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https://www.readbyqxmd.com/read/28213239/new-urea-modified-paper-substrate-for-enhanced-analytical-performance-of-negative-ion-mode-paper-spray-mass-spectrometry
#1
Jingjing Liu, Yan He, Shuo Chen, Ming Ma, Shouzuo Yao, Bo Chen
Electrospray ionization mass spectrometry (ESI-MS) analysis in the negative ion mode is adversely affected by ionization suppression caused by electrical discharge and the presence of salts. Paper spray mass spectrometry (PS-MS) also suffers from the above phenomenon, being built on principles similar to those of ESI. Herein, we report the use of a paper substrate modified by 1-[3-(trimethoxysilyl)propyl]urea to improve the sensitivity of quantitative PS-MS analysis in the negative ion mode. The obtained results demonstrated that the urea modified paper substrate can effectively bind anions and highly polar compounds in the sample solution, decreasing competitive ionization in the negative ion mode of PS-MS and significantly reducing the signal intensity of Cl(-) adducts...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28211171/applications-of-the-wittig-still-rearrangement-in-organic-synthesis
#2
Lukas Rycek, Tomas Hudlicky
This review traces the discovery of the Wittig-Still rearrangement and its applications in organic synthesis. Its relationship to Wittig rearrangements is discussed along with detailed analysis of E/Z- and diastereoselectivity. Modifications of the products arising from the Wittig-Still rearrangement are reviewed in the context of increased complexity in intermediates potentially useful in target oriented synthesis. Early applications of the Wittig-Still rearrangement to modifications of steroids are reviewed as are applications to various terpene and alkaloid natural product targets and miscellaneous compounds...
February 16, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28210947/nano-formulation-enhances-insecticidal-activity-of-natural-pyrethrins-against-aphis-gossypii-hemiptera-aphididae-and-retains-their-harmless-effect-to-non-target-predators
#3
Nikos E Papanikolaou, Argyro Kalaitzaki, Filitsa Karamaouna, Antonios Michaelakis, Vassiliki Papadimitriou, Vassilis Dourtoglou, Dimitrios P Papachristos
The insecticidal activity of a new nano-formulated natural pyrethrin was examined on the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), and the predators Coccinella septempunctata L. (Coleoptera: Coccinellidae) and Macrolophus pygmaeus Rambur (Hemiptera: Miridae), in respect with the nano-scale potential to create more effective and environmentally responsible pesticides. Pyrethrin was nano-formulated in two water-in-oil micro-emulsions based on safe biocompatible materials, i.e., lemon oil terpenes as dispersant, polysorbates as stabilizers, and mixtures of water with glycerol as the dispersed aqueous phase...
February 16, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28210904/acute-and-neuropathic-orofacial-antinociceptive-effect-of-eucalyptol
#4
José de Maria de Albuquerque de Melo Júnior, Marina de Barros Mamede Vidal Damasceno, Sacha Aubrey Alves Rodrigues Santos, Talita Matias Barbosa, João Ronielly Campêlo Araújo, Antonio Eufrásio Vieira-Neto, Deysi Viviana Tenazoa Wong, Roberto César Pereira Lima-Júnior, Adriana Rolim Campos
Terpenes have a wide range of pharmacological properties, including antinociceptive action. The anti-inflammatory and antinociceptive effects of eucalyptol are well established. The purpose of this study was to evaluate the antinociceptive effect of eucalyptol on acute and neuropathic orofacial pain in rodent models. Acute orofacial and corneal nociception was induced with formalin, capsaicin, glutamate and hypertonic saline in mice. In another series, animals were pretreated with capsazepine or ruthenium red to evaluate the involvement of TRPV1 receptors in the effect of eucalyptol...
February 16, 2017: Inflammopharmacology
https://www.readbyqxmd.com/read/28209457/metabolomic-approach-reveals-the-biochemical-mechanisms-underlying-drought-stress-tolerance-in-thyme
#5
Parviz Moradi, Brian Ford-Lloyd, Jeremy Pritchard
Thyme as a perennial herb has been recognized globally for its antimicrobial, antiseptic and spasmolytic effects. In this investigation, we have used non-targeted metabolite and volatile profiling combined with the morpho-physiological parameters in order to understand the responses at the metabolite and physiological level in drought sensitive and tolerant thyme plant populations. The results at the metabolic level identified the significantly affected metabolites. Significant metabolites belonging to different chemical classes consisting amino acids, carbohydrates, organic acids and lipids have been compared in tolerant and sensitive plants...
February 13, 2017: Analytical Biochemistry
https://www.readbyqxmd.com/read/28208286/derivatization-technique-to-identify-specifically-carbonyl-groups-by-infrared-spectroscopy-characterization-of-photooxidative-aging-products-in-terpenes-and-terpeneous-resins
#6
Stefan Zumbühl, Andreas Brändle, Andreas Hochuli, Nadim C Scherrer, Walter Caseri
Analysis of bioorganic materials by infrared spectroscopy (FT-IR) is frequently limited due to overlapping of diagnostic bands from the various components, which poses a fundamental problem to this analytical technique. The distinction of oxidized di- and triterpenes, for example, is hindered by the superposition of similar absorption bands of carbonyl functional groups summing up to a broad, nondistinctive signal. This study presents a technique for selective fluorination of various carboxylic acids by exposure to gaseous sulfur tetrafluoride...
February 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28207974/aamyb1-and-its-orthologue-atmyb61-affect-terpene-metabolism-and-trichome-development-in-artemisia-annua-and-arabidopsis-thaliana
#7
Luis Matías-Hernández, Weimin Jiang, Ke Yang, Kexuan Tang, Peter E Brodelius, Soraya Pelaz
The effective anti-malarial drug artemisinin (AN) isolated from Artemisia annua is relatively expensive due to the low content in the plant as it is only synthesized within the glandular trichomes. Therefore, genetic engineering of A. annua is one of the most promising approaches to improve AN yield. In this work, AaMYB1 transcription factor has been identified and characterized. When AaMYB1 is overexpressed in A. annua, either exclusively in trichomes or in the whole plant, essential AN biosynthetic genes are also overexpressed and consequently AN amount significantly increased...
February 16, 2017: Plant Journal: for Cell and Molecular Biology
https://www.readbyqxmd.com/read/28198097/inibitory-effects-of-linalool-on-fungal-pathogenicity-of-clinical-isolates-of-microsporum-canis-and-microsporum-gypseum
#8
Kaltz V S Silva, Maria I O Lima, Gustavo N Cardoso, Aldeir S Santos, Gezaíldo S Silva, Fillipe O Pereira
In humans worldwide, Microsporum sp. is a frequent agent of dermatophytsosis. When considering the emergence of resistant fungi and the clinical relevance of dermatophytosis, terpene antifungal activity is of great interest. Linalool is a monoterpene alcohol with pharmacological properties. In this study, antifungal in vitro activity of linalool and ketoconazole (as a positive control) were evaluated against clinical isolates of M. canis and M. gypseum. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of each drug were determined by broth microdilution...
February 15, 2017: Mycoses
https://www.readbyqxmd.com/read/28196976/biosynthetic-studies-on-terpenoids-produced-by-streptomyces
#9
REVIEW
Tomohisa Kuzuyama
Terpenoids are a large and highly diverse group of natural products. All terpenoids are biosynthesized from isoprenyl diphosphate formed by the consecutive condensation of the five-carbon monomer isopentenyl diphosphate (IPP) to its isomer dimethylallyl diphosphate (DMAPP). Two distinct biosynthetic pathways produce the essential primary metabolites IPP and DMAPP: the 2-C-methylerythritol 4-phosphate pathway and the mevalonate pathway. The isoprenyl substrates can be cyclized by terpene cyclase into single-ring or multi-ring products, which can be further diversified by subsequent modification reactions, such as hydroxylation and glycosylation...
February 15, 2017: Journal of Antibiotics
https://www.readbyqxmd.com/read/28196124/isoprenoid-phospholipid-conjugates-as-potential-therapeutic-agents-synthesis-characterization-and-antiproliferative-studies
#10
Anna Gliszczyńska, Natalia Niezgoda, Witold Gładkowski, Marta Świtalska, Joanna Wietrzyk
The aim of this research was to extend application field of isoprenoid compounds by their introduction into phospholipid structure as the transport vehicle. The series of novel isoprenoid phospholipids were synthesized in high yields (24-97%), their structures were fully characterized and its anticancer activity was investigated in vitro towards several cell lines of different origin. Most of synthesized compounds showed a significantly higher antiproliferative effect on tested cell lines than free terpene acids...
2017: PloS One
https://www.readbyqxmd.com/read/28195730/alternate-cyclization-cascade-initiated-by-substrate-isomer-in-multiproduct-terpene-synthase-from-medicago-truncatula
#11
Abith Vattekkatte, Stefan Garms, Wilhelm Boland
Promiscuity of terpene synthases results in the enormous diversity of terpenes found in nature. Multiproduct sesquiterpene synthase MtTPS5 isolated from Medicago truncatula generates 27 optically pure products from its natural substrate (2E,6E)-farnesyl diphosphate (FDP). In order to study the promiscuity of MtTPS5, (2Z,6E)-FDP an analogue of presumptive reaction intermediates from natural reaction cascade was utilized as a substrate. This stereoisomer induced a novel cyclization pathway leading to sesquiterpenes based on humulane, amorphene and himachalane skeletons...
February 14, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28194218/brazilian-amazon-traditional-medicine-and-the-treatment-of-difficult-to-heal-leishmaniasis-wounds-with-copaifera
#12
REVIEW
Kelly Cristina Oliveira de Albuquerque, Andreza do Socorro Silva da Veiga, João Victor da Silva E Silva, Heliton Patrick Cordovil Brigido, Erica Patrícia Dos Reis Ferreira, Erica Vanessa Souza Costa, Andrey Moacir do Rosário Marinho, Sandro Percário, Maria Fâni Dolabela
The present study describes the use of the traditional species Copaifera for treating wounds, such as ulcers scarring and antileishmanial wounds. It also relates phytochemical studies, evaluation of the leishmanicidal activity, and toxicity. The species of Copaifera with a higher incidence in the Amazon region are Copaifera officinalis, Copaifera reticulata, Copaifera multijuga Hayne. The copaiba oil is used in the Amazon's traditional medicine, especially as anti-inflammatory ingredient, in ulcers healing, and in scarring and for leishmaniasis...
2017: Evidence-based Complementary and Alternative Medicine: ECAM
https://www.readbyqxmd.com/read/28190801/acaricidal-potentials-of-the-terpene-rich-essential-oils-of-two-iranian-eucalyptus-species-against-tetranychus-urticae-koch
#13
Asgar Ebadollahi, Jalal Jalali Sendi, Mostafa Maroufpoor, Mehdi Rahimi-Nasrabadi
There is a rapid growth in the screening of plant materials for finding new bio-pesticides. In the present study, the essential oils of E. oleosa and E. torquata leaves were extracted using a Clevenger apparatus and their chemical profiles were investigated by Gas Chromatography-Mass Spectrometry (GC-MS). Among identified compounds, the terpenes had highest amount for both essential oils; 93.59% for E. oleosa and 97.69% for E. torquata. 1,8-Cineole (31.96%), α-pinene (15.25%) and trans-anethole (7.32%) in the essential oil of E...
February 10, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/28190677/bornyl-diphosphate-synthase-from-lavandula-angustifolia-a-major-monoterpene-synthase-involved-in-essential-oil-quality
#14
Yolande Despinasse, Sébastien Fiorucci, Serge Antonczak, Sandrine Moja, Aurélie Bony, Florence Nicolè, Sylvie Baudino, Jean-Louis Magnard, Frédéric Jullien
Lavender essential oils (EOs) of higher quality are produced by a few Lavandula angustifolia cultivars and mainly used in the perfume industry. Undesirable compounds such as camphor and borneol are also synthesized by lavender leading to a depreciated EO. Here, we report the cloning of bornyl diphosphate synthase of lavender (LaBPPS), an enzyme that catalyzes the production of bornyl diphosphate (BPP) and then by-products such as borneol or camphor, from an EST library. Compared to the BPPS of Salvia officinalis, the functional characterization of LaBPPS showed several differences in amino acid sequence, and the distribution of catalyzed products...
February 9, 2017: Phytochemistry
https://www.readbyqxmd.com/read/28188954/comparative-glandular-trichome-transcriptome-based-gene-characterization-reveals-reasons-for-differential-menthol-biosynthesis-in-mentha-species
#15
Md Qussen Akhtar, Nida Qamar, Pallavi Yadav, Pallavi Kulkarni, Ajay Kumar, Ajit Kumar Shasany
The genes involved in menthol biosynthesis are reported earlier in Mentha × piperita. But the information on these genes is not available in Mentha arvensis. To bridge the gap in knowledge on differential biosynthesis of monoterpenes leading to compositional variation in the essential oil of these species, a comparative transcriptome analysis of the glandular trichome was carried out. In addition to the MVA and MEP pathway genes, about 210 and 196 different terpene synthases (TPS) transcripts were identified from annotation in M...
February 11, 2017: Physiologia Plantarum
https://www.readbyqxmd.com/read/28167035/enzymatic-production-and-emission-of-floral-scent-volatiles-in-jasminum-sambac
#16
Paramita Bera, Chiranjit Mukherjee, Adinpunya Mitra
Floral scent composed of low molecular weight volatile organic compounds. The sweet fragrance of any evening blooming flower is dominated by benzenoid and terpenoid volatile compounds. Floral scent of Jasminum sambac (Oleaceae) includes three major benzenoid esters - benzylacetate, methylbenzoate, and methylsalicylate and three major terpene compounds viz. (E)-β-ocimene, linalool and α-farnesene. We analyzed concentrations and emission rates of benzenoids and terpenoids during the developmental stages of J...
March 2017: Plant Science: An International Journal of Experimental Plant Biology
https://www.readbyqxmd.com/read/28165659/needle-terpenes-as-chemotaxonomic-markers-in-pinus-subsections-pinus-and-pinaster
#17
Zorica S Mitić, Snežana Č Jovanović, Bojan K Zlatković, Biljana M Nikolić, Gordana S Stojanović, Petar D Marin
Chemical compositions of needle essential oils of 27 taxa from the section Pinus, including 20 and 7 taxa of the subsections Pinus and Pinaster, respectively, were compared in order to determine chemotaxonomic significance of terpenes at infrageneric level. According to analysis of variance, six out of 31 studied terpene characters were characterized by a high level of significance, indicating statistically significant difference between the examined subsections. Agglomerative hierarchical cluster analysis has shown separation of eight groups, where representatives of subsect...
February 6, 2017: Chemistry & Biodiversity
https://www.readbyqxmd.com/read/28162767/transcriptome-profiling-of-the-australian-arid-land-plant-eremophila-serrulata-a-dc-druce-scrophulariaceae-for-the-identification-of-monoterpene-synthases
#18
Octavia Natascha Kracht, Ann-Christin Ammann, Julia Stockmann, Daniel Wibberg, Jörn Kalinowski, Markus Piotrowski, Russell Kerr, Thomas Brück, Robert Kourist
Plant terpenoids are a large and highly diverse class of metabolites with an important role in the immune defense. They find wide industrial application as active pharmaceutical ingredients, aroma and fragrance compounds. Several Eremophila sp. derived terpenoids have been documented. To elucidate the terpenoid metabolism, the transcriptome of juvenile and mature Eremophila serrulata (A.DC.) Druce (Scrophulariaceae) leaves was sequenced and a transcript library was generated. We report on the first transcriptomic dataset of an Eremophila plant...
February 2, 2017: Phytochemistry
https://www.readbyqxmd.com/read/28160379/spearmint-r2r3-myb-transcription-factor-msmyb-negatively-regulates-monoterpene-production-and-suppresses-the-expression-of-geranyl-diphosphate-synthase-large-subunit-msgpps-lsu
#19
Vaishnavi Amarr Reddy, Qian Wang, Niha Dhar, Nadimuthu Kumar, Prasanna Nori Venkatesh, Chakravarthy Rajan, Deepa Panicker, Vishweshwaran Sridhar, Hui-Zhu Mao, Rajani Sarojam
Many aromatic plants, like spearmint, produce valuable essential oils in specialized structures called peltate glandular trichomes (PGT). Understanding the regulatory mechanisms behind the production of these important secondary metabolites will help design new approaches to engineer them. Here, we identified a PGT-specific R2R3-MYB gene MsMYB, from comparative RNA-Seq data of spearmint, and functionally characterized it. Analysis of MsMYB-RNAi transgenic lines showed increased levels of monoterpenes and MsMYB-overexpressing lines exhibited decreased levels of monoterpenes...
February 3, 2017: Plant Biotechnology Journal
https://www.readbyqxmd.com/read/28157095/functional-connectivity-in-the-default-mode-network-is-reduced-in-association-with-nocturnal-awakening-in-mild-cognitive-impairment
#20
Andrew C McKinnon, Shantel L Duffy, Nathan E Cross, Zoe Terpening, Ron R Grunstein, Jim Lagopoulos, Jennifer Batchelor, Ian B Hickie, Simon J G Lewis, James M Shine, Sharon L Naismith
BACKGROUND: Sleep disturbance is prevalent in MCI, and is a risk factor for cognitive deterioration. OBJECTIVE: To identify functional connectivity deficits in the default mode network (DMN) in patients with mild cognitive impairment (MCI) and sleep disturbance, relative to MCIs with intact sleep. METHODS: Participants comprised 47 adults aged 55 years and over, recruited from the Healthy Brain Ageing Clinic at the Brain and Mind Centre, Sydney, Australia...
February 1, 2017: Journal of Alzheimer's Disease: JAD
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