新型复合生物乳化剂的性质及其在多环芳烃降解中的作用

Character of A New Bioemulsifier and Its Influence on Biodegradation of Polycyclic Aromatic Hydrocarbons (PAHs)

对一株能利用多种石油烃的Em1菌株产生的生物乳化剂 ,采用柱层析方法进行分离纯化 ,其表面活性组分存在于氯仿、甲醇、浓盐酸混合物 (V V V =5∶1∶0 0 1 )的洗脱液中 ,挥发洗脱溶剂即为纯化的生物乳化剂。该生物乳化剂可使蒸馏水的表面张力由 72mN m降至 30mN m ,其临界胶团浓度 (CMC)为 75mg L。它不含糖类、蛋白、中性脂、磷酸基团和α 氨基酸 ,采用红外光谱 (IR)、气质联用 (GC MS)和核磁共振 (NMR)测定其化学组成和结构 ,表明其主要由十六烷酸、脂肪醇类、酯类和脂肪酰胺类等组成 ,这些物质的协同作用是该生物乳化剂高表面活性的关键。该生物乳化剂可明显促进菌株对多环芳烃的降解作用 ,可将降解率提高 2 0 % ,其促进降解的机制主要是提高多环芳烃在水中的溶解度 ,平均可提高约 1

A bioemulsifier was purified by column chromatograph, which was produced by Rhodococcus ruber strain Em1 that could degrade various petroleum hydrocarbons. Bioemulsifier exists in the fraction washed by CHCl 3-CH 3OH-HCl (V/V/V=5∶1∶0 01). This bioemulsifier could decrease the surface tension of water from 72 mN/m to about 30 mN/m, the critical micelle concentration (CMC) of the bioemulsifier was 75 mg/L. This bioemulsifier did not contain saccharide, protein, neutral fat and α-amino acid, and it was verified that the cooperation of hexadecanoic acid with fatty alcohol, ester and fatty acyl amine should mainly answer for the surface activity of the bioemusifier by the results of infrared spectra, gas chromatograph-mass spectra and nuclear magnetic resonance. It was also demonstrated that the bioemulsifier could obviously improve the degradation of polycyclic aromatic hydrocarbons (PAHs) by stain Em1 and remarkably increase solubility of PAHs in water, the average increscent multiple was about 10