Pang Sing Tung, Julian Ransangan, Hatai Kishio
Microbiology and Fish Disease Laboratory, Borneo Marine Research Institute, University Malaysia Sabah.
Biocontrol Sci. 2019;24(1):1-11. doi: 10.4265/bio.24.1.
The prevalence of antibiotic resistant bacteria in aquaculture has reached alarming proportions and intensified the search for microbe derived antimicrobial compounds. This study isolated bacteria from the intestine of Sagor catfish (Hexanematichthys sagor) and screened it for antagonistic properties. Five out of 334 bacterial isolates inhibited growth of fish pathogens. The 5 bacterial strains included relatives of Shewanella haliotis, Myroides odoratimimus, Vibrio harveyi, Vibrio alginolyticus and Alcaligenes faecalis. The growth profiles and probiotic properties of these bacteria were examined. The results showed that the isolate 9 (3) 7.5.2.1, whose closest relative was S. haliotis exhibited growth and probiotic advantage compared to the other bacterial strains, such as highest doubling time and the ability to survive at all experimental temperatures (18 to 60℃) , and bile concentrations (0.01 to 1.00%) and pH (pH2 to 9) . While the bacteria with probiotic properties were successfully isolated. Further study is necessary to examine the efficiency of the probiotic candidate bacteria in boosting fish immunity against pathogens.
水产养殖中抗生素耐药细菌的流行已达到惊人的比例，并加剧了对微生物源抗菌化合物的寻找。本研究从萨戈尔鲶鱼（Hexanematichthys sagor）的肠道中分离细菌，并筛选其拮抗特性。334株细菌分离物中有5株抑制了鱼类病原体的生长。这5株细菌菌株包括哈氏希瓦氏菌（Shewanella haliotis）、恶臭拟杆菌（Myroides odoratimimus）、哈维氏弧菌（Vibrio harveyi）、溶藻弧菌（Vibrio alginolyticus）和粪产碱菌（Alcaligenes faecalis）的亲缘种。对这些细菌的生长特性和益生菌特性进行了研究。结果表明，与其他细菌菌株相比，亲缘关系最接近哈氏希瓦氏菌的分离株9(3)7.5.2.1表现出生长和益生菌优势，如最高的倍增时间以及在所有实验温度（18至60℃）、胆汁浓度（0.01至1.00%）和pH值（pH2至9）下存活的能力。虽然成功分离出了具有益生菌特性的细菌，但有必要进一步研究益生菌候选细菌在增强鱼类对病原体免疫力方面的效率。
