The Effects of Electric Shock on the Biosynthesis of Plant Secondary Metabolites

Taryn Wassmer and Jonathan Gillis

Need

http://personalpages.manchester.ac.uk/staff/roy.goodacre/learning/metabprof/levy_nature2004.pdf

Many bacteria are both capable of developing their own resistance to antibiotics as well as spreading this resistance to other bacteria

Secondary Metabolites

http://pubs.acs.org/cgi-bin/sample.cgi/bipret/2008/24/i02/pdf/bp0703329.pdf

Synthesis of pisatin in Pisum sativum, L, var. Little Marvel (Dwarf Pea)

Literature Review

http://www.scielo.br/img/fbpe/bjm/v31n4/a03fig03.gif

Graph D shows the minimal inhibitory concentration of plant extracts and phytochemicals against antibiotic resistant bacteria. Oils and essential extracts from plants continued to be effective against even resistant microorganisms (Nascimento et. al, 00).

Literature Review

http://phytomedics.com/news/papers/poulev_etal2003.pdf

Table 2 shows the effects of elicitation on the antimicrobial activity of plant root extracts. In almost all model organisms antimicrobial activity was either sustained or improved (Poulev, et. al, 03).

Literature Review

http://pubs.acs.org/cgi-bin/sample.cgi/bipret/2008/24/i02/pdf/bp0703329.pdf

Graphs A, B, and C show HPLC profiles from pea hairy roots after treatment with electric current (a), 0.08 mM copper chloride (b), or no treatment (c). Sub-lethal levels of electric current act as elicitors in transgenic and non-transgenic plant tissue (Kaimoyo et. al, 08).

Purpose

• The purpose of this experiment is to view the effects of altered sub-lethal levels of electric shock on the elicitation of secondary metabolites in Pisum sativum, L, var. Little Marvel

Hypothesis

• Null Hypothesis: With respect to elicitation of secondary metabolites, the frequency distribution of values will be similar for all groups

• Alternate Hypothesis: Groups treated with sub-lethal electric current will express significantly higher elicitation of secondary metabolites than the untreated

Pisum sativum, L, var. Little Marvel (Dwarf Pea) n=150

Hydroponics: Experimental and Control:Seeds will be germinated in Rockwool mini-blocks under high humidity for 7 to 9 days, after which the seedlings will be transplanted to a hydroponics tank, through which Hoagland's solution will be continuously circulated

Analysis of secondary metabolites will occur through submersing hairy root tissue in 6 mL of hexanes per gram of tissue for 5 to 24 hours, which would then be allowed to evaporate out and dissolved in 200 µL ethanol to analyze for (+)-pisatin. These would then be analyzed using Ocean Optics UV spectrophotometer (200-400 nm) for presence of (+)-pisatin through the use of Beer’s Law. (Kaimoyo, et. Al. 08)

Data will organized as means +/- standard deviations and run through an ANOVA (p< .05) with a scheffe post hoc test to ensure accuracy.

Experimental Groups: Elicitation of secondary metabolites by electric current in Hoagland’s liquid medium with copper electrodes attached to the S48 Square Pulse Simulator (Kaimoyo, et. Al. 08)

Pulsating electric current

Constant electric current (10mA)

10 Second Square Pulses

5 Second Square Pulses

2 Second Square Pulses