健康养殖南美白对虾肠道细菌的抗菌活性

Antibacterial Activity of Intestinal Bacterial in Prawn (Litepenaeus vannamei)

用双层琼脂扩散法检测从健康养殖南美白对虾肠道内分离出的111株菌对8株病原菌的抗菌活性。结果表明:111株菌对白假丝酵母菌,非01群霍乱弧菌,嗜水气单胞菌指示菌无抗菌活性,48.6%的菌株对余下的5株指示菌有抗菌活性,其中气单胞菌属和发光杆菌属对荧光假单胞菌与金黄色葡萄球菌的抑制性最强。各菌属中以气单胞菌属,发光杆菌属的抗菌谱最广,弧菌属、肠杆菌科、黄单胞菌属、芽孢杆菌属、小球菌属次之。土壤杆菌属、棒状杆菌属、黄杆菌属、产碱杆菌属、假单胞菌属和色杆菌属则没有抗菌活性。

111 bacterial strains which were islolated from gut of prawn Litepenaeus vannamei Booen were examined for their antibacterial ability against 8 target strains, using a double-agar layer method. Of the total number of isolates 48.6% of tested strains exhibited antibacterial activity against 5 target strains, including Vibrio harveyi, Vibrio fischeri, Escherichia coli, Psendomonas fluorescens, Staphyloccus aureus, but the activity varied with taxonomic groups and strains of tested bacteria. 3.1% -78.9% of strains belonging to Photobacterium and Aeromonas inhibited the growth of these 5 target strains, 6.3% ～ 56.3% of strains belonging to Vibrios inhibited the growth of Escherichia coli, Psendomonas fluorescens, Staphyloccus aureus , 6.3% ～ 100% of strains belonging to Enterobacteriaceae, bacillus, Micrococcus inhibited the growth of Psendomonas fluorescens. All tested strains exhibited no antibacterial activity agaist Candida adbicans , Vibrio cholerae and Aeromonas hydrophila. The target strains were inhibited maily by the predominant microflora These results may suggest that the antibacterial ability affects by producing antibacterial substances and protect host prawn of fish intestines ： Photobacterium and Aeromonas. the composition of intestinal microflora of the prawn, against pathogenic bacteria, to some extent.