狐尾藻降解双酚A内生菌的分离鉴定及降解特性

Isolation,Identification and Degradation Properties of a Bisphenol-Adegrading Endophytic Bacterium from Myriophyllum verticillatum L.

该研究从沉水植物狐尾藻中分离筛选到1株可降解环境内分泌干扰物双酚A(BPA)的内生细菌Hu32。通过摇瓶实验进行了菌株降解条件的优化和降解特性的探索,发现菌株降解初始浓度为10 mg/L,BPA的最佳条件为接种量为1%,初始pH值为6.0,温度为25℃。在该条件下,菌株最大生长浓度OD_(600)达到0.22,3 d对10 mg/L,BPA的降解率达到(47.17±1.22)%。经过对其形态特征和16S rRNA基因同源性序列分析,该菌株初步鉴定为类芽孢杆菌属(Paenibacillus sp.)。这是首次从沉水植物中分离到新型可降解BPA的内生菌,有助于了解水生植物对BPA污染水体的修复机制,为进一步阐明水体中BPA的生态归趋奠定基础。

An endophytic bacterial strain Hu32,capable of utilizing Bisphenol A as source of carbon for growth,was isolated from Myriophyllum verticillatum L. The degrading conditions for Strain Hu32 were optimized by tests in shaking flasks and orthogonal tests. The results showed that the optimal conditions for the degradation on BPA at initial concentration of 10 mg/L were 1% inoculum size,initial pH 6.0 and 25 ℃. Based on the above optimal conditions,the maximum optical density（600 nm） of Strain Hu32 increased to 0.22 and（47.17±1.22）% BPA with an initial concentration of 10 mg/L was degraded in three days. Strain Hu32 was preliminarily identified as Paenibacillus sp. based on morphological characteristics and 16 S rRNA gene sequence analysis. This is a novel Bisphenol-A-degrading bacterium isolated from the endophytes of submerged macrophyte. It is helpful to illuminate the fate of BPA in water body and the bioremediation mechanism of toxic pollutants contaminated body by macrophyte.