MICROBES IN HUMAN WELFARE
Introduction
• Microbes are microorganisms,
which have a size of lower than0.1 mm.
• Microbes do everyplace in air, soil, water,
outside and outdoors bodies of other organisms, inside thermal reflections or
geysers (with a temperature of 100 °C)etc.
• Microbes can be grown on artificial culture
media where they form colonies, e.g., bacteria, fungi.
• During their metabolism, microbes produce
chemicals, some of which have been in use by human beings since periods.
• A important assiduity grounded on microbes
has been developed in recent time. A careful selection of microbial strains, bettered
system of extraction and purification of the products, have redounded in
enormous yields.
• The use of living organisms in systems or
processes for the manufacture of useful products may involve algae, bacteria,
fungi, yeast, cells of advanced plants & creatures or subsystems of any of
these or insulated factors from living matter.
MICROBES IN HOUSEHOLD PRODUCTS
Microbes have played an important part in the medication
of ménage products.
CURD
• A common illustration is the product of curd
from milk. Micro-organisms similar as Lactobacillus and others generally called
lactic acid bacteria (LAB) grow in milk and convert it to curd. During growth,
the LAB produce acids that coagulate and incompletely digest the
milk proteins.
• A small quantum of curd added to the fresh
milk as inoculum or starter contain
millions of LAB, which at suitable temperatures multiply, therefore converting
milk to curd, which also improves its nutritive quality by adding vitamin B12.
In our stomach too, the LAB play veritably salutary part in checking complaint
causing microbes.
• For product of curds or yoghurt pasteurized
milk is inoculated with a mixture of
Streptococcus thermophilus and Lactobacillus bulgaricus and its lactose is
instigated by keeping it at 40 °C.
• The peculiar or characteristic taste and flavor
of curds is due to presence of lactic acid and acetaldehyde.
• In India, curds aren't generally
commercially produced but in advanced countries large scale manufacture of
yoghurt is done. In U.S.A. alone about 75 lakh kilogram of yoghurt is
manufactured every time.
DOUGH
• The dough, which is used for making foods
similar as dosa, idli, jalebi and bread is also
fermented by bacteria. The puffed-up appearance of dough is due to the
product of CO2 gas. Also the dough, which is used for making chuck, is fermented using baker's yeast (Saccharomyces
cerevisiae).
TODDY
• A number of traditional drinks (e.g.'Todi'
prepared from sap of palms) and foods are also
made by fermentation by the microbes.
• Arrack is attained by distillation of
fermented toddy. However, toddy becomes unpalatable as alcohol is changed to
ginger, If allowed to raise for further than 24 hours.
• Microbes are also used to raise fish,
soyabean and bamboo shoots to make foods.
CHEESE
•Cheese is incompletely degraded concentrate
of milk fat and casein manufactured by the exertion of microbes.
• Different kinds of Cheese are known by their
characteristic texture, flavour, taste and the particularity coming from the
microbes used.
• For illustration, the large holes in ‘Swiss cheese'
are due to product of a large quantum of CO2 by a bacterium named
Propionibacterium shermanii. The 'Roquefort cheese
are grew by growing a
specific fungi on them, which gives them a particular flavour. Roquefort Cheese
employs Penicillium roqueforti for growing.
MICROBES IN INDUSTRIAL PRODUCTS
A variety of microbes are used to synthesize
a number of artificial products precious to human beings.e.g.- potables and
antibiotics.
Artificial product requires the conformation
of large amounts of the product, which typically involves the microbial
responses to do in a specialized vessel called
fermentor or bioreactor.
Downstream processing is the name given to the stage after fermentation when the asked product is recovered and purified.
YEAST
There are principally two
types of yeasts –
Baker's yeast
Alcohol yeast or Brewer's incentive.
• Baker's yeast :- Baker's yeast is generally employed during the medication of food accoutrements to increase the taste of food, flavour in food and nutrients in food. It's grown on molasses. It's also employed as leavening agent. By the deficient declination of complex organic composites (sucrose) by yeast fermentation, alcohol is formed.
• Some
other common products of yeast fermentation are
Beer: It's produced from Hordeum
vulgare (Barley) malt and alcohol content is 4-8%.
Wine: It's produced from grapes, in which
alcohol content is 10-20%.
Brandy: It's produced by distillation of
wine and alcohol content is 43-57%.
Gin: It's produced from European
rye-Secale cereale.
Rum: It's
produced from molasses of sugarcane and alcohol content is 40%.
ANTIBIOTICS
•
The term antibiotic was chased by Selman Waksman (1942).
•
An antibiotic is a substance produced by a micro-organism
which in low attention and inhibits the growth and metabolic exertion of
pathogenic organism without harming the host.
•
Alexander
Flemming was the first to produce an antibiotic ( named penicillin)
from Penicillium notatum.
•
Waksman
and Albert discovered streptomycin and Actinomycin. Burkholder insulated Chloromycetin.
• Antibiotics
are of two types
Broad spectrum antibiotic:
It's an antibiotic which can kill or destroy a number of pathogens that belong
to different groups with different structure and wall composition.
Limited
spectrum ( specific)
antibiotic: It's an antibiotic which is effective only against one
type of pathogens.
·
Action
of Antibiotics: An antibiotic acts on pathogens by
·
Dislocation of wall conflation.
·
Dislocation of plasmalemma form and conflation.
· ( Inhibition of DNA/ RNA/ Protein conflation.
Resistance to antibiotics Pathogens frequently develop resistance to being antibiotics and therefore, newer antibiotics are needed to be produced.
·
The resistance is produced due to
·
development of copious
mucilage..
·
revision of cell membrane antibiotic can not recognize the pathogen.
·
change to L- form by pathogen.
·
mutation in pathogen.
Main
sources of antibiotic product are of three types-
Eubacteriales
– Utmost of this type of antibiotic is attained from Bacillus sp (70%).
Bacillus subtilis produces further than 60 antibiotics and Pseudomonas sp about
30%.
Actinomycetales (Ramified) –
Streptomyces, Micromonospora and Streptosporangium. From single species
Streptomyces griseus further than 40 antibiotics have been attained.
Fungi – Penicillium.
STEROIDS
· They're complex crystallisable lipids having a
tetracyclic hydrocarbon core (one 5- carbon and three 6 carbon rings) and a
long side chain.
·They're ingredients of hormones and some
important biochemicals like cholesterol, progesterone, oestrogen, testosterone,
cortisterone, and cortisone.
ORGANIC ACID
Some organic acids are manufactured by employing fermentation conditioning of fungi and other bacteria. For e.g., Citric acid, ginger, lactic acid etc.
Citric acid
It's attained by the aerobic fermentation of sucrose by
the fungus Aspergillus niger. This acid is used in drug, flavouring excerpts,
food and delicacies; the manufacture of essay, dyeing. It's also produced by yeast.
Acetic acid or Vinegar
Vinegar
product is a two step fermentation process
First step: Alcoholic fermentation
of a carbohydrate into alcohol by incentive.
Second step: Aerobic oxidation of alcohol into
acetic acid by the bacterium Acetobacter
Lactic acid
It's produced by fermentation of corn starch , molasses,
potatoes and whey by Lactobacillus bulgaricus and Streptococcus lactis. It's
the first acid to be produced.
Gluconic acid
It's produced from glucose by fungi like Aspergillus, Penicillium and Mucor.
Fumaric acid
It's produced from sugar by exertion of Rhizopus nigricans (Bread
mould).
Butyric acid
It's attained by Clostridium butylicum.
INTERFERON
Issac and Linderman observed that impunity
due to the conformation of special answerable substances, produced by viral
infected cells. This small group of protein is named-interferons.
Interferon are the proteins released by the
cells in response to a viral infection which they help to combat. These
interferon don't inactivate the contagion, but they make the unattacked cells,
lower susceptible so they're averted from the attack of contagion. They also
help the contagions from taking over the cellular ministry.
Interferon proteins have proved to be
effective in treating influenza and hepatitis, but their part in cancer
treatment is doubtful.
Interferon is produced by Charles Weismann
through the E.coli strain produced by recombinant DNA technology.
There are three major types of interferons
1.
Interferon-α (INF-α, produced by leucocytes or
white blood cells,)
2.
Interferon-β (INF-β, produced by fibroblasts),
and
3.
Interferon-γ (INF-γ, produced by stimulated
4.
T-lymphocyte cells, hence also called
vulnerable interferon.)
INSULIN
It's a proteinaceous hormone having 51 amino
acids arranged in two polypeptides A and B having 21 and 30, amino acids,
independently and joined by S-S disulphide islands.
Sir Edward Sharpy-Shafer (1916) was the
first to note that diabetes of some persons was because of failure of some
pancreatic cells to produce a substance called insulin.
The first genetically engineered insulin attained by recombinant DNA fashion with the
help of E.coli was produced by the American enterprises, Eli-Lilly on July 5,
1983. It has been given the trade name humulin and has been approved for
clinical use.
VACCINES
Product of antibodies against antigens inside
the body is the base of immunity. Process of inoculation of vaccines is called
vaccination. Scientific base of vaccination was established by Louis Pasteur.
First vaccine, discovered by Edward Jenner is for smallpox.
A vaccine contains either weakened or indeed
killed-attenuation pathogens (serum suspense with acridity) which still have
antigens to induce antibody product. All these vaccines are called first generation vaccines. They're
produced by conventional fashion.
Lately new vaccines are produced ( called second generation vaccines). These are
produced by recombinant DNA technology ( inheritable engineering),e.g., Herpes
contagion and Hepatitis-B vaccines. Rearmost vaccines produced synthetically or
synthesized vaccines are called third
generation vaccines.
MICROBES IN SEWAGE TREATMENT
Sewage
is the waste and waste water produced by domestic and marketable sources
and discharged into sewers.
Dangerous
goods of sewage are-
It produces offensive odour.Sewage contains pathogens like contagion, bacteria etc, which results in dispersion of water borne conditions caused by microorganisms.
Due to the addition of sewage and waste,
oxygen situations of water are depleted, which are reflected in terms of BOD (Biological
oxygen demand) values of water.
The industrial and
municipal waste water are treated in sewage treatment plant (STP) prior to disposal in water bodies.
Sewage treatment system involves the following
stages-
·
Primary treatment
·
Secondary treatment.
• Primary
treatment: is a physical process of junking of large and small patches from
sewage through successional filtration and sedimentation. All solids that
settle form the primary sludge and the supernatant forms the effluent.
Primary sludge can be used for preparing
compost or ordure directly or used in the generation of biogas.
•Secondary
treatment: of the liquid effluent from the primary settling tank is a
natural process which involves microbial declination of organic matter.
The primary effluent is passed into large
aeration tanks where it's continuously agitated mechanically and air is pumped
into it. This allows vigorous growth of useful aerobic microbes into flocs (millions
of bacteria associated with fungal fibers to form mesh like structures).
This vastly reduces BOD of the
effluent. The lesser the BOD of waste water, further is its contaminating
eventuality.
Once
the BOD of sewage is reduced the effluent is also passed into a settling tank
where the bacterial flocs are allowed to deposition. This deposition is called
activated sludge which is taken to anaerobic sludge digesters along with the
primary sludge.
Then, anaerobic microbes act
upon organic matter of first produced monomers and also organic acids.
Methanogens also convert the ultimate into a admixture of feasts like methane,
hydrogen sulphide and carbon dioxide.
The effluent from the
secondary treatment factory is generally released into natural water bodies
like gutters and aqueducts.
The ministry of environment
and forests has initiated Ganga action plan and Yamuna action plan to
save these major gutters of our country from pollution.
MICROBES
IN PRODUCTION OF BIOGAS
Biogas is a gassy energy which is attained by
the anaerobic fermentation of beast wastes (like cattle soil, wastes, urine,
faeces etc).
In
pastoral areas of developing countries, it's a common practice to use animal dung for making dung cakes which are used
for energy. Therefore, a implicit toxin of the agrarian fields is wasted in
burning.
The dung
can be put to more use if it's used to induce biogas (gobar gas) and
side by side a stabilised residue to serve as the fertiliser.The energy yield
of biogas is lower than that of dung cakes but the effectiveness of biogas
burners is veritably high. Therefore over all result indicates that product of
biogas is further cost effective.
BIOGAS
PLANT
The
biogas plant consists of a concrete tank (10-15 bases deep) in which bio-wastes
are collected and a slurry of soil is fed. A floating cover is placed over the
slurry, which keeps on rising as the gas is produced in the tank due to the
microbial exertion. The biogas plant has an outlet, which is connected to a
pipe to supply biogas to near houses. The spent slurry is removed through
another outlet and may be used as fertilizer.
Cattle dung is available in large amounts in
pastoral areas where cattle are used for a variety of purposes. So biogas plants
are more in pastoral areas. The biogas, therefore, produced is used for cooking
and lighting.
The technology of biogas production was developed in India substantially due to the sweats of Indian Agricultural Research Institute (IARI) and Khadi and Village Industries Commission (KVlC). Biogas plant works grounded on the process called anaerobic digestion or fermentation of organic matter. Anaerobic fermentation of waste biomass can be visualised in three stages
The
facultative anaerobic microbes degrade the complex polymers to simple monomers
by enzymatic action. The polymers like cellulose, hemicellulose, proteins and
lipids get degraded into monomers but lignins and inorganic mariners are left
as residue because they don't get degraded.
In this
the monomers are converted into organic acids by microbial action under
incompletely aerobic conditions which are eventually converted to acetic acid.
In this
the acetic acid is oxidized into methane by the exertion of anaerobic
methanogenic bacteria. These bacteria are generally plant in the anaerobic
sludge during sewage treatment. These bacteria are also present in the rumen (a
part of stomach) of cattle. A lot of cellulosic material present in the food of
cattle is also present in the rumen. In rumen, these bacteria help in the
breakdown of cellulose and play an important part in the nutrition of cattle.
In this whole process digestion of cellulose takes place at a veritably slow
rate so that it's the “ rate limiting factor in biogas production”.
ADVANTAGE OF BIOGAS
Biogas
can be fluently stored to give a more effective source of energy.
It can
be used for colorful purposes in addition to its use for cooking.
One
derivate of this process is a stabilized residue which serves as a good
fertilizer.
It reduces the overgrowth of faecal pathogens
because of non-availability of exposed waste. Therefore, it's significant in
perfecting sanitation.
MICROBES
AS BIOCONTROL AGENTS AND BIOFERTILIZERS
Biological control is the use of living
organisms to control pests.
Exemplifications of Biological control are-
·
Bioherbicide It
control weeds. First bioherbicide was developed in 1961 and it was a
mycoherbicide deduced from a fungus Phytophthora palmivora which controls the
growth of milkweed vines in citrus vineyards.
· Ladybird
and Dragonflies are useful to get relieve of aphids and
mosquitoes, independently.
·
cochineal insect (Cactoblastis cactorum) to
control of overgrowth of cacti.
· Baculovirus These
are pathogenic contagions, which infect and kill numerous nonentity pests and
other arthropod pests.E.g. Nucleopolyhedro- contagion. Baculoviruses are known
to control pests like potato beetles, aphids and sludge borers.
·
Biofertilizers are
organisms that enrich the nutrient quality of soil.
·
Rhizobium and mycorrhiza serve as
biofertilizers.
·
Rhizobium is a symbiotic bacterium, which
occurs in the root nodes of legumes. It fixes nitrogen (atmospheric) in
presence of leghaemoglobin.
·
Mycorrhiza
refers to the symbiotic association between fungus and roots of advanced plants.
·
Azolla is a
water fern which is an excellent biofertilizer for rice civilization.