Xây dựng phương pháp định lượng và đánh giá hàm lượng flavonoid toàn phần trong lá cây Đơn lá đỏ (Folium Excoecariae)

Abstract

the leaves of Excoecaria cochinchinensis (Folium Excoecariae) at different time points using UV-VIS spectroscopy.

Subjects and methods: The total flavonoid content was quantified as kaempferol using the UV-Vis spectrophotometric method based on the ultraviolet light absorption capability of kaempferol, the method was validated according to the AOAC 2019 guidelines and applied to evaluate the total flavonoid content in the leaves of Excoecaria cochinchinensis collected at different time points.

Results: The kaempferol content in the leaves of Excoecaria cochinchinensis ranged from 0,3527% to 0,7218%. The method demonstrated high specificity and good linearity in the concentration range of 0,65 to 6,5 µg/mL. Repeatability met the required standard with an RSD of 2,2554%, and recovery ranged from 95% to 105%. Analysis of samples collected at different time points showed that the flavonoid content in the leaves of 3-year-old plants was 0,2422% to 0,2898% higher than that in 1-year-old plants. The highest flavonoid content was recorded in May and the lowest in August within a one-year cycle.

Conclusion: A UV-Vis spectrophotometric method for the quantification of total flavonoid content was successfully developed and validated. The validated method met the required criteria for specificity, linearity (R² = 0,999), repeatability (RSD = 2,2554%), and accuracy (recovery ranged from 95% to 105%). The highest flavonoid content was observed in the leaves of 3-year-old plants collected in May.