可将地沟油降解为生物柴油的微生物群落结构和功能研究

t present, China is facing the serious problem of waste cooking oil，which should be disposed in a suitable way. However, The most common way to reuse the waste cooking oil to produce biodiesel is the transesterification, whereas this approach is comparatively expensive and energy-extensive consumption, and may also easily bring secondary pollution . Therefore, in order to find a better method of utilizing waste cooking oil, we try to use the method of soil microbe degradation. Three soil samples were collected respectively in the area contaminated by industrial factories over long time in Lanzhou, the area along the Yellow River and the area near restaurants. Then the microbial communities in soil samples were mixed with waste cooking oil for fermentation, which would not bring secondary pollution and reduce production cost . It was found that new different kinds of alkanes were produced after 90 days' fermentation by soil near restaurants. Additionally, its calorific value had also increased by 17.2% when compared to primitive waste cooking oil. Finally, 454 - pyrosequencing and statistic methods were performed to analyze microbial community composition in soil samples. Organic carbon environmental stress can change the soil microbial community structure near restaurants, in turn, the particular soil community structure formed for a long time also can have a positive response to the soil ecological system and environmental stress, which can degrade the waste cooking oil more effectively. It was found that in response to the organic carbon environmental stress, the content of Proteobacteria in the soil microbial community (60.4298%) was greatly increased, and the content of Magnetospir had reached to 11.2%, which might play an important role in the process of degradation of waste cooking oil. The microbial community selected in our experiment is typical and representative, which might provide a new insight into degrading waste cooking oil to biodesiel.