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Updated: Jun 19, 2026
11:56
A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
Covalent interaction of ascorbic acid with natural products
Nicholas G Kesinger1, Jan F Stevens
1Department of Pharmaceutical Sciences, The Linus Pauling Institute, Oregon State University, Corvallis, OR 97331, USA.
Phytochemistry
|October 31, 2009
Summary
Ascorbylation, the covalent bonding of vitamin C (ascorbic acid) with natural products, is a newly recognized phenomenon. This study surveys 33 such compounds and their biological activities.
Area of Science:
- Natural Product Chemistry
- Biochemistry
- Organic Chemistry
Background:
- Ascorbic acid (vitamin C) is primarily recognized for its roles as a cofactor and antioxidant.
- Emerging research indicates ascorbic acid forms covalent bonds with natural products, a process termed 'ascorbylation'.
- Ascorbylated natural products have been isolated from diverse sources, including marine algae and plants.
Purpose of the Study:
- To survey and characterize known ascorbylated natural products.
- To investigate the formation mechanisms of these compounds.
- To review the reported biological activities of ascorbylated natural products.
Main Methods:
- Literature review of isolated and characterized ascorbylated natural products.
- Analysis of chemical structures and formation pathways.
- Compilation of reported biological activities.
Main Results:
- Identified and reviewed 33 distinct ascorbylated natural products.
- Detailed common formation mechanisms, including nucleophilic substitution/addition and electrophilic addition.
- Highlighted examples such as ascorbigens, ascorbylated tannins, and annulations with polyphenols like EGCG and resveratrol.
Conclusions:
- Ascorbylation represents a significant, yet underappreciated, modification of natural products.
- These compounds exhibit diverse biological activities, warranting further investigation.
- Understanding ascorbylation provides new insights into natural product biosynthesis and function.
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