Studying bacterial community in fermented foods by using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE)

Abstract

Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) fingerprinting was recently introduced into food microbiology. PCR - DGGE were used to investigate bacterial communities developed in Hanoi and Tharủihoa nem chua. Total microbial DNAs were extracted directly from 10 nera chua samples. PCR of V3 I6S rDNAs were subjected to DGGE analysis. The resuite have showed that 10 nem chua samples have different bands involved to microbial species in nem chua. 53 bands were collected. Then, these bands were cut, purified, sequenced and compared to known sequence database in EMBL bank. The results indicated that there are mostly belong to lactic acid bacteria such as genus Lactobacillus, Lactococcus. Pediococcus, Leuconostoc, VagQcoccus, Enterococcus. Weissella, remains only two as Macrococcus and Psychrobacter found in Hanoi and Thanhhoa nem chua. The results also indicated Lactobacillus are mainly member in nem chua and they play especially important role Ú1 producing specfic aroma, bacteriocin to improve the quality and preservation of nem chua as well.