LACTIC ACIDS BACTERIA FROM SHIPWORM (Spathoteredo obtusa) AND ITS INHIBITION CAPASITY TO SHRIMP PATOGEN Vibrio parahaemolyticus.

Author : Mohamad Fadjar, Paul Kemp, Sri Andayani, Cucun Herlina, Vira DwiArima Putri

Abstract : Shipworms (Spathoteredo obtusa) are marine bivalves known for their wood-boring abilities and pivotal ecological role in decomposing submerged wood and produce secondary metabolites with potential applications in aquaculture and marine biotechnology. Despite their ecological importance, the microbial symbionts and bioactive compounds associated with S. obtusa remain poorly understood. This study aimed to explore the microbial diversity and secondary metabolite composition of S. obtusa collected from Probolinggo and Sidoarjo East Java to evaluate microbial diversity and metabolite composition. The methods used were descriptive and experimental. Biochemical tests included Gram staining, Hydrogen Sulfide (H2S), Indole, Motility, Methyl Red, Voges Proskauer, and Simmons' Citrate. This study used six bacterial isolates in the biochemical tests, namely three isolates from Sidoarjo and three isolates from Probolinggo. The bacterial antagonism test used the Kirby-Bauer disc method and measured the inhibition zone around the paper disc. Two treatments were used: bacterial isolates from the gills of Sidoarjo and Probolinggo, with the addition of 20 µL of positive (chloramphenicol) and negative (aquadest) controls. The biochemical test results indicated that the six isolates belonged to the Enterococcus genus of LAB. Based on the antagonism test results, Enterococcus sp. was able to inhibit Vibrio parahaemolyticus , shrimp pathogen bacteria. The average values for both isolates were 7.65 mm for Probolinggo and 6.59 mm for Sidoarjo, which are considered moderate based on their inhibitory strength

Keywords : Shipworms, identification, microbial symbiosis, bioactive compounds, V. Parahaemolyticus

Conference Name : International Conference on Marine Microbiology and Ecosystem Health (ICMMEH-26)

Conference Place : Frankfurt, Germany

Conference Date : 19th Jun 2026