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https://www.readbyqxmd.com/read/28937642/essential-oils-as-an-alternative-to-pyrethroids-resistance-against-anopheles-species-complex-giles-diptera-culicidae
#1
REVIEW
Olivier Gnankiné, Imaël Henri Nestor Bassolé
Widespread resistance of Anopheles sp. populations to pyrethroid insecticides has led to the search for sustainable alternatives in the plant kingdom. Among many botanicals, there is great interest in essential oils and their constituents. Many researchers have explored essential oils (EOs) to determine their toxicity and identify repellent molecules that are effective against Anopheles populations. Essential oils are volatile and fragrant substances with an oily consistency typically produced by plants. They contain a variety of volatile molecules such as terpenes and terpenoids, phenol-derived aromatic components and aliphatic components at quite different concentrations with a significant insecticide potential, essentially as ovicidal, larvicidal, adulticidal, repellency, antifeedant, growth and reproduction inhibitors...
September 22, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28935253/effects-of-nerolidol-and-limonene-on-stratum-corneum-membranes-a-probe-epr-and-fluorescence-spectroscopy-study
#2
Sebastião Antonio Mendanha, Cássia Alessandra Marquezin, Amando Siuiti Ito, Antonio Alonso
The sesquiterpene nerolidol and the monoterpene limonene are potent skin-permeation enhancers that have also been shown to have antitumor, antibacterial, antifungal and antiparasitic activities. Because terpenes are membrane-active compounds, we used electron paramagnetic resonance (EPR) spectroscopy of three membrane spin labels combined with the fluorescence spectroscopy of three lipid probes to study the interactions of these terpenes with stratum corneum (SC) intercellular membranes. An experimental apparatus was developed to assess the lipid fluidity of hydrated SC membranes via the fluorescence anisotropy of extrinsic membrane probes...
September 18, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/28934377/the-environmental-acinetobacter-baumannii-isolate-dsm30011-reveals-clues-into-the-preantibiotic-era-genome-diversity-virulence-potential-and-niche-range-of-a-predominant-nosocomial-pathogen
#3
Guillermo D Repizo, Alejandro M Viale, Vítor Borges, María M Cameranesi, Najwa Taib, Martín Espariz, Céline Brochier-Armanet, João Paulo Gomes, Suzana P Salcedo
Acinetobacter baumannii represents nowadays an important nosocomial opportunistic pathogen whose reservoirs outside the clinical setting are obscure. Here, we traced the origins of the collection strain A. baumannii DSM30011 to an isolate first reported in 1944, obtained from the enriched microbiota responsible of the aerobic decomposition of the resinous desert shrub guayule. Whole-genome sequencing and phylogenetic analysis based on core genes confirmed DSM30011 affiliation to A. baumannii. Comparative studies with 32 complete A...
September 1, 2017: Genome Biology and Evolution
https://www.readbyqxmd.com/read/28933107/-research-progress-of-chemical-constituents-and-pharmacological-activities-of-essential-oil-of-ligusticum-chuanxiong
#4
REVIEW
Jing-Chang Du, Xiao-Fang Xie, Liang Xiong, Chen Sun, Cheng Peng
Essential oil is the low polar and volatile components distilled or extracted from Ligusticum chuanxiong, the dry root of perennial herb L. chuanxiong, which has proven to be one of the main biological active ingredients of L. chuanxiong. Studies suggested that essential oil of L. chuanxiong mainly contains phthalide, terpene alcohols and fatty acids compounds. Different regions or varied extraction technology had influences on the type and contents of compound in essential oil of L. chuanxiong and the total yield efficiency of essential oil, while the differences among the distribution of compounds leads to the variant pharmacological function of essential oil of L...
December 2016: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/28933084/-cloning-and-bioinformatics-analysis-of-1-hydroxy-2-methyl-2-e-butenyl-4-diphosphate-reductase%C3%AF-pchdr1%C3%AF-gene-in-phlegmarirus-carinatus
#5
Zhi-Li Zhang, Hai-Zhou Lv, Xu Guo, Liu He, Jing-Yuan Song, Chao Sun, Hong-Mei Luo
The open reading frame of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (HDR) was cloned from Phlegmarirus carinatus by RT-PCR method and the sequence was analyzed by bioinformatics tools. After searching the transcriptome dataset of P. carinatus, one unique sequence encoding 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase was discovered. The primers were designed according to the cDNA sequence of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase from the dataset. And then, the open reading frame (ORF) of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase, named as PcHDR1 (GenBank Accession number:JQ957845), was cloned by RT-PCR strategy with the template of mixed RNA extracted from roots, stem and leaf of P...
November 2016: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/28932891/identification-of-terpenes-and-essential-oils-by-means-of-static-headspace-gas-chromatography-ion-mobility-spectrometry
#6
Roman Rodríguez-Maecker, Eduardo Vyhmeister, Stefan Meisen, Antonio Rosales Martinez, Andriy Kuklya, Ursula Telgheder
Static headspace gas chromatography-ion mobility spectrometry (SHS GC-IMS) is a relatively new analytical technique that has considerable potential for analysis of volatile organic compounds (VOCs). In this study, SHS GC-IMS was used for the identification of the major terpene components of various essential oils (EOs). Based on the data obtained from 25 terpene standards and 50 EOs, a database for fingerprint identification of characteristic terpenes and EOs was generated utilizing SHS GC-IMS for authenticity testing of fragrances in foods, cosmetics, and personal care products...
September 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28931629/selinene-volatiles-are-essential-precursors-for-maize-defense-promoting-fungal-pathogen-resistance
#7
Yezhang Ding, Alisa Huffaker, Tobias G Köllner, Philipp Weckwerth, Christelle A M Robert, Joseph L Spencer, Alexander E Lipka, Eric A Schmelz
To ensure food security, maize (Zea mays) is a model crop for understanding useful traits underlying stress resistance. In contrast to foliar biochemicals, root defenses limiting the spread of disease remain poorly described. To better understand below-ground defenses in the field, we performed root metabolomic profiling and uncovered unexpectedly high levels of the sesquiterpene volatile β-selinene and the corresponding non-volatile antibiotic derivative, β-costic acid. The application of metabolite-based quantitative trait loci (mQTL) mapping using bi-parental populations, genome wide association studies, and near-isogenic lines (NILs) enabled the identification of terpene synthase 21 (ZmTps21) on chromosome 9 as a β-costic acid pathway candidate gene...
September 20, 2017: Plant Physiology
https://www.readbyqxmd.com/read/28928524/volatiles-formation-in-gelled-emulsions-enriched-in-polyunsaturated-fatty-acids-during-storage-type-of-oil-and-antioxidant
#8
Lucía Gayoso, Candelaria Poyato, María Isabel Calvo, Rita Yolanda Cavero, Diana Ansorena, Iciar Astiasarán
Gelled emulsions with carrageenan are a novel type of emulsion that could be used as a carrier of unsaturated fatty acids in functional foods formulations. Lipid degradation through volatile compounds was studied in gelled emulsions which were high in polyunsaturated oils (sunflower or algae oil) after 49 days of storage. Aqueous Lavandula latifolia extract was tested as a natural antioxidant. Analysis of the complete volatile profile of the samples resulted in a total of 40 compounds, classified in alkanes, alkenes, aldehydes, ketones, acids, alcohols, furans, terpenes and aromatic hydrocarbons...
August 2017: Journal of Food Science and Technology
https://www.readbyqxmd.com/read/28926863/evaluation-of-cannabinoid-and-terpenoid-content-cannabis-flower-compared-to-supercritical-co2-concentrate
#9
Michelle Sexton, Kyle Shelton, Pam Haley, Mike West
A recent cannabis use survey revealed that 60% of cannabis users rely on smelling the flower to select their cannabis. Olfactory indicators in plants include volatile compounds, principally represented by the terpenoid fraction. Currently, medicinal- and adult-use cannabis is marketed in the United States with relatively little differentiation between products other than by a common name, association with a species type, and Δ-9 tetrahydrocannabinol/cannabidiol potency. Because of this practice, how terpenoid compositions may change during an extraction process is widely overlooked...
September 19, 2017: Planta Medica
https://www.readbyqxmd.com/read/28926261/late-stage-terpene-cyclization-by-an-integral-membrane-cyclase-in-the-biosynthesis-of-isoprenoid-epoxycyclohexenone-natural-products
#10
Man-Cheng Tang, Xiaoqing Cui, Xueqian He, Zhuang Ding, Tianjiao Zhu, Yi Tang, Dehai Li
Macrophorins are representative examples of isoprenoid epoxycyclohexenones containing cyclized drimane moieties. We located and characterized the biosynthetic gene cluster of macrophorin from Penicillium terrestris. MacJ encoded by this cluster was characterized to be the first example of a membrane-bound type-II terpene cyclase catalyzing the cyclization of meroterpenoids via direct protonation of the terminal olefinic bond in acyclic yanuthones. The late-stage functionalization and substrate promiscuity of MacJ make it a potential biocatalyst for the synthesis of macrophorin analogues...
September 19, 2017: Organic Letters
https://www.readbyqxmd.com/read/28926242/structure-function-studies-of-artemisia-tridentata-farnesyl-diphosphate-synthase-and-chrysanthemyl-diphosphate-synthase-by-site-directed-mutagenesis-and-morphogenesis
#11
J Scott Lee, Jian-Jung Pan, Gurusankar Ramamoorthy, C Dale Poulter
The amino acid sequences of farnesyl diphosphate synthase (FPPase) and chrysanthemyl diphosphate synthase (CPPase) from Artemisia tridentata ssp. Spiciformis, minus their chloroplast targeting regions, are 71% identical and 90% similar. FPPase efficiently and selectively synthesizes the "regular" sesquiterpenoid farnesyl diphosphate (FPP) by coupling isopentenyl diphosphate (IPP) to dimethylallyl diphosphate (DMAPP) and then to geranyl diphosphate (GPP). In contrast, CPPase is an inefficient promiscuous enzyme, which synthesizes the "irregular" monoterpenes chrysanthemyl diphosphate (CPP), lavandulyl diphosphate (LPP), and trace quantities of maconelliyl diphosphate (MPP) from two molecules of DMAPP, in addition to coupling IPP to DMAPP...
September 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28922556/structure-and-mechanism-of-the-monoterpene-cyclolavandulyl-diphosphate-synthase-that-catalyses-consecutive-condensation-and-cyclisation
#12
Tomohisa Kuzuyama, Takeo Tomita, Masaya Kobayashi, Yuma Karita, Yoko Yasuno, Tetsuro Shinada, Makoto Nishiyama
Here, we report the three-dimensional structure of cyclolavandulyl diphosphate (CLPP) synthase (CLDS), which consecutively catalyses the condensation of two molecules of dimethylallyl diphosphate (DMAPP) followed by cyclisation to form a cyclic monoterpene, CLPP. The structures of apo-CLDS and CLDS in complex with Tris, pyrophosphate, and Mg2+ ion were refined at 2.00 Å resolution and 1.73 Å resolution, respectively. CLDS adopts a typical fold for cis-prenyl synthases and forms a homo-dimeric structure. An in vitro reaction using a regiospecifically 2H-substituted DMAPP substrate revealed the intramolecular proton transfer mechanism of the CLDS reaction...
September 18, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28921887/chemical-components-biological-activities-and-toxicological-evaluation-of-the-fruit-aril-of-two-precious-plant-species-from-genus-taxus
#13
Na Li, Zheng Pan, Dan Zhang, Huaxing Wang, Bao Yu, Shengping Zhao, Jiajia Guo, Jianwei Wang, Ling Yao, Weiguo Cao
The fruit (aril) of the endangered genus Taxus plants is an abandoned herbal resource. Traditionally, people enthusiasticly focus on its bark, its renewable, tremendous arils fall into the soil with seeds after they are mature. The present research investigated the fruit of two species from the genus Taxus, Taxus chinensis var. mairei and Taxus media, with regards to their antioxidant and antihyperglycaemic activities, safety, and bioactive constituents. Results showed that T. chinensis var. mairei and T. media both had certain biological activities with T...
September 18, 2017: Chemistry & Biodiversity
https://www.readbyqxmd.com/read/28906071/construction-of-quaternary-stereogenic-centers-in-the-total-synthesis-of-natural-products
#14
Evgeny V Prusov
Total syntheses of the tetracyclic terpene waihoensene and the densely functionalized tetracyclic compound ryanodol have recently been reported. Both approaches constitute examples of the efficient and innovative construction of multiple quaternary centers.
September 14, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28905380/enhancing-blood-donor-skin-disinfection-using-natural-oils
#15
Meshari Alabdullatif, Imen Boujezza, Mohamed Mekni, Mariam Taha, Dilini Kumaran, Qi-Long Yi, Ahmed Landoulsi, Sandra Ramirez-Arcos
BACKGROUND: Effective donor skin disinfection is essential in preventing bacterial contamination of blood components with skin flora bacteria like Staphylococcus epidermidis. Cell aggregates of S. epidermidis (biofilms) are found on the skin and are resistant to the commonly used donor skin disinfectants chlorhexidine-gluconate and isopropyl alcohol. It has been demonstrated that essential oils synergistically enhance the antibacterial activity of chlorhexidine-gluconate. The objective of this study was to test plant-extracted essential oils in combination with chlorhexidine-gluconate or chlorhexidine-gluconate plus isopropyl alcohol for their ability to eliminate S...
September 14, 2017: Transfusion
https://www.readbyqxmd.com/read/28905185/hepatotoxicity-of-monoterpenes-and-sesquiterpenes
#16
REVIEW
Tomáš Zárybnický, Iva Boušová, Martin Ambrož, Lenka Skálová
Public interest in natural therapies has increased significantly over past decades. Herbs and herbal products are extensively consumed worldwide and they are generally considered as safe. However, this may not always be true as many cases of herb-induced liver injury are reported every year. The liver is a frequent target tissue of toxicity from all classes of toxicants as liver structure and function predispose it to high sensitivity to xenobiotics. The present review is focused on the hepatotoxic properties of monoterpenes and sesquiterpenes, plant secondary metabolites that represent the major components of essential oils wildly used in folk medicines, pharmaceutical industry and cosmetics...
September 13, 2017: Archives of Toxicology
https://www.readbyqxmd.com/read/28904624/pd-oac-2-ph3p-catalyzed-dimerization-of-isoprene-and-synthesis-of-monoterpenic-heterocycles
#17
Dominik Kellner, Maximilian Weger, Andrea Gini, Olga García Mancheño
The palladium-catalyzed dimerization of isoprene is a practical approach of synthesizing monoterpenes. Though several highly selective methods have been reported, most of them still required pressure or costly ligands for attaining the active system and desired selectivity. Herein, we present a simple and economical procedure towards the tail-to-tail dimer using readily available Pd(OAc)2 and inexpensive triphenylphosphine as ligand. Furthermore, simple screw cap vials are employed, allowing carrying out the reaction at low pressure...
2017: Beilstein Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28904620/18-hydroxydolabella-3-7-diene-synthase-a-diterpene-synthase-from-chitinophaga-pinensis
#18
Jeroen S Dickschat, Jan Rinkel, Patrick Rabe, Arman Beyraghdar Kashkooli, Harro J Bouwmeester
The product obtained in vitro from a diterpene synthase encoded in the genome of the bacterium Chitinophaga pinensis, an enzyme previously reported to have germacrene A synthase activity during heterologous expression in Escherichia coli, was identified by extensive NMR-spectroscopic methods as 18-hydroxydolabella-3,7-diene. The absolute configuration of this diterpene alcohol and the stereochemical course of the terpene synthase reaction were addressed by isotopic labelling experiments. Heterologous expression of the diterpene synthase in Nicotiana benthamiana resulted in the production of 18-hydroxydolabella-3,7-diene also in planta, while the results from the heterologous expression in E...
2017: Beilstein Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28904610/correction-dynamic-behavior-of-rearranging-carbocations-implications-for-terpene-biosynthesis
#19
Stephanie R Hare, Dean J Tantillo
[This corrects the article DOI: 10.3762/bjoc.12.41.].
2017: Beilstein Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28901763/bioassay-guided-isolation-of-antibacterial-metabolites-from-emericella-sp-tj29
#20
Yan He, Zhengxi Hu, Qin Li, Jinfeng Huang, Xiao-Nian Li, Hucheng Zhu, Junjun Liu, Jianping Wang, Yongbo Xue, Yonghui Zhang
Bioassay-guided isolation of metabolites from cultures of the plant-derived fungus Emericella sp. TJ29 yielded three new terpene-polyketide hybrid meroterpenoids, emervaridones A-C (1-3), two new polyketides, varioxiranediols A and B (5 and 6), and three known analogues (4, 7, and 8). The structures and absolute configurations of these new compounds were elucidated by spectroscopic analyses, single-crystal X-ray diffraction, Mo2(OAc)4-induced electronic circular dichroism (ECD) data, and ECD calculations. To date, only one compound (4) bearing the emervaridone-type carbocyclic skeleton has been reported...
September 13, 2017: Journal of Natural Products
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