Development of a quantitative PCR assay for rapid detection of Lactobacillus plantarum and Lactobacillus fermentum in cocoa bean fermentation

作者：Schwendimann Livia; Kauf Peter; Fieseler Lars; Gantenbein Demarchi Corinne; Schwenninger Susanne Miescher^*

来源：Journal of Microbiological Methods, 2015, 115: 94-99.

DOI：10.1016/j.mimet.2015.05.022

• Lactobacillus plantarum
• Lactobacillus fermentum
• qPCR
• Cocoa bean fermentation

To monitor dominant species of lactic acid bacteria during cocoa bean fermentation, i.e. Lactobacillus plantarum and Lactobacillus fermentum, a fast and reliable culture-independent qPCR assay was developed. A modified DNA isolation procedure using a commercial kit followed by two species-specific qPCR assays resulted in 100% sensitivity for L. plantarum and L. fermentum. Kruskal-Wallis and post-hoc analyses of data obtained from experiments with cocoa beans that were artificially spiked with decimal concentrations of L. plantarum and L. fermentum strains allowed the calculation of a regression line suitable for the estimation of both species with a detection limit of 3 to 4 Log cells/g cocoa beans. This process was successfully tested for efficacy through the analyses of samples from laboratory-scale cocoa bean fermentations with both the qPCR assay and a culture-dependent method which resulted in comparable results.

• 出版日期2015-8