Probiotic Lactobacillus casei ADA03 as a starter culture released angsotensin converting enzyme inhibitors from bovine milk

摘要

This study was undertaken to determine whether probiotics can release angiotensin converting enzyme (ACE) inhibitory peptides from bovine milk. Four probiotic strains including Lactobacillus casei ADA03, L. casei ADA05, L. acidophilus MR100, and L. bulgaricus MR110 were used to ferment milk at 37°C for 18, 24 and 48 h. Lactobacillus case/ADA03 was shown to release peptides having the strongest ACE inhibitory activity with IC_(50) values of 2936 and 1118 mu g/ml in samples fermented for 18 and 24 h,respectively. Other probiotics showed weaker ACE inhibitory activities. Ultrafiltration with molecular weight cut-off of 2000 Da was employed to fractionate the supernatant of each fermented milk sample. Permeate obtained after ultrafiltration showed stronger ACE inhibitory activity than corresponding supernatant in most samples examined. The ACE inhibitory activity was found to be the highest in the permeate from milk fermented with L. casei ADA03 for 24 h with IC_(50) values of 252 mu g peptide/ml.