The influence of red pepper powder on the density of Weissella koreensis during kimchi fermentation

Abstract

Weissella koreensis is a psychrophilic bacterium that is the dominant species found in kimchi and exhibits anti-obesity effects via its production of ornithine. In this study, we mined the genome of W. koreensis KACC15510 to identify species-specific genes that can serve as new targets for the detection and quantification of W. koreensis in kimchi. A specific polymerase chain reaction (PCR) primer set for the membrane protein-encoding gene of W. koreensis KACC15510 was designed and investigated to quantify its sensitivity and specificity for detecting the bacterium in kimchi. The specificity of the primer set was evaluated using genomic DNA from eight isolates of W. koreensis, 11 different species of Weissella and 13 other reference lactic acid bacterium (LAB) strains. In addition, red pepper powder was observed to strongly influence the density of W. koreensis during kimchi fermentation.