不同产地和规格等级天麻矿质元素分析与评价

Analysis and Evaluation of Mineral Elements in Gastrodia elata with Different Specifications and Grades from Diverse Producing Areas

目的:研究不同产地和规格(变型)等级天麻中矿质元素的分布特征及分类鉴定依据。方法:采用原子吸收分光光度法、钼锑抗比色法和姜黄比色法对31批次不同产地和规格(变型)等级天麻样品中14种矿质元素进行测定,运用相关性分析、判别分析与主成分分析对测定结果进行系统分析与评价。结果:天麻中K,N,P元素含量高,为影响天麻生长的营养限制因子,K>N>P>Mg>Ca>Fe>B>Zn>Mn>Cu>Ni>Cr>Pb>Cd元素变化趋势可用于鉴别天麻药材;不同产地间比较发现,昭通天麻P,Fe,Cd元素含量最高,丽江天麻K元素含量最高,罗田天麻Zn,Cr元素含量最高,金寨天麻Cu,Pb元素含量最高;不同规格(变型)间比较发现,红天麻中Mg,B,Pb和Cr元素含量高于乌天麻;不同等级间比较发现,P,Cu,Cd元素含量随商品麻等级降低而逐渐升高,Mg,Fe,B,Ni元素含量随商品麻等级降低多呈下降趋势。相关性分析表明,Fe元素与Mg,Cr,B元素均呈正相关。判别分析可有效鉴定天麻不同产地,准确率达85.71%,其中Cd,Pb,Cr,Cu,B和Ni元素为判别函数的重要变量。通过矿质元素主成分分析发现,云南昭通乌天麻样品得分集中,前3个主成分显示,Fe,Cr,Mg,Cd,P,Mn,B,Pb和Cu元素对天麻影响较大。结论:以矿质元素为依据对天麻进行鉴别具有一定可行性,该法快速、准确、稳定性强,可为天麻药材真伪鉴别、产地溯源等提供参考依据。

Objective: To study the distribution characteristics of mineral elements in Gastrodia elata samples with different grades and specifications(variants)from diverse producing areas and their classification and identification evidences. Method: Fourteen mineral elements in 31 batches of Gastrodia elata samples of different grades and specifications(variants) from diverse producing areas were determined by atomic absorption spectrophotometry,Mo-Sb colorimetry,and curcumin colorimetry,and then subjected to correlation analysis(CA),discriminant analysis(DA),and principal component analysis(PCA). Result: The content of K,N,and P in G. elata was the highest,enabling them to serve as the nutritional limiting factors affecting its growth. The G. elata samples could be identified by the variation trend of elements(K>N>P>Mg>Ca>Fe>B>Zn>Mn>Cu>Ni>Cr>Pb>Cd). The comparison of G. elata samples from multiple producing areas showed that G.elata from Zhaotong has the highest P,Fe,and Cd content,that from Lijiang the highest K content,that form Luotian the highest Zn and Cr content,and that from Jinzhai the highest Cu and Pb content. The content of Mg,B,Pb,and Cr in G. elata f. elata was higher than that in G. elata f. glauca. It was found that the content of P,Cu,and Cd in commercially available G. elata products gradually increased with the decrease in the commercial grade,while that of Mg,Fe,B,and Ni mostly decreased. As revealed by CA,Fe was positively correlated with Mg,Cr,and B. The producing areas of G. elata samples could be effectively identified by DA with Cd,Pb,Cr,Cu,B,and Ni as the main variables,and the accuracy reached up to 85.71%. According to the PCA of mineral elements in G. elata f. glauca from Zhaotong,Yunnan Province,Fe,Cr,Mg,Cd,P,Mn,B,Pb,and Cu exerted a greater influence on G. elata. Conclusion: The determination of mineral elements in G. elata samples contributes to identifying their authenticity and origin due to the easy operation,accurate results,and good stability.