Evaluation of phytochemical profile, and antioxidant, antidiabetic activities of indigenous Thai fruits

Abstract

Background This research aims to explore the phenolics identification, phenolics quantification, antioxidant and potential biofunctional properties of lesser-known Thai fruits and their potency to treat type 2 diabetes mellitus (T2DM). Including, Antidesma puncticulatum, Dillenia indica, Diospyros decandra, Elaeagnus latifolia, Flacourtia indica, Garcinia dulcis, Lepisanthes fruticose, Mimusops elengi, Muntingia calabura, Phyllanthus reticulatus, Streblus asper, Syzygium cumini, Syzygium malaccense, Willughbeia edulis and Schleichera oleosa were analyzed by their phenolic and flavonoid content. These fruits have received limited scientific attention, prompting an investigation into their health benefits, particularly their relevance to diabetes management. Methods The study utilized methanolic crude extracts to measure phenolic and flavonoid levels. Additionally, UHPLC-DAD was utilized to identify and quantify phenolics. The methanolic extracts were assessed for antioxidant and antidiabetic abilities, including α-glucosidase and α-amylase inhibition. Results and Conclusion The study highlighted S. cumini as a rich source of phenolic (980.42 ± 0.89 mg GAE/g and flavonoid (3.55 ± 0.02 mg QE/g) compounds with strong antioxidant activity (IC50 by DPPH; 3.00 ± 0.01 µg/ml, IC50 by ABTS; 40 ± 0.01 µg/ml, FRAP; 898.63 ± 0.02 mg TE/ml). Additionally, S. cumini exhibited promising antidiabetic effects (S. cumini IC50; 0.13 ± 0.01 mg/ml for α-glucosidase inhibition, 3.91 ± 0.05 mg/ml for α-amylase inhibition), compared to Acarbose (IC50; 0.86 ± 0.01 mg/ml for α-glucosidase inhibition, 0.39 ± 0.05 mg/ml for α-amylase inhibition). Remarkably, compounds like catechins, gallic acid, kaempferol, and ellagic acid were identified in various quantities.This study suggests that these fruits, packed with phenolics, hold the potential to be included in an anti-diabetic diet and even pharmaceutical applications due to their health-promoting properties.