College of Resource and Environment, Northeast Agricultural University, Harbin, 150030, Heilongjiang, China.
College of Resource and Environment, Northeast Agricultural University, Harbin, 150030, Heilongjiang, China.
Colloids Surf B Biointerfaces. 2020 Nov;195:111253. doi: 10.1016/j.colsurfb.2020.111253. Epub 2020 Jul 9.
Biodemulsifiers are widely applied in petroleum processing, mining and petroleum pollution treatment. Polycyclic aromatic hydrocarbons (PAHs) are a common component in petroleum-polluted environments; however, little is known about the mechanism behind the effect of biodemulsifiers on promoting PAH biodegradation. To obtain clear mechanistic insights, the facilitating effects of biodemulsifiers on the bioavailability of phenanthrene (PHE), which is used as a model PAH, and the cell membrane properties of PHE-degrading bacteria Achromobacter sp. LH-1 were researched. The results showed that LH-1 achieved a 96.1 % degradation rate and a 60 % adsorption rate. Biodemulsifiers could encapsulate PHE within micelles to solubilize PHE and increase the cell surface hydrophobicity (CSH) of LH-1 to improve the association of LH-1 with PHE. Furthermore, biodemulsifier molecules can be embedded in the phospholipid bilayer of the LH-1 membrane to increase the permeability and the area of the LH-1 membrane, and they can increase the unsaturated fatty acid contents of the LH-1 membrane to loosen the arrangement of carbon chains, thus further facilitating the uptake of PHE by LH-1 for biodegradation. These results suggest that biodemulsifiers are powerful biological products for increasing the degradation potential of PHE-degrading bacteria in ecosystems, and their application will be important for the economical and efficient bioremediation of PHE-contaminated environments.
生物乳化剂广泛应用于石油加工、采矿和石油污染处理领域。多环芳烃（PAHs）是石油污染环境中的常见成分；然而，对于生物乳化剂促进 PAH 生物降解的作用机制知之甚少。为了获得清晰的机制见解，研究了生物乳化剂对菲（PHE）生物可利用性的促进作用以及 PHE 降解菌 Achromobacter sp. LH-1 的细胞膜性质，PHE 被用作模型 PAH。结果表明，LH-1 实现了 96.1%的降解率和 60%的吸附率。生物乳化剂可以将 PHE 包裹在胶束内以增溶 PHE，并增加 LH-1 的细胞表面疏水性（CSH），从而提高 LH-1 与 PHE 的结合。此外，生物乳化剂分子可以嵌入 LH-1 膜的磷脂双层中，增加 LH-1 膜的通透性和面积，并增加 LH-1 膜的不饱和脂肪酸含量，从而使碳链排列变松，进而促进 LH-1 对 PHE 的摄取进行生物降解。这些结果表明，生物乳化剂是提高生态系统中 PHE 降解菌降解潜力的有力生物产品，其应用对于经济高效地修复 PHE 污染环境将是重要的。
