Effect of Different Solvents on the Antioxidant Activity and Polyphenol Stability of Loquat (Eriobotrya japonica Lindl.) Fruit Extract

Abstract:

Loquat (Eriobortya japonica Lindl.) is a health-promoting fruit native to China, rich in nutrients and with high medicinal value. The author investigated the effects of different solvents on the antioxidant activity and polyphenol mass fraction of loquat fruit extracts, analyzed the correlation between the two, and explored the effects of temperature, pH, metal ions, and food additives on the stability of loquat polyphenols. The results showed that the extraction efficiency was highest with 20% ethanol by volume. A strong correlation was observed between the antioxidant activity and polyphenol mass fraction of the various solvent extracts from loquat fruit, with ethyl acetate extracts exhibiting the most prominent antioxidant activity and polyphenol mass fraction. High temperature reduced the stability of loquat polyphenols, with pH 6 showing the least impact on their stability. Metal ions such as Na⁺, Ca²⁺, Fe²⁺, Na₂SO₃, and food additives all contributed to a decrease in loquat polyphenol stability. This study provides a basis for the extraction of loquat polyphenols and offers a reference for further research on polyphenol stability, as well as expanding the applications of loquat fruit.