Affiliation:
1. Department of Aquatic Technology, Fisheries and Marine Science Faculty, Universitas Borneo Tarakan, Tarakan 77115, Kalimantan Utara, Indonesia.
2. Department of Aquatic Resources Management, Fisheries and Marine Science Faculty, Universitas Borneo Tarakan, Tarakan 77115, Kalimantan Utara, Indonesia.
Abstract
In the face of escalating drug resistance amongst microorganisms, the imperative to discover novel sources of antimicrobials is growing. To this end, this investigation delves into the potential of sponge symbiotic bacteria as an alternative source. The aim is to identify and assess the antimicrobial and biocatalytic capacities of symbiotic bacteria located in Xestospongia sp., indigenous to the waters of Derawan Island, Indonesia. Leveraging ½ strength R-2A agar medium, we succeeded in isolating seven symbiotic bacterial strains. The antimicrobial prowess of these isolates was subsequently put to the test against Staphylococcus aureus and Escherichia coli. Five of the seven isolates demonstrated a significant capacity to inhibit bacterial growth, with the Xp-05 isolate being the most effective. Molecular identification revealed that these symbiotic bacteria were part of the Bacillus genus, more specifically Bacillus cereus (Xp-03, Xp-05, and Xp-06) and Bacillus xiamenensis (Xp-01 and Xp-07). Notably, all these isolates were capable of synthesizing protease, amylase, lipase, and cellulase enzymes.. The findings from this research highlight the significant potential of symbiotic bacterial isolates from Xestospongia sponges in Derawan Island's waters for medical and biotechnological applications.