Read by QxMD icon Read


Lina Castano-Duque, Kenneth W Loades, John F Tooker, Kathleen M Brown, W Paul Williams, Dawn S Luthe
Insect resistance against root herbivores like the western corn rootworm (WCR, Diabrotica virgifera virgifera) is not well understood in non-transgenic maize. We studied the responses of two American maize inbreds, Mp708 and Tx601, to WCR infestation using biomechanical, molecular, biochemical analyses, and laser ablation tomography. Previous studies performed on several inbreds indicated that these two maize genotypes differed in resistance to pests including fall armyworm (Spodoptera frugiperda) and WCR. Our data confirmed that Mp708 shows resistance against WCR, and demonstrates that the resistance mechanism is based in a multi-trait phenotype that includes increased resistance to cutting in nodal roots, stable root growth during insect infestation, constitutive and induced expression of known herbivore-defense genes, including ribosomal inhibitor protein 2 (rip2), terpene synthase 23 (tps23) and maize insect resistance cysteine protease-1 (mir1), as well high constitutive levels of jasmonic acid and production of (E)-β-caryophyllene...
November 18, 2017: Journal of Chemical Ecology
Onoja Samuel Okwudili, Nwachukwu Glory Chimaobi, Ezeja Maxwell Ikechukwu, Omeh Yusuf Ndukaku
Background The study evaluated phytochemical composition, antidiabetic, oral glucose tolerance test and in vitro antioxidant activities of hydromethanol extract of Paullinia pinnata root bark. Methods Cold maceration method was used in extract preparation and scavenging of 2,2-diphenyl-1-picrylhydrazyl radicals was used to evaluate antioxidant properties of the extract. Diabetes was induced with alloxan at the dose of 160 mg/kg. The antidiabetic activity of the extract was tested at doses of 50, 100 and 200 mg/kg, and glibenclamide was used as reference drug...
November 17, 2017: Journal of Complementary & Integrative Medicine
Matthew L Condakes, Kevin Hung, Stephen Harwood, Thomas J Maimone
We report the first chemical syntheses of both (-)-majucin and (-)-jiadifenoxolane A via 10 net oxidations from the ubiquitous terpene (+)-cedrol. Additionally, this approach allows for access to other majucin-type sesquiterpenes, like (-)-jiadifenolide, (-)-jiadifenin, and (-)-(1R,10S)-2-oxo-3,4-dehydroxyneomajucin (ODNM) along the synthetic pathway. Site-selective aliphatic C(sp3)-H bond oxidation reactions serve as the cornerstone of this work which offers access to highly oxidized natural products from an abundant and renewable terpene feedstock...
November 17, 2017: Journal of the American Chemical Society
Ana Margarida Ferro, Patrícia Ramos, Ângela Guerra, Paula Parreira, Teresa Brás, Olinda Guerreiro, Eliana Jerónimo, Carmen Capel, Juan Capel, Fernando J Yuste-Lisbona, Maria F Duarte, Rafael Lozano, M Margarida Oliveira, Sónia Gonçalves
Cynara cardunculus: L. represents a natural source of terpenic compounds, with the predominant molecule being cynaropicrin. Cynaropicrin is gaining interest since it has been correlated to anti-hyperlipidaemia, antispasmodic and cytotoxicity activity against leukocyte cancer cells. The objective of this work was to screen a collection of C. cardunculus, from different origins, for new allelic variants in germacrene A synthase (GAS) gene involved in the cynaropicrin biosynthesis and correlate them with improved cynaropicrin content and biological activities...
November 16, 2017: Molecular Genetics and Genomics: MGG
Akintayo Ogundajo, Anofi Tom Ashafa
Background: Ehretia cymosa Thonn. is a popular medicinal plant used in different parts of West Africa for the treatment of various ailments including diabetes mellitus. Objective: The current study investigates bioactive constituents and in vitro antioxidant and antidiabetic potentials of fractions from extract of E. cymosa. Materials and Methods: Phytochemical investigation and antioxidant assays were carried out using standard procedures...
October 2017: Pharmacognosy Magazine
Taís Vanessa Gabbay Alves, Russany Silva da Costa, Bahar Aliakbarian, Alessandro Alberto Casazza, Patrizia Perego, Mara Silvia Pinheiro Arruda, José Otávio Carréra Silva Júnior, Attilio Converti, Roseane Maria Ribeiro Costa
Processing of cocoa (Theobroma cacao L.) beans responsible for agricultural exports leads to large amounts of solid waste that were discarded, however, this one presents high contents of metabolites with biological activities. The major objective of this study was to valorise cocoa agroindustrial residue obtained by hydraulic pressing for extract rich in antioxidants. For it, the centesimal composition of residue was investigated, the green extraction was carried out from the residue after, the bioactive compounds, sugar contents and screaming by HPTLC were quantified for extract...
November 10, 2017: Natural Product Research
Jan Rinkel, Lukas Lauterbach, Jeroen Sidney Dickschat
A terpene synthase from the marine bacterium Streptomyces xinghaiensis was characterised, including a full structure elucidation of its products from various substrates and an in-depth investigation of the enzyme mechanism by isotopic labelling experiments, substrate and metal cofactor variations, and mutation experiments. The results revealed an interesting dependency of Mn2+ catalysis on the presence of Asp-217, a residue that is occupied by a highly conserved Glu in most other bacterial terpene synthases...
November 10, 2017: Angewandte Chemie
Sayed Asmat Ali Shah, Najeeb Akhter, Bibi Nazia Auckloo, Ishrat Khan, Yanbin Lu, Kuiwu Wang, Bin Wu, Yue-Wei Guo
Nowadays, various drugs on the market are becoming more and more resistant to numerous diseases, thus declining their efficacy for treatment purposes in human beings. Antibiotic resistance is one among the top listed threat around the world which eventually urged the discovery of new potent drugs followed by an increase in the number of deaths caused by cancer due to chemotherapy resistance as well. Accordingly, marine cyanobacteria, being the oldest prokaryotic microorganisms belonging to a monophyletic group, have proven themselves as being able to generate pharmaceutically important natural products...
November 10, 2017: Marine Drugs
Marietta Białoń, Teresa Krzyśko-Łupicka, Agnieszka Pik, Piotr P Wieczorek
This study addresses the chemical composition of some commercial essential oils (clove, juniper, oregano, and marjoram oils), as well as appropriate herbal extracts obtained in the process of cold maceration and their biological activity against selected Escherichia coli strains: E. coli ATTC 25922, E. coli ATTC 10536, and E. coli 127 isolated from poultry waste. On the basis of the gas chromatography-mass spectrometry (GCMS) analysis, it was found that the commercial essential oils revealed considerable differences in terms of the composition and diversity of terpenes, terpenoids and sesquiterpenes as compared with the extracts obtained from plant material...
November 10, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Pedro Romón, Domitila Aparicio, Francisco Palacios, Juan Carlos Iturrondobeitia, Thierry Hance, Arturo Goldarazena
Concentrations of four monoterpenes were determined in needles of Pinus radiata (D.Don) (Pinales: Pinaceae) trees that were attacked or nonattacked by Tomicus piniperda (L.) (Coleoptera: Scolytinae). Compounds were identified and quantified by gas chromatography-mass spectrometry. The mean ambient temperature was obtained using climate-recording data loggers. The effect of limonene on field aggregation was also evaluated at three limonene release rates using Lindgren attractant-baited traps and trap logs. Attacked trees produced less α-pinene in March, July, and November than nonattacked trees, less β-pinene in July and November, and less limonene from May to November...
September 1, 2017: Journal of Insect Science
David W Pratt, Brooks H Pate
Undoing the twist: Recent successful attempts to change the relative populations of two otherwise identical enantiomers of a large gas-phase molecule using resonant microwave fields are highlighted. Specifically, the population of a specific enantiomer of a chiral terpene could be enhanced relative to the other enantiomer by the application of a sequence of microwave pulses in a phase- and polarization-controlled manner.
November 8, 2017: Angewandte Chemie
Patil Shriniwas P, Kumbhar Subhash T
Several attempts have been made for green synthesis of silver nanoparticles (AgNPs) using different plant extracts. Present study revealed that, antioxidant, antibacterial and cytotoxic AgNPs were synthesized using terpenes-rich extract (TRE) of environmentally notorious Lantana camara L. leaves. AgNPs were characterized by advanced techniques like UV-Visible and Infra red spectroscopy; XRD, SEM techniques as terpenes coated sphere shaped NPs with average diameter 425 nm. Further, on evaluation, AgNPs were found to exhibit dose - dependent antioxidant potential, good to moderate antibacterial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa; and toxicity on Brine shrimp (A...
July 2017: Biochemistry and Biophysics Reports
Anllely G Gutiérrez-Rodríguez, Claudia Juárez-Portilla, Tatiana Olivares-Bañuelos, Rossana C Zepeda
Cancer is a major health problem worldwide and still lacks fully effective treatments. Therefore, alternative therapies, using natural products, have been proposed. Marine algae are an important component of the marine environment, with high biodiversity, and contain a huge number of functional compounds, including terpenes, polyphenols, phlorotannins, and polysaccharides, among others. These compounds have complex structures that have shown several biological activities, including anticancer activity, in several in vitro and in vivo models...
October 26, 2017: Drug Discovery Today
Anaí L Dos Santos, Allan Dos S Polidoro, Cláudia A L Cardoso, Margareth Batistote, Maria do Carmo Vieira, Rosângela A Jacques, Elina B Caramão
The present study investigated the essential oil obtained from Campomanesia guazumifolia (Cambess.) O. Berg, an aromatic plant used in Brazilian folk medicine. The chemical composition was performed by GC×GC/qMS. The antioxidant and antimicrobial activities were evaluated by DPPH and BCB and, MIC assays, respectively. Sixty-eight compounds were identified in the oil, where the major compounds were bicyclogermacrene (15%), globulol (5%) and spathulenol (5%). Sesquiterpene hydrocarbons (29 compounds) and oxygenated sesquiterpenes (20 compounds) were the most representative classes of terpenes...
November 5, 2017: Natural Product Research
Anna Wajs-Bonikowska, Łukasz Szoka, Ewa Karna, Anna Wiktorowska-Owczarek, Monika Sienkiewicz
The chemical composition, including the enantiomeric excess of the main terpenes, of essential oils from seeds and cones of Abies concolor was studied by chromatographic (GC) and spectroscopic methods (mass spectrometry, nuclear magnetic resonance), leading to the determination of 98 compounds. Essential oils were mainly composed of monoterpene hydrocarbons. The dominant volatiles of seed essential oil were: limonene (47 g/100 g, almost pure levorotary form) and α-pinene (40 g/100 g), while α-pinene (58 g/100 g), sabinene (11 g/100 g), and β-pinene (4...
November 2, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Roland D Kersten, Shoukou Lee, Daishi Fujita, Tomáš Pluskal, Susan Kram, Jennifer E Smith, Takahiro Iwai, Joseph P Noel, Makoto Fujita, Jing-Ke Weng
Sesquiterpene scaffolds are the core backbones of many medicinally and industrially important natural products. A plethora of sesquiterpene synthases, widely present in bacteria, fungi, and plants, catalyze the formation of these intricate structures often with multiple stereocenters starting from linear farnesyl diphosphate substrates. Recent advances in next-generation sequencing and metabolomics technologies have greatly facilitated gene discovery for sesquiterpene synthases. However, a major bottleneck limits biochemical characterization of recombinant sesquiterpene synthases: the absolute structural elucidation of the derived sesquiterpene products...
November 14, 2017: Journal of the American Chemical Society
Monica Borghi, De-Yu Xie
CsTPS1 encodes for a monoterpene synthase that contributes to the emission of a blend of volatile compounds emitted from flowers of Camelina sativa. The work describes the in vitro characterization of a monoterpene synthase and its regulatory region that we cloned from Camelina sativa (Camelina). Here, we named this gene as C. sativa terpene synthase 1 (CsTPS1). In vitro experiments performed with the CsTPS1 protein after expression and purification from Escherichia coli (E. coli) showed production of a blend of monoterpene volatile organic compounds, of which the emission was also detected in the floral bouquet of wild-type Camelina plants...
October 26, 2017: Planta
Junko Yaegashi, James Kirby, Masakazu Ito, Jian Sun, Tanmoy Dutta, Mona Mirsiaghi, Eric R Sundstrom, Alberto Rodriguez, Edward Baidoo, Deepti Tanjore, Todd Pray, Kenneth Sale, Seema Singh, Jay D Keasling, Blake A Simmons, Steven W Singer, Jon K Magnuson, Adam P Arkin, Jeffrey M Skerker, John M Gladden
BACKGROUND: Economical conversion of lignocellulosic biomass into biofuels and bioproducts is central to the establishment of a robust bioeconomy. This requires a conversion host that is able to both efficiently assimilate the major lignocellulose-derived carbon sources and divert their metabolites toward specific bioproducts. RESULTS: In this study, the carotenogenic yeast Rhodosporidium toruloides was examined for its ability to convert lignocellulose into two non-native sesquiterpenes with biofuel (bisabolene) and pharmaceutical (amorphadiene) applications...
2017: Biotechnology for Biofuels
Basma Najar, Luisa Pistelli, Claudio Cervelli, Gelsomina Fico, Claudia Giuliani
The volatile profiles (VOC) and the essential oil (EO) composition from the aerial parts of Salvia broussonetii were analysed. Sesquiterpene hydrocarbons dominate the VOCs from leaves (95.7%) and flowers (67.6%), followed by monoterpene hydrocarbons (2.6 and 29.7%, respectively). The main common compounds are germacrene D, β-bourbonene, α-pinene, α-copaene and α-gurjunene, even if with divergent relative abundances. In the leaf EOs the sesquiterpenes prevail, even if not overwhelmingly (about 50.0%), followed by monoterpenes (23...
October 26, 2017: Natural Product Research
Qidong Jia, Tobias G Köllner, Jonathan Gershenzon, Feng Chen
Terpenes constitute a large class of plant secondary metabolites. It was once presumed that these compounds are biosynthesized by typical plant terpene synthases in all land plants. This view has changed with the identification of a new group of terpene synthase genes called MTPSLs for microbial terpene synthase-like genes. MTPSLs are structurally and phylogenetically more related to bacterial and fungal terpene synthases than to typical plant terpene synthases. They are widely distributed in nonseed plants but absent in seed plants and green algae...
October 20, 2017: Trends in Plant Science
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"