Abstract

                                The earliest knowledge of the antogonistic proper- ties of microbes can be traced to ancient times. Folklores, stories abound among several peoples, to the effect that cheese, mouldy bread and other spoiled food products can be used for controlling human and animal infections. But specific references to antagonistic effect of one microorganism on other could be found in the literature only during the later half of last century. Vuillemin appears to have been the first to use the word 'antibiosis' in the year 1889 to describe the phenomenon of the survival of the fittest among microbes. Marshall Ward in 1899 adopted the word to describe microbial antagonism. Since then people have been using the words 'antibiotic substance' toxic substance', 'lethal principle', 'inhibitory principle', 'staling product', 'bacteriostatic substance', 'antimicrobial sub- stance', etc, to denote the chemical action, now known to be due to antibiotics. The word 'antibiotic' was used as an adjective in the early years to designate processes which are against life. Starting from 1941 Waksman and his collaborators used the word 'antibiotic' to denote the chemical substance. In the year 1945 Waksman cleared the confusion that existed in the definition of the word "antibiotic' by enunciating a clear cut definition. According to him an antibiotic is a chemical substance which is produced by a microorganism and which has the capacity, in dilute solutions, to inhibit the growth of and even to destroy other microorganisms'. Since then this definition has been well accepted by scientists throughout the world and the word antibiotic has firmly established even in the lay minds. In recent time this word has been used to include chemical substances produced by plant and animal tissues, but such expansions of the definition are to be discounted as they will lead again to confusion. The chemicals from plants which possess antagonistic effect on microbes can be called 'plant antibiotics' or 'antibiotic-like sustances as suggested by Waksman.

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