Enhanced Biodegradation Characteristics of Oil Degrading Strains Supplemented with Nitrogen Source

Abstract:

The paper studies the effects of adding nitrogen source on single strains and mixed strains isolated from seawater of Tianjin, Dalian and Shanghai. The results show that adding nitrogen source promotes the biodegradation of diesel oil and enhances the cell surface hydrophobicity. NH4NO3 is the optimal nitrogen source to T4 while NaNO3 the optimal to D3 and R4 as well as the optimal ρ(C)/ρ(N) to the three strains is 20:1.There is a close relationship between biodegradation and cell surface hydrophobicity. It is found that there is a lipopeptide structure in the metabolin of petroleum degrading bacteria and the hydrophobic group increases significantly with the addition of nitrogen source. Adding nitrogen source improves biodegradation rate of microbial consortium greatly, in the meantime,T4/R4, T4/D3, T4/R4/D3 show the synergistic degradation.

Key words:oil degrading strains; nitrogen source; degradation rate; mixed strains