Abstract: In view of the environmental characteristics of low temperature,  low oxygen and oligotrophic groundwater polluted by oil in a certain area of Northeast China,  an experiment on microbial degradation of alkanes was carried out. We determined the nutrient matrix components that stimulated the degradation of indigenous microorganisms through batch static experiments, and investigated the effects of vitamin B (VB),vitamin C  (VC) and vitamin H (VH) on the growth of indigenous functional degrading bacteria and microbial degradation of alkanes.  The experimental results show that VB₁,VB₃,VC and VH have inhibitory effects on the growth of indigenous microorganisms,  VB₆ and VB₁₂ promote the growth of indigenous microorganisms.  The main effects ofvitamins on microbial degradation of alkanes are that VB₆,  VB₁₂ and VH have a promoting effect on the degradation of alkanes to a certain extent,  the degradation rate of alkanes is 73.91%—89.60% after the optimization ofvitamin components, among them,  VB₁₂ has the most obvious promoting effect, and 5 μg/L VB₁₂ has the best  promoting effect on the growth of microorganisms. When the mass   concentration of alkane in  groundwater is 10 mg/L,   the degradation rate of alkanes can reach 91.17% after 7 d of adding  the optimal nutrient matrix of high-efficiencyvitamins under 10 ℃ and low oxygen conditions. The degradation law of alkanes conforms to the second-order degradation kinetic equation, R² is above 0.900. Compared to the non nutrient matrix stimulation,  the relative abundance of alkane-dominant bacteria is significantly increased when the optimizedvitamins effectively stimulate the degradation of alkanes by indigenous bacteria.

Key words: alkane,  , groundwater,  , biological stimulation,  , indigenous microorganisms, vitamin