Pharmacognostic evaluation of Eranthemum indicum extracts for its in-vitro antioxidant activity, acute toxicology, and investigation of potent bioactive phytocompounds using HPTLC and GCMS

Abstract

BackgroundNortheast India has a rich resource of herbal plants, and it is essential to validate their therapeutic activity with proper scientific evidence. This study aims to identify active phytocompounds found in the extracts of Eranthemum indicum (E. indicum) and to determine its antioxidative activities and toxicity.ResultsIn vitro free radical scavenging activity of the aqueous extract (AE) and methanol extract (ME) of E. indicum (leaves) was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic-acid (ABTS), ferric reducing antioxidant power (FRAP), and total antioxidant activity (TAC). ME depicted better inhibitory concentration when compared to AE. This indicates the effective extraction capacity of methanol, which is consistent with the fact that ME had a higher polyphenol and flavonoid, resulting in their antioxidative activity. HPTLC analysis using the solvent system of ethyl acetate/methanol/ammonia 28–30% (40:10:10) showed better fingerprinting separation, especially in the ME. Furthermore, DPPH radical solution, when used as a derivatizing agent in HPTLC analysis, confirmed that ME has better in vitro antioxidant activities than AE. GCMS analysis of AE identified 3-beta-hydroxy-5-cholen-24-oic-acid as active compound, while in ME Beta.-l-arabinopyranoside and 2-methyl-3-(3-methyl-but-2-enyl)-2-(4-methyl-pent-3-enyl)-oxetane were identified as the major bioactive compound. Acute toxicological investigations have shown that both E. indicum extracts have a high L.D. 50 value of 1533 mg/kg b.w for AE and 1567 mg/kg b.w for ME making them safe and non-toxic.ConclusionsExtraction and identification of these phytocompounds in the extracts of E. indicum can help us scientifically document its medicinal importance, and its benefit in pharmaceutical industries. Since it showed promising free radical scavenging activity, it can also be a potent antioxidant source.