Screening for potential novel probiotic Lactobacillus strains based on high dipeptidyl peptidase IV and α-glucosidase inhibitory activity

• Published in: Journal of functional foods Vol. 20; pp. 486 - 495
• Main Authors: Zeng, Zhu, Luo, Junyi, Zuo, Fanglei, Zhang, Ying, Ma, Huiqin, Chen, Shangwu
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2016; Elsevier
• Subjects: Diabetes; Dipeptidyl peptidase IV; DPP-IV inhibition; Lactobacillus; Probiotic; α-glucosidase inhibition; DPP-IV inhibition; α-glucosidase inhibition; Probiotic; Dipeptidyl peptidase IV; Diabetes; Lactobacillus
• ISSN: 1756-4646; 2214-9414
• DOI: 10.1016/j.jff.2015.11.030

•Lactobacillus strains displayed DPP-IV inhibitory activity in vitro.•DPP-IV inhibition was concentration-dependent and stable to temperature and pH.•Trypsin treatment significantly enhanced DPP-IV inhibitory property.•Some strains showed both DPP-IV and α-glucosidase inhibitory property in vitro. Lactobacillus strains were screened for inhibition of dipeptidyl peptidase IV (DPP-IV) and α-glucosidase. Cell-free excretory supernatants (CFS) and cell-free extracts (CFE) of 21 strains were prepared, and most of them showed DPP-IV inhibition in a concentration-dependent manner, which started at the exponential phase and peaked at the stationary phase of the Lactobacillus. The CFS bioactivity was heat-resistant, stable to acid–alkali and glucosidase treatment. Trypsin treatment specifically elevated CFS's DPP-IV inhibition. Lactobacillus plantarum strains CFS displayed different protein patterns and trypsin sensitive bands on SDS-PAGE, demonstrating specific peptide-cleavage contributes to higher inhibition. Seven strains with highest DPP-IV inhibition also displayed α-glucosidase inhibitory activity, of which, three strains of L. plantarum and one of Lactobacillus brevis showed tolerance to simulated gastrointestinal tract conditions and high HT-29 cell adhesion. This initial report of lactobacilli secreting strong DPP-IV and α-glucosidase inhibition components will be beneficial for selection and application of anti-diabetic probiotics.