biotechnology std grade
TRANSCRIPT
Biotechnology
Living factories
What is Biotechnology ?
The use of organisms to make products for man
Raw materialsSuitable organisms
Usually micro-organisms
Biotechnology processes
Foods, enzymes, Antibiotics, fuels
Sewage treatmentWater purification
Where is it used
Brewing
Baking
Dairy Industry
Pollution control
Food Industry
Medicine
Biological detergents
Immobilised enzymes
Ancient Egyptians
Ancient Egyptians Noticed that when grapes were left a silvery dust appeared on them
On leaving them they also noticed they began to break down and leave a liquid behind
Alcohol
Biotechnology been used for thousands of years but was not given the fancy name
What is that dust ?
Yeast !!
It is a single celled fungus
It has no chlorophyll so it has to make its own food
Yeast feeds on the sugar in fruit and makes alcohol
Yeast
It is of great use in two major industries
Brewing
Baking
Baking
After the yeast has been added to the flour mixture the dough is kneaded
The mixture is left and we see the dough rise
The yeast produces CO2 which makes the dough rise
Baking
The dough can now be baked in a hot oven
Brewing
Add yeast to any fruit juice and we will see the yeast convert the sugar into alcohol
water
Fermentation
Glucose alcohol + Carbon Dioxide + Energy
In baking the alcohol evaporates
The above shows Anaerobic Respiration
Little Energy produced in absence of oxygen
Beer making
A very complex and series of controlled measure goes into making beer
There is no involvement of grapes – so how do the yeast get food for energy
The Barley grain
MaltingBefore the yeast can use the grain for food it must be malted
The starch is converted into simple sugars the yeast can break down
The barley is spread out in a large area where it is kept moist and warm and allowed to germinate
Germination sees the starch being broken down into sugar
Malt House
Mash
The germinated grains are killed by heat to prevent the sugar being used in germination
The grains are then crushed into a MASH
Water is added
As the sugar dissolves in the water it is sweet tasting
WORT
Wort Next ?
Extra sugar is added
Hops can be added to give flavour
Wort is boiled to kill bacteria
FermentationThe wort is cooled and yeast is added
The mixture is allowed to ferment until the yeast is killed by the alcohol
Storage
Stored in containers to allow it to mature
It is then filtered then ………
Packaged
Supplied to Consumer
Batch ProcessingRaw materialsNutrients fedInto vessel
Reactor vessel Fermenter
Microbes growing and bringing about fermentation process
Micro-organisms fed in
Product formed
Microbes no longer growing
Products and microbes removed separately
Finally
Yeast are facultative organisms-
will grow with or without oxygen
In the absence of O2, they live by fermentation. End products are alcohol (ethanol) and CO2
In the presence of O2
they live by respiration. CO2 is final product
Torula yeast. Candida utilis
Conditions favoring growth of yeasts: air, sugar, acid food, liquid, wide temperature range
Where yeasts are found: environments high in sugar -skins of fruits, nectar of flowers, surfaces of plants and mucous membranes of animals
Associations with humans:
Some yeasts are normal flora of the oral cavity, skin, GI tract and vagina
Useful fermentations
Saccharomyces cerevisiae is yeast that is used to ferment sugars to ethanol and CO2
CO2 is the desired end product of bread makers that leavens bread.
Ethanol is the sought after end product of brewers and winemakers.
Commercial yeasts for bakers, brewers and wine makers
Harmful associations -Agents of disease in humans and other animals
Candida albicans associates with humans in the mouth,intestine and vagina. It grows in most moist areas. It can cause disease under some conditions.
Candida albicans budding cells and colonies
Harmful associations -Agents of disease in humans and other animals
Candida causes thrush in the oral cavity, athlete’s foot,and is the most frequent cause of vaginitis in women.
Candidiasis in the oral cavity (thrush) and between toes (“athlete’s foot”)
Lactic Acid Bacteria• The main bacteria used in
manufacture of dairy products are commonly known as Lactic Acid Bacteria (LAB).
• The bacteria utilise the lactose in the milk to produce lactic acid.
Cheese Manufacture
Starters are used in the manufacture of cheese.
Main Types• Lactobacillus• Lactococcus• Leuconostoc• Streptococcus
Role of Lactic Acid• The fresh acidic flavour of
unripened cheese• Important to the formation
and texturising of the curd.• Produces volatile flavours • Synthesis of proteolytic and
lipolytic enzymes - important in cheese ripening.
• May influence micro-flora.
Cheese Ripening
• Most cheeses are ripened before consumption from 2 weeks for semi-hard Caerphilly to 2 years for parmesan.
• Ripened by enzymes derived from rennet, starter m/orgs, non-starter m/orgs and from the milk itself.
How do you make cheese?
• Normal produced from anaerobic fermentation from milk
• Involves fermentation of milk (lactose) by lactic acid bacteria (streptococcus)
Milk
(containing lactose)
Starter culture
Rennet added
Soft curd
Firm curd
Salting
Moulding and pressing
Ripening and maturation
The production of cheese
Cheese is produced from Milk ________ using anaerobic bacteria. Anaerobic bacteria respire without using__ Oxygen ______.The way in which cheese is made involves using a starter _ Culture ______ which is added to the milk and left for a
few hours to ferment at a temperature of _ 37degrees ____ C.
The soft curd is then _ Salted ______, moulded and pressed to make
the final cheese.
Yogurt
• A cultured dairy product• Soured by LAB• Role of LAB is to produce acid and
flavour compounds.• Mixed culture usually added to
develop different flavour profiles within the product.
Making yogurt
Milk containing lactose
Lactic acid bacteria added to the milk
Bacteria feed off lactose in milk
Lactic acid produced increases the milk acidity
Milk protein caesin thickens and coagulates to produce yogurt
The production of yogurt• Yoghurt is produced from MILK using
______. These lactic acid bacteria feed on the _______ in the milk and lactic acid is produced which increases the ______ of the milk. As this occurs the milk _______, called caesin, coagulates the milk and thickens producing yogurt!!! Flavouring and colouring can then be added.
BACTERIA ACIDITY LACTOSE THICKENS
SUMMARY….
• The souring of milk is a fermentation process
• Fresh milk contains sugars(lactose)and some bacteria
• The bacteria feed on the sugars• The lactose is converted into Lactic
acid by BACTERIAL FERMENTATION• The increased acidity makes the milk
turn sour
Sub Topic B…Problems with profit and waste…
WORKING WITH MICROBES
Microbes can be harmful…
• Useful microbes like yeast and Lactic acid bacteria are not harmful to humans.
• Some types of microbe are harmful though…
• They cause diseases
Scientists studying these harmful microbes MUST take precautions to STOPthem escaping and contaminating equipment….
..Sterile conditions are VITAL….
• Wear lab.coats,overalls,gloves and masks where necessary.
• Wash hands CAREFULLY.• Sterilise equipment and work
surfaces.• No food or drinks in the lab.• Careful disposal of microbes using
HIGH TEMPERATURES.These precautions are needed in all biotechnologicalProcesses to avoid contamination of pure cultures of otherMicrobes by unwanted types from the surroundings
PENICILLIN WAS DISCOVERED BECAUSE OF POORBIOTECHNOLOGY PRECAUTIONS WHICH LED TO CONTAMINATED CULTURE PLATES IN ALEXANDERFLEMING’S LAB…..BUT OF COURSE,MOST CASES OF CONTAMINATION ARE NOT USEFUL AT ALL…THEY CAN BE VERY HARMFUL….
EG MRSA IN HOSPITALS DUE TO POOR HYGIENEPRACTICE….
DANGER….SPORES !!!
• Precautions during manufacturing processes are very important as well..
• A particular danger can be SPORES from Bacteria and Fungi which are Resistant to normal hygiene measures
THEY CAN ONLY BE KILLED BY VERY HIGH TEMPERATURESIN AN AUTOCLAVE,OR BY CHEMICALS..
USING BACTERIA FOR DECOMPOSITION
• Decay is important as it recycles raw materials and gets rid of waste at the same time.
• Decay is the decomposition of ORGANIC matter by Micro-organisms
• They feed on the waste to provide themselves with ENERGY.
• During the process,both carbon and nitrogen are recycled
DO YOU REMEMBER THE CARBON AND NITROGEN CYCLES ?????
N2
Nitrogen fixing bacteria in soil and nodules of plants
Nitrates are made into proteins in plants
NO3-
Animals get their protein by eating
Death and decay
Bacteria break down the protein into nitrates
NO3-
Which can be taken back up by plants and made into proteins
Denitrifying bacteria use nitrates and release nitrogen into the air
Lightning and the addition of fertilisers also adds nitrates to soil
Nitrogen is returned to the soil so that plants can use it to produce new proteins..
Carbon dioxide reservoir in the air
Animals
Decomposers Plants
eating
respiration
respiration
death
death
respiration
photosynthesis
Carbon is recycled into carbon dioxide which plants needFor PHOTOSYNTHESIS
Kew Gardens compost heap…
…Britains’ largest!
What do we do with our waste then ?????
• Flushed away down the drains and sewers.
• Cannot be emptied into the water system
• Must be treated to be made safe
• Micro-organisms help to make sewage harmless to the environment.
Just flush it away ?
• Untreated sewage causes problems
• It LOWERS the oxygen concentration of rivers
• It also lowers their pH (makes acid rivers!)
• Causes diseases from the poisons,and harmful micro-organisms
Such diseases include Typhoid,Polio,Dysentry and Cholera !!
So what do we do then ?
• Use micro-organisms to breakdown the waste to produce products which are harmless to the environment
• They do this using their ‘decaying’action
• The micro organisms need LOTS of OXYGEN to do this
Why do you think this is ??
Its all to do with respiration..
• Lack of oxygen means ANAEROBIC respiration
• This means that the microrganisms will only partially breakdown waste
• Lots of oxygen allows AEROBIC respiration
AEROBIC respiration allows the COMPLETE breakdown of the waste material
Sewage Treatment-a summary.
National and local legislation regulates the quality of water that can be returned to the environment. A range of purification steps are required to meet the targets:
Consists of three stages:Primary treatment • Bulk physical removal of • suspended organic matter.
Secondary treatment • Microbial degradation to lower the organic content.
Tertiary treatment• Remaining organic pollutants and minerals removed.
Sewage Treatment
Whats in Sewage ??
• A wide variety of waste materials
• Different types of micro organism feed on different types of waste
• So a wide variety of Micro organisms MUST be provided so that ALL the waste can be broken down
THESE ARE SETTLEMENT TANKS WHERE OXYGEN IS ADDEDTO THE SEWAGE BY BIG ROTATING ARMS.WHAT IS THIS OXYGEN FOR ?
USEFUL PRODUCTS FROM WASTE MATERIALS
• BIOGAS (usually methane) can be produced from sewage sludge and domestic refuse.
• High quality PROTEIN foods from waste such as Whey(from cheese making) and fruit pulps (after juice extraction)
In this way,useless or poisonous substances are convertedInto useful substances such as fuel and food…
Biogasutilisation
Biogasutilisation
Electrica
l energy
Electrica
l energyTherm
al energy
Thermal
energy
Feeding in gas grid
Feeding in gas grid
Biogas
cleanin
g
Biogas
cleanin
g
Biogas upgradingBiogas upgrading
Cogeneration
Cogeneration
Cooking
Lighting
Cooling
Heating
Cooking
Lighting
Cooling
Heating
Direct burni
ng
Direct burni
ng
Vehicle fuel
Vehicle fuel
Spreading
Spreading
GardeningGardening
Agriculture Agriculture
Transport
Transport
Energy crops, grass from Landscape
maintenance (grass, maize, beets)
Agricultural residues (manure, slurry)
fermentation
fermentation
Bioenergy System with Liquid and Solid Feeding
StorageStorage
Separation
Separation
solid components become compost
solid components become compost
liquid components back to the fermentation or spreading
liquid components back to the fermentation or spreading
Profit from waste !!!
• The main aim in UPGRADING waste is to convert it to more useful substances
• Most commonly this involves raising the levels of PROTEIN,or increasing the ENERGY CONTENT of the waste
Just one more thing on fermentation…
• Some plant material can be used to produce ETHANOL by fermentation.
• Ethanol and Biogas have advantages over the use of fossil fuels such as oil and coal
• The raw materials are renewable and will not run out
Burning them produces less pollution than the fossil fuels
REPROGRAMMING MICROBES.
First of all….some Bacterial Genetics
• Bacteria have a chromosome which controls all of its activities
• Genetic engineering allows us to transfer pieces of chromosome from different organisms into bacteria
• This allows bacteria to make new substances
• This process involves several steps…..
How is it done ?
• Useful genes in other organisms are identified
• The required gene is separated from the chromosome
• The gene is inserted into the ‘host’ bacteria
• The bacteria reproduces containing the new gene
• Increased production of useful products results from this
THIS IS CALLED GENETIC ENGINEERING…
Genetic engineering vs. selective breeding
selective genetic• Single
characteristics not always possible
• Very slow..depends on animals/plants with relatively long life cycles
• Desired characteristic confined to one type of organism
• Single characteristic can be selected
• Very rapid..bacteria reproduce very quickly
• Characteristic can be transferred form one organism to another
More advantages of genetic engineering..
• Expensive and difficult to produce substances can be made cheaply and easily eg……..
• Insulin for Diabetes• Antibiotics such as
Penicillin• Vaccines for the
control of diseases
This is how its done………
Genetic EngineeringGenetic Engineering
First, the nucleus of human cells are burst
Human cellNucleus
Genetic EngineeringGenetic Engineering
The chromosomes are cut up into small fragments and the required gene identified.
Chromosome fragments
Fragment containing required gene
Genetic EngineeringGenetic Engineering
Next the fragments are spread out and the required one isolated.
Segment with required gene
Genetic EngineeringGenetic Engineering
Cytoplasm
Bacterial chromosomeBacterial cell wall
Plasmid
Structure of a typical bacterium
Genetic EngineeringGenetic Engineering
Plasmid
Plasmids are loops of DNA separate from the main chromosome.
Genetic EngineeringGenetic Engineering
By using special enzymes, we can make a cut in the plasmid DNA
Cut here
Next, we introduce the prepared HUMAN gene to the mixture. If all goes according to plan, the human gene will fit into the cut in the plasmid
Prepared human gene
Genetic EngineeringGenetic Engineering
PLASMIDS ARE INSERTED INTO THE BACTERIA
Genetic EngineeringGenetic Engineering
Agar containingnutrients
Colonies growing from single bacteria containing the plasmids with the human gene
Genetic EngineeringGenetic Engineering
These colonies will have the correct plasmid to produce the product from thehuman gene. Cells from this colony will be grown on a large scale and the mediumanalysed for the presence of the product from the human gene, eg Insulin
The need for Insulin is increasing…
• People are living longer• Populations are increasing• Diabetes often occurs at middle/old
age• Unhealthy lifestyles contribute to
diabetes• Better medical treatments mean that
people are living longer
So what's the problem then ?
• Purifying Insulin from the pancreas of slaughtered cattle and pigs is slow and expensive.
• Animal Insulin is not as effective as Human insulin.
• Some people are allergic to animal Insulin
• Many diabetics object to the use of a product from slaughtered animals…
And the solution ?• The insulin produced from bacteria
which have been genetically altered is pure Human insulin
• Its production is quick and inexpensive• It has non of the physiological and
ethical problems associated with the use of cattle or pig insulin
BUT….There are dangers involved with genetic engineering.It involvesCreating new strains of bacteria which MIGHT prove harmfulTo animals and plants……an ethical dilemma..
Biological detergents…
• Contain enzymes produced by bacteria
• Many of the stains on clothes are Proteins(blood,gravy,grass,etc)
• The enzymes break down and digest proteins
• They work at relatively low temperatures
• This saves energy and money
Disadvantages of Batch Processing
• Slow and Expensive….Fermenter has to be cleaned and sterilised between each product batch.
• Enzymes or micro-organisms cannot be recovered for use again at the end of each batch every time.
• Continuous flow processing solves these problems by relying on..
ENZYME IMMOBILISATION TECHNIQUES
Immobilised Enzymes..
• Restricts the movement of Enzymes or cells
• Usually by attaching them to beads of jelly or other carriers
• Keeps the enzymes/cells separate from the product
This results in increased productivity and reduced costscompared to batch processing
Antibiotics
• Chemicals which prevent the growth of micro-organisms.
• There are many different diseases caused by bacteria.
• Different bacteria are affected by different antibiotics
• One antibiotic may only work against certain types of bacteria
A range of different antibiotics is needed for the treatmentOf bacterial diseases
Production of antibiotics, most notably penicillin and the beta lactam antibiotics are produced by Penicillium molds
The penicillin is secreted by the mould and collected from the Nutrient jelly..