嘉宝果嫩叶提取物不同极性部位抗氧化及抑制α-葡萄糖苷酶活性研究

从植物中寻找天然的抗氧化剂和α-葡萄糖苷酶抑制剂对糖尿病患者具有重要的意义。采用比色法对嘉宝果嫩叶醇提物不同极性部位进行总多酚和总黄酮含量、抗氧化活性及α-葡萄糖苷酶活性抑制活性研究,以期为嘉宝果嫩叶有效提取部位在食品、化工及医学领域的应用提供一定的参考依据。结果表明,乙酸乙酯相的总多酚含量（33.92 mg/g及总黄酮含量（13.35 mg/g）最高,其次为正丁醇相（总多酚31.11 mg/g;总黄酮12.93 mg/g）及水相（总多酚17.04 mg/g;总黄酮11.18 mg/g）;石油醚相及二氯甲烷相均未检测到总多酚及总黄酮。乙酸乙酯相与正丁醇相对DPPH及ABTS ⁺自由基的清除能力相当,明显高于其他极性部位。对酵母源和小鼠小肠源α-葡萄糖苷酶活性抑制活性大小依次分别为乙酸乙酯相>正丁醇相>水相>石油醚相>二氯甲烷相和乙酸乙酯相>正丁醇相>水相>二氯甲烷相>石油醚相。以上结果表明嘉宝果嫩叶乙酸乙酯相与正丁醇相总多酚及总黄酮含量较高,抗氧化活性及对α-葡萄糖苷酶活性的抑制作用较强,是挖掘抗氧化及抑制α-葡萄糖苷酶活性物质的主要极性部位。

Antioxidant and α-Glucosidase Inhibitory Activities of Different Polarity Fractions of the Extracts of the Young Leaves of Myrciaria cauliflora

It is of great significance to search for natural antioxidants and α-glucosidase inhibitors from plants to diabetic patients. Based on the previous research, the polarity fractions of the ethanol extracts from the tender leaves of M. cauliflora were applied to determine the scavenging effects towards DPPH and ABTS ⁺ free radicals, inhibition on α-glucosidase activity, the contents of total polyphenols (TP) and total flavonoids (TF) by colorimetry, providing a reference evidence for the application of effective polarity fraction from the tender leaves of M. cauliflora in food, chemical and medical fields. The ethyl acetate fraction exhibited the highest contents of TP (33.92 mg/g) and TF (13.35 mg/g), followed by n-butanol fraction (TP 31.11 mg/g; TF 12.93 mg/g) and water fraction (TP 17.04 mg/g; TF 11.18 mg/g). TP and TF were not detected in the petroleum ether and dichloromethane fractions. The scavenging abilities of n-butanol fraction and ethyl acetate fraction towards DPPH and ABTS ⁺ radicals were higher than that of other fractions. The ethyl acetate fraction had the strongest inhibitory activity in the α-glucosidase, followed by the n-butanol and water fraction. This results indicated that the contents of TP and TF were higher in the ethyl acetate and n-butanol fractions, and the antioxidant activity and inhibition in α-glucosidase activity were stronger, compared with the other three polarity fractions, so the ethyl acetate and n-butanol fractions could be used as the main polar fractions to excavate active substances for antioxidation activity and inhibition activity in α-glucosidase.