Analysis Of Microbial Diversity In Fermented Grains Of Shanxi Mature Vinegar And And Effects Of Sorghum Tannin On Fungi Growth

Shanxi mature vinegar is one of the four famous vinegars in China widely loved by consumers with rich and mellow aroma and a variety of healthy efficacy.The objective of this experiment was to separate and identify yeasts and molds from the shanxi mature vinegar during different fermentation periods.PCR-DGGE method was used to analyze the bacteria population from shanxi mature vinegar during different fermentation periods.Finally,the effects of sorghum tannin on the growth of yeasts and molds identified from the shanxi mature vinegar were studied.This work can provide a theoretical basis for the selection of sorghum varieties with reasonable tannin content,and thus improve the utilization rate,yield and quality of shanxi mature vinegar.By using dilution plate coating method,39 strains of yeasts and 10 strains molds were isolated from the shanxi mature vinegar during different fermentation periods.39 strains of yeasts were classified as Saccharomyces cerevisiae,Pichia jadinii,Pichia kudriavzevii,Saccharomycopsis fibuligera,Pichia fermentans,Wickerhamomyces anomalus,Saccharomyces fibuligera and Pichia kudriavzevi by physiological and ITS sequence analysis.10 strains molds were classified as Lichtheimia corymbifera,Mucor circinelloides,Aspergillus japonicas and Aspergillus hancockii by physiological and ITS sequence analysis.DNA of bacteria were directly extracted from the Shanxi mature vinegar during different fermentation periods,and the PCR amplification of 16 S r DNA V3 region were taken in order to get the atlas by DGGE technology,the main bands in the DGGE atlas were recovered and sequenced.Sequence analysis showed that the dominant bacteria from shanxi mature vinegar during different fermentation periods were found to be Pediococcus lolii,Acetobacter okinawensis,Fructobacillus sp.,Pediococcus sp.,Lactobacillus alimentarius,Lactobacillus sakei and Acetobacter pasteurianus.The effects of volume fraction 80% and 30% ethanol elution tannin on the growth of yeasts and molds isolated from shanxi mature vinegar during different fermentation periods were studied.The growth of all the yeasts and molds were promoted in varying degrees when the concentration of tannin increased from 0 to 1.0%.The growth of most yeasts and all the molds were promoted when the concentration of tannin was 1.5%.And the growth of most yeasts and all the molds were inhibited with the concentration of tannin of 2.0%.Moreover,with the concentration of tannin increased continually,all the yeasts and molds were inhibited obviously and could not grow thoroughly when the concentration of tannin was 5.0%.