Literatura académica sobre el tema "Monoterpenic compounds"
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Artículos de revistas sobre el tema "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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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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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.
Tesis sobre el tema "Monoterpenic compounds"
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Paulino, Bruno Nicolau 1989. "Otimização de processos biotecnológicos para a produção de compostos de aroma a partir de substratos monoterpênicos = Optimization of biotechnological processes for the production of aroma compounds from monoterpenic substrates". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254209.
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Orientador: Gláucia Maria PastoreDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A crescente demanda por processos que tenham impacto ambiental reduzido, rendimentos consideráveis e ainda custos minimizados recorrem à biotecnologia como uma ciência que pode tornar essa necessidade uma realidade. Processos biotecnológicos para a produção de compostos de interesse industrial como biocorantes, açúcares funcionais, biosurfactantes e biodiesel são uma tendência no meio científico e ganham destaque pela inovação, resultados e aplicações obtidos. O apelo comercial dos produtos biotecnológicos é outro fator que influencia as pesquisas haja vista que esses produtos são considerados naturais e tem-se comprovado que muitos deles apresentam atividades biológicas relevantes. O aroma é um importante atributo dos alimentos e pode ser produzido via biotecnológica a partir de substratos de baixo custo. A utilização de resíduos agro-industriais com alto teor nesses substratos, como por exemplo, resíduos ricos em monoterpenos são de grande interesse na biotecnologia de produção de aromas. Além disso, a utilização de micro-organismos isolados de diferentes fontes como biocatalisadores na produção desses compostos é outra perspectiva, muito explorada e ainda desafiadora. A biotransformação de monoterpenos para a produção de compostos de aroma é vantajosa quando comparada com a síntese química clássica. Contudo, alguns problemas ainda devem ser minimizados, como sensibilidade dos biocatalisadores à toxicidade dos substratos ou condições operacionais e baixos rendimentos. Assim, a seleção de novos biocatalisadores, como micro-organismos endofíticos, o uso de ferramentas de engenharia genética e a utilização de métodos estatísticos de otimização de processos são promissores e caracterizam-se como a nova vertente na área de bioaromas, contornando as desvantagens até então limitantes dos processos de biotransformação. Eles permitem em alguns casos, o aumento de escala e dessa forma a real aplicação da bioconversão microbiana na indústria. Assim, trabalhos que visem selecionar novos biocatalisadores é ainda uma necessidade e quando aliados a otimização de processos podem fornecer caminhos para que os rendimentos da bioconversão de monoterpenos sejam aumentados. Nesse contexto, o presente trabalho visou selecionar micro-organismos com potencial para a bioconversão de monoterpenos de baixo custo e presentes em grandes quantidades em resíduos agro-industriais, como 'alfa'-pineno e R-(+)-limoneno, para a produção de compostos de aroma valorizados comercialmente, S-(-)-verbenona e 'alfa'-terpineol. O capítulo 1 traz uma revisão sobre os compostos monoterpênicos, abordando suas características químico-estruturais, biossíntese e recentes aplicações terapêuticas, além do seu uso como substratos na biotecnologia de produção de compostos de aroma. O capítulo 2 é dividido em duas partes: a parte I mostra os resultados de um screening realizado com 81 linhagens de fungos isolados de diferentes fontes, entre eles, fungos endofíticos, utilizados no estudo do potencial de biotransformação de R-(+)-limoneno e 'alfa'-pineno. A parte II descreve a otimização do processo de produção de S-(-)-verbenona biotecnológica a partir de ?-pineno por uma linhagem de fungo endofítico, ainda não identificado, isolado da romã (Punica granatum). O uso de um Delineamento Composto Central Rotacional (DCCR) de 4 variáveis proporcionou o estabelecimento de condições mais favoráveis ao processo, elevando a concentração de verbenona que era de 66 mg.L-1 para aproximadamente 108 mg.L-1 em um dos ensaios do DCCR e em torno de 98 mg.L-1 no ensaio de validação. O capítulo 3 aborda a otimização do processo biotecnológico de produção de ?-terpineol a partir de R-(+)-limoneno pela linhagem Bacillus tequilensis isolada de resíduos de processamento de frutas cítricas. Após a otimização e validação do processo nas condições consideradas ótimas através da análise de superfícies de resposta, a concentração de ?-terpineol passou de 25 mg.L-1 para 85 mg.L-1. Portanto, os resultados obtidos no trabalho mostraram um ganho de rendimento nos processos de bioconversão de substratos monoterpênicos e que a otimização de processos é uma importante ferramenta para a melhoria das condições experimentais possibilitando trabalhos futuros que envolvam aumento de escala
Abstract: The growing demand for processes that reduce environmental impacts, have high yields and costs minimized uses biotechnology as a science that can make this need into a reality. Biotechnological processes for the production of industrial interesting compounds, such as biocolorant, functional sugars, biosurfactants and biodiesel, are a trend in the scientific field and are highlighted by innovation, application and results obtained. The commercial appeal of biotechnological products is another factor that stimulates researches since these products are considered natural and has been proven that many of them presents significant biological activities. The flavor is an important attribute of food and can be produced through biotechnological processes from low-cost-substrates. The use of agro-industrial wastes with high content of these substrates, such as residues rich in monoterpenes, is of great interest in biotechnology. Furthermore, the use of micro-organisms isolated from several sources as biocatalysts in the production of flavor compounds is another well-explored and challenging perspective. The biotransformation of terpenes for aroma compounds production is advantageous when compared with chemical synthesis. However, there are still some problems that must be minimized like biocatalysts sensitivity, toxicity of substrates and low yields. Thus, the selection of new biocatalysts, such as endophytic micro-organisms, use of genetic engineering and statistical methods for optimization of processes are promising and characterize a new perspective in bioaromas field. Thereby, works that search for new biocatalysts are necessary and associated with optimization processes can improve the monoterpenes bioconvertion. In this context, the objective of this work was the screening and selection of micro-organisms that are able to realize the biotransformation of low cost monoterpenes, 'alfa'-pinene and limonene, into high-value aroma compounds, such as verbenone and 'alfa-terpineol. The chapter 1 presents a current review on monoterpenes, showing their chemical characteristics, biosynthesis and recent therapeutic applications, besides their potential use as substrates for bioflavor production. The chapter 2 is divides in two parts: the first one shows the results of the screening of 81 strains of fungi isolated from several sources, including endophytic strains, for biotransformation of limonene and ?-pinene. The second part describes the optimization process for biotechnological verbenone production from "alfa'-pinene by a non-indentified fungal strain, isolated from pomegranate (Punica granatum). The use of a central composite rotatable design (CCRD) of 4 variables provided the optimal conditions for this process, increasing the verbenone concentration from 66 mg.L-1 to 108 mg.L-1 in one of the CCRD assays and 98 mg.L-1 after validation. The chapter 3 also shows an optimization study, in this case using limonene as substrate and the product obtained was ?-terpineol. The biocatalyst used was a bacterial strain, identified as Bacillus tequilensis, isolated from citrus fruit processing waste. After the optimization and validation in the best conditions obtained through the surface response analysis, the concentration of ?-terpineol reached was 85 mg.L-1. Therefore, the results obtained in this work show an improve of the yields in the biotransformation of both monoterpenic substrates and that optimization of processes is an important tool for the progress of future works involving scale-up studies
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos
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Molina, Gustavo 1983. "Biotechnological production of aroma compounds by the biotransformation of terpenes = Produção biotecnológica de compostos de aroma por biotransformação de terpenos". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254207.
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Orientador: Gláucia Maria PastoreTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho de doutorado teve como principal objetivo estudar a produção biotecnológica de compostos de aroma a partir da biotransformação de terpenos, analisando potenciais biocatalisadores, processos bioquímicos diferenciados e a otimização das condições de processo envolvidas na produção destes aromas naturais para possíveis aplicações industriais. Inicialmente, o trabalho prático foi direcionado para uma série de estudos com o fungo Fusarium oxysporum 152B, visando complementar os recentes avanços alcançados pelo grupo de pesquisa na caracterização e otimização da bioconversão de R-(+)-limoneno em ?-terpineol. Desta forma, os resultados foram promissores, demonstrando o grande potencial e versatilidade deste fungo para a área, sendo que este biocatalisador foi capaz de produzir diferentes metabólitos a partir dos substratos S-(?)-limoneno, ?-pineno, ?-terpineno e linalol. Na sequência, o trabalho visou avaliar a bioconversão de S-(?)-limoneno para limoneno-1,2-diol em maiores detalhes. A produção de limoneno-1,2-diol, em condições não otimizadas, chegou a 1,2 g.L-1, sendo que foi detectada a continuação desta via metabólica quando este produto foi posteriormente metabolizado a 1-hidroxi-2- oxolimoneno, sugerindo que o fungo Fusarium oxysporum 152B possui uma via de degradação de limoneno recentemente descoberta. O trabalho prático visou também a otimização da produção de limoneno-1,2-diol por meio de uma estratégia sequencial de experimentos. Com base nas análises estatísticas, a produção deste composto a partir da bioconversão de S-(?)-limoneno pelo fungo Fusarium oxysporum 152B chegou a 3,7 g.L-1, utilizando pH 6,5, 5 g.L-1 de substrato, a 28 oC e 250 rpm de agitação. Além disso, esta foi a primeira descrição da utilização do resíduo agroindustrial conhecido como manipueira, originada ao longo do processamento da mandioca, para a produção de biomassa deste fungo, bem como uma das maiores concentrações de limoneno-1,2-diol reportadas na literatura específica. Além disso, o trabalho conduzido visou realizar uma série de comparações práticas entre a biotransformação de R-(+)-limoneno a ?-terpineol e a bioconversão de S-(?)-limoneno a limoneno-1,2-diol, pela mesma linhagem. Adicionalmente, este foi o primeiro trabalho que analisou as diferenças ultraestruturais causadas no biocatalisador ao longo do processo de bioconversão destes substratos, por meio de microscopia eletrônica de varredura e transmissão. Finalmente, foi estudada a otimização da produção de ?-terpineol, a partir da biotransformação de limoneno, utilizando o biocatalisador reconhecido como Sphingobium sp. Após o trabalho prático e análise estatística dos dados, observou-se que as melhores condições para desenvolvimento deste processo foram pH 7,0, concentração de limoneno de 350 g.L-1, agitação de 200 rpm e 28 oC. Nestas condições, a produção deste álcool monoterpênico chegou a 500 g.L-1, que pode ser considerada como a maior concentração de ?-terpineol já relatada na bibliografia de processos biotecnológicos.
Abstract: This work aimed to study the biotechnological production of aroma compounds from the biotransformation of terpenes, analyzing potential biocatalysts, biochemical processes and optimization of process conditions involved in the production of natural flavors for industrial applications. Initially, the practical work was directed to a series of studies with the fungal strain Fusarium oxysporum 152B, aiming to enhance the knowledge obtained in recent advances achieved by our research group in the characterization and optimization of the biotransformation of R-(+)-limonene into ?-terpineol. Thus, the results were promising, showing the great potential and versatility of this fungus to the specific area, and this biocatalyst was able to produce new metabolites from substrates S-(?)-limonene, ?-pinene, ?-terpinene and linalool. In the sequence, this study aimed at assessing the bioconversion of S-(?)-limonene into limonene-1,2-diol in greater detail. Thus, chapters 3, 4 and 5 were designed to a better characterization of this pathway. The production of this compound under non-optimized conditions, reached 1.2 gL-1, and the continuation of this pathway has been detected when this product was subsequently metabolized to 1-hydroxy-2-oxolimonene, suggesting that the fungus Fusarium oxysporum 152B might have a limonene degradation pathway only recently discovered. The practical work also conducted an extensive optimization of the production of limonene-1,2-diol by means of a sequential strategy. Based on statistical analyzes, the production of this compound from the bioconversion of S-(?)-limonene by the fungus Fusarium oxysporum 152B reached 3.7 gL-1, using pH 6.5, 5 gL-1 of substrate at 28 ° C and 250 rpm agitation. Moreover, this is the first description of the use of agroindustrial residue known as cassava wastewater, for the production of this fungal biomass, as well as one of the highest concentration of biotechnological limonene-1,2-diol reported in the specific literature. In addition, the research conducted aimed to perform a series of comparisons between practical conditions involved in the biotransformation of R-(+)-limonene into ?-terpineol, and the bioconversion of S-(?)-limonene into limonene-1,2-diol, for the same strain. Additionally, this is the first study that reported the ultrastructural differences along the bioconversion process of these substrates by means of scanning and transmission electron microscopy. Finally, this work evaluated the optimization of the production of ?-terpineol from the biotransformation of limonene using the biocatalyst recognized as Sphingobium sp. After the practical work and statistical analysis, it was observed that the best conditions for developing this process were pH 7.0, concentration of limonene 350 g L-1, agitation at 200 rpm and 28 oC. Accordingly, the production of the monoterpe alcohol reached 500 g.L-1, which can be considered as the highest concentration of ?-terpineol already reported in the literature for biotechnological processes.
Doutorado
Ciência de Alimentos
Doutor em Ciência de Alimentos
3
Kahnt, Ariane. "Semivolatile compounds from atmospheric monoterpene oxidation". Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-93492.
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This PhD thesis aims to improve the knowledge on the processes and chemical species in the gas- and particle-phases that are involved in the production of secondary organic aerosol (SOA) from monoterpene oxidation in the atmosphere.
A denuder/filter technique that enabled the simultaneous sampling of gaseous and particulate compounds was applied in the present study. The sampling technique was comprehensively characterised and optimised using twelve atmospherically relevant carbonyl compounds. The present study improved the denuder coating procedure and the sampling performance. An additional coating with the derivatisation reagent, 2,4‑dinitrophenylhydrazine (DNPH), reduced the break-through potential (e.g., from 98% to 0.9% for methyl vinyl ketone) and the fraction of carbonyl compounds on the filter material (e.g., from 8.7% to 0% for acetone).
Calibration experiments against an aerosol chamber were performed to reduce the relative standard deviation (RSD) of the calibration points in the denuder measurements. The RSDs were reduced by half for acetone, acetaldehyde, methyl vinyl ketone, glyoxal, benzaldehyde and campholenic aldehyde using a XAD‑4/DNPH denuder, and the quantification error was also reduced.
This sampling technique was then applied to a series of α- and β-pinene ozonolysis experiments. The present study examined the influence of an OH radical scavenger (CO), and hence the HO2/RO2 ratio, on the SOA formation, product distribution and partitioning behaviour of selected oxidation products in conjunction with different seed particle acidities.
It was shown that SOA yields increased by about 8% in α-pinene ozonolysis when CO and acidic seed particles co-existed, whereas only a marginal difference was observed (increase of 2%) for β-pinene compared to neutral seed particles.
From the denuder/filter sample analysis, it was possible to tentatively identify a new compound from the α-pinene ozonolysis, i.e., terpenylic aldehyde. Gas- and particle-phase yields were estimated for the first time for this compound (i.e., 1% and 0.4%, respectively). The atmospheric relevance of terpenylic aldehyde was demonstrated based on ambient filter measurements and a possible formation pathway was suggested.
Furthermore, the present study provided an additional explanation for enhanced SOA formation when acidic seed particles are used in monoterpene ozonolysis. It was demonstrated that the isomerisation of monoterpene oxides on acidic seed particles leads to the formation of highly reactive SOA precursors, whose subsequent reaction with ozone contributes significantly to SOA formation.
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Pimentel, Mariana Recco 1984. "Produção de compostos de aroma a partir da biotransformação de monoterpenos por pseudomonas = Production of aroma compounds through biotransformation of monoterpenes by pseudomonas". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256734.
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Orientador: Gláucia Maria PastoreDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O aroma é responsável por grande parte do sabor de um alimento, e considerado um dos atributos mais importantes na aceitação do produto pelo consumidor. A preferência dos consumidores por produtos naturais tem incentivado o desenvolvimento de novos processos biotecnológicos para a produção de compostos de aroma naturais. A biotransformação de terpenos é uma alternativa promissora para a produção de aromas, visto que pode contornar alguns problemas associados a síntese química como a baixa geração de resíduos tóxicos e alta regio- e estéreo-seletividade das reações. Ademais, segundo a legislação brasileira, produtos obtidos por métodos microbiológicos podem ser rotulados como 'naturais' (ANVISA, Resolução nº 104, de 14 de maio de 1999). Os processos de biotransformação de monoterpenos frequentemente utilizam bactérias do gênero Pseudomonas como biocatalisadores por se adaptarem facilmente a diferentes substratos e condições extremas devido a sua elevada versatilidade metabólica e sistema enzimático complexo. Assim, o presente trabalho visou a utilização de monoterpenos (limoneno, a-pineno e citronelol) como substratos em processos de biotransformação por micro-organismos do gênero Pseudomonas. O Capítulo 1 apresenta um artigo de revisão atualizado sobre o potencial biotecnológico de micro-organismos do gênero Pseudomonas como biocatalisadores em processos de biotransformação. O Capítulo 2 refere-se aos resultados obtidos pelos experimentos que contemplam o isolamento de bactérias em meio seletivo e diferencial para Pseudomonas, e sua aplicação em processos de biotransformação de monoterpenos (R-(+)-limoneno, a-pineno, citronelol). Das 34 linhagens selecionadas, 9 bactérias foram capazes de biotransformar pelo menos um dos substratos em compostos de aroma de maior valor agregado. R-(+)-limoneno foi convertido a cis- e trans-carveol e carvona por 7 linhagens, atingindo concentrações de até 412 mg/L, 275 mg/L e 209 mg/L, respectivamente. a-Pineno, por sua vez, foi usado como fonte de carbono e energia por 7 linhagens e foi convertido principalmente em cis-verbenol e verbenona a baixas concentrações por 5 linhagens. Outros compostos como limoneno, mirtenol e ß-pineno, também foram identificados como produtos principais da conversão do a-pineno por 2 linhagens. Por outro lado, apenas 3 linhagens foram capazes de metabolizar citronelol em outros compostos derivados, como óxidos de rosa e isopulegol. O efeito da variação do pH do meio de biotransformação e da indução das linhagens, através da pré-exposição do micro-organismo ao substrato, no crescimento celular e formação de produtos de bioconversão foram avaliados com o intuito de otimizar o processo de biotransformação. A produção de óxido de rosa a partir de citronelol foi estudada e detalhada no capítulo final, que configurou um artigo publicado na revista Chemical Engineering Transactions. Em testes de citotoxicidade, a linhagem mostrou alta resistência a maiores concentrações de terpeno, revelando grande potencial para posterior otimização do processo. Os compostos derivados mais notáveis foram destacados no presente trabalho pela alta qualidade sensorial e alto valor agregado. Além das notas sensoriais altamente relevantes industrialmente, a carvona e o carveol são ainda reconhecidos por apresentar algumas funções biológicas. A verbenona e verbenol se destacam pelo alto custo e vasta aplicação nas áreas alimentícia, da agricultura, e da medicina. O óxido de rosa é um dos componentes mais importantes na criação de composições florais em perfumaria, além de possuir um baixo threshold. Sendo assim, a biotransformação de precursores de baixo custo em compostos de alto valor agregado pode ser considerado uma estratégia vantajosa e econômica
Abstract: Aroma compounds influence greatly the flavor of food products and govern their acceptance by consumers and market success. The increasing consumer preference for natural products has encouraged remarkable efforts towards the development of biotechnological processes for the production of natural flavor compounds. Biotransformation of terpenes represents a very promising alternative for production of aromas, since overcome the problems associated with chemical synthesis such as the low generation of toxic waste and high regio-and stereo-selectivity reactions. In addition, products obtained by microbiological methods can be labeled 'natural' under Brazilian law (ANVISA Resolution No. 104 dated May 14, 1999). Studies on monoterpene bioconversion frequently use bacteria from the genus Pseudomonas as biocatalysts since they adapt easily to different substracts and extreme conditions thanks to their high metabolic versatility and complex enzyme system. Therefore, the present work aims to use monoterpenes, such as limonene, a-pinene and citronellol, as substrate for the biotransformation processes by microorganisms from the genus Pseudomonas. The Chapter 1 presents a current review on the biotechnological potencial of microorganisms from the genus Pseudomonas. Chapter 2 refers to the results obtained from laboratory experiments which include the isolation of bacteria in selective and differential medium for Pseudomonas and their application in monoterpene biotransformation processes ((R-(+)-limonene, a-pinene, citronellol). Among 32 selected strains for investigation of biotransformation capability, 9 bacteria were able to biotransform one of the substrates on value-added flavor compounds. R-(+)-limonene was converted to cis- and trans-carveol and carvone by 7 strains, at concentrations of 412 mg/L, 275 mg/L e 209 mg/L, respectively. a-Pinene, in turn, was used as sole carbon and energy source for 7 strains, and yielded especially cis-verbenol and verbenone at low concentrations by 5 strains. Other compounds such as limonene, myrtenol and ß-pinene have also been identified as major products from the conversion of a-pinene by 2 strains. On the other hand, only 3 strains were able to metabolize citronelol on other derivative compounds, such as rose oxides and isopulegol. The effects of different pHof biotransformation medium and induction phase on cell growth and product concentration were evaluated in order to optimize the biotransformation process. The production of rose oxides by strain L1B2P was studied and detailed separately in the third chapter, set as a published article at Chemical Engineering Transactions. In citotoxicity tests, the strain showed impressive terpene resistance, revealing great potential for further process optimization. Most notable compound derivatives were highlighted in the present work due to their high sensory quality and added value. Besides highly industrially relevant sensory notes, carvone and carveol are also recognized by pursuing some biological functions. The verbenone and verbenol stand by the high cost and wide application in food, agriculture, and medicine fields. Rose oxide, in turn, is one of the most important components in creating floral compositions in perfumery, besides its low threshold. Thus, biotransformation of inexpensive precursors into high value added compounds can be considered an economical and advantageous strategy
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos
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Stewart, Hope Esther. "The development of a biogenic isoprene and monoterpene emission inventory for Great Britain". Thesis, Lancaster University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274259.
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Garbay, Justine. "Etude de l’arôme fruité des vins rouges via les interactions perceptives entre composés volatils d’intérêt dans le contexte de changement climatique pour le vignoble bordelais". Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0078.
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L’arôme fruité des vins rouges est décrit par une large gamme de descripteurs, allant des fruits frais aux fruits mûrs et confiturés, en passant par les fruits confits jusqu'aux notes de pruneaux. La qualité fruitée d’un vin rouge est décrite par des notes de fruits rouges et noirs frais et confiturés. Bien que de nombreux attributs sensoriels soient mentionnés dans la littérature, les connaissances concernant l'arôme fruité qualitatif des vins rouges par rapport à leur composition chimique nécessitent encore d'être approfondies. Cependant, au moins une composante de cette expression fruitée est le reflet d’interactions perceptives impliquant en majorité des esters, mais également d’autres familles de molécules aromatiques. Au cours de ces dernières années, des changements dans l’expression fruitée des vins rouges de Bordeaux, caractérisés par l’apparition des notes de fruits cuits et secs, ont été rapportés et corrélés au changement climatique. Ainsi, les techniciens du secteur vitivinicole et les scientifiques, soulignent la nécessité de prendre des précautions pour préserver l’arôme fruité frais des vins rouges de Bordeaux. Pour cela, une des stratégies d’adaptation consiste à introduire dans le vignoble bordelais des cépages tardifs sélectionnés pour leur cycle végétatif potentiellement adapté aux futures conditions climatiques. Cette thèse propose une meilleure compréhension de l’arôme fruité des vins rouges issus de cépages de Bordeaux, mais également de cépages cultivés autour du bassin méditerranéen, zone simulant les futures conditions climatiques de Bordeaux. Grâce à des approches sensorielles, il a été montré que des vins rouges de Bordeaux présentaient des similitudes avec des vins rouges issus de cépages implantés dans le pourtour méditerranéen au niveau de leur caractère fruité. Une caractérisation approfondie de la contribution des composés volatils d’intérêt dans la perception des notes fruitées a été réalisée. Des interactions perceptives entre des composés de la famille des monoterpènes et des C13-norisoprénoïdes en mélange avec des esters, ont révélé l’importance de ces composés dans la perception des notes fruitées. Enfin, l’addition de ces composés volatils dans un vin rouge montre une diminution des notes de fruits cuits et une augmentation des notes de fruits noirs frais. Ces travaux de recherche ouvrent de nouvelles perspectives en œnologie telles que la maîtrise des teneurs de ces composés d’intérêt par diverses pratiques, mais également la potentielle introduction des « nouveaux » cépages dans l’assemblage des vins de BordeauxThe fruity aroma of red wines is described by a wide range of descriptors, ranging from fresh fruits to ripe and jammy fruits, to candied fruits and prunes notes. The fruity quality of a red wine is characterized by notes of fresh and jammy red- and black-berry fruits. Although many sensory attributes are mentioned in the literature, knowledge regarding the qualitative fruity aroma of red wines in relation to their chemical composition still requires further investigation. However, at least one component of this fruity expression reflects perceptual interactions primarily involving esters, as well as other families of aromatic molecules. In recent years, changes in the fruity expression of Bordeaux red wines, characterized by the emergence of notes of cooked and dried fruits, have been reported and correlated with climate change. Thus, technicians in the wine industry and scientists emphasize the need to take precautions to preserve the fresh fruity aroma of Bordeaux red wines. One adaptation strategy involves introducing late-ripening grape varieties selected for their potentially suitable vegetative cycle under future climatic conditions into Bordeaux vineyard. This thesis proposes a better understanding of the fruity aroma of red wines derived from Bordeaux grape varieties, as well as those cultivated around the Mediterranean basin, simulating the future climatic conditions in Bordeaux. Through sensory approaches, it has been demonstrated that Bordeaux red wines exhibit similarities with red wines derived from grape varieties grown around the Mediterranean in terms of their fruity character. A detailed characterization of the contribution of volatile compounds of interest in the perception of fruity notes has been conducted. Perceptual interactions between compounds from the monoterpene and C13 norisoprenoid families, mixed with esters, have revealed the importance of these compounds in the perception of fruity notes. Finally, the addition of these volatile compounds to a red wine shows a decrease in cooked fruit notes and an increase in fresh black-berry fruits notes. This research opens up new perspectives in oenology, such as controlling the levels of these compounds of interest through various practices, as well as the potential introduction of "new" grape varieties into Bordeaux wine blends
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La, Rocca Viviana. "Atividade antinociceptiva do geraniol: estudos comportamentaise eletrofisiológicos". Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/9944.
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The high incidence of pain in the general population has encouraged research about this theme. Products derived from plant species have been widely used in the pharmacological treatment of pain relief. Recent studies have reported the important role of monoterpenes, active compounds found in the essential oils of aromatic plants, having relevant analgesic and anti-inflammatory potential. The geraniol (GER) is a monoterpenic alcohol, found in >160 essential oil of plant species, especially Cymbopogon gender. In the literature consulted, several biochemical and pharmacological properties are shown of GER: antitumor, antimicrobial, antiinflammatory, antioxidant, gastric and intestinal protector, neuroprotective and antiarrhythmic. In this study was evaluated the antinociceptive activity of GER, not yet reported, by animal behavioral and electrophysiological in vitro models. Male and female adult Swiss mice were used. Initially the acute toxicity of GER was investigated by calculating the lethal dose 50 (LD50) by intraperitoneal (i.p.) (= 199.9 mg/kg) and oral (p.o.) (> 1 g/kg). In psychopharmacological screening, after the administration of single doses of GER (i.p. and p.o.), behavioral changes were observed indicating a depressant profile on the central nervous system (CNS) and/or peripheral nervous system (SNP), and relevant antinociceptive effect of geraniol. Therefore, more specific antinociceptive property evaluation tests were performed. The GER (12.5, 25 or 50 mg/kg i.p. and 50 or 200 mg/kg p.o.) decreased (p<0.001) the number of abdominal contractions induced by i.p. injection of acetic acid, when compared with the control. The opioid antagonist naloxone (5 mg/kg) administered subcutaneously (s.c.) in mice, subsequently treated with GER (25 mg/kg i.p.), did not reverse its antinociceptive activity. The GER (12.5, 25 and 50 mg/kg i.p.) reduced (p<0.001) paw licking time in the second phase (15-30 min, inflammatory phase) of the formalin test. Also, in the glutamate test was reduced (p<0.01) paw licking time when GER 50 mg/kg i.p. administered. In a subsequent step, it was investigated the effect of GER on the excitability of peripheral nerve fibers through extracellular recording in the sciatic nerve in mice. The GER presented depressant effect of the compound action potential (CAP), which was reversed after washing and recovery period. The GER blocked components of the CAP concentration-dependent manner and exposure time to the drug: 1 mM after 120 min for the first component (Aγ and Aβ fibers) and 0.6 mM after 90 min for the second (Aγ and Aδ fibers). The concentration, which induces 50% inhibition of the peak-to-peak amplitude of the PAC (IC50) for the GER was calculated, being equal to 0.48±0.04 mM. The conduction velocity was also reduced by exposure to GER from the 0.3 mM concentration, for the 1st component [46.18±2.60 m/s to 36.04±1.60 m/s; p<0.05 (n=7)] and the 2nd component [18.37±1.31 m/s to 12.71±0.56 m/s; p<0.001 (n=7)]. In conclusion, the results obtained show that GER has antinociceptive activity, mainly in pain related to inflammation. Participation of the opioid pathway in its mechanism of action is unlikely, but the modulation of glutamatergic neurotransmission in a dose-dependent manner is a possible mechanism. Its antinociceptive activity is also related to the reduction in peripheral neuronal excitability, firstly in thinner fibers Aδ, which are directly connected to the conduction pain.
A elevada incidência da dor na população em geral tem incentivado as pesquisas entorno desse tema. Produtos oriundos de espécies vegetais têm sido amplamente utilizados no tratamento farmacológico de alívio da dor. Estudos recentes têm relatado o importante papel dos monoterpenos, princípios ativos encontrados nos óleos essenciais de plantas aromáticas, tendo relevante potencial analgésico e anti-inflamatório. O geraniol (GER) é um álcool monoterpênico, encontrado no óleo essencial de >160 espécies vegetais, especialmente do gênero Cymbopogon. Na literatura consultada, pesquisas apontam várias propriedades bioquímicas e farmacológicas para o GER: antitumoral, antimicrobiana, anti-inflamatória, antioxidante, de proteção gástrica e intestinal, neuroprotetora e antiarrítmica. Neste estudo foi avaliada a atividade antinociceptiva do GER, ainda não relatada, mediante modelos animais comportamentais e eletrofisiológicos in vitro. Foram utilizados camundongos machos e fêmeas Swiss adultos. Inicialmente, foi investigada a toxicidade aguda do GER mediante cálculo da dose letal 50 (DL50) pela via intraperitoneal (i.p.) (=199,9 mg/kg) e oral (v.o.) (>1 g/kg). Na triagem psicofarmacológica, após a subministração de doses únicas de GER (i.p. e v.o.) foram observadas alterações comportamentais que indicaram perfil depressor do sistema nervoso central (SNC) e/ou periférico (SNP), e relevante efeito antinociceptivo do geraniol. Portanto, foram realizados testes comportamentais de avaliação de propriedade antinociceptiva mais específicos. O GER (12,5; 25 e 50 mg/kg i.p. e 50 ou 200 mg/kg v.o.) reduziu (p<0,001) o número de contorções abdominais induzidas por injeção i.p. de ácido acético, quando comparado com o controle. O antagonista opióide naloxona (5 mg/kg) administrado pela via subcutânea (s.c.) em camundongos, subsequentemente tratados com GER (25 mg/kg i.p.), não reverteu sua atividade antinociceptiva. O GER (12,5; 25 e 50 mg/kg i.p.) reduziu (p<0,001) o tempo de lambida da pata na segunda fase (15-30 min, fase inflamatória) do teste da formalina. Também, no teste do glutamato houve redução (p<0,01) do tempo de lambida da pata quando administrado GER 50 mg/kg i.p. Em uma etapa subsequente, investigou-se o efeito do GER sobre a excitabilidade de fibras nervosas periféricas, mediante registro extracelular em nervo ciático de camundongo. O GER apresentou efeito depressor do potencial de ação composto (PAC), o qual foi parcialmente revertido após lavagem durante o período de recuperação. O GER bloqueou as componentes do PAC, de maneira dependente da concentração e do tempo de exposição à droga: 1 mM aos 120 min para a primeira componente (fibras Aγ e Aβ) e 0,6 mM aos 90 min para a segunda (fibras Aγ e Aδ). Foi calculada para o GER, a concentração que induz 50% de inibição da amplitude pico-a-pico do PAC (CI50), sendo igual a 0,48±0,04 mM. A velocidade de condução também, foi reduzida pela exposição ao GER, a partir da concentração de 0,3 mM para a 1ª componente [46,18±2,60 m/s para 36,04±1,60 m/s; p<0,05 (n=7)] e para a 2ª componente [18,37±1,31 m/s para 12,71±0,56 m/s; p<0,001 (n=7)]. Em conclusão, os resultados obtidos mostram que o GER tem atividade antinociceptiva, principalmente na dor relacionada à inflamação. A participação da via opióide no seu mecanismo de ação é pouco provável, mas a modulação da neurotransmissão glutamatérgica de maneira dependente da dose é um mecanismo possível. Sua atividade antinociceptiva tambèm, está relacionada à redução da excitabilidade neuronal periférica, primeiramente de fibras mais finas como Aδ, ligadas diretamente à condução da dor.
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Kahnt, Ariane [Verfasser], Hartmut [Akademischer Betreuer] Herrmann, Hartmut [Gutachter] Herrmann, Yoshiteru [Akademischer Betreuer] Iinuma y Thorsten [Gutachter] Hoffmann. "Semivolatile compounds from atmospheric monoterpene oxidation / Ariane Kahnt ; Gutachter: Hartmut Herrmann, Thorsten Hoffmann ; Hartmut Herrmann, Yoshiteru Iinuma". Leipzig : Universitätsbibliothek Leipzig, 2012. http://d-nb.info/1238150489/34.
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Kueh, Alona Swee Hua. "Molecular imprinting of small, poorly functionalised organic compounds". The University of Waikato, 2008. http://hdl.handle.net/10289/2264.
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Molecularly imprinted polymers (MIPs) have been compared to natural antibodies in that they can specifically bind target compounds in a similar way that antibodies specifically bind to an antigen. The attraction of the MIPs technology is the ease of creating binding elements which are relatively cheap compared with the process of isolating natural antibodies. In this research monoterpenes, such as α-terpineol, were chosen to be the model compounds for investigating the molecular imprinting of small, poorly functionalised organic compounds. The conventional non-covalent approach was mainly used to synthesise these MIPs, but the sacrificial-spacer semi-covalent approach was also investigated. A less widely used method, porogen-imprinting - a variant of non-covalent imprinting - was adapted for α-terpineol. The latter novel terpene MIP appeared to specifically bind α-terpineol, by hydrogen bonding, so the polymer was characterised in detail. The main parameters which were altered for preparing non-covalent MIPs included the template (α-terpineol, (-)-menthol or trans-terpin); the functional monomer (methacrylic acid, 2-hydroxyethyl methacrylate, bilirubin and phenol [for the semi-covalent MIP]); the cross-linking monomer (ethylene glycol dimethacrylate, divinylbenzene and trimethylolpropane trimethacrylate); and also the polymerisation method (block or precipitation polymerisation). The binding specificity and cross-reactivity for all the polymers were tested using a liquid batch-binding setup. The batch-binding setup required the detection of analyte that was not bound in order to calculate by difference the fraction of analyte bound to the polymer. Initially the terpenes were to be detected by a colorimetric method; however attempts to make the method sensitive and reliable were not successful. In comparison, gas chromatography was more reliable for the detection of terpenes and was used for the experiments presented in this thesis. 1H-NMR studies of the interaction between α-terpineol and acetic acid (as a non-polymerisable analogue of methacrylic acid) were investigated as a basis for understanding the binding to the carboxyl functional group moiety employed in many of the non-covalent MIPs that were made. The interaction between (-)-menthol and phenol was also investigated because the phenol moiety was employed in the semi-covalent MIP. Only selected MIPs, which appeared to specifically bind the template, were physically characterised. This included optimising the batch-binding parameters, scanning electron microscopy imaging, surface area and pore radius analysis and in some cases Fourier transform-infrared spectroscopy of the polymers.
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Bsaibes, Sandy. "Characterization of biogenic volatile organic compounds (BVOCs) and their OH reactivity in various agro-ecosystems". Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV093.
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Le radical hydroxyle OH est le principal oxydant dans la troposphère, mais ses puits restent encore difficiles à quantifier. L’un de ses principaux puits, est l’oxydation des Composés Organiques Volatils (COVs), composés provenant principalement de sources naturelles, à l’échelle du globe. Ils comprennent une grande variété d’espèces chimiques avec des réactivités très variables vis-à-vis des radicaux OH. Mesurer la réactivité OH totale, permet d’évaluer la charge en espèces réactives et d’estimer l’importance des espèces non mesurées/ non connues. Dans ce contexte, ce travail de thèse a d’abord visé d’optimiser la CRM ou « Comparative Reactivity Method », pour la mesure de la réactivité OH. Une fois les performances vérifiées, la CRM a été déployée dans deux écosystèmes : forestier et agricole. Les mesures de réactivité OH dans une forêt de pins maritimes ont montré des maximas de nuit arrivant jusqu’à 99 s-1 dans la canopée ; des niveaux se situant dans la limite supérieure de ce qui a été précédemment vu en sites forestiers. Des réactivités plus faibles, ne dépassant pas les 20- 30 s-1 en milieu de journée, ont été observées dans un champ agricole, en sortie d’une chambre dynamique de colza, en milieu de floraison. Dans ces deux écosystèmes, une différence a été trouvée entre la réactivité mesurée et celle calculée à partir des composés gazeux mesurés individuellement. Elle indique la présence d’une fraction manquante de composés primaires et secondaires non mesurés/ non identifiés. Ces travaux ont également mis en évidence l’importance de déterminer la spéciation des monoterpènes. Ceci nous a motivé à, optimiser et déployer un système de FastGC/ PTR-MS dans une forêt de chênes verts, ce qui nous a permis de suivre avec une haute résolution temporelle le cycle diurne des principaux monoterpènes, dont l’émission dépend du type de chêne ainsi que de la lumièreThe hydroxyl radical OH is the most powerful oxidant in the troposphere, however, characterizing its sinks remains a challenge. One important OH sink, is the oxidation of volatile organic compounds (VOCs), mainly released from biogenic sources, on the global scale. VOCs include a wide variety of chemical species with different lifetimes towards OH. Measuring OH reactivity is a useful tool to evaluate the loading in reactive species and to estimate the amplitude of unmeasured/unidentified compounds. In this context, this PhD work aimed to build and optimize a CRM or Comparative Reactivity method instrument for OH reactivity measurements. Afterwards, the CRM was deployed in a forest and an agricultural ecosystem. OH reactivity in a maritime pine forest showed maxima during night, reaching 99 s-1 inside the canopy, among the highest in forest environments. Relatively lower levels (max 20-30 s-1 at mid-day), were recorded from a dynamic chamber, during the blooming season of a rapeseed field. In these ecosystems, a difference was obtained between measured and calculated OH reactivity from measured compounds. It highlights the presence of a missing fraction of unmeasured primary and secondary compounds. These experiments demonstrate the importance of a detailed information on monoterpenes chemical speciation. In this perspective, a FastGC/PTR-MS system was optimized and deployed in a green oak forest. It allowed to monitor, with a fine time resolution, diurnal cyles of the main monoterpenes, which emissions are dependent on the tree type and on solar radiation
Libros sobre el tema "Monoterpenic compounds"
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Macaev, Fliur. Natural [alpha]-pinenes, carvones, 2- and 3-carenes as source of enantio-pure compounds. Chișinău: Academy of Sciences of Moldova, Institute of Chemistry, 2011.
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Saxton, J. Edwin. Chemistry of Heterocyclic Compounds - The Monoterpenoid Indole Alkaloids. Wiley & Sons, Incorporated, John, 2007.
Buscar texto completoCapítulos de libros sobre el tema "Monoterpenic compounds"
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Creasey, William A. "Pharmacology, Biochemistry, and Clinical Applications of the Monoterpenoid Alkaloids". En Chemistry of Heterocyclic Compounds: A Series Of Monographs, 783–829. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2008. http://dx.doi.org/10.1002/9780470186954.ch14.
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Kotzias, D., M. Duane, B. Nicollin y H. Schlitt. "Reaction of Monoterpene Hydrocarbons with O3, SO2 and NO2—Formation of Acidic Compounds". En Physico-Chemical Behaviour of Atmospheric Pollutants, 394–99. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0567-2_60.
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Rajhi, Imene, Bechir Baccouri, Fatma Rajhi, Moez Amri, Guido Flamini y Haythem Mhadhbi. "Monitoring the Aroma Compounds of Vicia faba L var. Major and var. Minor". En Case Studies of Breeding Strategies in Major Plant Species. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.106922.
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The volatile compounds of Vicia faba. L var. minor and var. major seeds were evaluated by headspace-solid phase micro-extraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The total identification percentages of the extracted volatiles were 95.5% and 98.3%, respectively. The number of aroma compounds detected was 28. Among them, 15 compounds were determined in the emission of whole legume seeds of minor cultivar and 22 from the major one. The volatiles were classified into five chemical classes, i.e., monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, apocarotenes, and non-terpene derivatives. Aldehydes and alkanes were considered as the most abundant constituents in non-terpene derivatives, followed by esters, alcohols, phenols, phenones, and hydrocarbons. A wide difference in term of volatiles was observed between major and minor faba bean cultivars. This study can provide useful information about the specific volatile characteristics for each cultivar and its possible use in the conception of legume-based ingredients and for pertinent breeding programs.
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Jedidi, Saber y Hichem Sebai. "Phytochemistry, Medicinal Uses, and Beneficial Nutritional Effects of Essential Oils". En Biochemistry. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.112696.
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Plants contain a considerable reservoir of secondary metabolites (flavonoids, tannins, and essential oils). These molecules exhibit variations in chemical structure as well as a very wide range of biological activities. Essential oils (EOs) are secondary metabolites produced by aromatic plants. EOs contain bioactive molecules, mainly represented by monoterpene hydrocarbons, oxygenated monoterpenes and sesquiterpenes, and sesquiterpene hydrocarbons. The organoleptic properties and biological activities of EOs are distinguished by their respective compositions. They have long been recognized for their medicinal properties such as antibacterial, antifungal, bioherbicide, antioxidant, anti-inflammatory, antidiabetic, and hepato-nephroprotective activities. These organic compounds also exert beneficial effects on the nutrition of ruminants, by modulating digestibility and reducing the emission of methane, a greenhouse gas. This chapter is devoted to the study of chemical composition, medicinal uses, and beneficial nutritional effects of essential oils.
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Valencia, Alexandra, Frank L. Romero-Orejon, Adriana Viñas-Ospino, Dayana Barriga-Rodriguez, Ana María Muñoz y Fernando Ramos-Escudero. "Sacha Inchi Seed (Plukenetia volubilis L.) Oil: Terpenoids". En Terpenes and Terpenoids - Recent Advances. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96690.
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Sacha inchi oil is a product obtained from oilseed (Plukenetia volubilis L.) and is an excellent source of bioactive compounds, especially in polyunsaturated fatty acids, tocopherols, and sterols. These compounds are causally related to their positive impact on human health. In this study summarizes some monoterpenes, sesquiterpenes, and triterpenes reported in Sacha inchi oil seeds and reviews their sensory properties. The terpenoids that characterize Sacha inchi seed oil are: α-pinene, sabinene, limonene, aristolene, cycloartenol, 24-methylene cycloartenol, lanosterol, β-sitosterol, stigmasterol, campesterol and phytol. The sensory properties of this oil are due to a set of volatile compounds including terpenoids, the odor descriptors of monoterpenes, sesquiterpenes and diterpenes are: flower, pine, turpentine, pepper, wood, lemon, orange, and sweet. These compounds were characterized by gas chromatography with different detectors.
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Carolina Cardoso-Teixeira, Ana, Klausen Oliveira-Abreu, Levy Gabriel de Freitas Brito, Andrelina Noronha Coelho-de-Souza y José Henrique Leal-Cardoso. "Effects of Terpenes and Terpenoids of Natural Occurrence in Essential Oils on Vascular Smooth Muscle and on Systemic Blood Pressure: Pharmacological Studies and Perspective of Therapeutic Use". En Terpenes and Terpenoids [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94194.
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Terpenes are a class of chemical compounds with carbon and hydrogen atoms in their structure. They can be classified into several classes according to the quantity of isoprene units present in its structure. Terpenes can have their structure modified by the addition of various chemical radicals. When these molecules are modified by the addition of atoms other than carbon and hydrogen, they become terpenoids. Terpenes and terpenoids come from the secondary metabolism of several plants. They can be found in the leaves, fruits, stem, flowers, and roots. The concentration of terpenes and terpenoids in these organs can vary according to several factors such as the season, collection method, and time of the day. Several biological activities and physiological actions are attributed to terpenes and terpenoids. Studies in the literature demonstrate that these molecules have antioxidant, anticarcinogenic, anti-inflammatory, antinociceptive, antispasmodic, and antidiabetogenic activities. Additionally, repellent and gastroprotective activity is reported. Among the most prominent activities of monoterpenes and monoterpenoids are those on the cardiovascular system. Reports on literature reveal the potential effect of monoterpenes and monoterpenoids on systemic blood pressure. Studies show that these substances have a hypotensive and bradycardic effect. In addition, the inotropic activity, both positive and negative, of these compounds has been reported. Studies also have shown that some monoterpenes and monoterpenoids also have a vasorelaxing activity on several vascular beds. These effects are attributed, in many cases to the blocking of ion channels, such as voltage-gated calcium channels. It can also be observed that monoterpenes and monoterpenoids can have their effects modulated by the action of the vascular endothelium. In addition, it has been shown that the molecular structure and the presence of chemical groups influence the potency and efficacy of these compounds on vascular beds. Here, the effect of several monoterpenes and monoterpenoids on systemic blood pressure and vascular smooth muscle will be reported.
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Rodríguez Valerón, Nabila, Diego Prado Vásquez y Rasmus Munk. "Pinaceae Species: Spruce, Pine and Fir as a New Culinary Herb and Spice". En Herbs and Spices - New Processing Technologies. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99280.
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The Pinaceae family has traditionally been used as medicine, resorted to as a famine food and for ornamental purposes as Christmas trees. In the last few years numerous restaurants have been using different species of Pinaceae family as a garnish or an aromatic spice, using them in different culinary applications like oils and infusions to flavor dressings and broths. Abies grandis (Grand fir), Pseudotsuga menziesii (Douglas fir), Pinus sylvestris (Scots pine) and Picea abies (Norway spruce) were researched on taxonomy, habitats and non-edible uses, culinary traditions, health and nutritional properties, aroma profile. The main compounds in Pinaceae family are monoterpenes, oxygenated monoterpenes, sesquiterpenes, oxygenate sesquiterpenes, diterpenes and hydrocarbons, especially α-β-pinene, limonene, α-terpinene, and even bornyl acetate, responsible for aroma compounds such as citrusy-, woody-, herbal-, or piney aromas. Modern gastronomy uses, sensory analysis and culinary applications were applied for demonstrating the possibilities on modern culinary application in this novel yet traditional spice.
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Mann, John. "Terpenoids and steroids—the isoprenoids". En Chemical Aspects of Biosynthesis. Oxford University Press, 1994. http://dx.doi.org/10.1093/hesc/9780198556763.003.0004.
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This chapter analyszes acetyl-SCoenzyme A, which is the main building block of the terpenoids and steroids. These contain diverse structures, such as α-pinene. The chapter recounts the establishment in the nineteenth century of the structures of the simple ten-carbon compounds or monoterpenes which contain an integral number of five-carbon units. It also mentions the pyrolysation of monoterpenes. This gives rise to isoprene as a major decomposition product. The chapter notes the importance of the biogenic speculation of isoprene as a building block in structural studies. The chapter considers HMG-CoA reductase as the most important enzyme as it catalyses the rate-determining step for the whole route to cholesterol. It explains how the inhibition of HMG-CoA reductase provides a viable strategy for lowering levels of cholesterol in the blood.
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Gebashe, Fikisiwe C., Adeyemi O. Aremu y Stephen O. Amoo. "Therapeutic Properties of Bioactive Secondary Metabolites in Essential Oil Crops". En Therapeutic Use of Plant Secondary Metabolites, 50–83. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815050622122010006.
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Medicinal herbs and their essential oils (EOs) are of commercial andindustrial importance with diverse uses as forage and fiber crops, in food, cosmetics,perfumery and chemical industries, and in traditional medicine due to theirphytochemical constituents and bioactivities. This chapter was aimed at documentingthe therapeutic properties of major secondary metabolites in EOs extracted from sixselected economically important medicinal herbs (Achillea millefolium L., Melissaofficinalis L., Origanum majorana L., Pelargonium graveolens L'Hér. Rosmarinusofficinalis L. and Thymus vulgaris L.). Forty-five compounds (mainly monoterpenes)were recorded as major compounds of the six medicinal herbs. The compounds possessvarying biological activities, which include antimicrobial, anti-inflammatory,antioxidant and cytotoxicity properties. Other activities reported were antinociceptive,neuroprotective effects, acetylcholinesterase inhibition, anti-ulcerogenic, DNAprotection, glutathione S-transferase activity, chemoprotective, anti-depressant andsedative effects. The compounds showed potential to be used as alternative agents asdrugs, cosmetic ingredients and food additives. Though some scientific evidence hasconfirmed the use of these herbs in various industries, much work still needs to be doneto comprehend the therapeutic application of their EOs and phytoconstituents to benefitfrom their full potential.
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Nay Win Tun, Khun, Nanik Siti Aminah, Alfinda Novi Kristanti, Hnin Thanda Aung y Yoshiaki Takaya. "Sesquiterpene from Myanmar Medicinal Plant (Curcuma comosa)". En Terpenes and Terpenoids [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93794.
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Curcuma comosa (Zingiberaceae) is widely grown in tropical and subtropical areas of Asia, like Thailand, Indonesia, Malaysia, and Myanmar. In Myanmar, the rhizome of Curcuma comosa is called Sa-nwin-ga, and local people had used it as a traditional medicine for stomach ache, diabetes mellitus, and hypertension. This species produces secondary metabolites of phenolic and nonphenolic groups. Phenolic groups like diarylheptanoids and flavonoids. While nonphenolics are terpenoids, especially sesqui- and monoterpenes. In this chapter, the group of sesquiterpene compounds from Curcuma comosa starts from the isolation technique, followed by the elucidation of the molecular structure, and their activity tests have been discussed.
Actas de conferencias sobre el tema "Monoterpenic compounds"
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Cojocari, Sergiu, Dmitri Bilan y Fliur Macaev. "Synthesis and structure of compounds obtained from the interaction of (+) 3-carene monoterpene with potassium permanganate". En Scientific seminar with international participation "New frontiers in natural product chemistry". Institute of Chemistry, Republic of Moldova, 2023. http://dx.doi.org/10.19261/nfnpc.2023.ab06.
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At present one of the main features of the chemistry of natural cyclopropanes is determined by the great diversity/variability of their structures and properties. However, the low content of most optically active cyclopropanes obtained from natural sources is a priority and requires the urgent development of readily applicable methods for synthesis from available natural substances, e.g. (+)-3-carene monoterpene 1. A distinctive structural feature of (+)-3-carene is the presence in its molecule of a bicyclic bridge system consisting of methylcyclohexane, 2,2dimethylcyclopropane moieties and a reactive С-С double bond. The main aim of the work is to obtain oxygen-containing functional groups in the (+)-3carene 1 molecule, thus the oxidation properties of (+)-3-carene with permanganate in an acetone solution were studied.It was found that after 3 hours of mixing of the reagents a mixture of products (TLC data) was formed, which allowed the isolation by SiO2 column chromatography of three predominant substances. Less polar was substance 2, in the IR spectrum of which there are characteristic stretching vibration frequencies for the unsaturated ketone (1660 cm-1), for methyl (1370 and 1385 cm-1). In the 1H NMR spectrum, the singlet signals of six protons and three protons of two single methyl groups in a strong field are complemented by one proton signals of three vinyl protons and a two proton signal of the methylene group. These data, combined with 13C NMR data, indicate the structure of (2Z,4Z)-3,6,6-trimethylcyclohepta-2,4-dienone 2. (1R,4S,6S)-4-hydroxy-4,7,7-trimethylbicyclo[4.1.0]heptane-3-one 3. The most polar substance was cis-diol (1S,3S,4R,6R)-3,7,7-trimethylbicyclo[4.1.0]heptan-33,4-diol 4. Thus, it was found that the interaction of monoterpene (+)-3-carene 1 with KMnO4 occurs with the introduction of both one and two oxygen-containing functional groups, and involves both change and conservation of the carene "scaffold".
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Stevanović, Kristina, Draginja Radošević, Vladimir Perović y Sanja Glišić. "Combined in silico approach to identify new terpenoid PPARα agonists". En 2nd International Conference on Chemo and Bioinformatics. Institute for Information Technologies, University of Kragujevac, 2023. http://dx.doi.org/10.46793/iccbi23.601s.
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In treating atherosclerosis and dyslipidemia, peroxisome proliferator-activated receptor alpha (PPARα) has been recognized as an interesting drug target. It is a ligand-activated transcriptional factor that controls genes involved in lipid metabolism regulation. The discovery of natural PPARα agonists may open new perspectives in its targeting. For several terpenoid molecules, it has been shown that they potentially activate PPARα. Linalool is a terpenoide molecule for which the PPARα antagonistic effect has been demonstrated in vivo. Here, we focused on searching for new terpenoid PPARα agonist candidates by proposing a simple theoretical criterion for fast virtual screening of TeroKit database. After in silico screening by using the EIIP/AQVN filter and through filtering of candidate compounds by ligand based virtual screening, natural monoterpenoid alcohol geraniol was selected as a promising candidate. Further, molecular docking was conducted to investigate its potential activation mechanisms, along with the reference molecule linalool. Despite observing low binding energies, the molecular docking results revealed potential insights into activation mechanisms of geraniol as well as reference molecule linalool.
Informes sobre el tema "Monoterpenic compounds"
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Lewinsohn, Efraim, Eran Pichersky y Shimon Gepstein. Biotechnology of Tomato Volatiles for Flavor Improvement. United States Department of Agriculture, abril de 2001. http://dx.doi.org/10.32747/2001.7575277.bard.
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The main objectives of the research project were: 1. The manipulation, by genetic engineering techniques, of the terpenoid pathway in tomato fruit. Specifically, to test the hypothesis whether overexpression of linalool synthase in tomato fruits will result in the diversion of intermediates of the carotene biosynthetic pathway to linalool, demonstrating that linalool synthase is a key regulatory enzyme, and possibly improving tomato flavor. 2. The elucidation of the biochemical pathway leading to eugenol and methyl eugenol, and the manipulation of this pathway to determine key enzymes and to improve flavor in tomato. Background, conclusions and implications The different proportions of volatile components present in foods often determine their flavor properties. Two of the ten most important flavor compounds in tomatoes, linalool and eugenol, are emitted by the flowers of Clarkia breweri, (Onagraceae), a plant native to California, and are also present in sweet basil (Ocimum basilicum, Lamiaceae). We have studied the key enzymes and genes involved in the production of these flavorants. Linalool synthase, the key enzyme in linalool biosynthesis and its corresponding gene were isolated and characterized from Clarkia breweri. The gene was coupled to a fruit-specific tomato promotor (E8) and was used to transform tomatoes. The transgenic tomatoes produced S-linalool and 1-hydroxylinalool, compounds absent from the fruits of controls. The transgenesis did not adversely affect the overall appearance of the plants nor the levels of other terpenoids present such as carotenoids and vitamin E. Our work has proven that the terpenoid pathway in tomatoes can be modified by the introduction and expression of foreign genes coding for the enzymes controlling the production of monoterpenoid flavor compounds. We have also isolated novel enzymes and genes that are involved in the formation of eugenol and methyl eugenol from Clarkia breweri and basil. An EST library of basil glandular trichomes (the site of eugenol and methyl eugenol biosynthesis) was prepared. More than 1,200 genes have been preliminary characterized and a few of them have been confirmed by functional expression, to be involved in eugenol and methyl eugenol biosynthesis. These genes have augmented the still small repertoire of genes that are available to modify the aroma of agricultural produce by genetic engineering.