真/细菌对疏水性有机物的吸附及其表面特性

比较了干燥后真菌Ophiostoma stenoceras LLC和细菌Pseudomonas veronii ZW菌体细胞的比表面积及其对不同疏水性有机化合物吸附性能，并利用BET、红外光谱（FTIR）和X射线电子能谱（XPS）对细胞表面进行了分析.结果表明，真菌LLC和细菌ZW菌体细胞的比表面积分别为15.8m²/g，11.57m²/g，真菌菌体细胞表面介孔较多，可以更有效地吸附有机化合物.在相同的生长阶段，真菌LLC的细胞表面疏水性（cell surfacehydrophobic，CSH）始终要大于细菌ZW；采用α-蒎烯作为唯一碳源培养时，处于对数生长期的真菌和细菌的CSH均有不同提升.干燥后真菌LLC菌体对各疏水性有机化合物吸附能力为乙酸乙酯> α-蒎烯>正己烷，即疏水性相对较低的化合物更容易被吸附.通过XPS和FTIR表征发现菌体LLC吸附有机化合物后，菌体表面的官能团位置未发生明显变化，推测该吸附过程是物理吸附.

Absorption of different VOCs by fungus and bacterium and analysis of cell surface

Adsorption properties to different hydrophobic organic compounds by dried cells, which belonged to the fungus Ophiostoma stenoceras LLC and bacterium Pseudomonas veronii ZW, were compared, and their cell surface hydrophobicity (CSH) were analyzed. The cell surface was characterized by BET, FTIR (Fourier Transform Infrared Spectroscopy) and XPS (X-ray Photoelectron Spectroscopy). Results showed that the specific surface area of Ophiostoma sp. LLC and Pseudomonas sp. ZW was 15.8m²/g and 11.57m²/g respectively. With more mesoporous distributing on their surface, the fungal cells could adsorb organic compounds more efficiently than the bacterial cells. The CSH of the fungus LLC was higher than that of the bacterium ZW when they were at the same growth stage. The CSH of fungal and bacterial cells increased differently during the biodegradation of α-pinene. After being dried, the fungus LLC cells could adsorb different hydrophobic organic compounds followed this order: ethyl acetate > α-pinene > n-hexane, suggesting that low hydrophobic organic compounds could be more easily adsorbed. XPS and FTIR analysis also indicated that the position and the number of functional groups on the surface of the fungal cells did not change obviously before and after the adsorption of organic compounds. These results suggested that the adsorption was a physical process.