Stability of an Antioxidant from Plants in Various Conditions

Abstract

Quercetin, an effective antioxidation agent, could be found in vegetables, fruits, and flowers, and tea. Several healthcare products containing quercetin had been developed for use as disease prevention and/or food supplements. Owing to its signigicance, quercetin is chosen for this study as a representative to an antioxidation of flavonoids grop. The data provide information factors causing degradation and stabilization of quercetin which will be important in the development of its derived healthcare products. These influent factors included types and pH of solvent, temperature, an interference of metal, and vitamin C, which is popularly used in various healthcare products. The stability of quercetin was analyzed by measuring quercetin content using UV spectrophotometer at 373 nm within 5 days of storage time. The results showed that quercetin in organic solvent were higher stable than in aqueous system which it found about 50% after 2 days of storage time. Refrigerator accelerated the degradation of quercetin in aqueous system. Temperature under refrigeration could prolong its stability, while basic condition and the metal contamination. Therefore, all above conditions has to be controlled throughout the steps of preparation and processing to storage in order to keep the quality and antioxidant activity of quercetin in healthcare products.