An Investigation of Inhibitory Agent against Acid Production of Oral Bacteria

点击翻译按钮获取中文摘要

Inhibitory action of MLI(tentative name) against acid production of oral microoganisms was studied with bacteriocin C3603, iodoacetic acid and azalomycin as controls. MLI was partially purified from culture supernatant of Actinomyces sp. strain. MLI markedly suppressed lactic acid production from glucose by Streptococcus mutans group(serotype a-g) and Lactobacillus casei, and this effect was not due to its antibacterial action. On the other hand, C3603, iodoacetic acid and azalomycin also suppressed lactic acid production, but antibacterial actions were observed. MIL did not suppress productions of formic acid, acetic acid and the other metabolic substances tested by S.mutans group.MLI remarkably inhibited lactate dehydrogenase(LDH) activity depending upon MLI concentration, and nearly 95% inhibition of LDH activity was observed when 2.5 g/ml of MLI was added into the reaction mixture. However, C3603 and iodoacetic acid did not. MLI was analyzed by thin layer chromatography using preparative kiesel gel, and was separated into 4 spots of A,B,C,D showing different RF values, respectively. Only extract from D spot showed inhibition of lactic acid production without antibacerial activity. Then, fraction D was applied to high performans liquid chromatographic column, and 3 peaks were observed. Inhibitory actions of these 3 peaks are under the progress.