Fermentation process of Vitamin B₁₂

Contents

• Production of Vitamin B₁₂

Session Objectives

At the end of the session, student will be able to

• Explain the fermentation process of Vitamin B₁₂

• Describe the source of Vitamin B₁₂

• Discuss the deficiency symptoms and uses of Vitamin B₁₂

Vitamin B 12

• Water soluble vitamin

• Cobalamin

• Normal functioning of brain and nervous system and formation of RBC

• Rickes et al – 1948 – recovered a small amount of a component - liver extract – crystallized – Vit B₁₂ – COBALT COMPLEX

• Pernicious anemia

• Stokstad et al – 1948 – culture of bacteria – Flavobacterium solare

• No fungi, plants, nor animals (including humans) are capable of producing vitamin B₁₂.

• Only bacteria and archaea have the enzymes needed for its synthesis.

• Sources of B₁₂ are animal products (meat, fish, and dairy products) and supplements.

Deficiency

• Severe damage to brain and nervous system

• Fatigue, depression, poor memory

• Mania and psychosis

• Anaemia, mouth ulcer, tingling feet

Structure of Cobalamin

• Organometallic compound

• Corrin ring

• 4 Pyrrole subunits

Production – Fermentation

Choice of organisms

• Obtained – by product of Streptomyces antibiotic fermentation

                     –by product of acetone-butanol fermentation

• Most of the vit B12 in the sludge solids is synthesized by microroganism during the activated sludge treatment of sewage

• Addition of cobalt salt only slightly increases the yield

• Commercially produced by direct fermentation with Streptomyces olivaceus

Medium

• Glucose

• Cobalt chloride (CoCl2.6H2O) – 2 to 10 ppm – precursor

• Duration – 3-4 days or until lysis of mycelium occurs

• 25 ˚C

Recovery

• Vit B₁₂ remains in microbial cells until autolysis sets in – recovery is done before autolysis sets

• Solids and mycelium – filtered or centrifuged – separated from broath – dried

• Used – vit B₁₂ enriched animal feed supplement

Alternate method of recovery

Completed fermentation broth

                                                                             â Acidification and sodium sulfite added Centrifuge or filter

Residual solids and spent mycelium separated

â

Fluid - evaporated under vacuum

â

Vit B₁₂ – small amount

â

Purified and crystallized

Other organisms used

• B. megaterium

• Recent – aerated submerged bacterial fermentation – strains of

              – Propionibacterium (Beet molasses medium & Cobalt precursor)

              – Pseudomonas (Beet molasses medium & Cobalt precursor)

Summary

• Vit B₁₂ - Obtained – by product of Streptomyces antibiotic fermentation

• By product of acetone - butanol fermentation