脱色希瓦氏菌S12的铁还原性能研究

Investigation of the Fe3+ Reduction Properties of Shewanella decolomtionis S12

从印染废水中分离得到了一株具有染料脱色功能的希瓦氏菌脱色新种。该菌能在厌氧条件下利用Fe3+作为末端电子受体获得能量,支持细胞生长。在pH8．0,温度30℃,柠檬酸铁800mg／L,乳酸钠2g／L,酵母抽提物0．5g／L的条件下,培养8h的过程中,菌体细胞量的增长完全与Fe3+的还原发展趋向一致。同时考察了碳氮源、乳酸钠、酵母抽提物、pH值和温度等方面对该菌株的生长和铁还原特性的影响。结果表明,菌体生长以LB为最好,以葡萄糖和乳酸钠为碳源时对铁还原有利。在酵母抽提物浓度4g／L范围内,菌体生长量和铁还原率随着酵母抽提物浓度的提高而提高。当乳酸钠为6g／L时,S12菌体生长量和铁还原率达到最佳。柠檬酸铁浓度为800mg／L时菌体生长量和铁还原率最高。在起始pH6～8的范围内,菌株S12的生长随着pH升高而升高,这也是菌株S12进行铁还原的最佳pH范围。菌株S12在温度范围20℃-40℃内均可生长和进行铁还原,而以30℃时最佳。

A new species of genus shewarella Shewanellade decolorations S12, was isolated from activated sludge of a textile-printing waste-water treatment plant. In the anaerobic condition, S12 could conserve energy for growth by using Fe^3＋ as the terminal electron acceptor. At the optimal condition of pH8, temperature 30℃, ferric citrate 800mg/L, sodium lactate 2g/L, yeast extract 0. 5g/L , the cell growth increased with the raise of the amount of the Fe^3＋ reduction in 8h. The effect of different carbon soucres, nitrogen sources, pH values and growth temperatures on the anaerobic Fe^3＋ reduction of ShewaneUa decolorationis S12 was investigated. LB was favorable for Fe^3 ＋ reduction. Glucose and sodium lactate also were favorable for Fe^3＋ reduction. The cell growth and Fe^3＋ reduction increased with the raise of the amount of the yeast extract from 0 to 4g/L The amounts of the sodium lactate of6g/L and ferric citrate of 800mg/L were suitable for strain S12 growth and Fe^3＋ reduction. In the optimum initial pH value range of 6 -8 for Fe^3＋ reduction, strain S12 growth increased with the raise of the pH value. Strain S12 could growth and reduce Fe^3＋ at the temperature range of 20 -40℃. The best temperature for strain S12 growth and Fe^3＋ reduction was 30℃.