Application of a novel polyphasic approach to study the lactobacilli composition of sourdoughs from the Abruzzo region (central Italy)

Aims: To characterize the lactobacilli community of 20 sourdoughs using a novel polyphasic approach. Methods and Results: A polyphasic approach, consisting of a two-step multiplex polymerase chain reaction (PCR) system, 16S rRNA gene sequence analysis and physiological features, was applied to identify 127 isolates, representing about 37% of the presumptive lactobacilli collected from sourdough samples. Multiplex PCR successfully identified 111 isolates, while 16S rRNA gene sequencing was applied for the other 16 isolates, two of which could not be associated with any previously described lactic acid bacteria (LAB) species. Strain diversity was evaluated by phenotypic and random amplified polymorphic DNA-PCR analysis. Molecular detection of Lactobacillus group species was also performed on total DNA extracted from the doughs.Multiplex Abruzzo region sourdough lactobacilli biodiversity, reflected in both Lactobacillus species composition and strain polymorphism, is similar to that of other Italian regions and is a source of novel LAB species. Conclusions: Significance and Impact of Study: Within culture-independent methods, multiplex PCR is a rapid tool to study the lactobacilli population of sourdoughs.