亚麻籽水溶蛋白与姜黄素复合物的制备与表征

Preparation and characterization of the compound of water-soluble flaxseed protein-curcumin

以分级提取的亚麻籽水溶蛋白(water-soluble flaxseed protein,FPW)和姜黄素(curcumin,Cur)为原料,制备FPW与Cur的复合物(FPW-Cur),测得每mg FPW可负载0.778μg Cur,复合物溶解后姜黄素溶解度达到36200μg/L,相较于Cur在水溶液中的溶解度(11μg/L)提高了约3291倍。考察了FPW、Cur和FPW-Cur对DPPH、ABTS^(+)·和·O-_(2)自由基清除能力,结果表明复合物的抗氧化活性能力高于单独的FPW和单独的Cur,但低于二者抗氧化活性之和。对FPW红外光谱进行二阶导数分析,结果表明FPW-Cur的α-螺旋、β-折叠和β-转角较FPW分别从15.84%增加到17.46%、从20.47%增加到30.62%和从32.02%增加到36.30%。紫外-可见光谱表征分析表明FPW-Cur位于208 nm附近的吸收峰强度逐渐降低,并发生明显红移,证明FPW与Cur之间存在相互作用。该研究为蛋白质基脂溶性功能分子的载运提供新方法,也为提高亚麻籽蛋白及其水溶蛋白的开发应用价值开辟新途径。

The compound of FPW and Cur was prepared with water-soluble flaxseed protein(FPW)and curcumin(Cur),with a loading capacity of 0.778μg of Cur per mg of FPW.The solubility of Cur measured after the dissolution of FPW-Cur compound in water was 36200μg/L,which was 3291 times more than that of Cur alone dissolved in water(11μg/L).The scavenging capacities of FPW,Cur and FPW-Cur compound against DPPH,ABTS·+and·O2-radicals were evaluated.The results showed that the antioxidant potential of FPW-Cur compound was higher than that of FPW or Cur alone,but lower than the sum of the activities of FPW and Cur.Second derivative analysis of the FTIR spectrum of FPW revealed an increase inα-helix,β-sheet,andβ-turn content in FPW-Cur from 15.84%to 17.46%,20.47%to 30.62%,and 32.02%to 36.30%,respectively,comparing with FPW.UV-vis spectral analysis indicated a gradual decrease in absorption peak intensity near 208 nm for FPW-Cur with a significant redshift,confirming the interaction between FPW and Cur.This study provides a new method for the delivery of protein-based lipophilic functional molecules,and also opens up a new path for improving the development and application value of flaxseed proteins and their water-soluble fractions.