A REVIEW OF RESEARCH ON BIOLOGICAL ACTIVITIES OF QUERCETIN

Abstract

Quercetin is a naturally occurring flavonoid widely distributed in many plant species and is known for its many important biological activities. This article summarizes and analyzes published studies on the biological activity of quercetin, focusing on its antioxidant, anti-inflammatory, antibacterial, anticancer, and cardioprotective effects. Experimental evidence shows that quercetin can regulate oxidative stress, inhibit inflammatory responses by modulating related cytokines and enzymes, and help protect cells from damage caused by free radicals. In addition, the article outlines common quercetin extraction methods, including solvent extraction, ultrasonic extraction, and green solvent technology, to improve the compound's efficiency and purity. Although quercetin is considered to have potential applications in supporting the treatment of chronic diseases such as diabetes, cardiovascular disease, and cancer, limitations in bioavailability and stability still necessitate further research to optimize practical applications.