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1
Soto, Ernesto R., Florentina Rus, Hanchen Li, Carli Garceau, Jeffrey Chicca, Mostafa Elfawal, David Gazzola et al. "Yeast Particle Encapsulation of Scaffolded Terpene Compounds for Controlled Terpene Release". Foods 10, n. 6 (27 maggio 2021): 1207. http://dx.doi.org/10.3390/foods10061207.
Testo completoAbstract (sommario):
Terpenes are naturally occurring compounds produced by plants that are of great commercial interest in the food, agricultural, cosmetic, and pharmaceutical industries due to their broad spectra of antibacterial, antifungal, anthelmintic, membrane permeation enhancement, and antioxidant biological activities. Applications of terpenes are often limited by their volatility and the need for surfactants or alcohols to produce stable, soluble (non-precipitated) products. Yeast particles (YPs) are hollow, porous microspheres that have been used for the encapsulation of terpenes (YP terpenes) by passive diffusion of terpenes through the porous YP cell walls. We here report the development of a second generation YP encapsulated terpene technology that incorporates the stimuli-responsive control of terpene release using biodegradable pro-terpene compounds (YP pro-terpenes). YP terpenes and YP pro-terpenes were both produced, in which high levels of carvacrol, eugenol, thymol and geraniol were encapsulated. The YP pro-terpenes show higher encapsulation stability than YP terpenes due to pro-terpenes being non-volatile solids at room temperature and stable in suspensions at neutral pH. YP pro-terpenes and YP terpenes were evaluated for biological activity in antibacterial, antifungal and anthelmintic assays. The YP pro-terpenes retained the full biological activity of the parent terpene compound.
2
Soto, Ernesto R., Florentina Rus e Gary R. Ostroff. "Yeast Particles Hyper-Loaded with Terpenes for Biocide Applications". Molecules 27, n. 11 (2 giugno 2022): 3580. http://dx.doi.org/10.3390/molecules27113580.
Testo completoAbstract (sommario):
Yeast particles (YPs) are 3–5 µm hollow and porous microspheres, a byproduct of some food grade yeast (Saccharomyces cerevisiae) extract manufacturing processes. Terpenes can be efficiently encapsulated inside YPs by passive diffusion through the porous cell walls. As previously published, this YP terpene encapsulation approach has been successfully implemented (1) to develop and commercialize fungicide and nematicide products for agricultural applications, (2) to co-load high potency agrochemical actives dissolved in terpenes or suitable solvents, and (3) to identify YP terpenes with broad-acting anthelmintic activity for potential pharmaceutical applications. These first-generation YP terpene materials were developed with a <2:1 terpene: YP weight ratio. Here we report methods to increase the terpene loading capacity in YPs up to 5:1 terpene: YP weight ratio. Hyper-loaded YP terpenes extend the kinetics of payload release up to three-fold compared to the commercialized YP terpene formulations. Hyper-loaded YP-terpene compositions were further optimized to achieve high terpene storage encapsulation stability from −20 °C to 54 °C. The development of hyper-loaded YP terpenes has a wide range of potential agricultural and pharmaceutical applications with terpenes and other compatible active substances that could benefit from a delivery system with a high payload loading capacity combined with increased payload stability and sustained release properties.
3
Niu, Yunwei, Xiaoxin Sun, Zuobing Xiao, Pinpin Wang e Ruolin Wang. "Olfactory Impact of Terpene Alcohol on Terpenes Aroma Expression in Chrysanthemum Essential Oils". Molecules 23, n. 11 (29 ottobre 2018): 2803. http://dx.doi.org/10.3390/molecules23112803.
Testo completoAbstract (sommario):
The key point of our work was evaluating the impact of terpene alcohols on the aroma expression of terpenes recombination in Chrysanthemum essential oils. Using pure commercial products, various aromatic recombinations were prepared, consisting of terpenes recombination and six terpene alcohols, all the concentrations found in Chrysanthemum essential oils. There were five groups of terpene alcohols mixtures performed very interesting with the addition or omission tests. The “olfactory threshold” of the terpenes recombination had a notable decrease when adding isoborneol, d-Fenchyl alcohol respectively through the Feller’s additive model analysis. Furthermore, the descriptive test indicated that the addition of terpene alcohols mixture had the different effect on fruity, floral, woody, green, and herbal aroma intensity. Specifically, when isoborneol was added to the terpenes recombination in squalane solution, it was revealed that isoborneol had a synergy impact on herbal and green notes of the terpenes recombination and masked the fruity note.
4
Nault, J. R., e Rene I. Alfaro. "Changes in cortical and wood terpenes in Sitka spruce in response to wounding". Canadian Journal of Forest Research 31, n. 9 (1 settembre 2001): 1561–68. http://dx.doi.org/10.1139/x01-082.
Testo completoAbstract (sommario):
Terpene levels were measured in bark and wood samples of Sitka spruce (Picea sitchensis (Bong.) Carrière) trees. The trees that had been selected as early or late flushing were subjected to artificial wounding to simulate attack by the white pine weevil, Pissodes strobi (Peck). Samples were taken at four times during the growing season: before wounding, shortly after wounding, and two times later in the season. Terpenes were extracted with hexane and quantified by capillary gas chromatography. There were no significant differences in total bark terpenes between early- and late-flushing trees or between control and wounded trees over all sampling times. There were no significant differences in total wood terpenes between early- and late-flushing trees or among sampling times, but a statistically significant difference was found between control and wounded trees. Eleven individual terpenes accounted for the majority of the terpenes in the extracts. Four bark terpenes showed significant differences with sampling time, two with flushing class, and none with treatment. Five wood terpenes showed significant differences with sampling time, two with flushing class, and nine with treatment. We concluded that flushing had only a minor effect on bark and wood terpene profiles and that wounding significantly increased terpene concentration in wood shortly after injury.
5
Weyerstahl, Peter, Helga Marschall-Weyerstahl, Josef Penninger e Lutz Walther. "Terpenes and terpene derivatives-22". Tetrahedron 43, n. 22 (gennaio 1987): 5287–98. http://dx.doi.org/10.1016/s0040-4020(01)87705-x.
Testo completo
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Liu, Jiajia, Man Lin, Penggang Han, Ge Yao e Hui Jiang. "Biosynthesis Progress of High-Energy-Density Liquid Fuels Derived from Terpenes". Microorganisms 12, n. 4 (30 marzo 2024): 706. http://dx.doi.org/10.3390/microorganisms12040706.
Testo completoAbstract (sommario):
High-energy-density liquid fuels (HED fuels) are essential for volume-limited aerospace vehicles and could serve as energetic additives for conventional fuels. Terpene-derived HED biofuel is an important research field for green fuel synthesis. The direct extraction of terpenes from natural plants is environmentally unfriendly and costly. Designing efficient synthetic pathways in microorganisms to achieve high yields of terpenes shows great potential for the application of terpene-derived fuels. This review provides an overview of the current research progress of terpene-derived HED fuels, surveying terpene fuel properties and the current status of biosynthesis. Additionally, we systematically summarize the engineering strategies for biosynthesizing terpenes, including mining and engineering terpene synthases, optimizing metabolic pathways and cell-level optimization, such as the subcellular localization of terpene synthesis and adaptive evolution. This article will be helpful in providing insight into better developing terpene-derived HED fuels.
7
Mirza, Zeynep, Ernesto R. Soto, Yan Hu, Thanh-Thanh Nguyen, David Koch, Raffi V. Aroian e Gary R. Ostroff. "Anthelmintic Activity of Yeast Particle-Encapsulated Terpenes". Molecules 25, n. 13 (27 giugno 2020): 2958. http://dx.doi.org/10.3390/molecules25132958.
Testo completoAbstract (sommario):
Soil-transmitted nematodes (STN) infect 1–2 billion of the poorest people worldwide. Only benzimidazoles are currently used in mass drug administration, with many instances of reduced activity. Terpenes are a class of compounds with anthelmintic activity. Thymol, a natural monoterpene phenol, was used to help eradicate hookworms in the U.S. South circa 1910. However, the use of terpenes as anthelmintics was discontinued because of adverse side effects associated with high doses and premature stomach absorption. Furthermore, the dose–response activity of specific terpenes against STNs has been understudied. Here we used hollow, porous yeast particles (YPs) to efficiently encapsulate (>95%) high levels of terpenes (52% w/w) and evaluated their anthelmintic activity on hookworms (Ancylostoma ceylanicum), a rodent parasite (Nippostrongylus brasiliensis), and whipworm (Trichuris muris). We identified YP–terpenes that were effective against all three parasites. Further, YP–terpenes overcame albendazole-resistant Caenorhabditis elegans. These results demonstrate that terpenes are broad-acting anthelmintics. Terpenes are predicted to be extremely difficult for parasites to resist, and YP encapsulation provides water-suspendable terpene materials without surfactants and sustained terpene release that could lead to the development of formulations for oral delivery that overcome fast absorption in the stomach, thus reducing dosage and toxic side effects.
8
Chenebault, Célia, Victoire Blanc-Garin, Marine Vincent, Encarnación Diaz-Santos, Amélie Goudet, Corinne Cassier-Chauvat e Franck Chauvat. "Exploring the Potential of the Model Cyanobacteria Synechococcus PCC 7002 and PCC 7942 for the Photoproduction of High-Value Terpenes: A Comparison with Synechocystis PCC 6803". Biomolecules 13, n. 3 (9 marzo 2023): 504. http://dx.doi.org/10.3390/biom13030504.
Testo completoAbstract (sommario):
We have performed the first comparative analysis of the potential of two physiologically-diverse model cyanobacteria, Synechococcus PCC 7002 (S.7002) and Synechococcus elongatus PCC 7942 (S.7942), for the photosynthetic production of four chemically-different high-value terpenes: two monoterpenes limonene and pinene, and two sesquiterpenes bisabolene and farnesene. We showed, for the first time, that S.7002 and S.7942 can produce farnesene and bisabolene, respectively. Both cyanobacteria produced farnesene (S.7942 produced more efficiently than S.7002) more efficiently than the other tested terpenes (especially pinene, the weakest produced terpene). S.7002 produced limonene more efficiently than bisabolene, whereas S.7942 produced bisabolene more efficiently than limonene. These findings suggest that S.7942 is better suited to produce sesquiterpenes than monoterpenes. Interestingly, higher levels of terpenes were produced by S.7942 and S.7002 expressing a terpene-synthase gene from both an RSF1010-derived replicating plasmid and a neutral chromosomal site, as compared to either the plasmid alone or the chromosome alone. These results suggest that in both cyanobacteria, the production of terpenes is more limited by the activity of terpene synthases than the abundance of terpene precursors. Finally, higher levels of terpenes were produced by S.7002 growing on urea (a frequent pollutant) as compared to nitrate or ammonium, the standard nitrogen sources for cyanobacteria.
9
Champagne, Emilie, Michaël Bonin, Alejandro A. Royo, Jean-Pierre Tremblay e Patricia Raymond. "Predicting terpene content in dried conifer shoots using near infrared spectroscopy". Journal of Near Infrared Spectroscopy 28, n. 5-6 (ottobre 2020): 308–14. http://dx.doi.org/10.1177/0967033520950516.
Testo completoAbstract (sommario):
Terpenes are phytochemicals found in multiple plant genera, especially aromatic herbs and conifers. Terpene content quantification is costly and complex, requiring the extraction of oil content and gas chromatography analyses. Near infrared (NIR) spectroscopy could provide an alternative quantitative method, especially if calibration can be developed with the spectra of dried plant material, which are easier and faster to acquire than oil-based spectra. Here, multispecies NIR spectroscopy calibrations were developed for total terpene content (mono- and sesquiterpenes) and for specific terpenes (α-pinene, β-pinene and myrcene) with five conifers species ( Picea glauca, Picea rubens, Pinus resinosa, Pinus strobus and Thuja occidentalis). The terpene content of fresh shoot samples was quantified with gas chromatography. The NIR spectra were measured on freeze-dried samples (n = 137). Using a subset of the samples, modified partial least squares regressions of total terpene and the three individual terpenes content were generated as a functions of the NIR spectra. The standard errors of the internal cross-validations (values between 0.25 and 2.28) and the ratio of prediction to deviation ratios (RPD values between 2.20 and 2.38) indicate that all calibrations have similar accuracy. The independent validations, however, suggest that the calibrations for total terpene and α-pinene content are more accurate (respective coefficient of determination: r2 = 0.85 and 0.82). In contrast, calibrations for β-pinene and myrcene had a low accuracy (respectively: r2 = 0.62 and 0.08), potentially because of the low concentration of these terpenes in the species studied. The calibration model fits (i.e., r2) are comparable to previously published calibration using the spectra of dried shoot samples and demonstrate the potential of this method for terpenes in conifer samples. The calibration method used could be useful in several other domains (e.g. seedling breeding program, industrial), because of the wide distribution of terpenes and especially of pinenes.
10
Sommano, Sarana Rose, Chuda Chittasupho, Warintorn Ruksiriwanich e Pensak Jantrawut. "The Cannabis Terpenes". Molecules 25, n. 24 (8 dicembre 2020): 5792. http://dx.doi.org/10.3390/molecules25245792.
Testo completoAbstract (sommario):
Terpenes are the primary constituents of essential oils and are responsible for the aroma characteristics of cannabis. Together with the cannabinoids, terpenes illustrate synergic and/or entourage effect and their interactions have only been speculated in for the last few decades. Hundreds of terpenes are identified that allude to cannabis sensory attributes, contributing largely to the consumer’s experiences and market price. They also enhance many therapeutic benefits, especially as aromatherapy. To shed light on the importance of terpenes in the cannabis industry, the purpose of this review is to morphologically describe sources of cannabis terpenes and to explain the biosynthesis and diversity of terpene profiles in different cannabis chemovars.
11
Chen, Xinlu, Marcin Nowicki, Phillip A. Wadl, Chi Zhang, Tobias G. Köllner, Miriam Payá‐Milans, Matthew L. Huff, Margaret E. Staton, Feng Chen e Robert N. Trigiano. "Chemical profile and analysis of biosynthetic pathways and genes of volatile terpenes in Pityopsis ruthii, a rare and endangered flowering plant". PLOS ONE 18, n. 6 (23 giugno 2023): e0287524. http://dx.doi.org/10.1371/journal.pone.0287524.
Testo completoAbstract (sommario):
It is critical to gather biological information about rare and endangered plants to incorporate into conservation efforts. The secondary metabolism of Pityopsis ruthii, an endangered flowering plant that only occurs along limited sections of two rivers (Ocoee and Hiwassee) in Tennessee, USA was studied. Our long-term goal is to understand the mechanisms behind P. ruthii’s adaptation to restricted areas in Tennessee. Here, we profiled the secondary metabolites, specifically in flowers, with a focus on terpenes, aiming to uncover the genomic and molecular basis of terpene biosynthesis in P. ruthii flowers using transcriptomic and biochemical approaches. By comparative profiling of the nonpolar portion of metabolites from various tissues, P. ruthii flowers were rich in terpenes, which included 4 monoterpenes and 10 sesquiterpenes. These terpenes were emitted from flowers as volatiles with monoterpenes and sesquiterpenes accounting for almost 68% and 32% of total emission of terpenes, respectively. These findings suggested that floral terpenes play important roles for the biology and adaptation of P. ruthii to its limited range. To investigate the biosynthesis of floral terpenes, transcriptome data for flowers were produced and analyzed. Genes involved in the terpene biosynthetic pathway were identified and their relative expressions determined. Using this approach, 67 putative terpene synthase (TPS) contigs were detected. TPSs in general are critical for terpene biosynthesis. Seven full-length TPS genes encoding putative monoterpene and sesquiterpene synthases were cloned and functionally characterized. Three catalyzed the biosynthesis of sesquiterpenes and four catalyzed the biosynthesis of monoterpenes. In conclusion, P. ruthii plants employ multiple TPS genes for the biosynthesis of a mixture of floral monoterpenes and sesquiterpenes, which probably play roles in chemical defense and attracting insect pollinators alike.
12
King, Drew J., Roslyn M. Gleadow e Ian E. Woodrow. "Terpene deployment in Eucalyptus polybractea; relationships with leafstructure, environmental stresses, and growth". Functional Plant Biology 31, n. 5 (2004): 451. http://dx.doi.org/10.1071/fp03217.
Testo completoAbstract (sommario):
Terpene deployment was examined in a population of Eucalyptus polybractea (R.Baker) trees. Eucalyptus polybractea is a terpene-accumulating species, which stores terpenes in oil glands beneath the leaf surface. Using regression analysis, we showed that leaf thickness, measured as leaf mass per area (LMA), influenced terpene content, apparently through regulation of gland dimensions, and thus, gland volume. We also examined how environmental factors affected terpene content through regulation of both LMA, and therefore, storage capacity, and the supply of resources for terpene synthesis. Neither water stress, measured using carbon isotope ratios as an indicator, nor nutrient stress, measured as foliar nitrogen and phosphorus content, accounted for observed variation in either terpene content or LMA. Phenolic content, measured as a possible competing carbon sink, did not account for variation in terpene content, and variation in environmental stresses could not account for differences in growth rate. However, both terpenes and total carbon-based secondary metabolites (terpenes and phenolics) showed positive correlations with growth, suggesting plants gain a growth advantage by deploying greater amounts of secondary metabolites.
13
Bisht, B. S., Harshita Bankoti e Tanuja Bharti. "A Review on Therapeutic Uses of Terpenoids". Journal of Drug Delivery and Therapeutics 11, n. 1-s (15 febbraio 2021): 182–85. http://dx.doi.org/10.22270/jddt.v11i1-s.4523.
Testo completoAbstract (sommario):
Terpenes are a huge and assorted class of natural mixes, created by an assortment of plants, especially conifers, other plants and by some insects. Terpenes regularly have a solid smell and may ensure the plants that produce them by deterring herbivores and by pulling in hunters and parasites of herbivores. Terpene are the essential constituents of the basic oils of numerous kinds of plan Essential oils are utilized generally as aromas in perfumery and for example, fragrant healing. Manufactured varieties and subsidiaries of regular terpenes extraordinarily extend the assortment of fragrances utilized in perfumery and flavors utilized in food added substances.
Keywords: Terpene, Medicinal, Therapeutic.
14
Lai Shi Min, Shereen, Sook Yee Liew, Nelson Jeng Yeou Chear, Bey Hing Goh, Wen-Nee Tan e Kooi Yeong Khaw. "Plant Terpenoids as the Promising Source of Cholinesterase Inhibitors for Anti-AD Therapy". Biology 11, n. 2 (14 febbraio 2022): 307. http://dx.doi.org/10.3390/biology11020307.
Testo completoAbstract (sommario):
Plant-derived terpenes are the prolific source of modern drugs such as taxol, chloroquine and artemisinin, which are widely used to treat cancer and malaria infections. There are research interests in recent years on terpene-derived metabolites (diterpenes, triterpenes and sesquiterpenes), which are believed to serve as excellent cholinesterase inhibitors. As cholinesterase inhibitors are the current treatment for Alzheimer’s disease, terpene-derived metabolites will have the potential to be involved in the future drug development for Alzheimer’s disease. Hence, a bibliographic search was conducted by using the keywords “terpene”, “cholinesterase” and “Alzheimer’s disease”, along with cross-referencing from 2011 to 2020, to provide an overview of natural terpenes with potential anticholinesterase properties. This review focuses on the extraction, chemical structures and anti-cholinesterase mechanisms of terpenes, which support and encourage future research on drug discovery and development in treating Alzheimer’s disease.
15
Zhao, Rui, Lihua Lu, Qingxing Shi, Jian Chen e Yurong He. "Volatile Terpenes and Terpenoids from Workers and Queens of Monomorium chinense (Hymenoptera: Formicidae)". Molecules 23, n. 11 (1 novembre 2018): 2838. http://dx.doi.org/10.3390/molecules23112838.
Testo completoAbstract (sommario):
Twenty-one volatile terpenes and terpenoids were found in Monomorium chinense Santschi (Hymenoptera: Formicidae), a native Chinese ant, by using headspace solid-phase microextraction (HS-SPME) coupled with gas-phase chromatography and mass spectrometry (GC-MS), which makes this ant one of the most prolific terpene producers in insect. A sesquiterpene with unknown structure (terpene 1) was the main terpene in workers and neocembrene in queens. Terpenes and terpenoids were detected in poison, Dufour’s and mandibular glands of both workers and queens. Worker ants raised on a terpene-free diet showed the same terpene profile as ants collected in the field, indicating that de novo terpene and terpenoid synthesis occurs in M. chinense.
16
Kemper, Katarina, Max Hirte, Markus Reinbold, Monika Fuchs e Thomas Brück. "Opportunities and challenges for the sustainable production of structurally complex diterpenoids in recombinant microbial systems". Beilstein Journal of Organic Chemistry 13 (8 maggio 2017): 845–54. http://dx.doi.org/10.3762/bjoc.13.85.
Testo completoAbstract (sommario):
With over 50.000 identified compounds terpenes are the largest and most structurally diverse group of natural products. They are ubiquitous in bacteria, plants, animals and fungi, conducting several biological functions such as cell wall components or defense mechanisms. Industrial applications entail among others pharmaceuticals, food additives, vitamins, fragrances, fuels and fuel additives. Central building blocks of all terpenes are the isoprenoid compounds isopentenyl diphosphate and dimethylallyl diphosphate. Bacteria like Escherichia coli harbor a native metabolic pathway for these isoprenoids that is quite amenable for genetic engineering. Together with recombinant terpene biosynthesis modules, they are very suitable hosts for heterologous production of high value terpenes. Yet, in contrast to the number of extracted and characterized terpenes, little is known about the specific biosynthetic enzymes that are involved especially in the formation of highly functionalized compounds. Novel approaches discussed in this review include metabolic engineering as well as site-directed mutagenesis to expand the natural terpene landscape. Focusing mainly on the validation of successful integration of engineered biosynthetic pathways into optimized terpene producing Escherichia coli, this review shall give an insight in recent progresses regarding manipulation of mostly diterpene synthases.
17
Raz, Noa, Aharon M. Eyal e Elyad M. Davidson. "Optimal Treatment with Cannabis Extracts Formulations Is Gained via Knowledge of Their Terpene Content and via Enrichment with Specifically Selected Monoterpenes and Monoterpenoids". Molecules 27, n. 20 (15 ottobre 2022): 6920. http://dx.doi.org/10.3390/molecules27206920.
Testo completoAbstract (sommario):
Differences between therapeutic effects of medical cannabis inflorescences and those of their extracts are generally attributed to the differences in administration form and in the resultant pharmacokinetics. We hypothesized that difference may further extend to the composition of the actually consumed drug. Cannabinoid and terpene contents were compared between commercial cannabis inflorescences (n = 19) and decarboxylated extracts (n = 12), and between inflorescences and decarboxylated extracts produced from them (n = 10). While cannabinoid content was preserved in the extracts, a significant loss of terpenes was evident, mainly in the more volatile monoterpenes and monoterpenoids (representing a loss of about 90%). This loss changes the total terpene content, the proportion of monoterpenes out of the total terpenes, and the monoterpene/cannabinoid ratio. Terpene deficiency might impair extracts’ pharmacological efficacy and might contribute to the patients’ preference to inflorescences-smoking. This argues against the validity of terms such as “whole plant” and “full spectrum” extracts and creates a misleading assumption that extracts represent the pharmacological profile of the sourced inflorescences. Furthermore, it reduces the diversity in extracts, such as loss of differences between sativa-type and indica-type. Enriching cannabis extracts with selected terpenes may provide a suitable solution, generating a safe, precise, and reproducible drug with tailored cannabinoid and terpene contents. Careful selection of terpenes to be added enables tailor-made extracts, adjusted for various medicinal aims and for different populations.
18
Mahamat Ahmat, Yacoub, Sara Madadi, Luc Charbonneau e Serge Kaliaguine. "Epoxidation of Terpenes". Catalysts 11, n. 7 (14 luglio 2021): 847. http://dx.doi.org/10.3390/catal11070847.
Testo completoAbstract (sommario):
Terpene epoxides are considered as potential primary intermediates in the synthesis of numerous green polymers including epoxy resins, polycarbonates, nonisocyanate polyurethanes and even some polyamides. In this chapter we describe recent efforts from our group to develop catalytic and noncatalytic processes for terpene epoxidation using a variety of oxidizing agents and process intensification methods. Most experimental tests deal with limonene epoxidation with applicability to some other terpenes also demonstrated.
19
Tarasova, Ekaterina V., Natalia A. Luchnikova, Victoria V. Grishko e Irina B. Ivshina. "Actinomycetes as Producers of Biologically Active Terpenoids: Current Trends and Patents". Pharmaceuticals 16, n. 6 (12 giugno 2023): 872. http://dx.doi.org/10.3390/ph16060872.
Testo completoAbstract (sommario):
Terpenes and their derivatives (terpenoids and meroterpenoids, in particular) constitute the largest class of natural compounds, which have valuable biological activities and are promising therapeutic agents. The present review assesses the biosynthetic capabilities of actinomycetes to produce various terpene derivatives; reports the main methodological approaches to searching for new terpenes and their derivatives; identifies the most active terpene producers among actinomycetes; and describes the chemical diversity and biological properties of the obtained compounds. Among terpene derivatives isolated from actinomycetes, compounds with pronounced antifungal, antiviral, antitumor, anti-inflammatory, and other effects were determined. Actinomycete-produced terpenoids and meroterpenoids with high antimicrobial activity are of interest as a source of novel antibiotics effective against drug-resistant pathogenic bacteria. Most of the discovered terpene derivatives are produced by the genus Streptomyces; however, recent publications have reported terpene biosynthesis by members of the genera Actinomadura, Allokutzneria, Amycolatopsis, Kitasatosporia, Micromonospora, Nocardiopsis, Salinispora, Verrucosispora, etc. It should be noted that the use of genetically modified actinomycetes is an effective tool for studying and regulating terpenes, as well as increasing productivity of terpene biosynthesis in comparison with native producers. The review includes research articles on terpene biosynthesis by Actinomycetes between 2000 and 2022, and a patent analysis in this area shows current trends and actual research directions in this field.
20
Jin, Jieyang, Shangrui Zhang, Mingyue Zhao, Tingting Jing, Na Zhang, Jingming Wang, Bin Wu e Chuankui Song. "Scenarios of Genes-to-Terpenoids Network Led to the Identification of a Novel α/β-Farnesene/β-Ocimene Synthase in Camellia sinensis". International Journal of Molecular Sciences 21, n. 2 (19 gennaio 2020): 655. http://dx.doi.org/10.3390/ijms21020655.
Testo completoAbstract (sommario):
Terpenoids play vital roles in tea aroma quality and plants defense performance determination, whereas the scenarios of genes to metabolites of terpenes pathway remain uninvestigated in tea plants. Here, we report the use of an integrated approach combining metabolites, target gene transcripts and function analyses to reveal a gene-to-terpene network in tea plants. Forty-one terpenes including 26 monoterpenes, 14 sesquiterpenes and one triterpene were detected and 82 terpenes related genes were identified from five tissues of tea plants. Pearson correlation analysis resulted in genes to metabolites network. One terpene synthases whose expression positively correlated with farnesene were selected and its function was confirmed involved in the biosynthesis of α-farnesene, β-ocimene and β-farnesene, a very important and conserved alarm pheromone in response to aphids by both in vitro enzymatic assay in planta function analysis. In summary, we provided the first reliable gene-to-terpene network for novel genes discovery.
21
Tomlin, Elizabeth S., John H. Borden e Harold D. Pierce. "Relationship Between Volatile Foliar Terpenes and Resistance of Sitka Spruce to the White Pine Weevil". Forest Science 43, n. 4 (1 novembre 1997): 501–8. http://dx.doi.org/10.1093/forestscience/43.4.501.
Testo completoAbstract (sommario):
Abstract Volatile foliar terpenes were compared both quantitatively and qualitatively among 20 provenances and 11 cloned genotypes of Sitka spruce (Picea sitchensis Bong [Carr.]) that had been classified as resistant or susceptible to the white pine weevil (Pissodes strobi [Peck]). On average, trees in resistant provenances had significantly lower content of ten terpenes than in susceptible provenances. One resistant clone had significantly higher foliar terpene content, and four resistant clones had significantly lower content than susceptible trees. Thus clonal resistance could be expressed respectively by repellency or lack of apparency. Canonical discriminant analysis revealed that several resistant clones, particularly from the Haney provenance, could be distinguished from others on the basis of their terpene profiles. While there was no clear relationship between terpene profile and resistance, these results suggest that there are probably multiple resistant "chemotypes," and that volatile foliar terpenes may be useful in identifying potentially resistant trees. For. Sci. 43(4):501-508.
22
Wei, Junchi, Yun Yang, Ye Peng, Shaoying Wang, Jing Zhang, Xiaobo Liu, Jianjun Liu, Beibei Wen e Meifeng Li. "Biosynthesis and the Transcriptional Regulation of Terpenoids in Tea Plants (Camellia sinensis)". International Journal of Molecular Sciences 24, n. 8 (8 aprile 2023): 6937. http://dx.doi.org/10.3390/ijms24086937.
Testo completoAbstract (sommario):
Terpenes, especially volatile terpenes, are important components of tea aroma due to their unique scents. They are also widely used in the cosmetic and medical industries. In addition, terpene emission can be induced by herbivory, wounding, light, low temperature, and other stress conditions, leading to plant defense responses and plant–plant interactions. The transcriptional levels of important core genes (including HMGR, DXS, and TPS) involved in terpenoid biosynthesis are up- or downregulated by the MYB, MYC, NAC, ERF, WRKY, and bHLH transcription factors. These regulators can bind to corresponding cis-elements in the promoter regions of the corresponding genes, and some of them interact with other transcription factors to form a complex. Recently, several key terpene synthesis genes and important transcription factors involved in terpene biosynthesis have been isolated and functionally identified from tea plants. In this work, we focus on the research progress on the transcriptional regulation of terpenes in tea plants (Camellia sinensis) and thoroughly detail the biosynthesis of terpene compounds, the terpene biosynthesis-related genes, the transcription factors involved in terpene biosynthesis, and their importance. Furthermore, we review the potential strategies used in studying the specific transcriptional regulation functions of candidate transcription factors that have been discriminated to date.
23
Januszek, Magdalena, e Łukasz Wajda. "The Analysis of Correlations Between Terpene Transformations and Fermentation Type of Apple Musts". Acta Universitatis Cibiniensis. Series E: Food Technology 26, n. 1 (1 giugno 2022): 99–108. http://dx.doi.org/10.2478/aucft-2022-0008.
Testo completoAbstract (sommario):
Abstract We measured the concentration of 13 terpenes in musts of 3 different apple cultivars fermented spontaneously, with Ethanol RED yeast (Saccharomyces cerevisiae) or Cider Yeast (Saccharomyces bayanus). Then we analysed obtained data with PCA with various packages in R to assess how different types of fermentation and apple cultivars affected terpene profile. The most informative results of PCA were obtained in ‘psych’ package and they indicated that there were groups of terpenes which concentrations increased simultaneously, while for some other groups the content of particular compounds was negatively correlated. This suggests that the first group of terpenes originated from different substrates while the latter group could be obtained from the same compound. Our findings indicated new possible pathways of terpene transformation, e.g. linalool, citral and geraniol could transform into one another. Moreover, the role of S. bayanus in those processes remains unclear and it requires further consideration.
24
Pfeiffer, T., O. Forberich e F. J. Comes. "The contribution of the ozonolysis of terpenes to tropospheric OH concentrations". Canadian Journal of Physics 79, n. 2-3 (1 febbraio 2001): 131–42. http://dx.doi.org/10.1139/p01-030.
Testo completoAbstract (sommario):
The recent finding that OH is formed as a direct product of the ozonolysis of terpenes is used to investigate the influence of this new OH source on the tropospheric OH budget applying model calculations. The results show that the OH production following UV photolysis of ozone leads to the main competition for ozonolysis at daytime. OH may increase considerably in its concentration as a result of the ozonolysis of terpenes at low photolysis frequencies, however, at high photolysis frequencies and moderate NOx concentrations this effect is reversed due to the fast reaction of OH with terpenes. At night ozone competes with NO3 in its reactions with the terpenes. Integrated over a full day of 24 h the terpene reactions lead to a source of OH in the troposphere. PACS No.: 82.40We
25
Zhu, Xue-min, Yu Li, Fei Xu, Wei Gu, Guo-jun Yan, Jie Dong e Jun Chen. "Skin Electrical Resistance Measurement of Oxygen-Containing Terpenes as Penetration Enhancers: Role of Stratum Corneum Lipids". Molecules 24, n. 3 (31 gennaio 2019): 523. http://dx.doi.org/10.3390/molecules24030523.
Testo completoAbstract (sommario):
The measurement of skin electrical resistance (SER) has drawn a great deal of attention for the rapid screening of transdermal penetration enhancers (PEs). However, the mechanisms underlying the SER measurement are still unclear. This study was to investigate the effects and mechanisms of seven oxygen-containing terpenes on the SER kinetics. Stratum corneum (SC) lipids were proved to play a key role in SER measurement. Then, the factors affecting the SER measurement were optimized. By the determination of SER kinetics, cyclic terpenes (1,8-cineole, terpinen-4-ol, menthol and α-terpineol) were demonstrated to possess higher enhancement ratio (ER) values compared with linear terpenes (linalool, geraniol and citral). For the first time, the linear correlation was found between ER of terpenes and the interaction energy of terpene–ceramide complexes revealed by molecular simulation. The attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis revealed that the effect of cyclic terpenes on SC lipid arrangement was obviously stronger than that of linear terpenes. In addition, by evaluating HaCaT skin cell viability, little difference was found between the toxicities of cyclic and linear terpenes. In conclusion, measurement of SER could be a feasible approach for the efficient evaluation of the PEs that mainly act on SC lipids.
26
Anand, Uma, Praveen Anand e Mikael Hans Sodergren. "Terpenes in Cannabis sativa Inhibit Capsaicin Responses in Rat DRG Neurons via Na+/K+ ATPase Activation". International Journal of Molecular Sciences 24, n. 22 (15 novembre 2023): 16340. http://dx.doi.org/10.3390/ijms242216340.
Testo completoAbstract (sommario):
Terpenes in Cannabis sativa exert analgesic effects, but the mechanisms are uncertain. We examined the effects of 10 terpenes on capsaicin responses in an established model of neuronal hypersensitivity. Adult rat DRG neurons cultured with neurotrophic factors NGF and GDNF were loaded with Fura2AM for calcium imaging, and treated with individual terpenes or vehicle for 5 min, followed by 1 µMol capsaicin. In vehicle treated control experiments, capsaicin elicited immediate and sustained calcium influx. Most neurons treated with terpenes responded to capsaicin after 6–8 min. Few neurons showed immediate capsaicin responses that were transient or normal. The delayed responses were found to be due to calcium released from the endoplasmic reticulum, as they were maintained in calcium/magnesium free media, but not after thapsigargin pre-treatment. Terpene inhibition of calcium influx was reversed after washout of medium, in the absence of terpenes, and in the presence of the Na+/K+ ATPase inhibitor ouabain, but not CB1 or CB2 receptor antagonists. Thus, terpenes inhibit capsaicin evoked calcium influx by Na+/K+ ATPase activation. Immunofluorescence showed TRPV1 co-expression with α1β1 Na+/K+ ATPase in most neurons while others were either TRPV1 or α1β1 Na+/K+ ATPase positive.
27
Li, Tuo, Ximeng Liu, Haoyu Xiang, Hehua Zhu, Xuan Lu e Baomin Feng. "Two-Phase Fermentation Systems for Microbial Production of Plant-Derived Terpenes". Molecules 29, n. 5 (2 marzo 2024): 1127. http://dx.doi.org/10.3390/molecules29051127.
Testo completoAbstract (sommario):
Microbial cell factories, renowned for their economic and environmental benefits, have emerged as a key trend in academic and industrial areas, particularly in the fermentation of natural compounds. Among these, plant-derived terpenes stand out as a significant class of bioactive natural products. The large-scale production of such terpenes, exemplified by artemisinic acid—a crucial precursor to artemisinin—is now feasible through microbial cell factories. In the fermentation of terpenes, two-phase fermentation technology has been widely applied due to its unique advantages. It facilitates in situ product extraction or adsorption, effectively mitigating the detrimental impact of product accumulation on microbial cells, thereby significantly bolstering the efficiency of microbial production of plant-derived terpenes. This paper reviews the latest developments in two-phase fermentation system applications, focusing on microbial fermentation of plant-derived terpenes. It also discusses the mechanisms influencing microbial biosynthesis of terpenes. Moreover, we introduce some new two-phase fermentation techniques, currently unexplored in terpene fermentation, with the aim of providing more thoughts and explorations on the future applications of two-phase fermentation technology. Lastly, we discuss several challenges in the industrial application of two-phase fermentation systems, especially in downstream processing.
28
Romero, Bastien, Catherine Fernandez, Caroline Lecareux, Elena Ormeño e Anne Ganteaume. "How terpene content affects fuel flammability of wildland–urban interface vegetation". International Journal of Wildland Fire 28, n. 8 (2019): 614. http://dx.doi.org/10.1071/wf18210.
Testo completoAbstract (sommario):
Among plant characteristics promoting flammability, terpenes have received little attention, especially regarding the vegetation surrounding housing. Here, mono-, sesqui- and diterpenes were screened in live and dead leaves of ornamental species found in wildland–urban interfaces (WUIs) of south-eastern France. Terpene content and composition were compared among species and between fuel types. Their influence on flammability was assessed through several variables and compared with that of leaf thickness and moisture content. Six of the 17 species examined contained terpenes. Terpene diversity and content differed among species but not between fuel types. Mono-, sesqui- and diterpenes (especially the highly concentrated compounds) were involved to varying degrees in both leaf and litter flammability. Their effects could be opposite according to the flammability variable and the fuel type considered. Leaf sesquiterpene content and litter total terpene content had the strongest influence on maximum combustion temperature; the former also mainly drove leaf flaming duration. The other flammability variables were more strongly associated with either moisture content or leaf thickness. Our findings highlight the idea that fire management in the WUI must also acknowledge the potential for ornamental species containing terpenes, such as Pinus halepensis, to affect fire behaviour.
29
Kotsinis, Vasileios, Alexandros Dritsoulas, Dionysios Ntinokas e Ioannis O. Giannakou. "Nematicidal Effects of Four Terpenes Differ among Entomopathogenic Nematode Species". Agriculture 13, n. 6 (29 maggio 2023): 1143. http://dx.doi.org/10.3390/agriculture13061143.
Testo completoAbstract (sommario):
Entomopathogenic nematodes (EPNs) have been studied for more than half a century, and employed for insect pest management using augmentation, conservation, and classical biological control approaches. As obligate lethal parasitoids of insect larvae, EPN navigate a chemically complex soil environment and interact with their insect hosts, plants, and each other. EPN responses to various terpenes, such as herbivore-induced plant volatiles, have the potential to enhance EPN efficacy through their attraction. However, several of the terpenes are currently being formulated as biological fungicides, insecticides, and acaricides for above- or below-ground applications. We conducted laboratory experiments to investigate the possible nematicidal effect of four terpenes, carvacrol, geraniol, eugenol, and thymol, to two heterorhabditids and two steinernematid species. Each terpene showed nematicidal activity against at least two of the four EPN species, with carvacrol showing the strongest activity and Heterorhabditis bacteriophora the highest sensitivity. Despite the high sensitivity of both heterorhabditids and near-zero sensitivity of the steinernematids to thymol, carvacrol, and eugenol, an increasing effect was observed when steinermatid nematodes were exposed to geraniol, and a decreasing effect for heterorhabditids, with H. bacteriophora exhibiting higher mortality than H. indica. The virulence of the nematodes towards fourth instar Galleria mellonella was also tested after exposure to the median lethal doses of each terpene. No significant difference in virulence was observed between nematodes that were exposed or not exposed to sublethal doses. The experiments suggest that the tested terpenes have a strong effect on EPN viability, which should be considered when combining the two approaches in IPM. The terpenes did not have a universal effect on all nematode species, which merits further investigation, while virulence tests suggest that sublethal doses of these terpenes have no effect on the host-killing performance of EPNs.
30
Fauss, Jürgen, Claudia Reinmuth e Matthias Weigl. "6 P-Cymene Formation by Oxidation of Cyclohexadiene Monoterpenes – a Pitfall in Air Sampling of Terpenes". Annals of Work Exposures and Health 67, Supplement_1 (1 maggio 2023): i18. http://dx.doi.org/10.1093/annweh/wxac087.046.
Testo completoAbstract (sommario):
Abstract It has been known for a long time that certain terpenes are sensitive to oxidation. Especially in the presence of small amounts, as is the case in the environment or indoors, changes occur due to UV light or ozone exposition. Various oxidized products have also been detected when sampling low terpene concentrations using Tenax® tubes and subsequent thermal desorption. Here we show that carrying out common air sampling of monoterpenes in the lower ppm range on charcoal tubes, the atmospheric oxygen is sufficient to oxidize the most sensitive terpenes to a considerable extent, forming almost exclusively p-cymene. As expected, the extent of aromatization was strongest in the terpenes with a double unsaturated ring system such as α- or γ-terpinene or α-phellandrene while p-menthene or limonene were not affected. We studied the influence of sampling time, temperature, humidity and storage time of the coated tubes. Simultaneously conducted experiments with thermal desorption in the ppb range showed a significantly reduced p-cymene formation compared to the activated charcoal results. Our findings were confirmed by air samples of terpenes taken during the grinding of nutmegs. The concentrations of p-cymene determined were significantly higher than the terpene pattern of nutmeg oil would have suggested. Thus, the detection of p-cymene during air sampling may be an artifact caused by the presence of cyclohexadiene monoterpenes. This is particularly important because p-cymene is often used as an internal standard in terpene analysis thus preventing its artifact formation from being noticed.
31
Nault, Jason R. "Site temperatures influence seasonal changes in terpene composition in Douglas-fir vegetative buds and current-year foliage". Canadian Journal of Forest Research 33, n. 11 (1 novembre 2003): 2269–73. http://dx.doi.org/10.1139/x03-151.
Testo completoAbstract (sommario):
Over a 3-year period (19982000), variations in terpene composition was measured in vegetative buds of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) from six sites varying in elevation and geographic location with sampling from early spring to midsummer. Eleven terpenes were found in virtually all samples (tricyclene, α-pinene, camphene, sabinene, β-pinene, myrcene, Δ-3-carene, limonene, β-phellandrene, terpinolene, and bornyl acetate) and represented an average of 87% of the total terpenes. In each year, composition of the terpene mix varied significantly (P [Formula: see text] 0.05) for all sites and dates, with some significant site and date interactions. Degree-day accumulations were calculated for all sites and years. Patterns of change in terpene composition between sites, areas, and years were strongly related to the temperature regimes associated with site and year.
32
Lee, Sangin, Eun Jae Kim, Eunjeong Kwon, Seo Jeong Oh, Mansoo Cho, Chul Min Kim, Wonwoong Lee e Jongki Hong. "Identification of Terpene Compositions in the Leaves and Inflorescences of Hybrid Cannabis Species Using Headspace-Gas Chromatography/Mass Spectrometry". Molecules 28, n. 24 (14 dicembre 2023): 8082. http://dx.doi.org/10.3390/molecules28248082.
Testo completoAbstract (sommario):
Although cannabidiol and tetrahydrocannabinol in Cannabis species exert their pharmacological effects via the endocannabinoid system, it is believed that other phytochemicals, particularly terpenes, can modulate therapeutic outcomes through the entourage effect. Therefore, to gain a better understanding of the pharmacological effects of Cannabis, obtaining information on phytochemical compositions, including mono-, di-, and sesqui-terpenes in Cannabis species is essential. Applying a sophisticated analytical method is indispensable. In this study, headspace-gas chromatography/mass spectrometry (HS-GC/MS) was employed to identify major terpenes in the leaves and inflorescences of hybrid Cannabis species. The incubation time and temperature conditions for HS-GC/MS were optimized. This method was successfully applied to the leaves (n = 9) and inflorescences (n = 7) of hybrid Cannabis species. A total of 26 terpenes in Cannabis species were detected, and six major components, such as α-pinene (9.8–2270 μg/g), β-pinene (2.6–930 μg/g), myrcene (0.7–17,400 μg/g), limonene (1.3–300 μg/g), β-caryophyllene (60–3300 μg/g), and α-humulene (40–870 μg/g), were quantified. Each sample showed different terpene compositions, but six major terpenes among all the terpenes detected were consistently found in both the leaves and inflorescences of hybrid Cannabis species. In this study, the six major terpenes’ potential in hybrid Cannabis species was evaluated as biomarkers to distinguish hybrid Cannabis species samples. This study contributes to a better understanding of the entourage effect of Cannabis-based botanical drugs.
33
Weyerstahl, Peter, e Ina Schwope. "Terpenes and terpene derivatives, XXXIV. Synthesis ofrac-porosadienone". Liebigs Annalen 1995, n. 1 (gennaio 1995): 191–93. http://dx.doi.org/10.1002/jlac.199519950126.
Testo completo
34
Bustos-Segura, Carlos, Shannon Dillon, Andras Keszei, William J. Foley e Carsten Külheim. "Intraspecific diversity of terpenes of Eucalyptus camaldulensis (Myrtaceae) at a continental scale". Australian Journal of Botany 65, n. 3 (2017): 257. http://dx.doi.org/10.1071/bt16183.
Testo completoAbstract (sommario):
Plants show a high degree of intraspecific variation in several traits including plant secondary metabolites. This variation can be influenced by genetic and environmental factors that result in geographical structure in their distribution. By growing plants from several populations in a controlled environment, we studied variation in foliar terpenes in Eucalyptus camaldulensis, which is the widest distributed eucalypt, with a large range both latitudinally and longitudinally. We found that the concentration of terpenes is highly variable among subspecies. We identified four chemotypes dominated by 1,8-cineole, γ-terpinene, α- and β-phellandrene. While the 1,8-cineole chemotype is abundant in all populations, the other three chemotypes are rare in the central area and the north-east of Australia. The γ-terpinene chemotype is mainly restricted to the north and west of Australia, whereas the α- and β-phellandrene chemotypes show an opposite distribution in the north and south of the continent. The annual mean temperature and humidity of the source populations correlate with the abundance of the dominant terpenes. We also tested the effects of elevated CO2 concentrations on the terpene concentration and found that elevated CO2 atmosphere reduces the overall accumulation of foliar terpenes. The results suggest that variation in terpene composition in E. camaldulensis can be influenced by environmental variables, mainly favouring the 1,8-cineole chemotype in arid locations.
35
Kainulainen, P., J. Oksanen, V. Palomäki, J. K. Holopainen e T. Holopainen. "Effect of drought and waterlogging stress on needle monoterpenes of Picea abies". Canadian Journal of Botany 70, n. 8 (1 agosto 1992): 1613–16. http://dx.doi.org/10.1139/b92-203.
Testo completoAbstract (sommario):
Monoterpenes were analysed in needles of clonal Picea abies (L.) Karst. exposed to drought and waterlogging. In drought-stressed trees the amounts of tricyclene, α-pinene, and camphene were significantly (p < 0.05) higher than in the control trees. In the drought treatment the total terpene concentration was also significantly (p < 0.05) higher. Waterlogging did not have significant effects on individual terpenes and total terpene concentration. However, multivariate redundancy analysis indicated that the effect of treatments on all the compounds simultaneously was not significant (p = 0.12). These results are discussed in terms of their potential impact on preferential selection of host plant by insects. Key words: drought, needles, Picea abies, terpenes, waterlogging.
36
Ji, Wensu, e Xiaoyue Ji. "Comparative Analysis of Volatile Terpenes and Terpenoids in the Leaves of Pinus Species—A Potentially Abundant Renewable Resource". Molecules 26, n. 17 (29 agosto 2021): 5244. http://dx.doi.org/10.3390/molecules26175244.
Testo completoAbstract (sommario):
Pinaceae plants are widely distributed in the world, and the resources of pine leaves are abundant. In the extensive literature concerning Pinus species, there is much data on the composition and the content of essential oil of leaves. Still, a detailed comparative analysis of volatile terpenes and terpenoids between different species is missing. In this paper, headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was used to determine the volatile terpenes and terpenoids of typical Pinus species in China. A total of 46 volatile terpenes and terpenoids were identified, and 12 common compounds were found, which exhibited a great diversity in the leaves of Pinus species. According to the structures and properties of the compounds, all those compounds can be classified into four categories, namely monoterpenes, oxygenated terpenes, terpene esters, and sesquiterpenes. The results of principal component analysis and cluster analysis showed that the leaves of the six Pinus species could be divided into two groups. The species and contents of volatile terpenes and terpenoids in the leaves were quite different. The results not only provide a reference for the utilization of pine leaves resource, but also bring a broader vision on the biodiversity.
37
Wei, Qiuhui, Kaer Lan, Yuyang Liu, Rong Chen, Tianyuan Hu, Shujuan Zhao, Xiaopu Yin e Tian Xie. "Transcriptome analysis reveals regulation mechanism of methyl jasmonate-induced terpenes biosynthesis in Curcuma wenyujin". PLOS ONE 17, n. 6 (23 giugno 2022): e0270309. http://dx.doi.org/10.1371/journal.pone.0270309.
Testo completoAbstract (sommario):
Curcuma wenyujin is the source plant of three traditional Chinese medicines, which have been widely used in clinical treatment over 1000 years. The content of terpenes, the major medicinal active ingredients, is relatively low in this plant. Studies have shown that MeJA can promote terpenes biosynthesis in plants. However, the mechanism underlying the effect of MeJA in C. wenyujin remains unclear. In this work, the transcriptome of C. wenyujin leaves with MeJA treatment was analyzed to elucidate the regulation mechanism of MeJA-mediated terpene biosynthesis. Based on the RNA-seq data, 7,246 unigenes were differentially expressed with MeJA treatment. Expression pattern clustering of DEGs revealed that unigenes, related to JA biosynthesis and signal transduction, responded to exogenous MeJA stimulation on the early stage and maintained throughout the process. Subsequently, unigenes related to terpene biosynthesis pathway showed a significant up-regulation with 6 h treatment. The analysis results suggested that MeJA induced the expression of JA biosynthesis genes (such as LOXs, AOSs, AOCs, OPRs, and MFPs) and JA signal transduction core genes (JAZs and MYCs) to activate JA signaling pathway. Meanwhile, downstream JA-responsive genes presented up-regulated expression levels such as AACT, HMGSs, HMGRs, DXSs, DXRs, MCTs, HDSs, and HDRs, thus promoting terpenes biosynthesis. The transcriptional expressions of these genes were validated by qRT-PCR. In addition, six CwTPS genes in response to MeJA were identified. With MeJA treatment, the expression levels of CwTPSs were increased as well as those of the transcription factors MYB, NAC, bZIP, WRKY, AP2/ERF, and HLH. These TFs might potentially regulate terpenes biosynthesis. These results provide insights for regulation mechanism of terpenes biosynthesis.
38
Mahizan, Nik Amirah, Shun-Kai Yang, Chew-Li Moo, Adelene Ai-Lian Song, Chou-Min Chong, Chun-Wie Chong, Aisha Abushelaibi, Swee-Hua Erin Lim e Kok-Song Lai. "Terpene Derivatives as a Potential Agent against Antimicrobial Resistance (AMR) Pathogens". Molecules 24, n. 14 (19 luglio 2019): 2631. http://dx.doi.org/10.3390/molecules24142631.
Testo completoAbstract (sommario):
The evolution of antimicrobial resistance (AMR) in pathogens has prompted extensive research to find alternative therapeutics. Plants rich with natural secondary metabolites are one of the go-to reservoirs for discovery of potential resources to alleviate this problem. Terpenes and their derivatives comprising of hydrocarbons, are usually found in essential oils (EOs). They have been reported to have potent antimicrobial activity, exhibiting bacteriostatic and bactericidal effects against tested pathogens. This brief review discusses the activity of terpenes and derivatives against pathogenic bacteria, describing the potential of the activity against AMR followed by the possible mechanism exerted by each terpene class. Finally, ongoing research and possible improvisation to the usage of terpenes and terpenoids in therapeutic practice against AMR are discussed.
39
Yang, Limeng, Huan Liu, Yuhan Jin, Junfeng Liu, Li Deng e Fang Wang. "Recent Advances in Multiple Strategies for the Synthesis of Terpenes by Engineered Yeast". Fermentation 8, n. 11 (8 novembre 2022): 615. http://dx.doi.org/10.3390/fermentation8110615.
Testo completoAbstract (sommario):
Terpenes are an important class of natural secondary metabolites with a wide range of applications in food, pharmaceuticals, and biofuels. Currently, the traditional production methods of terpenes almost depend on plant extraction and chemical conversion. The plant extraction method consumes a lot of natural resources and makes it difficult to separate the target compound from the extractives, while the chemical conversion method has a complex synthesis route and leads to severe environmental pollution. Compared to plant extraction and chemical conversion methods, the microbial synthesis method has the advantages of preferable sustainability, low production cost and environmental friendliness, and is a potential way to achieve efficient terpenes production in the future. Yeast is a conventional platform for bio-chemical production and is also engineered to synthesize terpenes due to their abundant intracellular acetyl-CoA, high metabolic flux of the MVA pathway, high local concentrations of substrates and enzymes, and fewer by-products. At present, a variety of terpenes including α-farnesene, squalene, limonene, β-carotene have been successfully synthesized by the engineered yeast via the application of multiple strategies. This work summarized the progress of research on these strategies conducted in the synthesis of terpenes from several aspects, including the adaptive screening and expression of terpene synthases, the regulation of synthesis pathways, and the application of intracellular compartmentalized expression strategy. The perspectives and challenges were also discussed, from which it was hoped that some useful views for future research on the synthesis of terpenes in yeast would be provided.
40
Harwood, Stephen J., Maximilian D. Palkowitz, Cara N. Gannett, Paulo Perez, Zhen Yao, Lijie Sun, Héctor D. Abruña, Scott L. Anderson e Phil S. Baran. "Modular terpene synthesis enabled by mild electrochemical couplings". Science 375, n. 6582 (18 febbraio 2022): 745–52. http://dx.doi.org/10.1126/science.abn1395.
Testo completoAbstract (sommario):
The synthesis of terpenes is a large field of research that is woven deeply into the history of chemistry. Terpene biosynthesis is a case study of how the logic of a modular design can lead to diverse structures with unparalleled efficiency. This work leverages modern nickel-catalyzed electrochemical sp 2 –sp 3 decarboxylative coupling reactions, enabled by silver nanoparticle–modified electrodes, to intuitively assemble terpene natural products and complex polyenes by using simple modular building blocks. The step change in efficiency of this approach is exemplified through the scalable preparation of 13 complex terpenes, which minimized protecting group manipulations, functional group interconversions, and redox fluctuations. The mechanistic aspects of the essential functionalized electrodes are studied in depth through a variety of spectroscopic and analytical techniques.
41
Hosseini, Morteza, e David M. Pereira. "The Chemical Space of Terpenes: Insights from Data Science and AI". Pharmaceuticals 16, n. 2 (29 gennaio 2023): 202. http://dx.doi.org/10.3390/ph16020202.
Testo completoAbstract (sommario):
Terpenes are a widespread class of natural products with significant chemical and biological diversity, and many of these molecules have already made their way into medicines. In this work, we employ a data science-based approach to identify, compile, and characterize the diversity of terpenes currently known in a systematic way, in a total of 59,833 molecules. We also employed several methods for the purpose of classifying terpene subclasses using their physicochemical descriptors. Light gradient boosting machine, k-nearest neighbours, random forests, Gaussian naïve Bayes and Multilayer perceptron were tested, with the best-performing algorithms yielding accuracy, F1 score, precision and other metrics all over 0.9, thus showing the capabilities of these approaches for the classification of terpene subclasses. These results can be important for the field of phytochemistry and pharmacognosy, as they allow the prediction of the subclass of novel terpene molecules, even when biosynthetic studies are not available.
42
Chen, Xinlu, Tobias G. Köllner, Qidong Jia, Ayla Norris, Balaji Santhanam, Patrick Rabe, Jeroen S. Dickschat, Gad Shaulsky, Jonathan Gershenzon e Feng Chen. "Terpene synthase genes in eukaryotes beyond plants and fungi: Occurrence in social amoebae". Proceedings of the National Academy of Sciences 113, n. 43 (7 ottobre 2016): 12132–37. http://dx.doi.org/10.1073/pnas.1610379113.
Testo completoAbstract (sommario):
Terpenes are structurally diverse natural products involved in many ecological interactions. The pivotal enzymes for terpene biosynthesis, terpene synthases (TPSs), had been described only in plants and fungi in the eukaryotic domain. In this report, we systematically analyzed the genome sequences of a broad range of nonplant/nonfungus eukaryotes and identified putative TPS genes in six species of amoebae, five of which are multicellular social amoebae from the order of Dictyosteliida. A phylogenetic analysis revealed that amoebal TPSs are evolutionarily more closely related to fungal TPSs than to bacterial TPSs. The social amoeba Dictyostelium discoideum was selected for functional study of the identified TPSs. D. discoideum grows as a unicellular organism when food is abundant and switches from vegetative growth to multicellular development upon starvation. We found that expression of most D. discoideum TPS genes was induced during development. Upon heterologous expression, all nine TPSs from D. discoideum showed sesquiterpene synthase activities. Some also exhibited monoterpene and/or diterpene synthase activities. Direct measurement of volatile terpenes in cultures of D. discoideum revealed essentially no emission at an early stage of development. In contrast, a bouquet of terpenes, dominated by sesquiterpenes including β-barbatene and (E,E)-α-farnesene, was detected at the middle and late stages of development, suggesting a development-specific function of volatile terpenes in D. discoideum. The patchy distribution of TPS genes in the eukaryotic domain and the evidence for TPS function in D. discoideum indicate that the TPS genes mediate lineage-specific adaptations.
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Lourencon, Raquel, Steven P. Hart, Terry A. Gipson, Bob Adams e Davila Rassi. "192 Terpenes as antinutritive chemicals in red cedar". Journal of Animal Science 97, Supplement_1 (luglio 2019): 77. http://dx.doi.org/10.1093/jas/skz053.175.
Testo completoAbstract (sommario):
Abstract At some research sites goats aggressively consumed red cedar (Juniperus virginiana) throughout the year, while at other sites goats consumed little cedar, although they consumed more cedar in winter. It was hypothesized that differences in red cedar intake may be caused by terpenes. The purpose of this study was to measure terpenes in cedar needles at different locations and times of the year. Ninety-one samples of red cedar needles were obtained from four locations (Langston, OK; Midwest City, OK; Mannford, OK; Neosho, MO) at monthly intervals over a 2-yr period. Needles were manually stripped from branches at approximately 1.5 m high from at least 25 plants at each location. Sixty grams of cedar needles were extracted by steam distillation for 2 h. Some samples were exhaustively extracted for a further 6 h to calculate recovery (45.7%). Two mL of diethyl ether were added, containing 1 mg/mL of methyl decanoate (internal standard), samples were vortexed and the ether was dried with a stream of nitrogen. Samples were subjected to gas chromatography for terpenes. The total amount of terpenes (mg/g DM) was calculated as the sum of peak areas/peak area of the internal standard x 2 mg internal standard/ 0.457/ dried weight of cedar needles. Months were categorized as season. Data were analyzed using the SAS GLM procedure with factors of season, year, and location. Neither season (P > 0.8) nor location (P > 0.25) nor the interaction (P > .9) were significant factors determining total terpene content of red cedar. Concentration of total terpenes for Langston was 20.8, Mannford 18.4, Neosho 15.2, and OKC 18.6 mg/g DM. Concentration by season was Fall 17.1, Spring 18.6, Summer 17.5, and Winter 19.7 mg/g DM. Total terpene concentration does not seem to be a factor affecting red cedar consumption by goats.
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Miao, Wen, Jiaqiang Luo, Junda Liu, Kate Howell e Pangzhen Zhang. "The Influence of UV on the Production of Free Terpenes in Vitis vinifera cv. Shiraz". Agronomy 10, n. 9 (20 settembre 2020): 1431. http://dx.doi.org/10.3390/agronomy10091431.
Testo completoAbstract (sommario):
Terpenes contribute to the desirable flavour and aroma of grapes and wine. The biosynthesis of these plant secondary metabolites is influenced by both physiological and environmental factors, such as grapevine phenological stage and sunlight exposure. In this study, we investigated the influence of ultraviolet (UV) at different grapevine phenological stages on free terpenes in grape at harvest. Two types of transparent polymer films were applied to grape bunches to eliminate both UV-A and UV-B or only eliminate UV-B, followed by the identification and quantification of terpenes using headspace solid-phase microextraction with gas chromatography–mass spectrometry (HS–SPME–GC–MS) analysis. In all, 27 free terpenes were identified, including eight monoterpenes/monoterpenoids, four norisoprenoids and fifteen sesquiterpenes. Higher concentrations of γ-terpinene, linalool and β-damascenone were observed in grapes with UV-B attenuation compared to the naturally exposed grape bunches. Elevated α-muurolene was observed in UV-attenuated grapes from pre-veraison to harvest, while higher concentrations of γ-cadinene were observed in naturally exposed grapes. The impacts of UV exclusion on grape terpenes at harvest were specific to phenological stages, where applying UV films from veraison to intermediate ripeness reduced the concentrations of key terpenes in grape harvest and UV attenuation from intermediate ripeness to harvest promoted the accumulation of α-muurolene and γ-cadinene. This study provides information for viticulturists to better manage grape terpene composition through UV shading.
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L. Simakova, Irina, Andrey V. Simakov e Dmitry Yu. Murzin. "Valorization of Biomass Derived Terpene Compounds by Catalytic Amination". Catalysts 8, n. 9 (29 agosto 2018): 365. http://dx.doi.org/10.3390/catal8090365.
Testo completoAbstract (sommario):
This review fills an apparent gap existing in the literature by providing an overview of the readily available terpenes and existing catalytic protocols for preparation of terpene-derived amines. To address the role of solid catalysts in amination of terpenes the same reactions with homogeneous counterparts are also discussed. Such catalysts can be considered as a benchmark, which solid catalysts should match. Although catalytic systems based on transition metal complexes have been developed for synthesis of amines to a larger extent, there is an apparent need to reduce the production costs. Subsequently, homogenous systems based on cheaper metals operating by nucleophilic substitution (e.g., Ni, Co, Cu, Fe) with a possibility of easy recycling, as well as metal nanoparticles (e.g., Pd, Au) supported on amphoteric oxides should be developed. These catalysts will allow synthesis of amine derivatives of terpenes which have a broad range of applications as specialty chemicals (e.g., pesticides, surfactants, etc.) and pharmaceuticals. The review will be useful in selection and design of appropriate solid materials with tailored properties as efficient catalysts for amination of terpenes.
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Du, Zhihui, Xiyu Yang, Shuting Zhou, Yuxuan Jin, Weize Wang, Kuaifei Xia e Zhilin Chen. "Aromatic Terpenes and Their Biosynthesis in Dendrobium, and Conjecture on the Botanical Perfumer Mechanism". Current Issues in Molecular Biology 45, n. 7 (25 giugno 2023): 5305–16. http://dx.doi.org/10.3390/cimb45070337.
Testo completoAbstract (sommario):
This review presents a systematic analysis of the studies on volatiles in Dendrobium. Among the various components, aromatic terpenes are a crucial component in the development of the aromatic characteristics of Dendrobium and other plants. Recent advancements in detection and sequencing technology have resulted in a considerable rise in research on the biosynthetic processes of aromatic terpenes in Dendrobium and other flowering plants. Nevertheless, the inquiry into the precise means by which plants regulate the proportion of diverse aromatic terpenes in their floral scent, thereby preserving their olfactory traits, requires further investigation. A conjecture on the botanical perfumer mechanism, which condensed the findings of earlier studies, was put forward to address this area of interest. Specific transcription factors likely govern the coordinated expression of multiple key terpene synthase (TPS) genes during the flowering stage of plants, thereby regulating the proportional biosynthesis of diverse aromatic terpenes and sustaining the distinctive aromatic properties of individual plants. This review serves as a significant theoretical reference for further investigations into aromatic volatile compounds in Dendrobium.
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Makowski, Mathias, e Martin Ohlmeyer. "Influences of hot pressing temperature and surface structure on VOC emissions from OSB made of Scots pine". Holzforschung 60, n. 5 (1 agosto 2006): 533–38. http://dx.doi.org/10.1515/hf.2006.088.
Testo completoAbstract (sommario):
Abstract Oriented strand board (OSB) made of Scots pine (Pinus sylvestris L.) releases high amounts of terpenes and aldehydes. These volatile organic compound (VOC) emissions are clearly affected by the manufacturing parameters. As a consequence of high temperatures during hot pressing, terpene emissions from OSB are reduced. Aldehyde emissions are initially lowered after pressing at a high temperature (260°C). Furthermore, emissions are influenced by the surface structure. If the surface consists of fine particles, terpene emissions are lowered and the course of aldehyde formation is altered. Nevertheless, a reduction in VOC emissions by adjustment of the parameters investigated in this work seems to be restricted to terpenes. Aldehyde emissions from all panels converge during emission testing and in the final stages no clear distinction is possible according to the pressing temperature or surface structure.
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He, Xueying, Huan Wang, Jinfen Yang, Ke Deng e Teng Wang. "RNA sequencing on Amomum villosum Lour. induced by MeJA identifies the genes of WRKY and terpene synthases involved in terpene biosynthesis". Genome 61, n. 2 (febbraio 2018): 91–102. http://dx.doi.org/10.1139/gen-2017-0142.
Testo completoAbstract (sommario):
Amomum villosum Lour. is an important Chinese medicinal plant that has diverse medicinal functions, and mainly contains volatile terpenes. This study aims to explore the WRKY transcription factors (TFs) and terpene synthase (TPS) unigenes that might be involved in terpene biosynthesis in A. villosum, and thus providing some new information on the regulation of terpenes in plants. RNA sequencing of A. villosum induced by methyl jasmonate (MeJA) revealed that the WRKY family was the second largest TF family in the transcriptome. Thirty-six complete WRKY domain sequences were expressed in response to MeJA. Further, six WRKY unigenes were highly correlated with eight deduced TPS unigenes. Ultimately, we combined the terpene abundance with the expression of candidate WRKY TFs and TPS unigenes to presume a possible model wherein AvWRKY61, AvWRKY28, and AvWRKY40 might coordinately trans-activate the AvNeoD promoter. We propose an approach to further investigate TF unigenes that might be involved in terpenoid biosynthesis, and identified four unigenes for further analyses.
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Elzinga, Sytze, Jorge Dominguez-Alonzo, Raquel Keledjian, Brad Douglass e Jeffrey C. Raber. "Acetone as Artifact of Analysis in Terpene Samples by HS-GC/MS". Molecules 27, n. 18 (16 settembre 2022): 6037. http://dx.doi.org/10.3390/molecules27186037.
Testo completoAbstract (sommario):
Cannabis-infused product manufacturers often add terpenes to enhance flavor. Meanwhile, labeling requirements for these same products necessitate testing for residual solvent levels. We have found that heating terpene samples containing an oxygen or air atmosphere results in the detection of significantly higher levels of acetone when compared to the same compound in argon atmosphere using temperature regimes common to headspace autosampler routines. This formation was statistically significant (p = 0.05) for most of the predominant terpenes found in cannabis. The largest increase in acetone formation was seen for terpinolene which showed an 885% increase in oxygen atmosphere (4603.6 PPM) when compared to analysis under argon (519.9 PPM). Cannabinoids were shown to reduce this formation and explain why high levels of acetone are not reported in cannabis extracts, even though these can contain up to 40% terpenes.
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Dickschat, Jeroen S. "Terpenes". Beilstein Journal of Organic Chemistry 15 (13 dicembre 2019): 2966–67. http://dx.doi.org/10.3762/bjoc.15.292.
Testo completo