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

城市河流河口沉积物中含有石油烃，这些石油烃来自许多不同的来源，如机动车尾气、燃料燃烧产物、空气中的颗粒物和高沸点的石油烃。以东京市区多摩河河口沉积物为研究对象，将已知量的石油烃添加到沉积物中，并将沉积物与河底水（沉积物：水，1：1）混合，制成沉积物硫浆，测定石油烃底物的好氧和厌氧生物降解速率。v/v）。我们将石油烃加入到试管（100 ml体积）中，然后加入10 ml沉淀浆液。用乙酸乙酯定期提取底泥中的石油烃，用FID气相色谱仪或分光光度计测定其浓度，在厌氧条件下估算微生物对石油烃的最大净化潜力时，静态培养法的降解效果优于振荡培养法。以正十六烷为例，振荡30天降解率为45%，静置30天降解率为89%。在十六醇中，振荡15天，收率为31%，静置15天，收率为97%。对氯苯酚中，振荡法为6%，静置25天为94%。在间氨基苯甲酸中，通过振摇可检出痕量，静置19天可检出96%。结果表明，其原因不是由于振荡或底物与降解细胞接触时间过短而造成细胞损伤，而是培养条件的适应。沉积物柱样实验表明，氧化表层沉积物中的好氧微生物比厌氧沉积物中的微生物更能降解石油烃。采用厌氧柱状沉积物评价了多摩河中十六烷、菲和蒽的生物净化潜力。

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.