Fermentation and Antibacterial Activity of Micromonospora Strains Isolated from Sea Sand

Abstract

Two actinomycetes strains, JSM5-1 and JSM1-3 were isolated from sea sands collected in Chumporn and in Prachuapkhirikhun provinces, respectively. On the basis of morphological, cultural, physiological and biochemical characteristics, and 16S rDNA sequences analyses, they were identified as Micromonospora marina. The antibiotic fermentation of strains in different liquid media, pHs, and temperatures, revealed that those cultivated in glucose soybean (GS) medium at pH 7.0 and at 28 ºC, showed high antibacterial activities. The ethyl acetate extract of fermentation broth showed an antibacterial activity against Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, and Escherichia coli ATCC 25922. Through the use of several chromatographic techniques, the compounds from fermentation broth of JSM5-1 were separated and identified. Furthermore the fermentation and antibacterial activity of JSM5-1 in glycerol molasses peptone (GP) medium was carried out. The extraction and biological activity of the active fractions are described.