Lactobacillus plantarum strains isolated from traditional Greek cheese. Taxonomic characterization and screening for enzyme activities

Summary - A total of 16 mesophilic homofermentative lactobacilli were isolated from Xynotyri, a traditional Greek cheese. Identification of strains was performed by phenotypic methods and by SDS-polyacrylamide gel electrophoresis of whole-cell proteins; strains were found to belong to the Lactobacillus plantarum species. Peptidase and esterase activities were detected spectrophotometrically and electrophoretically in the cell-free extracts of the strains, using synthetic substrates. The proteolytic activity of whole cells in milk, as weil as the proteolytic activity of cell-free extracts on whole bovine casein were examined. Slqnitlcant differences within the species were observed, allowing the selection of technologically interesting strains.