杨梅根药材质量标准研究

Quality Standard of Myricae Radix

目的建立杨梅根药材的质量标准。方法观察杨梅根药材样品性状,并对其粉末进行显微鉴别和薄层色谱鉴别;按2020年版《中国药典(四部)》通则项下方法测定样品中的水分、总灰分、酸不溶性灰分和醇溶性浸出物;采用高效液相色谱法测定样品中杨梅苷的含量,色谱柱为Symmetry®C8柱(250 mm×4.6 mm,5μm),流动相为乙腈-0.1%磷酸水溶液(13∶87,V/V),流速为1.0 mL/min,检测波长为260 nm,柱温为40℃,进样量为5μL。结果杨梅根药材性状符合规定。显微鉴别结果显示,样品粉末呈灰棕色,显微镜下可见木栓细胞、韧皮纤维、木纤维、石细胞、草酸钙方晶、导管。薄层色谱图中特征斑点显色清晰,分离度好。16批样品的水分为2.8%~10.4%,总灰分为0.7%~1.2%,酸不溶性灰分为0.1%~0.2%,60%乙醇浸出物为15.7%~28.5%。杨梅苷的质量浓度在0.01~0.25 mg/mL范围内与峰面积线性关系良好(r=1.0000,n=7);检测限为0.0021 mg/mL,定量限为0.0070 mg/mL;精密度、稳定性、重复性试验结果的RSD均低于2.0%;平均加样回收率为101.67%,RSD为1.30%(n=6)。16批样品中杨梅苷含量为0.62%~3.43%,平均1.96%。结论所建立的方法可用于杨梅根药材的质量控制。初步拟订杨梅根药材质量标准为,水分不得过10.0%,总灰分不得过5.0%,酸不溶性灰分不得过2.0%,醇溶性浸出物不得少于15.0%,杨梅苷含量按干燥品计算不得少于1.5%。

Objective To establish a quality standard of Myricae Radix.Methods The characteristics of the Myricae Radix were observed,and the microscopic identification and thin-layer chromatography(TLC)identification of its powder were conducted.The water content,total ash content,acid-insoluble ash content,and alcohol-soluble extract content in the sample were determined according to the general rules of the Chinese Pharmacopoeia(2020 Edition,VolumeⅣ).High-performance liquid chromatography(HPLC)method was adopted for the content determination of myricetin in the sample,the chromatographic column was Symmetry®C8 column(250 mm×4.6 mm,5μm),the mobile phase was acetonitrile-0.1%phosphoric acid aqueous solution(13∶87,V/V),the flow rate was 1.0 mL/min,the detection wavelength was 260 nm,the column temperature was 40℃,and the injection volume was 5μL.Results The medicinal properties of Myricae Radix could meet the requirements.The microscopic identification results showed that the sample powder was grayish brown,and cork cells,phloem fibers,wood fibers,stone cells,calcium oxalate crystals,and vessels could be found under the microscope.The characteristic spots in the TLC chromatograms were clearly colored with good separation.The water content of 16 batches of samples was in the range of 2.8%-10.4%,the total ash content was in the range of 0.7%-1.2%,the acid-insoluble ash content was in the range of 0.1%-0.2%,and the 60%ethanol extract content was in the range of 15.7%-28.5%.The linear range of myricetin was 0.01-0.25 mg/mL(r=1.0000,n=7).The limit of detection(LOD)was 0.0021 mg/mL,and the limit of quantitation(LOQ)was 0.0070 mg/mL.The RSDs of precision,stability,and repeatability tests were all lower than 2.0%.The average recovery of myricetin was 101.67%with an RSD of 1.30%(n=6).The content of myricetin in 16 batches of samples was in the range of 0.62%-3.43%,with an average of 1.96%.Conclusion The established method can be used for quality control of Myricae Radix.The preliminary quality standard of Myricae Radix are as follows:the water content should not higher than 10.0%,the total ash content should not higher than 5.0%,the acid-insoluble ash content should not higher than 2.0%,the alcohol-soluble extract should not be lower than 15.0%,and the myricetin content should not be lower than 1.5%calculated based on dried products.