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Terpenes

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https://www.readbyqxmd.com/read/28651364/temporal-effects-of-prescribed-burning-on-terpene-production-in-mediterranean-pines
#1
Teresa Valor, Elena Ormeño, Pere Casals
Prescribed burning is used to reduce fuel hazard but underburning can damage standing trees. The effect of burning on needle terpene storage, a proxy for secondary metabolism, in fire-damaged pines is poorly understood despite the protection terpenes confer against biotic and abiotic stressors. We investigated variation in needle terpene storage after burning in three Mediterranean pine species featuring different adaptations to fire regimes. In two pure-stands of Pinus halepensis Mill. and two mixed-stands of Pinus sylvestris L...
June 23, 2017: Tree Physiology
https://www.readbyqxmd.com/read/28650352/the-effect-of-aging-and-priming-on-same-different-judgments-between-text-and-partially-masked-speech
#2
Richard L Freyman, Jenna Terpening, Angela C Costanzi, Karen S Helfer
OBJECTIVES: It is well known from previous research that when listeners are told what they are about to hear before a degraded or partially masked auditory signal is presented, the speech signal "pops out" of the background and becomes considerably more intelligible. The goal of this research was to explore whether this priming effect is as strong in older adults as in younger adults. DESIGN: Fifty-six adults-28 older and 28 younger-listened to "nonsense" sentences spoken by a female talker in the presence of a 2-talker speech masker (also female) or a fluctuating speech-like noise masker at 5 signal-to-noise ratios...
June 22, 2017: Ear and Hearing
https://www.readbyqxmd.com/read/28643772/cryptic-indole-hydroxylation-by-a-non-canonical-terpenoid-cyclase-parallels-bacterial-xenobiotic-detoxification
#3
Susann Kugel, Martin Baunach, Philipp Baer, Mie Ishida-Ito, Srividhya Sundaram, Zhongli Xu, Michael Groll, Christian Hertweck
Terpenoid natural products comprise a wide range of molecular architectures that typically result from C-C bond formations catalysed by classical type I/II terpene cyclases. However, the molecular diversity of biologically active terpenoids is substantially increased by fully unrelated, non-canonical terpenoid cyclases. Their evolutionary origin has remained enigmatic. Here we report the in vitro reconstitution of an unusual flavin-dependent bacterial indoloterpenoid cyclase, XiaF, together with a designated flavoenzyme-reductase (XiaP) that mediates a key step in xiamycin biosynthesis...
June 15, 2017: Nature Communications
https://www.readbyqxmd.com/read/28641448/negative-inotropism-of-terpenes-on-guinea-pig-left-atrium-structure-activity-relationships
#4
Carla M L Vasconcelos, Ingrid S N Oliveira, José N A Santos, Américo A Souza, José E R Menezes-Filho, Júlio A Silva Neto, Tamires C Lima, Damião P de Sousa
The aim of this work was to evaluate the pharmacological effect of seven structurally related terpenes on the contractility of cardiac muscle. The effect of terpenes was studied on isolated electrically driven guinea pig left atrium. From concentration-response curves for inotropic effect were determined the EC50 and relative potency of such terpenes. Our results revealed that all terpenes, except phytol, showed ability to reduce the contractile response of guinea pig left atrium. Further, relative potency was directly related to the number of isoprene units and to the lipophilicity of the compounds...
June 23, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28637270/in-planta-recapitulation-of-isoprene-synthases-evolution-from-ocimene-synthases
#5
Mingai Li, Jia Xu, Alberto Algarra Alarcon, Silvia Carlin, Enrico Barbaro, Luca Cappellin, Violeta Velikova, Urska Vrhovsek, Francesco Loreto, Claudio Varotto
Isoprene is the most abundant biogenic volatile hydrocarbon compound naturally emitted by plants and plays a major role in atmospheric chemistry. It has been proposed that isoprene synthases (IspS) may readily evolve from other terpene synthases, but this hypothesis has not been experimentally investigated.We isolated and functionally validated in Arabidopsis the first isoprene synthase gene, AdoIspS, from a monocotyledonous species (Arundo donax L., Poaceae). Phylogenetic reconstruction indicates that AdoIspS and dicots isoprene synthases most likely originated by parallel evolution from TPS-b monoterpene synthases...
June 16, 2017: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/28631070/lipids-of-the-tail-gland-body-and-muzzle-fur-of-the-red-fox-vulpes-vulpes
#6
Stuart McLean, Noel W Davies, David S Nichols
The tail gland of the red fox (Vulpes vulpes) secretes lipids containing volatile terpenes used in social communication. We have analysed lipids extracted from fur of the tail gland, body (flanks) and muzzle of foxes. GC-MS showed a novel group of iso-valerate and tiglate monoesters of alkane-1,2-diols (C18:0-22:0). There was also a larger group of Type II diesters in which a second, longer chain, fatty acid (FA) was attached to the free alcohol group. LC-MS showed the full range of diol diesters, mostly C36:0-50:0, with smaller amounts of the corresponding mono-unsaturated tiglate esters...
June 19, 2017: Lipids
https://www.readbyqxmd.com/read/28630399/dietary-mastic-oil-extracted-from-pistacia-lentiscus-var-chia-suppresses-tumor-growth-in-experimental-colon-cancer-models
#7
Katerina Spyridopoulou, Angeliki Tiptiri-Kourpeti, Evangeli Lampri, Eleni Fitsiou, Stavros Vasileiadis, Manolis Vamvakias, Haido Bardouki, Anna Goussia, Vasiliki Malamou-Mitsi, Mihalis I Panayiotidis, Alex Galanis, Aglaia Pappa, Katerina Chlichlia
Plant-derived bioactive compounds attract considerable interest as potential chemopreventive anticancer agents. We analyzed the volatile dietary phytochemicals (terpenes) present in mastic oil extracted from the resin of Pistacia lentiscus var. chia and comparatively investigated their effects on colon carcinoma proliferation, a) in vitro against colon cancer cell lines and b) in vivo on tumor growth in mice following oral administration. Mastic oil inhibited - more effectively than its major constituents- proliferation of colon cancer cells in vitro, attenuated migration and downregulated transcriptional expression of survivin (BIRC5a)...
June 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28625782/complex-sexual-deception-in-an-orchid-is-achieved-by-co-opting-two-independent-biosynthetic-pathways-for-pollinator-attraction
#8
Haiyang Xu, Björn Bohman, Darren C J Wong, Claudia Rodriguez-Delgado, Adrian Scaffidi, Gavin R Flematti, Ryan D Phillips, Eran Pichersky, Rod Peakall
Sexually deceptive orchids lure their specific male pollinators using volatile semiochemicals that mimic female sex pheromones. To date, the semiochemicals known to be involved consist of blends of chemically and biosynthetically related compounds. In contrast, we report that (S)-β-citronellol and 2-hydroxy-6-methylacetophenone, two biosynthetically distinct compounds, are the active semiochemicals in Caladenia plicata, which is pollinated by male Zeleboria sp. thynnine wasps. They are also sex pheromone components of the female Zeleboria...
June 12, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28624283/effect-of-pasture-versus-indoor-feeding-systems-on-quality-characteristics-nutritional-composition-and-sensory-and-volatile-properties-of-full-fat-cheddar-cheese
#9
Tom F O'Callaghan, David T Mannion, Deirdre Hennessy, Stephen McAuliffe, Maurice G O'Sullivan, Natasha Leeuwendaal, Tom P Beresford, Pat Dillon, Kieran N Kilcawley, Jeremiah J Sheehan, R Paul Ross, Catherine Stanton
The purpose of this study was to investigate the effects of pasture-based versus indoor total mixed ration (TMR) feeding systems on the chemical composition, quality characteristics, and sensory properties of full fat Cheddar cheeses. Fifty-four multiparous and primiparous Friesian cows were divided into 3 groups (n = 18) for an entire lactation. Group 1 was housed indoors and fed a TMR diet of grass silage, maize silage, and concentrates; group 2 was maintained outdoors on perennial ryegrass only pasture (GRS); and group 3 was maintained outdoors on perennial ryegrass/white clover pasture (CLV)...
June 14, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/28623722/recent-advances-in-synthetic-biology-for-engineering-isoprenoid-production-in-yeast
#10
REVIEW
Claudia E Vickers, Thomas C Williams, Bingyin Peng, Joel Cherry
Isoprenoids (terpenes/terpenoids) have many useful industrial applications, but are often not produced at industrially viable level in their natural sources. Synthetic biology approaches have been used extensively to reconstruct metabolic pathways in tractable microbial hosts such as yeast and re-engineer pathways and networks to increase yields. Here we review recent advances in this field, focusing on central carbon metabolism engineering to increase precursor supply, re-directing carbon flux for production of C10, C15, or C20 isoprenoids, and chemical decoration of high value diterpenoids (C20)...
June 14, 2017: Current Opinion in Chemical Biology
https://www.readbyqxmd.com/read/28610733/comparison-of-fortified-sfursat-and-passito-wines-produced-from-fresh-and-dehydrated-grapes-of-aromatic-black-cv-moscato-nero-vitis-vinifera-l
#11
Carolina Ossola, Simone Giacosa, Fabrizio Torchio, Susana Río Segade, Alberto Caudana, Enzo Cagnasso, Vincenzo Gerbi, Luca Rolle
Moscato nero d'Acqui is an Italian aromatic black winegrape variety characterized by a low content of anthocyanins (mostly tri-substituted), a satisfactory content of high molecular mass tannins, and a fair amount of terpenes. The grapes were subjected to a postharvest dehydration process under controlled thermohygrometric conditions (16-18°C, 55-70 RH%, 0.6m/s air speed) with the aim to produce three different special wine types (fortified, sfursat, and passito) from fresh, partially dehydrated (27°Brix), and withered (36°Brix) grapes, respectively...
August 2017: Food Research International
https://www.readbyqxmd.com/read/28606152/heterologous-expression-of-cytotoxic-sesquiterpenoids-from-the-medicinal-mushroom-lignosus-rhinocerotis-in-yeast
#12
Hui-Yeng Yeannie Yap, Mariano Jordi Muria-Gonzalez, Boon-Hong Kong, Keith A Stubbs, Chon-Seng Tan, Szu-Ting Ng, Nget-Hong Tan, Peter S Solomon, Shin-Yee Fung, Yit-Heng Chooi
BACKGROUND: Genome mining facilitated by heterologous systems is an emerging approach to access the chemical diversity encoded in basidiomycete genomes. In this study, three sesquiterpene synthase genes, GME3634, GME3638, and GME9210, which were highly expressed in the sclerotium of the medicinal mushroom Lignosus rhinocerotis, were cloned and heterologously expressed in a yeast system. RESULTS: Metabolite profile analysis of the yeast culture extracts by GC-MS showed the production of several sesquiterpene alcohols (C15H26O), including cadinols and germacrene D-4-ol as major products...
June 12, 2017: Microbial Cell Factories
https://www.readbyqxmd.com/read/28603534/combining-metabolic-profiling-and-gene-expression-analysis-to-reveal-the-biosynthesis-site-and-transport-of-ginkgolides-in-ginkgo-biloba-l
#13
Xu Lu, Hua Yang, Xinguang Liu, Qian Shen, Ning Wang, Lian-Wen Qi, Ping Li
The most unique components of Ginkgo biloba extracts are terpene trilactones (TTLs) including ginkgolides and bilobalide. Study of TTLs biosynthesis has been stagnant in recent years. Metabolic profiling of 40 compounds, including TTLs, flavonoids, and phenolic acids, were globally analyzed in leaf, fibrous root, main root, old stem and young stem extracts of G. biloba. Most of the flavonoids were mainly distributed in the leaf and old stem. Most of phenolic acids were generally distributed among various tissues...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28593175/polyketide-terpene-hybrid-metabolites-from-an-endolichenic-fungus-pestalotiopsis-sp
#14
Chao Yuan, Gang Ding, Hai-Ying Wang, Yu-Hua Guo, Hai Shang, Xiao-Jun Ma, Zhong-Mei Zou
Five new polyketide-terpene hybrid metabolites (1-5) with highly functionalized groups, together with six known derivatives (6-11), were isolated from the endolichenic fungus Pestalotiopsis sp. Their structures were elucidated by extensive NMR experiments including (1)H, (13)C, HMQC, COSY, and HMBC. The relative configurations of the new compounds were determined by analysis of coupling constants and ROESY correlations. The absolute configurations especially the secondary alcohol at C-15 in 1 and secondary alcohol at C-14 in 5 were established via the CD experiments of the in situ formed [Rh2(OCOCF3)4] complex with the acetonide derivatives...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28590723/terpene-cyclizations-inside-a-supramolecular-catalyst-leaving-group-controlled-product-selectivity-and-mechanistic-studies
#15
Qi Zhang, Lorenzo Catti, Jürgen Pleiss, Konrad Tiefenbacher
The tail-to-head terpene cyclization is arguably one of the most complex reactions found in nature. The hydrogen-bond-based resorcinarene capsule represents the first man-made enzyme-like catalyst that is capable of catalyzing this reaction. Based on noncovalent interactions between the capsule and the substrate, the product selectivity can be tuned by using different leaving groups. A detailed mechanistic investigation was performed to elucidate the reaction mechanism. For the cyclization of geranyl acetate, it was found that the cleavage of the leaving group is the rate-determining step...
June 23, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28590436/volatile-organic-compounds-in-anatomical-pathology-wards-comparative-and-qualitative-assessment-of-indoor-airborne-pollution
#16
Massimo Cipolla, Alberto Izzotti, Filippo Ansaldi, Paolo Durando, Maria Teresa Piccardo
The impact of volatile organic compounds (VOCs) on indoor air quality and on human health is widely recognized. However, VOC contamination in hospital indoor air is rarely studied and chemical compounds that singularly do not show high toxicity are not submitted to any regulation. This study aimed to compare VOC contamination in two different anatomical pathology wards in the same hospital. Hydrocarbons, alcohols, and terpenes were sampled by passive diffusive samplers. Analytical tests were performed by thermal desorption coupled with gas chromatography and mass spectrometry detector...
June 7, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28583128/terpene-constituents-of-the-aerial-parts-phenolic-content-antibacterial-potential-free-radical-scavenging-and-antioxidant-activity-of-callistemon-citrinus-curtis-skeels-myrtaceae-from-eastern-cape-province-of-south-africa
#17
Rotimi A Larayetan, Omobola O Okoh, Alexander Sadimenko, Anthony I Okoh
BACKGROUND: Volatile oil from aromatic plants has been used by ancient Egyptians in embalming for the inhibition of bacterial growth and prevention of decay, Callistemon citrinus is used in traditional therapies for the treatment of bronchitis, cough, inflammation and as an antimicrobial herbs. This study examines the essential constituents of the volatile oils obtained from the aerial parts of the plant as well as its antioxidant activity, free radical scavenging, phenolic content and the antibacterial potential of the oils...
June 5, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28575806/phytol-induces-ros-mediated-apoptosis-by-induction-of-caspase-9-and-3-through-activation-of-trail-fas-and-tnf-receptors-and-inhibits-tumor-progression-factor-glucose-6-phosphate-dehydrogenase-in-lung-carcinoma-cell-line-a549
#18
Parth Thakor, Ramalingam B Subramanian, Sampark S Thakkar, Arabinda Ray, Vasudev R Thakkar
A number of drugs as well as lead molecules are isolated from natural sources. Phytol is one of such lead molecule belongs to terpenes group distributed widely in medicinal plants. In the present work, we investigated the cytotoxic behavior of phytol on human lung carcinoma cells (A549). Phytol was found to cause characteristic apoptotic morphological changes and generation of ROS in A549 cells. The mechanism of phytol involved the activation of TRAIL, FAS and TNF-α receptors along with caspase 9 and 3. In silico molecular docking studies revealed that phytol has a good binding affinity with glucose-6-phosphate dehydrogenase (G6PD), which is known to promote tumor proliferation...
August 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28572959/bioactive-phytochemicals-in-an-aqueous-extract-of-the-leaves-of-talinum-triangulare
#19
Catherine C Ikewuchi, Jude C Ikewuchi, Mercy O Ifeanacho
An aqueous leaf extract of Talinum triangulare was screened for the presence of bioactive molecules, using gas chromatography coupled with pulse and flame ionization detectors. It had high carotenoids; moderate benzoic acid derivatives, hydroxycinnamates and flavonoids; and low terpenes, alkaloids, phytosterols, allicins, glycosides, saponins, and lignans contents. Ten known carotenoids (mainly 50.42% carotene and 33.30% lycopene), nine benzoic acid derivatives (mainly 84.63% ferulic acid and 11.92% vanillic acid), and six hydroxycinnamates (55...
May 2017: Food Science & Nutrition
https://www.readbyqxmd.com/read/28560831/stereochemical-assignment-of-fusiccocadiene-from-nmr-shielding-constants-and-vibrational-circular-dichroism-spectroscopy
#20
Christian Merten, Michael Dirkmann, Frank Schulz
The absolute configuration (AC) of the common precursor of the fusicoccane family of terpenoids, fusicocca-2,10(14)-diene (FCdiene), had only been deduced by a lengthy total synthesis, or indirectly from crystal structures of fusicoccin A. However, in particular the AC determinations based on downstream products of the terpene synthase intrinsically overlook potential epimerization reactions. In this contribution, we confirm the relative stereochemistry of FCdiene by comparison of experimental and predicted (13) C-NMR chemical shifts, and finally determine the absolute configuration from an analysis of its infrared and vibrational circular dichroism spectra...
May 30, 2017: Chirality
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