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Microwave-Assisted Extraction of Phenolic Compounds and Antioxidants for Cosmetic Applications Using Polyol-Based Technology
Published on: August 23, 2024
Antioxidant polyphenols in almond and its coproducts
Subhashinee S K Wijeratne1, Mamdouh M Abou-Zaid, Fereidoon Shahidi
1Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland A1B3X9, Canada.
Journal of Agricultural and Food Chemistry
|January 19, 2006
Summary
Almond byproducts like brown skin and green shell show potent antioxidant activity, effectively preventing LDL cholesterol oxidation and DNA damage. These natural extracts offer significant health benefits due to high phenolic content.
Area of Science:
- Food Science
- Nutraceuticals
- Biochemistry
Background:
- Almonds are a rich source of bioactive compounds with potential health benefits.
- Investigating the antioxidant properties of almond byproducts can lead to valuable nutraceutical applications.
- Understanding the specific components responsible for antioxidant activity is crucial for product development.
Purpose of the Study:
- To evaluate the antioxidant efficacy of defatted almond whole seed, brown skin, and green shell cover extracts.
- To compare the inhibitory effects of these extracts on human low-density lipoprotein (LDL) oxidation and DNA scission.
- To assess the metal ion chelation activities and identify major flavonoid compounds present in the extracts.
Main Methods:
- Extraction of antioxidant compounds from almond parts using ethanol.
- Assessing antioxidant activity through inhibition of LDL oxidation, DNA scission, and metal ion chelation assays.
- Quantifying total phenolic content and identifying major flavonoids using High-Performance Liquid Chromatography (HPLC).
Main Results:
- Almond brown skin and green shell cover extracts exhibited significantly higher total phenolic content compared to whole seed extract.
- Brown skin extract at 50 ppm effectively inhibited copper-induced LDL cholesterol oxidation, outperforming whole seed and green shell extracts.
- Green shell cover extract at 50 ppm completely inhibited DNA scission, while brown skin and whole seed extracts required 100 ppm for similar efficacy.
- All almond extracts demonstrated excellent metal ion chelation properties.
- Major flavonoids identified include quercetin, isorhamnetin, quercitrin, kaempferol 3-O-rutinoside, isorhamnetin 3-O-glucoside, and morin.
Conclusions:
- Almond byproducts, particularly brown skin and green shell cover, possess substantial antioxidant properties.
- These extracts show potential for use as natural antioxidants in food and pharmaceutical applications.
- The identified flavonoids contribute to the observed antioxidant activities, highlighting their nutraceutical value.
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