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PubMed2003

Upper airway irritation of terpene/ozone oxidation products (TOPS). Dependence on reaction time, relative humidity and initial ozone concentration.

Recently, we reported the formation of unidentified strong upper airway irritants in reaction mixtures of terpenes and ozone. The identified products included aldehydes, ketones and carboxylic acids. Here we report the effects of variation of reaction time, relative humidity and initial ozone concentration on irritant formation in a flow reaction system using R-(+)-limonene and isoprene. Upper airway irritation was measured in mice as reduction of the respiratory rate. For both substances maximum irritation was observed for low humidity (<2% RH)/short time (16-30 s) reaction mixtures, and both moderate humidity ( approximately 32% RH) and longer reaction times (60-90 s) resulted in significantly less irritation. These results suggest that some unidentified intermediates react with water vapor to give less irritating products. Irritation measured at four ozone concentrations (0.5, 1, 2 and 3.5 ppm) using low humidity/short time reaction conditions for limonene (50 ppm) and isoprene (500 ppm) revealed that at 0.5 ppm, irritation was at the same level as that for the pure terpenes, indicating that at 0.5 ppm ozone the combined irritant effect was near the no effect level for the product mixture.

Animals↗
PubMed2004

Effects of including silage in the diet on volatile compound profiles in Montasio cheese and their modification during ripening.

Effects of including silage in the diet on volatile compound profiles and their modification during ripening of Montasio cheeses were examined. Twelve farms were selected and grouped according the type of forage in the ration: hay-based diets (four farms); hay and corn silage-based diets (four farms); and diets based on hay, corn silage and grass silages (four farms). For cheesemaking, 1000 kg of milk collected from two consecutive milkings was sampled from each farm and processed in the same cheese factory. Cheeses were ripened in the same cellar, in controlled humidity (78-85% relative humidity) and temperature (9-12 degrees C), until analysis. After 68 (62-74), 200 (194-206) and 360 (354-366) d of ripening, a cheese from each batch was analysed for moisture, protein and fat, volatile fatty acids (VFA) and volatile compounds. These latter were analysed by dynamic reverse carrier gas headspace gas chromatographic mass spectrometry (GC-MS) technique, scanning from m/z 29 to m/z 300 at 0.5 s cycle time. Total and individual VFA contents of cheeses did not differ between the different dietary treatments and increased linearly (P<0.01) during ripening, indicating that there were no appreciable defects of fermentation. Sixty-two volatile compounds were identified in the cheese samples: 12 aldehydes, 9 ketones, 16 alcohols, 17 esters, 2 hydrocarbons, 4 sulphur-containing compounds and 2 terpenes. Diet significantly affected the amount of total alcohols, ethanol, isobutanol, 1-penten-3-ol, 2-methyl-1-butanol and the sum of all the volatile compounds. Significant variations of 33 volatile compounds (9 aldehydes, 4 ketones, 6 alcohols, 10 esters, 1 hydrocarbons, 2 sulphur containing compounds, and 1 terpene) were observed during ripening. These results suggest that the influence of diet composition on volatile compounds of matured cheeses are related more to effects on microbial and chemical fermentations in cheese during ripening rather than to a direct transfer of molecules from milk.

Alcohols↗
PubMed2006

Impact of humidity on the ozone initiated oxidation of limonene, delta3-carene, and alpha-pinene.

The effect of water on the initial secondary organic aerosol (SOA) formation from gas-phase ozonolysis of limonene, delta3-carene, and alpha-pinene (-3 and approximately 1.5 x 10(11) molecule cm(-3) reacted) has been investigated in a flow reactor at controlled relative humidity (RH), temperature (298 +/- 0.4 K), and reaction time (270 +/- 2 s). Low amounts of terpene converted minimize the impact of secondary reactions. A comparison of the SOA formation from the three terpenes was made for initial rate of reactions being around 7.5 x 10(8) and 15 x 10(8) molecule cm(-3) s(-1). The most efficient species in producing SOA was limonene, while alpha-pinene was the least efficient. The results showed that an enhancement in water vapor concentration (<2-85% RH) caused an increase in both integrated mass (M10-300nm) and total number (N10-300nm). The effect on number and mass were a factor of 2-3 and 4-8, respectively. Physical water up-take can partly explain the increase in mass, but not the observed increase in number. Therefore it was concluded that the increase in water concentration must, by a gas-phase reaction, produce more low volatility product(s).

Air Pollutants↗
PubMed2002

Characterization of essential oils from lamiaceae species by fourier transform Raman spectroscopy.

The Fourier transform Raman (FT-Raman) spectra of pure terpenes and essential oils obtained by hydrodistillation of some Lamiaceae species, are presented. This study shows that principal components of an essential oil can be recognized by FT-Raman. Components predicted by FT-Raman spectrum of an essential oil correlate well with those found as major constituents by GC-MS. In this way the basic chemical character of an essential oil can be recognized. The results demonstrate that certain Raman intensities can be correlated to specific terpenes and therefore FT-Raman can discriminate between the essential oils of which main components belong to different classes of compounds.

Acyclic Monoterpenes↗
PubMed2005

Effect of chitosan on the biological properties of sweet basil (Ocimum basilicum L.).

The effect of the treatment of chitosan at various concentrations (0.01%, 0.05%, 0.1%, 0.5%, and 1%) upon sweet basil (Ocimum basilicum L.) before seeding and transplanting was investigated in aspects of the amount of phenolic and terpenic compounds, antioxidant activity, and growth of the basil, as well as the phenylalanine ammonia lyase (PAL) activity. The total amount of the phenolic and terpenic compounds increased after the chitosan treatment. Especially, the amounts of rosmarinic acid (RA) and eugenol increased 2.5 times and 2 times, respectively, by 0.1% and 0.5% chitosan treatment. Due to the significant induction of phenolic compounds, especially RA, the corresponding antioxidant activity assayed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging test increased at least 3.5-fold. Also, the activity of PAL, a key regulatory enzyme for the phenylpropanoid pathway, increased 32 times by 0.5% chitosan solution. Moreover, after the elicitor chitosan treatment, the growth in terms of the weight and height of the sweet basil significantly increased about 17% and 12%, respectively. Our study demonstrates that an elicitor such as chitosan can effectively induce phytochemicals in plants, which might be another alternative and effective means instead of genetic modification.

Antioxidants↗
PubMed2004

Aroma retention in sol-gel-made silica particles.

The retention performance of aroma molecules from different chemical classes (e.g., alcohols, esters, aldehydes, and terpenes) by silica particles made by hydrolysis of tetraethyl orthosilicate is investigated. Since particle morphology, porosity, and pore size distribution can be controlled by the sol-gel preparation method, the influence of the nanoconfinement in the microporous matrix on aroma retention is studied as well as the effect of the initial aroma load of the particles. As the porosity is decreased, aroma molecules are entrapped more efficiently in the silica particles. The retention performance decreased from alcohols > aldehydes >/= esters > terpenes as with polar organic matrices. Open sol-gel-made silica particles show an increased retention with increasing aroma load, while denser silica matrices show a maximum retention with increasing load.

Alcohols↗
PubMed2006

Isotopic criteria in the characterization of aromatic molecules. 1. Hydrogen affiliation in natural benzenoid/phenylpropanoid molecules.

The site-specific isotope ratios of several families of aromatic molecules are analyzed in terms of hydrogen affiliation and discriminating potential. Among the aromatic molecules produced by plants, many are biosynthesized by the shikimate pathway, but the terpenic pathway also forms some compounds with a benzenic ring. In compounds of the phenylpropanoid family, specific hydrogen connections are determined with cinnamic acid, a key intermediate in the formation of a large number of aromatic molecules. Then affiliations through the phenylalanine precursor, back to the parent d-erythrose 4-phosphate and phosphoenolpyruvate molecules and finally to glucose, are considered. Typical isotopic profiles of the benzenic ring in natural, as compared to non-natural, molecules are defined. The dispersion observed in the (D/H)i ratios of the lateral chains is illustrative of diverse mechanistic responses and the role of exchange phenomena. The isotopic patterns of aromatic molecules pertaining to the terpenic family are drastically different from those of the shikimate descendants, and they exhibit much less variability. They enable the stereochemical affiliation of individual hydrogen atoms to be traced back first to the parent atoms in the common intermediate, geranyl diphosphate, then to the glyceraldehyde 3-phosphate and pyruvate couple involved in the DOXP pathway, and ultimately to the glucose precursor. The results illustrate the aptitude of the site-specific isotope ratios not only to authenticate natural with respect to chemical molecules but also to characterize different metabolic pathways and to reveal differences associated with the nature of the plant precursor.

Benzene↗
PubMed2003

Exploring sponge-derived terpenoids for their potency and selectivity against 12-human, 15-human, and 15-soybean lipoxygenases.

To sharpen the search for new lipoxygenase inhibitors, we designed a screen to probe for both potency and selectivity. The assay utilized 12-human (12-HLO), 15-human (15-HLO), and 15-soybean (15-SLO) lipoxygenases. The IC(50) value data obtained provided new insights about structure-activity relationships (SAR) for redox and nonredox inhibitors. All of the compounds tested were isolated from sponges and consisted of a novel terpenoid, hyrtenone A (1), and 12 known terpenoids. Potent compounds were defined as those having IC(50) values < 1 microM, and selectivity was assessed from the three possible IC(50) value ratios. One of the four terpenoid redox inhibitors studied, puupehenone (2), was equivalent to or better in potency than the well-known redox inhibitor nordihydroguarierate acid (NDGA, 14). However, none of the terpene redox inhibitors exhibited a selectivity ratio on a par with that of 14. Several potent nonredox inhibitors were identified, and one, dimethoxypuupehenol (5), exhibited notable selectivity. The structural elucidation of 1 and the SAR results for 13 natural products are reported. This study suggests that sponge-derived terpenes are a promising source for new lipoxygenase inhibitors.

Animals↗
PubMed2006

C35 terpenoids from the bark of Calocedrus macrolepis var. formosana with activity against human cancer cell lines.

Ferrugicadinol (1) and ferrugieudesmol (2), two new compounds with a unique C35 terpene skeleton, were isolated from the bark of Calocedrus macrolepis var. formosana. Their structures were elucidated principally from spectroscopic evidence. The two new C35 terpenes showed cytotoxicity against human oral epidermoid carcinoma KB cells with IC50 values ranging from 11 to 14 microM.

Antineoplastic Agents, Phytogenic↗
PubMed2004

Antiherbivore chemistry of Eucalyptus-cues and deterrents for marsupial folivores.

Formylated phloroglucinol compounds (FPCs) are the single most important factor determining the amount of foliage that marsupial folivores eat from individual Eucalyptus trees. Folivores need to recognize which trees contain FPCs if they are to avoid them and forage efficiently, they are challenged by great diversity in the types and quantities of FPCs present, even within eucalypt species. We investigated the relationship between FPCs and terpenoids in species with both simple and complex FPC profiles and found strong positive correlations between terpenes generally, and several monoterpenes in particular, and FPCs. Terpene cues also indicated qualitative differences in trees' FPC profiles. We describe significant qualitative and quantitative variation in FPCs in several species that are important food sources for marsupial folivores. New discoveries include the fact that macrocarpals occur as two major, distinct groups and several new dimeric acylphloroglucinols from Eucalyptus strzeleckii. These patterns add to the chemical complexity of the foraging environment for folivores.

Animals↗
PubMed1993

Quality of Ginkgo preparations.

A survey of known and of recently isolated constituents from Ginkgo leaves is given. The structures of flavonoids and terpene lactones which are considered to be the active compounds as well as their qualitative and quantitative determination in Ginkgo leaves and phytomedicines are presented. In the case of flavonoid analysis three selective methods worked out in our laboratories are described. The quality control of terpene lactones is discussed on the basis of a recently published paper. Finally, the standardization methods used for the quality control of Ginkgo preparations as well as the question as to whether or not phytomedicine generics--so called "phytogenerics"--exist, is discussed.

Carbohydrate Sequence↗
PubMed1990

Growth, terpenoid production and antibacterial activity of an in vitro culture of the liverwort Fossombronia pusilla.

In vitro cultures of the liverwort, Fossombronia pusilla, have been ititiated from spores. They grew well on Gamborg B5 medium supplemented with 2% saccharose and 12.5 micrograms/l vitamin B12. Undifferentiated cultures were obtained on Knop mineral solution with 4% glucose. The cultures produced the same constituents as collected material. Perrottetianal A and B, known substances from liverworts were isolated and characterized by spectroscopic methods as well as alpha-(-)-santonin. A hitherto unknown diterpene dialdehyde-8-hydroxy-9-hydroperrottetianal A--could also be characterized. Furthermore, 7 terpenes were identified by GC/MS. A petrol ether extract and the isolated terpenes exerted antibacterial activity.

Anti-Infective Agents↗
PubMed2003

Respiratory symptoms and occupational exposures in New Zealand plywood mill workers.

OBJECTIVES: To study work exposure and respiratory symptoms in New Zealand plywood mill workers. METHODS: Personal inhalable dust (n = 57), bacterial endotoxin (n = 20), abietic acid (n = 20), terpene (n = 20) and formaldehyde (n = 22) measurements were taken and a respiratory health questionnaire was administered to 112 plywood mill workers. RESULTS: Twenty-six percent of the dust exposures exceeded 1 mg/m(3), however, none of the samples exceeded the legal limit of 5 mg/m(3) [geometric mean (GM) = 0.7 mg/m(3), geometric standard deviation (GSD) = 1.9]. Workers in the composer area (where broken sheets are joined together) were significantly (P < 0.01) more highly exposed. Endotoxin levels were low to moderate (GM = 23.0 EU/m(3), GSD = 2.8). Abietic acid levels ranged from 0.3 to 2.4 micro g/m(3) (GM = 0.7 micro g/m(3), GSD = 1.8) and were significantly (P < 0.05) higher for workers in the composer area of the process. Geometric mean levels of alpha-pinene, beta-pinene and Delta(3)-carene were 1.0 (GSD = 2.7), 1.5 (GSD = 2.8) and 0.1 (GSD = 1.4), respectively, and alpha-pinene and beta-pinene levels were significantly (P < 0.001) higher for workers in the 'green end' of the process, up to and including the veneer dryers. Formaldehyde levels ranged from 0.01 to 0.74 mg/m(3) [GM = 0.08 mg/m(3) (= 0.06 p.p.m.), GSD = 3.0]. Asthma symptoms were more common in plywood mill workers (20.5%, n = 112) than in the general population [12.8%, n = 415, adjusted OR (95% CI) = 1.5 (0.9-2.8)]. Asthma symptoms were associated with duration of employment and were reported to lessen or disappear during holidays. No clear association with any of the measured exposures was found, with the exception of formaldehyde, where workers with high exposure reported more asthma symptoms (36.4%) than low exposed workers [7.9%, adjusted OR (95% CI) = 4.3 (0.7-27.7)]. CONCLUSIONS: Plywood mill workers are exposed to inhalable dust, bacterial endotoxin, abietic acid, terpenes and formaldehyde, and they appear to have an increased risk of developing work-related respiratory symptoms. These symptoms may be due to formaldehyde exposure, although a potential causal role for other exposures cannot be excluded.

Abietanes↗
PubMed2005

Utilization of geraniol is dependent on molybdenum in Pseudomonas aeruginosa: evidence for different metabolic routes for oxidation of geraniol and citronellol.

Mini-Tn5-induced mutants with defects in utilization of linear terpenes such as citronellol, geraniol, citronellate and/or geranylate were isolated from Pseudomonas aeruginosa. One mutant was unable to utilize geraniol but showed wild-type growth with the three other acyclic terpenes tested. The Tn5 insertion site of the mutant was determined by DNA sequencing. Comparison with the P. aeruginosa genome sequence revealed that PA3028, an ORF with high similarity on the amino acid level to molybdenum cofactor biosynthesis protein A2 (encoded by moeA2), was the target of mini-Tn5 in the mutant. Disruption of moeA2 in P. aeruginosa PAO1 wild-type by insertion mutagenesis resulted in the same geraniol-minus phenotype. The ability to utilize geraniol was restored to the mutant by conjugative transfer of PCR-cloned wild-type moeA2 on a broad-host-range plasmid. Growth of P. aeruginosa PAO1 on geraniol and geranial, but not on citronellol, citronellate or geranylate, was inhibited by the presence of 10 mM tungstate, a molybdenum-specific inhibitor. Inhibition by tungstate was prevented by addition of molybdate. The results indicate that at least one step in the oxidation of geraniol to geranic acid (geranial oxidation) is a molybdenum-dependent reaction in P. aeruginosa and is different from the molybdenum-independent oxidation of citronellol to citronellate.

Acyclic Monoterpenes↗
PubMed1985

Oxidation of acyclic terpenoids by Corynebacterium sp.

Squalene analogs such as lycopersene, geranylfarnesyl, digeranyl, and 2-hydroxy-2,3-dihydrosqualene and terpene alcohol derivatives such as farnesyl benzyl ether, farnesyl pivalate, geranylgeranyl pivalate, geranyl pivalate, and geranyl benzyl ether were oxidized by Corynebacterium sp. strain SY-79, which was isolated from soil by using squalene as a carbon source. Lycopersene and geranylfarnesyl gave no major product. Digeranyl, geranyl benzyl ether, and geranyl pivalate gave terminal oxidation products, and 2-hydroxy-2,3-dihydrosqualene, farnesyl benzyl ether, farnesyl pivalate, and geranylgeranyl pivalate were degraded to give lower molecular carboxylic acids. Strain SY-79 showed promising oxidative activities toward acyclic terpenes, although the metabolites obtained were variable, depending upon the structure of the substrate.

Corynebacterium↗
PubMed1990

Volatile metabolites and other indicators of Penicillium aurantiogriseum growth on different substrates.

Penicillium aurantiogriseum Dierckx was cultivated on six agar substrates (barley meal agar, oat meal agar, wheat meal agar, malt extract agar, Czapek agar, and Norkrans agar) and on oat grain for 5 days in cultivation vessels provided with an inlet and an outlet for air. Volatile metabolites produced by the cultures were collected on a porous polymer adsorbent by passing an airstream through the vessel. Volatile metabolites were collected between days 2 and 5 after inoculation. CO2 production was simultaneously measured, and after the cultivation period ergosterol contents and the numbers of CFU of the cultures were determined. Alcohols of low molecular weight and sesquiterpenes were the dominant compounds found. During growth on oat grain the production of 8-carbon alcohols and 3-methyl-1-butanol was higher and the production of terpenes was lower than during growth on agar substrates. The compositions of the volatile metabolites from oat grain were more similar to those from wheat grain, which was used as a substrate in a previous investigation, than to those produced on any of the agar substrates. Regarding the agar substrates, the production of terpenes was most pronounced on the artificial substrates (Czapek agar and Norkrans agar) whereas alcohol production was highest on substrates based on cereals. The production of volatile metabolites was highly correlated with the production of CO2 and moderately correlated with ergosterol contents, whereas no correlation with the numbers of CFU was found. Thus, the volatile metabolites formed and the ergosterol contents of fungal cultures should be good indicators of present and past fungal activity.

Alcohols↗
PubMed2003

Iontophoretic transdermal delivery of buspirone hydrochloride in hairless mouse skin.

The transdermal delivery of buspirone hydrochloride across hairless mouse skin and the combined effect of iontophoresis and terpene enhancers were evaluated in vitro using Franz diffusion cells. Iontophoretic delivery was optimized by evaluating the effect of drug concentration, current density, and pH of the vehicle solution. Increasing the current density from 0.05 to 0.1 mA/cm2 resulted in doubling of the iontophoretic flux of buspirone hydrochloride, while increasing drug concentration from 1% to 2% had no effect on flux. Using phosphate buffer to adjust the pH of the drug solution decreased the buspirone hydrochloride iontophoretic flux relative to water solutions. Incorporating buspirone hydrochloride into ethanol:water (50:50 vol/vol) based gel formulations using carboxymethylcellulose and hydroxypropylmethylcellulose had no effect on iontophoretic delivery. Incorporation of three terpene enhancers (menthol, cineole, and terpineol) into the gel resulted in a synergistic effect when combined with iontophoresis. Menthol was the most active enhancer, and when combined with iontophoresis it was possible to deliver 10 mg/cm2/day of buspirone hydrochloride.

Administration, Cutaneous↗
PubMedDate not supplied

Foliar and cortex oleoresin variability of silver fir (Abies alba Mill.) in Albania.

Terpene composition of needle and cortical oleoresin from lateral shoots were analyzed by GC/MS for four Silver fir (Abies alba Mill.) populations scattered in natural species range in Albania. More than sixty compounds were detected in the needle oleoresin, which was characterized by a high content of alpha-pinene, camphene, beta-pinene, limonene and bornyl acetate. Three monoterpenes, alpha-pinene, beta-pinene and limonene, and two sesquiterpenes, beta-caryophyllene and germacrene D, comprised the majority of cortical oleoresin. The terpene composition differences among the populations that led to the recognition of two chemotypes. The needle oleoresin from the provinces of Puka, Bulqiza and Llogara were characterised by high amounts of beta-pinene, camphene and alpha-pinene and low amounts of limonene, while that from Drenova had high amounts of beta-pinene and limonene. A similar pattern was found in the cortical oleoresin with the exception of camphene that was a minor contributor. Geographical and seasonal variation between the populations was, also, investigated. Multivariate analysis of both needle and cortical oleoresin separated Drenova (southeastern population) from the other sites. When both major monoterpenes and sesquiterpenes were considered four chemical profiles could be attributed. Based on their chemical profiles, the populations can be divided into two groups: Populations with high content of beta-pinene and alpha-pinene but a low content of limonene (Puka, Bulqiza and Llogara), typical of most of A. alba populations in all its distribution range. Population with a high content of limonene and a moderate content of beta-pinene and alpha-pinene (Drenova).

Albania↗