Genetic Variation of Plant Antioxidants
Ric de Vos, Jules Beekwilder, Robert Hall, Jan Schaart, Harry Jonker and Arnaud Bovy
Plant Research International,
B.U. Bioscience
Wageningen UR
Wageningen, The Netherlands
Plants and their products are generally known for their high levels of antioxidants, which may contribute to the positive effects of dietary plant products for human health. However, the hydrophilicity, free radical scavenging activities as well as bioavailability of natural antioxidants all depend on their exact chemical structure. The level and structure of antioxidants are determined by the activity of the various biosynthetic enzymes involved in a given metabolic pathway as well as of enzymes catalyzing subsequent modifications, such as methylation and glycosylation, in the plant cell.
In this presentation, the role of the genetic background in the levels of antioxidant compounds in plant tissue will be discussed. By screening large sets of different genotypes of various plant species for a range of antioxidants, we identified marked differences between genotypes in the qualitative and quantitative production of antioxidants. This information can be used in selection and breeding of plants accumulating high levels of specific antioxidants. In addition, examples will be presented of exploiting and using the natural genetic variation in antioxidant-modifying enzymes, in order to modify the structure and thereby their bioactivity and/or bioavailability of plant antioxidants.
Dr. Ric de Vos is working as a senior-researcher at Plant Research International (PRI) at Wageningen, The Netherlands, and a specialist in plant physiology and biochemistry. His main interest is the identification and regulation of plant metabolites with presumed health-protecting or toxic effects in human. He has more than 20 years of research experience in extraction, separation and identification of plant compounds, specifically antioxidants such as flavonoids. At PRI he developed an on-line HPLC antioxidant detection system to screen and compare plant extracts for both water-soluble and lipid-soluble antioxidants. His current research is mainly focused on setting up and implementing large-scale metabolomics approaches based on high resolution mass spectrometry.