桑葚、甘蔗糖蜜多酚的成分鉴定及其复配物的抗氧化活性

为探索酚类提取物及其复配物的协同增效作用，以桑葚和甘蔗糖蜜多酚作为研究对象，分别测定其总酚、黄酮含量及酚类组成，基于单一提取物的总酚含量按一定配比制得复配物，评价抗氧化活性。结果表明，桑葚游离多酚（MFP）占桑葚总酚含量的90.3%，为677.62 mg没食子酸当量（Gallic Acid Equivalent，GAE）/100 g，黄酮含量为736.65 mg芦丁当量（Rutinum Equivalent，RE）/100 g，共检测出原儿茶酸、3,4-二羟基苯丙酸、咖啡酸、丁香酸、对香豆酸、阿魏酸、矢车菊素3-O-葡萄糖苷和芦丁8种多酚物质，其中矢车菊素3-O-葡萄糖苷含量占92.6%。甘蔗糖蜜多酚（SMP）总酚含量为339.69 mg GAE/100 g，总黄酮含量为314.61 mg RE/100 g，主要单体包括没食子酸、原儿茶酸、绿原酸、咖啡酸、丁香酸、对香豆酸、阿魏酸、芦丁和表儿茶素9种多酚物质。在0~10 mg/mL的浓度范围内SMP、MFP及其复配物具有良好的抗氧化活性且呈现量效关系。同时，两种复配物的抗氧化活性优于SMP和MFP，其中中效原理计算复配物DPPH自由基清除能力的0.25 IC50、0.5 IC50、0.75 IC50、1 IC50、1.25 IC50、1.5 IC50的联合作用指数CI分别为0.73、0.85、0.94、0.91、0.89和0.90，均小于1，表明桑葚和甘蔗糖蜜多酚复配物具有协同抗氧化作用。

Composition Analysis of Mulberry Polyphenols and Sugarcane Molasses Polyphenols and the Antioxidant Activity of Their Mixture

To investigate the synergism of polyphenol extracts and their mixtures, the total phenolic content, total flavonoid content, and phenol composition of mulberry and sugarcane molasses polyphenols were determined. Additionally, the antioxidant activity of their mixture, which was formulated based on the total phenolic content of each extract, was assessed. Mulberry free polyphenols (MFP) were found to account for 90.3% of the total phenolic content of mulberry molasses (at 677.62 mg gallic acid equivalent (GAE)/100 g), and their total flavonoid content was 736.65 mg rutin equivalent (RE)/100 g. Eight polyphenols were detected, including protocatechuic acid, 3,4-dihydroxyphenylpropionic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, cyanidin 3-glucoside, and rutin. Cyanidin 3-glucoside accounted for 92.6% of the total phenolic content. Sugarcane molasses polyphenols (SMP) had a total phenolic content of 339.69 mg GAE/100 g and total flavonoid content of 314.61 mg RE/100 g. Their polyphenol monomers included gallic acid, protocatechuic acid, chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, rutin, and epicatechin. At concentrations of 0~10 mg/mL, SMP, MFP, and their mixtures showed excellent antioxidant activities, with clear dose-response relationships. Further, the SMP+MFP mixture had higher antioxidant activities than either SMP or MFP alone. Furthermore, the combination index (CI) values calculated using the median-effect principle for 0.25, 0.5, 0.75, 1, 1.25, and 1.5 of the IC50 concentrations (for DPPH radical scavenging activity) of the mixture were 0.73, 0.85, 0.94, 0.91, 0.89, and 0.90, respectively. Notably, all CI values were less than 1; therefore, SMP+MFP mixtures exhibited synergism in antioxidant activity.