Antioxidant and modulatory properties of kernel flour extracts of three Nigerian local mango varieties on enzymes relevant to metabolic syndrome

Abstract

Aim: Recent studies have shown that flour of mango kernel is a rich natural source of biologically active phytochemicals with important health benefits, such as phenolic compounds. Hence, this study evaluated antioxidant and modulatory properties of methanol extracts of kernel flours of three Nigerian local mango varieties (Sherri, Ogbomoso and Elemi) on some enzymes relevant to the development of metabolic syndrome (MS). Methods: Enzymes [pancreatic lipase (PL), α-amylase, α-glucosidase, angiotensin I-converting enzyme (ACE) and xanthine oxidase (XO)] inhibitory assays, antioxidant activities and antioxidant phytochemicals contents of extracts were carried out using spectrophotometer. Results: All the three mango varieties strongly inhibited PL, α-amylase, α-glucosidase, ACE and XO. Generally, Elemi had the strongest inhibitory effect on the enzymes, followed by Sherri and Ogbomoso. It also had the highest total phenols, total flavonoids, tannins and total saponins contents, and displayed the strongest ABTS*+ and DPPH* scavenging activities and reducing power, compared with Sherri and Ogbomoso. Conclusions: By inhibiting PL, α-amylase, α-glucosidase, ACE and XO, kernel flour extracts of the three Nigerian local mango varieties may be beneficial for retarding the production of fatty acids, glucose, angiotensin II and uric acid, representing an important approach for managing obesity, T2D, hypertension and hyperuricemia, respectively. The mango kernel flours, especially Elemi, may therefore be harnessed to develop low-cost nutraceuticals for managing metabolic syndrome.