Abstract: In order to increase endospore amount at shake flask fermentation of Bacillus subtilis strain J530 which could produce urease inhibitors,and explore its reduction effect on ammonia emission from chicken manure,the fermentation conditions of this strain were optimized by single factor and orthogonal experiments,the bacterial agent was activated and then joined to fresh chicken manure,and the changes in the number of Bacillus subtilis,urease activity,ammonia release,ammonia nitrogen content,pH value,urea content,uric acid content and total nitrogen content were measured at 5 days after fermentation.The results showed that the optimal conditions for endospore production by shaking flask fermentation of strain J530 were as follow:Corn flour of 1.5%,soybean meal of 1.5%,MgSO₄·7H₂O of 0.3%,Na₂HPO₄of 0.2%,KH₂PO₄of 0.2%,bottle volume of 50 mL(Erlenmeyer flask 250 mL),initial pH value of 8.0,the inoculum amount of 4.0%,the culture temperature of 37℃ ,the shaker speed of 150 r/min,and the ferment time of 36 h. After optimization,the endospore content of fermentation broth increased by 20.32 times.Compared with the control group,the spore content in the test group increased by 60.29 times(P<0.01).The urease activity,ammonia release amount and ammoniacal nitrogen content were reduced by 80.78% (P<0.01),67.78%(P<0.01) and 48.57% (P<0.01).The pH value in the test group decreased by 1.35(P<0.05).The urea content,the uric acid content and the total nitrogen content increased by 24.79%(P<0.05),0.91% (P>0.05) and 8.53%(P>0.05).In conclusion,the optimal conditions for endospore production of strain J530 in shake flask fermentation were obtained,and J530 had a significant effect on reducing ammonia emissions from chicken manure.

Key words: Bacillus subtilis, Herment conditions, Optimization, Urease activity, Ammonia emission reduction, Chicken manure

摘要： 为提高产脲酶抑制剂枯草芽孢杆菌J530菌株摇瓶发酵时的产芽孢量，并探索J530菌株制备的菌剂对鸡粪便的氨减排效果，利用单因素和正交试验对该菌株摇瓶发酵条件进行优化，将该菌剂活化后接入新鲜鸡粪，测定发酵5 d后芽孢杆菌浓度、脲酶活性、氨气释放量、氨氮含量、pH值、尿素含量、尿酸含量和总氮含量的变化。结果表明，J530菌株摇瓶发酵产芽孢的最优条件：玉米粉1.5%、黄豆饼粉1.5%、MgSO₄•7H₂O 0.3%、Na₂HPO₄ 0.2%、KH₂PO₄ 0.2%、装液量50 mL（250 mL锥形瓶）、初始pH值8.0、接种量4.0%、培养温度37 ℃、摇床转速150 r/min、发酵时间36 h。优化后，发酵液芽孢浓度提高了20.32倍。鸡粪应用试验中，与未接种菌剂的对照组相比，试验组的芽孢杆菌浓度提高了60.29倍（P<0.01）；脲酶活性、氨气释放量和氨氮含量分别降低了80.78%（P<0.01）、67.78%（P<0.01）和48.57%（P<0.01）；pH值降低了1.35（P<0.05）；尿素含量、尿酸含量和总氮含量分别提高了24.79%（P<0.05）、0.91%（P＞0.05）和8.53%（P＞0.05）。综上，研究确定了J530菌株摇瓶发酵产芽孢的最优条件，并证明J530菌剂具有显著的降低鸡粪便氨排放的效果。

关键词: 枯草芽孢杆菌, 发酵条件, 优化, 脲酶活性, 氨减排, 鸡粪