营养盐对湄洲湾海洋细菌生长及降解石油烃的影响

测定从湄洲湾海域分离的烃细菌在添加和不添加N、P营养盐的海水培养基的生物量及对原油和纯烃的降解作用.结果表明,营养盐对不同菌株的生长及代谢有不同的影响.添加N、P营养盐,试验菌PF-6（Pseudomonas fluorescens 6）的生物量增大,而PA-32（P.aeruginosa 32） 的生物量却减少.在初始原油浓度均为1g/L的摇瓶试验中,添加N、P营养盐培养6d,PF-6菌与PA-32菌的除油率分别为25%及26%,而不添加N、P营养盐时,PF-6菌与PA-32菌的除油率分别为21.4%及36.3%.经气相色谱测定,在以正十六烷和萘两种纯烃组成的培养基,营养盐对两个菌株降解正十六烷的影响仍然不同,但在不添加N、P营养盐时,两个菌株对萘均有较高的降解率.无需添加N、P营养盐能正常生长并降解石油烃的菌株,在海洋油污的生物修复中具有应用前景.

Effect of nutrients on marine bacteria for their growth and the degradation of petroleum hydrocarbon

The oil degrading microbes Pseudomonas fluorescens 6(PF-6) and P.aeruginosa 32(PA-32) were isolated from Meizhou Bay brine sample.Their biomasses and the degradation of crude oil and hydrocarbonwere investigated while nutrients were added in the brine media or not added.The result indicated that N,Pnutrients had different effect on their growth and metabolism.The biomass of strain PF-6 in media added N,P nutrients was more than in media not added any nutrients,but the biomass of strain PA-32 was to the contrary.The bacteria were incubated with same initial crude oil concentration 1g/L in shaking bottle for 6d.The degradation rate of crude oil by PF-6 cultures and PA-32cultures was 25%(w/w) and 26%(w/w) respectively when N,P nutrients were added to the media,but it was 21.4%(w/w) and 36.3%(w/w) respecctively when N,P nutrients were not added to the media.Then the media composed of two hydrocarbons,hexadecane and naphthalene,and analysis of gas chromatography were used to elucidate the metabolim of petroleum compounds.It was found that the effect of nutrients on the two strains for the degradation of hexadecane was the same as of crude oil,but for the degradation of naphthalene was different.Both strain PF-6 and PA-32 had a higher degradation rate of naphthalene without adding any nutrients to the media.The strains that did not require nutrients in brine media promised to be used in bioremediation of oil-contaminated sea water.