Article Search
닫기

Microbiology and Biotechnology Letters

View PDF

Microbiol. Biotechnol. Lett. 2004; 32(3): 249-255

발효 온도에 따른 김치의 산도 변화와 Vancomycin 내성 젖산균의 분포

Changes in Acidity and Distributions of the Vancomycin-Resistant Lactic Acid Bacteria in the Kimchi Fermented at Different Temperatures

Abstract

Chinese cabbage ('Baechu') Kimchi was fermented at the three different temperatures right after it was prepared. Samples were taken everyday for measuring bacterial populations, pH, and titratable acidity through the whole periods of fermentation up to 50 days. pH values and developed acidity were significantly affected by the fermenting temperatures of 4, 10, and $20^{circ}C$, suggesting that different bacterial flora has been established by the temperatures exposed. The modified MRS agar containing vancomycin (300 $mu$g/mL) was used for isolating the vancomycin-resistant LAB strains and 127 isolates were finally obtained. Of the LAB isolates, 13 isolates were subjected to the identification experiments based on the biochemical characteristics and the molecular-typing approach, an ITS-PCR, whether they belong to the genus Leuconostoc or not. The data obtained from API 50 CHL kit resulted that six isolates were identified as the members of Leuconostoc and six as Lactobacillus brevis strains except for a single isolate YKI 30-0401, which was not able to be identified because its biochemical traits were not matched to the database of API 50 CHL kit. It was noted that some isolates were distinct in a couple of some biochemical characteristics compared with those of the reference Leuconostoc species. To overcome the limitations experienced in the commercial identification products above, an ITS-PCR experiment was also conducted for the isolates, resulting that eight isolates belong to Leu. mesenteroides ssp. mesenteroides or dextranicum with a single band of 564 bp, and four to L. brevis strains. The ITS-PCR profiles clearly differentiated the closely-related LAB isolates for which same results were obtained by the biochemical method. This molecular approach, however, failed to produce the amplicons for the YKI 20-1003, leaving the strain unidentified. Judging from the identification data obtained in the Kimchi fermented at $4^{circ}C$ or $10^{circ}C$, Leuconostoc spp. including Leu. mesenteroides/dextranicum were likely predominant species in the earlier stage and L. brevis occurred at the high level through the whole period. By contrast, L. brevis, as one of the major flora, possibly lead the fermentation from the beginning in the Kimchi fermented at $20^{circ}C$.}C$.

Keywords: Leuconostoc;Kimchi;identification;ITS-PCR method;vancomycin-resistant;

Starts of Metrics

Share this article on :

Most Searched Keywords ?

What is Most Searched Keywords?

  • It is most registrated keyword in articles at this journal during for 2 years.