肉桂枝叶非挥发部分原花青素含量测定的比较研究

Comparative Study on Determination of Procyanidins Content in Branches and Leaves of Cinnamon cassia

目的：对肉桂枝叶非挥发部分的原花青素含量进行测定，并考察香草醛法扣铁盐催化法两种测定方法的优劣。方法：以儿茶素为对照品，甲醇为溶剂，采用香草醛-盐酸法测定原花青素含量。以原花青素为对照品，正丁醇为介质，采用铁盐催化法测定原花青素含量。结果：香草醛法中样品在儿茶素吸收度较高区间490-510nm处没有明显吸收峰，铁盐催化法中样品在原花青素最大吸收波长550nm处有最大吸收。对照品原花青素在0．05～0．30mg／mL范围内与吸光度呈良好的线性关系，回归方程为y=4．242x-0．1275（R^2=0．9993），精密度RSD=0．06％，重复性RSD=0．759，6，稳定性RSD=0．79％，回收率RSD=1．24％。结论：铁盐催化法比较适合肉桂枝叶非挥发成分原花青素含量的测定，且具有良好的精密度、重复性、稳定性，回收率也较高；而香草醛法则不理想。

Objective： To investigate and compare the advantages and disadvantages of vanillin method and molysite catalytic method, the procyanidins content in branches and leaves of Cinnamon cassia is determined. Methods. Firstly, catechin is as the reference substance, methanol is as the solvent, the vanillin-hydrochloric acid method is used for determination of procyanidins content, and then procyanidins is as the reference substance, n-butyl alcohol is as the reaction medium, molysite catalytic method is used for determination of procyanidins content. Results. For vanillin method, the cinnamon sample has no apparent absorption peak as the absorbance of catechin in the range of 490- 510 nm. However, for molysite catalytic method, the cinnamon sample has the maximum absorption as the maximum absorption wavelength of procyanidins is at 550 nm. The procyanidins reference substance has a good linear relationship with the absorbance within the range of 0.05-0.30 mg/mL, the regression equation is y = 4. 242x- 0. 1275 （R2 = 0. 9993）, the precision RSD = 0. 06%, the repeatability RSD=0.75%, the stability RSD=0.79%, the recovery RSD= 1.24%. Conclusion. The molysite catalytic method should be more suitable for the determination of procyanidins content fromthe branches and leaves of Cinnamon cassia, and it has good precision, repeatability, stability and higher recovery rate,