In Vitro Combined Effect of Annona Senegalensis and Piliostigma Thonningii Leaf Extracts on Alpha Amylase Activity

Abstract

Background: Diabetes mellitus (DM), a group of metabolic disorders characterised by hyperglycaemia, has been attributed to increased activity of α-amylase, one of the key enzymes in carbohydrate metabolism. Alpha amylase inhibition can potentially control postprandial hyperglycaemia, hence significant in the management of diabetes mellitus, especially type 2. Acarbose, the proven α-amylase inhibitor, has been associated with several side effects. Plants used in traditional medicine represent a valuable source in the search for an alternative. The study aimed at determining the combined effect of Piliostigma thonningii and Annona senegalensis leaf extracts on alpha amylase activity. Methodology: Mortar and pestle were used to crush the leaves into powder. The fine powder was dispensed in distilled water. Percolation was used to filter the crude extract, evaporated in a water bath at 65 0C to concentrate the extract then reconstituted. Spectrophotometric assay method was used for alpha amylase activity at 540 nm. Results: The results of the study showed that A. senegalensis inhibited α-amylase by 27%, 32% and 34% at 15, 30 and 45 minutes respectively. P. thonningii exhibited inhibitory effects on α-amylase by 25%, 27% and 37% at 15, 30 and 45 minutes respectively. The combined inhibitory effects of A. senegalensis and P. thonningii on α-amylase were 28%, 37% and 62% at 15, 30 and 45 minutes respectively which are significantly different (p <0.05) from that of the positive control, acarbose (71% at 45 minutes) Conclusion: This study revealed the increased strength to inhibit alpha amylase enzyme by a combination of A. senegalensis and P. thonningii and a proportional increase in the inhibitory effect with increase in incubation time than their individual potential to inhibit alpha amylase.