Thesis (BS Food Technology) -- University of the Philippines Mindanao, 2010

Caprine milk form a local supplier was fermented with enterococcus faecium DMF78, a published local isolate, for forty-eight hours. The angiotensin I-converting enzyme (ACE) inhibitory activity of the water soluble fration of the milk hydrolysate was monitored every eight hours by using HHL (hippuryl-L-histidyl-Lleucine) as substrate for ACE. The liberated HA (hippuric acid) was quantified using RP-HPLC. Lactobacillus helveticus, a know bacterium reported to have released inhibitory peptides from bovine milk through fermentation, was also used as a starter for caprine milk and analyzed for comparison. It was found out that the activities from the two bacteria were not significantly different from each other. Furthermore, the ACE inhibitory activities per sampling hour were also not significantly different. Peptide content, total plate count (TPC) and pH showed no significant correlation with percent inhibition suggesting other unmeasured factors to contribute to the inhibitory activity. The IC50 determined from the sour milk fermented with E. faecium DMF78 was 88.24mg/mL. there are many literatures that studied on ACE inhibitory activity of fermented milk however these focused on the activities of the purified peptides from the milk hydrolysate and not on the activities of the crude milk hydrolysate was done in this study. A preliminary assessment of the virulence of E. faecium DMF78 performed using hemolysin production assay and an antimicrobial susceptibility assay using 1% concentration of ampicillin, amoxicillin and streptomycin. It was found out that the strain was resistant to all these antibiotics and this concentration but not very alarming since the strain was negative to hemolysin production which was the more important virulence trait.