罗非鱼主养池塘水体微生物群落对碳源代谢的动态变化

Dynamics of Microbial Community and Its Metabolisms of Different Carbon Sources in Tilapia Ponds

为摸清养殖池塘水体微生物数量的动态变化和微生物群落对不同碳源物质的代谢性能,跟踪研究了罗非鱼主养池塘水体中微生物的数量变动,并采用Biolog ECO微平板法分析微生物群落对糖类、氨基酸、脂肪、代谢中间产物等四类共31种不同碳源的代谢动态变化。结果显示:在5月至10月的整个养殖季中,水体的异养细菌和芽孢杆菌的数量均较稳定,未出现明显的剧烈变化;水体微生物群落对25种碳源物质的利用较平稳,有9种碳源的利用值高于其他22种碳源,包括糖类中的D-甘露醇、N-乙酰-D-葡萄糖氨和D-纤维二糖,氨基酸类的L-天门冬酰胺和L-丝氨酸,脂肪类的吐温40、吐温80、丙酮酸甲酯,代谢中间产物和次生代谢物中的腐胺等。结果表明,在整个养殖季中,池塘水体微生物的数量和群落对碳源的代谢水平总体均处于相对平稳的状态,但微生物群落对不同种类的碳源选择性存在差异。

Heterotrophic bacteria and Bacillus are important indexes of water quality. Their quantity and carbon utilization dynamics were monitored during the tilapia culture season. Biolog ECO microplates were used to analyze microbial utilization dynamics of 31 different carbon sources such as amino acids, saccharides and derivatives, fatty acids and lipids, metabolic intermediates and secondary metabolites. No significant fluctuations of heterotrophic bacteria and Bacillus quantity were observed during May to October. Microbial utilization varied little for most carbon sources during the season. However, nine carbon sources were utilized more than other 22 carbon sources. These were DMannitol, N-Acetyl-D-Glucosamine and D-Cellobiose of saccharides; L-Asparagine, L-Serine of amino acids; Pyruvic acid methyl ester, Tween 40 and Tween 80 of lipids; Putrescine of metabolic intermediates. The results indicate that bacterium quantity and its metabolic activity are both stable, and bacteria have selective metabolisms of different carbon sources.