α-VINIFERIN as a potential antidiabetic and antiplasmodial extracted from Dipterocarpus littoralis

Abstract

Over the past few decades, complementary medicine therapy using medicinal plants have been developed in healthcare. Phytochemical studies about medicinal plants have been conducted to verify their potency as medicinal remedies in modern therapeutics. Dipterocarpus littoralis commonly known as Meranti Jawa in Indonesia is traditionally used to treat diseases such as diarrhea, diabetic and malaria. This study aimed to isolate bioactive compounds from D. littoralis using bioguided fractionation method. The bioactivity measured were antioxidant, antidiabetic, and antiplasmodial activity. Alpha-glucosidase and alpha-amylase assays were applied to estimate the in vitro antidiabetic activity of D. littoralis. The antioxidant activities were determined by using the free radical scavenging assays 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2-2 00 -azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Analysis of total flavonoid and phenolic contents were expressed as Quercetin Equivalent (QE) and Gallic Acid Equivalent (GAE), respectively. The in vitro antiplasmodial activity test of methanol extract of D. littoralis was also conducted against Plasmodium falciparum strain 3D7. Purification of the ethyl acetate fraction of the methanol extract of D. littoralis resulted in an oligostilbenes namely α-viniferin (1). The structure of the α-viniferin was characterized by comprehensive spectral analysis including IR, 1D and 2D NMR, and in comparison with the literature data. Compound 1 showed an alpha-glucosidase and alpha-amylase inhibitory activity with IC 50 values of 256.17 and 212.79 μg/mL, respectively. The in vitro antiplasmodial activity test against Plasmodium falciparum strain 3D7 at a concentration of 100 μg/mL revealed a strong antiplasmodial inhibitory activity with IC 50 value of 2.76 μg/mL. Our findings indicated that α-viniferin (1) which is isolated from D. littoralis extract could be regarded as potential antidiabetic and antiplasmodial resources in the future.

Antidiabetic, cytotoxic and antioxidant activities of Rhodomyrtus tomentosa leaf extracts

“…The anti-α-amylase assay was adapted from ref. 14 with a slight modification. Each sample (10 mg) was dissolved in 1 mL of DMSO and the α-amylase enzyme was prepared by dissolving 5 mg of porcine pancreas α-amylase in 1 mL of 0.1 M phosphate buffer (pH 6.9).…”

Biological Activity Evaluation and In Silico Studies of Polyprenylated Benzophenones from Garcinia celebica

“…The antioxidant activity was also evaluated with free radical ABTS (2,2″-azinobis (3-ethyl benzothiazoline-6-sulfonic acid) using the reported method [ 30 ]. For this evaluation, 5.0 mL of 7 mM ABTS stock solution were mixed with 88 μL of 140 mM potassium peroxydisulfate (K 2 S 2 O 6 ) and stored in the dark at room temperature for 12–16 h before use.…”

Evaluation of the Antioxidant, Antidiabetic, and Antiplasmodial Activities of Xanthones Isolated from Garcinia forbesii and Their In Silico Studies

“…The antioxidant activity of isolated xanthones 1-5 was assayed by DPPH, ABTS and FRAP methods. DPPH is known for its stability and free radicals scavenging activity [26]. A radical species containing nitrogen atoms of ABTS stabilizes the free radicals through proton donors [27].…”