Showing papers on "Terpene published in 2005"

Hydrolysis of terpenyl glycosides in grape juice and other fruit juices: a review

Abstract: The importance of monoterpenes on varietal flavour of must and other fruit juices has been reviewed. These compounds were mainly found linked to sugar moieties in grape juice and wines, showing no olfactory characteristics. In this way, analytical techniques developed to study these compounds, in both free or glycosidically forms, are discussed. Mechanisms to liberate terpenes were studied, making a comparative study between acidic and enzymic hydrolysis of terpene glycosides; as enzymic hydrolysis seems to be the most natural way to liberate terpenes, the ability to use glycosidases from grapes, yeasts, bacterial or exogenous, i.e. fungal commercial preparations, were reviewed. Re-arrangements of terpenes after acidic hydrolysis of glycoconjugated are discussed as well as potential adverse effects of enzyme preparations.

De novo synthesis of monoterpenes by Saccharomyces cerevisiae wine yeasts.

Abstract: This paper reports the production of monoterpenes, which elicit a floral aroma in wine, by strains of the yeast Saccharomyces cerevisiae. Terpenes, which are typical components of the essential oils of flowers and fruits, are also present as free and glycosylated conjugates amongst the secondary metabolites of certain wine grape varieties of Vitis vinifera. Hence, when these compounds are present in wine they are considered to originate from grape and not fermentation. However, the biosynthesis of monoterpenes by S. cerevisiae in the absence of grape derived precursors is shown here to be of de novo origin in wine yeast strains. Higher concentration of assimilable nitrogen increased accumulation of linalool and citronellol. Microaerobic compared with anaerobic conditions favored terpene accumulation in the ferment. The amount of linalool produced by some strains of S. cerevisiae could be of sensory importance in wine production. These unexpected results are discussed in relation to the known sterol biosynthetic pathway and to an alternative pathway for terpene biosynthesis not previously described in yeast.

Terpenoids As Therapeutic Drugs and Pharmaceutical Agents

Abstract: Terpenoids, also referred to as terpenes, are the largest group of natural compounds. Many terpenes have biological activities and are used for the treatment of human diseases. The worldwide sales of terpene-based pharmaceuticals in 2002 were approximately US $12 billion. Among these pharmaceuticals, the anticancer drug Taxol® and the antimalarial drug Artimesinin are two of the most renowned terpene-based drugs. All terpenoids are synthesized from two five-carbon building blocks. Based on the number of the building blocks, terpenoids are commonly classified as monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), and sesterterpenes (C25). These terpenoids display a wide range of biological activities against cancer, malaria, inflammation, and a variety of infectious diseases (viral and bacterial). In last two decades, natural-product bioprospecting from the marine environment has resulted in hundreds of terpenoids with novel structures and interesting bioactivities, with more to be discovered in the future. The problem of supply is a serious obstacle to the development of most terpenoid compounds with interesting pharmaceutical properties. Although total chemical synthesis plays a less important role in the production of some terpenoid drugs, it has contributed significantly to the development of terpenoid compounds and terpene-based drugs by providing critical information on structure-activity relationships (SAR) and chiral centers as well as generating analog libraries. Semisynthesis, on the other hand, has played a major role in the development and production of terpenoid-derived drugs. Metabolic engineering as an integrated bioengineering approach has made considerable progress to produce some terpenoids in plants and fermentable hosts. Cell culture and aquaculture will provide a solution for the supply issue of some valuable terpenes from terrestrial and marine environments, respectively. Recent advances in environmental genomics and other “-omics” technologies will facilitate isolation and discovery of new terpenoids from natural environments. There is no doubt that more terpenoid-based clinical drugs will become available and will play a more significant role in human disease treatment in the near future.

Selected oxidized fragrance terpenes are common contact allergens

Abstract: Terpenes are widely used fragrance compounds in fine fragrances, but also in domestic and occupational products. Terpenes oxidize easily due to autoxidation on air exposure. Previous studies have shown that limonene, linalool and caryophyllene are not allergenic themselves but readily form allergenic products on air-exposure. This study aimed to determine the frequency and characteristics of allergic reactions to selected oxidized fragrance terpenes other than limonene. In total 1511 consecutive dermatitis patients in 6 European dermatology centres were patch tested with oxidized fragrance terpenes and some oxidation fractions and compounds. Oxidized linalool and its hydroperoxide fraction were found to be common contact allergens. Of the patients tested, 1.3% showed a positive reaction to oxidized linalool and 1.1% to the hydroperoxide fraction. About 0.5% of the patients reacted to oxidized caryophyllene whereas 1 patient reacted to oxidized myrcene. Of the patients reacting to the oxidized terpenes, 58% had fragrance-related contact allergy and/or a positive history for adverse reaction to fragrances. Autoxidation of fragrance terpenes contributes greatly to fragrance allergy, which emphasizes the need of testing with compounds that patients are actually exposed to and not only with the ingredients originally applied in commercial formulations.

Foraging in Chemically Diverse Environments: Energy, Protein, and Alternative Foods Influence Ingestion of Plant Secondary Metabolites by Lambs

Abstract: Interactions among nutrients and plant secondary metabolites (PSM) may influence how herbivores mix their diets and use food resources. We determined intake of a food containing a mix of terpenoids identified in sagebrush (Artemisia tridentata) when present in isoenergetic diets of increasing concentrations of protein (6, 9, 15, or 21% CP) or in isonitrogenous diets of increasing concentrations of energy (2.17, 2.55, 3.30, or 3.53 Mcal/kg). Lambs were offered choices between those diets with or without terpenes or between diets with terpenes and alfalfa hay. Intake of the diets with terpenes was lowest with the lowest concentrations of protein (6%) and energy (2.17 Mcal/kg) in the diets, and highest with diets of 15% CP and 3.53 Mcal/kg. In contrast, when terpenes were absent from the diets, lambs consumed similar amounts of all four diets with different concentrations of protein, and more of the diets with intermediate amounts of energy. When given a choice between the diet with or without terpenes, lambs preferred the diet without terpenes. When lambs were offered choices between terpene-containing diets and alfalfa, energy and protein concentrations influenced the amount of terpenes animals ingested. Energy densities higher than alfalfa, and protein concentrations higher than 6%, increased intake of the terpene-containing diet. Thus, the nutritional environment interacted with terpenes to influence preference such that lambs offered diets of higher energy or protein concentration ate more terpenes when forced, but not when offered alternative food without terpenes. The nutrients supplied by a plant and its neighbors likely influence how much PSM an animal can ingest, which in turn may affect the dynamics of plant communities, and the distribution of herbivores in a landscape. We discuss implications of these findings for traditional views of grazing refuges and varied diets in herbivores.

Composition and antimicrobial activity of Helichrysum italicum essential oil and its terpene and terpenoid fractions

Abstract: The essential oil of Helichrysum italicum (Roth) G. Don from Croatia has been fractionated into terpene and terpenoid fractions and analyzed using GC/MS. Fifty-two compounds were identified. The main hydrocarbons of the oil were α-pinene (10.2%), α-cedrene (9.6%) aromadendrene (4.4%), β-caryophyllene (4.2%), and limonene (3.8%), while the main oxygen-containing compounds were neryl acetate (11.5%), 2-methylcyclohexyl pentanoate (8.3%), 2-methylcyclohexyl octanoate (4.8%), and geranyl acetate (4.7%). The essential oil and its terpene and terpenoid fractions were evaluated for antibacterial and antifungal activities. The screening of antimicrobial activity was conducted by a disc diffusion test and the minimum inhibitory concentration was determined against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The essential oil and its terpenoid fraction exhibited higher antimicrobial activity with respect to the terpene fraction. The antimicrobial activities of the oil and its terpenoid fraction were more pronounced against Staphylococcus aureus and Candida albicans.

Induction of de novo volatile terpene biosynthesis via cytosolic and plastidial pathways by methyl jasmonate in foliage of Vitis vinifera L

Abstract: The terpene biosynthesis in leaves of Vitis vinifera L. cv. Morio Muskat was studied using methyl jasmonate to induce defensive responses in vivo. The experiments demonstrated the strong activation of the de novo biosynthesis of terpenoids via the octadecanoid-signaling cascade and release of the compounds to the gas phase. Feeding experiments with [5,5-2H2]-1-deoxy-d-xylulose and [5,5-2H2]mevalonic acid lactone allowed the investigation of the dynamic allocation of resources via the mevalonic acid and 1-deoxy-d-xylulose/2-C-methyl-d-erythritol 4-phosphate (DOXP/MEP) pathway under induced conditions and after treatment with the specific inhibitors mevastatin and fosmidomycin. The experiments reveal that monoterpenes are almost exclusively synthesized via the DOXP/MEP pathway, whereas sesquiterpenes are generated via both pathways at approximately equal rates. The biosynthesis of the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene was not affected by mevastatine or fosmidomycin. Keywords: Vitaceae; 1-deoxy-d...

Improved Anti-Inflammatory Activity of Three New Terpenoids Derived, by Systematic Chemical Modifications, from the Abundant Triterpenes of the Flowery Plant Calendula officinalis†

Abstract: Rings A, D and E of faradiol (1), and ring E of both arnidiol (10) and calenduladiol (4) have been subjected to various selective chemical manipulations to modify polarity, water affinity, H-bonding, sterics, and number of aromatic groups of these anti-inflammatory natural compounds. A total of 15 new and four known pentacyclic triterpenoids have been obtained in this way. Some 13 terpenoids were evaluated for their topical anti-inflammatory activities with respect to inhibition of croton oil induced ear oedema in mouse. Three derivatives of 1, the C(16) benzyl ether 15, the C(30) aldehyde 24, and the C(30) primary alcohol 25 showed significantly improved anti-inflammatory potencies, which is relevant for (future) structure-activity-relationship (SAR) studies.

Exploiting PdII and TiIII Chemistry To Obtain γ-Dioxygenated Terpenoids: Synthesis of Rostratone and Novel Approaches to Aphidicolin and Pyripyropene A

Abstract: In nature there are several terpenoids with a characteristic γ-dioxygenated system on the A ring, and many of them show interesting pharmacological properties. We have developed a novel strategy for the synthesis of these terpenoids involving three stages: (a) the selective epoxidation of commercial polyenes, (b) titanium(III)-catalyzed cyclization of the epoxypolyprenes thus obtained, and (c) Pd-mediated remote functionalization of the equatorial methyl group attached at C-4 on ring A of the cyclic terpenoid thus formed. This strategy has proved to be useful for the synthesis of the natural labdane rostratone (1) and related terpenoids, as well as for advanced synthetic approaches toward the pharmacologically active products aphidicolin (2) and pyripyropene A (3).

Enantioselective alkynylations of aromatic and aliphatic aldehydes catalyzed by terpene derived chiral amino alcohols

Abstract: Enantioselective alkynyl zinc additions to aromatic and aliphatic aldehydes have been studied using terpene derived chiral amino alcohol ligands. The limonene derived amino alcohol (1 R ,2 R ,5 S )-2-methyl-5-(1-methylethenyl)-2-(1-pyrrolidinyl)cyclohexanol gave the most promising results. Chiral propargylic alcohols were obtained in good yields and moderate enantioselectivities (up to 60%).

Selected oxidized fragrance terpenes are common contact allergens

Abstract: Terpenes are widely used fragrance compounds in fine fragrances, but also in domestic and occupational products. Terpenes oxidize easily due to autoxidation on air exposure. Previous studies have shown that limonene, linalool and caryophyllene are not allergenic themselves but readily form allergenic products on air-exposure. This study aimed to determine the frequency and characteristics of allergic reactions to selected oxidized fragrance terpenes other than limonene. In total 1511 consecutive dermatitis patients in 6 European dermatology centres were patch tested with oxidized fragrance terpenes and some oxidation fractions and compounds. Oxidized linalool and its hydroperoxide fraction were found to be common contact allergens. Of the patients tested, 1.3%showed a positive reaction to oxidized linalool and 1.1%to the hydroperoxide fraction. About 0.5%of the patients reacted to oxidized caryophyllene whereas 1 patient reacted to oxidized myrcene. Of the patients reacting to the oxidized terpenes, 58%had fragrance-related contact allergy and/or a positive history for adverse reaction to fragrances. Autoxidation of fragrance terpenes contributes greatly to fragrance allergy, which emphasizes the need of testing with compounds that patients are actually exposed to and not only with the ingredients originally applied in commercial formulations.

Studies on terpenoids produced by actinomycetes. Isolation and structural elucidation of antioxidative agents, naphterpins B and C.

Abstract: As a result of screening for terpenoids produced by Actinomycetes, naphterpins B and C, two new congeners of naphterpin were isolated from Streptomyces sp. CL190 and their structures were determined by NMR spectral analysis.

The first total synthesis of (-)-methyl barbascoate.

Abstract: The neo-trans-clerodane natural product, (−)-methyl barbascoate 1, has been synthesized for the first time starting from the known ketone 6 derived from (R)-(−)-Wieland−Miescher ketone analogue 5.

Essential oils and terpenes

Abstract: Introduction 159 Structural Classification 160 Structure-Activity Relationships 162 Improving Permeation Enhancement Ability of Terpenes 163 Mechanism of Action of Terpenes 165 Terpene Derivatives as Enhancers 168 Conclusions 171 References 171One of the most common approaches to drug penetration enhancement is the use of chemical agents which modify the skin barrier properties. For such an enhancer to be acceptable, the following properties are desired1: It should be nontoxic, nonirritating, exhibit no pharmacological property of its own, exert reversible effects on the skin, and be cosmetically acceptable. While a number of chemicals such as sulfoxides, alcohols, pyrrolidones, fatty acids, Azone have been studied, none of them have been proven to be outstanding often due to safety concerns. Terpenes may offer advantages over such enhancers because of their natural origin as well as Generally Regarded As Safe (GRAS) status. They are carbon, hydrogen, and oxygen containing nonaromatic compounds found in essential oils, extracted from flowers, fruits, and other natural products. These compounds have been used for a long time as fragrances and flavoring agents in commercial preparations (sweets, toothpastes, cigarettes). Table 13.1 provides examples of essential oils which have various terpenes or terpenoids as their main constituents.

Two New Monoterpene Glycosides and Trypanocidal Terpenoids from Dracocephalum kotschyi.

Abstract: From the whole plant of Dracocephalum kotschyi BOISS., two new monoterpene glycosides (9, 10), together with seven known terpenoids and a phytosterol (1—8), were isolated. Their structures were determined to be limonen-10-al (1), geranial (2), neral (3), β-sitosterol (4), oleanolic acid (5), ursolic acid (6), p-mentha-8-en-1,2-diol (7), colosolic acid (8), limonen-10-ol 10-O-β-D-glucopyranoside (9), and limonen-10-ol 10-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranoside (10). Compounds 1 (3.1 μM), 2 (3.1 μM), 3 (3.1 μM), 5 (6.2 μM), 6 (6.2 μM), and 8 (6.2 μM) were effective against epimastigotes of Trypanosoma cruzi.

Biotransformation of terpenes and related compounds by suspension culture of Glycyrrhiza glabra L. (Papilionaceae)

Abstract: Biotransformation of monoterpene aldehydes and related compounds, carvone and bornyl acetate was carried out by cell suspension culture of Glycyrrhiza glabra L. Cells reduced most saturated and unsaturated terpene aldehydes, aromatic and related aldehydes to corresponding primary alcohols. Furthermore, the C=C bonds in the side chain of cinnamaldehyde and in the cyclohexene ring of carvone were converted into corresponding saturated compounds, hydrocinnamylalcohol, cis- and trans-dihydrocarvone. Bornyl acetate hydrolyzed to two isomers, isoborneol and endo-borneol. Copyright © 2004 John Wiley & Sons, Ltd.

Method for the production of flavor-active terpenes

Abstract: Disclosed is a method for producing flavor-active terpenes from terpene hydrocarbons. According to said method, a lyophilized mycel which is first rehydrated and is then mixed with the substrate is used preferably in a submerged culture in the framework of selective biotransformation with the aid of microorganisms. The inventive method, which can be carried out especially in an enantioselective, stereoselective, and/or regioselective manner, makes it possible to obtain terpenoid alcohols, epoxides, aldehydes, ketones, polyalcohols, carbonyls, and carbonyl alcohols with the aid of fusarium, pleutorus, penicillium, and chaetomium species, the obtained substances being isolated particularly from cellular components. Said method should be carried out above all in a stirred tank, surface reactor, or fixed bed reactor while preferably taking place in a two-phase system with reduced carbon source moieties. The obtained flavor-active terpenes are used as flavors and fragrances preferably in the food, cosmetic, and pharmaceutical industry.

Effects of Ammonium Concentration on the Yield, Mineral Content and Active Terpene Components of Chrysanthemum Coronarium L. in a Hydroponic System

Abstract: Chrysanthemum coronarium L. is one of the most important medicinal plants cultivated in East Asia. The objective of this study was to determine the effect of ammonium ion on the yield and effective components of the plant grown in a deep floating technique (DFT) system under greenhouse conditions. Our results indicated that growth characteristics and the dry weight of leaves of C. coronarium L. decreased significantly with increasing ammonium concentration in nutrient solution. The maximum flowerhead yield was achieved in 1.8 mM of ammonium. Contents of sesquiterpene lactones were increased by increasing ammonium concentration, but yields were decreased by ammonium treatment. Maximum yields of sesquiterpene lactones were achieved in 3.1 mM ammonium concentration (r=0.976***). A highly negative correlation (r=-0.804***) was observed between sesquiterpene lactone contents and nitrogen content in the flower part. Essential oil yields decreased with increasing ammonium treatment and a high correlation was observed (r=0.865, p<0.001) between essential oil content and nitrogen content in leaves. terpenes are synthesized from acetyl CoA via the chlorophyll. It also reacts as a cofactor for the mevalonic aicd pathway and are derived from the union of chloroplast ribosome (A 70S), which is responsible 5-carbon elements that have the branched carbon for the biosynthesis of large subunits of ribulose- skeleton of isoprene . The consumption of herbal 1, 5-bisphosphate (RuBP) carboxylase and enzymes that (2) medicine is continuously increasing throughout the world participate in CO fixation . The calcium content in the and many active components have been isolated from plant tissue of basil has a higher correlation with the herbs. The leaves of Chrysanthemum coronarium L. are essential oil terpene concentration than with nitrogen rich in minerals, and the flowerheads have a strong content . Soil application of only phosphate and aromatic odor due to the presence of essential oils, nitrogen plus phosphate fertilizer has reduced the primarily monoterpenoid and sequiterpenoid concentrations of terpenoid lactones in Ginkgo compounds . Bioactive terpenes, such a s seedling . Nitrogen limiting conditions increase volatile (3)

Synthesis and Gelation Properties of N,N′-Bis(3,4,5-trialkoxy)benzoylurea: Terpene and Perfume Gels

Abstract: New organogelator, N,N'-bis(3,4,5-tridodecyloxy)benzoylurea (1), gelled organic liquid such as alcohol, hydrocabons, ethyl acetate, salad oil, terpenes, and essential and perfume oil at low concentration of gelator The terpene and perfume gels show good release of the volatile components for a long time

Antimicrobially Active Terpenes Cause K+ Leakage in E. coli Cells

Abstract: The known antimicrobially active oxygenated terpenes, carvone, terpinen-4-ol, α-terpineol, carveol and myrtenol were found to cause significant K+ leakage from E. coli cells. In contrast, the relatively inactive oxygenated terpenes, 1,8-cineole and p-menth-6-ene-2,8-diol, did not cause significant K+ leakage. Slight structural differences between active terpenes were found to affect the rate of K+ leakage from E. coli cells. The membrane permeabilizing effect of the active terpenes is considered a significant factor in their antimicrobial activity.

Production of volatile terpenes by proliferating shoots and micropropagated plants of Santolina chamaecyparissus L. (cotton lavender)

Abstract: The biosynthetic capacity of in vitro proliferating shoots and regenerated callus clones has been evaluated for essential oil production. On evaluation it was found that the essential oil isolated from foliage of proliferating shoots and regenerated plantlets was a complex mixture with 49 components, 25 of which were identified, corresponding to 80% of the total oil content. The analysis of the identified constituents included monoterpene hydrocarbon (43%), oxygenated monoterpene (31%), sesquiterpene hydrocarbons (7.4%) and oxygenated sesquiterpenes (4.0%). The major constituents were myrcene, limonene, (E)-linalool, (Z)-β-ocimene and β-caryophyllene oxide.

ORGANIC SYNTHESIS AND INDUSTRIAL ORGANIC CHEMISTRY Preparation of High-Melting Polyterpene Resins from -Pinene

Abstract: The AlCl 3 -catalyzed low-temperature polymerization of -pinene in the presence of various activating additives was studied. Polyterpene resins (PTRs) are prepared by acid- catalyzed polymerization in the course of deep proc- essing of turpentine. These resins are widely used in industry, especially beyond Russia. Depending on the composition of the raw materials and preparation pro- cedure, PTRs have different consistency: from viscous liquids to high-melting solids. The wide spectrum of physicochemical properties determines the applica- tions of PTRs. Of most interest are solid high-melting PTRs with the ring-and-ball softening point T s above 90 C (PTR 90 ). Specifically these products, produced mainly in the United States from turpentine enriched in -pinene, are successfully used for more than 30 years as thermoplastic adhesive additives in pro- duction of hot-melt and pressure-sensitive adhesives, and also of paint-and-varnish, sealing, and insulating materials (1 4). In oleoresin and sulfate turpentine produced in Russia, the content of -pinene does not exceed 5%, and the major component is -pinene, from which it is difficult to prepare PTR 90 in a high yield (5 10). This is primarily due to the specific features of the molecular structure of -pinene, in which the double bond, in contrast to -pinene, is sterically shielded, which hinders the polymeric chain propagation. Therefore, the development and choice of the best catalytic systems and conditions for -pinene polymerization, providing high yield of PTR 90 ,i s of considerable theoretical and applied interest. The polymerization of -pinene was studied in the temperature range from 28 to +10 C in the presence of a mixture of Friedel Crafts catalysts (AlCl 3 and SbCl 3 ), and also of heteropoly acids (HPAs) H 3 PW 12 O 40 (PW 12 ) and H 4 SiMo 12 O 40 (SiMo 12 ). As a result, we obtained PTR 90 samples in yields reaching 84%. These samples were solid glassy substances with the color from light yellow to light brown and T s =9 2 115 C (Table 1). The molecular weight (MW) of PTR 90 is 580 800, and the intrinsic viscosity at 20 C, 0.0124 0.0289 dl g 1 . The PTR 90 is a mixture of oligomers of monoterpene hydrocarbons with the chain length from 3 to 6 C 10 H 16 units (so-called poly- terpenes, PTs) and of a small amount of dimers of -pinene and/or other monoterpene hydrocarbons (di- terpenes, DTs). The DT fraction isolated from PTR 90 is a transpar- ent light yellow oily liquid with a kinematic viscosity at 20 C of 130 200 mm 2 s 1 and a density of 936 942 g dm 3 . The boiling point of DT is 150 200 Ca t 0.5 kPa, refractive index n D 1.5126 1.5157, and MW 270 290.

Terpenes from Mikania aff. jeffreyi (Asteraceae)

Abstract: Ten terpenes, three steroids and one flavone have been isolated from the leaves of Mikania aff. jeffreyi, Asteraceae. Among them there are two new kaurane and one new bis-norlabdane diterpene derivatives. The kaur-16-en-18-oic acid, 4-epi-kaurenoic acid, is predominant in the plant leaves. The structures were elucidated by spectroscopic analysis.

Rearranged Vibsane-Type Diterpenes from Viburnum awabuki and Photochemical Reaction of Vibsanin B.

Abstract: Nine new diterpenes, neovibsanin D (1), 7-epi-neovibsanin D (2), 15-O-methylneovibsanin F (3), 14-epi-15-O-methylneovibsanin F (4), 15-O-methyl-18-oxoneovibsanin F (5), 2-O-methylneovibsanin H (6), 2-O-methylneovibsanin I (7), neovibsanin G (8), and 14-epi-neovibsanin G (9), were isolated from a methanol extract of the leaves of Viburnum awabuki. Their structures were elucidated to be uniquely rearranged vibsane-type diterpenes by spectroscopic analyses and comparison of NMR data with those of previously reported vibsane-type diterpenes. In addition, irradiation of vibsanin B (12) in methanol with a high-pressure Hg lump led to the direct formation of neovibsanins A (14) and B (15). These results gave a clue to understanding of the biogenetic interconversion of 11-membered vibsanins into neovibsanins.