4味归肺经中药的黄酮成分簇“印迹模板”特征分析及其体外归经研究方法建立

Characteristic Analysis of Imprinting Template of Flavonoid Clusters in Four Chinese Medicines to Lung Meridian and Establishment ofExperimental Approach of Meridian Tropism in Vitro

目的:对归肺经4味中药黄酮成分簇的“印迹模板”特征进行研究,建立中药体外归肺经的研究方法。方法:以普通高等教育“十三五”国家级规划教材《中药学》中只归肺经的苍耳子、鱼腥草、金荞麦、射干等13味中药为基础,确定鱼腥草、金荞麦、射干、桑白皮4味代表中药,通过高效液相色谱法(HPLC)建立指纹图谱,并计算4味中药中所含各类成分的分子连接性指数,运用夹角余弦法计算其与平均分子连接性指数的相似性,以此建立构印定量关系,确定各成分归肺经次序。选择绿原酸、芦丁、槲皮苷、异槲皮苷、金丝桃苷、表儿茶素、野鸢尾苷共7种对照品验证模型的黄酮类成分整体的构印关系及其预测能力。结果:鱼腥草、金荞麦、射干和桑白皮共含有437种化学成分,其平均分子连接性指数相似度为0.9956,4味中药共含黄酮类成分204个,平均分子连接性指数相似度为0.9780,仅次于生物碱的0.9851。7个对照品的保留时间(t_(R))与分子连接性指数相似度(S)呈良好构印关系(t_(R)=831.4×S-790.3,r=0.8614,P<0.01),适用于98.04%黄酮类成分簇的位次、相似度、相对相似度与tR的体外归经研究。据此可得第1位为桑黄酮D,分子连接性指数相似度为0.9877,t_(R)为30.88 min;第200位为绿原酸,分子连接性指数相似度为0.9582,tR为6.36 min;按指纹图谱的总量统计矩法算得的4味中药的总量一阶矩为24.26 min,列位21,能表征整体的99.19%,7种对照品的药材峰面积总量一阶矩为20.00 min,列位46,能表征整体的98.68%。结论:黄酮类成分簇是研究归肺经的“印迹模板”特征的适宜探针,据此能建立起定量结构信息与tR关系的体外中药归经研究方法。

Objective:To study the characteristics of imprinting template of flavonoid clusters in four Chinese medicines attributed to the lung meridian,and to establish an in vitro experimental approach for the study of the attribution of Chinese medicines to the lung meridian.M ethod:Based on 13 Chinese medicines,including Xanthii Fructus,Houttuyniae Herba,Fagopyri Dibotryis Rhizoma,Belamcandae Rhizoma and so on,which only belong to the lung meridian in Chinese Materia Medica(the 13^(th) Five-Year planning textbook of general higher education),we identified four representative Chinese medicines,namely Houttuyniae Herba,Fagopyri Dibotryis Rhizoma,Belamcandae Rhizoma and Mori Cortex,and set up their fingerprints by high performance liquid chromatography(HPLC)and calculated the molecular connectivity indices of various components in the four Chinese medicines,the similarity to their mean value was calculated by included angle cosine method,so as to establish the quantitative relationship of construction versus imprinting ability,and to determine the order of each component in the lung meridian.A total of 7 reference substances,including chlorogenic acid,rutin,quercetin,isoquercitrin,hyperoside,epicatechin,and iridin,were selected to validate the overall conformational relationships of flavonoids of the model,as well as its predictive ability.Result:Houttuyniae Herba,Fagopyri Dibotryis Rhizoma,Belamcandae Rhizoma and Mori Cortex contained a total of 437 chemical components with an average molecular connectivity index similarity of 0.9956.The four Chinese medicines contained a total of 204 flavonoids with an average molecular connectivity index similarity of 0.9780,which was second only to the alkaloids with 0.9851.The retention time(t_(R))of the 7 reference substances showed a good conformational relationship with the similarity of the molecular connectivity index(t_(R)=831.4×S-790.3,r=0.8614,P<0.01),which was applicable to the in vitro attribution study of the position,similarity,and relative similarity with t_(R) of the cluster of 98.04%of flavonoids.Accordingly,the 1st position was kuwanon D,with a similarity of molecular connectivity index of 0.9877 and a t_(R) of 30.88 min,the 200^(th) position was chlorogenic acid,with a similarity of molecular connectivity index of 0.9582 and a t_(R) of 6.36 min.The total first-order moment of the four Chinese medicines calculated by total statistical moment method of fingerprint was 24.26 min,ranked 21,which could characterize 99.19%of the whole,and the total first-order moment of the total peak area of the 7 reference substances in the four Chinese medicines was 20.00 min,with a rank of 46,which could characterize 98.68%of the whole.Conclusion:Flavonoid clusters are suitable probes for the characterization of imprinting template for the study of the lung meridian,which can be established a quantitative imprinting method for meridian tropism of Chinese medicines in vitro.