厌氧细菌Acetanaerobacterium elongatum从葡萄糖的产氢特性研究

为了了解影响厌氧发酵产氢细菌Acetanaerobacterium elongatumZ7产氢效率的因素,采用生理学方法对其进行了研究。结果表明:乙醇型发酵菌A.elongatumZ7的最适产氢温度为37℃,最适产氢的起始pH为8.0。该菌发酵葡萄糖和阿拉伯糖产氢的能力较强,氢气产率分别为1.55mol H2/mol葡萄糖和1.50mol H2/mol阿拉伯糖。酵母粉是菌株Z7生长和产氢所必须的生长因子;pH影响菌株的生长和葡萄糖利用率;氢压则影响电子流的分配,从而改变代谢产物乙酸和乙醇的比例;当产氢菌与甲烷菌共培养以维持发酵体系低的氢压时,可使氢的理论产量提高约4倍;培养基中乙酸钠浓度>60mmol/L明显抑制产氢。另外,一个只利用蛋白类物质的细菌能够促进菌株Z7对葡萄糖的利用,进而提供氢产量,为生物制氢的工业化生产提供理论参考。

Hydrogen production from glucose by Acetanaerobacterium elongatum

Studying the possible factors affecting hydrogen production from glucose by Acetanaerobacterium elongatum, an acetateethanol fermenting anaerobe isolated from sludge of wastewater of a papermill. The results revealed that the maximum hydrogen production could be achieved in PYG liquid at 37 degrees C and initial pH 8.0. The strain produced more hydrogen from glucose and arabiose, with the hydrogen yields of 1.55 mol H2/mol glucose and 1.50 mol H2/mol arabiose, respectively. pH and hydrogen partial pressure were the most severe inhibitors in hydrogen production from glucose, by controlling the broth at neutral pH during the fermentation period could increase hydrogen yield twice, concomitantly glucose consumption for 2.8 times. Hydrogen was another inhibitor for fermentative H2 production, and removing hydrogen by cultivating Acetanaerobacterium elongatum Z7 with a H2-trophic methanogen resulted in higher deduced H2 production for about 4 times. Yeast extract stimulated H2 production by stains Z7. Coculturing A. elongatum Z7 and P. acetatigenes TB107, a proteineous-trophic bacterium, increased the conversion of the glucose and thereby increased the H2 production on peptone. Moreover, acetate when at higher concentration ( > 60 mmol/L) in the medium inhibited the hydrogen production by strain Z7.