To obtain a bacterial-fungal composite community which can degrade petroleum hydrocarbons efficiently,the preliminary screening was conducted by comparing the degradation rates of individual strains.The two highest-performing bacteria and two fungi were selected for further experiments.Subsequently,a combination of methods including compound formulation and orthogonal design was employed to construct a composite community with optimal petroleum hydrocarbon degradation capability.Molecular identification of the target bacteria and fungi strains was carried out using 16S rRNA and ITS sequencing analysis.Additionally,single-factor experiments were conducted to optimize the cultivation conditions for the composite community.The results demonstrated that the target bacteria and fungi exhibited certain levels of degradation ability towards petroleum hydrocarbons,with degradation rates ranging from 17.19%～52.01%.Notably,the composite community S9,consisting of strains B2,F4,and F5,achieved a degradation rate of 60.34% on the 7th day,surpassing the degradation rates of individual strains by 11.03%,17.94%,and 8.33%,respectively,within the same time frame.The identified strains were B2 (Pseudomonas),F4 (Pseudallescheria boydii),and F5 (Scedosporium apiospermum).After optimizing the cultivation conditions,the composite community S9 demonstrated an 84.37% degradation rate towards petroleum hydrocarbons on the 7th day under the following conditions:inoculation rate of 7.0% (B2 at 2.0%,F4 at 2.5%,and F5 at 2.5%),initial petroleum mass fraction of 1%,temperature of 30 ℃,pH of 7,and agitation speed of 140 r·min-1.This represented a significant improvement of 24.03% compared to the pre-optimized conditions,indicating a remarkable enhancement of degradation capability.
关键词
复合菌群构建/生物降解/石油烃/降解率/条件优化
Key words
Construction of composite microbial community/Biodegradation/Petroleum hydrocarbons/Degradation rate/Condition optimization
维普
万方数据