Monitoring the bacterial community during fermentation of sunki, an unsalted, fermented vegetable traditional to the Kiso area of Japan
Department of Microbiology, University of Stellenbosch, Stellenbosch 7600, South Africa; NODAI Culture Collection Center, Tokyo University of Agriculture, Tokyo, Japan; Department of Microbiology, University of Stellenbosch, Stellenbosch, South Africa
Endo, A., Department of Microbiology, University of Stellenbosch, Stellenbosch 7600, South Africa, NODAI Culture Collection Center, Tokyo University of Agriculture, Tokyo, Japan, Department of Microbiology, University of Stellenbosch, Stellenbosch, South Africa; Mizuno, H., NODAI Culture Collection Center, Tokyo University of Agriculture, Tokyo, Japan; Okada, S., NODAI Culture Collection Center, Tokyo University of Agriculture, Tokyo, Japan
Aims: To investigate the microbial community in sunki, an indigenous, unsalted, fermented vegetable, made from the leaves of red beet. Methods and Results: Fermenting samples were collected at 1- to 2-day intervals from four houses and investigated by culture-dependent and culture-independent techniques. PCR-Denaturing-Gradient-Gel-Electrophoresis profiles indicated that the bacterial community was stable and Lactobacillus delbrueckii, Lact. fermentum and Lact. plantarum were dominant during the fermentation. This result agreed well with that obtained by the culturing technique. Moulds, yeasts or bacteria other than lactic acid bacteria (LAB) were not detected. Conclusions: The bacterial community was stable throughout the fermentation, and Lact. delbrueckii, Lact. fermentum and Lact. plantarum were dominant. The acidic pH and lactic acid produced by LAB probably preserve the sunki from spoilage. Significance and Impact of the Study: This is the first report on the use of both culture-dependent and culture-independent techniques to study the bacterial community in sunki. A combination of culture-dependent and culture-independent techniques is necessary for the analysis of complex microbial communities. © 2008 The Authors.
Agricultural products; Bacteria; Cell culture; Fermentation; bacterium; electrokinesis; fermentation; microbial community; monitoring; polymerase chain reaction; vegetable; article; bacterium identification; denaturing gradient gel electrophoresis; fermentation; food spoilage; Japan; lactic acid bacterium; Lactobacillus delbrueckii; Lactobacillus fermentum; Lactobacillus plantarum; microbial community; mould; nonhuman; pH; polymerase chain reaction; vegetable; yeast; Colony Count, Microbial; Fermentation; Food Microbiology; Hydrogen-Ion Concentration; Japan; Lactobacillus; Vegetables; Asia; Chubu; Eurasia; Far East; Honshu; Japan; Japanese Alps; Kiso Mountains; Nagano; Bacteria (microorganisms); Beta vulgaris subsp. vulgaris; Lactobacillus delbrueckii