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Protein tyrosine phosphatase 1B (PTP1B) plays an important role as a negative regulator of the insulin and leptin signaling pathways. Therefore, this enzyme is regarded as an attractive therapeutic target for the treatment of type 2 diabetes and obesity. Our screening program for PTP1B inhibitors led to the isolation of four sesquiterpenes and sterol: N,N'-bis[(6R,7S)-7-amino-7,8-dihydro-α-bisabolen-7-yl]urea (1), (6R,7S)-7-amino-7,8-dihydro-α-bisabolene (2), (1R,6S,7S,10S)-10-isothiocyanato-4-amorphene (3), axinisothiocyanate J (4), and axinysterol (5) from the marine sponge Axinyssa sp. collected at Iriomote Island. Of these, compound 1 was the most potent inhibitor of PTP1B activity (IC50=1.9μM) without cytotoxicity at 50μM in two human cancer cell lines, hepatoma Huh-7 and bladder carcinoma EJ-1 cells. Compound 1 also moderately enhanced the insulin-stimulated phosphorylation levels of Akt in Huh-7 cells. Therefore, compound 1 has potential as a new type of anti-diabetic drug candidate possessing PTP1B inhibitory activity.

Indian Sandalwood, Santalum album L. is highly valued for its fragrant heartwood oil and is dominated by a blend of sesquiterpenes. Sesquiterpenes are formed through cyclization of farnesyl diphosphate (FPP), catalyzed by metal dependent terpene cyclases. This report describes the cloning and functional characterization of five genes, which encode two sesquisabinene synthases (SaSQS1, SaSQS2), bisabolene synthase (SaBS), santalene synthase (SaSS) and farnesyl diphosphate synthase (SaFDS) using the transcriptome sequencing of S. album. Using Illumina next generation sequencing, 33.32 million high quality raw reads were generated, which were assembled into 84,094 unigenes with an average length of 494.17 bp. Based on the transcriptome sequencing, five sesquiterpene synthases SaFDS, SaSQS1, SaSQS2, SaBS and SaSS involved in the biosynthesis of FPP, sesquisabinene, β-bisabolene and santalenes, respectively, were cloned and functionally characterized. Novel sesquiterpene synthases (SaSQS1 and SaSQS2) were characterized as isoforms of sesquisabinene synthase with varying kinetic parameters and expression levels. Furthermore, the feasibility of microbial production of sesquisabinene from both the unigenes, SaSQS1 and SaSQS2 in non-optimized bacterial cell for the preparative scale production of sesquisabinene has been demonstrated. These results may pave the way for in vivo production of sandalwood sesquiterpenes in genetically tractable heterologous systems.

The rearranged compound 1, the regular 2 and 3 and the degraded 4 are novel bisabolene-type metabolites that along with the known compounds caespitol, 8-acetylcaespitol, caespitane, caespitenone, laucapyranoid A, and furocaespitane have been isolated from the sea hare Aplysia dactylomela. The structures of these compounds were determined on the basis of spectroscopic evidence. The irregular network of 1 suggested that the halogenated epoxide 6 is a key intermediate for a unified biogenetic pathway of naturally occurring marine algal bisabolene-type metabolites.

The essential oil of Lamiaceae is produced in oil glands on the leaf epidermis and stored in a subcuticular space of these specialized leaf structures. An interesting approach to better understand the variability of the essential oil composition within a plant is the analysis of individual oil glands, which is demonstrated here in the case of an accession of Satureja hortensis L. from Syria. Oil glands from different positions on the plant (petals, calyces, young, medium and old leaves) were analyzed by sampling the content of each oil gland with an SPME fiber. The main compounds identified were γ-terpinene and carvacrol, responsible for the major part (approximately 90%) of the total essential oil composition. The portion of carvacrol was highest in the petals (85%). The calyces showed intermediate values of 75% while carvacrol was equal (58%) at all three ages of leaves (young, medium and old leaves). γ-Terpinene increased from 9% in the calyx to 30% in the leaves. The lanceolate leaves were divided into four sections starting from the base (sector no. 1) to the top (sector no. 4) of the leaf blade. The content of carvacrol increased from 56% in sector no. 1 to 66% in sector no. 2 and decreased subsequently to 53% in sector no. 4. γ-Terpinene showed the opposite trend with a decrease from 32% (sector no. 1) to 25% (sector no. 2) and a steady increase to 36% in sector no. 4. Copyright © 2006 John Wiley & Sons, Ltd.

An Agilent Technologies HP 6890N Plus chromatograph fitted with an HP-5 MS fused silica capillary column and interfaced with an HP 5973 MSD (70 eV) mass spectrometer was used for the GC/MS analysis under the same conditions as above. Compound identification was performed by comparison of retention indices (RI) and MS data with literature data [18, 19]. The oil of C. cascarilloides consisted mainly of hydrocarbon compounds represented by -pinene (10.5%), -caryophyllene (13.5%), -humulene (5.9%), germacrene D (6.0%), and -selinene (6.7%). However, cyclohexanone (6.8%), cis-carane (6.5%), 1-menthol (30.4%), and benzyl benzoate (18.8%) were the main constituents of C. chevalieri. Linalool (7.8%), bicycloelemene (8.0%), -caryophyllene (10.1%), -humulene (7.1%), -bisabolene (9.6%), and -sesquiphellandrene (6.9%) could be identified in higher amounts in C. tonkinensis. Sabinene, linalool, and -caryophyllene were identified in all the oil samples in Table 1. Benzyl benzoate is not known to be a significant constituent of Croton oils.

Chemical investigation of a Formosan sponge Axinyssa sp. has led to the isolation of five nitrogenous bisabolene-type sesquiterpenes 1-5, including two new compounds axinysalines A (1) and B (2). The structures of new compounds were elucidated by analysis of high resolution (HR)-MS and two dimensional (2D)-NMR spectra and comparison of its NMR data with those of known analogues. Compound 1 exhibited moderate to weak cytotoxicity against Molt 4 and K562 cancer cell lines.

Yellow-orange and pink-violet colours of flower plants of Lantana camara from Madagascar were studied with a focus on essential oil (EO) in order to characterize chemotype EO variability. The chemical composition of 73 samples of aerial part EO of L. camara collected each month of the year, at various location, have been characterized by gas chromatography-mass spectrometry (GC-MS). Among the 50 peaks characterized, 43 were identified. The main components changed within the two flower colour types. EO from yellow-orange colour of flowers compared to pink-violet flowers is characterized by high content in terpenic compounds and lower amount in oxygenated compounds. Similar results were observed during seasons, showing that the chemical composition is relatively stable all year long. The components characterizing the pink-violet flower chemotype are: sabinene (9.4–11.3%), 1,8-cineole (3.7–4.6%), linalool (4.8–6.1%), -caryophyllene (11.3–13.6%), -humulene (4.4–5.2%), -bisabolene (1.7–2.3%), -cadinene (0.1–0.4%), ar-curcumene (1.0–1.6%), caryophyllene oxide (1.2–0.7%) and davanone (22.6–25.9%). The components characterizing the yellow-orange flower chemotype are: sabinene (9.0–14.3%), 1,8cineole (0.8–1.0%), linalool (0.4–1.4%), -caryophyllene (25.8–30.8%), -humulene (2.4–2.6%), -bisabolene (13.6–14.9%), -cadinene (0.6–5.2%), ar-curcumene (0.7–2.8%), caryophyllene oxide (0.1–0.4%) and davanone (0.0–0.6%). Chemical composition of nine L. camara industrial EO show that they are composed of mixture of yellow-orange and pink-violet colour of flower chemotypes. Davanone is found in all samples with a mean of 12.4%, linalool (5.4%) and 1,8-cineole (4.1%). For sesquiterpenes, the main are -caryophyllene (15.9%), -bisabolene (1.8%) and -muurolene (1.4%). © 2005 Elsevier B.V. All rights reserved.

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 (HumbBonpl.); 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.

The stem wood oil of Vanillosmopsis erythropappa Schultz-Bip. was analyzed using GC/MS. Forty-three constituents were identified: 31 sesquiterpenoids, one phenylpropane and 11 others. 2-Bisabolene-7, 11-diol and 10-bisabolene-3,7-diol were found for the first time in nature and were characterized using 1H-, 13C-NMR, GC/FTIR and GC/MS analyses.

Essential oils from Gomidesia schaueriana, G. sellowiana, G. spectabilis, G. anacardiifolia, G. palustris and G. tijucensis, collected in Southern Brazil, were analysed by GC and GC–MS. Fifty-two compounds were identified, representing 92–98% of the oil contents. All samples were rich in cyclic sesquiterpenes (about 90%), mainly those from the cadinene and germacrene cyclization pathway. The oils from G. schaueriana, G. spectabilis, G. anacardiifolia and G. palustris were quite similar, with a predominance of β-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, globulol and α-cadinol. G. sellowiana was rich in spathulenol, followed by geranylgeraniol, and G. tijucensis was characterized by the presence of α- and β-selinene. Copyright © 2003 John Wiley & Sons, Ltd.

From the resins of Commiphora kua a novel bisabolene; 6-hydroxy-2-methyl-5-(5'-hydroxy-1'(R),5'-dimethylhex-3'-enyl)-phenol together with two new dammarane triterpenes, 3beta,16beta,20(S),25-tetrahydroxydammar-23-ene and 3beta-acetoxy-16beta,20(S),25-trihydroxydammar-23-ene, have been isolated. In addition, being reported are known compounds identified as 2-methyl-5-(4'(S)-hydroxy-1'(R),5'-dimethylhex-5'-enyl)-phenol, 2-acetoxyfuranodienone, 2-methoxyfuranodienone, 3beta,16beta,20(R)-trihydroxydammar-24-ene and its acetate derivative, 3beta-acetoxy-16beta,20(R)-dihydroxydammar-24-ene, and beta-amyrin and its acetate derivative. 2-Methyl-5-(4'(S)-hydroxy-1'(R),5'-dimethylhex-5'-enyl)-phenol displayed fungicidal activity against Cladosporium cucumernum on TLC assay.

Sunflower is known to produce a variety of bisabolene-type sesquiterpenes and accumulates these substances in trichomes of leaves, stems and flowering parts. A bioinformatics approach was used to identify the enzyme responsible for the initial step in the biosynthesis of these compounds from its precursor farnesyl pyrophosphate. Based on sequence similarity with a known bisabolene synthases from Arabidopsis thaliana AtTPS12, candidate genes of Helianthus were searched in EST-database and used to design specific primers. PCR experiments identified two candidates in the RNA pool of linear glandular trichomes of sunflower. Their sequences contained the typical motifs of sesquiterpene synthases and their expression in yeast functionally characterized them as bisabolene synthases. Spectroscopic analysis identified the stereochemistry of the product of both enzymes as (Z)-γ-bisabolene. The origin of the two sunflower bisabolene synthase genes from the transcripts of linear trichomes indicates that they may be involved in the synthesis of sesquiterpenes produced in these trichomes. Comparison of the amino acid sequences of the sunflower bisabolene synthases showed high similarity with sesquiterpene synthases from other Asteracean species and indicated putative evolutionary origin from a β-farnesene synthase.

Isoprenoids have been identified and used as natural pharmaceuticals, fragrances, solvents, and, more recently, advanced biofuels. Although isoprenoids are most commonly found in plants, researchers have successfully engineered both the eukaryotic and prokaryotic isoprenoid biosynthetic pathways to produce these valuable chemicals in microorganisms at high yields. The microbial synthesis of the precursor to artemisinin--an important antimalarial drug produced from the sweet wormwood Artemisia annua--serves as perhaps the most successful example of this approach. Through advances in synthetic biology and metabolic engineering, microbial-derived semisynthetic artemisinin may soon replace plant-derived artemisinin as the primary source of this valuable pharmaceutical. The richness and diversity of isoprenoid structures also make them ideal candidates for advanced biofuels that may act as "drop-in" replacements for gasoline, diesel, and jet fuel. Indeed, the sesquiterpenes farnesene and bisabolene, monoterpenes pinene and limonene, and hemiterpenes isopentenol and isopentanol have been evaluated as fuels or fuel precursors. As in the artemisinin project, these isoprenoids have been produced microbially through synthetic biology and metabolic engineering efforts. Here, we provide a brief review of the numerous isoprenoid compounds that have found use as pharmaceuticals, flavors, commodity chemicals, and, most importantly, advanced biofuels. In each case, we highlight the metabolic engineering strategies that were used to produce these compounds successfully in microbial hosts. In addition, we present a current outlook on microbial isoprenoid production, with an eye towards the many challenges that must be addressed to achieve higher yields and industrial-scale production.

Essential Oil of Ginger An exhaustive examination of the sesquiterpenes of ginger oil has been carried out. By using a combination of fractional distillation at reduced pressure and chromatography on silver nitrate treated alumina all of the major sesquiterpenes of ginger oil, except zingiberene, have been isolated in a substantially pure form. The presence of (+)-ar-curcumene was confirmed and the absolute configuration at the one asymmetric centre determined for the first time as (I). The bisabolene, shown to be present by previous workers, was conclusively demonstrated to be (-)-b -bisabolene. Two previously unknown sesquiterpenes were isolated. One of these, (1' R, 6S)-2-methyl-6-(4'-methylene cyclohex-2'-enyl) hept-2-ene (II), for which we propose the trivial name (-)- b -sesquiphellandrene, was characterised by the preparation of a solid nitrosite, physical constants, and infrared spectra. The structure was deduced mainly by spectral means while the stereochemistry was revealed by isomerisation to (-)-zingiberene. Isolation of the other new sesquiterpene proved laborious and difficult not allowing a final conclusion as to its structure. However, the chemical and spectral information obtained did reveal it to be a dicyclic sesquiterpene probably closely related to the cadalenic sesquiterpenes. A method was developed for the prediction of the retention times of sesquiterpenes based on the bisabolane and farnesane carbon skeletons. The Epoxide Dehydrogenation Technique The Hildebrand and Sutherland epoxide dehydrogenation technique for positioning double bonds in hydroaromatic systems has been extended and validated. In doing so the structure of dysoxylonene ((p)- d -cadinene, {p)-(III)) was confirmed and the structure of (+)- d -cadinene (III) conclusively demonstrated for the first time. Oleoresin of Ginger By a combination of solvent extraction and dry column chromatography on silica gel, the major pungent principle occurring in fresh ginger oleoresin was isolated. This was characterised as qgingerolq by the preparation of a crystalline methyl ether which had almost identical properties to those described for gingeryl methyl ether by Lapworth and co-workers. Spectral analysis and chemical degradation revealed gingerol and gingeryl methyl ether to have structures (IV) and (V) respectively. These structures are analogous to one of the two possible structures suggested for the compounds by Lapworth and co-workers but they differ in the length of the attached side chain. Another less important pungent constituent was isolated which was shown to have structure (VI) by chemical and spectral means and by analogy with gingerol. The presence of an additional compound having structure (VII) was inferred from degradative experiments. To distinguish the various gingerols it is suggested that the name gingerol be prefixed by a numeral indicating the number of carbon atoms in the aldehyde produced on alkaline degradation e.g. C6-gingerol for the major constituent. Oxidation of C6-gingerol and hydrolysis of the product yielded a glycol of known configuration thus demonstrating that the absolute configuration of the sole asymmetric centre in C6-gingerol is S according to the Cahn, Ingold, Prelog convention. Extraction methods and column chromatography permitted the isolation of another major pungent principle of commercially prepared oleoresins. Spectral and chemical studies showed that this compound had structure (VIII) originally assigned to shogaol by Nomura. C6-Gingerol dehydrated to shogaol under conditions which could be expected to occur during the preparation of ginger oleoresin. It is therefore suggested that shogaol is possibly not a natural compound. The occurence of palmitic acid in substantial quantities in ginger oleoresin was shown for the first time. Parts of this thesis have been published in Aust. J. Chem, 1966, 19, 283 doi:10.1071/CH9660283 and Tetrahedron Let, 1968, 519 doi:10.1016/S0040-4039(01)98796-9.

To facilitate enzyme and pathway engineering, a selection was developed for improved sesquiterpene titers in Saccharomyces cerevisiae . α-Bisabolene, a candidate advanced biofuel, was found to protect yeast against the disruptive action of nonionic surfactants such as Tween 20 (T20). An experiment employing competition between two strains of yeast, one of which makes twice as much bisabolene as the other, demonstrated that growth in the presence of T20 provided sufficient selective pressure to enrich the high-titer strain to form 97% of the population. Following this, various methods were used to mutagenize the bisabolene synthase (BIS) coding sequence, coupled with selection by subculturing in the presence of T20. Mutagenesis targeting the BIS active site did not yield an improvement in bisabolene titers, although mutants were found which made a mixture of α-bisabolene and β-farnesene, another candidate biofuel. Based on evidence that the 3′ end of the BIS mRNA may be unstable in yeast, we randomly recoded the last 20 amino acids of the enzyme and, following selection in T20, found a variant which increased specific production of bisabolene by more than 30%. Since T20 could enrich a mixed population, efficiently removing strains that produced little or no bisabolene, we investigated whether it could also be applied to sustain high product titers in a monoculture for an extended period. Cultures grown in the presence of T20 for 14 days produced bisabolene at titers up to 4-fold higher than cultures grown with an overlay of dodecane, used to sequester the terpene product, and 20-fold higher than cultures grown without dodecane.

Five nitrogenous bisabolene-type sesquiterpenes including the two new compounds axinysalines A (I) and B (II) are isolated from a Formosan sponge Axinyssa sp.

The past decade has witnessed a large influx of research toward the creation of sustainable, biologically derived fuels. While significant effort has been exerted to improve production capacity in common hosts, such as Escherichia coli or Saccharomyces cerevisiae, studies concerning alternate microbes comparatively lag. In an effort to expand the breadth of characterized hosts for fuel production, we map the terpene biosynthetic pathway in a model actinobacterium, Streptomyces venezuelae, and further alter secondary metabolism to afford the advanced biofuel precursor bisabolene. Leveraging information gained from study of the native isoprenoid pathway, we were able to increase bisabolene titer nearly 5-fold over the base production strain, more than 2 orders of magnitude greater than the combined terpene yield in the wild-type host. We also explored production on carbon sources of varying complexity to, notably, define this host as one able to perform consolidated bioprocessing.

The reactivity of terminal and trisubstituted double bonds of monoterpenes with HSCN has been examined by GC giving evidence that kinetics is responsible for the chemoselective addition to terminal double bonds in terpenes. The results show that the addition to the terminal double bond is about 17 times faster than for trisubstituted double bonds and that the presence of the first SCN group in the molecule prevents a second addition. The presence of a hydroxyl or methoxy group in the molecule, decreases the reaction kinetics. Based on these kinetic experiments a two steps synthesis of the natural product 7-isothiocyano-7,8-dihydro-a-bisabolene using bisabolol as starting material, was planned and successfully accomplished.

The novel bisabolene sesquiterpenes 3-6, were isolated from Iostephane heterophylla, using bioguided fractionation. The new compounds were determined to be (12R/12S)-12,13-epoxy-xanthorrhizols (3,4) and (12R/12S)-12,13-dihydro-12,13-dihydroxy-xanthorrizols (5,6) and their structures were characterized by analysis of spectroscopic data and by chemical correlation from xanthorrhizol (2). The stereochemistry at C-12 of 5 was deduced using the modified Mosher experiment. Some of the isolated compounds elicited activity against gram positive and gram negative bacteria, levadura and dermatophytes.

The acidic part of Brazilian lantana oil contains mainly new bisabolene and tricyclic helifolene derivatives. 3-Formyl-helifolen-12-oic acids 14, 16, 11-formyl-helifolen-15-oic acids 10, 12, 6,10-epoxybisabol-2- 18, 20, 22, 24, and -3-en-12-oic acids 19, 21, 23, 25, γ-(26) and ar-curcumen-15-oic acids (27), as well as the known ar-curcumen-12-oic acid (28) and amorpha-4,9,11-trien-12-oic acid, were characterized as their methyl esters. The bifunctionalized methyl helifolenoates 10, 12, 14, 16 were reduced with NaBH4 to the corresponding hydroxy esters 11, 13, 15, 17. Their configuration was clarified by NOED spectra. The helifolen-12- (1a–4a) and -15-oic acids (5a) are present in the acidic part only as traces. Their spectral data were obtained by isolation from an autoxidized fraction of the known aldehydes.1 The parent helifolane (syn. khusiane or allo-cedrane) skeleton 8/9 was prepared by stepwise reduction of esters 1b–4b with LiAlH4 and H2/Pd/C to yield the helifolanols 6 and 7. Treatment of 6, 7 with O-p-tolylchlorothionoformate gave the corresponding thionocarbonates which were reduced with tris(trimethylsilyl)silane to afford helifolanes 8 and 9. Copyright © 2001 John Wiley & Sons, Ltd.

Fermenting baker’s yeast converts the unsaturated aldehydes 7 and 11 into the saturated alcohols 8 and 12, respectively. The microbial saturation of the double bond proceeds in high chemical yields and the stereoselectivity of the reduction is strongly influenced by the E∶Z ratio of the substrate. Enantiopure 8 and 12 are chiral building blocks for the synthesis of bisabolene sesquiterpenes and their usefulness is shown in the preparation of (+)-epijuvabione 1 and (−)-juvabione 3.

The males of Nezara viridula (Heteroptera, Pentatomidae) produce a blend of four terpenoid compounds. The proportion of these four compounds varies among different populations. The terpenoid content of the volatile emission from individual males of a French population was monitored for several days with headspace solid-phase microextraction. The total amount of terpenoid compounds collected on an SPME fiber from one virgin male bug emitting over the course of 1 hr was very variable between samples. More than 50% of males released pheromone, at least during one part of the observation period. The relative percentages of bisabolene, nerolidol, trans-bisabolene epoxide, and cis-bisabolene epoxide were calculated and compared. The proportion of nerolidol in the blend showed a large dispersion between samples and a high coefficient of variation. The percentage values for bisabolene and its trans and cis epoxides were less dispersed, and the coefficients of variation for both epoxides were low. The proportion of trans epoxide relative to the two epoxides, which has been considered characteristic of pheromone strains of N. viridula, showed the smallest coefficient of variation. The repeatability index (RI) varied between 0.57 and 0.85 for the four compounds. Repeatability was particularly high for the two epoxide isomers. Stability in epoxide production was confirmed by statistical analysis (ANOVA), which revealed significant differences in the percentages of cis and trans epoxides between individuals. Correspondingly, the RI of the ratio of trans to cis + trans epoxides was over 0.8. Our study confirms the existence of an interindividual variation of the trans to cis epoxide ratio within populations of Nezara viridula but indicates that each individual reproducibly emits both isomers in the same proportion day after day.

Extracts obtained from hemolymph of sexually mature males of the Caribbean fruit fly Anastrepha suspensa contained four biologically important terpenoid components of the sex pheromone. The four components were identified as farnesene, bisabolene, anastrephin, and epianastrepin based on their relative retention indexes from capillary gas chromatography analysis, using both apolar and polar phase columns and their chemical ionization (isobutane) mass spectra. The ratio of the components in extracts of hemolymph was the same as the ratio present in the volatile blend of pheromone released by sexually mature males during the reproductive period. Studies conducted to determine the effect of age on amounts of these components in hemolymph indicated that they increased from undetectable levels on the day of adult emergence to maximum levels on day eight. The increases in amounts of the components present in hemolymph with increasing age were correlated with increases in amounts of volatile pheromone released by males. Time of day studies showed that the amounts of these components in hemolymph followed the daily pattern of release of volatile pheromone components. Other components of the sex pheromone including ocimene, (Z)-3-nonen-1-ol, (Z,Z)-3,6-nonadien-1-ol and suspensolide were not found in extracts of hemolymph. The data suggest that the hemolymph plays a role in the transport of these pheromone components during sexual signalling. Arch. Insect Biochem. Physiol. 42:225-232, 1999. Published 1999 Wiley-Liss, Inc.

The constituents of the commercial Brazilian lantana oil are mainly bisabolene derivatives, altogether about 65%. The following new natural compounds were characterized by their 1H-NMR and partly 13C-NMR data: 1,12-epoxycadina-3,11-dienes (37, 40), helifolen-15-als (38/39), acora-2,4(15)-dien-11-ol (44), (E)-sesquithujen-12-al (47) and -12-ol (54), italicen-15-al (2,11-cycloacor-3-en-15-al, 52), the 6,10-epoxybisabolen-12-als 49, 50, 53, 58, 60/61, ar-curcumen-15-al (62) and its 10,11-epoxides 76/77, epi-α-bisabolone (69), methyl (E)-trans-α-bergamota-2,10-dien-12-oate (74) and its 2,3-epoxide 80. The so-called helifolen-12-als 35, 36, 42, 43, which were trace constituents of the Iranian Pulicaria gnaphalodes oil, belong to the main constituents (together 7.2%) of the Lantana oil. NaBH4 reduction of 35, 36, 42, 43 yielded the helifolen-12-ols A–D. Their structure was elucidated by NOED and HMBC experiments and an X-ray analysis of the p-bromobenzenesulphonate of helifolen-12-ol D. The helifolen-12-ols A–D are racemates. Therefore, a biogenetic pathway via a bisaboladienyl and an acorenyl cation to the helifolen-12- (35, 36, 42, 43) and -15-als (38/39) is proposed. Copyright © 1999 John Wiley & Sons, Ltd.

( E )-α-Bisabolene synthase is one of two wound-inducible sesquiterpene synthases of grand fir ( Abies grandis ), and the olefin product of this cyclization reaction is considered to be the precursor in Abies species of todomatuic acid, juvabione, and related insect juvenile hormone mimics. A cDNA encoding ( E )-α-bisabolene synthase was isolated from a wound-induced grand fir stem library by a PCR-based strategy and was functionally expressed in Escherichia coli and shown to produce ( E )-α-bisabolene as the sole product from farnesyl diphosphate. The expressed synthase has a deduced size of 93.8 kDa and a pI of 5.03, exhibits other properties typical of sesquiterpene synthases, and resembles in sequence other terpenoid synthases with the exception of a large amino-terminal insertion corresponding to Pro 81 –Val 296 . Biosynthetically prepared ( E )-α-[ 3 H]bisabolene was converted to todomatuic acid in induced grand fir cells, and the time course of appearance of bisabolene synthase mRNA was shown by Northern hybridization to lag behind that of mRNAs responsible for production of induced oleoresin monoterpenes. These results suggest that induced ( E )-α-bisabolene biosynthesis constitutes part of a defense response targeted to insect herbivores, and possibly fungal pathogens, that is distinct from induced oleoresin monoterpene production.

The aerial parts of Artemisia lucentica yielded, in addition to several known compounds, a bicyclic monoterpene ketone, two germacranolides, an eudesmanolide, a 10- epi neudesmanolide, a 2-norelemanolide and three bisabolene derivatives. The stereochemistry of a germacranolide, described as 2α-hydroxyartemorin in a previous investigation of the species, has now been corrected and the compound has been renamed lucentolide.

An investigation of the stem bark of Friesodielsia enghiana led to the isolation of benzyl benzoate and benzyl 2-hydroxybenzoate, two bisabolene sesquiterpenes and nine flavonoids, two of which were new. The new compounds were identified by analysis of their spectroscopic data as 2,5-dihydroxy-7-methoxy-8-methylflavanone and 2,5-dihydroxy-7-methoxy-6-methylflavanone. Three of the co-occurring flavones also have 6- and/or 8-C- methylation.

Aerial parts of Achillea cretica furnished six new 4-oxobisabol-2-enes and the lignans sesartemin B and syringaresinol dimethyl ether.

The novel sesquiterpene glycoside 1-O-[12-O-(12S)- dihydro-12,13-dihydroxyxanthorrizol]-β-L-arabinopyranosyl-(1rarr;2)-β-D-glucopyranoside 1 was identified as a constituent of the ethanol extract of the roots of Iostephane heterophylla, a species used in Mexican traditional medicine, and characterized as the heptaacetyl derivative 2. β-D-glucopyranose, β sitosteryl β-D-glucopyranoside, and stigmasterol were also found as constituents of this extract.

A bioassay-guided fractionation of the aerial parts ofSenecio palmensis resulted in the isolation of two sesquiterpenes, 2,10-bisaboladien-1-one and 11β-acetoxy-5-angeloyloxy-silphinen-3-one. The bisabolene and the silphinene represented 0.012% and 0.024% of the plant dry weight, respectively. Both compounds showed antifeedant activity againstLeptinotarsa decemlineata larvae and adults in short-term choice and no-choice bioassays. Both compounds were also tested against different species of phytopathogenic fungi. The beetles were more sensitive to these compounds in choice than in no-choice assays, with a gradient of increasing sensitivity from second instars to adults. Bisabolene was 45 times less active as an antifeedant than juglone, which was tested as a positive control. The silphinen was more active than the bisabolene, with a range of activity similar to juglone. Furthermore, exposure of fourth instars to these compounds over a 24-hr period resulted in reduced feeding and growth rates. To distinguish between antifeedant and toxic effects, growth efficiencies were calculated as the slope of the regression of relative growth rate on relative consumption rate. The comparison of these results with those of antifeedant simulation and contact toxicity bioassays indicates that feeding inhibition is the primary mode of action of the bisabolene, while the silphinene shows both antifeedant and toxic effects.

To avoid the traditional and time consuming hydrodistillation, the analyses of volatile components in leaves of Citrus aurantium L. were carried out by a simple microwave distillation followed by headspace single drop microextraction (MD-HS-SDME) coupled to gas chromatography–mass spectrometry (GC–MS). The headspace volatile compounds were collected after irradiation using a single drop of n-heptadecan. The extraction conditions were optimized using the relative peak areas as index. The chemical composition of the MD-HS-SDME extracts was confirmed according to their retention indexes and mass spectra. Forty-one components were extracted and identified by using the MD-HS-SDME method. Limonene (62%), Linalool (7.47%), trans-β-Ocimene (3.47%), Caryophyllene (2.05%), α- Bisabolene (1.8%) and Myrcene (1.18%) were the major constituents.

Beside their essential cellular functions, isoprenoids have value as pharmaceuticals, nutriceuticals, pesticides, and fuel alternatives. Engineering microorganisms for production of isoprenoids is relatively easy, sustainable, and cost effective in comparison to chemical synthesis or extraction from natural producers. We introduced genes encoding carotenoid biosynthetic enzymes into the haploid yeast deletion collection to identify gene deletions that improved isoprenoid production. Deletions that showed significant improvement in carotenoid production were further screened for production of bisabolene, an isoprenoid alternative to petroleum-derived diesel. Combining those deletions with other mevalonate pathway modifications increased production of bisabolene from 40mg/L to 800mg/L in shake-flask cultures. In a fermentation process, this engineered strain produced 5.2g/L of bisabolene.

An acid-catalyzed intramolecular [4 + 2] cycloaddition of a non-natural bisabolene is reported. The key cyclocondensation was developed to access cyclic sesquiterpenes from linear phenolic precursors by generating a reactive o-quinone methide intermediate to initiate a cascade reaction. The new method was applied to the first total synthesis of (±)-heliol.

Chinavia and Nezara spp. stink bugs (Heteroptera: Pentatomidae) include over100 species, with highest diversity in Afrotropical and Neotropical regions. Species thus far studied in these genera utilize trans-(Z)-(4 S)-bisabolene epoxide (BE) and cis-(Z)-(4 S)-BE as major sex pheromone components, with species specificity ensured by different ratios of the two compounds. Gas chromatography (GC) and coupled GC-mass spectrometry (GC-MS) analyses of a volatiles from C. ubica males revealed the presence of two BE isomers in approximately a 90:10 ratio, which were shown by microprobe (1) H NMR to be cis-(Z)-BE and trans-(Z)-BE isomers, respectively. Analyses of volatiles from C. impicticornis males suggested the presence of a single isomer, trans-(Z)-BE, in high purity (90 %). The absolute configurations of the isomers produced by C. ubica and C. impicticornis were determined using chiral GC analysis (β-DEX column). Oxidative microchemistry of synthetic standards of cis-(Z)-(4 S)-BE and trans-(Z)-(4R)-BE, and volatiles from male of C. ubica, revealed the absolute stereochemistry of the cis-(Z)-BE to be (1R,2 S,4 S) [cis-(Z)-(4 S) for short]. Similarly, analyses of trans-(Z)-(4 S)-BE and cis-(Z)-(4R)-BE standards, and volatiles from males of C. ubica and C. impicticornis, revealed the absolute stereochemistry of the trans-(Z)-BE to be (1 S,2R,4 S) [trans-(Z)-(4 S) for short]. Olfactometer bioassays with synthetic BEs confirmed attraction of female C. ubica and C. impicticornis to conspecific synthetic pheromone, but not to heterospecific synthetic pheromone. Chinavia impicticornis appeared not to discriminate behaviorally between the conspecific pheromone and its enantiomer. Coupled GC-electroantennography with antennae from females suggested that C. ubica and C. impicticornis possess olfactory receptors for both cis-(Z)-(4 S)-BE and trans-(Z)-(4 S)-BE. The results in this study confirm that C. ubica and C. impicticornis, as for other Chinavia and Nezara spp., utilize cis-(Z)-(4 S)-BE and trans-(Z)-(4 S)-BE as sex pheromone components, with different ratios guaranteeing species specificity. Furthermore, the results suggest that the absolute stereochemistry of BEs may be less important for conspecific recognition than the relative stereochemistry between the epoxide group and the alkyl substituent on the bisabolene ring.

Dactylomelatriol (1), obtained from the sea hare Aplysia dactylomela, is the first naturally occurring omphalane-derived sesquiterpene from the marine environment. From this species the known chamigrene and modified bisabolene sesquiterpenes 2-6 were also isolated. The structure and relative configuration of 1 were established by spectroscopic evidence. Its chemical structure is related to omphalic acid, the unique terrestrial-derived omphalane sesquiterpene isolated from a liverwort. A biogenetic route for this compound is proposed. The antimicrobial activities of compounds 1-6 were evaluated against a panel of microorganisms., This work was supported by the Ministerio de Ciencia e Innovación (BIO2007-61745, SAF2009-08039, SAF2010-16858) and DGUI Gobierno de Canarias (PIO42005, PUB2005/030). We gratefully acknowledge A. Corrales for her technical support of this project.

Turmeric, obtained from the rhizomes of Curcuma longa, is used in South Asia as a traditional medicine for the treatment of epilepsy. To date, in vivo studies on the anticonvulsant activity of turmeric have focused on its principal curcuminoid, curcumin. However, poor absorption and rapid metabolism have limited the therapeutic application of curcumin in humans. To explore the therapeutic potential of turmeric for epilepsy further, we analyzed its anticonvulsant activity in a larval zebrafish seizure assay. Initial experiments revealed that the anticonvulsant activity of turmeric in zebrafish larvae cannot be explained solely by the effects of curcumin. Zebrafish bioassay-guided fractionation of turmeric identified bisabolene sesquiterpenoids as additional anticonvulsants that inhibit PTZ-induced seizures in both zebrafish and mice. Here, we present the first report of the anticonvulsant properties of bisabolene sesquiterpenoids and provide evidence which warrants further investigation toward the mechanistic understanding of their neuromodulatory activity.

Pheromonal volatiles emitted by irradiated and control 5- to 11-day-old Caribbean fruit flies,Anastrepha suspensa (Loew), were collected on Tenax adsorbent filters and quantified by gas chromatography (GC). The components released were identified by comparison of retention times on GC and by mass spectrometry (MS) with authentic synthetic standards. Pharate adults were irradiated with gamma rays from a(60)Co source at a dose rate of 10.3 Gray (Gy)/min. The total dosages given were 30, 50, 70, and 100 Gy. Pheromone volatiles were collected from adult males when they were between 5 and 11 days of age. The compounds quantified were (Z)-3-nonenol and (Z, Z)-3,6-nonadienol, which eluted from the GC column together and were quantified as one peak,β-bisabolene, suspensolide, anastrephin, and epianastrephin. Irradiation with 30 Gy did not significantly reduce any pheromonal components, nor did it change the pheromonal blend. In contrast, suspensolide and bisabolene were significantly reduced in flies irradiated with 50 Gy, while the nonenols and epianastrephin were reduced at the 70-Gy dose. Irradiation with the 100-Gy dose reduced all components with the exception of suspensolide.

From the essential oil of Pulicaria gnaphalodes growing near Tehran some new cadinene derivatives were isolated. The structures of 1,8-oxidocadin-4-enes (6, 7, epimers at C-10), 1(10),4-cadinadien-8α-ol (1), 4,10(14)-cadinadien- and 4,10(14)-muuroladien-8-ols (2–5) could be verified by their 1H- and 13C-NMR spectra. Furthermore, the 8α-epimer 9 of the known α-copaen-8β-ol (10), (Z)-γ-curcumen-12-ol (13a) and the esters (Z)-13b–e could be identified.

From the essential oil of Artemisia sieberi growing near Tehran some new bisabolene derivatives could be isolated. The structures of (−)-dehydro-1,8-sesquicineole (1), (E)-dehydro-1,8-sesquicineol-12-yl acetate (4), bisabola-2,11-dien-10-one inner 1,7-acetal (14) and salsolene ketone 15 could be established by their 1H- and 13C-NMR spectra. Sesquiphellandren-7-ol (11), a trace constituent of the oil, was identified by a comparison of its 1H-NMR spectrum with that of sesquiphellandren-9-ol (bisacurol).

Isomeric compounds reportedly released by mature males of Nezara viridula as attractants for conspecific females are evidently artifacts formed by dimerization of (E)-4-oxo-2-hexenal. Additional analyses of the male-specific volatiles from Italian, Australian, Brazilian, and Japanese populations of N. viridula verify that at least two distinctive pheromone strains exist, but an active synthetic pheromone has not yet been developed. Analyses of volatiles from N. antennata and Acrosternum aseadum males are also reported showing that the native Japanese Nezara sp., and species in the sister genus Acrosternum, produce species-specific blends based on the same compounds as N. viridula: (Z)-α-bisabolene (1-methyl-4-(1,5-dim ethyl-(Z)-1,4- hexadienyl)-cyclohexene), and trans- and cis-1,2-epoxides of (Z)-α-bisabolene. The trans-/cis- 1,2-epoxide ratio of N. antennata is within the range found for most N. viridula populations, but the blend from Japanese N. viridula males deviates radically from those of other conspecific populations.

The aerial parts of three species of the genus Cousinia have been investigated. All three species yielded sesquiterpene lactones, mainly guaianolides. In addition, one of the species yielded oxygenated bisabolene derivatives.

Six Achillea species—Achilleadistans, Achillea setacea, Achillea collina, Achillea ageratum, Achillea ligustica and Achillea aspleniifolia—growing spontaneously in North Italy, were studied in order to analyze the oil composition and to characterize the chromosome numbers and karyotypes. A total of 69 compounds were identified from all oils, including monoterpenes and sesquiterpenes. The main oil components of A distans were bisabolene oxide and linalyl oxide, while A. setacea had high percentages of the sesquiterpenes β-eudesmol, α-bisabolol and caryophyllene oxide. A. ageratum was characterized by the presence of artemisia acetate, artemisia alcohol, 1, 8-cineole and yomogi alcohol, whereas A. ligustica had high percentages of artemisia ketone. A. collina and A. aspleniifolia were particularly rich in chamazulene along with good percentages of germacrene D and other sesquiterpene hydrocarbons. A. distans had a hexaploid(2n=54)chromosome number, A. setacea and A. collina a tetraploid (2n=36) chr...

The isolation of a new diterpene acid 2 from the resin of a variety of Eremophila georgei is described. The structure of the acid was identified by chemical and spectroscopic methods and was shown to contain a C 5 -extended cedrene nucleus. The occurrence of cedrene and bisabolene isoprenologues from an unidentified Eremophila sp. is reported

Fermenting baker’s yeast converts the unsaturated aldehydes 7 and 11 into the saturated alcohols 8 and 12, respectively. The microbial saturation of the double bond proceeds in high chemical yields and the stereoselectivity of the reduction is strongly influenced by the E∶Z ratio of the substrate. Enantiopure 8 and 12 are chiral building blocks for the synthesis of bisabolene sesquiterpenes and their usefulness is shown in the preparation of (+)-epijuvabione 1 and (−)-juvabione 3.

Volatiles from twelve wild Tunisian populations of Lavandula multifida L. growing in different bioclimatic zones were assessed by GC (RI) and GC/MS. Thirty-six constituents, representing 83.48% of the total oil were identified. The major components at the species level were carvacrol (31.81%), β-bisabolene (14.89%), and acrylic acid dodecyl ester (11.43%). These volatiles, together with α-pinene, were also the main compounds discriminating the populations. According to these dominant compounds, one chemotype was revealed, a carvacrol/β-bisabolene/acrylic acid dodecyl ester chemotype. However, a significant variation among the populations was observed for the majority of the constituents. A high chemical-population structure, estimated both by principal component analysis (PCA) and unweighted pair group method with averaging (UPGMA) cluster analysis based on Euclidean distances, was observed. Both methods allowed separation of the populations in three groups defined rather by minor than by major compounds. The population groups were not strictly concordant with their bioclimatic or geographic location. Conservation strategies should concern all populations, because of their low size and their high level of destruction. Populations exhibiting particular compounds other than the major ones should be protected first.

Three new endiandric acid derivatives, beilschmiedic acids D, E and beilschmiedin were isolated from the stem bark of Beilschmiedia anacardioides together with the known compounds bisabolene and tricosanoic acid. Their structures were determined on the basis of spectroscopic analysis. (C) 2009 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.