Discrimination of different valerian types with an electronic nose

odors of two valerian species (valeriana carnosa sm. and valeriana clarionifolia phil.), grown in the nordwest zone of chubut province (argentina) were distinguished with an electronic nose (en) moses ii (modular sensor system) and both valerian varieties were chemically analyzed with tlc (thin layer chromatography). the two valerian species were gathered between march 2000 and november 2001. specimen of valeriana clarionifolia phil. were gathered from two different regions of the same chubut zone: wood-steppe and steppe. en and tlc data were compared with those of valeriana officinalis coming from india. the odors of valerian species were clearly discriminated with the en enabling to separate not only the different varieties but also the regions from where they were cropped. the statistical principal component analysis (pca) method was used to evaluate the en data. tlc analysis was performed to identify the active compounds of valerians. in a previous work [1] the authors determined that different species were separated because they exhibited a different concentration of active compounds (like the valerenic acid and valepotriates)whose concentration is closely related to sedative properties of valerians.