Stability and antioxidant activity of semi-synthetic derivatives of 4-nerolidylcatechol

Molecules. 2012 Dec 24;18(1):178-89. doi: 10.3390/molecules18010178.

Abstract

4-nerolidylcatechol (4-NC) is an unstable natural product that exhibits important antioxidant, anti-inflammatory and other properties. It is readily obtainable on a multi-gram scale through straightforward solvent extraction of the roots of cultivated Piper peltatum or P. umbellatum, followed by column chromatography on the resulting extract. Semi-synthetic derivatives of 4-NC with one or two substituent groups (methyl, acetyl, benzyl, benzoyl) on the O atoms have been introduced that have increased stability compared to 4-NC and significant in vitro inhibitory activity against the human malaria parasite Plasmodium falciparum. Antioxidant and anti-inflammatory properties may be important for the antiplasmodial mode of action of 4-NC derivatives. Thus, we decided to investigate the antioxidant properties, cytotoxicity and stability of 4-NC derivatives as a means to explore the potential utility of these compounds. 4-NC showed high antioxidant activity in the DPPH and ABTS assays and in 3T3-L1 cells (mouse embryonic fibroblast), however 4-NC was more cytotoxic (IC₅₀ = 31.4 µM) and more unstable than its derivatives and lost more than 80% of its antioxidant activity upon storage in solution at -20 °C for 30 days. DMSO solutions of mono-O-substituted derivatives of 4-NC exhibited antioxidant activity and radical scavenging activity in the DPPH and ABTS assays that was comparable to that of BHA and BHT. In the cell-based antioxidant model, most DMSO solutions of derivatives of 4-NC were less active on day 1 than 4-NC, quercetin and BHA and more active antioxidants than BHT. After storage for 30 days at -20 °C, DMSO solutions of most of the derivatives of 4-NC were more stable and exhibited more antioxidant activity than 4-NC, quercetin and BHA and exhibited comparable antioxidant activity to BHT. These findings point to the potential of derivatives of 4-NC as antioxidant compounds.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Animals
  • Antimalarials / chemistry
  • Antimalarials / pharmacology*
  • Antioxidants / chemistry
  • Antioxidants / pharmacology*
  • Butylated Hydroxyanisole / chemistry
  • Butylated Hydroxyanisole / pharmacology
  • Butylated Hydroxytoluene / chemistry
  • Butylated Hydroxytoluene / pharmacology
  • Catechols / chemistry*
  • Catechols / pharmacology*
  • Cell Survival / drug effects
  • Inhibitory Concentration 50
  • Malaria / drug therapy
  • Mice
  • Nonlinear Dynamics
  • Piper / chemistry*
  • Plant Roots / chemistry
  • Plasmodium falciparum / drug effects
  • Plasmodium falciparum / growth & development

Substances

  • 4-nerolidylcatechol
  • Antimalarials
  • Antioxidants
  • Catechols
  • Butylated Hydroxytoluene
  • Butylated Hydroxyanisole