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https://www.readbyqxmd.com/read/27912967/qualitative-analysis-of-copaifera-oleoresin-using-comprehensive-two-dimensional-gas-chromatography-and-gas-chromatography-with-classical-and-cold-electron-ionisation-mass-spectrometry
#1
Yong Foo Wong, Thais M Uekane, Claudia M Rezende, Humberto R Bizzo, Philip J Marriott
Improved separation of both sesquiterpenes and diterpenic acids in Copaifera multijuga Hayne oleoresin, is demonstrated by using comprehensive two-dimensional gas chromatography (GC×GC) coupled to accurate mass time-of-flight mass spectrometry (accTOFMS). GC×GC separation employs polar phases (including ionic liquid phases) as the first dimension ((1)D) column, combined with a lower polarity (2)D phase. Elution temperatures (Te) of diterpenic acids (in methyl ester form, DAME) increased as the (1)D McReynolds' polarity value of the column phase decreased...
November 22, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27911807/enhanced-limonene-production-in-cyanobacteria-reveals-photosynthesis-limitations
#2
Xin Wang, Wei Liu, Changpeng Xin, Yi Zheng, Yanbing Cheng, Su Sun, Runze Li, Xin-Guang Zhu, Susie Y Dai, Peter M Rentzepis, Joshua S Yuan
Terpenes are the major secondary metabolites produced by plants, and have diverse industrial applications as pharmaceuticals, fragrance, solvents, and biofuels. Cyanobacteria are equipped with efficient carbon fixation mechanism, and are ideal cell factories to produce various fuel and chemical products. Past efforts to produce terpenes in photosynthetic organisms have gained only limited success. Here we engineered the cyanobacterium Synechococcus elongatus PCC 7942 to efficiently produce limonene through modeling guided study...
November 23, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27911440/the-prey-s-scent-volatile-organic-compound-mediated-interactions-between-soil-bacteria-and-their-protist-predators
#3
Kristin Schulz-Bohm, Stefan Geisen, E R Jasper Wubs, Chunxu Song, Wietse de Boer, Paolina Garbeva
Protists are major predators of bacteria in soils. However, it remains unknown how protists sense their prey in this highly complex environment. Here, we investigated whether volatile organic compounds (VOCs) of six phylogenetic distinct soil bacteria affect the performance of three different soil protists and how that relates to direct feeding interactions. We observed that most bacteria affected protist activity by VOCs. However, the response of protists to the VOCs was strongly dependent on both the bacterial and protist interacting partner...
December 2, 2016: ISME Journal
https://www.readbyqxmd.com/read/27909855/conifer-monoterpene-chemistry-during-an-outbreak-enhances-consumption-and-immune-response-of-an-eruptive-folivore
#4
Amy M Trowbridge, M Deane Bowers, Russell K Monson
Changes in the chemical composition of plant defense compounds during herbivory can impact herbivore resource allocation patterns and thereby herbivore survival, growth, and immune response against endoparasitoid infection. Few studies have investigated folivore responses to changes in plant chemistry that occur under outbreak conditions in mature conifer systems. Using data from an earlier observational field study, we carried out laboratory bioassays to test how variation in monoterpenes in piñon pine trees (Pinus edulis, Pinaceae) during an outbreak affects growth, consumption, and immune response of a specialist herbivore, the Southwestern tiger moth (Lophocampa ingens, Arctiidae)...
December 1, 2016: Journal of Chemical Ecology
https://www.readbyqxmd.com/read/27903443/biochemical-and-genetic-basis-of-orsellinic-acid-biosynthesis-and-prenylation-in-a-stereaceous-basidiomycete
#5
Jana Braesel, Janis Fricke, Daniel Schwenk, Dirk Hoffmeister
The prenylphenols are a class of natural products that have been frequently isolated from basidiomycetes, e.g., from the genus Stereum (false turkey tail fungi) and other Russulales as well as from ascomycetes. Biosynthetically, these compounds are considered hybrids, as the orsellinic acid moiety is a polyketide and the prenyl side chain originates from the terpene metabolism, although no literature on the genetic and biochemical background of the biosynthesis is available. In a stereaceous basidiomycete, referred to as BY1, a new prenylphenol, now termed cloquetin, was identified and its structure elucidated by mass spectrometry and nuclear magnetic resonance spectroscopy...
November 26, 2016: Fungal Genetics and Biology: FG & B
https://www.readbyqxmd.com/read/27902914/inactivation-of-avian-influenza-virus-in-nonpelleted-chicken-feed
#6
H Toro, V L van Santen, C Breedlove
Corn stored outside could become contaminated with avian influenza virus (AIV) from wild bird droppings. AIV-contaminated ingredients could pass into the poultry flocks in nonpelleted chicken feed. The efficacy of two disinfectants at inactivating AIV in chicken feed was evaluated. Both Termin-8 (a blend of formaldehyde, propionic acid, terpenes, and surfactant) and Finio (a blend of approved phytochemicals and carboxylic acids) effectively inactivated AIV in chicken feed. Because stability of infectious AIV in chicken feed is limited, we evaluated addition of protein (skim milk powder) to the virus suspension...
December 2016: Avian Diseases
https://www.readbyqxmd.com/read/27896835/contact-sensitization-to-limonene-and-linalool-hydroperoxides-in-spain-a-geidac-prospective-study
#7
Gustavo Deza, Begoña García-Bravo, Juan F Silvestre, Maria A Pastor-Nieto, Ricardo González-Pérez, Felipe Heras-Mendaza, Pedro Mercader, Virginia Fernández-Redondo, Bo Niklasson, Ana M Giménez-Arnau
BACKGROUND: Limonene and linalool are common fragrance terpenes widely used in cosmetic, household and hygiene products. Their primary oxidation products formed after air exposure, the hydroperoxides, have been recognized as important contact haptens. OBJECTIVES: To investigate the prevalence of contact allergy to hydroperoxides of limonene (Lim-OOHs) and hydroperoxides of linalool (Lin-OOHs) in Spain, and to define the optimal concentration for screening in consecutive patients...
November 29, 2016: Contact Dermatitis
https://www.readbyqxmd.com/read/27896554/emission-of-volatile-compounds-from-apple-plants-infested-with-pandemis-heparana-larvae-antennal-response-of-conspecific-adults-and-preliminary-field-trial
#8
Valentino Giacomuzzi, Luca Cappellin, Iuliia Khomenko, Franco Biasioli, Stefan Schütz, Marco Tasin, Alan L Knight, Sergio Angeli
This study investigated the volatile emission from apple (Malus x domestica Borkh., cv. Golden Delicious) foliage that was either intact, mechanically-damaged, or exposed to larval feeding by Pandemis heparana (Denis and Schiffermüller) (Lepidoptera: Tortricidae). Volatiles were collected by closed-loop-stripping-analysis and characterized by gas chromatography-mass spectrometry in three time periods: after 1 h and again 24 and 48 h later. Volatiles for all treatments also were monitored continuously over a 72-h period by the use of proton transfer reaction - time of flight-mass spectrometry (PTR-ToF-MS)...
November 28, 2016: Journal of Chemical Ecology
https://www.readbyqxmd.com/read/27892539/chemotypic-variation-in-terpenes-emitted-from-storage-pools-influences-early-aphid-colonisation-on-tansy
#9
Mary V Clancy, Sharon E Zytynska, Matthias Senft, Wolfgang W Weisser, Jörg-Peter Schnitzler
Tansy plants (Tanacetum vulgare L.) exhibit high chemical variation, particularly in mono- and sesquiterpenes that are stored in specialised glands on the plant surface. In the present work we investigated the effects of terpene chemotypes on Metopeurum fuscoviride, an aphid species specialised on tansy, and their tending ants, at the field scale. Previous studies have chemotyped tansy by assessing dominant compounds; here we propose a method of chemotyping using all volatile compounds that are likely emitted from the storage glands...
November 28, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27888805/effects-of-abies-sibirica-terpenes-on-cancer-and-aging-associated-pathways-in-human-cells
#10
Anna Kudryavtseva, George Krasnov, Anastasiya Lipatova, Boris Alekseev, Faniya Maganova, Mikhail Shaposhnikov, Maria Fedorova, Anastasiya Snezhkina, Alexey Moskalev
A large number of terpenoids exhibit potential geroprotector and anti-cancer properties. Here, we studied whole transcriptomic effects of Abisil, the extract of fir (Abies sibirica) terpenes, on normal and cancer cell lines. We used early passaged and senescent none-immortalized fibroblasts as cellular aging models. It was revealed that in normal fibroblasts, terpenes induced genes of stress response, apoptosis regulation and tissue regeneration. The restoration of the expression level of some prolongevity genes after fir extract treatment was shown in old cells...
November 19, 2016: Oncotarget
https://www.readbyqxmd.com/read/27883995/natural-terpenes-influence-the-activity-of-antibiotics-against-isolated-mycobacterium-tuberculosis
#11
Elwira Sieniawska, Marta Swatko-Ossor, Rafał Sawicki, Krystyna Skalicka-Woźniak, Grazyna Ginalska
No abstract text is available yet for this article.
November 23, 2016: Medical Principles and Practice: International Journal of the Kuwait University, Health Science Centre
https://www.readbyqxmd.com/read/27881165/comparative-analysis-of-four-terpenoids-in-root-and-cortex-of-tripterygium-wilfordii-radix-by-different-drying-methods
#12
Tuanjie Wang, Fei Shen, Shulan Su, Yongliang Bai, Sheng Guo, Hui Yan, Tao Ji, Yanyan Wang, Dawei Qian, Jin-Ao Duan
BACKGROUND: Tripterygium wilfordii Radix, a well-known traditional medicine in china which is used for treatment of inflammation, pain, tumor and immune regulation for centuries in china, accompany with the serious toxic side effects. This study was carried out for simultaneously analyzing the four main components (triptolide, triptophenolide, demethylzeylasteral and celastrol) in Tripterygium wilfordii Radix under different drying processes, which was important for reducing the toxicity and quality control of Tripterygium wilfordii Radix in future...
November 23, 2016: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/27876209/synthesis-and-biological-evaluation-against-mycobacterium-tuberculosis-and-leishmania-amazonensis-of-a-series-of-diaminated-terpenoids
#13
Dijovani Batista Dos Reis, Thalita Cristina Alves Souza, Maria Cristina S Lourenço, Mauro Vieira de Almeida, Adriano Barbosa, Iriane Eger, Mauricio Frota Saraiva
We report the synthesis of a series of diaminated terpenoids containing, as side-chain of the diamine core, the "head-to-tail" prenyl derivatives, with amino amino spacers of variable length. In vitro biological activity of these compounds was evaluated against Mycobacterium tuberculosis and Leishmania amazonensis, and the structure-activity relationships are discussed. Different biological results were observed depending on the terpenic side-chain length. The best results were obtained for trans,trans-farnesol derivatives...
November 18, 2016: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/27872812/anti-inflammatory-effects-of-the-essential-oils-of-ginger-zingiber-officinale-roscoe-in-experimental-rheumatoid-arthritis
#14
Janet L Funk, Jennifer B Frye, Janice N Oyarzo, Jianling Chen, Huaping Zhang, Barbara N Timmermann
Ginger and its extracts have been used traditionally as anti-inflammatory remedies, with a particular focus on the medicinal properties of its phenolic secondary metabolites, the gingerols. Consistent with these uses, potent anti-arthritic effects of gingerol-containing extracts were previously demonstrated by our laboratory using an experimental model of rheumatoid arthritis, streptococcal cell wall (SCW)-induced arthritis. In this study, anti-inflammatory effects of ginger's other secondary metabolites, the essential oils (GEO), which contain terpenes with reported phytoestrogenic activity, were assessed in female Lewis rats with SCW-induced arthritis...
July 2016: PharmaNutrition
https://www.readbyqxmd.com/read/27869784/phytochemical-profiling-of-flavonoids-phenolic-acids-terpenoids-and-volatile-fraction-of-a-rosemary-rosmarinus-officinalis-l-extract
#15
Pedro Mena, Martina Cirlini, Michele Tassotti, Kelli A Herrlinger, Chiara Dall'Asta, Daniele Del Rio
This paper presents a comprehensive analysis of the phytochemical profile of a proprietary rosemary (Rosmarinus officinalis L.) extract rich in carnosic acid. A characterization of the (poly)phenolic and volatile fractions of the extract was carried out using mass spectrometric techniques. The (poly)phenolic composition was assessed by ultra-high performance liquid chromatography-electrospray ionization-mass spectrometry (UHPLC-ESI-MS(n)) and a total of 57 compounds were tentatively identified and quantified, 14 of these being detected in rosemary extract for the first time...
November 19, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/27868090/extraction-and-analysis-of-terpenes-terpenoids
#16
Zuodong Jiang, Chase Kempinski, Joe Chappell
Terpenes/terpenoids constitute one of the largest classes of natural products, this is due to the incredible chemical diversity that can arise from the biochemical transformations of the relatively simple prenyl diphosphate starter units. All terpenes/terpenoids comprise a hydrocarbon backbone that is generated from the various length prenyl diphosphates (a polymer chain of prenyl units). Upon ionization (removal) of the diphosphate group, the remaining allylic carbocation intermediates can be coaxed down complex chemical cascades leading to diverse linear and cyclized hydrocarbon backbones, which can then be further modified with a wide range of functional groups (e...
2016: Current Protocols in Plant Biology
https://www.readbyqxmd.com/read/27866997/recovery-of-metallic-concentrations-from-waste-printed-circuit-boards-via-reverse-floatation
#17
Jingfeng He, Chenlong Duan
Efficient disposal of waste printed circuit boards (PCBs) is favorable toward recovering valuable components and reducing pollution. Reverse floatation was used to recover metallic concentrations from waste PCBs. Basic properties and mineralogical characteristics of raw PCBs were tested and analyzed. Results indicated that the grade of metallic concentrations declined as the size fraction of PCBs decreased. The major metallic elements found in PCBs were Cu, Pb, and Sn, as well as trace elements were also found in fine PCB particles...
November 17, 2016: Waste Management
https://www.readbyqxmd.com/read/27866741/assessment-of-indoor-air-quality-in-office-buildings-across-europe-the-officair-study
#18
Corinne Mandin, Marilena Trantallidi, Andrea Cattaneo, Nuno Canha, Victor G Mihucz, Tamás Szigeti, Rosanna Mabilia, Erica Perreca, Andrea Spinazzè, Serena Fossati, Yvonne De Kluizenaar, Eric Cornelissen, Ioannis Sakellaris, Dikaia Saraga, Otto Hänninen, Eduardo De Oliveira Fernandes, Gabriela Ventura, Peder Wolkoff, Paolo Carrer, John Bartzis
The European project OFFICAIR aimed to broaden the existing knowledge regarding indoor air quality (IAQ) in modern office buildings, i.e., recently built or refurbished buildings. Thirty-seven office buildings participated in the summer campaign (2012), and thirty-five participated in the winter campaign (2012-2013). Four rooms were investigated per building. The target pollutants were twelve volatile organic compounds, seven aldehydes, ozone, nitrogen dioxide and particulate matter with aerodynamic diameter <2...
November 17, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27862766/terpene-cyclases-from-social-amoebae
#19
Patrick Rabe, Jan Rinkel, Britta Nubbemeyer, Tobias G Köllner, Feng Chen, Jeroen S Dickschat
Genome sequences of social amoebae reveal the presence of terpene cyclases (TCs) in these organisms. Two TCs from Dictyostelium discoideum converted farnesyl diphosphate into (2S,3R,6S,9S)-(-)-protoillud-7-ene and (3S)-(+)-asterisca-2(9),6-diene. The enzyme mechanisms and EI-MS fragmentations of the products were studied by labeling experiments.
November 10, 2016: Angewandte Chemie
https://www.readbyqxmd.com/read/27860109/assembly-of-terpenoid-cores-by-a-simple-tunable-strategy
#20
Ouidad Lahtigui, Fabien Emmetiere, Wei Zhang, Liban Jirmo, Samira Toledo-Roy, John C Hershberger, Jocelyn M Macho, Alexander J Grenning
Oxygenated, polycyclic terpenoid natural products have important biological activities. Although total synthesis of such terpenes is widely studied, synthetic strategies that allow for controlled placement of oxygen atoms and other functionality remains a challenge. Herein, we present a simple, scalable, and tunable synthetic strategy to assemble terpenoid-like polycycloalkanes from cycloalkanones, malononitrile, and allylic electrophiles, abundantly available reagent classes.
November 17, 2016: Angewandte Chemie
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