| In the process of agricultural development,pesticides and fertilizers are widely used.Although they play an important role in promoting agricultural production,over time,accompanying problems such as soil nutrient imbalance,loss of fertility,and destruction of the ecological environment have gradually been exposed.Nowadays,the concepts of organic agriculture and organic food have been gradually popularized.Microbial agents can play a significant role in the production and application of organic agriculture.These effects include improving the degradation efficiency of organic matter,repairing soil,reducing the occurrence of pests and diseases,promoting crop growth,and increasing yield and income.The use of microbial inoculants helps to control food safety from the source and promote the comprehensive utilization of food processing waste.However,there are still some defects in the developed microbial agents,such as low degradation efficiency,incomplete functions and poor stability of organic matter.Therefore,it is necessary to develop microbial agents with various functions,stable performance and high efficiency.In this study,abilities to degrade organic matter efficiently were seem as the most important screening standard,supplemented by the control of blue mold rot in pear fruit.Safe and efficient new strain was found and further investigated.The researches can provides new usable strains for future product development and lays the foundation for theoretical research.The main results obtained in this study are as follows:1.According to the result of evaluation of organic matters degradation ability,the inhibition ability of blue mold rot of Penicillium expansum in pear fruit,and the safety,18 strains of bacteria were screened to have the degradation ability of organic matter,5of them were capable to degrade cellulose,starch and protein.6 strains can directly inhibit blue mold rot of Penicillium expansum in pear fruit.Based on all the evaluation results,the best-functioning strain Anoxybacillus sp.（CICC 20647）was selected for subsequent researches.2.The addition of glucose,sorbose,cellobiose,galactose,fructose,mannose and xylose in liquid fermentation medium can simultaneously promote the production of extracellular cellulase,amylase and protease of Anoxybacillus sp.（CICC 20647）.However,different additives had different efficiencies in promoting enzyme production,and the maximum enzyme activity and time of its appearance were different.In the solid-state fermentation medium with wheat bran,soybean meal and syrup as the main raw materials,adding 0.05%Tween-80 can effectively improve the cellulase production of the strain,which is 1.7 times of the enzyme activity of the control group.3.Anaxybacillus sp.（CICC 20647）was used to treat kitchen waste,and compared with other strains and commercial microbial agents.After 7 days of treatment,there was no significant difference in the quality of different groups.The changes of soluble sugar and soluble protein were different due to the different metabolism of the strain,and the EC value increased.From the observed degradation degree of raw materials,Anoxybacillus sp.（CICC 20647）and commercial microbial agent lvlong EM had the best degradation effects on kitchen waste with the most complete degradation degree and the lowest E4/E6 ratio.Overall,Anaxybacillus sp.（CICC 20647）has a good treatment effect and application potential.4.Developed a cost-effective culture medium of Anoxybacillus sp.（CICC 20647）for industrial use.The optimized medium was formulated as 1 g Na2HPO4,1 g KH2PO4,0.05 g Mg SO4,3 g Na Cl,0.05 g Ca Cl2,11.44 g wheat bran powder,4.92 g soybean meal,and 1 L distilled water at p H 7.12.The maximum biomass attained was 1.57±0.153×109 CFU/m L.The optimal culture conditions were determined to be a 5%inoculation level,50°C culture temperature,25 m L filling volumes in 250 m L flasks,and 180 rpm shaking for 24 h.The acute toxicology test of zebrafish evaluated the optimized fermentation culture as safe.5.The complete genome of strain Anoxybacillus sp.（CICC 20647）was sequenced using Oxford Nanopore Technologies（ONT）as the third-generation sequencing technology.The predicted genome length was 3876788 bp,and the predicted coding gene length was 3175653 bp.The number of coding genes was 3747,and the GC content was 42.45%.Compared with the Nr database,61.50%of the genes were annotated to the Anoxybacillus tepidamans strain.The genome sequences were compared with databases such as GO,COG,KEGG,CAZy,MEROPS,etc.,to find the genes related to the degradation of organic matter in the genome.17 carbohydrate（including cellulose,starch,and other carbohydrate）degradation enzyme genes,12proteolytic enzyme genes,and 6 lipolytic enzyme genes were found,some of which encode thermostable enzymes.To some extent,these information explained the strong organic matters degradation ability of the strain,and also provided a reference for future theoretical research. |
