Potensi Actinomycetes Isolat Hutan Mangrove Sicanang Kecamatan Medan Belawan dalam Menghambat Pertumbuhan Methicillin-Resistant Staphylococcus Aureus (MRSA)

Abstract

The utilization of microorganisms as antibiotic-producing agents, especially actinomycetes, is still being developed in line with the increasing need to fight resistance bacteria such as Methicilin-resistant Staphylococcus aureus (MRSA). This study aimed to obtain isolates and to determine the potential of the actinomycetes from Sicanang Mangrove Forest in inhibiting MRSA bacteria. Actinomycetes were isolated from mangrove sediments and water using HVA and SCA media, and then the isolates were characterized macroscopically and microscopically. The antibacterial ability of actinomycetes against the test bacteria MRSA and S. aureus ATCC 25923 was carried out by the agar plug method. The actinomycetes culture extracts with concentrations of 75, 50, and 25% were tested for their inhibitory ability against the test bacteria using the Kirby-Bauer Test method. Potential isolates with the highest inhibitory ability were identified molecularly with 16S rRNA primers. The results of the study obtained a total of 15 actinomycetes isolates from the Sicanang Mangrove Forest area, 14 isolates from sediment and 1 isolate from water. Three actinomycetes isolates,SMC 9, SMC 10, and SMC 12, showed strong antagonistic activity against MRSA and S. aureus ATCC 25923, with the inhibition zone diameters ranging from 17 mm to 23 mm. Comparison of the two actinomycetes culture extracts produced almost the same inhibition zone, ranging from 38% to 87% against MRSA and S. aureus ATCC 25923. The higher the concentration, the zone of inhibition produced increased, but the zone of inhibition obtained was lower than chloramphenicol. The molecular identification of SMC 9 was closely related to Streptomyces rochei,with a similarity percentage of 96.02%.