鸡粪好氧发酵中异养亚硝化细菌的筛选及转化能力

High-efficient heterotrophic ammonia-oxidizing Bacterium-isolation and function during aerobic composting of chicken manure

为从鸡粪好氧发酵过程筛选得到异养亚硝化细菌并测定它们的氮转化能力,在鸡粪与秸秆为堆制原料的发酵过程中的不同温度阶段取样,初步分离异养亚硝化细菌(以乙酰胺为碳和氮源),再通过转化试验测定铵态氮及亚硝态氮,筛选出高效异养亚硝化细菌。结果表明:通过铵态氮转化试验筛选出了15株异养亚硝化细菌,将15株菌生成亚硝态氮的质量浓度统计分析得出其中4株菌与其他菌差异显著(P<0.05),在所测时间及环境内氧化铵态氮和生成亚硝态氮质量浓度平均分别可达100和1 mg/L以上,经鉴定分别为芽孢杆菌、芽孢乳杆菌、棒状杆菌、德克斯氏菌属,均为所筛选菌中的高效异养亚硝化菌。其中芽孢杆菌属的转化能力高于其他属,氧化铵态氮和生成亚硝态氮质量浓度分别可达150、1.5 mg/L,在发酵过程中能发挥硝化作用,提高铵态氮的利用率。4株菌亚硝化作用较强的时段有所不同,但在菌体生长的对数期均出现亚硝态氮迅速增加的现象。

In order to isolate high efficient heterotrophic strains and test their capacity to remove nitrogen, ammoniaoxidizing bacteria were isolated from the composting materials of chicken manure and straw using the medium containing acetamide. The capacity to oxidizing ammonium of the isolates were are then determined through measuring ammonium by digestion method and nitrite by -naphthylamine worldlingo method. The results showed that 4 of the 15 isolates had much higher oxidizing capacity. They are identified as Bacillus, Sporolactobacillus, Corynebacterium and Derxia. At our experimental condition, the quantities of oxidized ammonium and nitrite, changing with incubation time, were were more than 100 and 1 mg/L respectively.