Abstract

                                Ever since Alexander Fleming reported on the bacteriostatic and bactericidal activity of Penicillium notatum in the year 1929, the study of antibiosis and antibiotic substances has advanced to a great extent and more than one hundred antibiotics have so far been isolated from various micro-organisms. Waksman (1947) clarified the confusion regarding the use of the word 'anti- biotic and defined it as, a chemical substance, produced by micro- organisms, which has the capacity to inhibit the growth of and even to destroy bacteria and other micro organisms. Most of the anti- biotics isolated were tested for their use in medical science and a few of them like Penicillin, Streptomycin, Aurcomycin and Terramycin have come into extensive use as chemotherapeutic agents.. The use of antibiotic substances in agriculture, especially against plant diseases, is being worked out in different countries and some encouraging results have been reported.

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