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Black cumin (Nigella sativa) is a medicinal herb belongs to the Ranunculacea which raised attention due to its pharmaceutical properties. Medical significance of N. sativa mainly attributed to its oxygenated monoterpenes and triterpene saponins which are biosynthesized via the methyl erythritol phosphate (MEP) and MVA (mevalonic acid) pathways, respectively. In order to improve our understanding of monoterpene and triterpene metabolism the partial sequence of a hypothetical monoterpene synthase (MTS) was isolated from N. sativa for the first time and subsequently the relative gene expression of two genes of monoterpene metabolism including geranyl diphosphate synthase (GDS), the isolated monoterpene synthase (MTS) and two genes of triterpene saponins biosynthesis including squalene epoxidase (SQE) and β- amyrin synthase (βAS) were monitored in response to two universal abiotic elicitors including methyl jasmonate (MJ) and salicylic acid (SA), also in different tissues of N. sativa including leaves, stems, roots, capsules and immature seeds. Results of semi quantitative reverse transcription PCR revealed differential regulation of these genes in N. sativa tissues and also in response to abiotic elicitors. Each gene followed a different expression profile and expression level in target tissues. The expression of all studied genes were up-regulated by exogenous application of MJ and SA on N. sativa leaves (at 24 h after treatments), except of GDS which its transcript was not induced by SA. The higher expression of these genes in response to abiotic elicitors might reflect an elevation in the corresponding metabolites; hence elicitation is an applicable tool for enhancement of pharmaceutically active mono/triterpenes in N. sativa.

Feverfew (Tanacetum parthenium) is a medicinal herb which is rich in sesquiterpene lactones. The main sesquiterpene lactone in feverfew is parthenolide. Costunolide has been considered to be the immediate precursor of parthenolide. Parthenolide and costunolide levels in flowers and in leaves collected during the vegetative and generative phase of three feverfew genotypes (diploid, tetraploid and Zardband cv.) and in 2,4-D treated leaves of the diploid genotype were analyzed using UPLC–MS/MS. Parthenolide and costunolide levels showed a similar pattern in all genotypes, and were higher in flowers than in leaves. The developmental pattern of these two compounds was not the same in flowers of the different genotypes and 2,4-D treatment increased both coordinately. In conclusion, we show that genetical, developmental and spatial factors all influence the composition of sesquiterpene lactones in feverfew.