一种假单胞菌SY5降解石油的动力学研究

为了确定石油降解菌对石油污染物的生物降解特性，选用分离得到的一株石油降解菌假单胞菌SY5，对其降解石油污染物的动力学特性进行了研究．研究结果表明，在30℃，pH=7．2的反应条件下，所筛选的SY5菌对石油具有良好的降解能力，降解石油的反应基本符合一级反应动力学，且随石油初始浓度的增大，SY5降解石油的速率减小，降解受到抑制．在生物降解的过程中，SY5的生长曲线具有明显增长和衰减曲线．在生长阶段，产率系数Y值为0．3873．在内源呼吸阶段，衰减系数bd值为0．1805d^-1，SY5菌自身氧化速度比较快．SY5生物降解石油Monod方程的最大比增长速率胁，和半饱和常数Ks分别为1．6d^-1和150mg／L．

Kinetic Characteristics of Degradation of Petroleum by Pseudomonas SY5

In order to decide the biodegradation characteristics of petroleum-degrading strains, the kinetic characteristics of degradation of petroleum pollutants by an isolated pseudomonas SY5 were studied. The conditions of reaction were 30 C and pH 7. 2. The results showed that the isolated pseudomonas SY5 was found good at degrading oil and the degradation reaction behaved as a pseudo-first-order kinetics reaction. With the increase of the initial concentration of oil, the degradation slowed down and was restrained. In the process of biodegradation, the growth curve of SY5 was an obvious growth and decay curve. The yield coefficient（Y） was 0. 3873 mg cell/mg oil in the growth phase. In the endogenous phase, the decay coefficient was 0. 1805 d land the rate of auto-digestion of SY5 was higher. In the Monod expression, the values of the maximum specific rate （μmax） and the half-saturation coefficient （Ks） were 1.6d^-1 and 150 mg/L respectively.