Application Of DGGE Technology In The Analysis Of The Bacterial Flora Of IC Reactor In Citric Acid Wastewater And Study On High Value Utilization Of Slag

The reactor community composition and the dynamic changes are related to the reactor efficiency closely in the citric acid wastewater IC reactor treatment process.So probe the reactor community characteristics of sludge flora,analyze the relationship between the composition of flora and reactor efficiency,can provide a theoretical basis for improving the efficiency of the reactor.In this paper,applying PCR-DGGE technique to analyze the dynamic changes of IC reactor sludge microorganisms under continuous operating and analyze the relationship between the efficiency of the reactor,lay the foundation for further research to improve the reaction efficiency.Citric acid produces waste mainly from corn,the sugar residue was filtered after saccharification,its nutrients is single and mainly composed of protein and fiber.Improved composition and structure of residue and the nutritional value by microbial fermentation,so the slag can obtain a high-value use.This paper uses a single strain fermentation and mixed strains fermentation method to fermentate residue,aimed at improving the nutritional value of the slag.The main work and results of this study are as follows:(1)In order to obtain a more comprehensive and accurate analysis results for the IC reactor sludge flora rich and structure complex,this study optimized methods and established it targeted for PCR-DGGE analysis.The study compared three DNA extraction methods,three factors were optimized in the three levels that affect DGGE electrophoresis.By the comparison of method and the optimization of conditions,establishing a PCR-DGGE analysis for IC reactor sludge samples,and lay the foundation for a comprehensive analysis of the sludge flora characteristics.(2)Utilizating established methods of DNA extraction and PCR-DGGE electrophoresis conditions to analyze the dynamic composition of microbial community which is interval samples in continuous operation and in the different position of the IC reactor 16 sludge.PCA analysis and cluster analysis are used synthetically and obtained: in the continuous operation IC reactor,the type and quantity of sludge bacteria does not change with running time;the sludge of reactor,flora species does not vary with position change,while the content will change between different species,of which the most significant change are Bacteroides bacteria protein doors and gates.Flora are dynamic steady state in the reactor,and the efficiency of wastewater treatment and biogas production also remains dynamic stability in the reactor.(3)Select a Bacillus subtilis and Saccharomyces cerevisiae,uses a single strain fermentation and mixed strains fermentation method respectively to fermentate citric and produce residue.Optimize fermentation conditions of single fermentation and mixed fermentation respectively,due to the characteristics of Growth conditions is large for different species differences,and obtain the optimum fermentation conditions.By comparison of the two single bacteria fermentation product,found that the protein content and flavor of the products from Saccharomyces cerevisiae fermentate residue are higher than content of Bacillus subtilis.Comparison of single and mixed fermentation mixed fermentation residue was found to enhance the digestibility better and more easily digested and absorbed.