0000000000828717
AUTHOR
Patrick F. Fox
Characterization of sourdough lactic acid bacteria based on genotypic and cell-wall protein analyses
Abstract Aims: To evaluate the effectiveness of two independent methods in differentiating a large population of lactic acid bacteria (LAB) isolated from wheat flours and sourdoughs and to correlate eventual differences/similarities among strains with their geographical origin and/or process parameters. Methods and Results: One hundred fifty strains belonging to Lactobacillus spp. and Weissella spp., plus eight type strains, one for each species, and two unidentified isolates, were characterized by randomly amplified polymorphic DNA (RAPD) and SDS-PAGE of cell-wall proteins. The RAPD analysis separated the eight type strains but did not always assign all the strains of a species to the same…
Genotypic characterization of lactic acid bacteria isolated from traditional Pecorino Siciliano cheese
A total of 468 lactic acid bacteria (LAB) isolates from the interior of six traditional Pecorino Siciliano cheeses during ripening (1, 30 and 90 days) were characterized genotypically in order to assess the biodiversity within this wild microbial population. Two DNA-based technique, PCR and PFGE were used for genetic typing of isolates. Of the 468 isolates, species-specific PCR analysis showed that 79, 58, 2, 9 and 4 isolates reacted with primers for Lactobacillus paracasei, Lb. plantarum, Lb. pentosus, Lb. rhamnosus and Lb. curvatus, respectively and no isolates reacted with the Lb. casei primers. Genus-specific PCR analysis showed that 59 isolates reacted positively with the lactococcal p…