The Inhibitory Effects of New Zealand Pine Bark (Enzogenol(®)) on α-Amylase, α-Glucosidase, and Dipeptidyl Peptidase-4 (DPP-4) Enzymes

The New Zealand pine bark extract (Enzogenol(®)) has previously been shown to elicit acute hypoglycaemic effects in humans. The present study investigated the underlying mechanisms of Enzogenol(®) in reducing postprandial glucose in humans. The potential inhibitory action of Enzogenol(®) against digestive enzymes: α-amylase and α-glucosidase, and dipeptidyl peptidase-4 (DPP-4) enzyme was determined. Enzogenol(®) demonstrated the ability to inhibit all three enzymes: α-amylase enzyme activity (IC(50) 3.98 ± 0.11 mg/mL), α-glucosidase enzyme activity (IC(50) 13.02 ± 0.28 μg/mL), and DPP-4 enzyme activity (IC(50) 2.51 ± 0.04 mg/mL). The present findings indicate the potential for Enzogenol(®) to improve postprandial glycaemia by delaying carbohydrate digestion via the inhibition of digestive enzymes (α-amylase and α-glucosidase), and enhancing the incretin effect via inhibiting the dipeptidyl-peptidase-4 enzyme. The inhibitory actions of Enzogenol(®) on enzymes should therefore be further validated in humans for its potential use in type 2 diabetes mellitus prevention and management.