Zingiberene and Curcumene in Wild Tomato
Composition of ginger oil prepared from fresh ginger rhizomes, Zingiber officinale Roscoe (Zingiberaceae) was determined by gas chromatography (GC) and GC‐mass spectrometric techniques. The main sesquiterpene hydrocarbons identified were α‐zingiberene (27–30%), α‐curcumene (8–9%), β‐sesquiphellandrene (4.8%), and bisabolene (3.2%). The function of zingiberene and curcumene as insecticides, repellents, and insect feeding deterrents has been previously reported. Other plant species having similar constituents might be found. Leaves of six wild tomato accessions of Lycopersicon hirsutum f. glabratum (Mull); three accessions of L. hirsutum f. typicum (Humb & Bonpl.); two accessions of L. pennellii Corr. (D'Arcy); one accession of L. pimpinellifolium; and one commercial tomato L. esculentum cv. Fabulous were analyzed. Analysis of L. hirsutum f. typicum (Solanaceae) accessions indicated the presence of zingiberene, curcumene, and other lipophilic secondary metabolites in the leaves of two accessions (PI‐127826 and PI‐127827). An average three month old wild tomato plant of accessions PI‐127826 and PI‐127827 provided 1.93 and 1.30 kg fresh leaves (averaging about 38,307 and 28,130 cm2 exposed leaf surface area, respectively) and produced 19.3 and 10.1 g of zingiberene and curcumene (PI‐127826) and 17.2 and 1.8 g of zingiberene and curcumene (PI‐127827), respectively. Leaf extracts of the wild tomato L. hirsutum f. typicum (accessions PI‐127826 and PI‐127827) can be used as a biorational source of zingiberene and curcumene.