论文部分内容阅读
目的:测定鱼腥草中总多酚的含量,利用响应面分析法(RSM)优化其提取工艺。方法:以乙醇为溶剂从鱼腥草样品中超声提取多酚,以没食子酸为对照品,采用Folin-ciocalteu比色法于最大波长处测定总酚含量,建立多酚含量测定的测定方法。在单因素试验的基础上,采用Box-Benhnken中心组合试验设计和三因素三水平响应面分析法,对物料比、乙醇浓度、提取时间3个影响因素各自变量进行研究。分析各因素的显著性和交互作用,优化鱼腥草总多酚的最佳提取工艺,比较不同产地样品中多酚含量差异。结果:在750 nm波长处回归方程为y=0.100 5x-0.029 7(R~2=0.994 3),加样回收率为99.60%~106.35%(RSD=2.50%)。各因素对鱼腥草总多酚提取的影响程度依次为:乙醇浓度>料液比>提取时间。最佳提取工艺为料液比1∶29.27,乙醇浓度为68.30%,提取时间69.02 min。采自上虞和杭州地区的鱼腥草中总多酚含量分别为15.80 mg·g-1和14.45 mg·g~(-1)。结论:本实验建立的鱼腥草总多酚提取测定方法简便有效,精密度高,稳定性和重复性好,为鱼腥草药用价值评估提供依据。
Objective: To determine the content of total polyphenols in Houttuynia cordata and optimize its extraction process by response surface analysis (RSM). Methods: Polyphenol was extracted from Houttuynia cordata with ethanol as solvent and gallic acid as reference substance. Folin-cocalocal colorimetric method was used to determine the total phenolic content at the maximum wavelength. The determination method of polyphenol content was established. Based on the single factor test, the Box-Benhnken central composite design and the three-factor three-level response surface analysis method were used to study the variables of material ratio, ethanol concentration and extraction time. The significance and interaction of each factor were analyzed. The optimum extraction process of total polyphenols from Houttuynia cordata Thunb. Was optimized. The differences of polyphenol content among different samples were compared. Results: The regression equation was y = 0.100 5x-0.029 7 (R ~ 2 = 0.994 3) at the wavelength of 750 nm. The recoveries were 99.60% -106.35% (RSD = 2.50%). The factors influencing the extraction of total polyphenols from Houttuynia cordata were: ethanol concentration> solid-liquid ratio> extraction time. The optimum extraction process was solid-liquid ratio 1:29.27, ethanol concentration 68.30%, extraction time 69.02 min. The contents of total polyphenols in Houttuynia from Shangyu and Hangzhou were 15.80 mg · g-1 and 14.45 mg · g -1, respectively. Conclusion: The Houttuynia cordata total polyphenols extraction method established in this experiment is simple and effective, high precision, good stability and reproducibility, and provide the basis for the evaluation of medicinal value of Houttuynia cordata.