Antioxidant activity of fractions from Quercus sideroxyla bark and identifi cation of proanthocyanidins by HPLC-DAD and HPLC-MS Public Deposited

http://ir.library.oregonstate.edu/concern/defaults/th83kz811

This is the publisher’s final pdf. The published article is copyrighted by Walter de Gruyter and can be found at:  http://www.degruyter.com/view/j/hfsg.

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • The most active phenolics in Quercus sideroxyla Humb. & Bonpl. residual bark were identified and evaluated following a chromatographic fractionation. Bark powder was defatted with hexane and crude extract (CE) was obtained by extraction with aqueous acetone (70%). A liquid partition with ethyl acetate was performed to produce an organic extract (OE), which was subsequently purified by column chromatography (Toyopearl HW-40F, methanol), and resulted in six methanolic fractions (MF1 to MF6) and an oligomeric fraction (OLF) eluted with acetone 67%. Extraction yields, total phenolic and flavanol contents were determined. The antioxidant activity of bark extracts was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox (6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic-acid)-equivalent antioxidant capacity (TEAC), and ferric ion reducing antioxidant power (FRAP) assays. Their median effective concentration (EC₅₀) data and rate constants for DPPH radical scavenging were also estimated. Identification of major phenolics was carried out by high performance liquid chromatography with diode array detection (HPLC-DAD) and high performance liquid chromatography with electrospray ionization coupled to mass spectrometry (HPLC-ESI-MS) instruments. Bioactive gallic acid, catechin, epicatechin, gallocatechin, catechin gallate, dimeric procyanidins, galloylated dimeric proanthocyanidins, trimeric procyanidins, and tetrameric proanthocyanidins were detected and identified in Q. sideroxyla bark extracts. MF2 was the most active fraction containing gallocatechin as its major compound; MF5 and OLF contain galloylated procyanidins, which may explain their higher antiradical activity. OLF besides galloylated procyanidins has gallocatechin, which presumably contributes to its higher antiradical activity. Consequently, Q. sideroxyla bark could be a good source of therapeutic health products or nutraceutical ingredients that may exert a potential prevention or treatment action against diseases in biological systems.
Resource Type
DOI
Date Available
Date Issued
Citation
  • Rosales-Castro, M., Gonzalez-Laredo, R., Rocha-Guzman, N., Gallegos-Infante, J., Rivas-Arreola, M., & Karchesy, J. (2012). Antioxidant activity of fractions from quercus sideroxyla bark and identification of proanthocyanidins by HPLC-DAD and HPLC-MS. HOLZFORSCHUNG, 66(5), 577-584. doi: 10.1515/hf-2011-0157
Academic Affiliation
Series
Keyword
Rights Statement
Funding Statement (additional comments about funding)
Publisher
Peer Reviewed
Language
Replaces
Additional Information
  • description.provenance : Made available in DSpace on 2012-09-24T18:16:33Z (GMT). No. of bitstreams: 1 KarchesyJosephForestryAntioxidantActivityFractions.pdf: 402819 bytes, checksum: 031f85aad82d5002786458f1d1b177c9 (MD5) Previous issue date: 2012-07
  • description.provenance : Submitted by Deanne Bruner (deanne.bruner@oregonstate.edu) on 2012-09-21T23:32:06Z No. of bitstreams: 1 KarchesyJosephForestryAntioxidantActivityFractions.pdf: 402819 bytes, checksum: 031f85aad82d5002786458f1d1b177c9 (MD5)
  • description.provenance : Approved for entry into archive by Deanne Bruner(deanne.bruner@oregonstate.edu) on 2012-09-24T18:16:33Z (GMT) No. of bitstreams: 1 KarchesyJosephForestryAntioxidantActivityFractions.pdf: 402819 bytes, checksum: 031f85aad82d5002786458f1d1b177c9 (MD5)

Relationships

In Administrative Set:
Last modified: 07/06/2017

Downloadable Content

Download PDF
Citations:

EndNote | Zotero | Mendeley

Items