不同氮源对高效稻杆降解复合菌系LZF-12发酵性能的影响

Effect of nitrogen sources on fermentative characteristics of microbial system LZF-12 with high straw-degradation ability

以东北农业大学生物质能研究中心筛选的高效中温稻秆降解复合系LZF-12为研究对象,在35℃、静置培养条件下利用间歇试验,研究尿素、鸡粪及蛋白胨不同氮源对高效稻杆降解复合菌系LZF-12发酵性能的影响。结果表明,浓度0.5%(鸡粪+红糖)为氮源的试验组在发酵终止时稻草分解率可达74%,发酵液的液相末端产物以乙酸为主,乙酸浓度占VFA总浓度90%,有利于提高后续产甲烷相微生物的产气效率和产气能力。鸡粪替代蛋白胨,作为一种廉价的粗氮源,来源广泛且易于获取,可降低稻杆原料降解消化生产沼气的发酵成本。

Batch tests were used to investigated the effect of different nitrogen source such as urea, chicken manure and peptone on fermentative performance of a microbial system LZF-12 with high straw-degradation ability, which has been screened by biomass energy center of northeast agricultural university. The fermentation conditions were controlled at the temperature of 35 ℃ and static culture. The results showed that the experimental group＇s straw-degradation rate of 0.5% nitrogen source （chicken manure＋brown sugar） was 74% at the end of fermentation, and main liquid end products was acetic acid accounted for about 90% of total volatile fatty acid （VFA）, which will increase bio-producing rate and capacity of microbials in follow-up methanogenic phase. As an low-cost crude nitrogen source, chicken manure instead of peptone is a wide range of sources and easy access, this will cut the cost of methane producton using straw to be fermentative materials.