Micro organisms are used to produce many substances and enzymes of industrial importance such ad citric acid, dextrans and cellulose. They are also used to produce substances that are important in medicine such ad antibiotics, steroid hormones and vaccines.
In metal extraction, bacteria are being used increasingly to extract metals such as copper and uranium from low grade ores and waste residue from mines. The low grade or is pilled in a heap and soaked with a leaching solution containing rock dissolving bacteria. The bacteria action releases the metal ions from the rock. These ions dissolve to give a solution from which the pure metal is precipitated. This process provides about 10 percent of the copper minded in united States.
Generally, when micro organisms are used to produce substance, the operating cost is greatly reduced. This is turn lowers the price of the product. For example , the reactions in the manufacture of cortisone , an anti inflammatory agent, was reduced from 37 to 11 with the help of micro organisms. as a result, this important drug can now be produced at much lower costs.
Enzyme technology
Where possible, industries will tend to use micro organisms or their enzymes to bring about chemical conversions. This is because enzymic processes can occur at normal temperatures and pressures, while non enzymic chemical conversions usually need high temperatures and pressures. Chemical plants that operate at high temperatures and pressures are not only extremely costly to construct but they are also potentially dangerous to operate.
Genetic engineering
Using genetic engineering techniques, scientists ate now able to produce micro organisms which acts as 'chemical factories' and manufacture substances difficult to obtain by the usual methods. For example, the hormone insulin is now harvested in large amounts from the culture media of genetically engineered bacteria. This use of micro organisms reduces the cost of many medically useful drugs.
