Antioxidant activities of different parts of Gnetum gnemon L.

Abstract

Analyses on biological activities of Gnetum gnemon were done to determine the total phenolic and antioxidants of the plant. Four parts of G. gnemon were used in this study, which were leaf, bark, twig, and seeds of the plant. All parts were extracted in methanol, ethanol, hexane, chloroform and hot water using reflux. The total phenolic content of the plant extracts were determined by using Folin-Ciocalteu method. The results demonstrated that the bark from hot water extract showed the highest total phenolic at 10.71±0.01 mg GAE/ FDW, while the lowest was chloroform extract of seed at 2.15±0.01 mg GAE/ FDW. The antioxidant activity of the plant extracts were determined by using DPPH and FRAP assays, respectively. The DPPH results showed that all plant extracts demonstrated weak free radical scavenging activity tested at the final concentration of 300 μg/ml. In contrast, the methanolic twig extract showed strong reducing power activity (FRAP) at 83.55±1.05%, while the hot water seed extract showed the least activity at 41.86±4.22% tested at the final concentration of 300 μg/ml. However, there were no correlation between total phenolics and both antioxidant assays tested.

Extraction of Resveratrol from Melinjo (<i>Gnetum gnemon L</i>.) Seeds Using Mixtures of Liquid Carbon Dioxide and Ethanol

“…This result shows that the eluent obtained at these pressures gave similar concentrations, implying that the yields of resveratrol were insensitive to the operating pressure for the liquid CO 2 and ethanol mixture (ethanol mole fraction x EtOH = 0.131). The effects of operating temperature and pressure on the extraction yield are similar to the extraction results for other liquid CO 2 mixtures [7,16,19,20]. Under these extraction conditions (temperature = 25 ºC, pressure = 8, 10, and 14 MPa), gas and liquid phages coexist in the extraction vessel.…”

“…The chemical structure of resveratrol is shown in Figure 1. Resveratrol and other stilbenoids compounds were extracted from melinjo seeds by using conventional organic solvents such as hexane, chloroform and ethyl acetate [1], ethanol [2], methanol, hexane and chloroform [7]. This research aims to show that resveratrol can be extracted by using a mixture of liquid carbon dioxide and ethanol.…”

Liquid Carbon Dioxide Extraction of Xanthones from the Pericarps of <i>Garcinia Mangostana</i> Linn. Enhanced by Ultrasonic Irradiation

“…It is considered that the amount of ethanol, as the cosolvent, decreases in the liquid CO 2 phase because the ethanol distributed more to the vapor-phase at 14MPa. The effects of operating temperature and pressure on the extraction yield are similar to the results of other liquid CO 2 extractions [16,[25][26][27][28]. Under these extraction conditions (temperature = 25 ºC, pressure = 8, 10, and 14 MPa), gas and liquid phases coexist in the extraction vessel.…”

Antioxidant, Antityrosinase and Antitumor Activity Comparison: The Potential Utilization of Fibrous Root Part of Bletilla striata (Thunb.) Reichb.f.

“…Ferric-reducing antioxidant power of Bletilla samples were measured using the assay described by Wazir et al [18]. About 0.5 ml of potassium phosphate buffer (0.2 M, pH 6.6) and 0.5 ml 1% potassium ferricyanide was thoroughly mixed with 0.3 ml Bletilla striata extracts.…”