Aqueous phase biodegradation kinetics of 10 PAH compounds
Aqueous phase biodegradation kinetics of 10 PAH compounds
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DOI：
10.1089/109287503321671410
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发表时间：
2003-05-01
影响因子：
1.8
通讯作者：
Peters, CA
中科院分区：
文献类型：
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作者：
Knightes, CD;Peters, CA
分别研究了 10 种多环芳烃 (PAH) 的生物降解动力学：萘、1-甲基萘、2-甲基萘、2-乙基萘、苊、芴、菲、蒽、荧蒽和芘。实验包括接种多环芳烃降解菌群的需氧、连续混合、间歇式水系统。实验设计和数据的数学解释分离了生物转化的动力学。其他可能影响生物利用度的物理化学过程被消除或独立测量。使用最大似然法对底物和生物量浓度随时间变化的双变量数据集估计模型参数。对于四种多环芳烃：萘、1-甲基萘、2-甲基萘和2-乙基萘，有足够的增长来估计生物量产量系数。对于两种 PAH（萘和 1-甲基萘），估算了莫诺参数 q(max) 和 K-s。对于其余化合物，仅估计一阶速率系数。该联盟能够降解除苊之外的所有多环芳烃。观察到的生物降解率系数与分子量或任何其他化学性质无关。生物量归一化的一级生物降解率系数跨度略小于两个数量级，从0.0255到1.11 h(-1) (mg蛋白质/L)(-1)。这比土壤和沉积物中多环芳烃通常观察到的变化要小得多。这表明，在现场样品中，生物降解率的差异不受生物转化动力学差异的控制。相反，现场生物降解率的差异主要由控制生物利用度的物理化学过程决定，对于不同的多环芳烃，其生物利用度存在显着差异。
Biodegradation kinetics were individually studied for 10 polycyclic aromatic hydrocarbons (PAHs): naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, 2-ethylnaphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene. Experiments consisted of aerobic, continuously mixed, batch aqueous systems inoculated with a PAH-degrading consortium. The design of the experiments and the mathematical interpretation of the data isolated the kinetics of biotransformation. Other physical-chemical processes that may affect bioavailability were eliminated or independently measured. Model parameters were estimated using the maximum likelihood method for a bivariate data set of substrate and biomass concentration over time. For four of the PAHs, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, and 2-ethyl naphthalene, there was sufficient growth to estimate biomass yield coefficients. For two of the PAHs, naphthalene and 1-methylnaphthalene, Monod parameters q(max) and K-s were estimated. For the remaining compounds, only the first-order rate coefficients were estimated. The consortium was able to degrade all p the PAHs except acenaphthene. The observed biodegradation rate coefficients did not correlate with molecular weight or any other chemical property. The biomass-normalized first-order biodegradration rate coefficients spanned a little less than two orders of magnitude, from 0.0255 to 1.11 h(-1) (mg protein/L)(-1). This is much less variation than is typically observed for PAHs in soils and sediments. This suggests that in field samples differences in biodegradation rates are not governed by differences in the kinetics of biotransformation. Rather, the differences in biodegradation rates in the field are primarily governed by the physical-chemical processes that control bioavailability, which differ significantly for different PAHs.