Metabolic activities of Lactobacillus spp. strains isolated from kefir.
A total of 21 strains of Lactobacillus species were isolated from Turkish kefir samples, in order to select the most suitable strains according to their metabolic activities including probiotic properties. As a result of the identification tests, 21 Lactobacillus isolates were identified as L. acidophilus (4%), L. helveticus (9%), L. brevis (9%), L. bulgaricus (14%), L. plantarum (14%), L. casei (19%) and L. lactis (28%). The amount of produced lactic acid, hydrogen peroxide, proteolytic activity, and acetaldehyde productions of Lactobacillus spp. were determined. Different amounts of lactic acid were produced by strains studies; however, lactic acid levels were 1.7-11.4 mg/mL. All strains produced hydrogen peroxide. L. bulgaricus Z14L strain showed no proteolytic activity, L. casei Z6L strain produced the maximum amount (0.16 mg/mL) of proteolytic activity. Acetaldehyde concentration produced in Lactobacillus strains ranged between 0.88-3.52 microg/mL.
Gazi University, Faculty of Science and Arts, Department of Biology, Teknikokullar, Ankara, Turkey. zehranur@gazi.edu.tr
Zehra Nur
ZN
Yüksekdag
Yavuz
Y
Beyath
Belma
B
Aslim
D000079:Acetaldehyde / Q000032:analysis; D043302:Cultured Milk Products / Q000382:microbiology*; D005516:Food Microbiology; D006861:Hydrogen Peroxide / Q000032:analysis; D019344:Lactic Acid / Q000096:biosynthesis*; D007778:Lactobacillus / Q000378:metabolism*; D014421:Turkey
D019344:Lactic Acid; D006861:Hydrogen Peroxide; D000079:Acetaldehyde