Application of UV/VIS Spectrophotometry and Multivariate Analysis to Characterization of the Species of Solanum sect. Erythrotrichum Child by Ionaldo Jose ´ L. D. Basílio 1 ), Renata K. P. Moura, Jnanabrata Bhattacharyya, and Maria de Fa ´ tima Agra* Laborato ´rio de Tecnologia Farmace ˆutica, Universidade Federal da Paraíba, Caixa Postal, 58051-970, Joa ˜o Pessoa, PB, Brazil (phone: þ 55-83-32167502; fax: þ 55-83-32167511; e-mail: agramf@ltf.ufpb.br) 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 l 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 AlCl 3 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. Introduction. – The genus Solanum L., with ca. 1,500 species, is the largest genus in the Solanaceae family, which is characterized by poricidal anther dehiscence and synapomorphy of the genus [1]. It contains economically important plant species, such as S. lycopersicum L. (tomato) and S. tuberosum L. (potato), as well as many others used in folk medicine [2] . However, the genus exhibits great morphological plasticity in a large number of species and for that reason, several infrageneric taxonomic treatments have been proposed for Solanum that divide the genus into subgenera and sections [ 3] . Analyses of DNA-sequence data have helped in the phylogeny of the genus and the identification of the major groups within Solanum [1] [4] [5] , the largest of which is the Leptostemonum clade, with ca. 350 – 450 species [1]. According to Agra [6], within the Leptostemonum clade, the Solanum sect. Erythrotrichum comprises ca. 23 neotropical species with a distribution ranging from southern Mexico to Peru and southern Brazil. The species of the section Erythro- trichum are distinguished from those of other sections of the Leptostemonum clade by a set of characteristics that include plurifoliate sympodial units and berries of 1 – 2.5 cm in CHEMISTRY & BIODIVERSITY – Vol. 9 (2012) 1114 # 2012 Verlag Helvetica Chimica Acta AG, Zürich 1 ) Doctoral research fellow (2008 – 2012) financed by the Conselho Nacional de Pesquisa e Desenvolvimento (CNPq), Ministe ´rio da Cie ˆncia e Tecnologia.