Flavanones from Erythrina crista-galli Twigs and Their Antioxidant Properties Determined through In Silico and In Vitro Studies

Abstract

Flavonoids are a secondary metabolite group with various bioactivities, such as antioxidants. They are rich in the genus Erythrina, such as Erythrina crista-galli. This research aims to isolate and characterize flavonoids from the twigs of E. crista-galli and determine their antioxidant properties through in silico and in vitro assays. The ethyl acetate extract of E. crista-galli twigs were separated by column chromatography and characterized using spectroscopic methods. Density functional theory (DFT) calculations were performed on the isolated flavonoids and the reference compounds (ascorbic acid and quercetin) to obtain global descriptive parameters and a donor–acceptor map (DAM). We successfully isolated lupinifolin (1) and citflavanone (2) for the first time from E. crista-galli, along with lonchocarpol A (3), which has been discovered previously. The DAM suggests that these flavanones are good antiradicals with effective electron donors. However, they tend to be electron acceptors in methanol. The frontier molecular orbital analysis implies that lupinifolin (1) is a better antiradical than the other flavanones. The DPPH assays show that lupinifolin (1) has the highest antioxidant (antiradical) activity, with an IC50 value of 128.64 ppm. The in silico studies showed similar trends to the in vitro assays using the DPPH method.

Pharmacology activity, toxicity, and clinical trials of Erythrina genus plants (Fabaceae): an evidence-based review

“…The ethyl acetate fraction and lupinifolin, a flavanone isolated from E. crista-galli L. twigs collected in Cihideung, West Java, Indonesia, have confirmed its capability to scavenge 50% of the initial DPPH radicals with a value of 64.41 and 128.64 μg/mL, respectively, better than the other flavanones, e.g., citflavanone and lonchocarpol A. It was explained that the prenyl and the pyran in lupinifolin contribute to this capability (Deviani et al, 2022). Silver nanoparticles (Ag-NPs) synthesized from the leaf and bark extracts of E. suberosa Roxb.…”

“…The Erythrina genus of the family Fabaceae includes trees, shrubs, and herbaceous plants with orange to bright red flowers, rich in pterocarpans and alkaloids (Rukachaisirikul et al, 2007a;Phukhatmuen et al, 2021), flavonoids (Nyandoro et al, 2017;Deviani et al, 2022;Simão et al, 2022), triterpenes, steroids, alkyl trans-ferulates, proteins, saponins, and lecithin (Kumar et al, 2010), gallic and caffeic acids (Muthukrishnan et al, 2016). Pterocarpans comprise a large group of isoflavonoids and function as phytoalexins (plant antimicrobial mechanism) and are mostly found in the Leguminosae (Fabaceae) family (Jiménez- González et al, 2011).…”

“…The radical scavenging activity of Erythrina genus plants has been verified by employing various methods, such as ferrous reducing antioxidant capacity (FRAC) (Afzal et al, 2022), 2,2diphenyl-1-picrylhydrazyl (DPPH) radical (Dzoyem et al, 2014;Deviani et al, 2022;Fofana et al, 2022), and 2,2′-azino-bis (3ethylbenzothiazoline-6-sulphonic acid) diamonium salt (ABTS) (Dzoyem et al, 2014).…”

Computational Chemistry Strategies to Investigate the Antioxidant Activity of Flavonoids—An Overview

“… The basic skeleton of the subclasses to which the investigated compounds belong, along with the number of compounds in each subclass that have been studied over the past five years [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 ...…”

“… The methods employed in the past five years to investigate the electronic structure of flavonoids, along with the proportion of each method used [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , …”