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Updated: Aug 3, 2025
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A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes
Published on: June 10, 2022
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Characterization of phenolic constituents in hazelnut kernels
Takashi Uchikura1, Tomoe Kitano1, Morio Yoshimura1
1Department of Pharmacognosy, College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime, Japan.
Bioscience, Biotechnology, and Biochemistry
|April 10, 2023
Summary
This study identified new phenolic compounds in hazelnuts, including novel acetophenone glycosides and condensed tannins. These hazelnut extracts demonstrated significant antioxidant activity, highlighting their potential health benefits.
Area of Science:
- Phytochemistry
- Nutritional Science
- Food Chemistry
Background:
- Hazelnuts (Corylus avellana L.) are recognized for their nutritional value and contain bioactive phenolic compounds.
- Phenolic compounds contribute to the health benefits and antioxidant properties of foods.
Purpose of the Study:
- To isolate and characterize phenolic compounds from hazelnut kernels.
- To investigate the antioxidant activity of high-molecular-mass condensed tannins from hazelnuts.
Main Methods:
- Isolation and spectral analysis of phenolic compounds.
- Characterization of acetophenone glycosides and condensed tannins.
- Gel permeation chromatography for molecular mass determination.
- DPPH radical scavenging assay to evaluate antioxidant activity.
Main Results:
- Two new acetophenone glycosides and four known compounds were identified.
- Four high-molecular-mass condensed tannin fractions (B-type procyanidin) were detected with average molecular masses between 15,000-113,000 Da.
- All isolated condensed tannin fractions exhibited significant 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity.
Conclusions:
- Hazelnut kernels are a rich source of diverse phenolic compounds, including novel glycosides and tannins.
- The high-molecular-mass condensed tannins from hazelnuts possess notable antioxidant properties.
- These findings support the potential of hazelnuts as a functional food ingredient for health promotion.
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