The Morphology And PCR-DGGE Analysis Of Bacterial Community Diversity In The Fermentation Broth Of Natural Fermented Sauerkraut

Northeast sauerkraut is one of the featured foods made by the fermented and salted cabbage with strong local characteristics.In this research,the traditional cultured analysis technology,DGGE analysis technology and 454 high-throughput sequencing technology were used to analyze the dynamic changes on the microbial community of Northeast sauerkraut via natural fermentation and fermentation with Lactobacillus paracasei(HD1.7)process.The biodiversity of Northeast sauerkraut has been studied by the analysis technology based on cultured,DGGE analysis technology and 454 high-throughput sequencing technology.It turned out that all of bacteria structures were constantly changing.At the early days of natural fermentation,there were many of dominance such as Aerobic mesophilic?Enterobacteria?Lactic acid bacteria?yeast and molds?Enterococcus.After three days,Lactic acid bacteria has become the dominant bacteria.Aerobic mesophilic were going on steady growth,but others were starting declined.At the early days of fermentation with HD 1.7,there were many of dominance such as Lactic acid bacteria?Aerobic mesophilic?yeast?Enterobacteria?Enterococcus.At the first days,Lactic acid bacteria has becomed the dominant bacteria.Aerobic mesophilic and yeast was not going on steady growth until becoming dominant bacteria,but others were starting to decreasing.18 kinds of bacteria were isolated during natural fermentation process such as Lactobacillus plantarum,Lactobacillus brevis,Enterobacter sp.,Klebsiella pneumoniae,Bacillus sp.,Staphylococcus sp.,yeast.17 kinds of bacteria were isolated during fermentation with HD 1.7 process,the kinds were same to the natural fermentation except,Lactobacillus paracasei(HD1.7).During both of the two fermentation process,neither pathogenic strains Staphylococcus aureus nor Bacillus cereus were found.DGGE technique was used to find the Bacterial diversity,and then 22 bands were isolated from the natural fermented liquid and 17 bands from fermentation with HD 1.7 liquid.The results were not entirely consistent with the analysis above-mentioned.But Lactic acid bacteria is the mainful bacteria of dominance from the first day.One hundred kinds of bacteria in the natural fermented liquid were confirmed by 454 high-throughput sequencing analysis,in which not only covered all the strains detected by the two techniques above.Forty strains were also additionally found with lower dominance.It was turned that Lactic acid bacteria was become the bacteria of dominance at the three days by the resukts of Rarefaction curves,Shannon-we iener curves,Rank-Abundance curves,VENN picture,Mcrobial community barplotand Heatmappicture,First of all,Lactococcus was become the the most important bacteria of dominance,and then lactobacillus take the place of Lactococcus,finally lactobacillus become dominant strain and account for 87.37%of the total lactobacilli bacteria.