目的：建立青龙衣水解单宁含量测定的方法。方法以没食子酸为对照品，研究青龙衣水解单宁的含量测定，采用紫外‐可见分光光度法，确定改良的Folin‐Ciocalteu法运用于青龙衣单宁含量测定显色的最佳条件，测定青龙衣酸解前后总单宁的含量。结果测定没食子酸的标准曲线方程为：Y＝151．8 X＋0．041，在0．992～4．960μg · m L －1范围内线性关系良好，r＝0．999（n＝6）。优化的显色方法为1．0 mL的样品液，Folin‐Ciocalteu 1．5 mL ，加去离子水10 mL ，用70 g · L －1的碳酸钠定容至25 mL，30℃显色1．5h。结论该显色方法操作简便，准确度高、稳定性和重复性良好，既适用于未酸解单宁样品的含量测定，也适用于酸解后单宁样品的含量测定，对水解单宁类成分的含量测定具有普遍适用性。%Objective To establish a method for the determination of the hydrolyzed tannins from Juglans regia L ..Methods Gallic acid as a reference compound .UVspectrophotometry was used for the determination of the hydrolyzed tannins from Juglans regia L ..The modified Folin‐Ciocalteu method was set up ,then it was used to determine the contents of both the un‐hydrolyzed tannins and the hydrolyzed tannins .Results The standard curve equation was :Y=151 .8X+0 .041 ,and gallic acid was linear in the range of 0 .992‐4 .960 μg · mL -1 ,r=0 .999(n=6) .The optimal conditions for determining the hydrolyzed tannins from Juglans regia L .were as followed :1 .0 mL of the sample ,1 .5 mL of F‐C reagent ,10 mL of water ,with 70 g · L -1 sodium carbonate solution to the volume ,treatment at 30 ℃ for 1 .5 h .Conclusion This method is simple ,accurate ,stable and repeatable .It has universal applicability for the determination of both the un‐hydrolyzed tannins and the hydrolyzed tannins .
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