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Molecular Modification of Polysaccharides and Resulting Bioactivities
Shijie Li1,2, Qingping Xiong3, Xiaoping Lai1,4
1School of Chinese Materia Medica, Guangzhou Univ. of Chinese Medicine, Guangzhou, 510006, Guangdong, PR China.
Comprehensive Reviews in Food Science and Food Safety
|December 29, 2020
Summary
Modified natural polysaccharides offer improved pharmaceutical and supplement benefits. Molecular changes enhance bioactivity, solubility, and antioxidant properties, making them valuable therapeutic agents.
Area of Science:
- Biochemistry
- Pharmacology
Background:
- Natural polysaccharides are valuable resources for pharmaceuticals and supplements.
- Their inherent properties limit direct comparison with synthetic drugs.
- Structure-activity relationship studies enable functional improvements.
Purpose of the Study:
- To review major polysaccharide modification methods.
- To discuss the impact of molecular modification on properties and bioactivities.
- To highlight common modifications and their effects.
Main Methods:
- Chemical modification: grafting groups to enhance solubility and bioactivity.
- Physical modification: altering molecular weight.
- Biological modification: altering molecular weight.
Main Results:
- Molecular modification enhances physicochemical properties and bioactivities.
- Antioxidant activity is commonly increased, especially via sulfation and acetylation.
- Phosphorylation increases antitumor activity; sulfation yields anti-HIV activity.
Conclusions:
- Polysaccharide modification is key to improving their therapeutic potential.
- Tailored modifications can yield enhanced antioxidant, antitumor, and antiviral activities.
- Modified polysaccharides represent promising candidates for drug development.
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