Inhibition of Alpha-Glucosidase and Antioxidant Test of Stem Bark Extracts of Garcinia fruticosa Lauterb

Abstract

Introduction: Diabetes mellitus (DM) is one of the global health emergencies that characterized by high blood glucose levels (hyperglycemia). Type 2 DM is the most common type in diabetic populations. Inhibition of alphaglucosidase can ameliorate postprandial hyperglycemia that occurs in patients with type 2 DM. Adding antioxidants to the therapy of DM is intended to reduce complications caused by oxidative stress. Some species of Garcinia have been proven to inhibit alpha-glucosidase and have antioxidant activity, but there is no research on Garcinia fruticosa Lauterb. Therefore, the aims of this research were to determine the activity of Garcinia fruticosa Lauterb. stem bark in inhibiting alpha-glucosidase and as an antioxidant. Methods: In this research, the Garcinia fruticosa Lauterb. stem bark was dried, grinded, and extracted by multistage maceration using n-hexane, ethyl acetate, and methanol. Inhibition of alpha-glucosidase test has been done in vitro on concentrated extracts and measured by microplate reader at 400 nm. The antioxidant test has been done using DPPH scavenging method and was measured by microplate reader at 519 nm. Results: Ethyl acetate extract is the most active extract for both test. IC 50 values for inhibition of alpha-glucosidase test are 20.18 µg/mL that is more active than standard (acarbose) which has IC 50 value 141.55 µg/mL. Meanwhile, IC 50 value from an antioxidant test is 8.93 µg/mL that is not more active than standard (quercetin) which has IC 50 value 2.51 µg/mL. Conclusion: Phytochemical screening shows that the ethyl acetate extract contains alkaloids, flavonoids, glycosides, saponins, and tannins.

“Diabetes and Metabolism Disorders Medicinal Plants: A Glance at the Past and a Look to the Future 2018”: Antihyperglycemic Activity of Hamelia patens Jacq. Extracts

“…patens manifest better α -glucosidase inhibitory effect with IC 50 = 26.07 μ g/ml and 30.18 μ g/ml, respectively, than dichloromethane-ethyl acetate and methanol-water extracts which did not exhibit activity. Their results coincide with those reported by other authors, who have demonstrated that high polarity extracts are more active than acarbose [ 35 – 37 ].…”

Phytochemical Screening, Total Flavonoid and Total Phenolic Content and Antioxidant Activity of Different Parts of Caesalpinia bonduc (L.) Roxb

“…Test was conducted in a 96-well plate according to Zahratunnisa et al 21 with slight modification. 20 µL stock solution of extracts in different concentrations (100, 500, 1000, 1500, 2000 ppm) and 180 µL of DPPH solution 0.147 mM were added to each well.…”

Fractionation and α-glucosidase Inhibitory Activity of Fractions from Garcinia hombroniana Pierre Leaves Extracts

“…Two fractions with the higher percent inhibition compared to other factions are fraction 8 from ethyl acetate extract (FEA8) and fraction 3 from methanol extract (FM3), their TLC profile is shown in Figure 1 and their percent inhibition in various concentrations shown in Table 3. FEA8 became the most have α-glucosidase inhibitory activity, 9,10 but further studies to obtain the active fraction that has α-glucosidase inhibition activity has not been done. The aim of the study is to separate active fraction in the crude extract of G. hombroniana leaves to facilitate obtaining a pure biologically active compound as the α-glucosidase inhibitor.…”