The microbiological production of industrial chemicals

The synthetic capabilities of microorganisms are not confined to food, drink and pharmaceuticals. Microorganisms are known also to produce industrial chemicals that can either serve as or be employed to make solvents, lubricants, extractance, adhesives, plastics, surface coatings, explosives, etc. Often an organic substance with industrial applications can be made either biologically or by chemical synthesis, the decision to make it one way or the other being essentially an economic one. A major consideration proves to be the cost of the raw materials. In microbiological fermentation the chief raw material has been found to be the growth substrate, it usually being starch. In chemical synthesis the principal raw material has been found to be petroleum or a derivative of it. The efficiency of the process must be taken into account. Another factor to be taken into account is the cost recovering the product from the fermentation medium. One must also weigh the potential value of by-products, and the cost of disposing wastes.

Microorganisms are known to produce some 200 substances of commercial value, only a few of them being currently made by biological methods in industry, they include ethanol, n-butanol, aceton, acetic acid, amino acids and enzimes. Scientists consider microorganisms to have a larger role in many industries. With the new genetic methods the microbiologists and chemists are able to replace an existing pathway with a new one. To put in another way, they can construct organisms that have new characteristics and capabilities. Thus microbiological fermentation in conjuction with the new techniques could contribute significantly to the production of three broad classes of industrial chemicals: aliphatic organic compounds, amino acids, and enzymes.

Enzymes can catalize both the making and the braking of chemical bonds. Each enzyme is stated to act only on a particular substrate molecule.Commercially produced enzymes are playing an increasing role in medical diagnosis.

The second major class of industrial chemicals is known to be made up of aliphatic organic compounds, which prove to be distinguished by the absence of benzene rings and similar structures. The aliphatic substances with industrial applications can be broadly divided into two categories: solvents and organic acids. The solvents were found to include ethanol, n-butanol, acetone and glycerol; the organic acids have been found by the scientists to include acetic acid, citric acid and lactic acid.

In general the scientists found the solvents not to be made by biological means, although n-butanol, acetone and glycerol were once made that way. Nevertheless, the solvent industry may return to fermentation because of the cost of petrochemicals, the prospect of exploiting thermophilic bacteria and the availability of new feedstocks.

Thermophilic bacteria have been stated to grow rapidly in the range of temperatures between 60 and 75 C. We found their chief advantage over microorganisms to be their faster metabolism.

Microorganisms have been studied thoroughly but still much is to be studied.

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