Extraction and optimization of flavonoids from Elaeagnus pungens Thunb and its potential impact on blood plasma cholesterol in a mouse model

Elaeagnus pungens Thunb is a significant source of flavonoids with biological function. This study aims to develop orthogonal tests and alkali alcohol extraction methods for extracting flavonoids from leaves of E. pungens. The levels of factors in the orthogonal test were determined by pre-experiment, and the physiological efficacy was verified by the in vivo test. The results indicated that the optimal extraction yield was 4.07% when the solid-to-liquid ratio was 1:40, the concentration of ethanol was 60%, the extraction temperature was 80℃, and the extraction time was five h. The alkalialcohol extraction results demonstrated that the extraction yield of flavonoids could be significantly enhanced by different concentrations of alkali-alcohol solution. When the concentration of the alcohol solution was 0.01 mol/L of sodium hydroxide, the extraction efficiency could be increased by 3 times compared with that of the alcohol extraction method. Furthermore, in vivo physiological studies have demonstrated that flavonoid extract from E. pungens had a significant role in reducing the total cholesterol in blood plasma. The findings offer a theoretical and experimental foundation for future research and application of flavonoids derived from E. pungens.