title: Rapid enzymatic method for biotyping and control of lactic acid bacteria used in the production of yogurt and some cheeses.
abstract: Determination of enzymatic patterns of 30 strains of Streptococcus thermophilus and 18 strains of Lactobacillus delbrueckii subsp. bulgaricus with a rapid APIZYM method was carried out. Alkaline and acid phosphatase, naphthol-AS-BI-phosphohydrolase, 10 esterases, 20 glycosidases, 61 peptidases and 2 proteases (trypsin and chymotrypsin) were included. The strains investigated were isolated from yogurt and from different starters used for different Italian cheeses. For S. thermophilus, all strains were positive for 3 glycosidases, 4 monopeptidases, 9 dipeptidases, 1 tripeptidase and all were negative for 2 esterases; 9 glycosidases; 8 peptidases and trypsin. For L. delbrueckii subsp. bulgaricus it was observed that all strains were positive for 2 esterases; 2 glycosidases; 11 monopeptidases, 9 dipeptidases, 2 tripeptidases and 1 tetrapeptidase and all were negative for alkaline-phosphatase; 3 esterases, 7 glycosidases, 5 monopeptidases, 2 dipeptidases. The defined enzymatic pattern of starter cultures can be used for predicting their suitability for dairy fermentations and for monitoring their stability as well as for typing.
authors.affiliation: Centro Sperimentale del Latte, Zelo Buon Persico (MI), Italy.
authors.forename: B
authors.initials: B
authors.lastname: Bianchi-Salvadori
authors.forename: P
authors.initials: P
authors.lastname: Camaschella
authors.forename: S
authors.initials: S
authors.lastname: Cislaghi
mesh_terms: D015373:Bacterial Typing Techniques; D002611:Cheese / Q000382:microbiology*; D004950:Esterases / Q000378:metabolism*; D005524:Food Technology / Q000379:methods*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D007778:Lactobacillus / Q000145:classification / Q000201:enzymology*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D013291:Streptococcus / Q000145:classification / Q000201:enzymology*; D013997:Time Factors; D015014:Yogurt / Q000382:microbiology*
chemical_list: D004950:Esterases; D010744:Phosphoric Monoester Hydrolases; D006026:Glycoside Hydrolases