title: Effect of monorhamnolipid on the degradation of n-hexadecane by Candida tropicalis and the association with cell surface properties.
abstract: The effect of monorhamnolipid (monoRL) on the degradation of n-hexadecane by Candida tropicalis was investigated in this study. The concentration of hexadecane, cell growth, cell surface hydrophobicity (CSH), cell surface zeta potential (CSZP), and FT-IR spectra of cellular envelope were tested to determine the mechanisms. MonoRL at the initial concentrations of 11.4, 19, and 38 mg/l improved the degradation of hexadecane, and 19 mg/l was the best concentration. However, 114 mg/l monoRL suppressed the biodegradation probably because of the reduced bioavailability of hexadecane caused by the micelles. The presence of monoRL changed the cell surface properties, which was demonstrated by the increased CSH, the increased CSZP, and the changed FT-IR spectra of cellular envelope at 680 and 620 cm(-1). The changes of cell surface properties may be a reason for the enhanced biodegradation of hexadecane by the yeast. The results indicate the potential application of monoRL in the bioremediation of hydrocarbons.
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, People's Republic of China. zgming@hnu.cn
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Liu
authors.forename: Hua
authors.initials: H
authors.lastname: Zhong
authors.forename: Jianbing
authors.initials: J
authors.lastname: Li
authors.forename: Xingzhong
authors.initials: X
authors.lastname: Yuan
authors.forename: Haiyan
authors.initials: H
authors.lastname: Fu
authors.forename: Ying
authors.initials: Y
authors.lastname: Ding
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Meifang
authors.initials: M
authors.lastname: Zhou
mesh_terms: D000473:Alkanes / Q000378:metabolism*; D001673:Biodegradation, Environmental; D041022:Candida tropicalis / Q000737:chemistry / Q000378:metabolism*; D006017:Glycolipids / Q000378:metabolism*; D057927:Hydrophobic and Hydrophilic Interactions; D013499:Surface Properties
chemical_list: D000473:Alkanes; D006017:Glycolipids; C418382:rhamnolipid; C007932:n-hexadecane