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Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
How relevant are flavonoids as antioxidants in plants?
Iker Hernández1, Leonor Alegre, Frank Van Breusegem
1Department of Plant Systems Biology, Ghent University, 9052 Gent, Belgium. ikher@psb.vib-ugent.be
Trends in Plant Science
|February 24, 2009
Summary
Flavonoids show strong antioxidant capacity in lab tests, but their actual antioxidant role in plants remains debated due to limited experimental evidence. Further research is needed to confirm their function in plant stress responses.
Area of Science:
- Plant Biochemistry
- Phytometabolomics
- Oxidative Stress Biology
Background:
- Flavonoids are plant secondary metabolites known for potent in vitro antioxidant activity.
- Their antioxidant efficacy in vitro surpasses that of vitamins C and E.
- Despite in vitro success, in vivo evidence for plant antioxidant function is scarce.
Purpose of the Study:
- To evaluate the experimental evidence supporting the antioxidant role of flavonoids in plants.
- To address the discrepancy between in vitro antioxidant capacity and in vivo function.
- To critically assess the current debate on flavonoid antioxidant activity in plants.
Main Methods:
- Review and synthesis of existing experimental data on flavonoid antioxidant function in plants.
- Analysis of studies investigating flavonoid accumulation under oxidative stress.
- Examination of the correlation between flavonoids and their oxidation products in planta.
Main Results:
- Flavonoids exhibit strong electron and hydrogen donating capacities in vitro.
- Experimental evidence for antioxidant function in plants is limited to specific conditions.
- Flavonoids accumulate during oxidative stress, but a clear spatio-temporal link with oxidation products is missing.
Conclusions:
- The widely accepted antioxidant role of flavonoids in plants is not yet conclusively proven.
- More robust experimental evidence is required to validate flavonoid antioxidant function in vivo.
- The debate on the physiological significance of flavonoid antioxidants in plants continues.
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