Inclusion of Allium sativum in Yogurt and its Effects on Inhibition of Diabetes and Hypertension-associated by Enzymes in vitro

Abstract

The effects of Allium sativum on yogurt formation and subsequent storage (4°C, up to 28 days) on proteolysis, microbial activity, and inhibition of α-amylase, α-glucosidase and angiotensin-I converting enzymes were investigated in vitro. Allium sativum yogurt showed higher rates of pH reduction and increment of titrable acid than control during the incubation at 41°C. Highest proteolysis was observed on day 7 in Allium sativum yogurt (62.7±0.80 mgmL-1), which was 2-flod higher than the control (31.0±0.96 mgmL-1). Bacterial counts in Allium sativum yogurt were higher for Lactobacillus spp. but lower for Streptoccus thermophilus (p<0.05) compared to those in the control throughout refrigerated storage. Highest inhibitory activities for α-amylase were recorded on day 14 of storage for Allium sativum and the control yogurt while highest inhibitory activities for α-glucosidase were recorded on day 7 of storage for Allium sativum and the control yogurt respectively. The highest angiotensin-I converting enzymes activity was observed on day 7 of the refrigerated storage in Allium sativum yogurt, and being more potent than the control. Allium sativum enhanced the fermentation of yogurt in favor of the population of Lactobacillus sp, stimulated proteolysis of milk proteins, and increased the in vitro inhibition of key enzymes associated with diabetes and hypertension.