Isolate Actinomycetes SA32 Origin of Segara Anakan Mangrove Rhizosphere and its Capability in Inhibiting Multi-Drugs Resistant Bacteria Growth

Abstract

The screening of antibiotic-producing actinomycetes from the mangrove environment is increasing to search for bioactive compounds capable of inhibiting the growth of Multi-Drugs Resistant (MDR) bacteria. The research aimed to isolate actinomycetes from mangrove mud rhizosphere in Segara Anakan lagoon that is capable of producing bioactive compounds inhibiting MDR bacterial growth, to characterize phenotypically along with 16S rRNA gene sequence, to cover out inhibition potencies toward MDR bacterial growth, and to characterize antibacterial compounds produced. Isolate actinomycetes SA32 was isolated from rhizosphere mud of Rhizophora mucronata from east Segara Anakan. It showed fragmented aerial mycelium similar to Streptomyces sp. NEAE-102; however, 16S rRNA gene sequence analysis yielded 96% similarity to Streptomyces sp. N56. In antagonism assay, it inhibited the growth of MDR bacteria Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas areuginosa, Enterococcus cloacae and Enterobacter sp. The diffusion antagonism assay results in the highest antibacterial activity against S. aureus with clear zone diameter 20 mm. The result of Minimum Inhibitory Concentration (MIC) assay showed that 20% crude extract has been able to inhibit the growth of MDR bacteria characterized by the decrease of turbidity. The antibacterial compound produced was not known yet but has an Rf value of 0.7-0.9 in the TLC test. Isolate actinomycetes SA32 is potent to be developed as an MDR antibacterial substance source and it is proposed as a new strain of Streptomyces.