In vitro Evaluation of Antiglycation, Antioxidation, and α-Glucosidase Inhibitory Activities of Ethanol Extracts of Terminalia Bellirica and Terminalia Chebula Fruits

Accumulation of advanced glycation end-products (AGEs) due to hyperglycemia and oxidative stress contributes to diabetic complications. Terminalia bellirica and Terminalia chebula are traditional medicinal fruits rich in bioactive phytochemicals with various pharmacological effects. This study assesses their hydroethanolic extracts (TBE and TCE) for phytochemical content, antiglycation, antioxidation, and α-glucosidase inhibitory activities, highlighting their potential for diabetes management. Total phenolics and tannins were measured by the Folin-Ciocalteu method, and flavonoids by aluminum chloride assay. Antiglycation activities were assessed with a bovine serum albumin/fructose model. Superoxide (SO) anion radical inhibition was measured through a riboflavin-light-nitroblue tetrazolium assay, while metal chelation activity was determined using an iron-ferrozine assay. Alpha-glucosidase inhibition was assessed with p-nitrophenyl-α-D-glucopyranoside (p-NPG) substrate. TBE showed significantly higher phenolics (516.44 ± 2.08 mg GAE/g) and tannins (591.0 ± 8.43 mg TAE/g) than TCE, indicating its superior phytochemical content (p < 0.01). Regarding antiglycation activity, TBE showed significantly lower IC50 for dicarbonyl (2.03 ± 0.21 μg/mL) and AGEs (16.56 ± 4.44 μg/mL) than TCE (4.15 ± 0.20 μg/mL and 37.71 ± 1.14 μg/mL), indicating stronger antiglycation activity (p < 0.05). Moreover, TBE demonstrated greater effectiveness in both SO scavenging and ferric ion chelation assays (p < 0.05). In the α-glucosidase inhibition assay, both extracts exhibited superior efficacy compared to the standard acarbose (p < 0.01). These findings suggest that TBE possesses strong antiglycation, antioxidation, and α-glucosidase inhibitory activities, indicating its potential as a natural agent for managing oxidative stress-related diabetic complications. Further research is warranted to explore its mechanisms and therapeutic applications. (249 words)