Exploring the anti-quorum sensing potential of sea anemone bacterial symbionts from Samalona Island (Spermonde Archipelago) in South Sulawesi, Indonesia.

Vannamei shrimp is a promising aquaculture commodity, but presence of Vibrio parahaemolyticus bacteria in cultivation poses a challenge to increasing productivity. Quorum sensing allows bacteria to regulate pathogenicity based on population density. The aim of this study were to screen antiquorum sensing agents that can inhibit bacterial communication, thereby reducing pathogen virulence. The method used in the screening process goes through several stages, such as isolation of anemone symbiont bacteria, screening for inhibition of violacein and antibiofilm production, as well as molecular identification of potential isolates. The highest inhibition of visualization of violacein (diameter of non-purple zone) was shown by SG03 (28.00 mm). Based on the analysis of the inhibition percentage of violacein production and the percentage inhibition of biofilm formation from 105 isolates obtained from 3 species of sea anemones, there are six isolates with inhibition percentage values above 80%, namely HM12, HM19, EQ30, SG03, HM05, and EQ05. Based on 16s RNA identification, six potential isolates were identified as Schouchella sp., Shewanella sp., Halobacillus sp., Pseudomonas sp., Micrococcus sp., and Psychrobacter sp., respectively. Based on whole genome analysis (WGS), isolate HM19 detected the AHL acylase gene (PvdQ), EQ 05 detected the AHL lactonase gene (aiiA), and isolate SG 03 detected the aiiA and PvdQ genes. Six isolates of anemone symbionts have been identified that show the ability to produce anti-quorum sensing agents. This provides potential for effective and environmentally friendly control of pathogenic bacteria.