野生与养殖银鲳消化道菌群结构中产酶菌的对比分析

实验对野生和养殖银鲳胃、幽门盲囊、前肠、中肠、后肠菌群结构进行了定性对比分析,并对产蛋白酶、淀粉酶、脂肪酶、纤维素酶的菌株进行了鉴定。结果发现,野生和养殖种群的消化道菌群结构存在较大差异,且同一种群消化道各部分之间菌群结构也存在较大差异。尽管养殖和野生银鲳均在幽门盲囊中具有最多的可培养细菌菌株,但野生银鲳消化道内主要菌群为嗜冷菌属(Psychrobacter)和Pseudochrobactrum,养殖银鲳消化道主要菌群为不动杆菌属(Acinetobacter)和假单孢菌属(Pseudomonas),两种群共有细菌仅一株,即Psychrobacter piscatorii strain VSD503,但其分别存在于野生与养殖种群银鲳消化道的不同部位。在产酶菌株筛选中发现,野生银鲳消化道内分离到16株产酶菌,其中44%可培养菌能产蛋白酶,56%能产淀粉酶,11%能产脂肪酶,56%能产纤维素酶,部分菌株可产2株以上的消化酶,其中产3种以上酶的菌株有5株,且产酶量丰富。相对于野生银鲳,养殖银鲳消化道内分离到22株产酶菌,主要以产蛋白酶和淀粉酶为主,70%可培养菌可产蛋白酶,21%可产淀粉酶,仅Bacillus thuringiensis strain VITGS可产纤维素酶,无一株菌产脂肪酶,其中只有Bacillus thuringiensis strain VITGS产3种酶但产酶量相对较少。研究可为银鲳人工养殖中潜在益生菌的筛选提供理论依据。

Comparative analysis of enzyme-producing bacteria in the digestive tract flora of wild and breeding silver pomfret

Abstract: In this study, we qualitatively compared analysis microbial community structure in stomach, pylorus, foregut, midgut, hindgut of wild and farmed silver pomfret (Pampus argenteus), and isolated and identified produced protease, amylase, lipase, cellulase strains. The results showed that, there was a very different the structure of flora between each part of the digestive tract, and microflora populations of the entire digestive tract of the wild and farmed silver pomfret were quite different. The digestive tract flora of the wild silver pomfret mainly included Psychrobacter species , Bacillus species, and the digestive tract flora of the farmed silver pomfret mainly include Acinetobacter species, Pseudomonas species, Psychrobacter species. Psychrobacter piscatorii strain VSD503 was the only kind of bacteria, which did not only exist in the digestive tract of the wild silver pomfret but also exist in the digestive tract of the breeding silver pomfret, but there are different parts. In the experiments of identification of enzyme -producing bacteria , culturable bacteria in the digestive tract of wild silver pomfret yielded protease by 44%, amylase by 56%, lipase by 11% , cellulase by 56%, of which produced more than three enzymes strains had 5 kinds, and rich enzyme production. Relative to the wild silver pomfret, culturable bacteria in the digestive trace of breeding silver pomfret mainly produced protease and amylase, producing protease by 70%, producing amylase by 21%, and only Bacillus thuringiensi sstrainVITGS producing cellulose, no bacterial producing lipase, and only Bacillus thuringiensis strain VITGS can yield three kind of enzymes, but relatively few amount of enzyme production. Analysis shows that the structure of the digestive tract flora affected the species and the activity of digestive enzymes, so producing- enzyme bacterial in the digestive tract of wild silver pomfret as feed additives use for the aquaculture of silver pomfret, which can increase production of silver pomfret.