Extraction and Purification of Quercitrin, Hyperoside, Rutin, and Afzelin from Zanthoxylum Bungeanum Maxim Leaves Using an Aqueous Two Phase System.
In this study, an aqueous two phase system (ATPS) based on ethanol/NaH2 PO4 was developed for the extraction and purification of quercitrin, hyperoside, rutin, and afzelin from Zanthoxylum bungeanum Maxim leaves. These 4 flavonoids were 1st extracted from dried Z. bungeanum leaves using a 60% ethanol solution and subsequently added to the ATPS for further purification. The partition behavior of the 4 flavonoids in ATPS was investigated. The optimal ATPS conditions were: 29% (w/w) NaH2 PO4 25% (w/w) ethanol concentration, 1% (w/w) added amount of leaf extracts, no pH adjustment, and repeated 1 h extractions at 25 degC. Under the optimal conditions for the 10 g ATPS, the absolute recovery of quercitrin, hyperoside, rutin, and afzelin reached 90.3% 83.5% 92.3% and 89.1% respectively. Compared to the 60% ethanol extracts, the content of quercitrin (44.8 mg/g) hyperoside (65.6 mg/g) rutin (56.4 mg/g) and afzelin (6.84 mg/g) in the extracts increased by 49.9% 38.8% 45.6% and 36.8% respectively. The extracts after ATPS also exhibited stronger antioxidant activities, the 2,2 diphenyl 1 picrylhydrazyl IC50 value (10.5 mg/mL) decreased by 41.8% and the 2,2 azinobis(3 ethylbenzothiazoline 6 sulfonic acid) diammonium salt value (966 mmol Trolox/g) and ferric reducing power value (619 mmol Trolox/g) increased by 29.8% and 53.7% respectively. Furthermore, scale up experiments indicated that a larger scale experiment was feasible for the purification of the 4 flavonoids.
Journal of food science