Chiang Mai Journal of Science

A new actinomycete species, Streptomyces lichenis LCR6-01T was isolated from lichen collected in Chiang Rai province, Thailand. On the course of screening for antimicrobial activity, the culture broth of strain LCR6-01T exhibited antibacterial activity against Bacillus subtilis ATCC 6633, Kocuria rhizophila ATCC 9341, Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 (inhibition zone 14.7 ± 0.6 - 23.0 ± 0.9 mm). The culture extracts analyzed by liquid chromatographyelectrospray ionization-mass spectrometry (LC-ESI-MS) and the physicochemical properties of secondary metabolites were searched in database. The antibacterial agents were detected as actinomycins which contained 3 analogs of Au7a, D, and D 43β.