Isolation And Identification Of Oil Degrading Fungus, As Well As Analysis Of The Oil-contaminant Degradation

With the development of morden petroleum industry,the pollution caused by oil becomes more and more serious.The oil pollution not only destroys the environmental ecological balance but also threaten the human's health,so more and more countries pay attention to the oil pollution problem and make great efforts to find a better treating method to resolve it.Microbiological remediation technology has been considered a sate,economical and reliable method to remediate oil in soil and oil-degradating microorganisms play a important role in the technology.Bioremediation is a kind of remedying technology for the ecological system of oil-contaminated soil by making use of the degradation function of microbes. The cost is from about one fifth to one third compared to the traditional physical and chemical methods. Due to its advantages in a low cost, free additional pollution and moderate conditions, the method has been studied and developed extensively in the world.In the first chaper of the paper,a review about the components of oil,the oil pollution ways to soil,the oil-degradating microorganisms,the end-result of oil in the soil,the methods for oil remediation,and the factors affecting the degradation rate has been shown to the readers.A series laboratory studies have been conducted to isolate and purify a stable growth of three fungal strains,and their determination for growth and physical and chemical properties;by ITS sequence analysis of the three fungal strains were identified;oil as the sole carbon source,the three fungi in liquid medium and soil degradation effects of the oil were determined.Daqing oil field by oil-contaminated soil fungi screened to select three fast-growing stable of fungal strains, respectively, numbered as No.3 strains,4 strains and 6 strains. Three strains of the physical and chemical properties analysis found that three strains have the characteristics of alkali resistance, and in acidic conditions, can not grow fast. In the fungal growth process of an appropriate increase in temperature will restrain the growth of mycelium.Three strains for molecular identification get results as follows:Fusarium oxysporum(Num.3); Fusarium solani f. radicicola(Num.4);Mucor circinelloides f. circinelloides(Num.6).Three fungus can degrade the oil of good results.Num.3 Fusarium oxysporum liquid medium degradation efficiency is 79.07%,and 68.14% under the soil conditions; Num.4 Fusarium solani f. radicicola liquid medium degradation efficiency is 75.93%, and 71.51% under the soil conditions; Num.6 Mucor circinelloides f. circinelloides liquid medium degradation efficiency is 71.48%,and 64.51%%under the soil conditions; mix bacteria liquid medium degradation efficiency is 74.65%, and 68.77% under the soil conditions.