Volatile organic compounds from Pachyrhizus ferrugineus and Pachyrhizus erosus (Fabaceae) leaves

Abstract

In México, Pachyrhizus erosus (Fabaceae) commonly called "jícama", is widely known for its edible tubers. It is cultivated since the pre-Columbian period, and the powdered seeds have been used for the treatment of mange, lice, and fleas, due to their content of rotenone, a well-known insecticidal compound. On the other hand, P. ferrugineus, a wild species can only be found in the Tropical Forests, and has no commercial value. It is known that plants release volatile organic compounds (VOCs) showing qualitative and quantitative differences if are wild or cultivated. VOCs are also involved as repelling or attracting chemical signals to insect herbivores, and their natural enemies. Until now, the VOCs of the leaves of P. erosus and P. ferrugineus have not been investigated. In the present contribution the VOCs of both species were characterized by headspace solid-phase (HS-SPME) extraction and gas chromatography-mass spectrometry (GC-MS-TOF). In P. erosus 21 VOCs were found, being the most abundant: cyclohexanone (32.8%), 3-hexen-1-ol (Z) (32.7%), 3-hexenal (Z) (10.5%). The majoritarian compounds were C6 or C5 derivatives In P. ferrugineus, the most abundant VOCs were: 5-hexene-1-ol acetate (51.5%), undecanal (22.4%), 2-hepten-1-al (14.5%). The majoritarian compounds were C6, C7 or C11 derivatives.