3,5-二硝基苯甲酸降解菌A3的分离及降解特性

Isolation of 3,5-dinitrobenzoic acid degradation bacterium A3 and its degradation characteristics

从硝基苯类化合物废水处理系统中分离到一株3，5-二硝基苯甲酸降解菌株A3，经形态特征、生理生化以及16S rDNA序列分析，初步鉴定为睾丸酮丛毛单胞菌（Comamonas testosteroni）．该菌能以200mg/L3,5-二硝基苯甲酸为唯一碳源，12h的降解率可达95％以上，24h可溶性有机碳（DOC）由72．5mg/L降至10．2mg／L。表明3，5-二硝基苯甲酸被降解矿化而不是被转化成其他有机物．当A3以200mg/L3,5-二硝基苯甲酸为唯一碳、氮源时，将底物转化为一种黄色代谢产物，该产物不易进一步降解．A3降解3，5-二硝基苯甲酸的适宜温度为20-30℃。最适pH值为5-9．

One 3,5-dinitrobenzoic acid-degrading bacterium A3, isolated from waste water treating system of nitrobenzoie compounds, was identified preliminarily as Comamonas testosteroni based on its morphological characters, physiological and biochemical analyses and 16S rDNA series same source analysis. This bacterium degradation rate of 12h could reach above 95%, using 200mg/L 3,5-dinitrobenzoic acid as sole carbon source. 24h dissolved organic carbon （DOC） was reduced from 72.5mg/L to 10.2mg/L, indicated that 3,5-dinitrobenzoic acid was degraded through mineralization but not transformed into other organic matter. But the strain A3 transformed 3,5-dinitrobenzoie acid into a yellow product, cultivated liquor was not discolored all along in the next several days, when 200mg/L 3,5-dinitrobenzoic acid was used as the sole carbon and nitrogen sources, DOC being 56.5mg/L in 24h, indicated that the yellow product was not further degraded easily. The suitable temperature for A3 degradation of 3,5-dinitrobenzoic acid was 20-30℃and pH value was 5-9.