Folin-Ciocalteu比色法测定石榴皮多酚含量条件的优化研究

Optimization study on conditions for the measurement of polyphenol content in Pomegranate Peel by Folin-Ciocalteu colorimetry

目的筛选确定Folin-Ciocalteu比色法测定石榴皮提取物中多酚含量的最佳条件。方法本研究选用没食子酸为标准物质,确定测定波长后系统考察多酚含量测定过程中Folin-Ciocalteu试剂(FC试剂)浓度、Na2CO3试剂浓度、反应时间、反应温度等多因素的影响,并对方法学进行考察。结果研究表明,采用Folin-Ciocalteu比色法测定石榴皮提取物多酚含量,取样品液1 ml、40%FC试剂用量5 ml、10%Na2CO3试剂用量4 ml、在20℃避光反应100 min为最佳反应条件,多酚含量与750 nm处吸光度呈良好线性关系;本法加标平均回收率为99.51%,RSD为2.56%。利用优化后的方法测定石榴皮样品中多酚含量为(142.42±5.88)mg/g。结论优化后的Folin-Ciocalteu比色法方便稳定,是检测石榴皮中多酚含量的可靠方法。

Objective To screen and determine the optimal conditions for measurement of polyphenol content in Pomegranate Peel extracts by Folin-Ciocalteu colorimetry.Methods In this study,Gallic Acid was selected as the standard substance.After determining the wavelength of measurement,the effects of Folin-Ciocalteu(FC)reagent concentration,Na2CO3 reagent concentration,reaction time and reaction temperature were investigated systematically,and the methodology was also investigated.Results It was showed that the optimum conditions for the measurement of polyphenols in Pomegranate Peel extracts were:1 ml sample solution,5 ml 40%FC reagent,4 ml 10%Na2CO3 reagent and protected from light at 20℃for 100 min.The polyphenol content had a good linear relationship with the absorbance at 750 nm.The average recovery rate of this method was 99.51%,and the RSD was 2.56%.The polyphenol content in the Pomegranate leaf sample was determined to be(142.42±5.88)mg/g by the optimized method.Conclusion The optimized folin-ciocalteu colorimetric method is convenient and stable,and is reliable to measure polyphenol content in Pomegranate Peel extracts.