(i) Production of Vitamins: E. coli bacteria living in human digestive system synthesize Vitamin-B, Vitamin-K2, Thiamin, Riboflavin, Folic Acid, Biotin etc. Currently, several species of bacteria are used to produce vitamins in the fermentation process.
(ii) In dairy industry: Lactobacillus and Streptococcus bacteria are used to make curds, cheese, butter, ghee, whey etc. from milk.
(iii) In leather industry: Hair is removed from leather by tannin process. The rawhide is then twisted and softened using bacterial protease enzymes.
(iv) Processing: Processing of tea, coffee, tobacco etc. requires enzymes secreted by bacteria. This results in the origin of taste and smell. Bacillus megaterium bacteria is used in this case.
(v) Production of organic gas: At present organic gas such as methane, butane is being produced by decomposing dung and garbage with the help of bacteria. Bacteria like Bacillus, E. coli, Clostridium, Methanococcus etc. produce biogas.
(vi) Salt making: Bacteria are used to make tasting salt.
(vii) In chemical industry: Bacteria are used to make chemicals like vinegar (Acetobacter xylinum), lactic acid (Bacillus lacticacidi), acetone (Clostridium acetobutylicum), alcohol, enzymes, vitamins etc.
(viii) Enzyme production: Enzymes are produced from bacteria such as Bacillus subtilis, Clostridium histolyticum, Trichoderma konigi etc.
(ix) Alcohol and acid production: Various acids and alcohols are produced from starch using Clostridium and Bacillus bacteria.