Structure-antioxidant relationship of flavonoids from fermented rooibos

Mol Nutr Food Res. 2009 May;53(5):635-42. doi: 10.1002/mnfr.200800117.


Rooibos tea (Aspalathus linearis) contains different bioactive phenolic compounds such as dihydrochalcones, flavonols, flavanones, flavones, and flavanols. Flavonoids isolated from rooibos were subjected to different in vitro assays: Trolox equivalent antioxidant activity, LDL oxidation and Fremy's salt assays to determine the total antioxidant activity (TAA). Assay results were compared, and the structure-antioxidant relationship was investigated. A decoupled LDL oxidation test was established with the objective of having an assay adapted more to an in vivo situation. The different in vitro methods were coupled offline to HPLC-DAD. Results from these coupled offline methods were compared to the TAA to assess the usefulness of the coupling setup.

MeSH terms

  • Antioxidants / pharmacology*
  • Aspalathus / chemistry*
  • Fermentation*
  • Flavonoids / pharmacology*
  • Humans
  • Lipoproteins, LDL / metabolism
  • Oxidation-Reduction
  • Plant Extracts / pharmacology*
  • Structure-Activity Relationship


  • Antioxidants
  • Flavonoids
  • Lipoproteins, LDL
  • Plant Extracts
  • oxidized low density lipoprotein