Secondary Metabolite Fingerprinting and Antioxidant Potency of Eleusine indica: An Integrated Chromatography and In silico Investigation

Abstract

Natural regimens and constituents serve as the primary sources for drug conservation, and each herbal regimen possesses unique ethnomedicinal and biological properties. Therefore, researchers are currently more interested in exploring the biological activity of existing plant species with the most systematic approach to be used in the specific therapeutics proposed, either crude extracts or bioactive metabolites. The present study also explores the antioxidant potency of ethanolic extracts of Eleusine indica (a weed in an agricultural field) through chemical fingerprinting analyses through high-performance thin-layer chromatography (HPTLC), followed by gas chromatography-mass spectrometry (GCMS) and in silico investigation in a systematic way. Briefly, this investigation aims to observe the presence of secondary metabolites associated with antioxidant activity. After extraction, a fingerprint study was carried out with the mobile phase consisting of ethyl acetate, acetic acid, formic acid, and water in the ratio 10:1.1:1.1:2.3 by volume, where more than eight fluorescent and non-fluorescent bands were found, with the highest density peak area at Rf 0.87 and the lowest at Rf 0.18. As per the GCMS report ethanolic extracts of E. indica are composed of several metabolites. Further, based on the higher Rf value, we have selected seven (EI_1 to EI_7) that constitute molecular docking against three target enzymes: cyclooxygenase-2 (PDB ID: 5F1A), peroxiredoxin-5 (PDB ID: 1HD2), and haemoxygenase 1 (PDB ID: 3CZY) to assess the antioxidant potency. Overall, the results revealed that EI_7 (2,7-dioxatricyclo [4.4. 0.0(3,8)] decane-4,5-diol) showed similar potency with ideal drug-ability profiles similar to ascorbic acid and was considered a lead for further therapeutic use as a complementary agent.