Two‐dimensional NMR analysis of Angiopteris evecta rhizome and improved extraction method for angiopteroside

Abstract

Introduction The rhizome of Angiopteris evecta is of academic interest in Kalimantan, Indonesia, from an ethnobotanical perspective. Angiopteroside is a substance of pharmaceutical importance that is found in the rhizome of A. evecta. Objective The aims of this research are to improve the extraction method for angiopteroside from the rhizome, compared to that in a previous report, and to determine the yield of angiopteroside from the rhizome of A. evecta, as well as to obtain precise data for extractives from the rhizome of A. evecta by using two‐dimensional NMR spectroscopy and liquid chromatography–mass spectrometry (LC–MS). Methodology We investigated the chemical constituents of the whole rhizome by means of two‐dimensional NMR (heteronuclear single quantum coherence or HSQC) spectroscopy, neutral sugar analysis using the alditol acetate method, and lignin analysis using alkaline nitrobenzene oxidation and Klason lignin methods. LC–MS revealed the purity of the angiopteroside. Antimicrobial assays were also performed for the purified angiopteroside by using a broth microdilution method. Results Angiopteroside was isolated by Soxhlet extraction with aqueous acetone followed by preparative thin‐layer chromatography (eluent: 20% methanol/dichloromethane). LC–MS revealed that angiopteroside can be found in the rhizome of A. evecta in 9.9% yield, which is an extremely high yield for a plant extractive. Conclusion HSQC analysis is a powerful tool for surveying compounds in plant materials, such as the whole rhizome of A. evecta. Soxhlet extraction with aqueous acetone is an effective method for extracting glycosides from plant materials.

Antioxidant and Antibacterial Activities Evaluation, Phytochemical Characterisation of Rhizome from Angiopteris helferiana and Barks from Saurauia fasciculata in Nepal

“…Previously, Lamichhane et al reported the angiopteroside from the yellow cultivar of A. helferiana [ 4 ]. Likewise, the authors in [ 30 , 31 ] revealed significant antibacterial activity of angiopteroside against E. coli . Therefore, the potent antibacterial activity of the red cultivar of A. helferiana might be due to the angiopteroside.…”

Natural products isolation studies of native Australian fern species

“…[59] Natural products 38 and 39 have been isolated from the fern species A. esculenta [60] and angiopteroside, an epimer of osmundalin (40), was isolated from Angiopteris evecta. [61] 4β-Carboxymethyl-(−)-epicatechin (42), [62] was isolated from Polystichum vestitum. This secondary metabolite has been isolated from Davallia divaricata, [62] D. solida [63] and Dryopteris crassirhizoma.…”

Anti-Adipogenic and Anti-Inflammatory Activities of (−)-epi-Osmundalactone and Angiopteroside from Angiopteris helferiana C.Presl

“…Hoffm. [33][34][35], and Angiopteris esculenta Ching [26]. Its diasteromer osmundalin, a glucoside of (−)-osmundalactone, was reported from a fern, Osmunda japonica, and it showed stimulating effect on the deterrent cell of Bombyx mori [29,36].…”