Optimization of Growth Media, Antibiofilm Evaluation and Taxonomic Identification of Symbiotic Bacteria from the Sea Anemone Heteractis magnifica

Abstract

Antibiotic resistance and biofilm-associated infections remain critical global health challenges. Its responsible for up to 65% of infections in humans and have adaptive resistance 10–1000 times higher against conventional antibiotics. Thus, development and finding of new antibiofilm agent is needed. Marine bacteria, particularly symbion of anemone Heteractis magnifica, offer promising yet underexplored sources of bioactive componds as antibiofilm agents. This research aimed to optimize the growth condition, assess the antibiofilm activities and identify potential strain of symbiotic bacteria from H. magnifica in Samalona Island, Indonesia. The growth of two bacterial isolates (CM01 and CM03) were optimized, revealing that CM01 grew best in TSB with 2%NaCl and 2% peptone at 37°C for 48 h incubation, while CM03 exhibited optimal growth in Zobell medium with 2% peptone at 28°C for 48 h. Secondary metabolites produced under these conditions were tested against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. The 50-hour metabolite of CM03 demonstrated the strongest and broadest antibiofilm activity. Due to its antibiofilm potential, strain CM03 was subjected to genomic characterization using 16S rRNA PCR method. Phylogenetic analysis identified the isolate as Halalkalibacter okhensis. These findings indicate that symbiotic bacteria of H. magnifica, particularly H. okhensis CM03, represent promising candidates for the discovery of new antibiofilm agent.