Enterococcus faecalis milk fermentates display antioxidant properties and inhibitory activity towards key enzymes linked to hypertension and hyperglycaemia

Abstract

In this study, Enterococcus faecalis milk fermentates were assayed for total phenolic content, related antioxidant activity and the inhibition of key enzymes linked to hypertension and hyperglycaemia. Of the 25 isolates, milk fermented with E. faecalis DPC5154 had the highest level of total phenolic compounds (739.06 µg GAE/ml) and demonstrated the highest level of Trolox Equivalent Antioxidant Activity (TEAA) based on DPPH radical scavenging activity and ferric reducing antioxidant power (271.27 TEAA (µM) and 272.75 TEAA (µM), respectively). Inhibition of Angiotensin Converting Enzyme (ACE) and α-glucosidase is considered a useful therapeutic approach in the management of hypertension and hyperglycaemia, respectively. Milk fermented with DPC5154 completely inhibited ACE and displayed the highest level of α-glucosidase inhibitory activity (33.41%). These studies provide in vitro evidence for the beneficial use of DPC5154 and other E. faecalis isolates for the generation of bioactive milk products with antioxidant, antihypertensive and anti-hyperglycaemic activity.

Keywords

• Enterococcus faecalis
• Milk fermentation
• Bioactive milk products
• Antioxidants
• ACE inhibition
• α-Glucosidase inhibition