畜禽粪便堆肥高温保氮菌Aliibacillus thermotolerans BM62的筛选及复壮

氨氧化细菌可以将NH3氧化成NO2-,从而减少堆肥过程中的氨挥发,是畜禽粪便堆肥中的理想保氮微生物。本实验在堆肥高温期样品中分离得到一株高温微好氧氨氧化细菌,经鉴定此菌株为芽孢杆菌科(Bacillaceae)的一个新属,命名为Aliibacillus thermotolerans BM62。在后续研究中由于反复迭代等原因,发现其氨氧化能力有所衰退。菌株BM62可适应堆肥高温阶段微好氧环境进行氨氧化作用,该特性使其在堆肥保氮中具有较高的理论研究价值和实际生产意义,因此对该菌株氨氧化能力的复壮研究十分必要。本实验以Aliibacillus thermotolerans BM62为研究对象,以来源环境堆肥为基础,添加不同营养因子(牛肉膏、蛋白胨)作为复壮培养基,考察不同复壮载体对菌株复壮效果的影响。实验结果表明,菌株BM62在不加任何外源有机物的堆肥原环境复壮培养基的复壮效果最佳,经复壮培养后,该菌株氨氧化活性为34.7~36.5 mg/L,与其退化前氨氧化能力(35.0 mg/L)相当。

Screening and rejuvenation of nitrogen-resistant thermophilic bacteria Aliibacillus thermotolerans BM62

Ammonia-oxidizing bacteria(AOB)are of great importance as these nitrifiers oxidize NH3 to NO2-and reduce the loss of NH3 by volatilization in thermophilic phases during composting,making them ideal potential organisms for animal waste disposal.A thermophilic and micro-aerobic AOB was screened from the sample of high temperature composting.Data from this polyphasic taxonomy study suggested that strain BM62 should be classified as the type species of a new genus within the family Bacillaceae for which the name Aliibacillus thermotolerans is proposed.However,its ammonia oxidation capability declined significantly due to repeated iterations and other reasons.Aliibacillus thermotolerans BM62 can carry out ammonia oxidation in the micro-aerobic environment during the high-temperature stage of composting.This characteristic makes it highly theoretically valuable and practically meaningful for nitrogen conservation in compost,therefore,it is necessary to study the rejuvenation of the ammonia oxidizing ability of strain BM62.So,strain BM62 was selected as the research object,and different nutrient factors(beef extract,peptone)were added to the source environment compost medium as the rejuvenation medium.The purpose of this paper was to investigate the effects of different rejuvenation medium on ammoxidation ability rejuvenation of the strain.The results showed that strain BM62 had the best rejuvenation effect in composting environment rejuvenation medium without any exogenous organic matter.After rejuvenation culture,the ammoxidation activity of the strain BM62 was 34.7~36.5 mg/L,which was equivalent with the ammoxidation capacity(35.0 mg/L)before it was degraded.