糖脂类生物表面活性剂的特性及其对白腐真菌降解蒽的强化作用

【目的】对铜绿假单胞菌(Pseudomonas aeruginosa)所产生物表面活性剂的稳定性进行分析,考察该生物表面活性剂对乳白耙齿菌F17(Irpex lacteus F17)降解蒽的强化作用。【方法】采用三氯甲烷萃取的方法从铜绿假单胞菌的发酵液中提取生物表面活性剂,采用表/界面张力仪测定该生物表面活性剂在不同条件下的表面张力值,对其进行稳定性研究。在乳白耙齿菌F17降解蒽的过程中加入适量的生物表面活性剂,测定蒽的降解率,探讨其对蒽生物降解的强化作用。【结果】铜绿假单胞菌所产生物表面活性剂的临界胶束浓度为40 mg/L,在15-150°C及pH 6.0-13.0范围内表现出优良的稳定性,对盐浓度的耐受性也很高。在蒽的生物降解过程中,生物表面活性剂能极大地促进蒽的降解,在生物表面活性剂浓度为50 mg/L时,第15天蒽的降解率达到了82.9%。生物表面活性剂在接种乳白耙齿菌F17前1天加入培养基中,能更好地促进蒽的降解。与化学表面活性剂相比,生物表面活性剂对蒽降解的强化作用更显著。【结论】该生物表面活性剂性能优良、稳定性好,能够显著强化乳白耙齿菌F17对蒽的降解,具有良好的应用前景。

Characteristics of glycolipids biosurfactant and its enhancement role in the biodegradation of anthracene by White Rot Fungi

[Objective] We studied the stability properties of the biosurfactant produced by Pseudomonas aeruginosa. And we also investigated the enhancement role of this biosurfactant in the biodegradation of anthracene by Irpex lacteus F17. [Methods] The biosurfactant was extracted using trichloromethane from the fermented broth of Pseudomonas aeruginosa. In order to analyze the stability of the biosurfactant, we determined the surface tension values of the biosurfactant under different conditions using surface/interface tensiometer. During the biodegradation of anthracene by Irpex lacteus F17, we added the biosurfactant to investigate the enhancement role of this biosurfactant. [Results] The result showed that the Critical Micelle Concentration (CMC) of this biosurfactant was 40 mg/L. We observed good stabilities of this biosurfactant in the range of 15?150 °C and pH 6.0?13.0, and this biosurfactant could bear high salt concentration. Using biosurfactant could enhance the biodegradation of anthracene greatly. The degradation rate of 82.9% was obtained after 15 days using 50 mg/L biosurfactant. The biodegradation was enhanced more efficiently when the biosurfactant was added one day before inoculum of degrading strain Irpex lacteus F17. Compared with chemical surfactants, biosurfactant exhibited a more excellent efficacy in enhancing the biodegradation of anthracene. [Conclusion] The excellent surface properties and stabilities and more efficient enhancement in the biodegradation were benificial to the application of biosurfactant in bioremediation.