Microbial Biomass Production Mujtaba Ch

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Mujtaba Chaudhry
Malik Murtaza Khan Kasi
Sanila Shamsi
Mujtaba Chaudhry
• Main Aim is the conversion of substrate into a useful primary or
secondary metabolic product as shown below:
Antibiotics
Organic
Acids
Alcohols
Other
products.
• 1. Production of Target Products :
• as mentioned in last diagram where when once optimal amount
of target product is once achieved the organisms produced are
merely waste materials that have to disposed safely at a cost.
• 2. Dedicated Biomass production:
• The cells produced during the fermentation process are the
products themselves.
1. viable microbial cells are prepared as fermentation starter
cultures and inocula for food and beverages.
2. as a source of protiens.
3. animal fodder.
• Microbial proteins constitute a minor portion in Human diets
• comes from edible microfungi and truffles
• and a small portion from yeast present in bread i.e 2g per
week. Per person.
• Oldest and easy method for yeast production is “Skimming
Method” by S. Cerevisiae.
• Skimming method involved media derived from cereal grains.
• Yeast floated on top and skimmed off, washed and press dried.
• After WW1 shortage of cereal lead to alternative media
usage. In which ammonia, ammonium salts and molasses was
used.
Starter
culture
• Originates from pure freeze-dried sample or agar medium culture.
• Yeast cells transferred to smaller liquid culture flasks then to larger
intermediate flasks and then to large fermenters for 50,000 to 350,000
litres production
• Molasses as carbon and energy source which is pretreated with acid to
remove sulphides and heated to precipitate proteins.
• Molasses is often deficient in amino acids so supplementation with biotin
Constituents
etc. pH 4-4.4
Aeration
• To increase yeild.
• for 30 mins to ripen yeast cells in end when nutrients deplete.
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High glycolytic activity
Rapid utilization of maltose
Osmotolerance
Good storage characteristics.
High growth rates.
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Edible mushrooms and their fruiting bodies.
Good source of proteins
Some are toxic and have narcotic effects.
Involves solid substrate production.
Several advantages in exploitation of such fruiting fungi for
generation of edible biomass.
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90% of total mushroom production value.
Crop produced within 6 weeks.
Decomposers of cellulosic bodies.
naturally found in woodlands and meadows.
A. bitorquis is also grown which is less prone to certain viruses
and bacterial blotch disease of fungi.
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Inoculation preparation
Solid-substrate preparation
Substrate sterilization
Spawn Inoculation
Casing layer of peat
Fruiting body production
• China is the major producer
• Lentinula edodes (Shiitake) one of most favourite and special
mushrooms.
• Others are, Maitake, Enokitake etc.
• Production on modern synthetic logs is much quicker.
Sanila Shamsi
Scp includes whole cell of bacteria, yeast etc
containing carbohydrates , lipids , vitamins and
mineral salts
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rapid growth rate and high productivity;
high protein content, 30–80% on a dry weight basis;
the ability to utilize a wide range of low cost carbon sources.
strain selection and further development are relatively straight
forward,;
• the processes occupy little land area;
• production is independent of seasonal
and climatic variations; and
• consistent product quality.
many filamentous fungi have a capacity to
degrade a wide range of materials and,
like yeasts, can tolerate a low pH, which
reduces the risk of microbial
contamination. They are also more easily
harvested at the end of fermentation than
yeasts or bacteria
Characteristics kept in mind before choosing strain;
• performance (growth rate, productivity and yields)
• on the specific, preferably low-cost, substrates to be
used
• temperature and pH tolerance;
• oxygen requirements, heat generation during
fermentation and foaming characteristics
• growth morphology and genetic stability in the fermentation;
• ease of recovery of SCP and requirements for further
downstream processing.
• structure and composition of the final product, in terms of
protein content, amino acid profile, RNA level,flavour, aroma,
color and texture.
Medium preparation
The main carbon source may require physical or chemical
pretreatment prior to use. Polymeric substrates are often
hydrolyzed before being incorporated with sources of nitrogen,
phosphorus and other essential nutrient.
The fermentation may be aseptic or run as a ‘clean’ operation
depending upon the particular objectives. Continuous
fermentations are generally used, which are operated at close
to the organism’s maximum growth rate (max), to fully exploit
the superior productivity of continuous culture.
Processed in order to reduce the level of nucleic acids.
Involves a thermal shock to inactivate cellular
proteases.
Depending upon the growth medium
used, further purification may be required, such as a
solvent wash, prior to pasteurization, dehydration and
packaging.
Malik Murtaza Khan Kasi
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The Bell process
The Symba process
The Pekilo process
The Bioprotein process
The Pruteen process
• History
reduce the pollution of diary industry
• YIELD
over 80 million per anum
• High Capital cost
High COD
• Efficiency of Whey
45g/L lactose and 10g/L protein
• lactose utilizing Yeast
• Final product , Protible.
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Whey pasteurization
Lactose concentration
Addition of mineral salts
Appropriate conditions
Biomass production
recovery of Yeast.
• Aim and Objectives
• Problem
Not Economically Attractive
high proportion of starch
• Solution
Symbiotic association
Saccharomycopsis fibuligeria
Candida utilis
• Two stage process
1st stage Rate limiting step
S.fibuligeria grown in small reactors
Under sterilized conditions with N and P supply.
2nd stage
Symbiotic reaction
C.Utilis constitutes the final product
• Refining of final product.
• Aim and objective
Production of filamentous fungus
Utilization of spent sulphite liqour
• Process
Addition of suppliments
Inoculation with paecilomyces variotii
• Production
10000 tons of SCP per year from 2 fermenters
Pekilo protein 59% crude protein.
• Production from saturated hydrocarbons
• Mostly used in 1960s and 1970s
• Problems
Immiscible in water
Require purification or protein product treated
Cooling
Aeration
• Methane rich natural gas
• Heterotrophic bacteria
• Continuous fermentation
• Loop fermentor containing NH3, minerals and methane
• Final product pronin 70% protein
• Importance
Fish and animal food and in future may be used in humans food.
• Uses Methanol instead of Methane
• Significance
Miscible in water
Resultant protein do not require purification
High yield
• Problems
Low tolerance by m/o
High heat of fermentation
Oxygen requirement is high.
• Role of ICI in EU
Used methylotrophic bacterium M.methylotrophus for the
production of feed for chicken, pigs called Pruteen
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Worlds largest continuous aerobic bioprocess system
Cycle air lift fermentor with inner loop (3000m3)
Fluid volume of 1.5 *10^6 L
Capable of producing 50000 tonnes pruteen per anum
Costs of fermenter
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