Harnessing the potency of home-garden herbs: Natural beverages for managing postprandial hyperglycaemia

Abstract

Postprandial hyperglycaemia and high oxidative stress increase the risk of developing non- communicable diseases and complications. Polyphenolic compounds present in herbal leaves, can control the postprandial blood glucose while increasing the antioxidant capacity. In this study the effects of selected herbal beverages [Coccinia grandis (KT), Murraya koenigii (AT), Hemidesmus indicus (IT), and Scoparia dulcis (WT)] on postprandial blood glucose (PPBG), total phenolic content (TPC), in-vitro antioxidant capacity (AOC), and in-vivo antioxidant effect were assessed. To assess the effects on PPBG, blood glucose levels were analyzed in healthy human volunteers (n=15) at every 30 minutes over 2 hours, after consumption of above beverages (2 g leaf powder brewed in 125 mL for 2 minutes) or hot water (control-CT) or green tea (standard-ST) with a standard meal, on separate days. TPC and in-vitro AOC of two beverages (KT and WT) with the highest PPBG control were analyzed by Folin-Ciocalteu method [expressed in Gallic acid Eq/g (GAE/g)] and ABTS free radical scavenging assay [expressed in TroloxEq/g] respectively. In-vivo AOC of healthy individuals (n=13) was assessed in serum immediately before and one hour after consumption of the beverages. Compared to CT, significantly low PPBG levels were observed in KT, WT, and ST (p<0.05). The highest TPC was in ST (107.5±5.7GAE/g) followed by WT (18.7±0.8GAE/g). In-vitro AOC was significantly high (p<0.05) in ST (7.3±0.3TroloxEq/g) compared to WT (0.6±0.04TroloxEq/g) and KT (0.2±0.03TroloxEq/g). In-vivo AOC increment after one hour from consumption of KT (0.013 ±0.119TroloxEq/g) was comparable to ST (0.005±0.063TroloxEq/g), while WT (-0.066 ±0.071TroloxEq/g) elicited no AOC increment after one hour from consumption. Hence, it can be concluded that WT and KT possess considerable PPBG controlling effects.
Keywords: Herbal tea beverages; Postprandial blood glucose; Antioxidant capacity