Chen Lihua, Zhao Shujing, Yang Yiming, Li Li, Wang Dongmei
College of Chemical Engineering, Key Laboratory for Utility of Environment-Friendly Composite Materials and Biomass in University of Gansu Province, Northwest Minzu University, Lanzhou, Gansu 730030, P. R. China.
Center of Experiment, Northwest Minzu University, Lanzhou 730030, P. R. China.
ACS Omega. 2019 Sep 5;4(12):15149-15157. doi: 10.1021/acsomega.9b02045. eCollection 2019 Sep 17.
In this work, four immobilized kinds of mixed microorganisms were prepared by uploading oil-degradation bacteria into the cross-linked biodegradable polyacrylamide and sodium alginate mixture supporting material, which were employed for efficient degradation of oily wastewater. The morphology of immobilized microbial pellets was characterized by scanning electron microscopy after 7d and 14d of duration. The components of residual crude oil were determined by gas chromatography-mass spectrometry, and the microbial degradation and evolution of -alkanes, terpenoids, and steroids were studied. The results show that the oil degradation rate for experimental group I (sample containing 1% crude oil) and experimental group II (sample containing 3% crude oil) reaches as high as 70 and 40%, respectively, after 14d of degradation of saturated hydrocarbon total petroleum hydrocarbons. For different oil components, the degradation degree is in the order of tricycoloditerpanes > homohopanes > norhopanes. The order of the degradation degree of steroids with different carbon atoms is C > C > C. In terms of evolution characteristics, it can be seen from the biological evolution parameters of -alkanes that only a slight degradation for odd-even carbon by biodegradable bacteria was achieved, whereas high degradation for isoprene alkanes was observed. According to the biological evolution parameters of hopane and sterane, hopane C31α β-22S/22S + R and sterane C29α α20S/20(S + R) were all greater than 0.4, that is, they are all strongly degraded by microorganisms.
在本研究中，通过将石油降解菌负载到交联的可生物降解聚丙烯酰胺和海藻酸钠混合载体材料中，制备了四种固定化混合微生物，用于高效降解含油废水。在培养7天和14天后，通过扫描电子显微镜对固定化微生物颗粒的形态进行了表征。采用气相色谱 - 质谱联用仪测定了残余原油的成分，并研究了微生物对正构烷烃、萜类化合物和甾类化合物的降解及演化情况。结果表明，在对饱和烃总石油烃进行14天降解后，实验组I（含1%原油的样品）和实验组II（含3%原油的样品）的石油降解率分别高达70%和40%。对于不同的石油成分，降解程度顺序为三环二萜烷>藿烷>降藿烷。不同碳原子数甾类化合物的降解程度顺序为C > C > C。从演化特征来看，从正构烷烃的生物演化参数可知，可生物降解细菌对奇偶碳的降解程度较小，而异戊二烯烷烃的降解程度较高。根据藿烷和甾烷的生物演化参数，藿烷C31αβ - 22S/22S + R和甾烷C29αα20S/20(S + R)均大于0.4，即它们均被微生物强烈降解。
