Bioassay-guided isolation of proanthocyanidins with antioxidant activity from peanut (Arachis hypogaea) skin by combination of chromatography techniques

Abstract

Purification and bioassay-guided fractionation were employed to isolate proanthocyanidins with antioxidant activity from peanut skin (Arachis hypogaea Runner 886). The crude extract was prepared with acetone (60% v/v) and purified using chromatographic methods, including a semipreparative HPLC technique. As a result, two proanthocyanidins were isolated and identified using NMR, epicatechin-(2 β → O → 7, 4 β → 8)-catechin (proanthocyanidin A1) and epicatechin-(β → 2 O → 7, 4 β → 8)-epicatechin (proanthocyanidin A2). Despite the structural similarity, differences were observed in their antioxidant activity. Proanthocyanidin A1 proved to be more active, with EC50 value for DPPH radical scavenging of 18.25 μg/mL and reduction of Fe(3+)-TPTZ complex of 7.59 mmol/g, higher than that of synthetic antioxidant BHT. This compound evaluated by ABTS(+) was similar to that of natural quercetin. Therefore, peanut skin is an important source of bioactive compounds that may be used as a mild antioxidant for food preservation.

Can we conserve trans‐resveratrol content and antioxidant activity during industrial production of chocolate?

“…The antioxidant capacity was assessed applying the free radical ABTS method following the procedure recommended by Oldoni et al ., with some modifications. ABTS radical was prepared adding 5 mL of 7 mmol L –1 ABTS · + solution to 88 μL of 140 mmol L –1 potassium persulfate solution, incubated at 25 °C in the dark for 12–16 h. Once formed, the radical was diluted with 75 mmol L –1 potassium phosphate buffer, pH 7.4, to an absorbance of 0.700 ± 0.01 at 734 nm.…”

Gallic Acid: A Promising Lead Molecule for Drug Development

“…Some of the plant extract from which GA has been isolated are methanolic extract of whole plant of Bergia suffruticosa, aqueous ethanolic extract of leaves of Ceratonia siliqua, methanolic extract of the leaves of Tectona grandis as well as methanolic extracts of bark, wood, leaf and fruits of Casuarina equisetifolia [23][24][25]. A bioassay guided isolation and identification of gallic acid derivatives epicatechin-(2 β → O → 7, 4 β → 8)-catechin (proanthocyanidin A1) and epicatechin-(β → 2 O → 7, 4 β → 8)-epicatechin (proanthocyanidin A2) were reported from peanut skin [26].…”

Suppressive Effects of Pelargonidin on Endothelial Protein C Receptor Shedding via the Inhibition of TACE Activity and MAP Kinases

“…PEL and P3G have been reported to have anti-oxidant and antidiabetic activity in vivo (Hamalainen et al, 2007;Hidalgo et al, 2012;Kamenickova et al, 2013;Noda et al, 2002;Schmitt and Stopper, 2001). Recently, PEL and P3G were reported to have anti-inflammatory and anticarcinogenic activity, and also were shown to be effective in cardiovascular disease prevention and diabetes management (Oldoni et al, 2016;Zhu et al, 2015). However, to the best of our knowledge, the effects of PEL on EPCR shedding have not yet been studied.…”