Anti-Multidrug Resistance Properties from Sponges Associated Bacteria in Tulamben Bali

Abstract The increasing use of antibacterials reduces the effectiveness of most clinical antibiotics. Multi-drug resistance (MDR) encourages exploration to determine the antibacterial potential obtained from sponges. Sponges are known to harbour bioactive substances with antibacterial potential, offering an alternative to combat MDR pathogens. However, the use of invertebrates from marine has the risk of reducing their population in nature, hence, spongesassociated bacteria that produce secondary metabolites as antibacterials benefit environmental sustainability. This study aims to identify and obtain isolates of bacteria associated with sponges as antibacterial against MDR bacteria from Tulamben waters, Bali. The method in this study used exploratory design. Screening of antibacterial activities employed by plug agar method, microscopic observation using Gram staining, and potential isolate identified by 16S rRNA gene using Polymerase Chain Reaction (PCR). MDR bacteria used in this study consisted of Staphylococcus aureus and Escherichia coli . The results of antibacterial activities from sponges-associated bacteria could inhibit the growth of MDR bacteria. Isolates encoded by BS.SP.09 could inhibit S. aureus with a diameter of a clear zone of 4.10 mm. In comparison, other isolates only inhibit Gram-negative bacteria, such as BL.SP.06 and E.SP.08, against E. coli at 2.50 mm and 6.50 mm, respectively. These potential bacteria BL.SP.06 and E.SP.08 identified as Stutzerimonas stutzeri and Cytobacillus kochii.