Estimation of Biiological Purification Potentials of Petroleum Hydrocarbons in Estuarinrin Sediment of Urban River

城市河流中的河口沉积物含有石油碳氢化合物，这些石油碳氢化合物来自许多不同的来源，如机动车尾气、燃料燃烧产物、空气颗粒物和高沸点石油馏分。利用东京市区多马河河口沉积物，测定了石油烃底物的好氧生物降解率和厌氧生物降解率。将已知数量的石油烃添加到底泥与河底水(沉积物：水，1：1.v/v)混合而成的沉淀物中。我们将石油烃加入试管(100毫升体积)，然后加入10毫升沉淀物泥浆。用乙酸乙酯周期性地从底泥中提取石油烃，然后用FID气相色谱仪或分光光度计测其浓度，在厌氧条件下估计石油烃的最大微生物净化潜力时，固定化培养的降解率好于摇床培养。例如，十六烷30天的降解率，摇动降解率为45%，静止降解率为89%。在十六醇中，摇动15天的得率为31%，静置15天的得率为97%。在对氯苯酚中，摇床为6%，静置25天为94%。在间氨基苯甲酸中，摇床示踪，静置19天可达96%。很明显，这不是由于摇动或与降解细胞接触时间过短而造成的细胞损伤，而是培养条件的适应。沉积物岩心实验表明，氧化底泥中的好氧微生物比厌氧底泥中的微生物更能降解石油烃。在厌氧岩心沉积物中评价了塔玛河水体中十六烷、菲和菲的生物净化潜力。

Estuarine sediments in urban rivers contain petroleum hydrocarbons which are derived from numerous deverse sources such as motor vehicle exhaust, fuel combustion products, airborne particulate matter, and high-boiling temperature petroleum distilllates. We determine the aerobic and anaerobic biodegradation rates of the substrates of petroleum hydrocarbons using estuarine sediment from the Tama River in urban Tokyo.Known amounts of the selected petroleum hydrocarbons were added to a sediment sulurry which was prepared by mixing the sediment with river bottom water (sediment : water, 1 : 1. v/v). We added petroleum hydrocarbons to a test tube (100ml volume), and then added 10ml of sediment slurry. We periodically extracted petroleum hydrocarbons from the sediment slurry using ethyl acetate, and then determined their concentration by FID gas chromatography or spectrophotometer.When the maximum microbial purification potentials of petroleum hydrocarbons are estimated under anaerobic conditions, the degradation ratio by the stationary culture is better than by the shaking culture. For example, the degradation ratio of hexadecane for 30 days is 45% by shaking and 89% by stationary. In hexadecanol, it is 31% by shaking and 97% by stationary for 15 days. In p-chlorphenol, it is 6% by shakin and 94% by stationary for 25 days. In m-aminobenzoic acid, it is trace by shaking and 96% by stationary for 19 days. It is obvious that the reason is not the cell damage by shaking or short contact time between substrate and degrading cell, but adaptaion of cultivation condition. The[ sediment core experiments suggested that aerobic microorganisms in oxidized surficail sediment were more capable of degrading petroleum hydrocarbon than microorganisms in anaerobic sediment. The bio-purification potential of hexadecane, phenanthrene and anthracene in Tama River were evalutated in anaerobic core sediment.