curcumin and zingiberene

Metabolic module, gene expression pattern and PLS modeling were integrated to precisely identify the terpene synthase responsible for sesquiterpene formation. Functional characterization confirmed the feasibility and sensitivity of this strategy. Plant secondary metabolite biosynthetic pathway elucidation is crucial for the production of these compounds with metabolic engineering. In this study, an integrated strategy was employed to predict the gene function of sesquiterpene synthase (STS) genes using turmeric as a model. Parallel analysis of gene expression patterns and metabolite modules narrowed the candidates into an STS group in which the STSs showed a similar expression pattern. The projections to latent structures by means of partial least squares model was further employed to establish a clear relationship between the candidate STS genes and metabolites and to predict three STSs (ClTPS16, ClTPS15 and ClTPS14) involved in the biosynthesis of several sesquiterpene skeletons. Functional characterization revealed that zingiberene and β-sesquiphellandrene were the major products of ClTPS16, and β-eudesmol was produced by ClTPS15, both of which indicated the accuracy of the prediction. Functional characterization of a control STS, ClTPS1, produced a small amount of β-sesquiphellandrene, as predicted, which confirmed the sensitivity of metabolite module analysis. This integrated strategy provides a methodology for gene function predictions, which represents a substantial improvement in the elucidation of biosynthetic pathways in nonmodel plants.

Topics: Alkyl and Aryl Transferases; Biosynthetic Pathways; Curcuma; Gene Expression Profiling; Genes, Plant; Metabolic Engineering; Monocyclic Sesquiterpenes; Plant Proteins; Reproducibility of Results; Sesquiterpenes

Curcuma longa (Zingiberaceae) is a native plant of southern Asia and is cultivated extensively throughout the warmer parts of the world. Jianghuang and Yujin are rhizome and tuberous root of C. longa, respectively, which were traditionally used as two Chinese medicines. In this paper, pressurized liquid extraction (PLE) and gas chromatography-mass spectrometry (GC-MS) were developed for quantitative determination/estimation of eight characteristic compounds including beta-caryophyllene, ar-curcumene, zingiberene, beta-bisabolene, beta-sesquiphellandrenendrene, ar-turmerone, alpha-turmerone and beta-turmerone in Jianghuang and Yujin. A HP-5MS capillary column (30 m x 0.25 mm i.d.) coated with 0.25 microm film 5% phenyl methyl siloxane was used for separation and selected ion monitoring (SIM) method was used for quantitation. Hierarchical cluster analysis based on characteristics of eight identified peaks in GC-MS profiles showed that 10 samples were divided into two main clusters, Jianghuang and Yujin, respectively. Four components such as ar-curcumene, ar-turmerone, alpha-turmerone and beta-turmerone were optimized as markers for quality control of rhizome (Jianghuang) and tuberous root (Yujin), which are two traditional Chinese medicines, from Curcuma longa.

Topics: Chromatography, High Pressure Liquid; Cluster Analysis; Curcuma; Curcumin; Drugs, Chinese Herbal; Gas Chromatography-Mass Spectrometry; Ketones; Molecular Structure; Monocyclic Sesquiterpenes; Plant Tubers; Polycyclic Sesquiterpenes; Quality Control; Rhizome; Sesquiterpenes; Technology, Pharmaceutical; Toluene

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 alpha-zingiberene (27-30%), alpha-curcumene (8-9%), beta-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. esculentumm 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.

Topics: Chromatography, Gas; Curcumin; Gas Chromatography-Mass Spectrometry; Monocyclic Sesquiterpenes; Plant Extracts; Plant Leaves; Sesquiterpenes; Solanum lycopersicum; Zingiber officinale