BACKGROUND

has been reported to possess a variety of pharmacological activities traditionally. Previous work suggested its antidiabetic properties, but information on the antidiabetic compounds is still lacking.

OBJECTIVE

The present research exertion was aimed to isolate and identify biologically active polyphenols from leaves and to evaluate their efficacy on carbohydrate digesting enzymes.

MATERIALS AND METHODS

Fractionation of the polyphenolic contents from the methanolic extract of leaves was executed by the silica gel column chromatography to yield different fractions. The antioxidant activities of these fractions were carried out against 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazyl radicals, and ferric ion-reducing antioxidant power (FRAP). antidiabetic experimentation was performed by evaluating the α-amylase and α-glucosidase inhibitory capacity. The isolated polyphenols were then identified using liquid chromatography and mass spectroscopy (LC/MS).

RESULTS

Out of the eight polyphenolic fractions (BAL 1-8), BAL-4 has the highest inhibitory activity against ABTS radicals whereas BAL-6 showed potent ferric ion-reducing capacity. BAL-5 was the most effective fraction with antidiabetic activity with ICof 140.0 and 68.58 ± 3.2 μg/ml for α-amylase and α-glucosidase inhibitory activities, respectively. All the fractions competitively inhibited α-amylase, BAL-5 and BAL-6 also inhibited α-glucosidase competitively, while BAL-4 and BAL-1 exhibited noncompetitive and near competitive inhibitions against α-glucosidase, respectively. The LC/MS analysis revealed the presence of carvone in all the fractions.

CONCLUSIONS

The present study demonstrates the antioxidant and antidiabetic activities of the isolated polyphenols from .

SUMMARY

Polyphenols were successfully isolated and identified from leavesThe isolated polyphenols are biologically active with high antioxidant as well as inhibitor of carbohydrate-digesting enzymes can be a good source of amylase and glucosidase inhibitors can be used as complementary or alternative therapeutic agents especially for the treatment of diabetesCarvone, quercetin, and psoralen could be the compounds responsible for the α-amylase and α-glucosidase inhibitory activities. ABTS: 2,2'-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid), DPPH: 2,2-diphenyl-1-picrylhydrazyl, FRAP: Ferric ion-reducing antioxidant power, LC/MS: Liquid chromatography and mass spectroscopy, AGEs: Advanced glycation end products, TLC: Thin-layer chromatography, MeOH: Methanol, PNP-G: ρ-Nitrophenyl-α-D-Glucoside, : Coefficient of determination, mgQE: Milligram quercetin equivalent, mgTAE: Milligram tannic acid equivalent, mgCE: Milligram catechin equivalent, g: Gram.