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Three novel terpenes, named buddlindeterpene A, B and C, were isolated from Buddleia lindleyana Fort. The complete 1H and 13C NMR assignments of the three compounds were carried out by using DEPT, COSY, HMQC and HMBC techniques. The stereochemistry of 1 and 3 was confirmed by single-crystal x-ray diffraction analysis.
Three cerebrosides 2, 3, and 5 and two terpene glycosides 1 and 4 have been isolated from the methanol extract of the root of Aster scaber. Their structures were determined as 3-O-beta-D-glucuronopyranosyl-oleanolic acid methyl ester (1), (2S, 3S, 4R, 2'R, 8Z, 15'Z)-N-2'-hydroxy-15'-tetracosenoyl-1-O-beta-D-glucopyranosyl-4-hydroxy-8-sphingenine (2), (2S, 3S, 4R, 8Z)-N-octadecanoyl-1-O-beta-D-glucopyranosyl-4-hydroxy-8-sphingenine (3), 1alpha-hydroxy-6beta-O-beta-D-glucosyl-eudesm-3-ene (4), and (2S, 3S, 4R, 2'R, 8Z)-N-2'-hydroxy-hexadecanoyl-1-O-beta-D-glucopyranosyl-4-hydroxy-8-sphingenine (5) on the basis of spectroscopic methods.
To evaluate the efficacy of a terpene mixture (rowatinex) compared to ibuprofen, patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) were randomly selected to either receive rowatinex 200 mg t.i.d. or ibuprofen 600 mg t.i.d. After a 6-week treatment, the decrease in the mean total NIH-CPSI score was significant in both groups from 21.4 to 15.3, (6.1 (p < 0.01) and from 21.2 to 16.8, (4.4 (p = 0.04) in the rowatinex and ibuprofen group, respectively. The rate of definite improvement as defined as 25% improvement in the total score was superior (p = 0.04) in the rowatinex group (68%) versus the ibuprofen group (40%). Judging from these results, rowatinex gave significant symptomatic relief and may be of benefit for many men diagnosed with CP/CPPS. Further, including the placebo-controlled studies are necessary to define its role in the management of this difficult to treat disease.
Upon herbivore attack, maize (Zea mays L.) emits a mixture of volatile compounds that attracts herbivore enemies to the plant. One of the major components of this mixture is an unusual acyclic C11 homoterpene, (3E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), which is also emitted by many other species following herbivore damage. Biosynthesis of DMNT has been previously shown to proceed via the sesquiterpene alcohol, (E)-nerolidol. Here we demonstrate an enzyme activity that converts farnesyl diphosphate, the universal precursor of sesquiterpenes, to (3S)-(E)-nerolidol in cell-free extracts of maize leaves that had been fed upon by Spodoptera littoralis. The properties of this (E)-nerolidol synthase resemble those of other terpene synthases. Evidence for its participation in DMNT biosynthesis includes the direct incorporation of deuterium-labeled (E)-nerolidol into DMNT and the close correlation between increases in (E)-nerolidol synthase activity and DMNT emission after herbivore damage. Since farnesyl diphosphate has many other metabolic fates, (E)-nerolidol synthase may represent the first committed step of DMNT biosynthesis in maize. However, the formation of this unusual acyclic terpenoid appears to be regulated at both the level of (E)-nerolidol synthase and at later steps in the pathway.
A partially purified and lyophilized preparation of (+)-alpha-pinene cyclase from sage (Salvia officinalis) was shown to convert geranyl pyrophosphate to the monoterpene olefins alpha-pinene, camphene, limonene, and myrcene, in hexane with the addition of 0.1 to 10% water. This constitutes the first report of catalysis by a terpene cyclase in "non-aqueous" media. The relative proportions of olefinic products, metal ion requirement, pH optimum, temperature response, and time course of the enzymatic conversion were determined. The cyclase was shown to be stabilized with respect to temperature and time by the use of hydrocarbon solvent, and, in all other characteristics, to exhibit properties closely resembling those observed in aqueous media.
The chiral discrimination of enantiomeric derivatives of alpha-pinene was studied using amylose tris(3,5-dimethylphenylcarbamate) as a chromatographic stationary phase. The effect of structural features of these enantiomeric pairs on their chromatographic resolution was systematically studied to understand further the correlation between these features and chiral discrimination by the carbamated amylose. Structural analysis by molecular mechanics indicated that the conformation of the alpha-pinene skeleton was preserved with substitution in all its derivatives. However, in spite of the rigidity of the molecular backbone of these molecules, their resolution capabilities were different. Apparently, the site of the hydrogen-bonding substituents affected chiral discrimination by the stationary phase rather than conformational changes. Separation was achieved in spite of the fact that none of the members in the series had an aromatic moiety, and therefore pi-pi interactions with the stationary phase were insignificant. Hence it was concluded that the most important interaction of the terpene derivatives with the carbamated amylose was hydrogen bonding.
A quantitative assay for the analysis of sesquiterpene synthases, wherein each reaction mixture is formulated in glass gas chromatography vials, overlaid with organic solvent such as ethyl acetate, and subsequently vortexed to extract hydrocarbon reaction products into the organic phase after a suitable incubation period, was developed. The product-enriched organic phase is then sampled in an automated fashion and injected directly into a gas chromatograph-mass spectrometer without further workup for analysis and quantification of hydrocarbon products. Application of the vial assay to the analysis of amorpha-4,11-diene synthase (ADS), a sesquiterpene synthase, demonstrated the sensitivity of the assay for detection of major and minor reaction products and most notably for the identification of several sesquiterpene products that had escaped previous detection. A steady-state kinetic analysis of tobacco 5-epi-aristolochene synthase (TEAS), another sesquiterpene synthase, validated the quantitative nature of the assay, providing an alternative means to the established method of using radiolabeled substrate, extraction, and scintillation counting. This simplified assay provides a standardized method to facilitate analysis of terpene synthases and diverse mutant enzyme libraries by supplanting the common practice of using larger scale reactions, multiple extractions, and evaporative concentration of the organic phase prior to gas chromatography-mass spectrometry (GC-MS) analysis.
Phenalinolactones are terpene glycosides with antibacterial activity. A striking structural feature is a highly oxidized gamma-butyrolactone of elusive biosynthetic origin. To investigate the genetic basis of the phenalinolactones biosynthesis, we cloned and sequenced the corresponding gene cluster from the producer strain Streptomyces sp. Tü6071. Spanning a 42 kbp region, 35 candidate genes could be assigned to putatively encode biosynthetic, regulatory, and resistance-conferring functions. Targeted gene inactivations were carried out to specifically manipulate the phenalinolactones pathway. The inactivation of a sugar methyltransferase gene and a cytochrome P450 monoxygenase gene led to the production of modified phenalinolactone derivatives. The inactivation of a Fe(II)/alpha-ketoglutarate-dependent dioxygenase gene disrupted the biosynthetic pathway within gamma-butyrolactone formation. The structure elucidation of the accumulating intermediate indicated that pyruvate is the biosynthetic precursor of the gamma butyrolactone moiety.
The effects of water deficit stress and plant water potential (psi) on monoterpene and sesquiterpene leaf emissions from Rosmarinus officinalis, Pinus halepensis, Cistus albidus and Quercus coccifera were studied over 11 days of water withholding (from t(1) to t(11)), after substrates had achieved their field capacity (control pots: t(0)). Volatile compounds were sampled from the same twig per plant all throughout the study, using a dynamic bag enclosure system. Volatiles, collected in Tenax TA, were studied by means of GC-FID and GC-MS. Monoterpene emissions of water stressed plants (t(1)-t(11)) were either similar to those of control seedlings (R. officinalis and Q. coccifera) or higher (P. halepensis and C. albidus). By contrast, sesquiterpene emissions were strongly reduced or inhibited after four days of water withholding, particularly for R. officinalis, thus altering terpene emission composition. Despite the positive effect of water stress on leaf monoterpene emissions of P. halepensis and C. albidus, the significant correlation between these emissions and psi showed a slow decrease of these emissions over long term water deficit periods. This contrasted with the rapid decline of sesquiterpene emissions of R. officinalis according to lower values of psi. These results provide an overall picture of the different responses of monoterpene and sesquiterpene emissions to progressive water loss. They also reveal the utility of using psi for estimating some emission rates of some species according to drought conditions.
A reverse-flow micellar electrokinetic chromatographic (RF-MEKC) method was developed for the simultaneous qualitative determination of 10 components consisting of the flavonol glycosides, rutin and quercitrin, the flavonol aglycones, isorhamnetin, kaempferol and quercetin, the terpene trilactones, ginkgolides A, B, C and J and the sesquiterpene, bilobalide. This method was used to fingerprint Ginkgo biloba solid oral dosage forms and validated for the quantitation of the marker compounds, rutin and quercetin in some commercial products. In addition to the usual variables, the influence of some essential background electrolyte (BGE) components such as sodium dodecyl sulphate (SDS) and -cyclodextrin concentrations were investigated. A polyimide fused-silica square capillary column (75 microm I.D. x 360 microm O.D.) with a total length of 60.0 cm and effective length of 45.0 cm was used for the separation. The final BGE consisted of 20 mM phosphoric acid, 40 mM SDS and 12 mM -cyclodextrin (pH 2.2) using reverse polarity with a voltage of -17.5 kV. Samples were injected electrokinetically at -5 kV for 3 s for the qualitative analysis and hydrodynamically at 20 mbar for 0.6 s for the quantitative assay. The total run time was 22 min and the limits of detection were 3.13 microg/ml and 1.88 microg/ml for rutin and quercetin, respectively. Fingerprint profiles of the solid oral dosage forms and the results of the quantitative analysis indicated that there were major discrepancies in the marker content between products and illustrates the value of this method for use as a procedure to assess product quality of commercially available Ginkgo biloba products.
To develop the suitable film formulations of propranolol hydrochloride (PPL) containing enhancers for transdermal use, polymeric film formulations were prepared by employing ethyl cellulose (EC) and polyvinyl pyrrolidone (PVP) as a film former, and dibutyl phthalate (DBP) as a plasticizer. Terpenes such as menthol and cineole, and propylene glycol (PG) were also employed as a chemical enhancer to improve the skin penetration of PPL. The film preparations were characterized in physical properties such as uniformity of drug content, thickness and moisture uptake capacity. Release and skin permeation kinetics of PPL from film preparations were examined in the in vitro studies using a Franz-type diffusion cell. The uniformity of drug content was evidenced by the low S.D. values for each film preparation. The moisture uptake capacity and drug release rate increased with the increase of PVP in each preparation. Enhancers examined in the present study also increased the moisture uptake capacity and release rate of PPL from the film preparations. Increasing the concentration of PPL from 1 to 2 mg/cm2 in the film enhanced the release rate of PPL, while no effect of enhancer concentrations on the release rate from the film preparations was observed. In vitro skin permeation study showed that cineole was the most promising enhancer among the enhancers examined in the present study and suggested that the suitable compositions of film preparation would be EC:PVP:PPL=6:3:4 with 10% (w/w) cineole and 7:2:4 with 10% (w/w) PG and cineole, which provided high skin permeation rates at 93.81+/-11.56 and 54.51+/-0.52 microg/cm2/h, respectively.
When subjected to a Picea abies suspension cell culture, beta-pinene, either one of the pure enantiomers or the racemate, was transformed mainly to trans-pinocarveol along with the minor products myrtenol, alpha-terpineol, pinocarvone, myrtenal and cis-pinocarveol. The absolute configuration of the major products corresponded to that of the starting beta-pinene enantiomer. Some of the primary transformation products, i.e. (1S)-cis- and (1S)-trans-pinocarveol, (1R)-myrtenol and (4S)-alpha-terpineol, were also tested as substrates of the P. abies suspension culture. They reacted more slowly than beta-pinene but, except for (4S)-alpha-terpineol, they were all transformed. Thus, (1R)-myrtenol was converted into both (1R)-myrtenal and (1R)-myrtanol, whereas (1S)-trans-pinocarveol was converted into (1S)-pinocarvone. (4R)-Limonene was slowly transformed by the suspension culture into limonene-(1,2)-epoxide as the major product, with carveol, perillyl alcohol and 1,8-cineole as minor products. Autoxidation of terpenes in cell-free nutrient medium was investigated in detail. Alpha-pinene and beta-pinene were both autoxidized to a certain extent, while limonene remained unaffected. The rate of the autoxidation was more than one order of magnitude slower than that of the biotransformation. Moreover, different products were formed by autoxidation than by biotransformation.
Liquid chromatography/atmospheric pressure chemical ionization ion trap mass spectrometry (LC/APCI-ITMS) was applied to determine the concentration of terpene lactone in plasma of guinea pigs after chronic administration of Ginkgo biloba extract enriched in ginkgoterpenes in free form (IDN 5380) or complexed with soy phosphlipids (IDN 5381). Oral treatment of the animals with ginkgoterpenes resulted to inhibit the bronchoconstriction (ITP) and the concomitant increase of the levels of thromboxane B2 (TXB2) in the circulation caused by histamine (HIST) and platelet activating factor (PAF) in normal guinea pigs or by ovalbumin (OA) in actively sensitized guinea pigs. To compare the protective activities of G. biloba forms (IDN 5380 and IDN 5381), ED50 and dose ratio (DR) values for both parameters (ITP and TXB2) were evaluated. The phytosomic form (IDN 5381) significantly reduced (two- to four-fold as compared to free form, P < 0.001) the HIST, PAF or OA-induced airway changes and TXB2 release. In addition it has been observed that the absence of ginkgolide C (GC) in plasma samples (in human and animals) was due to its rapid methylation.
A reversed phase high performance liquid chromatographic method with evaporative light scattering detection (RP-HPLC-ELSD) was developed for the quantitative determination of the terpene trilactones, ginkgolide A, B, C and J and the sesquiterpene, bilobalide in Ginkgo biloba solid oral dosage forms. Separation was achieved using a minibore Phenomenex Luna (5 microm) C18 column with dimensions 250 mm x 2.00 mm maintained at a temperature of 45 degrees C. A simple gradient method using a mobile phase of methanol:water and a flow rate of 350 microl/min facilitated baseline separation of the selected marker compounds within 14 min. The ELSD parameters affecting the detector response were optimized prior to the validation. The limits of detection and quantification were 31.25 and 62.50 ng, respectively. The percentage relative errors of the recovery ranged between -3.16 and +1.88 and both intra-day and inter-day percentage standard deviations were all better than 6%. This method was used to assay commercially available Ginkgo biloba products and proved to be suitable for the routine analysis of such products for quality control purposes.
Six different olibanum samples with certified botanical origin were analyzed by headspace SPME-GC/MS in order to define their mono-, sesqui- and diterpenic composition, as pertinent criteria of identification. Boswellia carteri and Boswellia sacra olibanum have quite similar chemical composition, with isoincensole acetate as the main diterpenic biomarker. Although Boswellia serrata olibanum also exhibits this biomarker, the presence of methylchavicol, methyleugenol and an unidentified oxygenated sesquiterpene distinguishes B. serrata olibanum from the two other species. The characteristic chemical compounds of Boswellia papyrifera are the diterpenic biomarkers incensole and its oxide and acetate derivatives, n-octanol and n-octyl acetate. Boswellia frereana olibanum is devoid of diterpenes of the incensole family but contains a high amount of many dimers of alpha-phellandrene. The chemical composition of olibanum, which is demonstrated to be different for each Boswellia species allowed the determination of the taxonomic origin of frankincense samples purchased on various markets in East Africa, in the Near East and in Yemen. Moreover, terpenic fingerprints allowed the botanical origin of olibanum used in traditional incense mixtures to be identified. Furthermore, this study gave us the opportunity to assign a botanical origin to an archaeological frankincense sample.
HeI photoelectron spectra of three terpenes: alpha-pinene, pulegone and cembrene have been measured. The analysis of their electronic structure is based on the comparison of measured spectra with those of related compounds and on the comparison with molecular structures of studied compounds. We discuss changes in ionization energies of C-C double bonds which are situated at different positions along the rings.
The solubility isotherms of nineteen aromatics and terpenes in aqueous hydroxypropyl-beta-cyclodextrin were determined to be straight lines. This is explained by the host-guest complexation which is characteristic for the whole class of cyclodextrins and derivatives. The slopes of the solubility isotherms correlate with Sterimol L and log P(ow) as descriptors of the steric fit and hydrophobicity match, in accord with the qualitative representation of the phenomenon.
The stoichiometric coefficients and apparent formation constants (Kf) of alpha-terpineol, thymol, geraniol and linalool complexes with beta-cyclodextrin (beta-CD) were determined using HPLC with a porous graphitic carbon (PGC) chromatographic support. Measurements were performed with four different methanol-water mobile phases. All the terpene derivatives under study form 1:1 guest-CD complexes. Graphs of Kf as a function of the mobile phase composition appeared different from those classically described for RP-C18 and suggest that the PGC stationary phase could play an active role in the complexation process. Solute-CD inclusion and solute-stationary phase interactions may be involved in this specific behavior.