Isolation And Identification Of Oil-degrading Bacteria And Preliminary Study On The Degradation Characteristics Of Highly Efficient Degradation Bacteria

In recent years,with the development of petroleum and petroleum industry,oil pollution is becoming a serious problem,but a fraction of the oil is very important as oil,is widely used in machinery manufacturing,maintenance and other industries,a large number of oily wastewater produced not only pollute the environment,but also to human beings and other living bring great harm.The separation and domestication of efficient oil degrading bacteria has become an important research direction in the bioremediation of oil polluted environment.In this study,soil samples were collected from long-term oil pollutants by various Hanzhoung tools factory wastewater treatment plant internal activated sludge,preliminary isolation of oil degradation bacteria,further screened oil degrading strains,and the oil degrading strains were studied the degradation characteristics.The results of the study are as follows:(1)A total of 36 strains of biodegradable oil were isolated from oil polluted environment.They were JZ2~JZ4,JZ6~JZ15,JZ17~JZ18,JZ21~JZ24,JZ26~JZ28,JZ30,JZ32,JZ34,JZ36~JZ37,JZ39,JZ41,JZ43~JZ45,JZ47~JZ49 and JZ50.Respectively,From the biochemical tests and 16 S rRNA gene sequence homology analysis,physiological and bacterial morphology observation and of 36 strains of oil degrading strains on the identification results for the Dyadobacter ? Massilia ?Arthrobacter ? Acidovorax ? Pseudomonas ? Ochrobactrum ? Hydrogenophaga ?Perlucidibaca?Rhodobacter?Stenotrophomonas?Sphingobacterium?Paracoccus?Catellibacterium and Shinella zoogloeoides.(2)Determination of 36 strains of oil degradation of oil degradation bacteria screened the rate,screened 4 strains of oil degrading bacteria,respectively.Strain JZ6,JZ18,JZ41,JZ50,7d in culture medium at 30 medium containing crude oil,the oil degradation rate were 42.16%,33.94%,33.75% and 41.89%.(3)The effects of 6 factors,such as different culture time,pH,temperature,initial concentration of crude oil,auxiliary carbon source and auxiliary nitrogen source,on the degradation rate of 4 high efficiency oil degrading bacteria were studied.Theresults show that under the optimum conditions,the highest degradation rate of JZ6 is60.63%,the highest degradation rate of JZ18 is 53.28%,the highest degradation rate of JZ41 is 52.19%,and the highest degradation rate of JZ50 is 56.34%.The selected 4strains of oil degrading bacteria were randomly set up to form compound bacteria group.The K oil degradation rate of the composite bacteria group formed by the combination of strain JZ6,JZ18,JZ41 and JZ50 reached the highest,which was66.87%.4 strains were cultured in different oil components containing twelve alkane,sixteen alkane,eighteen alkane,twenty-two alkane,benzene,naphthalene,pyrene and phenanthrene,and the growth characteristics were observed.The results showed that 4strains could grow with twelve alkane,sixteen alkane,eighteen alkane,benzene and naphthalene as the only carbon source,and JZ6 and JZ50 could also grow in the medium containing pyrene and phenanthrene.GC-MS analysis of oil residue components showed that the main components of crude oil were direct alkanes,followed by branched alkanes,naphthenic hydrocarbons,a certain amount of aromatic hydrocarbons and non hydrocarbons.The degradation rates of JZ6,JZ18,JZ41 and JZ50 to total alkanes were 69.72%,48%,51% and 62.20% respectively,and the degradation rate of direct alkanes was 86.respectively.89%,55.98%,58.42% and89.13% showed that 4 strains had a strong degradation effect on alkanes,of which strains JZ6 and JZ50 had certain degradation effects on other aromatic hydrocarbons except alkanes.