Screening And Identification Of Decomposition Bacteria In Kitchen Waste And Research On Microbial Agents

Kitchen waste is a type of wet waste with much water and high organic matter,and it is perishable and can breed flies.How to deal with it efficiently,resourcefully and harmlessly needs urgent research.Related research shows that biological treatment methods,especially the inoculation of microbial inoculants,are expected to become a sustainable way to garbage disposal.In order to develop high-efficiency microbial inoculants for the biological treatment of kitchen waste,a large number of thermophilic strains were obtained,and high-efficiency strains are retained through the comparison of enzyme-producing ability.The best combination of bacteria was used to prepare a high-efficiency composite microbial inoculum.Morever,the activity of the inoculum was tested and the degradation of food waste was evaluated.The main results are as follows:59 strains of well-grown thermophilic bacteria(50?)were isolated from three kinds of biological materials through traditional microbiological methods,including 44 strains of bacteria and 15 strains of actinomycetes.For the 59 strains metioned above and 40 strains preserved in the laboratory,the transparent circle method was used to determine the enzyme production ability of them on starch,protein,fat,and cellulose.Therefore,71 dominant bacteria were obtained,including 57 bacteria,4 molds and 10 yeasts.The unidentified strains among the 71 dominant strains were identified preliminarily by16S r DNA PCR amplification-sequencing.The results showed that 28 strains of Bacillus,6strains of Geobacillus,1 strain of Paenibacillus,6 strains of Cupriavidus,and 1 strain of Pseudomonas and 1 strain of Acinetobacter.Antimicrobial susceptibility tests were conducted on some strains by the paper diffusion method.The results showed that these strains were all sensitive to the tested antibiotics and were easier to control with known antibiotics.Orthogonal experiments were used to determine the combination of high-efficiency strains that degraded starch,protein,oil and cellulose in food waste perspectively.Among them,the optimal combination of starch degraded 91.9%of starch within 48 h.The optimal combination of protein degraded 76.6%of protein within 48 h.The optimal combination of oil degraded69.0%of oil within 48 h.The optimal combination of cellulose degraded 54.9%of cellulose in72 h.The efficient combination of strains mentioned above were combined to obtain a compound microbial inoculant for efficient degradation of kitchen waste by using coconut bran as a carrier.And there are 16 strains of Bacillus,2 strains of Bacillus,3 strains of Geobacillus,4 strains of Corynebacterium,1 strain of Acinetobacter,4 strains of mold,and 3 strains of yeast in the compound inoculant.The avtivity of the inoculant was tested,and the results showed that the order of mesophilic bacteria(10¹⁰ CFU/g),thermophilic bacteria(10¹⁰ CFU/g)and fungi(10⁷ CFU/g)in the composite inoculant didn't change obviously in the storage period.The activity remained good.The prepared composite inoculants and kitchen waste are put into a small household kitchen waste treatment machine at a ratio of 2:1.And kitchen waste was put into the machine every day.The reduction of kitchen waste is 95.1%,which is higher than that grpup without adding compound bacteria(69.2%),and the results indicate that the decomposition of kitchen waste under the action of inoculants is effective,which demonstrates the high efficiency of the prepared inoculant.