Pilot Evaluation of <i>Dialium guineense</i> Fruit and Leaf Extracts in Inhibition of Glucose-Induced Protein Glycation and DPPH Radical: An <i>In vitro</i><i> </i>Study

Abstract

Advanced glycation end-products (AGEs) are the final products derived from the Maillard reaction, a non-enzymatic glycation of free amino groups by sugars and aldehydes. AGE formation begins under hyperglycemic or oxidative stress conditions. This work aimed to determine the anti-glycation and antioxidant potential of leaves and fruit pulp of Dialium guineense (black velvet tamarind). Plant materials were extracted with chloroform, methanol, and ethyl acetate using the maceration technique. Qualitative phytochemical screening was carried out alongside in vitro antioxidant assay (DPPH radical scavenging) and anti-glycation assay via the BSA-glucose model using spectrofluorescence, with aminoguanidine as the positive control. All experiments were carried out in triplicate, with data presented as mean ± standard deviation (SD), and analyzed using one-way analysis of variance (ANOVA) in SPSS version 20. Phytochemicals identified include saponins, cardiac glycosides, steroids, triterpenes, flavonoids and tannins. Antioxidant activity showed that the DG methanol leaf extract had the highest activity (72.44% at 250 µg/mL), which was highly significant (p < 0.05) compared to the control (92.01%). For the fruit pulp, the chloroform fruit extract had the highest activity (67.09% at 500 µg/mL). Anti-glycation activity of DG leaves showed that the methanol leaf extract had the highest activity (86.46% at 125µg/mL); for the fruit pulp, ethylacetate fruit extract had the highest activity (95.62% at 250µg/mL), which was highly significant (p < 0.05) compared to the control (83.68%). Despite the remarkable outcome achieved, some limitations of this pilot study include the exclusion of quantitative phytochemical analysis and other assay variants, and the scope being confined to an in vitro medium. In conclusion, the dual potential of both fruits and leaves of Dialium guineense in anti-glycation and antioxidant studies adds to its pharmacological value as a potential functional food or medicinal plant.