Abstract: The purification process of hawthorn leaf polyphenols was investigated, and its antioxidant activity and constituents were analyzed. The adsorption properties of selected four macroporous resins (SP-825, D101, AB-8, XDA-2) for hawthorn leaf polyphenols were compared, the optimum purification resins were screened and the purification parameters were optimized. The antioxidant activity, composition and infrared spectroscopic characteristics of hawthorn leaf polyphenols were investigated. The results showed that AB-8 resin possessed the best effect on the purification of hawthorn leaf polyphenols. The optimum purification parameters were as follows, initial sample solution pH 4.5, sample concentration 0.064 mg/mL, sampling flow rate 1.5 mL/min, elution flow rate 0.6 mL/min with 70% ethanol. Under these conditions, the recovery rate was 78.25%, the purity of polyphenol was increased by 4.15 times after purification. The crude extract and purified substance of hawthorn leaf polyphenols showed good antioxidant activity, the IC50 values of DPPH· scavenging capacity were (1.28±0.14) μg/mL and (0.78±0.09) μg/mL respectively, the IC50 values of Fe2+ chelating capacity were (55.58±1.24) μg/mL and (34.13±1.02) μg/mL respectively, the IC50 values of total reduction power were (3.66±0.18) μg/mL and (2.12±0.23) μg/mL respectively, the IC50 values of purified hawthorn leaf polyphenols for ·OH scavenging capacity were (4.49±0.16) μg/mL, which indicated that the antioxidant capacity of the purified substance of hawthorn leaf polyphenols was significantly improved compared with the crude extracts. FTIR analysis showed that the purified hawthorn leaf polyphenols had characteristic peaks of polyphenols and flavonoids, HPLC analysis showed that the purified hawthorn leaf polyphenols mainly contained chlorogenic acid, epicatechin, ferulic acid, rutin and ursolic acid, which indicated that hawthorn leaf polyphenols have good utilization and development prospects.
ELANGO C, DEVARAJ N S. Immunomodulatory effect of Hawthorn extract in an experimental stroke model[J]. Journal of Neuroinflammation, 2010, 7:97.
KOCH E, MALEK F. Standardized extracts from hawthorn leaves and flowers in the treatment of cardiovascular disorders-preclinical and clinical studies[J]. Planta Medica, 2011, 77(11):1 123-1 128.
KWOK C Y, LI C, CHENG H L, et al. Cholesterol lowering and vascular protective effects of ethanolic extract of dried fruit of Crataegus pinnatifida, hawthorn (Shan Zha), in diet-induced hypercholesterolaemic rat model[J]. Journal of Functional Foods, 2013, 5(3):1 326-1 335.
AIERKEN A, BUCHHOLZ T, CHEN C, et al. Hypoglycemic effect of hawthorn in type Ⅱ diabetes mellitus rat model[J]. Journal of the Science of Food and Agriculture, 2017, 97 (13):4 557-4 561.
XI L, MU T, SUN H. Preparative purification of polyphenols from sweet potato (Ipomoea batatas L.) leaves by AB-8 macroporous resins[J]. Food Chemistry, 2015, 172:166-174.
GUO C, QIAO J, ZHANG S, et al. Purification of polyphenols from kiwi fruit peel extracts using macroporous resins and high-performance liquid chromatography analysis[J]. International Journal of Food Science & Technology, 2018,53(6): 1 486-1 493.
WANG G L, BOVSSETTA N, LEBOVKA N, et al. Ultrasound assisted purification of polyphenols of apple skins by adsorption_desorption procedure[J]. Ultrasonics-Sonochemistry, 2019,55:18-24.
CHUPIN L, MOTILLON C, BOUHTOURY C E, et al. Characterisation of maritime pine (Pinus pinaster) bark tannins extracted under different conditions by spectroscopic methods, FTIR and HPLC[J]. Industrial Crops & Products, 2013, 49(7):897-903.