高效石油降解菌的筛选及稳定性

为研究不同培养基富集筛选石油降解菌及其稳定性,基于TA克隆分析石油微生物多样性,用不同培养基富集筛选目标石油降解菌,真空冷冻干燥法保藏5 a,研究5 a前后的环境和保藏稳定性。结果表明:TA克隆检测到样品石油中存在8属18种细菌和4种古菌,11个培养基共筛选2属7株细菌,其中高效石油降解菌为XJ09(竿菌属)和XJ15(纤细竿菌p151),降解率分别为54.2％ 和64.5％,XJ02(纤细竿菌)的降解率为34.5 ％;环境模拟实验中,XJ09和XJ15的石油降解率分别为50.8％和53.4％;5 a保藏后,竿菌属降解率降低了2.4％～6.0％,假单胞菌属降解率下降约一半;不同培养基富集培养的纤细竿菌(XJ02和XJ15)的石油降解能力不同;长期保藏和外界环境都会影响竿菌属的稳定性,而对假单胞菌属的影响更大。
The screening and stability of oil-degradation microorganisms, which were enriched from different culture medias, were studied. On the basis of the TA-cloning analyses of the microbial diversities in sampled oils, different media was used to enrich and screen the aimed oil-degradation microorganisms, which were stored for five years using the vacuum freezing drying technology. And the stabilities of circumstance and storage before and after five years were investigated. It is found that there are 18 species of bacteria in eight genera and archaea 4 species from the oil samples based on TA cloning. And 7 species in two genera are screened from 11 media, in which the oil-degradation rates of XJ09 (Bacillus), XJ15 (B. subtilis) and XJ02 (B. subtilis) are 54.2 %, 64.5 % and 34.5%, respectively. In envionment simulations, the degradation rates of bacteria XJ09 and XJ15 are 50.8 % and 53.4 %, respectively. After five years conservation, the degradation rates of Bacillus are declined by 2.4 %-6.0%, while the Pseudomonas sp. is declined by about 50%. The degradation rates of oils by B. subtilis strains (XJ02 and XJ15) screened from different culture media are different. Long-term conservation and external environment conditions could make some influences on the stabilities of Bacillus strains, and Pseudomonas strains are affected more significantly