Shrimp culture process of Litopenaeus vannamei could not be separated from the disease threats. Vibriosis is the main cause of a decrease in aquaculture production. Vibrio harveyi is a pathogenic bacteria that can caused high mortality and Vibro parahaemolyticus can also cause massive financial losses in shrimp culture. The use of antibiotics to control vibriosis, however, has a negative impact. For example, it resulted in the shrimp resistance to pathogenic bacteria. The potential of bacteria that are symbiotic with nudibranchs as anti Vibrio spp. has not been reported yet. The aim of this experiment was to examine the presence of bacterial symbiont in a nudibranch to inhibit or stop the growth of V. harveyi. Antibacterial activity test was done by the overlay method. The tested pathogenic bacteria were used V. harveyi and V. parahaemolyticus. Then the active bacteria were identified by morphological and molecular using 16S rRNA gene sequence. Isolation of bacterial symbiont in Nudibranch revealed 144 isolates. From those isolates only one isolate (SM-N-3(2)/7) was identified as having the ability against V.harveyi and V. parahaemolyticus. The isolate was gram negative rod bacteria. Based in molecular identification using 16S rRNA it was closely related to Pseudoalteromonas piscicida strain NBRC (99%).

南美白对虾养殖过程离不开病害威胁。弧菌病是水产养殖产量下降的主要原因。哈维弧菌是一种病原菌，可导致高死亡率，副溶血性弧菌也可在养虾业造成巨大的经济损失。然而，使用抗生素来控制弧菌病会产生负面影响。例如，它导致了虾对病原菌的抵抗力。与裸鳃类共生的细菌作为抗弧菌属的潜力。尚未报告。本实验的目的是检查海蛞蝓中细菌共生体的存在，以抑制或阻止哈维氏弧菌的生长. 抗菌活性试验采用叠加法。测试的病原菌使用哈维弧菌和副溶血弧菌。然后利用16S rRNA基因序列对活性菌进行形态学和分子学鉴定。Nudibranch 中细菌共生体的分离揭示了 144 个分离株。从这些分离物中，只有一种分离物 (SM-N-3(2)/7) 被鉴定为具有抗哈维氏弧菌和副溶血性弧菌的能力。分离物是革兰氏阴性杆菌。基于使用 16S rRNA 的分子鉴定，它与Pseudoalteromonas piscicida菌株 NBRC (99%)密切相关。