Applied
Microbiology :-
The
branch of biology which deals with the study of enzymes related to some
prokaryotes and eukaryotic microbes, proteins, applied genetics, molecular
biology etc. is called as applied microbiology.
Industrial Microbiology :-
When microbiology is used for commercial purpose as well as
economic, social and environment related processes, then it is called as
industrial microbiology.
Main features of
industrial microbiology
1) Using
fermentation process, different products such as bread, cheese, wine and raw
material for chemical reactions is produced.
2) Use of microbes
for garbage management and pollution control.
Products
A. Dairy products
By preparing various milk
products, one can preserve milk for a long time. Cheese, butter, kefir, yoghurt
etc. are some important milk products.
While
making these products the water content and acidity of the milk is changed. Due
to this, texture, taste, aroma and flavor is changed.
Basic process on milk in dairy
1) Milk is
pasteurized at the start to destroy harmful microbes.
2) Then the
milk is fermented by using lactobacilli.
3) In this
process, lactose sugar present in the milk is converted into lactic acid.
4) Due to
lactic acid, the milk proteins get coagulated.
5) Besides
this, compounds with taste and flavor are formed like Diacetyl.
Production of Yoghurt
1) Yoghurt
is produced from the milk with the help of lactobacilli.
2) The
condensed milk powder is mixed with milk to increase the protein content of the
milk.
3) The milk
is boiled and then it is cooled till it becomes lukewarm.
4) Then the
bacterial strain of Streptococcus thermophilus and Lactobacillus
delbrueckii
are added to it in the proper proportion.
5) The
streptococcus bacterium converts the milk into solution containing lactic acid.
This makes the protein to get out. It makes the yoghurt dense.
6) The
lactobacilli form aldehydes like compound which gives the characteristic taste
to the yoghurt.
7) Various
fruit juices can be mixed with yoghurt to impart different flavours forming
strawberry, banana, mango etc.
8) The
pasteurization is carried out to increase the self life of yoghurt and improve
its probiotic properties.
Butter:
Butter is
of two types namely sweet cream and cultured. For large scale production of
cultured butter microbes are used.
Cheese
production:-
1) Cheese is
made from cow’s milk. Chemical and
microbiological testing of milk is done.
2) Three
types of bacteria i.e. Lactobacillus
lactis, Lactobacillus cremoris and Streptococcus thermophilus along
with some color is added to the milk.
3) It
imparts sourness to the milk and it is converted into yoghurt like substance.
4) The water
from this yoghurt is removed to make the yoghurt denser.
5) The enzyme
protease is added to the mixture to make it denser.
6) Later,
cutting the solid yoghurt into pieces , washing, rubbing, salting and mixing of
essential microbes, pigments and flavours is done.
7) The
pressed cheese is then cut into pieces and sorted for ripening.
Probiotics:-
1) Probiotic substances are
mostly milk products containing live active bacteria.
2) The useful colonies of
bacteria are produced in the elementary canal of human being due to the
probiotics.
3) Probiotics decreases the
population of harmful microbes like clostridium from our intestine.
4) It enhances the immunity
due to regular intake in the diet.
5) Probiotics reduces the ill
effects of harmful substances formed during metabolic activities.
6) Due to intake of antibiotics
useful microbes becomes inactive, but probiotics makes them active again.
7) Now a days probiotics are
used for treatment of diarrhea and treatment of poultry.
Bread:-
1) Breads
are produced from the flour of cereals.
2) Dough is
prepared by mixing together the baker’s yeast (Saccharomyces cerevisiae) ,
water, salt and other necessary materials with flour.
3) Due to
fermentation, sugar is converted into the carbon dioxide and ethanol.
4) While
baking the dough carbon dioxide is released and the bread becomes fluffy and
spongy.
5) Compressed
yeast containing carbohydrates, proteins, vitamins and minerals is used in
commercial bakery industry.
6) Dry
granular yeast is used for domestic use.
Vinegar production
1) 4 %
acetic acid is called as vinegar.
2) With the
help of the S. cerevisae, ethanol is obtained by fermentation of
fruit juices, maple syrup, sugar molasses, starch of the roots etc.
3) Then for
the microbial degradation of ethanol, a mixture of bacterial strains like Acetobacter
and Glucanobacter is used. Ethanol is converted into acetic acid and other
by-products are obtained.
4) The
acetic acid is separated from mixture by rarefaction.
5) Potassium
ferrocyanide is used to bleach this acetic acid.
6) Finally
the pasteurization is done followed by the mixing of small amount of SO2 (Sulphur
dioxide) gas to produce vinegar.
Uses of vinegar
1) Vinegar
is used for the preservation of pickles, sauces, ketchups, chutneys etc.
2) It
imparts the sour taste to food materials.
Soya
sauce:-
Fungus Aspergillus oryzae is used to ferment the mixture of flour of wheat or rice and soyabean to produce soya sauce.
Microbial
enzymes:-
The enzymes obtained by the activity of microbes are used in the industrial processes. These microbial enzymes are better than chemical catalysts.
Advantages
of microbial enzymes
1) Microbial enzymes work at the low temperature, pressure and Ph
2) Energy is
saved in the processes using microbial enzymes.
3) There is
no need of erosion proof instruments for the processes.
4) Unnecessary
products are not formed in the process.
5) Purification
is not needed and hence expenses on purification are reduced.
6) Enzymes
can be reused.
7) Microbial
enzymes are eco-friendly because elimination and decomposition of waste
material is avoided.
Use of microbial enzymes in industries:
1) Microbial
enzymes are used in detergents in cleaning process to remove dirt at low
temperature.
2) It is
used to obtain glucose and fructose syrup from corn flour using enzymes of
cacilli and streptomyces.
3) They are
used in various industries like cheese, paper, textile, leather, plant extracts
etc.
Xanthan Gum:-
1) Xanthan
gum is obtained by fermentation of starch and molasses with help of Xanthomonas
species.
2) It is
soluble in hot water and cold water so it is very useful.
3) It is
used in the production of pigments, fertilizers, toothpaste, weedicides, high
quality paper etc.
4) It is
used to impart thickness to ice-cream, milkshakes, chocolates, instant soups
etc.
Antibiotics:
Antibiotics are the
medicines obtained from the bacteria and fungi by carrying out certain processes.
Some human diseases and
other animal diseases are controlled by using antibiotics.
Examples: Penicillin,
cephalosporin, gentamycin, streptomycin, Tetracyclin, ampicillin, amoxicillin,
monobacton, bacitracin etc.
Microbes
and fuels:-
1) Methane
is obtained from agricultural and industrial waste by microbial anaerobic
decomposition.
2) Ethanol
is a clean fuel which is obtained during fermentation of molasses by yeast.
3) Hydrogen is
a fuel of future. It is released when bacteria perform bio-photolysis of water.
Advantages of fuels obtained from microbes
1) They are
not polluting.
2) The
conventional fuels are exhaustible. After few hundred years, they will be
exhausted. Fossil fuels cause lot of air pollution due to emission of carbon
dioxide. So it is necessary to increase the use of such fuels.
Microbial pollution
control:-
1) With the help of suitable
microbes, the environmental problems can be tackled.
2) Microbes are used in biogas plants, compost
production, sewage treatment etc.
Bio- fuel:
Bio- fuel is a good and renewable
source of energy. They are easily available and in abundance. They are called
as reliable fuels of the future. They are available in the following three
forms.
1) Solid:-
Coal, dung, crop residue, dung cakes etc.
2) Liquid :-
Vegatable oils, alcohol, bio-diesel etc.
3) Gaseous
:- Gobar gas, coal gas
Land
filling sites:-
1) In the land- filling sites the degradable wastes are transferred. Such sites are
away from the residential area.
2) Large pits are dug in open
spaces. These pits are lined with plastic sheets. So the leaching of toxic and
harmful materials are avoided to reduce soil pollution.
3) Compressed waste is put in
the pit and is covered with the layers of soil, sawdust, leafy waste etc.
4) Specific biochemical
substances are added for speedy decomposition.
5) Bioreactors which are the
mixtures of bacteria are mixed at some places.
6) Soil microbes and other
top layers decompose the waste.
7) Soil slurry is used to
seal the pits completely.
8) After a certain period, best quality compost is formed. Such sites can decompose more and more biodegradable waste and can be used again and again.
Clean Technology :-
Microbes have
natural ability of decomposing the manmade chemicals. Hydrocarbons and other
chemicals are transformed with the help of these abilities.
Cleaning the oil spills of rivers
and oceans with help of microbes
1) The oil
spills take place in rivers or oceans due to several reasons.
2) This
crude oil is highly toxic to the flora and fauna of the river or ocean.
3) Oil
spills can be removed by using mechanical means but it is very difficult.
4) The
culture of microbes like Pseudomonas species and Alcanovorax borkumensis.
5) They have
the ability to destroy the pyridines and other chemicals present in the HC.
6) They are released
at the place of the oil spills to clear them.
7) These
bacteria are called as hydrocabonoclastic bacteria (HCB). They decompose the HC
and bring about the reaction of carbon with oxygen.
8) In this process CO2 & water is formed. In
this way oil spills are cleaned.
Conversion of soil polluted by acid rain
into fertile land
1) Acidophillium
spp. And Acidobacillus ferroxidens arethe bacteria which have the
capacity to use sulphuric acid as their energy source.
2) Since
this sulphuric acid is present in the acid rain, the bacterium becomes the
right choice to control the same.
3) In this
way, bacteria can control the soil pollution occurring due to acid rain, making
the soil fertile again.
Decomposition of plastic bottles by using microbes
1) Plastic
bottles are formed from the chemical substances PET ( Polyethylene
Terephthalate Polyster).
2) It has
been observed that species like Vibrio, Ideonella sakaiensis can decompose PET.
3) Species
of fungi like actinomycetes, streptomyces, nocardia, actinoplanes have the
ability of decomposing rubber from garbage.
Microbes and farming
Microbial Inoculants:
1) Microbes
containing inoculants are produced by the process of fermentation.
2) They are
used for spraying on seeds before sowing.
3) Some of
them are released into the plants.
Examples:
Solution containing Azotobacter, artificial nitrogenase.
Benefits
of Microbial Inoculants:
1) Microbial
inoculants provides the nutrients to the growing plants.
2) They
increase the fertility of the soil.
3) They
improve the quality of vegetarian food.
4) Harmful
chemicals present in the soil are removed by using microbial inoculants.
Bioinsecticides:
1) Through
biotechnology, bacterial and fungal toxins are directly integrated into plants.
These plants are protected against fungal and pest attack.
2) Being
toxic to insects, they do not consume these plants.
Example:
Spinosad
Give
reasons:
1) Use of mutant strains has
been increased in industrial microbiology.
1)
In
industrial microbiology, the commercial use of microbes is done.
2)
In
such experiments, various economic, social and environmental issues are
handled.
3)
To
find the more effective solutions and the products the mutant strains are used.
2) Enzymes obtained by the
microbial process are mixed with the detergents.
1) When detergents are mixed
with the microbial enzymes, they works efficiently.
2) These enzymes works at low
temperature.
3) For better results,
enzymes are mixed with detergents.
3) Microbial enzymes are used
instead of chemical catalysts in chemical industries.
1)
Microbial
enzymes are active at low temperature, pressure and pH
2)
The
energy is saved.
3)
The
expenses on purification of the product are minimized.
4)
Unnecessary
byproducts are not formed.
5)
Microbial
enzymes are ecofriendly.
Answer the following questions
1) How the bread does become
spongy?
For the preparation of bread baker’s yeast is used
in the dough. It is anaerobic organism. Anaerobic fermentation results in the
formation of carbon dioxide and ethanol. When the dough is baked, the carbon
dioxide gas escapes and bread becomes spongy.
2) What are the benefits of
mixing ethanol with petrol and diesel?
1) Petrol and diesel are
non-renewable sources of energy.
2) When only petrol and
diesel is used as fuel there is increase in pollution.
3) When petrol and diesel is
mixed ethanol, the proportion of pollutants which are emitted in the atmosphere
becomes less.
4) Due to the addition of
ethanol, the price of fuel becomes less.
3) Which plants are
cultivated as fuel?
1) Ethanol is obtained from
the wheat, maize, beet, sugarcane and molasses of sugarcane.
2) Biodiesel is obtained from
the plants like jatropa, mahua, palm, jute, sunflower, mustard and some types
of algae.
