Goat whey fermentation by Kluyveromyces marxianus and Lactobacillus rhamnosus release tryptophan and tryptophan-lactokinin from a cryptic zone of alpha-lactalbumin

摘要

Angiotensin-I-Converting Enzyme (ACE) inhibitors peptides were produced from unsupplemen-ted acid goat whey fermented aerobically for 168 h by Kluyveromyces marxianus and Lactobacillus rhamnosus. This yeast-lactobacillus association is CRAS. Two novel lactokinins were identified: NYW and W with IC_(50) of 20 and 0.86 μm respectively. They both were resistant toward simulated gastrointestinal digestion. In addition, WLAHK was found in the hydrolysate. These three sequences belong to f(99-110) of α-la which seems to be a lactokinin cryptic zone. W was the major molecule released by the fermentation process. Considering that W is the precursor of serotonin, the hydrolysate produced could be of interest for the generation of functional health ingredient involved in regulation of affective disorders and hypertension.