STUDIES ON THE INHIBITORY ACTION OF PLANT COMPONENTS ON THE GROWTH OF BACTERIA. 4. EXPERIMENTS ON THE INHIBITORY ACTION ON BACTERIAL GROWTH, OF GREEN TEA LEAVES AND COMMON GINGER ROOT

Abstract

For the purpose to find out the action of plant components on the growth of bacteria, crude juices of 20 kinds of fresh plants were prepared by soaking them separately in hot water for a certain period of time, and the plant juices so obtained were added to the protein-free synthetic medium and test bacteria were cultured in order to observe the manner of bacterial growth. As the results, it was observed that the growth of those bacteria, cultured in the media containing the crude juices of fresh green tea leaves and common ginger root, was poor and these bacteria did not proliferate. On the basis of these observations, the juices of green tea leaves and common ginger root were extracted with alcohol and further fractionated with ether. Next, by mixing these two kinds of fractions to common agar medium and Sabouraud agar medium, Staph. aureus 209-P, oridinal strain, PC, SM-resistant strains of E. coli, Ps. aeruginosa, and Candida family were cultured in order to observe the effects of these fractions on the bacterial growth. The results may be summarized as follows.1. The ether fraction of green tea leaves showed a very marked inhibitory action on the growth of original strains (both Gram positive and negative), Pc-, SM-resistant strains of E. coli, but no inhibitory action on Candida family.2. In contrast to this, the ether fraction of common ginger root demonstrated a relatively weaker inhibitory action than that of green tea leaves, and it did not show any inhibitory action on E. coli and Ps. aeruginosa.