核桃花中绿原酸、新绿原酸和隐绿原酸的提取工艺优化及其抗氧化活性研究

Optimization of extraction technology and antioxidant activity of chlorogenic acid, neochlorogenic acid and cryptochlorogenic acid from walnut flowers

中文关键词:  核桃花  绿原酸  新绿原酸；隐绿原酸；抗氧化  提取工艺  响应面法

英文关键词:walnut flowers  chlorogenic acid  neochlorogenic acid  cryptochlorogenic acid  antioxidant activity  extraction process  response surface method

中文摘要:

      目的 探讨干燥核桃花中绿原酸、隐绿原酸和新绿原酸的最佳提取工艺及其抗氧化活性。方法 采用超声波辅助乙醇法提取核桃花中的绿原酸、新绿原酸和隐绿原酸, 以提取温度、乙醇体积分数、提取时间和料液比为自变量, 以得率的总评归一值(overall desirability, OD)为因变量, 应用响应面对提取工艺进行优化, 并通过体外实验评价了其抗氧化活性。结果 最佳提取工艺为: 温度77℃、乙醇体积分数67%、提取时间28 min, 料液比1:23 (g/mL)。此时, 绿原酸、新绿原酸和隐绿原酸的总提取率最佳, OD值可达0.91, 对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基、2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt, ABTS]阳离子自由基和羟自由基的半数抑制浓度(half-maximal Inhibitory concentrations, IC50)值分别为41.63、41.68和34.43 μg/mL。结论 优选出的工艺稳定可行, 且提取液具有较好的体外抗氧化活性, 为核桃花中绿原酸类成分的进一步开发利用提供了理论基础。

英文摘要:

      Objective To investigate the optimal extraction process and antioxidant activity of chlorogenic acid, neochlorogenic acid and cryptochlorogenic acid in dried walnut flowers. Methods Ultrasonic-assisted ethanol method method was used to extract chlorogenic acid, neochlorogenic acid and cryptochlorogenic acid from wulnut flowers. The independent variables included extraction temperature, ethanol volume fraction, extraction time, and material-liquid ratio, while the dependent variable was the overall desirability (OD) of the yield. The extraction process was optimized using Box-Behnken response surface methodology, and antioxidant activity was assessed through in vitro experiments. Results The best extraction conditions were as follows: Temperature of 77℃, ethanol volume fraction of 67%, extraction time of 28 minutes, and material-liquid ratio of 1:23 (g/mL). Under these conditions, the concentrations of chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid were maximized, resulting in an OD value of 0.91. The half-maximal inhibitory concentrations (IC50) for 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt (ABTS) positive ion free radicals, and hydroxyl free radicals were found to be 41.63, 41.68 and 34.43 μg/mL, respectively. Conclusion The optimized process is stable and feasible, and the extract has good antioxidant activity in vitro, which provides a theoretical basis for the further development and utilization of chlorogenic acids in walnut flower.