B) Vitamins
1. Vitamin B12 (cyanocobalamine)
The vitamin is used for treatment of pernicious anemia and as anThe animalimalfeed supplement.
feed
Commercially produced by Bacillus megatheriummegatherium. .
Commercially produced by Bacillus megatheriummegatherium. .
The culture medium consists of nitrogen source, carbon source aThe andndcobalt cobalt. .
The fermentation is carried out in two stages process.
In the first anaerobic phasefirst phase, which lasts between 2 , 2-4 days,cobinamide is produced.
In the second aerobic phasesecond phase, which lasts between 3 , 3-4 days
cobalamine (coenzyme B12) is produced.
Both stages can also be operated continuously in two fermentersfermenters
operated in cascade fashion.
CobalamineCobalamineis almost completely intracellular and is released intois into
solution by heat treatment at 80 80-120oC for 10 10-30 minutes at pH 6.5 6.5-
8.5 8.5. .
B) Vitamins
CobalamineCobalamineis then converted to is cyanocobalaminecyanocobalaminewith KCN.
with The vitamin is then purified by chromatography.
When radioactive Vitamin B12 (used in schilling test for pernicious anemia) is required, radioactive cobalt is usedpernicious used
B) Vitamins
2. Riboflavin (Vit.B2)
Importance
Enhances the energy production.
organism used: - Micro
Ashbya gossypii or Ermathecium ashbyii but both are not suitable for Fermentation medium:
It contains corn steep liquor, peptone and Soya been oil (carbon source).
and bound to the mycelia extracellularly Riboflavin is formed
. mins C for 60 ° Riboflavin is released from the mycelia by heating at 120
Riboflavin is extracted with butanol for pharmaceutical use.
Biosynthesis of penicillin
depends on the condensation of valineand cysteineamino acids to yield 6APA and L-α-aminoadipateas side chain, which is then replaced by various side chains during the fermentation. If the fermentation of penicillin is conducted without the addition of side chain precursors, a mixture of natural penicillinsare produced. Only benzyl penicillin or penicillin G of this mixture is therapeutically effective and all the other produced penicillinsare by-products that create problems during the down-stream processing. However, if phenyl-alanineor phenyl acetic acid are added as a side-chain precursor, so that only the desired penicillin G is produced.
Penicillin was originally produced by a strain of Penicilliumnotatum, which produced pigments and only about 2 international units per milliliter (IU/ml) by surface culture fermentation . The yield of penicillin has been increased about 50,000 times through the use of the non pigmented Penicilliumchrysogenummutants, proper medium, submerged fermentation and proper recovery.
The medium used today contained 10% total glucose (or molasses), 4-5%corn steep liquor, 0.5-0.8% total phenylaceticacid and 0.5% total vegetable oil and the process was carried out by continuous feed.
Recovery of penicillin
The liquid medium containing the penicillin is separated from the fungal cell using rotating vacuum filter.
The fungal biomass is scraped from the surface of the filter drum, dried and used as animal feed supplement.
The filtrate is cooled to 2-30C, the pH is adjusted to 2 to liberate the free acid.
Penicillin is extracted from the filtrate using organic solvent and then extracted back into the aqueous solution after adjusting the pH.
Potassium ions are added and the result in crystalline potassium salt of penicillin G is removed by filtration (or centrifugation) and then dried to yield a penicillin salt with purity over 99%.