In vitro study on the antioxidant activity of a polyphenol-rich extract from Pinus brutia bark and its fractions

J Med Food. 2013 Nov;16(11):984-91. doi: 10.1089/jmf.2013.0050. Epub 2013 Nov 6.

Abstract

A crude hydromethanolic extract from Pinus brutia bark and its fractions (diethyl ether, ethyl acetate, n-butanol, and aqueous fractions) were studied with regard to their phenolic content and antioxidant activities. The total phenolics and proanthocyanidins in each extract were quantified by spectrophotometric methods; the polyphenolic profile was analyzed by RP-HPLC-DAD-ESI-MS. All extracts were tested with regard to their ability to scavenge free radicals (ABTS radical cation, superoxide and hydroxyl radicals), reduce ferric ions, and inhibit 15-lipoxygenase. P. brutia bark extracts had high phenolic contents (303.79±7.34-448.90±1.39 mg/g). Except diethyl ether extract, all other extracts contained proanthocyanidins ranging from 225.79±3.94 to 250.40±1.44 mg/g. Several polyphenols were identified by RP-HPLC-DAD-ESI-MS: taxifolin in diethyl ether extract, a taxifolin-O-hexoside, catechin, procyanidin dimers, and trimers in ethyl acetate extract. Except diethyl ether extract, all other extracts were effective scavengers of superoxide and hydroxyl radicals (EC₅₀=33.5±1.1-54.93±2.85 μg/mL and 0.47±0.06-0.6±0.0 mg/mL, respectively). All extracts had noticeable 15-lipoxygenase inhibitory effects (EC₅₀=22.47±0.75-34.43±2.25 μg/mL). We conclude that P. brutia bark is very promising for the dietary supplements industry due to its high free radical scavenging and 15-lipoxygenase inhibitory effects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antioxidants / analysis
  • Antioxidants / pharmacology*
  • Arachidonate 15-Lipoxygenase / metabolism*
  • Enzyme Inhibitors / analysis
  • Enzyme Inhibitors / pharmacology*
  • Free Radicals / metabolism*
  • Pinus / chemistry*
  • Plant Bark / chemistry
  • Plant Extracts / pharmacology*
  • Polyphenols / analysis
  • Polyphenols / pharmacology*

Substances

  • Antioxidants
  • Enzyme Inhibitors
  • Free Radicals
  • Plant Extracts
  • Polyphenols
  • Arachidonate 15-Lipoxygenase