Thesis (M.Sc. in Pharm)--Chulalongkorn University, 2000

A managrove actinomycete strain TRA 9839-2, isolated from the managrove forest along the Andaman coast, Trang province was identified as Streptomyces sp. based on morphological, cultural, physiological, and biochemical studies, including cell wall component analysis. The ethyl acetate extract of fermentation broth of TRA 9839-2 exhibited antimicrobial activity against Bacillus subtilis ATCC 6633 and antiviral activity against Herpes simplex virus types I and II. Isolation of the ethyl acetate extract by means of chromatographic techniques yielded four known compounds, including, pyrrole-2-carboxylic acid, trans-cinnamic acid, enterocin, and 5-deoxyenterocin. Structure elucidation of the isolated compounds was performed by extensive analyses of spectral data and comparison with literature data. Examination of biological activities revealed that pyrrole-2-carboxylic acid displayed weak cytotoxicity against KB cell at ED50 = 9.9 mug/ml. Enterocin exhibited weak antiviral activity against Herpes simplex virus type I at the concentration 50 mug/ml, antimalarial activity at EC50 = 9.4 mug/ml, and weak cytotoxicity against KB cell at ED50 = 20 mug/ml. trans-Cinnamic acid showed antitubercular activity at MIC = 200 mug/ml.