Enrichment of total polyphenols from Elaeagnus angustifolia L.leaves by macroporous resin and study on their antioxidant activity

SU Weihang; WANG Zhong; SUN Yun

doi:10.13557/j.cnki.issn1002-2813.2026.01.019

Abstract：This study aimed to optimize and scale up the purification process of total polyphenols from Elaeagnus angustifolia L.leaves(TPEAL),compare the in vitro antioxidant activity of the products before and after purification,and evaluate the in vivo antioxidant activity of the purified total polyphenols from Elaeagnus angustifolia L.leaves(TPPEAL).The optimal purification process for TPEAL was determined through static and dynamic adsorption-desorption experiments,followed by process scale up.The scavenging capacity against 2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical was measured for the products before and after purification.By establishing an ethanol induced oxidative damage model in mice and administering TPPEAL by intragastric administration,relevant indicators were detected to evaluate its in vivo antioxidant activity.The results showed that the optimal process conditions using AB-8 macroporous resin were as follows:Sample solution at pH value of 2,sample volume of 4 BV,sample concentration of 1 600 mg/L(calculated based on total polyphenol content),and flow rate of 1.0 mL/min.Elution was performed with 70％ethanol solution,elution volume of 8 BV,flow rate of 1.0 mL/min.Under these conditions,the total polyphenol content of TPPEAL reached 52.96％,which was 3.75 times higher than that of the crude extract of total polyphenols from Elaeagnus angustifolia L.leaves(CETPEAL).Scale up experiments demonstrated that the total polyphenol content in TPPEAL did not significantly decrease with increased resin loading,indicating good process stability.In vitro antioxidant tests showed that the DPPH free radical scavenging rate of 0.5 g/L TPPEAL was 90.52％,1.19 times that of CETPEAL.In vivo experiments revealed that TPPEAL could effectively reverse ethanol induced oxidative damage,extremely increased liver index,serum glutathione peroxidase(GSH-Px)and total superoxide dismutase(T-SOD)activities,and total antioxidant capacity(T-AOC)in model mice(P＜0.01),and extremely reduced serum malondialdehyde(MDA)content(P＜0.01).The study shows that the established purification process for TPEAL and its scaled up version are stable and feasible,and the purified product exhibits good antioxidant activity both in vitro and in vivo.