Research And Development On Compound Microbial Agents For Effective Degradation Of Kitchen Waste

Food wastes are kitchen leftover and hogwash generated in kitchen and eatery, mainly containing organics such as starch, protein, fat and cellulose, if these aren’t treated in time, they will pollute the environment. However, the composition could be degraded by microorganism agent and it realize the recycling of resources. It is significant to treat food waste timely and harmlessly and realize the recycling of resources.This study focused on developing an effective microbial agent for degradation of food wastes. Several effective strains were isolated from kitchen garbage and some microbial agent. Using Response Surface Methodology (RSM) to optimize the fermentation conditions of mixed culture fermentation, to optimize the kitchen waste disposal process. The comparation of applicaton effects was taken between the self-made compound agent and commercial agent. The experimental research has been expatiated as follows:1)104strains of microorganisms were isolated from kitchen garbage and some environmental samples, including85strains of bacteria and19strains of fungi. They were identified by16SrRNA or rDNA-ITS sequence comparing.13strains were selected as the major component of microbial agents after further screening, optimization and combination. These strains include:5strains which were common in kitchen waste degrading;3high-efficient degrading bacteria; and5strains which were first applied in kitchen waste degrading (Brevibacterium epidermidis, Paenibacillus polymyxa, Aspergillus versicolor, Penicillium digitatum and Aspergillus japonicus). These provide a new reference for people to select biodegradable kitchen waste microbial strains.2) By using the RSM method to optimize the fermentation conditions, the optimal fermentation conditions were founded:temperature35℃, intermittent oscillation, cultivating108h. The optimal weight percentage and solid materials is, broken shell:shavings:fish bone meal:bran:bacteria=2:1:1:1:1. This is most suitable for storage and transportation. The results of RSM indicated that the reduction of food wastes was up to40%when the temperature is45℃,6%microbial agent added,30%sawdust added. The degradation of the test results for kitchen waste provides data for the optimization of process control conditions.3) Compared with other three commercially available microbial agents in decrement, deodorization and rotten effect experiment, self-made microbial agents show more effective on kitchen waste reduction and deodorization than those of three commercial agents, but rotten effect is worth further research and optimization. Comprehensively, this self-made microbial agents has more obvious effect on the degradation of kitchen waste, and is expected to be developed and applied.