Abstract:To study the separation and purification of polyphenols from Myrciaria cauliflora leaves, four resins, such as NKA-2, NKA-9, HPD-826 and HPD-400A, were screened, and the antioxidant, in vitro hypoglycemic activities and components of polyphenols were analyzed. The results showed that NKA-9 resin was suitable for the purification of polyphenols from the leaves. The optimum conditions were as follows:sample concentration of 2.00 mg/mL, flow rate at 1.0 mg/mL and sample loading of 204 mL, 70 mL 70% (V/V) ethanol as elution with velocity at 0.9 mL/min. Under the conditions, the purity of polyphenols from the leaves could reach 69.86%. The antioxidant and α-glucosidase inhibitory activities of purified polyphenols from leaves of M. cauliflora were stronger than those of crude polyphenols, but the inhibitory activities on α-amylase were lower. According to HPLC, the monophenols in leaves of M. cauliflora contained myricetin, rutin, hyperoside and ellagic acid, and ellagic acid content was highest with (16.15±0.49) mg/g. Therefore, NKA-9 resin was suitable for separation and purification of polyphenols from leaves of M. cauliflora, the antioxidant and α-glucosidase inhibitory activities of purified polyphenols increased.
