Abstract: In order to degrade soybean dregs in high temperature,thermophilic bacteria were screened from soybean dregs, horse manure, pig manure and domestic sludge. The results showed that 7 thermophilic bacteria strain were gained,which could utilize soybean dregs to grow at 70℃ .Through 16S rDNA identification, they belonged to Geobacillus toebii, Geobacillus sp. , Methylobacterium sp.and Thermus thermophilus,respectively. Among them,Geobacillus toebii (G.T1) was the best for degrading soybean dregs(4.80%).The optimal growth temperature for strain G.T1 was 65℃ ,and optimal initial pH value was 7.5,the strain reached stable growth phase within 24 h.The strain G.T1 was inoculated to soybean dregs (including 5% soybean water sludge) and fermented at 70℃ for 5 d,the carbon-nitrogen ratio (C/N) of the experimental group decreased to 14.43 after 5 d of fermentation,which was lower than the blank(CK).Furthermore,the seed germination index of the experimental group was 135.00%,far higher than that of the CK (86.42%).In addition, as important nutritional indicators of organic fertilizers,the contents of nitrogen,phosphorus and potassium were 27.72,7.69 and 17.92 g/kg in the experimental group,respectively,which were 18.46%,25.04% and 22.74% higher than those in the CK.Therefore,strain G.T1 could not only promote the maturity process of soybean dregs,but also improve the contents of nitrogen,phosphorus and potassium nutrients.

Key words: Soybean dregs, Thermophilic bacterium, Screening, Geobacillus toebii, Organic fertilizer, Aerobic fermentation, Nitrogen,phosphorus and potassium

摘要： 为了在高温条件下降解豆渣，从马粪、猪粪、豆渣以及生活污泥中筛选分离高温菌，初步筛选后获得7株可在70℃条件下利用豆渣生长的细菌，通过16S rDNA鉴定确定其分别属于Geobacillus toebii、Geobacillus sp.、Methylobacterium sp.和Thermus thermophilus4个类别的属种，其中Geobacillus toebii (G.T1)对豆渣的降解率最高(4.8%)。研究表明，高温菌株G.T1的最佳增殖培养条件为生长温度65℃，初始培养基pH值7.5，菌株24 h内可达到生长稳定期。将菌株G.T1转接至豆渣（含5%的黄浆水污泥）中保温70 ℃好氧发酵5 d，结果表明，发酵5 d后，试验组的碳氮比（C/N）降低至14.43，低于空白（CK）；试验组的种子发芽指数为135.00%，远高于CK(86.42%)；此外，作为有机肥重要营养指标的氮、磷、钾元素含量，在试验组中分别是27.72、7.69、17.92 g/kg，比CK分别提升了18.46%、25.04%、22.74%。因此，高温菌株G.T1不仅能加快豆渣的腐熟进程，而且还有助于提高有机肥产品中氮、磷、钾营养元素的含量。

关键词: 豆渣, 高温菌, 筛选, Geobacillus toebii, 有机肥, 好氧发酵, 氮磷钾