Artículos de revistas: "Monoterpenic compounds"

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Singh, Vijender, Deepti Katiyar y Mohammed Ali. "Comparative study of volatile constituents and antimicrobial activities of leaves and fruit peels of Citrus sinensis Linn." Journal of Phytopharmacology 4, n.º 2 (25 de abril de 2015): 102–5. http://dx.doi.org/10.31254/phyto.2015.4208.

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A steam distilled volatile oil from the fresh leaves of Citrus sinensis Linn. analysed by capillary-GC and GCMS yielded eight components, of which seven were monoterpenic (99.6%) and one ester (0.4%). Cis-sabinene hydrate (35.1%) was the predominant monoterpene, followed by l - limonene (30.1%), citral (27.9%), lavendulol (2.5%), perillaldehyde (2.0%), α-pinene (1.4%) and perillyl alcohol (0.6%). The ester obtained was tert.-butyl benzoate (0.4%). Whereas volatile oil from its fresh fruit peels yielded five components of which three were monoterpenes (76.5%) and remaining two were non-terpenic compounds. α-pinene (60.80%) was the predominant monoterpene, followed by verbenone (15.40%) and α-thujene (0.30%).The non-terpenic compounds obtained was N-pentylcyclopentane (11.80%) and cyclopentenyl ethyne (11.70%). The maximum antibacterial activity was shown with 1%v/v of volatile oil collected from Greater Noida, U.P on Staphylococcus aureus (16.4 mm) followed by Escherichia coli (14.2 mm), and maximum anti-fungal activity was shown on Candida albicans (13.1 mm) followed by Aspergillus niger (12.5 mm).

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Oliveira, J. M., P. Oliveira, R. L. Baumes y M. O. Maia. "Volatile and Glycosidically Bound Composition of Loureiro and Alvarinho Wines". Food Science and Technology International 14, n.º 4 (agosto de 2008): 341–53. http://dx.doi.org/10.1177/1082013208097442.

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Composition of Loureiro and Alvarinho wines from the Vinhos Verdes region, regarding free volatile compounds as well as glycosidically bound aroma precursors, was exhaustively determined by gas chromatography—mass spectrometry after adsorption on XAD-2 resin. On the whole, were identified and quantified 120 volatile compounds in the free fraction and 77 glycosidically bound compounds, belonging to C6-compounds, alcohols, fatty acids ethyl esters, esters of organic acids, acetates, monoterpenic alcohols, monoterpenic oxides and diols, C13-norisoprenoids, volatile phenols, volatile fatty acids, and carbonyl compounds. Globally, the wines of the two cultivars present similar composition on volatiles. However, regarding varietal compounds, Loureiro wines were richer than Alvarinho ones with respect to C6-compounds and monoterpenic compounds, occurring the opposite for volatile phenols. It was also demonstrated that wines of both varieties might benefit the aroma reserve, present as glycoconjugates, as it is susceptible of being technologically explored. Linalool, Ho-trienol, (α-terpineol, contributing with fruity and floral notes, and (β-damascenone mostly for Alvarinho, confering tropical fruit notes, are the varietal compounds which may particularly influence the aroma of these wines. Respecting fermentative compounds, Alvarinho is also particularly rich in fatty acids ethyl esters related to lipid metabolism and acetates of fusel alcohols, which can provide it a fruity character; Loureiro contains higher levels of esters of organic acids and 2-phenylethanol, conferring fruity and floral notes. Sensory analysis agreed with chemical analyses showing a pronounced tree and tropical fruit character for Alvarinho wines while Loureiro wines present more intense citrus fruit notes.

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Dvořáková, Marcela, Irena Valterová y Tomáš Vaněk. "Biotransformation of a Monoterpene Mixture by in vitro Cultures of Selected Conifer Species". Natural Product Communications 2, n.º 3 (marzo de 2007): 1934578X0700200. http://dx.doi.org/10.1177/1934578x0700200302.

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Biotransformation of monoterpenes is a mild and promising method for the production of stereospecific and regiospecific organic compounds. It is advantageous, especially for the preparation of substances with complicated structures and for those that need to be classed as “natural products“. Our study has focused on the biotransformation of a monoterpenic mixture, turpentine, by Picea abies and Taxus baccata suspension cultures. We identified the biotransformation products and compared the metabolite compositions of the tissue cultures. The major biotransformation products of turpentine were trans-pinocarveol, trans-verbenol, verbenone, myrtenol, α-terpineol and trans-sobrerol, which correspond with the products of biotransformation of the individual monoterpenes, α-pinene and β-pinene, by P. abies suspension culture.

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4

Martins, Cátia, Tiago Brandão, Adelaide Almeida y Sílvia M. Rocha. "Enlarging Knowledge on Lager Beer Volatile Metabolites Using Multidimensional Gas Chromatography". Foods 9, n.º 9 (11 de septiembre de 2020): 1276. http://dx.doi.org/10.3390/foods9091276.

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Foodomics, emergent field of metabolomics, has been applied to study food system processes, and it may be useful to understand sensorial food properties, among others, through foods metabolites profiling. Thus, as beer volatile components represent the major contributors for beer overall and peculiar aroma properties, this work intends to perform an in-depth profiling of lager beer volatile metabolites and to generate new data that may contribute for molecules’ identification, by using multidimensional gas chromatography. A set of lager beers were used as case-study, and 329 volatile metabolites were determined, distributed over 8 chemical families: acids, alcohols, esters, monoterpenic compounds, norisoprenoids, sesquiterpenic compounds, sulfur compounds, and volatile phenols. From these, 96 compounds are reported for the first time in the lager beer volatile composition. Around half of them were common to all beers under study. Clustering analysis allowed a beer typing according to production system: macro- and microbrewer beers. Monoterpenic and sesquiterpenic compounds were the chemical families that showed wide range of chemical structures, which may contribute for the samples’ peculiar aroma characteristics. In summary, as far as we know, this study presents the most in-depth lager beer volatile composition, which may be further used in several approaches, namely, in beer quality control, monitoring brewing steps, raw materials composition, among others.

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Sousa, Carla, Branca M. Silva, Paula B. Andrade, Patrícia Valentão, Artur Silva, Federico Ferreres, Rosa M. Seabra y Margarida A. Ferreira. "Homo-monoterpenic compounds as chemical markers for Cydonia oblonga Miller". Food Chemistry 100, n.º 1 (enero de 2007): 331–38. http://dx.doi.org/10.1016/j.foodchem.2005.09.055.

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Lukić, Igor, Silvia Carlin y Urska Vrhovsek. "Comprehensive 2D Gas Chromatography with TOF-MS Detection Confirms the Matchless Discriminatory Power of Monoterpenes and Provides In-Depth Volatile Profile Information for Highly Efficient White Wine Varietal Differentiation". Foods 9, n.º 12 (2 de diciembre de 2020): 1787. http://dx.doi.org/10.3390/foods9121787.

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To differentiate white wines from Croatian indigenous varieties, volatile aroma compounds were isolated by headspace solid-phase microextraction (HS-SPME) and analyzed by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOF-MS) and conventional one-dimensional GC-MS. The data obtained were subjected to uni- and multivariate statistical analysis. The extra separation ability of the GC×GC second dimension provided additional in-depth volatile profile information, with more than 1000 compounds detected, while 350 were identified or tentatively identified in total by both techniques, which allowed highly efficient differentiation. A hundred and sixty one compounds in total were significantly different across monovarietal wines. Monoterpenic compounds, especially α-terpineol, followed by limonene and linalool, emerged as the most powerful differentiators, although particular compounds from other chemical classes were also shown to have notable discriminating ability. In general, Škrlet wine was the most abundant in monoterpenes, Malvazija istarska was dominant in terms of fermentation esters concentration, Pošip contained the highest levels of particular C13-norisoprenoids, benzenoids, acetates, and sulfur containing compounds, Kraljevina was characterized by the highest concentration of a tentatively identified terpene γ-dehydro-ar-himachalene, while Maraština wine did not have specific unambiguous markers. The presented approach could be practically applied to improve defining, understanding, managing, and marketing varietal typicity of monovarietal wines.

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Hierro, I., A. Valero, P. Pérez, P. González, M. M. Cabo, M. P. Montilla y M. C. Navarro. "Action of different monoterpenic compounds against Anisakis simplex s.l. L3 larvae". Phytomedicine 11, n.º 1 (enero de 2004): 77–82. http://dx.doi.org/10.1078/0944-7113-00375.

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Anikeev, V. I., A. Ermakova, A. M. Chibiryaev y I. V. Kozhevnikov. "Kinetics of thermal conversions of monoterpenic compounds in supercritical lower alcohols". Kinetics and Catalysis 51, n.º 2 (marzo de 2010): 162–93. http://dx.doi.org/10.1134/s0023158410020035.

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9

Danielli, Letícia, Tiago de Souza, Ana Maciel, Marco Ferrão, Alexandre Fuentefria y Miriam Apel. "Influence of Monoterpenes in Biological Activities of Nectandra megapotamica (Spreng.) Mez Essential Oils". Biomolecules 9, n.º 3 (21 de marzo de 2019): 112. http://dx.doi.org/10.3390/biom9030112.

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Investigating the influence of seasonal variations on biological activities is important for pharmacological studies and metabolic engineering. Therefore, this study was conducted to determine the variation of the chemical composition of essential oils obtained from Nectandra megapotamica leaves, collected at different stages of plant development, as well as its influence on the biological activities. A total of 38 compounds were identified that accounted for 97–99.2% of the chemical composition of the oils. Major differences were observed in the monoterpenic fraction, representing 5.1% of the compounds identified in the productive rest phase to 37.1% in the blooming phase. Bicyclogermacrene and germacrene D were the predominant compounds identified in the oil of all collections. Furthermore, limonene, β-pinene, and spathulenol were identified predominantly in the samples of blooming and fruiting phases. The oils exhibited significant antichemotactic activity and different effects in scavenging the radical 2,2-diphenyl-1-picrylhydrazyl. Variations were also observed in the antifungal activity, with the minimum inhibitory concentrations ranging from 125 to 500 μg/mL. These results demonstrate the influence of monoterpenes, primarily limonene, α-pinene, and β-pinene, on the bioactivities of the oil. Studies investigating the variations in the chemical composition of essential oil may offer a strategy to produce a compound or a group of compounds of interest to industries with a specific pharmacological focus.

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Karabaeva, Ra"no Botirovna, Alidzhan Aminovich Ibragimov y Otabek Mamadaliyevich Nazarov. "COMPONENT COMPOSITION OF ESSENTIAL OIL PRUNUS PERSICA VAR. NECTARINA GROWING IN UZBEKI-STAN". chemistry of plant raw material, n.º 4 (21 de diciembre de 2020): 165–70. http://dx.doi.org/10.14258/jcprm.2020046542.

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The article presents the results of determining the composition of essential oils of Prunus persica var. nectarina varieties "yellow nectarine" – "sariк luchchak (uzb.) ", growing in two regions of the Ferghana region of the Republic of Uzbekistan. The pale yellow essential oil was obtained by hydrodistillation from un-dried fresh leaves of plants. The oil composition was determined by chromatography-mass spectrometry on an Agilent 7890 AGC 6890 N gas chromotograph with a quadrupole mass spectrometer (Agilent 5975C inert MSD) as a detector on an HP-5 MS quartz capillary column. An essential oil of pale yellow color was isolated from the leaves of plants. In the composition of essential oils, 56 and 61 compounds were identified in the first and second samples, respectively, wich is 94.55 and 96.00% of the total components. The dominant components of the first saple are camphor bicyclic monoterpene ketones (24.21%), α-thujone (15.00%) and β-thujone (4.27%), aromatic aldehyde benzaldehyde (18.83%) and isobornoleol bicyclic monoterpene alcohol (6.17%). In the second sample, bicyclic monoterpenic ketones (camphor) (36.67%), α-thujone (21.81%) and β-thujone (7.06%) and bicyclic monoterpene alcohol isobornoleol (9.4%) predominate and monocyclic unsaturated monoterpene α-terpinene (2.18%). In both samples, (+)-2-bornanone (camphor) is predominant. The studied variety Prunus persica var. nectarina can serve as a raw material for the production of essential oil, the main components of which are camphor and isobornoleol.

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Ustimenko, Valery Nikolayevich y Gennadiy Vasilyevich Khodakov. "RESEARCHING THE CONNATURAL MONOTERPENIC HYDROCARBONS BIOSYNTHESIS DYNAMICS APPLYING THE KINETIC MODEL AND THE STATE SPACE MODEL". Plant Biology and Horticulture: theory, innovation, n.º 151 (30 de diciembre de 2019): 94–108. http://dx.doi.org/10.36305/2019-2-151-94-108.

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To investigate in succession the dynamics of monoterpenic hydrocarbons biosynthesis in plants of genus Artemisia the algorithm, which connects the intermediates analysis of results after each stage processes and the comparison of theoretical conclusions with new experimental data is developed in this article. It is proved that the uniform kinetic model of chemical essential compounds transformations in a stream from the glucose, mevalonate and isoprene to monoterpenes developed by authors is universal kinetics model in order to explain the connatural biosynthesis of monoterpenes in any ethereous carrier plants. There are founded some kinetic (by specific velocities of biochemical stages of metamorphosis) and a balance sheet (by rations between ring closure degrees) relations during the monoterpenes connatural biosynthesis corresponding to the vegetative phases. The state space model (SSM) for open nonlinear biochemical system is compounded. In this model macroscopic metamorphosis of essential substances is introduced as the sequence of vector's micro-alterations (or a velocity of the modification of a system's biochemical composition) in a orthogonal system of co-ordinates. At the application of the model to substantiate with the theory of a kinetic chemo-systematics, which becomes clear correlations between plants-producers is offered. The biochemical substantiation of individual distinctive indications between plants of genus Artemisia for seven types is introduced, such as: A.abrotanum, A.annua, A.dracunculus, A.glauca, A.scoparia (two c hemostrains) and A.taurica. The mathematical model of molecular-and-phylogenetic exposition of the relationship in a flora based on the example of genus Artemisia is compounded. The influence of environmental factors on kinetic parameters of monoterpenes biosynthesis in plants of the genus A.scoparia from different regions of their growth by means of comparative graph-analytic and matrix analyses of their accumulation dynamics in plants by own results of the experiment and the literary data with the made by authors modeling calculations is proved. The possibility to combine the systematization of plants based on morph-anatomic principles and chemo-regular principles based on the kinetic particularities of monoterpenes biosynthesis during the chemo-phases in vegetative taxons is shown.

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12

Coelho, Eduardo, Margarida Lemos, Zlatina Genisheva, Lucília Domingues, Mar Vilanova y José M. Oliveira. "Validation of a LLME/GC-MS Methodology for Quantification of Volatile Compounds in Fermented Beverages". Molecules 25, n.º 3 (31 de enero de 2020): 621. http://dx.doi.org/10.3390/molecules25030621.

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Knowledge of composition of beverages volatile fraction is essential for understanding their sensory attributes. Analysis of volatile compounds predominantly resorts to gas chromatography coupled with mass spectrometry (GC-MS). Often a previous concentration step is required to quantify compounds found at low concentrations. This work presents a liquid-liquid microextraction method combined with GC-MS (LLME/GC-MS) for the analysis of compounds in fermented beverages and spirits. The method was validated for a set of compounds typically found in fermented beverages comprising alcohols, esters, volatile phenols, and monoterpenic alcohols. The key requirements for validity were observed, namely linearity, sensitivity in the studied range, accuracy, and precision within the required parameters. Robustness of the method was also evaluated with satisfactory results. Thus, the proposed LLME/GC-MS method may be a useful tool for the analysis of several fermented beverages, which is easily implementable in a laboratory equipped with a GC-MS.

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Miladi, Hanene, Rihab Ben Slama, Donia Mili, Sami Zouari, Amina Bakhrouf y Emna Ammar. "Chemical Composition and Cytotoxic and Antioxidant Activities ofSatureja montanaL. Essential Oil and Its Antibacterial Potential againstSalmonellaSpp. Strains". Journal of Chemistry 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/275698.

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The present study describes chemical composition as well as cytotoxic, antioxidant, and antimicrobial activities of winter savorySatureja montanaL. essential oil (EO). The plant was collected from south France mountain, and its EO was extracted by hydrodistillation (HD) and analysed by gas chromatography/mass spectrometry (GC/MS). Thirty-two compounds were identified accounting for 99.85% of the total oil, where oxygenated monoterpenes constituted the main chemical class (59.11%). The oil was dominated by carvacrol (53.35%),γ-terpinene (13.54%), and the monoterpenic hydrocarbonsp-cymene (13.03%). Moreover,S. montanaL. EO exhibited high antibacterial activities with strong effectiveness against several pathogenic food isolatedSalmonellaspp. includingS. enteritidiswith a diameter of inhibition zones growth ranging from 21 to 51 mm and MIC and MBC values ranging from 0.39–1.56 mg/mL to 0.39–3.12 mg/mL, respectively. Furthermore, theS. montanaL. EO was investigated for its cytotoxic and antioxidant activities. The results revealed a significant cytotoxic effect ofS. montanaL. EO against A549 cell line and an important antioxidant activity. These findings suggest thatS. montanaL. EO may be considered as an interesting source of components used as potent agents in food preservation and for therapeutic or nutraceutical industries.

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Wasim, Ahmad, A. Ali, M. Ali, S. R. Mir, S. M. A. Zaidi y Ahmad Sayeed. "NEW FATTY ACID AND AROMATIC MONOTERPENIC ESTERS FROM THE LEAVES OF DIDYMOCARPUS PEDICELLATA R. BR." INDIAN DRUGS 54, n.º 11 (28 de noviembre de 2017): 28–32. http://dx.doi.org/10.53879/id.54.11.11075.

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Didymocarpus pedicellata R. Br. (Gesneriaceae) is a small herb growing in the subtropical Himalayas. It is used to treat kidney diseases, diabetes, diarrhoea, chest pain, cough, epilepsy, heart diseases, stomachache, splenitis, syphilis, wound and ulcer in traditional systems of herbal medicine. It is a major ingredient in polyherbal formulations such as Cystone and Safoof-e-Pathar Phori, which are prescribed to treat kidney and bladder stones. Chromatographic separation of methanolic extract of leaves yielded a new fatty acid ester characterized as n-heneicosanyl linolenate (1), and new aromatic monoterpenic esters identified as 3α-hydroxygeranilanyl-10-benzoate (2), geranilanyl-10-benzoate (3) and geranilanyl- 10-phthalate (4) for the first time in D. pedicellata. The structures of isolated compounds were elucidated on the basis of spectral data analysis and chemical means. The current study has enhanced the phytochemical nature of the plant. The isolated compounds may be used as chromatographic markers for standardization and quality control of crude D. pedicellata leaves and its marketed formulations.

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Foudil-Cherif, Y., B. Y. Meklati, L. Mondello, G. Zappia y G. Dugo. "Enantiomeric Distribution of Five Monoterpenic Compounds in Nine AlgerianEucalyptusEssential Oils by Direct Multidimensional Gas Chromatography". Journal of Essential Oil Research 15, n.º 1 (enero de 2003): 1–5. http://dx.doi.org/10.1080/10412905.2003.9712246.

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Oliveira, José M., Isabel M. Araújo, Óscar M. Pereira, José S. Maia, António J. Amaral y M. Odete Maia. "Characterization and differentiation of five “Vinhos Verdes” grape varieties on the basis of monoterpenic compounds". Analytica Chimica Acta 513, n.º 1 (junio de 2004): 269–75. http://dx.doi.org/10.1016/j.aca.2003.10.020.

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Garzoli, Stefania, Valentina Vaglia, Marcello Iriti y Sara Vitalini. "Vapor and Liquid Phase Profiles of Essential Oils from Abies, Picea and Pinus Species and Their Phytotoxic Interactions with Weed Growth in Pre- and Post-Emergence Conditions". Plants 12, n.º 5 (3 de marzo de 2023): 1172. http://dx.doi.org/10.3390/plants12051172.

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The chemical content of essential oils (EO) obtained from the leaves of four Pinaceae (Abies alba, Picea abies, Pinus cembra and Pinus mugo) was investigated by SPME-GC-MS technique. The vapor phase was characterized by the monoterpenes with values higher than 95.0%. Among them, α-pinene (24.7–48.5%), limonene (17.2–33.1%) and β-myrcene (9.2–27.8%) were the most abundant. The monoterpenic fraction prevailed over the sesquiterpenic one (≥74.7%) in the EO liquid phase. Limonene was the major compound in A. alba (30.4%), P. abies (20.3%) and P. mugo (78.5%), while α-pinene in P. cembra (36.2%). Regarding the phytotoxic properties, EOs were studied at different doses (2–100 μL) and concentrations (2–20/100 μL/mL). All EOs were found to be significantly active (p-value ˂ 0.05) against the two recipient species in a dose-dependent way. In pre-emergence tests, germination of Lolium multiflorum and Sinapis alba was reduced by up to 62–66% and 65–82%, respectively, as well as their growth by up to 60–74% and 65–67%, due to the effects of compounds in both the vapor and liquid phases. In post-emergence conditions, at the highest concentration, the phytotoxicity of EOs caused heavy symptoms and, in the case of S. alba, A. alba EO completely destroyed (100%) the treated seedlings.

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Alves-Silva, Jorge M., Mónica Zuzarte, Henrique Girão y Lígia Salgueiro. "The Role of Essential Oils and Their Main Compounds in the Management of Cardiovascular Disease Risk Factors". Molecules 26, n.º 12 (9 de junio de 2021): 3506. http://dx.doi.org/10.3390/molecules26123506.

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Cardiovascular diseases (CVDs) are a global health burden that greatly impact patient quality of life and account for a huge number of deaths worldwide. Despite current therapies, several side effects have been reported that compromise patient adherence; thus, affecting therapeutic benefits. In this context, plant metabolites, namely volatile extracts and compounds, have emerged as promising therapeutic agents. Indeed, these compounds, in addition to having beneficial bioactivities, are generally more amenable and present less side effects, allowing better patient tolerance. The present review is an updated compilation of the studies carried out in the last 20 years on the beneficial potential of essential oils, and their compounds, against major risk factors of CVDs. Overall, these metabolites show beneficial potential through a direct effect on these risk factors, namely hypertension, dyslipidemia and diabetes, or by acting on related targets, or exerting general cellular protection. In general, monoterpenic compounds are the most studied regarding hypotensive and anti-dyslipidemic/antidiabetic properties, whereas phenylpropanoids are very effective at avoiding platelet aggregation. Despite the number of studies performed, clinical trials are sparse and several aspects related to essential oil’s features, namely volatility and chemical variability, need to be considered in order to guarantee their efficacy in a clinical setting.

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Tomczyk, Michał, Olcay Ceylan, Marcello Locatelli, Angela Tartaglia, Vincenzo Ferrone y Cengiz Sarikurkcu. "Ziziphora taurica subsp. taurica: Analytical Characterization and Biological Activities". Biomolecules 9, n.º 8 (14 de agosto de 2019): 367. http://dx.doi.org/10.3390/biom9080367.

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The Lamiaceae family comprises many flowering plants classified into about 236 genera. The genus Ziziphora is one of the well-known genera of this family and its species are important in different fields of pharmaceutical, chemical, traditional, and folk medicines. The phytochemicals present in Ziziphora include monoterpenic essential oils, triterpenes, and phenolic substances. The aim of this paper was to study the phytochemical profile of Ziziphora taurica subsp. taurica and compare and evaluate the biological activities of its ethyl acetate (ZTT-EtOAc), methanolic (ZTT-MeOH), and aqueous (ZTT-W) extracts based on their enzyme inhibition and antioxidant capacities. Determination of total phenolic (TPC) and total flavonoid (TFC) contents as well as biological activities were determined using spectrophotometric procedures. Subsequently, the individual phenolic compounds were detected by liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS). In total, twenty-two different phenolic compounds were identified, including apigenin, ferulic acid, and luteolin which were the most common. ZTT-MeOH extract showed the best antioxidant activity, whereas ZTT-EtOAc extract was the most effective against tyrosinase and α-amylase. Ziziphora taurica subsp. taurica represents a potential source of natural compounds with positive effects on human health.

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García-Moruno, Emilia, Monica Ribaldone, Rocco Di Stefano, Lorenza Conterno y Annibale Gandini. "Study of five strains of Saccharomyces cerevisiae with regard to their metabolism towards geraniol". OENO One 36, n.º 4 (31 de diciembre de 2002): 221. http://dx.doi.org/10.20870/oeno-one.2002.36.4.963.

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Geraniol is the main monoterpenic alcohol of some red grapes occurring both in the free form (aromatic) and in the glycosilated (neutral) form. Free geraniol is transformed into other terpenic compounds (linalool and α-terpineol) through acid hydrolysis. During fermentation, yeasts also change must free geraniol into citronellol. The final aroma of wines is mainly due to both the unchanged geraniol and the formed citronellol, thus the key role played by yeasts in the vinification of those aromatic wines is proved. In the present work the metabolism towards geraniol of 5 different strains of S. cerevisiae were studied. The laboratory tests were carried out using a must from neutral grapes as the fermentation medium. Two different amounts of geraniol were added to the medium to evaluate the influence, if any, of the initial concentration of monoterpenic alcohol on the transformation rate of this compound. At different stages of fermentation geraniol and citronellol, as well as other terpenic compounds, were evaluated by means of GC on samples extracted by SPE on a C18 cartridge.The results proved that the yeast strain dramatically affects the amount of both geraniol and citronellol occurring in the medium at the end of fermentation. Therefore in the fermentation of aromatic musts in which geraniol is the main component, the choice of the yeast proves decisive for the quality of wines.The influence of tween 80, added to the medium as a source of oleic acid, on the biosynthesis of citronellol was evaluated as well. The results showed that tween 80 increases the production of citronellol, though no remarkable changes in the consumption of geraniol were observed. It can therefore be concluded that the production of citronellol by yeasts is a minor way of utilizing geraniol when no longer needed for the synthesis of cell fats.

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Wong, Yong Foo, Rachel N. West, Sung-Tong Chin y Philip J. Marriott. "Evaluation of fast enantioselective multidimensional gas chromatography methods for monoterpenic compounds: Authenticity control of Australian tea tree oil". Journal of Chromatography A 1406 (agosto de 2015): 307–15. http://dx.doi.org/10.1016/j.chroma.2015.06.036.

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Costa, Carina Pedrosa, Ana Rita Bezerra, Adelaide Almeida y Sílvia M. Rocha. "Candida Species (Volatile) Metabotyping through Advanced Comprehensive Two‐Dimensional Gas Chromatography". Microorganisms 8, n.º 12 (30 de noviembre de 2020): 1911. http://dx.doi.org/10.3390/microorganisms8121911.

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Microbial metabolomics is a challenge strategy that allows a comprehensive analysis of metabolites within a microorganism and may support a new approach in microbial research, including the microbial diagnosis. Thus, the aim of this research was to in-depth explore a metabolomics strategy based on the use of an advanced multidimensional gas chromatography for the comprehensive mapping of cellular metabolites of C. albicans and non-C. albicans (C. glabrata and C. tropicalis) and therefore contributing for the development of a comprehensive platform for fungal detection management and for species distinction in early growth times (6 h). The volatile fraction comprises 126 putatively identified metabolites distributed over several chemical families: acids, alcohols, aldehydes, hydrocarbons, esters, ketones, monoterpenic and sesquiterpenic compounds, norisoprenoids, phenols and sulphur compounds. These metabolites may be related with different metabolic pathways, such as amino acid metabolism and biosynthesis, fatty acids metabolism, aromatic compounds degradation, mono and sesquiterpenoid synthesis and carotenoid cleavage. These results represent an enlargement of ca. 70% of metabolites not previously reported for C. albicans, 91% for C. glabrata and 90% for C. tropicalis. This study represents the most detailed study about Candida species exometabolome, allowing a metabolomic signature of each species, which signifies an improvement towards the construction of a Candida metabolomics platform whose application in clinical diagnostics can be crucial to guide therapeutic interventions.

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Contreras-Puentes, Neyder, Manuel Salas-Moreno, Lina Mosquera-Chaverra, Leonomir Córdoba-Tovar y Antistio Alviz-Amador. "Volatile compounds from Phyla scaberrima (Juss. ex Pers.) Moldenke and Dysphania ambrosioides (L.) Mosyakin & Clemants as possible SARS-CoV-2 protease inhibitors: Identification and in-silico study". Journal of Pharmacy & Pharmacognosy Research 10, n.º 3 (1 de mayo de 2022): 469–85. http://dx.doi.org/10.56499/jppres21.1328_10.3.469.

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Context: COVID-19 is a pandemic that has affected the entire population, characterized by multisystemic involvement. With around 130 million cases of infection and more than 2.5 million deaths globally. However, the development of a low-efficacy treatment has led to the study of natural products as possible therapeutic alternatives against SARS-CoV-2. Aims: To identify volatile compounds present in two plants in the Colombian Pacific and carry out in-silico studies to search for promising inhibitory molecules against SARS-CoV-2 proteases. Methods: This research carried out the identification of metabolites of two plants identified in the Colombian Pacific, called P. scaberrima (Juss. ex Pers.) Moldenke y D. ambrosioides (L.) Mosyakin & Clemants. Ethanolic extracts were obtained by rotary-evaporation and determinated by GC-MS. Subsequently, in-silico studies were carried out by molecular docking against Mpro and PLpro using Autodock-vina 1.1. Also, a prediction of ADMET properties using SwissADME and GUSAR-Online server was performed. Results: Thus, 15 volatile compounds with similarities greater than 85% were identified from both extracts, mostly sesquiterpenic and monoterpenic compounds. The compounds that showed the highest affinity against Mpro were α-amorphene and phytol for PLpro. Likewise, these were contrasted with co-crystallized molecules such as boceprevir and VIR2-251 as control structures. Finally, the predictions of ADMET properties showed values consistent with the literature. Conclusions: Therefore, the follow-up of in-silico studies with these plants from Colombian pacific are considered as possible tools in the search for active molecules against proteases linked to virus.

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Kordali, Saban, Ahmet Cakir y Sunay Sutay. "Inhibitory Effects of Monoterpenes on Seed Germination and Seedling Growth". Zeitschrift für Naturforschung C 62, n.º 3-4 (1 de abril de 2007): 207–14. http://dx.doi.org/10.1515/znc-2007-3-409.

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Abstract Monoterpenes, the chemical constituents of essential oils found in plants, are known biologically active compounds. The present study was conducted to investigate the inhibitory effects of 30 monoterpenes including monoterpene hydrocarbons and oxygenated monoterpenes on seed germination and seedling growth of Amaranthus retroflexus, Chenopodium album and Rumex crispus under laboratory conditions. The monoterpenes were applied at contents of 10 and 20 μl for liquid compounds and 10 and 20 μg for solid compounds. The results show that most of the monoterpenes significantly inhibited seed germination and seedling growth of the tested plants. Oxygenated monoterpenes including β-citronellol, nerol and terpinen-4-ol completely inhibited seed germination and seedling growth of all tested plants. Their inhibitory effects were also stronger than that of the herbicide 2,4-D. In general, monoterpenes were less effective against seed germination and seedling growth of C. album as compared with R. crispus and A. retroflexus. Phytotoxic effects of monoterpene hydrocarbons were found to be lower than those of oxygenated monoterpenes. The alcohol derivatives of oxygenated monoterpenes were also found to be more phytotoxic as compared with their acetate derivatives. Based on the present results, it can be concluded that the oxygenated monoterpenes can be used as potential bio-herbicides.

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25

Haapanala, S., H. Hakola, H. Hellén, M. Vestenius, J. Levula y J. Rinne. "Is forest management a significant source of monoterpenes into the boreal atmosphere?" Biogeosciences Discussions 8, n.º 4 (10 de agosto de 2011): 8067–90. http://dx.doi.org/10.5194/bgd-8-8067-2011.

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Abstract. Volatile organic compounds (VOCs) including terpenoids are emitted into the atmosphere from various natural sources. Damaging the plant tissue is known to strongly increase their monoterpene release. We measured the terpenoid emissions caused by timber felling, i.e. those from stumps and logging residue. The emissions from stumps were studied using enclosures and those from the whole felling area using an ecosystem scale micrometeorological method, disjunct eddy accumulation (DEA). The compounds analyzed were isoprene, monoterpenes and sesquiterpenes. Strong emissions of monoterpenes were measured from both the stumps and from the whole felling area. The emission rate fell down rapidly within few months after the logging. In addition to fresh logging residue, the results suggest also other strong monoterpene sources to be present at the felling area. Those could include pre-existing litter, increased microbial activity and remaining undergrowth. To evaluate the possible importance of monoterpenes emitted from cut Scots pine forests in Finland annually, we conducted a rough upscaling. The resulting monoterpene release was about 15 kilotonnes per year which is more than 10 % of the monoterpene release from intact forests in Finland.

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26

Haapanala, S., H. Hakola, H. Hellén, M. Vestenius, J. Levula y J. Rinne. "Is forest management a significant source of monoterpenes into the boreal atmosphere?" Biogeosciences 9, n.º 4 (10 de abril de 2012): 1291–300. http://dx.doi.org/10.5194/bg-9-1291-2012.

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Abstract. Volatile organic compounds (VOCs) including terpenoids are emitted into the atmosphere from various natural sources. Damaging the plant tissue is known to strongly increase their monoterpene release. We measured the terpenoid emissions caused by timber felling, i.e. those from stumps and logging residue. The emissions from stumps were studied using enclosures and those from the whole felling area using an ecosystem-scale micrometeorological method, disjunct eddy accumulation (DEA). The compounds analyzed were isoprene, monoterpenes and sesquiterpenes. Strong emissions of monoterpenes were measured from both the stumps and from the whole felling area. The emission rate decreased rapidly within a few months after the logging. In addition to fresh logging residue, the results suggest also other strong monoterpene sources may be present in the felling area. These could include pre-existing litter, increased microbial activity and remaining undergrowth. In order to evaluate the possible importance of monoterpenes emitted annually from cut Scots pine forests in Finland, we conducted a rough upscaling calculation. The resulting monoterpene release was approximated to be on the order of 15 kilotonnes per year, which corresponds to about one tenth of the monoterpene release from intact forests in Finland.

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Eberhardt, Thomas L., Philip M. Sheridan y Jolie M. Mahfouz. "Monoterpene persistence in the sapwood and heartwood of longleaf pine stumps: assessment of differences in composition and stability under field conditions". Canadian Journal of Forest Research 39, n.º 7 (julio de 2009): 1357–65. http://dx.doi.org/10.1139/x09-063.

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Monoterpenes in exudates, phloem, and sapwood have received considerable attention relative to the active defenses of pine trees. However, little is known about the composition and function of the heartwood monoterpenes. To address this deficiency, monoterpene contents and relative compositions were determined for sapwood and heartwood samples from longleaf pine ( Pinus palustris Mill.) stumps monitored in the field for a 1 year period postharvest. Gas chromatography – mass spectrometry analysis of sapwood and heartwood sample extracts showed the total monoterpene contents for both declined at essentially the same rate. For sapwood, α-pinene continued to comprise about 75% of all compounds detected, while the proportion of β-pinene declined with time (15%–7%). For the heartwood, lower proportions of both α- and β-pinenes (64% and 10%, respectively) were offset by higher proportions of other monoterpenes (e.g., limonene, α-terpineol, borneol). The low proportion of β-pinene in very old turpentine and lightwood stump samples further suggested the lower stability of this particular monoterpene. While it has not been specifically demonstrated that the monoterpenes have an active role in the decay resistance of longleaf pine stump heartwood, these compounds do persist for a very long time and thus are available should they serve this function.

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Dragomanova, Stela, Velichka Andonova, Konstantin Volcho, Nariman Salakhutdinov, Reni Kalfin y Lyubka Tancheva. "Therapeutic Potential of Myrtenal and Its Derivatives—A Review". Life 13, n.º 10 (20 de octubre de 2023): 2086. http://dx.doi.org/10.3390/life13102086.

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The investigation of monoterpenes as natural products has gained significant attention in the search for new pharmacological agents due to their ability to exhibit a wide range in biological activities, including antifungal, antibacterial, antioxidant, anticancer, antispasmodic, hypotensive, and vasodilating properties. In vitro and in vivo studies reveal their antidepressant, anxiolytic, and memory-enhancing effects in experimental dementia and Parkinson’s disease. Chemical modification of natural substances by conjugation with various synthetic components is a modern method of obtaining new biologically active compounds. The discovery of new potential drugs among monoterpene derivatives is a progressive avenue within experimental pharmacology, offering a promising approach for the therapy of diverse pathological conditions. Biologically active substances such as monoterpenes, for example, borneol, camphor, geraniol, pinene, and thymol, are used to synthesize compounds with analgesic, anti-inflammatory, anticonvulsive, antidepressant, anti-Alzheimer’s, antiparkinsonian, antiviral and antibacterial (antituberculosis) properties. Myrtenal is a perspective monoterpenoid with therapeutic potential in various fields of medicine. Its chemical modifications often lead to new or more pronounced biological effects. As an example, the conjugation of myrtenal with the established pharmacophore adamantane enables the augmentation of several of its pivotal properties. Myrtenal–adamantane derivatives exhibited a variety of beneficial characteristics, such as antimicrobial, antifungal, antiviral, anticancer, anxiolytic, and neuroprotective properties, which are worth examining in more detail and at length.

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29

Schaefer, Peter R. y James W. Hanover. "Taxonomic Implications of Monoterpene Compounds of Blue and Engelmann Spruces". Forest Science 32, n.º 3 (1 de septiembre de 1986): 725–34. http://dx.doi.org/10.1093/forestscience/32.3.725.

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Abstract The monoterpenes of cortical oleoresin collected from mature blue and Engelmann spruce have significant diagnostic potential in taxonomic studies of these species, while seedling cortical monoterpenes appear to be less useful. Cortical monoterpene compounds were analyzed in 38 blue and 13 Engelmann spruce in the Scotch Creek drainage in southwestern Colorado, and in their 6-months-old progeny. The objective was to explore the utility of monoterpenes in studying natural hybridization between the two species. Twenty-two compounds were detected in the cortical oleoresin of mature trees, twelve of which were identified. Species differences were generally quantitative, with most statistically significant. Blue spruce oleoresin contained higher levels of tricyclene, alpha-pinene, camphene, and bornyl acetate, while Engelmann spruce oleoresin contained higher levels of beta-pinene, 3-carene, terpinolene, and several unknown compounds. Monoterpene content of seedlings differed appreciably from that of mature parents. The large increase in beta-pinene in Engelmann spruce seedlings was the most striking. A discriminant function analysis of mature tree data distinguished between blue and Engelmann spruce with no misclassifications. Forest Sci. 32:725-734.

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30

Magnard, Jean-Louis, Aymeric Roccia, Jean-Claude Caissard, Philippe Vergne, Pulu Sun, Romain Hecquet, Annick Dubois et al. "Biosynthesis of monoterpene scent compounds in roses". Science 349, n.º 6243 (2 de julio de 2015): 81–83. http://dx.doi.org/10.1126/science.aab0696.

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The scent of roses (Rosaxhybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribute to fragrance in roses. The RhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro and supports geraniol biosynthesis in planta.

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31

Malik, Tanzil Gaffar, Lokesh Kumar Sahu, Mansi Gupta, Bilal Ahmad Mir, Triratnesh Gajbhiye, Rashmi Dubey, Andrea Clavijo McCormick y Sudhir Kumar Pandey. "Environmental Factors Affecting Monoterpene Emissions from Terrestrial Vegetation". Plants 12, n.º 17 (31 de agosto de 2023): 3146. http://dx.doi.org/10.3390/plants12173146.

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Monoterpenes are volatile organic compounds that play important roles in atmospheric chemistry, plant physiology, communication, and defense. This review compiles the monoterpene emission flux data reported for different regions and plant species and highlights the role of abiotic environmental factors in controlling the emissions of biogenic monoterpenes and their emission fluxes for terrestrial plant species (including seasonal variations). Previous studies have demonstrated the role and importance of ambient air temperature and light in controlling monoterpene emissions, likely contributing to higher monoterpene emissions during the summer season in temperate regions. In addition to light and temperature dependence, other important environmental variables such as carbon dioxide (CO2), ozone (O3), soil moisture, and nutrient availability are also known to influence monoterpene emissions rates, but the information available is still limited. Throughout the paper, we identify knowledge gaps and provide recommendations for future studies.

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Valterová, Irena, Soňa Vašíčková, Miloš Buděšínský y Jan Vrkoč. "Constituents of frontal gland secretion of peruvian termites Nasutitermes ephratae". Collection of Czechoslovak Chemical Communications 51, n.º 12 (1986): 2884–95. http://dx.doi.org/10.1135/cccc19862884.

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The defense secretion of Nasutitermes ephratae soldiers was analyzed and its constituents were identified. The volatile fraction contains monoterpenic hydrocarbons α-pinene, camphene, sabinene, β-pinene, myrcene, 4-carene, 3-carene, α-terpinene, limonene, γ-terpinene, β-phellandrene, and terpinolene. From the non-volatile fraction four alcohols derived from trinervitane skeleton were isolated: 1(15),8(19)-trinervitadien-3α-ol (I), 1(15),8(19)-trinervitadien-2β,3α-diol (II) and its 2α,3α- (III) and 2α,3β- (IV) isomers. 3α-Hydroxy-1(15),8(19)-trinervitadien-2-one (V), which was also isolated, is probably an artefact formed during the work-up of the extract. The structure of 3β-hydroxy-1(15),8(19)-trinervitadien-2-one (VI) was determined on the basis of mass, IR and 1H NMR spectra, comparison with model compounds and analogy with the literature. The absolute configuration of the trinervitane skeleton was studied by CD spectra of tris(2,2,6,6-tetramethyl-3,5-heptanedionato)praseodymium complexes of the 2,3-diols II-IV and by the 1H NMR spectra of esters of the alcohol I with (R)- and (S)-α-methoxy-α-(trifluoromethyl)phenylacetic acid. The results obtained by both methods are identical and confirm the earlier suggested absolute configuration of the trinervitane skeleton.

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Meroni, Gabriele, Giulia Laterza, Alexios Tsikopoulos, Konstantinos Tsikopoulos, Sara Vitalini, Barbara Scaglia, Marcello Iriti, Luigi Bonizzi, Piera Anna Martino y Alessio Soggiu. "Antibacterial Potential of Essential Oils and Silver Nanoparticles against Multidrug-Resistant Staphylococcus pseudintermedius Isolates". Pathogens 13, n.º 2 (9 de febrero de 2024): 156. http://dx.doi.org/10.3390/pathogens13020156.

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Staphylococcus pseudintermedius is an emergent zoonotic agent associated with multidrug resistance (MDR). This work aimed to describe the antibacterial activity of four essential oils (EOs) and silver nanoparticles (AgNPs) against 15 S. pseudintermedius strains isolated from pyoderma. The four EOs, namely Rosmarinus officinalis (RO), Juniperus communis (GI), Citrus sinensis (AR), and Abies alba (AB), and AgNPs were used alone and in combination to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). All strains were MDR and methicillin-resistant. Among the antibiotic cohort, only rifampicin, doxycycline, and amikacin were effective. EOs’ chemical analysis revealed 124 compounds belonging to various chemical classes. Of them, 35 were found in AR, 75 in AB, 77 in GI, and 57 in RO. The monoterpenic fraction prevailed over the sesquiterpenic in all EOs. When EOs were tested alone, AB showed the lowest MIC followed by GI, AR, and RO (with values ranging from 1:128 to 1:2048). MBC increased in the following order: AB, AR, GI, and RO (with values ranging from 1:512 to 1:2048). MIC and MBC values for AgNPs were 10.74 mg/L ± 4.23 and 261.05 mg/L ± 172.74. In conclusion, EOs and AgNPs could limit the use of antibiotics or improve the efficacy of conventional therapies.

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Salakhutdinov, Nariman F., Konstantin P. Volcho y Olga I. Yarovaya. "Monoterpenes as a renewable source of biologically active compounds". Pure and Applied Chemistry 89, n.º 8 (26 de julio de 2017): 1105–17. http://dx.doi.org/10.1515/pac-2017-0109.

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AbstractMonoterpenes and their derivatives play an important role in the creation of new biologically active compounds including drugs. The review focuses on the data on various types of biological activity exhibited by monoterpenes and their derivatives, including analgesic, anti-inflammatory, anticonvulsant, antidepressant, anti-Alzheimer, anti-Parkinsonian, antiviral, and antibacterial (anti-tuberculosis) effects. Searching for novel potential drugs among monoterpene derivatives shows great promise for treating various pathologies. Special attention is paid to the effect of absolute configuration of monoterpenes and monoterpenoids on their activity.

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Dehsheikh, Anahita Boveiri, Mohammad Mahmoodi Sourestani, Paria Boveiri Dehsheikh, Javad Mottaghipisheh, Sara Vitalini y Marcello Iriti. "Monoterpenes: Essential Oil Components with Valuable Features". Mini-Reviews in Medicinal Chemistry 20, n.º 11 (17 de julio de 2020): 958–74. http://dx.doi.org/10.2174/1389557520666200122144703.

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Medicinal plants have a wide range of secondary metabolites including monoterpene. These volatile compounds are the main components of essential oils, belonging to the isoprenoid group and possessing valuable features for plants and humans. This review provides comprehensive information on chemical structures and classification of monoterpenes. It describes their biosynthesis pathways and introduces plant families and species rich in noteworthy monoterpenes. Bio-activities, pharmacological and pesticide effects as well as their mechanism of action are reported. Applications of these compounds in various industries are also included.

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Li, Haiyan, Manjula R. Canagaratna, Matthieu Riva, Pekka Rantala, Yanjun Zhang, Steven Thomas, Liine Heikkinen et al. "Atmospheric organic vapors in two European pine forests measured by a Vocus PTR-TOF: insights into monoterpene and sesquiterpene oxidation processes". Atmospheric Chemistry and Physics 21, n.º 5 (18 de marzo de 2021): 4123–47. http://dx.doi.org/10.5194/acp-21-4123-2021.

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Abstract. Atmospheric organic vapors play essential roles in the formation of secondary organic aerosol. Source identification of these vapors is thus fundamental to understanding their emission sources and chemical evolution in the atmosphere and their further impact on air quality and climate change. In this study, a Vocus proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF) was deployed in two forested environments, the Landes forest in southern France and the boreal forest in southern Finland, to measure atmospheric organic vapors, including both volatile organic compounds (VOCs) and their oxidation products. For the first time, we performed binned positive matrix factorization (binPMF) analysis on the complex mass spectra acquired with the Vocus PTR-TOF and identified various emission sources as well as oxidation processes in the atmosphere. Based on separate analysis of low- and high-mass ranges, 15 PMF factors in the Landes forest and nine PMF factors in the Finnish boreal forest were resolved, showing a high similarity between the two sites. Particularly, terpenes and various terpene reaction products were separated into individual PMF factors with varying oxidation degrees, such as lightly oxidized compounds from both monoterpene and sesquiterpene oxidation, monoterpene-derived organic nitrates, and monoterpene more oxidized compounds. Factors representing monoterpenes dominated the biogenic VOCs in both forests, with lower contributions from the isoprene factors and sesquiterpene factors. Factors of the lightly oxidized products, more oxidized products, and organic nitrates of monoterpenes/sesquiterpenes accounted for 8 %–12 % of the measured gas-phase organic vapors in the two forests. Based on the interpretation of the results relating to oxidation processes, further insights were gained regarding monoterpene and sesquiterpene reactions. For example, a strong relative humidity (RH) dependence was found for the behavior of sesquiterpene lightly oxidized compounds. High concentrations of these compounds only occur at high RH; yet similar behavior was not observed for monoterpene oxidation products.

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Schierer, Valentin, Cornelia Rieder-Gradinger y Erwin Rosenberg. "Method Comparison for the Identification and Characterization of Odorants from Scots Pine (Pinus sylvestris L.) and Oriented Strand Boards (OSB) Made Thereof by GC-MS and GC-FID/O Using Different Headspace Techniques". Chemosensors 11, n.º 10 (19 de octubre de 2023): 543. http://dx.doi.org/10.3390/chemosensors11100543.

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Volatile organic compounds (VOCs) from wood and wood composites are important contributors to odor profiles of indoor environments and can significantly influence human health and well-being. GC-MS/FID and gas chromatography (GC) with olfactometric detection (GC-O) are employed for the identification and characterization of odorants. Four different sample preparation methods are evaluated on wood strands and isocyanate adhesive–based oriented strand boards (OSBs) made from Pinus sylvestris L.: among these, dynamic headspace extraction thermal desorption ((dynamic) HS-TD), head space solid phase microextraction (HS-SPME), head space solid phase microextraction Arrow (HS-SPME Arrow), and liquid injection of a CH2Cl2 solvent extract. The olfactometric investigation revealed over 30 odor-active substances of cyclic and acyclic monoterpene, monoterpenoid ketone, monoterpenoid aldehyde, monoterpenoid alcohol, monoterpenoid ester, aliphatic aldehyde, alcohol, and acid and phenolic chemistry. Compared to liquid injection, (dynamic) HS-TD was found to result in a similar number of odorants (20 vs. 24), whereas HS SPME Arrow shows good performance with minimal instrumental effort, notably for monoterpene and aldehyde compounds. Native wood vs. OSB showed high concentrations of saturated and unsaturated aldehydes for the wood board sample. These findings demonstrate the capability of headspace methods for odorant detection and their suitability for standardization towards a database for wood and wood composites.

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Burčul, Franko, Ivica Blažević, Mila Radan y Olivera Politeo. "Terpenes, Phenylpropanoids, Sulfur and Other Essential Oil Constituents as Inhibitors of Cholinesterases". Current Medicinal Chemistry 27, n.º 26 (23 de julio de 2020): 4297–343. http://dx.doi.org/10.2174/0929867325666180330092607.

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: Essential oils constituents are a diverse family of low molecular weight organic compounds with comprehensive biological activity. According to their chemical structure, these active compounds can be divided into four major groups: terpenes, terpenoids, phenylpropenes, and "others". In addition, they may contain diverse functional groups according to which they can be classified as hydrocarbons (monoterpenes, sesquiterpenes, and aliphatic hydrocarbons); oxygenated compounds (monoterpene and sesquiterpene alcohols, aldehydes, ketones, esters, and other oxygenated compounds); and sulfur and/or nitrogen containing compounds (thioesters, sulfides, isothiocyanates, nitriles, and others). : Compounds that act as cholinesterase inhibitors still represent the only pharmacological treatment of Alzheimer´s disease. Numerous in vitro studies showed that some compounds, found in essential oils, have a promising cholinesterase inhibitory activity, such as α-pinene, δ-3-carene, 1,8-cineole, carvacrol, thymohydroquinone, α- and β-asarone, anethole, etc. : Essential oils constituents are a diverse family of low molecular weight organic compounds with comprehensive biological activity. According to their chemical structure, these active compounds can be divided into four major groups: terpenes, terpenoids, phenylpropenes, and "others". In addition, they may contain diverse functional groups according to which they can be classified as hydrocarbons (monoterpenes, sesquiterpenes, and aliphatic hydrocarbons); oxygenated compounds (monoterpene and sesquiterpene alcohols, aldehydes, ketones, esters, and other oxygenated compounds); and sulfur and/or nitrogen containing compounds (thioesters, sulfides, isothiocyanates, nitriles, and others).

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Li, De Wen, Yi Shi, Xing Yuan He y Yuan Gang Zu. "Effects of Elevated CO₂ and O₃ Concentrations on Isoprenoid Emissions from Pinus tabulaeformis". Applied Mechanics and Materials 522-524 (febrero de 2014): 264–71. http://dx.doi.org/10.4028/www.scientific.net/amm.522-524.264.

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Isoprene and monoterpenes have indirect effects on ozone concentration, methane lifetime and aerosol formation. At the same time, the atmospheric composition change (reflected in elevated CO2and O3concentrations) can affect the speciation of monoterpenes / isoprenoids and magnitude of isoprene and monoterpenes fluxes. Ambient concentrations of CO2and O3were 342 μmolmol-1and 40 nmolmol-1, respectively. The effects of elevated CO2(700 μmolmol-1) and O3(80 nmolmol-1) concentrations on isoprenoid emission rates and patterns fromPinustabulaeformiswere studied in open top chambers (OTCs). The released volatiles were quantified by thermal desorption and gas chromatography with flame ionization detector (GC-FID). The study showed that α-pinene was the main compound emitted from Ptabulaeformis, accounting for more 51.5 - 72.6% of the detected volatile compounds. The emissions of isoprene and monoterpenes were reduced in response to elevated CO2concentrations. Exposure to elevated O3for 3 years significantly promoted the isoprene and monoterpenes emissions (p<0.05). Compared with ambient, elevated O3concentration increased isoprene emission from Ptabulaeformisby about 270.5 ± 13.5%. The response of monoterpene emission to elevated O3may vary during the course of exposure to the pollutant. The patterns of monoterpene and isoprene emissions under combined elevated CO2and O3concentrations were similar to those under elevated CO2concentration alone.

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Lanaridis, Panos, Marie-Jeanne Salaha, Irini Tzourou, Epaminondas Tsoutsouras y S. Karagiannis. "Volatile compounds in grapes and wines from two Muscat varieties cultivated in Greek islands". OENO One 36, n.º 1 (31 de marzo de 2002): 39. http://dx.doi.org/10.20870/oeno-one.2002.36.1.981.

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The concentrations of free and glycosidically linked monoterpenes and volatile alcohols in grapes and wines from the cultivars Muscat lefko and Muscat of Alexandria, cultivated in the islands of Samos and Lemnos respectively, were determined. The relationship between free and linked monoterpenes in grapes and wines as well as the relationship between grapes and wines in their monoterpene content was investigated, showing some differences between the two cultivars and the different vineyards. It is also demonstrated that skin-contact for 8h at a temperature up to 15 °C, resulted in marked increases in the concentrations of free and linked monoterpenes in wines from both Muscat cultivars.

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Kutchin, Alexander V., Svetlana A. Rubtsova, Olga M. Lezina, Denis V. Sudarikov, Larisa L. Frolova, Irina V. Loginova, Alexey V. Popov y Olga N. Grebyonkina. "Studies on oxidative transformations of thiols, sulfides and alcohols in the presence of chlorine dioxide". Pure and Applied Chemistry 89, n.º 10 (26 de septiembre de 2017): 1379–401. http://dx.doi.org/10.1515/pac-2016-1209.

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AbstractOur recent studies on the chemical reactivity of chlorine dioxide in the reactions with sulfur and oxygen containing compounds are reviewed. A special attention is given to chlorine dioxide interaction with alkyl, aryl, heteroaryl, monoterpenyl thiols, sulfides and disulfides. The data on the oxidation of monoterpene alcohols and phenols are also presented. The directions of reactions depending on the structure of the compounds were identified.

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Soares-Castro, Pedro, Filipa Soares y Pedro M. Santos. "Current Advances in the Bacterial Toolbox for the Biotechnological Production of Monoterpene-Based Aroma Compounds". Molecules 26, n.º 1 (28 de diciembre de 2020): 91. http://dx.doi.org/10.3390/molecules26010091.

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Monoterpenes are plant secondary metabolites, widely used in industrial processes as precursors of important aroma compounds, such as vanillin and (−)-menthol. However, the physicochemical properties of monoterpenes make difficult their conventional conversion into value-added aromas. Biocatalysis, either by using whole cells or enzymes, may overcome such drawbacks in terms of purity of the final product, ecological and economic constraints of the current catalysis processes or extraction from plant material. In particular, the ability of oxidative enzymes (e.g., oxygenases) to modify the monoterpene backbone, with high regio- and stereo-selectivity, is attractive for the production of “natural” aromas for the flavor and fragrances industries. We review the research efforts carried out in the molecular analysis of bacterial monoterpene catabolic pathways and biochemical characterization of the respective key oxidative enzymes, with particular focus on the most relevant precursors, β-pinene, limonene and β-myrcene. The presented overview of the current state of art demonstrates that the specialized enzymatic repertoires of monoterpene-catabolizing bacteria are expanding the toolbox towards the tailored and sustainable biotechnological production of values-added aroma compounds (e.g., isonovalal, α-terpineol, and carvone isomers) whose implementation must be supported by the current advances in systems biology and metabolic engineering approaches.

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Li, Chunhong, Sreelatha Sarangapani, Qian Wang, Kumar Nadimuthu y Rajani Sarojam. "Metabolic Engineering of the Native Monoterpene Pathway in Spearmint for Production of Heterologous Monoterpenes Reveals Complex Metabolism and Pathway Interactions". International Journal of Molecular Sciences 21, n.º 17 (26 de agosto de 2020): 6164. http://dx.doi.org/10.3390/ijms21176164.

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Spearmint produces and stores large amounts of monoterpenes, mainly limonene and carvone, in glandular trichomes and is the major natural source of these compounds. Towards producing heterologous monoterpenes in spearmint, we first reduced the flux into the native limonene pathway by knocking down the expression of limonene synthase (MsLS) by RNAi method. The MsLS RNAi lines exhibited a huge reduction in the synthesis of limonene and carvone. Detailed GC-MS and LC-MS analysis revealed that MsLS RNAi plants also showed an increase in sesquiterpene, phytosterols, fatty acids, flavonoids, and phenolic metabolites, suggesting an interaction between the MEP, MVA shikimate and fatty acid pathways in spearmint. Three different heterologous monoterpene synthases namely, linalool synthase and myrcene synthase from Picea abies and geraniol synthase from Cananga odorata were cloned and introduced independently into the MsLS RNAi mutant background. The expression of these heterologous terpene synthases resulted mainly in production of monoterpene derivatives. Of all the introduced monoterpenes geraniol showed the maximum number of derivatives. Our results provide new insights into MEP pathway interactions and regulation and reveals the existence of mechanisms for complex metabolism of monoterpenes in spearmint.

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Sudarikov, Denis V., Liliya E. Nikitina, Patrick Rollin, Evgeniy S. Izmest’ev y Svetlana A. Rubtsova. "Monoterpene Thiols: Synthesis and Modifications for Obtaining Biologically Active Substances". International Journal of Molecular Sciences 24, n.º 21 (1 de noviembre de 2023): 15884. http://dx.doi.org/10.3390/ijms242115884.

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Monoterpene thiols are one of the classes of natural flavors that impart the smell of citrus fruits, grape must and wine, black currants, and guava and are used as flavoring agents in the food and perfume industries. Synthetic monoterpene thiols have found an application in asymmetric synthesis as chiral auxiliaries, derivatizing agents, and ligands for metal complex catalysis and organocatalysts. Since monoterpenes and monoterpenoids are a renewable source, there are emerging trends to use monoterpene thiols as monomers for producing new types of green polymers. Monoterpene thioderivatives are also known to possess antioxidant, anticoagulant, antifungal, and antibacterial activity. The current review covers methods for the synthesis of acyclic, mono-, and bicyclic monoterpene thiols, as well as some investigations related to their usage for the preparation of the compounds with antimicrobial properties.

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Smolander, S., Q. He, D. Mogensen, L. Zhou, J. Bäck, T. Ruuskanen, S. Noe et al. "Comparing three vegetation monoterpene emission models to measured gas concentrations with a model of meteorology, air chemistry and chemical transport". Biogeosciences Discussions 10, n.º 11 (28 de noviembre de 2013): 18563–611. http://dx.doi.org/10.5194/bgd-10-18563-2013.

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Abstract. Biogenic volatile organic compounds (BVOCs) are essential in atmospheric chemistry because of their chemical reactions that produce and destroy tropospheric ozone, their effects on aerosol formation and growth, and their potential influence on global warming. As one of the important BVOC groups, monoterpenes have been a focus of scientific attention in atmospheric research. Detailed regional measurements and model estimates are needed to study emission potential and the monoterpene budget on a global scale. Since the use of empirical measurements for upscaling is limited by many physical and biological factors such as genetic variation, temperature and light, water availability, seasonal changes, and environmental stresses, comprehensive inventories over larger areas are difficult to obtain. We applied the boundary layer-chemistry-transport model SOSA to investigate Scots pine (Pinus sylvestris) monoterpene emissions in a boreal coniferous forest at the SMEAR II site, Southern Finland. SOSA was applied to simulate monoterpene emissions with three different emission modules: the semi-empirical G95, MEGAN 2.04 with improved descriptions of temperature and light responses and including also carbonyl emissions, and a process-based model SIM-BIM. For the first time, the emission models included seasonal and diurnal variations in both quantity and chemical species of emitted monoterpenes, based on parameterizations obtained from field measurements. Results indicate that modelling and observations agreed reasonably well, and that the model can be used for investigating regional air chemistry questions related to monoterpenes. The predominant modelled monoterpene concentrations, α-pinene and Δ3-carene, are consistent with observations.

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46

Dindorf, T., U. Kuhn, L. Ganzeveld, G. Schebeske, P. Ciccioli, C. Holzke, R. Köble, G. Seufert y J. Kesselmeier. "Emission of monoterpenes from European beech (Fagus sylvatica L.) as a function of light and temperature". Biogeosciences Discussions 2, n.º 1 (27 de enero de 2005): 137–82. http://dx.doi.org/10.5194/bgd-2-137-2005.

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Abstract. Using a dynamic branch enclosure technique European beech (Fagus sylvatica L.) was characterised as a strong emitter of monoterpenes, with sabinene being the predominant compound released. Since monoterpene emission was demonstrated to be a function of light and temperature, application of light and temperature dependent algorithms resulted in reasonable agreement with the measured data. Furthermore, during high temperature periods the depression of net CO2 exchange during midday (midday depression) was accompanied by a depression of monoterpene emission on one occasion. The species dependent standard emission factor and the light and temperature regulated release of monoterpenes is of crucial importance for European VOC emissions. All measurements were performed within the framework of the ECHO project (Emission and CHemical transformation of biogenic volatile Organic compounds) during two intensive field campaigns in the summers of 2002 and 2003.

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47

Pecarski, Danijela, Zorica Knezevic-Jugovic, Suzana Dimitrijevic-Brankovic, Katarina Mihajilovski y Slobodan Jankovic. "Comparative analysis of the chemical composition and antimicrobal activities of some of Lamiaceae family species and Eucaliptus (Eucaliptus globules M)". Acta Periodica Technologica, n.º 45 (2014): 201–13. http://dx.doi.org/10.2298/apt1445201p.

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The aim of this study was to evaluate and compare the antimicrobial activity of four essential oils that belong to Lamiaceae family (sage, oregano, thyme) and eucalyptus oil. Gas chromatography coupled with mass spectrometry (GC-MS) revealed that the highest percent of essential oils 98.93% include three classes of compounds - monoterpene hydrocarbons, aromatic hydrocarbons and oxidized monoterpenes. The main components are oxidized monoterpenes: carvacrol (59.03%); thymol (36.12%), eucalyptol (20.66%), hydrocarbon monoterpenes: limonene (30.96%) and ?-pinene (12.21%) and aromatic monoterpene, p-cymene (22.25%) All essential oils showed great potential of antimicrobial activity against several bacteria and yeast C. albicans, using the agar diffusion method with wells. Minimum inhibitory concentration (MIC) for the essential oils has been determined by the broth dilution method and valued in the range from 1 to 5 ?L/m, depending on the essential oil and bacteria tested, and up to 100 ?L/ml for C. albicans. The essential oils of Lamiaceae family exhibited a strong antibacterial activity for tested microorganisms, while the essential oils of thyme were especially recognized.

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Zorić, Martina, Saša Kostić, Marko Kebert, Nebojša Kladar, Biljana Božin y Saša Orlović. "Volatile organic compounds of Tilia cordata Mill. from Serbia, in terms of ecosystem services". Topola, n.º 206 (2020): 21–28. http://dx.doi.org/10.5937/topola2006021z.

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It is considered that different plant organic compounds, known as phytoncides are creditable for positive effects of Forest therapy on human health. Ongoing pandemic has also put these compounds in research focus considering potential use for novel corona virus treatment. This research was conducted in order to examine the potential of Tilia cordata Mill. considering volatile organic compounds (VOCs) content for the use in Forest therapy. In order to determine qualitative and quantitative content of phytoncides, as well the variability among genotypes growing in the same environmental conditions, leaf samples from genotypes of T. cordata were collected from the Fruška gora (Serbia) during 2019. VOCs determined in fresh herbal material were analyzed by HeadspaceGC/MS and VOCs determined in essential oil were obtained by GC/MS. The results showed the presence of 17 different phytoncides (monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, aliphatic compounds and diterpenes) in all tested genotypes. According to the mean values of the obtained results, the most abundant classes of phytoncides among the examined genotypes were monoterpene hydrocarbons (87.05), followed by aliphatic compounds (36.59) and oxygenated sesquiterpenes (34.60). The highest coefficient of variation (CV) among phytoncide content in tested T. cordata genotypes has been observed within oxygenated monoterpenes (43.12%), sesquiterpene hydrocarbons (28.18%), and diterpenes (27.04%). Some individual monoterpene hydrocarbons, such as o-cymene (19.92%) and a-pinene (17.40%) had the highest CV in terms of its presence in analyzed genotypes. In addition, the principal component analysis (PCA) showed more notable clustering within the VOCs determined in essential oil in comparison to VOCs determined in fresh herbal material. Considering the phytoncide content detected in T. cordata leaves, this species has high potential for the use in human health improvement within Forest therapy.

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Song, Mei, Claudio Fuentes y Elizabeth Tomasino. "Chemo-diversity of chiral monoterpenes in different styles of Riesling wine from different regions". OENO One 56, n.º 3 (22 de julio de 2022): 155–65. http://dx.doi.org/10.20870/oeno-one.2022.56.3.4834.

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Monoterpenes are important characteristic compounds for aromatic white wines, including Riesling, but their enantiomer composition has been little explored in wine. Enantiomers can differ depending on region and style, as they are sensitive to environmental factors, and thus could be used for wine authentication. Thirteen monoterpene isomers were quantified by HS-SPME-MDGC-MS in fifty-four commercial Riesling wines from three wine styles (dry, medium dry and medium sweet) and four well-established wine-growing regions in Germany, France (Alsace) and the USA (New York and Oregon). Significant differences were found for nine out of the 13 enantiomers among different regions and eight enantiomers among styles. X-Y scatterplots of enantiomer pair concentrations, with excellent fitted lines, implies low variation of enantiomeric ratios from each region. The study suggests that wines from different regions and styles were differentiated by chiral monoterpene profiles. Chiral monoterpene analyses could provide supporting information in Riesling wine authentication by offering an objective measure of flavour quality, as these compounds are key compounds for Riesling aroma and flavor.

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50

Leufvén, A. y G. Birgersson. "Quantitative variation of different monoterpenes around galleries of Ips typographus (Colleoptera: Scolytidae) attacking Norway spruce". Canadian Journal of Botany 65, n.º 5 (1 de mayo de 1987): 1038–44. http://dx.doi.org/10.1139/b87-144.

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Oxygenated and hydrocarbon monoterpenes present in gallery walls in the phloem at different phases of an attack by Ips typographus and associated microorganisms on Norway spruce trees were quantified. The concentration of monoterpene hydrocarbons rose rapidly at the onset of beetle attack and reached a maximum in the phloem surrounding nuptial chambers that were recently prepared by males. Thereafter, amounts decreased rapidly and then increased again in late attack phases. During the attack, the variation in the amounts of monoterpene hydrocarbons in the gallery walls was partly reflected by some oxygenated monoterpenes, such as myrtenol, present in the same tissue. Borneol, verbenone, terpinene-4-ol, and α-terpineol were present in low quantities in the early phases of attack, but large amounts of these compounds were found in gallery walls during later phases. The bark beetle semiochemicals, cis- and trans-verbenol, had their concentration maxima in gallery walls of finished nuptial chambers. Results of the present study suggest that some bark beetle semiochemicals are produced extraneously to the beetle by microorganisms such as yeasts. A simple model for the production of oxygenated monoterpenes in early and late Ips typographus attack phases is presented.

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