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Updated: Jun 27, 2026
09:50
Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
Antioxidative flavonoids from Cleistocalyx operculatus buds.
Byung-Sun Min1, Cao Van Thu, Nguyen Tien Dat
1College of Pharmacy, Catholic University of Daegu, Gyeongsan, Korea. bsmin@cu.ac.kr
Chemical & Pharmaceutical Bulletin
|December 2, 2008
Summary
Four new flavonoids were identified in Cleistocalyx operculatus buds. Two compounds demonstrated significant antioxidant activity, scavenging free radicals effectively.
Area of Science:
- Natural Product Chemistry
- Phytochemistry
- Medicinal Chemistry
Background:
- Cleistocalyx operculatus (Myrtaceae) is a plant species known for its potential medicinal properties.
- Flavonoids are a class of plant secondary metabolites with diverse biological activities, including antioxidant properties.
Purpose of the Study:
- To isolate and characterize new flavonoid compounds from the buds of Cleistocalyx operculatus.
- To evaluate the antioxidant potential of the isolated compounds.
Main Methods:
- Isolation of compounds using chromatographic techniques.
- Structure elucidation of new metabolites utilizing spectroscopic analyses, including 2D NMR.
- Assessment of radical scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay.
Main Results:
- Four novel flavonoids were successfully isolated and identified: 3'-formyl-4',6',4-trihydroxy-2'-methoxy-5'-methylchalcone (1), 3'-formyl-6',4-dihydroxy-2'-methoxy-5'-methylchalcone 4'-O-beta-D-glucopyranoside (2), (2S)-8-formyl-6-methylnaringenin (3), and (2S)-8-formyl-6-methylnaringenin 7-O-beta-D-glucopyranoside (4).
- Compounds 1 and 3 exhibited significant 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, with IC(50) values of 22.8 microM and 27.1 microM, respectively.
Conclusions:
- The study successfully identified four new flavonoids from Cleistocalyx operculatus buds.
- The findings highlight the potential of these novel flavonoids as antioxidants, warranting further investigation into their therapeutic applications.
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