一株大蒜素降解菌的分离与鉴定

Isolation and characterization of an allicin-degrading strain

摘要:

【目的】解决大蒜废水难以生化处理的问题，筛选能够降解大蒜素的细菌，并对其生化特性进行分析。【方法】通过16S rRNA基因测序，对大蒜废水沉积物进行细菌多样性分析，发现其中有多种大蒜素耐受菌；通过富集培养与划线分离大蒜素降解菌，并进一步分析其最适生长和大蒜素降解条件。【结果】得到一株大蒜素降解菌(JX6-2)，能够以大蒜素为唯一碳源生长(50?300 mg/L)，将大蒜素彻底降解。其最适生长温度和降解大蒜素温度均为35 °C，最适pH值在中性左右，添加葡萄糖对大蒜素降解没有明显影响。【结论】分离得到了一株大蒜素降解菌，分析了其生长和降解特性，为生化方法处理大蒜素废水提供了新菌种。

Abstract:

[Objective] The anti-microbial ability of residual allicin in garlic wastewater results in its low bio-degradability. To resolve this problem, this paper tried to isolate the allicin-degrading bacteria and to further analyze its degradation character. [Methods] We inspected the bacterial diversity in the polluted sediment of garlic wastewater by 16S ribosomal RNA gene sequencing, and 16 microbial species were found which suggested allicin degradation bacteria might be included. Next, our research was focused on enrichment, separation and characterization of the allicin-degrading strain. [Results] An allicin-degrading strain JX6-2 was isolated from the sediment of allicin wastewater, and identified as Weissella. The strain could use allicin as the only carbon source and grow on the range of allicin concentrations (50 to 300 mg/L). The optimal pH and temperature for allicin degradation were determined to be 7.0 and 35 °C, respectively. The presence of glucose as an additional carbon source (up to 1 000 mg/L) had no adverse effect on bacterial growth and allicin degradation. [Conclusion] We have isolated an allicin-degrading strain and optimized its degradation conditions. It has a potential to be applied in the practical treatment of aniline-containing wastewater.