油水淹地石油降解菌群的筛选和鉴定及高效菌群的构建

摘要

从油水淹地污染土壤中获得26株石油降解菌,筛选出表面活性剂产生菌1株(H-6)和优势菌6株(H-1、H-17、H-18、H-19、H-20、H-23),结合菌株形态观察、革兰氏染色和16S rDNA序列同源性分析,鉴定表面活性剂产生菌H-6为堀越氏芽孢杆菌(Bacillus horikoshii).以表面活性剂产生菌H-6为中心,再任选3株优势菌株构建石油降解菌群,得到高效石油降解菌群C5(H-1、H-6、H-18、H-19),通过正交试验得到菌群C5各菌种的最佳接种量.结果表明:接种量15％(H-1)、15％(H-6)、20％(H-18)、10％(H-19),温度25℃,石油含量2 000 mg/L条件下,7d时石油降解率达到78.87％.这说明高效降解菌群C5对石油具有较好的降解效果,可应用于油水淹地污染土壤的修复.%One microorganism producing biosurfacant (H-6) and 6 dominant strains (H-1,H-17,H-18,H-19,H-20 and H-23) were screened from 26 strains of oil degradation bacteria obtained from oil-water flooded and contaminated soil.In combination with strain morphological observation,gram staining and 16S rDNA sequence homology analysis,microorganism producing biosurfactant H -6 was identified as Bacillus horikoshii.With H-6 as the center,3 dominant strains were randomly selected to construct oil degradation microbiome colony,high efficient oil degradation microbiome C5 (H-1,H-6,H-18,H-19) was obtained,and the best inoculum sizes of strains in the microbiome C5 were defined by orthogonal test.The results show that 7 d oil degradation rate achieves 78.87％ under the conditions of inoculation size 15％ (H-1),15％ (H-6),20％ (H-18),10％ (H-19),temperature 25 ℃,and oil content 2 000 mg/L.Therefore,high efficient degradation microbiome C5 has good effect of oil degradation,and can be applied to repair oil-water flooded and contaminated soil.