsenosides to neutral ginsenosides which is also degrading as reflected in the loss of total ginsenosides. The loss of total ginsenosides was about 18% as the drying temperature increased from 40ºC to 70ºC. 4.2 Blanching Steam blanching of fresh Asian ginseng root (white ginseng) has been used for many centuries in China to produce “red ginseng” which is firstly more resistant to degradation during storage but also has different pharmacological properties and hence different medicinal uses (Hideaki, 1999). The effect of steam blanching on the ginsenosides in fresh root was examined with 3-year old roots harvested in Victoria. Blanching was undertaken using a traditional method where roots were placed in a bamboo basket and steamed for 1-4 hr. The steamed samples were dried at 40ºC. Regression analysis (Figure 8) showed that the concentration of neutral ginsenosides initially increased during blanching up to 2 hr but decreased slightly on longer blanching time while the level of malonyl ginsenosides decreased with increasing blanching time and attained near zero levels after 3 hr blanching. The concentration of total ginsenosides linearly decreased with increasing blanching time. No ginsenosides were detected in the blanch water hence the loss was not due to leaching. The roots blanched for 2-4 hr had an appearance similar to red Asian ginseng.
19
There thus appears to be a similar effect of heat during blanching as there was with hot air drying with some conversion of malonyl ginsenosides to neutral ginsenosides but a continual degradation of both forms during heat application. Figure 7 Drying of fresh ginseng root held in a hot air dryer at 40º, 55º and 70ºC.
0102030405060708090
100
0 10 20 30 40 50
Time (hr)
% W
ater
loss
y = 0.04x2 - 4.95x + 173.83
0
10
20
30
40
20 30 40 50 60 70 80
Tim
e to
90%
wat
er lo
ss (h
r)
70º 55º 40ºC
Drying temperature (°C)
20
0
20
40
60
80
100
40 60 80
Drying temperature (ºC)
Gin
seno
side
s co
ncen
trat
ion
(mg/
g)
Total y = -0.42x + 101.74, Neutral y = 0.40x + 30.32, Malonyl y = -0.82x + 71.41
Figure 7a Regression of ginsenosides concentration in root with change in drying temperature
y = -2.3x2 + 11.0x + 24.5
y = -3.3x + 47.4
y = 22.0e-0.84x
0
10
20
30
40
50
0 1 2 3 4Blanching time (hr)
Gin
seno
side
s co
ncen
tratio
n (m
g/g/
dry
wei
ght)
Figure 8 Change in ginsenosides concentration with blanching time of fresh ginseng
roots
total
neutral
malonyl
Total
Neutral
Malonyl
21
4.3 Storage
To investigate the change in ginsenosides in dry roots during storage, dry root powder was placed in a covered petri dish then placed in the dark at 5º, 20º and 35ºC in air at <10% relative humidity and analysed for ginsenosides over a 12 week period. The data in Table 9 show that the concentration of total ginsenosides in root powder held at all temperatures decreased at a faster rate at higher storage temperatures. This was due primarily to a decrease in the concentration of malonyl ginsenosides which occurred in all temperatures but was greatest at the highest temperature. The concentration of neutral ginsenosides showed no significant change when stored at 5° and 20°C with a small increase during storage at 35°C. It appears that at high temperatures there is promotion of malonyl ginsenosides to their corresponding neutral ginsenosides which is largely offset by a similar rate of degradation of neutral ginsenosides. The rate of change in the malonyl ginsenosides at the various temperatures is shown in Figure 9. Table 9 Effect of storage on ginsenosides of dry ginseng root powder at different
temperatures in air of <10% relative humidity
Temperature Amount present (mg/g) Time (wk) 0 3 6 9 12 LSD
Neutral ginsenosides 5°C 45.4 46.0 45.6 46.2 45.0 NS 20°C 46.1 46.1 45.6 46.0 NS 35°C 44.4 47.9 48.1 48.1 ±2.07 Malonyl ginsenosides 5°C 24.4 23.4 23.3 22.1 21.6 ±1.1 20°C 23.3 22.7 22.0 19.9 ±1.9 35°C 23.3 17.3 16.0 14.8 ±2.6 Total ginsenosides 5°C 69.8 69.4 68.9 68.4 66.7 ±0.6 20°C 69.4 68.9 67.5 65.9 ±1.3 35°C 67.7 65.1 64.1 62.9 ±1.1
22
Figure 9 Rate of change in malonyl ginsenosides due to storage temperature
y = -0.0009x2 + 0.016x - 0.28
-1
-0.8
-0.6
-0.4
-0.2
00 5 10 15 20 25 30 35 40
4.4 Alcoholic extract Ethanol and water are recognised as safe and commonly used in the pharmaceutical and food industries to obtain a liquid extract of desired constituents from a range of plant materials. Extraction of ginsenosides from dried ginseng powder was performed by stirring the solvent/ginseng mixture with a magnetic stirrer at room temperature for 30 min followed by filtering through paper. The data in Table 10 show that 50% ethanol in water gave the most efficient extraction of total ginsenosides but there was a relatively high extraction of ginsenosides into solution from solvents containing 30-70% ethanol. The optimum solvent for extraction of neutral ginsenosides was 50-80% ethanol whereas the optimum for extraction of malonyl ginsenosides was 30-70%. The difference between the two types of ginsenosides probably reflects the higher polarity of malonyl ginsenosides resulting in greater solubility in the more polar solvent. Ethanol is not as efficient as methanol in extracting ginsenosides but the latter has toxic properties and therefore not acceptable for food processing. However, the use of 50% ethanol resulted in only a 10-15% reduction in the total extraction of ginsenosides compared with 80% methanol (the most efficient solvent).
Rat
e of
cha
nge
(mg/
wk)
Temperature (ºC)
23
Table 10 Concentration of ginsenosides in root extracts obtained with ethanol/water solvent mixtures
Extraction medium Ginsenosides concentration (mg/g dried root) Neutral Malonyl Total 100% Ethanol 39.0d 11.8e 50.8f 90% Ethanol 48.5b 16.0d 64.5d 80% Ethanol 51.1a 17.2cd 68.3bc 70% Ethanol 50.4a 19.5ab 69.9ab 50% Ethanol 50.4a 20.9a 71.3a 30% Ethanol 47.9b 19.8a 67.7c Water 44.0c 17.8bc 61.8e LSD (5%) ±1.4 ±1.7 ±1.9
4.5 Spray Drying Spray drying is a common method used to dry liquid extracts for use as food ingredients or in tablet formulations. A study was conducted to investigate the optimum spray drying temperatures that converts a liquid extract to a dry ginseng product with maximum retention of ginsenosides. The extract solution obtained above from root powder was spray dried at a small selection of inlet and outlet temperatures based on usage of the equipment for other food extracts. The data in Table 11 show that there was some loss of neutral, malonyl and total ginsenosides during spray drying but the loss was relatively small and was never >15% in any spray dried product. There was a small increase in loss with increase in drying temperature but Figure 10 shows that the spray drying speed increased linearly with increasing inlet temperature, resulting in a shorter time to dry a fixed volume of extract at higher temperatures. On balance, it would be seen that use of the higher temperatures would be more commercially viable for economic operation of a processing unit. The colour of the dried extracts was a highly acceptable cream and had a free-flowing texture.
Table 11 Change in amount of ginsenosides recovered following spray drying at different temperatures
Temperature (˚C) Ginsenosides amount (mg) % Loss of ginsenosides Inlet Outlet Neutral Malonyl Total Neutral Malonyl Total Before spray drying 1423 978 2401 - - - 130 80 1253 913 2143 12 7 11 150 100 1256 833 2089 13 15 13 180 120 1217 833 2050 14 15 15 LSD (5%) ±88 ±67 ±69
24
Figure 10 Effect of inlet temperature on the spray rate of ginseng root extract in 50%
ethanol
y = 0.04x + 1.11
0
2
4
6
8
10
130 140 150 160 170 180
Inlet temperature (ºC)
Spra
y ra
te (m
l/min
)
4.6 Neutral ginsenosides in commercial products Twenty-eight commercial ginseng products which included both American ginseng and Asian ginseng were purchased from herbal stores and health food stores in the Sydney and Gosford regions in February 1999. Descriptions of the 28 ginseng products, analysis of ginsenosides, and calculation of total ginsenoside per package are given in Table 12. It was found that the concentration of neutral ginsenosides in the products ranged from <0.02 to 86.0 mg/g or mg/ml. Among the different types of products, the average ginsenosides concentration was greatest in root powder and tea bag which was > dry root > paste > capsule and tablet > instant tea > liquid products. For the different types of products, there was, however, generally a large range in the concentration of ginsenosides with values of 9-57 mg/g in the dried roots, 34-86 mg/g in powders, 8-70 mg/g in capsules, 54-58 mg/g in tea bags, 3-16 mg/g in instant teas, 14-72 mg/g in pastes, 4 mg/g in the tablet and <0.02~1 mg/ml in liquids. Only five of the 28 products were labelled with the amount of dried ginseng root or ginseng extract or ginsenosides content. The concentration of ginsenosides in three products was lower than specification by about 50% while the other two were similar to the stated content. The distribution and proportion of the major ginsenosides are quite different between American and Asian ginseng (Ma et al. 1996), and can be used as an index in identification and quality control of commercial ginseng products. Most products were found to contain the stated plant species. However, three products, American ginseng dry root from Canada, American ginseng instant tea made by New Life Health Enterprise, Hong Kong, and American ginseng instant tea made by American Ginseng Health Venture, USA showed a chromatogram characteristic of Asian ginseng, although they were labelled as American ginseng. A summary of ginsenosides levels in the different types of ginseng products is shown in Table 13. This shows that the average ginsenosides concentration in American ginseng products was higher
25
than that of Asian ginseng for the same type of product. Since the liquids are intended to be drinks, a more meaningful comparison is to use 100 ml as the base unit against 1g for the dried product. On this basis, the drinks contain up to 100 mg and can be of acceptable quality. The quality relationship between tea bags and instant tea requires an infusion test to determine the relative amounts solubilized in water. Many of the processed products had a similar or high concentration of ginsenosides than dried roots and would therefore be a good quality substitute. Table 13 Summary of ginsenosides level in different types of ginseng product
No. of products Ginsenosides concentration (mg/g or ml)
Type of product
American Asian American Asian Dry root 2 4 47.0 26.6 Powder & tea bag 4 58.2 Instant tea 1 6 16.4 7.3 Capsule & tablet 2 3 38.9 15.1 Paste 2 43.1 Liquid 4 0.54
26
Table 12 Product description, ginsenosides concentration and total amount in 28 commercial ginseng products
Ginsenosides Type Product description Manufacturer Panax Species Weight (g/pack)
Daily dose (g or ml)
Price ($)
(mg/g) (mg/pack)
Dry root
American ginseng (main root) USA quinquefolium 37.5 3-5 30 40.7 1526
American ginseng (lateral root) USA quinquefolium 37.5 3-5 6 53.2 1995 American ginseng Canada ginseng 148 3-5 12 9 1332 Red ginseng (main root) Korea ginseng 37.5 5-10 28 18.5 693 Red ginseng (lateral root) Korea ginseng 37.5 5-10 3 57 2139 White ginseng Japan ginseng 37.5 5-10 20 21.8 818 Powder American ginseng powder Packed by The Quang, Australia quinquefolium 25 * 10 86 2150 Koala Ginseng Gembrook Organic Ginseng, Australia quinquefolium 30 1-2 34.3 1029 Tea bag American Ginseng Tea Nutri Health Food Centre, Australia quinquefolium 36 4 11 58.5 2106 American Ginseng Tea Vincent Trading Company, USA quinquefolium 60 * 15 54 3240 Tea American Ginseng Tea Health Food Enterprise, Hong Kong quinquefolium 60 3 18.5 16.4 984 American Ginseng Tea New Life Health Enterprise, Hong Kong ginseng 60 * 8 9.4 564 American Ginseng Tea American Ginseng health Venture, USA ginseng 60 * 8 10.6 636 Korean red ginseng tea Korean Tobacco & Ginseng ginseng 150 9 25 8.5 1275 Korean ginseng tea Il Hwa, Korea ginseng 150 * 19 7.2 1080 Chinese ginseng tea Wah Yet, USA ginseng 50 * 6 4.6 230 Korean Ginseng Yeoung Je Tea Gae Poong Ginseng Corporation, Korea ginseng 300 * 22 3.7 1110 Capsule Ginseng 1500 Kordel, Australia ginseng 15 1.3 15 7.8 117 American ginseng Vincent Trading, USA quinquefolium 50 1.5 18 70 3500 Korean Red Ginseng Powder Capsule Korea Tobacco & Ginseng, Korea ginseng 15 2.7 15 33.4 501 Jiannao Yangshen Wang Jiang Beijing Tong Ren Tang, China quinquefolium 8.64 0.7-1.4 18 7.8 67.4 Tablet Korean Ginseng Blackmores, Australia ginseng 30 2.2 23.1 4.1 123 Paste Concentrated Ginseng Tea IL HWA, Korea ginseng 30 * 25 72.1 2163 Korean Red Ginseng Extract Korean Tobacco & Ginseng, Korea ginseng 30 3 36 14.1 423 Liquid Panax ginseng Extractum Products & Export Corporation Tianjin, China ginseng 300 10 10.5 1.04 312 Ginseng Royal Jelly Harbin Third Pharmaceutical Manufactory, China ginseng 100 * 3.5 0.03 3 Korean Red Ginseng Drink Korea, importer: Katherina Aussie International, ginseng 130 * 2 <0.02 <2.6 Korean Ginseng-D Hanmi, USA ginseng 120 * 3 <0.02 <2.4
*no recommendation
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5. Farmer survey of growing Practises Survey of ginseng growing in Australia The questionnaire given in Table 14 was mailed in 1998 to 124 ginseng growers who were members of the Australian Ginseng Growers Association. A total of 56 completed responses were received representing a 45% response rate. The survey questions have been categorised into three groups, farm environment, growing practices and grower circumstances and the responses to the questions are given below 5.1 Farm environment Location: More than 90% of the farms currently growing ginseng were located in NSW and Victoria. Age of farm: About 60% of farms first planted ginseng in the period 1996-98. There were only two ginseng farms established before 1994. Elevation: Ginseng farms were located over a wide range of altitudes. There were 20% of farms at <250 m above sea level, 40% at 250-500 m, 35% at 500-1000 m, and 10% at >1000 m. Rainfall: Most farms (70%) received an annual rainfall of 500-1000 mm while 25% of farms received 1000-1500 mm. Temperature: The responses to temperature ranges was variable and it was not possible to collate the information into a coherent format. However, comparison of the farm post code with Bureau of Meterology data show that the mean annual temperature of >90% of farms was in the range of 10-15°C. The most common January temperatures were a maximum of 22-29°C (85% of farms) and a minimum of 1-14°C (80%). The corresponding July temperatures were 10-14°C (90%) and 0-6°C (85%). Aspect: The majority of farms (65%) were situated on sloping ground with 50% having a south to east aspect. Size: The mean farm size was quite small with 60% having an area of <2000 m2, 30% being 2000-4000 m2 with only 10% being >5000 m2. Soil: 85% of growers knew the soil pH which ranged from 5.5 to 7.0, and the soil type while 55% had undertaken a soil test. 5.2 Growing practices Ginseng grown: Virtually all farms (96%) cultivated American ginseng while 54% of farms grew both American and Asian ginseng. Cultivation system: Virtually all farms (98%) were operating on organic growing principles with only one farm managed with conventional modern agriculture.
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Planting: All farms planted ginseng with seed with 40% of farms using both seed and rootlets. About 80% of farms planted ginseng over a number of years. Vegetation environment: A large majority of farms (70%) cultivated ginseng in a eucalypt environment. About 20% of farms were located on pasture land and 10% in a rainforest environment. Shade: About 40% of farms cultivated ginseng under a combination of trees and artificial shade, 35% under artificial shade alone, and 25% under trees alone. For those using artificial shade, the large majority (85%) used material that resulted in 70-100% of shading. Bed design: The large majority of farms (90%) used raised beds with 80% having a bed height of 50-200 mm, and 80% a till depth of 50-200 mm. Irrigation: The majority of farms (75%) irrigated the ginseng beds. The method of irrigation was 35% of farms using hand irrigation, 25% using microspray, 20% an overhead sprinkler, 10% a soaker-hose, and only 5% using drip irrigation. Mulch: A large majority of farms (>90%) mulched the ginseng beds with the most favoured (50% of farms) mulching material being straw with 20% of farms each using leaf litter and seed hulls. About 60% of farms used one mulch material with 40% of farms using 2-3 materials. Fertilisation: Most farms (60%) did not add fertiliser to ginseng beds. However, 70% of farms used a pre-sowing soil amendment with 25% using blood and bone, 15% each using compost, dolomite and manure. About 25% of farms used more than one soil additive. Pests: Most farms (70%) admitted to having a pest problem. The most prevalent pest problem was slugs and snails (55% of farms), with 10% of farms each reporting birds, terrestrial animals and chafers as a problem. Most farms claimed to be able to combat the pest problem. Diseases: About 25% of farms reported having a disease problem with 80% reporting the problem to be of fungal origin. The large majority with a disease problem (90%) had self-diagnosed the source of the problem. Weeds: About half the farms (55%) reported having a weed problem. The major source of the problem was pasture grass (40% of farms), native plants (15% of farms) and dandelion (10% of farms). 5.3 Grower circumstances Time commitment: Only a small proportion of growers (10%) were cropping on a full-time basis although 75% of growers hoped to eventually become full-time ginseng growers. Farm expertise: About 60% of ginseng growers had some background in horticultural cropping. A substantial proportion therefore had no experience in horticultural cropping. Problem issues: Most growers (90%) responded with some problem issue. They covered all aspects of ginseng farming from seed acquisition to international marketing. The most prevalent issues reported were related to seed source (20% of growers) and growing climate (15% of growers) while 10% of growers reported the ability to source information as a problem. Table 14 Survey of cultivation practices of Australian ginseng growers.
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Please tick or fill in boxes. In some questions more than one box may need to be ticked or filled. Leave blank any non applicable questions. Your honesty is appreciated. Please feel free to attach any extra pages of information that you think may be useful in this survey. Question 1 a) What is your farm postcode?………………………………………………………….... b) What is your farm elevation?…………………………………………………………... c) Is your planting on a slope? yes no d) How many acres do you have under current cultivation?……………………………… e) What is the aspect (direction) of your planting?……………………………………….. f) Have you undertaken a soil analysis? yes no g) Do you know what your pH balance is? yes no h) If yes, what is it?…………………………………………………………………….…. i) Do you know your soil type? yes no j) If yes, describe……………………………………………………………………….…. k) Do you know your vegetation type? yes no 1) If yes, describe…………………………………………………………………………. m) Do you know your mean annual rainfall? yes no n) If yes, what is it?……………………………………………………………………….. o) Do you know your mean annual temperature ranges? yes no p) If yes, what are they? Question 2 Which cultivation type are you using? Under trees yes no Under artificial shade yes no Under trees with artificial shade yes no Other (list)………………………………………………………………………………… Question 3 Which species are you growing? Panax quinquefloius (American ginseng) yes no Panax ginseng (Korean ginseng) yes no Eleutherococcus senticosus (Siberian ginseng) yes no Other (list)………………………………………………………………………………… Question 4 What is your growing style? Conventional (chemical sprays & artificial fertilizers) yes no Organic yes no Bio-dynamic yes no Question 5 a) In what year did you undertake your first planting?……………………………………. b) Have you undertaken staggered plantings? (ie. planted new material in successive years) yes no c) Is the material you planted seeds roots
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6. Conclusions and recommendations 6.1 Need for analysis of active constituents If the Australian ginseng industry is to survive in the face of greater international production, particularly from low cost broadacre production in North America, and increasing demands by consumers, it needs to become more quality conscious. The essential quality factor for medicinal herbs is the presence of active constituents, such as the ginsenosides, that confer a health benefit to consumers. Knowledge of the active constituents in harvested and dried roots will allow the development of more efficient quality grading of crops which can lead to targeted marketing of quality-conscious markets, hopefully at a price premium. If the Australian industry chooses to value add to the crop, the analysis of intermediate products during processing will allow correct processing procedures to be established and a consistent high quality product to be marketed. While neutral ginsenosides have been the focus of most recent studies, the relatively recent discovery of the importance of malonyl ginsenosides and their potential hydrolysis to neutral ginsenosides has highlighted a serious deficiency in published knowledge of ginseng medicinal quality. In this study, the importance of malonyl ginsenosides was not recognised until after the growth trials had been completed and hence data for malonyl ginsenosides was only obtained for the processing and storage trials. In any quality assurance system established by the industry, it is deemed essential that both malonyl and neutral ginsenosides are analysed even though this will almost double the cost of analysis. A ratio of 3:2 for the relative proportion of neutral:malonyl ginsenosides was identified in a limited evaluation of fresh roots. If further testing showed this to be a consistent ratio, then it could be possible to use this factor to estimate the level of malonyl ginsenosides where only the neutral ginsenosides were analysed. 6.2 Neutral ginsenosides in Australian-grown ginseng Australian-grown American ginseng roots were found to contain a similar composition and concentration of neutral ginsenosides as roots grown in North America and Asia and should therefore be as acceptable in medicinal quality for the international market as American ginseng grown in other countries. In addition, the level of ginsenosides tended to be at the upper level of the range previously reported for American ginseng. The cultivation of ginseng under a canopy of eucalypt trees has thus appeared not to have a detrimental effect on the accumulation of neutral ginsenosides. The concentration of the total neutral ginsenosides over the seasonal growth period showed little change in the main root and lateral root. The highest concentration of ginsenosides was in the leaf and the hair root and in these plant parts, the concentration significantly increased to a maximum value at the stage when green fruit was present. Consideration of the absolute amount of neutral ginsenosides in plant sections over the growing season, the amount being a function of plant weight and ginsenosides concentration, showed that the main root and lateral root together contained most of the plant ginsenosides due to their high contribution to total plant weight. While the hair root had the highest ginsenosides concentration it contained about 5% of the total ginsenosides due to its relatively low weight. In contrast, the leaves when fully developed contained about 25% of the total ginsenosides from a high concentration and weight contribution.
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Thus, while the ginseng industry has traditionally marketed only the main and larger lateral root sections, utilisation of the leaves and, to a lesser extent, the hair roots could generate a valuable by-product with beneficial medicinal properties. Utilisation of leaves would, however, require harvesting of the plant before the leaves have started to senesce rather than at the current dormant stage. This would appear to be commercially since no reduction in the level of ginsenosides in roots would be encountered if they were harvested at an earlier stage of plant development. In addition, the pharmacological activity of the ginsenosides between the root and leaf would appear to be similar as the main ginsenoside in both leaf and root is Re, which is present in both sections at about 40% of total ginsenosides. The major difference in their neutral ginsenosides was in different proportions of Rb1 and Rd which are both protopanaxadiol ginsenosides. Further evaluation will probably be needed to confirm a similar pharmacology and to ensure a leaf extract does not contain any deleterious substances. In addition, it is unknown if early harvesting of the leaf every year would affect growth of the root. If the leaf could become an annual marketable product, the ginseng plant would then provide an economic return the entire life of the plant. 6.3 Benefit of maximising root size The study on roots of different age showed that root weight and ginsenosides concentration initially increased with increasing root age but the rate of change was not sustained over the 13 years of growth; the maximum ginsenosides concentration occurred in roots that were approximately 8 years old. While there are valid explanations to dismiss the lack of growth in older plants, the overriding relationship was a linear increase in ginsenosides concentration with increasing root weight. This suggests that benefits to be gained by improved plant nutrition would not only be an increase in root size but also an increase in ginsenosides concentration. It would therefore seem to be doubly beneficial for the industry to identify growing practices that can increase the rate of root growth. The association between root size and neutral ginsenosides concentration was reinforced by the survey of ginseng grown by a range of Australian growers which found that for roots of the same age, the concentration of neutral ginsenosides increased with root size. While there was only a limited number of samples in the survey, the results also suggested that field cultivated plants under artificial shade produce a faster growing root and therefore a greater concentration of ginsenosides than forest grown plants. This relationship should be further explored. In this second study, the malonyl ginsenosides were also analysed. 6.4 Need for improved postharvest operations Since the postharvest aspects of managing quality in ginseng does not appear to have been studied in other countries, there is considerable opportunity for Australia to gain a market advantage in retaining ginsenosides through improving such practices. Of particular interest in this project was the interaction of malonyl and neutral ginsenosides and further highlighted the need to study both forms in assessing root quality. Awang (2000) has stated that the malonyl ginsenosides would be converted to the neutral ginsenosides as a first step in human metabolism. This indicates that the total ginsenoside content is be the main criteria for quality. The study on hot air drying showed that the concentration of ginsenosides was affected by the drying temperature. The application of heat caused a loss of malonyl ginsenosides, a small increase in neutral ginsenosides and a loss of total ginsenosides. Hence the drying temperature regime should be minimised to optimise retention of ginsenosides. It is suggested that hot air drying at 55ºC is more advantageous than at 40ºC due to the energy saving caused by the greatly reduced drying time with little loss of ginsenosides. Drying at 70ºC gives a further saving in drying time but with about 20% loss in ginsenosides along with significant root browning.
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The study did not evaluate different technologies of drying such as heat pump, low pressure and freeze drying, but it is suggested that all of these technologies would probably be advantageous in maximising the yield of total ginsenosides as they utilise a lower heat loading in drying products. However, these technologies are also more expensive to purchase and operate. Storage of the dried product was found to be temperature dependent for total ginsenosides with the major change being the conversion of malonyl ginsenosides to the corresponding neutral compounds. The optimum storage conditions for dried material is therefore at low temperature but in packaging that protects the product from absorption of atmospheric moisture and probably also light. The data suggest that dried ginseng can be held for longer than three months without significant loss of active constituents. Steam blanching is a traditional method to produce the "red" ginseng product from Asian ginseng. No published studies are available to show the change in malonyl and neutral ginsenosides during the blanching of ginseng but this study found a similar loss of ginsenosides with increased blanching time as with increasing heat loading during drying. At the optimum blanching time of 2 hr to produce an attractive appearance in the red ginseng product, there was a loss of 15% in total ginsenosides which is considered acceptable. . From a quality perspective, the commercial production of red American ginseng is worthy of further investigation by the Australian industry. The establishment of an industry based on highly processed products requires an efficient method of extraction of ginsenosides and their subsequent concentration into a saleable product. This study has shown that a relatively wide range of ethanol/water mixtures gave a high rate of extraction in the range of 85-90% of both neutral and malonyl ginsenosides with 50% ethanol, a suitable middle of the range solvent. The extraction process can thus operate with relatively high levels of water which improves its economic viability and is operator friendly as the process can tolerate substantial variation in ethanol to water mixtures between batches. The study explored spray drying as one method of concentrating the alcoholic extract and found that a dried product with highly acceptable colour and texture was readily attained under commercially acceptable drying temperatures with a loss of ginsenosides of not more than 15%. 6.5 Quality of retail products The considerable variation found in the concentration of active constituents in manufactured ginseng products arises from different amounts of added ginseng into a product and natural or induced variability between batches of raw material during postharvest operations. Unlike previous studies of this nature with other medicinal herbs (Wills and Stuart, 1998) there were no products with near zero levels other than the liquid beverages where it would be expected due to the relatively large volume consumed compared to a dry product intake. The variation within each product class, however, demonstrates the vulnerability of active constituents to degradation and demonstrates the need for growers and processors to exercise quality management of postharvest handling and processing operations to understand where losses are occurring and to institute systems that minimise loss in quality. Each of the different product classes produced varying average concentrations, which reflect many of the findings found in this study. The highest concentration was found in root powders and tea bags followed by the dry root and tablets/capsules. The dry root result was within the range of material grown throughout Australia, while the root powder and tea bag class probably reflect the use of hair and lateral root sections that are stripped from samples to be sold as whole roots. It is the range of values found for the tablet and capsule (8-70 mg/g for American ginseng and 4-34 mg/g for
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Asian ginseng) which reflects the varying degrees of processing to which ginseng raw material could have been subjected. From a consumer perspective, many products do contain high levels of ginsenosides but they are not able to be identified by purchasers as no product currently provides label information on the level of active constituents or marker compounds. While all products are labelled to show the amount of ginseng added, the method of presentation varies between products and it is difficult for purchasers to make meaningful comparisons between products. An adequate labelling regime would seem to be in the interest of the whole industry to provide recognition for manufacturers of high quality products and eliminate poor quality products. This information should be supplied both on a unit product weight or volume, as well as on a recommended dose basis. Such labelling is entrenched with processed food products. 6.6 Development of the Australian industry While this study was focused on quality management issues, interaction of the researchers with the Australian and international ginseng industry has generated some views on how the Australian industry might develop, particularly in the light of findings of this project. Australia can only be a small player in the international market but to be effectively recognised needs to develop a national approach to branding, marketing and processing. This would provide a platform for the many small growers to access international markets with branded and guaranteed high quality products that can generate a price premium. The economic survival of the industry may depend upon the ability to process commercial products from non-root plant sections such as hair root and leaf. A centralised processing and marketing group would be essential for such product diversity. The researchers have some optimism for the future of a national industry focus based on the inclusive and comprehensive interaction of the members of the Australian Ginseng Growers Association. It would seem to be in the best interests on the Australian industry that the Association develops beyond a grower consultative body into a national marketing organisation.
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7. References Awang DVC (2000) The neglected ginsenosides of North American ginseng (Panax quinquefolium
L.). Journal of Herbs Spices and Medicinal Plants 7, 103-109. Bureau of Meteorology @http://www.bom.gov.au Court WA, Reynolds LB, Hendel JG (1996) Influence of root age on the concentration of
ginsenosides of American ginseng (Panax quinquefolium). Canadian Journal of Plant Science 76, 853-855.
Hideaki M (1999) Study on efficacy of processed ginseng, red ginseng. National Medicine (Tokyo)
53:217-222 Konsler TR, Zito SW, Shelton JE, Staba EJ (1990) Lime and phosphorus effects on American
Ginseng: II. Root and leaf ginsenoside content and their relationship. Journal of the American Society of Horticultural Science 115, 575-580.
Li TSC, Mazza G, Cottrell AC, Gao L (1996) Ginsenosides in roots and leaves of American
ginseng. Journal of Agricultural Food Chemistry 44, 717-720 Liberti LE, and Der Marderosian A, (1978) Evaluation of commercial ginseng products. Journal of
Pharmaceutical Sciences 67, 1487-1489. Ma Y, Luo M, Malley L, Doucat M (1996) Distribution and proportion of major ginsenosides and
quality control of ginseng products. Chinese Journal of Medicinal Chemistry 6, 11-21. Reynolds LB (1998) Effects of drying on chemical and physical characteristics of American ginseng
(Panax quinquefolium L.). Journal of Herbs Spices and Medicinal Plants 6, 9-21. Reynolds LB (1998) Effects of harvest date on some chemical and physical characteristics of
American ginseng (Panax quinquefolium L.). Journal of Herbs Spices and Medicinal Plants 6, 63-69.
Sadler T (1999) Australian Ginseng, RIRDC Publication, No. 99/22. Kingston, ACT Soldati F, Sticher (1980) HPLC Separation and quantitative determination of ginsenosides from
Panax ginseng, Panax quinquefolium and from ginseng drug preparations. Planta Medica 38, 348-357.
Soldati F, Tanaka O (1984) Panax ginseng: Relationship between age of plant and content of
ginsenosides. Planta Medica 50, 351-352. Smith RG, Caswell D, Carriere A, Zielke B (1996) Variation in the ginsenoside content of American
ginseng Panax quinquefolium L. roots. Canadian Journal of Botany 74, 1616-1620. Tani T, Kubo M, Katsuki T, Higashino M, Hayashi T, Arichi S (1981) Histochemistry II.
Ginsenosides in ginseng (Panax ginseng, root) Journal of Natural Products 44, 401-407. Wang X, Proctor JTA, Kakudu Y, KrishnaRaj S, Saxena PK (1999). Ginsenosides in American
ginseng: Comparison of in vitro derived and field-grown plant tissues. Journal of Herbs Spices and Medicinal Plants 6, 1-10.
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Wills RBH, Stuart DL (1988) Levels of active constituents in manufactured Echinacea products.
Food Chemistry in Australia 65(8), 17-19