The objective of this study is to isolate and screen new antibiotic producing psychrophilic Actinomycetes and to find out their antimicrobial activity against Streptococcus by agar well diffusion method. The antibacterial activities of isolated actinomycetes were found against S. mutans and S. oralis. A total Six Actinomycetes were isolated from the soil sample through crowded plate technique were subjected to primary screening and identified as Intrasporangium sp., Dactyl sporangium sp., Micromonospora sp., Streptoverticilium sp. and two Streptomyces sp. The bacterial species were isolated from fifty of tooth samples which are collected from the dental hospital and identified as S. mutans and S.oralis. The identification of test pathogenic bacteria is confirmed by hemolytic activity on blood agar plates and biochemical tests. The test organism S. mutans is highly sensitive to Dactylsporangium sp. and the S. oralis sensitive to streptomyces. The Dactylsporangium sp. produce pertinacious substance which is responsible for antimicrobial activity. Other strains are producing non pertinacious substance. This is the first time we report that the species other than Streptomyces showed antibacterial activity against streptococcus associated with dental disease.
A. Raja, P. Prabakaran and P. Gajalakshmi, 2010. Isolation and Screening of Antibiotic Producing Psychrophilic Actinomycetes and its Nature from Rothang Hill Soil Against Viridans Streptococcus sp.. Research Journal of Microbiology, 5: 44-49.