FERMENTATION PRODUCTS

• Antibiotics• Beverages• Enzymes• Foods• Organic acids• Fats• Solvents• Bacterial insecticides• Vitamins & growth factors• Amino acids• Steroids• Miscellaneous

• Antibiotics» Chloramphenicol» Erythromycin» Neomycin» Novobiocin» Penicillin» Streptomycins» Tetracyclines» Vancomycin

• Steroids» Cortisone» Hydrocortisone» Prednisolone

• Enzymes» Amylase» Catalase» Cellulase» Invertase» Lipase» Proteases» Streptokinases

• Beverages» Wine, beer

• Organic acids» Citric acid» Lactic acid» Gluconic acid» Fumaric acid» Itaconic acid

• Solvents» Acetic acid» Acetone» Butanol» Propanol

• Polymers» Dextran» Derivative of hydroxybutyric acid

• Insecticides» spores of B.thuringiensis

• Miscellaneous» Sorbose (intermediate in ascorbic acid manufacture)» Fructose (a liquid sweetner)» Phenylacetyl carbinol (an intermediate in L-ephedrin

synthesis)

Parameters measured/controlled in a bioreactor

• Physical

• Chemical

• Biological

Parameters• Physical

–Temperature–Pressure–Liquid level–Foam level–Agitator speed–Power consumption–Gas flow rate–Medium flow rate–Culture viscosity–Gas hold-up

• Chemical–pH–Dissolved oxygen

–Dissolved CO2

–Exit gas composition–Broth composition (substrate, product,

ion concentrations, etc., )

Parameters

• Biological–Biomass concentration–Enzyme concentration–Biomass composition (such as DNA, RNA, proteins,

ATP/ADP/AMP/NAD/NADH levels)–Viability–Morphology

Parameters

Aerobic & Anaerobic Fermentations

• Obligate Aerobes– Without oxygen, can’t grow/survive

– E.g. Fungi, algae and bacteria such as Acetobacter, Thiobacillus

– Many of microbes used in industry are obligate aerobes

– All moulds belong to this class (e.g. Citric acid production by Aspergillus niger)

Obligate Anaerobes

• Derive their energy for growth from reactions not involving oxygen

• Presence of Oxygen inhibits or is lethal.• Clostridium acetobutylicum is used in the acetone

butanol industrial process• C.pasteurianum is an important nitrogen fixer in nature

Facultative microbes

• Capable of growth either in the presence or absence of Oxygen

• E.g. Yeast, S.cerevisiae, used in the production of ethanol