title: Inhibition of key enzymes linked to type 2 diabetes and sodium nitroprusside induced lipid peroxidation in rats' pancreas by phenolic extracts of avocado pear leaves and fruit.
abstract: Persea americana fruit and leaves had been known in folk medicine for their anti-diabetic prowess. Therefore, this study sought to investigate the inhibitory effect of phenolic extract from avocado pear (Persea americana) leaves and fruits on some key enzymes linked to type 2 diabetes (α-amylase and α-glucosidase); and sodium nitroprusside (SNP) induced lipid peroxidation in rats' pancreas in vitro. The phenolic extracts of Persea americana fruit and leaves were extracted using methanol and 1M HCl (1:1 v/v). Thereafter, their inhibitory effects on sodium nitroprusside induced lipid peroxidation and key enzymes linked to type 2 diabetes (α-amylase and α-glucosidase) were determined in vitro. The result revealed that the leaves had fruit of avocado pear inhibit both α-amylase and α-glucosidase activities in a dose dependent manner. However, the Peel had the highest α-amylase inhibitory activity while the leaf had the highest α-glucosidase inhibitory activity as revealed by their IC50 value. Furthermore, incubation of the rat pancreas in the presence of 5 mM SNP caused an increase in the malondialdehyde (MDA) content in the tissue, however, introduction of the phenolic extracts inhibited MDA produced in a dose dependent manner. The additive and/or synergistic action of major phenolic compounds such as syringic acid, eugenol, vnillic acid, isoeugenol, guaiacol, kaemferol, catechin, ρ-hydroxybenzoic acid, ferulic acid, apigenin, naringenin, epigallocatechin, epicatechin, lupeol and epigallocatechin-3-O-gallate in avocado pear using gas chromatography (GC) could have contributed to the observed medicinal properties of the plant. Therefore, inhibition of some key enzymes linked to type 2 diabetes and prevention of oxidative stress in the pancreas could be some of the possible mechanism by which they exert their anti-diabetic properties.
authors.affiliation: Functional Foods and Nutraceuticals Unit, Department of Biochemistry, Federal University of Technology, Akure, Nigeria, P.M.B. 704, Akure, 340001, Nigeria;
authors.forename: Ganiyu
authors.initials: G
authors.lastname: Oboh
authors.affiliation: Department of Biochemistry, Ladoke Akintola University of Technology, Oyo State, Nigeria, P.M.B 4000, Nigeria;
authors.forename: Adelusi Temitope
authors.initials: AT
authors.lastname: Isaac
authors.affiliation: Functional Foods and Nutraceuticals Unit, Department of Biochemistry, Federal University of Technology, Akure, Nigeria, P.M.B. 704, Akure, 340001, Nigeria; ; Department of Biochemistry, Afe Babalola University, Ado-Ekiti, Nigeria, P.M.B. 5454, Nigeria.
authors.forename: Ayodele Jacobson
authors.initials: AJ
authors.lastname: Akinyemi
authors.affiliation: Department of Biochemistry, Ladoke Akintola University of Technology, Oyo State, Nigeria, P.M.B 4000, Nigeria;
authors.forename: Richard Akinlolu
authors.initials: RA
authors.lastname: Ajani
keywords: Persea americana; Type 2 diabetes; lipid peroxidation; α-amylase; α-glucosidase