Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraíba, Caixa Postal, 58051-970 João Pessoa, PB, Brazil.
Chem Biodivers. 2012 Jun;9(6):1114-24. doi: 10.1002/cbdv.201100302.
The UV/VIS spectral characteristics of the standardized extracts of the leaves of 22 Solanum species of the Leptostemonum clade were investigated in the presence of shift reagents with the aid of multivariate analysis, to obtain data in support of the interspecific and subsectional delimitation proposed for Solanum sect. Erythrotrichum. Of these species, 20 belong to the section Erythrotrichum, S. paniculatum is assigned to the section Torva, and S. robustum is not attributed to a defined section. The results indicated characteristic λ(max) (absorbance maxima) for each species as well as the presence of phenolic compounds like flavonoids such as 5-hydroxy flavonols. Hierarchical cluster analysis (HCA) of the data obtained by UV/VIS analysis of the extracts or the extracts with the added shift reagents AlCl₃ and HCl showed a cophenetic correlation coefficient above 0.92 and the classification of the data into three groups. The principal-component analysis (PCA) revealed that the first three principal components accounted for over 98% of the total variance and showed results similar to those obtained by HCA. The present results supported the current proposal for interspecific delimitation of the studied species and partially supported the division of the section into two subsections. The UV/VIS spectral characteristics along with multivariate analysis appear to be a useful approach for distinguishing among species of the genus Solanum.
利用多元分析研究了 Leptostemonum 分支的 22 种茄属植物叶片的标准化提取物的 UV/VIS 光谱特征，以获得支持为 Erythrotrichum 节提出的种间和亚节划分的数据。在这些物种中，20 种属于 Erythrotrichum 节，S. paniculatum 被分配到 Torva 节，而 S. robustum 未归入定义的节。结果表明，每种物种都具有特征性的 λ(max)（吸收最大值），并且存在类黄酮等酚类化合物，如 5-羟基黄酮醇。通过对提取物或加入了 shift 试剂 AlCl₃ 和 HCl 的提取物的 UV/VIS 分析获得的数据的层次聚类分析 (HCA) 显示出协同相关系数高于 0.92，并且数据分为三组。主成分分析 (PCA) 表明，前三个主成分占总方差的 98%以上，结果与 HCA 相似。目前的结果支持对所研究物种的种间划分的现行建议，并部分支持将该节划分为两个亚节。UV/VIS 光谱特征与多元分析相结合似乎是区分茄属植物物种的一种有用方法。
