keyword
MENU ▼
Read by QxMD icon Read
search

methyl ester

keyword
https://www.readbyqxmd.com/read/29343612/structural-and-functional-characterisation-of-the-cytochrome-p450-enzyme-cyp268a2-from-mycobacterium-marinum
#1
Stella A Child, Elise F Naumann, John B Bruning, Stephen G Bell
Members of the cytochrome P450 monooxygenase family CYP268 are found across a broad range of Mycobacterium species including the pathogens Mycobacterium avium, M. colombiense,M. kansasii and Mmarinum CYP268A2, from M. marinum , which is the first member of this family to be studied, was purified and characterised. CYP268A2 was found to bind a variety of substrates with high affinity, including branched and straight-chain fatty acids (C10-C12), acetate esters, and aromatic compounds. The enzyme was also found to bind phenylimidazole inhibitors but not larger azoles, such as ketoconazole...
January 17, 2018: Biochemical Journal
https://www.readbyqxmd.com/read/29341612/stabilization-of-nabh4-in-methanol-using-a-catalytic-amount-of-naome-reduction-of-esters-and-lactones-at-room-temperature-without-solvent-induced-loss-of-hydride
#2
Prasanth C P, Ebbin Joseph, Abhijith A, Nair D S, Ibrahim Ibnusaud, Jevgenij Raskatov, Bakthan Singaram
Rapid reaction of NaBH4 with MeOH precludes its use as a solvent for large-scale ester reductions. We have now learned that a catalytic amount of NaOMe (5 mol %) stabilizes NaBH4 solutions in methanol at 25 °C and permits the use of these solutions for the reduction of esters to alcohols. The generality of this reduction method was demonstrated using 22 esters including esters of naturally occurring chiral γ-butyrolactone containing dicarboxylic acids. This method permits the chemoselective reductions of esters in the presence of cyano and nitro groups and the reductive cyclization of a pyrrolidinedione ester to a fused five-membered furo[2,3-b]pyrrole and a (-)-crispine A analogue in high optical and chemical yields...
January 17, 2018: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/29339442/specific-substrate-for-the-assay-of-lysosomal-acid-lipase
#3
Sophia Masi, Naveen Chennamaneni, Frantisek Turecek, C Ronald Scott, Michael H Gelb
BACKGROUND: Deficiency of lysosomal acid lipase (LAL) causes Wolman disease and cholesterol ester storage disease. With the recent introduction of enzyme replacement therapy to manage LAL deficiency comes the need for a reliable assay of LAL enzymatic activity that can be applied to dried blood spots (DBS). METHODS: We prepared and tested a library of analogs of palmitoyl 4-methylumbelifferyl esters to find a highly active and specific substrate for LAL in DBS. The LAL assay was optimized leading to both LC-MS/MS and fluorometric assay of LAL...
January 16, 2018: Clinical Chemistry
https://www.readbyqxmd.com/read/29338423/production-of-thermostable-multiple-enzymes-from-bacillus-amyloliquefaciens-kub29
#4
Kubendran Devaraj, Salma Aathika, Karthik Periyasamy, Premkumar Manickam Periyaraman, Shanmugam Palaniyandi, Sivanesan Subramanian
A strain of Bacillus amyloliquefaciens KUB29 was identified by 16S ribosomal RNA sequencing (Genbank: MF772779.1). Production of thermostable protease, amylase and lipase were done by the isolated strain. The produced enzymes were partially purified by ammonium precipitation followed by dialysis process. Protease and lipase enzymes are effectively used in bio-oil extraction from proteinaceous sample followed by transesterification to produce methyl ester. Amylase enzyme is widely used in food and laundry industry...
January 16, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29338189/three-phase-morphology-evolution-in-sequentially-solution-processed-polymer-photodetector-toward-low-dark-current-and-high-photodetectivity
#5
Hanyu Wang, Shen Xing, Yifan Zheng, Jaemin Kong, Junsheng Yu, André D Taylor
Sequentially solution-processed polymer photodetectors (SSP PPDs) based on poly(3-hexylthiophene-2,5-diyl) (P3HT)/[6,6]-phenyl C71-butyric acid methyl ester (PC71BM) are fabricated by depositing the top layers of PC71BM from an appropriate cosolvent of 2-chlorophenol (2-CP)/o-dichlorobenzene (ODCB) onto the predeposited bottom layers of P3HT. By adjusting the ratio of 2-CP/ODCB in the top PC71BM layers, the resulting SSP PPD shows a decreased dark current and an increased photocurrent, leading to a maximum detectivity of 1...
January 17, 2018: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29338174/solution-processable-zno-carbon-quantum-dots-electron-extraction-layer-for-highly-efficient-polymer-solar-cells
#6
Ruqin Zhang, Min Zhao, Zhongqiang Wang, Zongtao Wang, Bo Zhao, Yanqin Miao, Yingjuan Zhou, Hua Wang, Yuying Hao, Guo Chen, Furong Zhu
In this work, we report the effort to develop high efficiency inverted polymer solar cells (PSCs) by applying a solution processable bilayer ZnO/carbon quantum dots (C-QDs) electron extraction layer (EEL). It is shownthat the use of the bilayerEEL helps to suppress the exciton quenching by passivating the ZnO surface defects in the EEL, leading to an enhanced exciton dissociation, reduced charge recombinationand more efficient charge extraction probability, and thereby achieving high power conversion efficiency (PCE)...
January 17, 2018: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29335865/beneficial-effect-of-berberis-amurensis-rupr-on-penile-erection
#7
Rui Tan, Yun Jung Lee, Kyung Woo Cho, Dae Gill Kang, Ho Sub Lee
OBJECTIVE: To investigate whether the methanol extract of Berberis amurensis Rupr. (BAR) augments penile erection using in vitro and in vivo experiments. METHODS: The ex vivo study used corpus cavernosum strips prepared from adult male New Zealand White rabbits. In in vivo studies for intracavernous pressure (ICP), blood pressure, mean arterial pressure (MAP), and increase of peak ICP were continuously monitored during electrical stimulation of Sprague-Dawley rats...
January 15, 2018: Chinese Journal of Integrative Medicine
https://www.readbyqxmd.com/read/29335226/genomic-and-metabolic-characterization-of-spoilage-associated-pseudomonas-species
#8
Tamsyn Stanborough, Narelle Fegan, Shane M Powell, Tanoj Singh, Mark Tamplin, P Scott Chandry
Pseudomonas are common spoilage agents of aerobically stored fresh foods. Their ability to cause spoilage is species- and may be strain-specific. To improve our understanding of the meat and milk spoilage agents Pseudomonas fragi and Pseudomonas lundensis, we sequenced the genomes of 12 P. fragi and seven P. lundensis isolates. These genomes provided a dataset for genomic analyses. Key volatile organic compounds (VOCs) produced or metabolised by the isolates were determined during their growth on a beef paste and where possible, metabolic activity was associated with gene repertoire...
January 5, 2018: International Journal of Food Microbiology
https://www.readbyqxmd.com/read/29335181/enhancing-the-photovoltaic-performance-of-bulk-heterojunction-polymer-solar-cells-by-adding-rhodamine-b-laser-dye-as-co-sensitizer
#9
Sholeh Kazemifard, Leila Naji, Faramarz Afshar Taromi
Ternary blend (TB) strategy has been considered as an effective method to enhance the photovoltaic performance of bulk heterojunction (BHJ) polymer solar cells (PSCs). Here, we report on TB-based PSCs containing two donor materials; poly-3-hexylthiophene (P3HT) and Rhodamine B (RhB) laser organic dye, and [6,6]-phenyl C61 butyric acid methyl ester (PC61BM) as an acceptor. The influence of RhB weight percentage and injection volume was extensively studied. To gain insight into the influences of RhB on the photovoltaic performance of PSCs, physicochemical and optical properties of TBs were compared with those of BHJ binary blend as a standard...
January 5, 2018: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/29333747/rapid-regioselective-living-ring-opening-metathesis-polymerization-of-bio-derivable-asymmetric-tricyclic-oxanorbornenes
#10
Mohamed Naguib, Tara L Schiller, Daniel J Keddie
The synthesis of a range of alkyl esters (methyl, n-butyl, and n-decyl) prepared via Steglich esterification of the thermodynamically controlled exo, exo Diels-Alder adduct of furfuryl alcohol and maleic anhydride is reported. Subsequent ring-opening metathesis polymerization of these bio-derivable tricyclic oxanorbornene analogs delivers polymers with targeted molar mass and low molar mass dispersity. The polymerizations are rapid with complete monomer conversion achieved within 15 min. Significantly, the presence of the cyclic lactone at the bridgehead of these monomers leads to polymers with high regioregularity (>85% head-to-tail) and high stereoregularity (>75% trans)...
January 15, 2018: Macromolecular Rapid Communications
https://www.readbyqxmd.com/read/29333618/age-associated-urethral-dysfunction-in-urethane-anesthetized-rats
#11
Ryu Kimura, Minoru Miyazato, Asuka Ashikari, Takuma Oshiro, Seiichi Saito
AIMS: We aimed to investigate the age-associated changes in movement coordination between the urinary bladder and the urethra in rats. METHODS: A total of 17 female Sprague-Dawley rats were used. The rats were divided into young (3 months old) and middle-aged (12-15 months old) groups. In both groups, isovolumetric cystometry and urethral perfusion pressure (UPP) measurements were performed under urethane anesthesia. After the rhythmic bladder contractions stabilized, L-arginine, a nitric oxide (NO) substrate (100 mg/kg), was administered intravenously in both groups...
January 15, 2018: Neurourology and Urodynamics
https://www.readbyqxmd.com/read/29333036/autonomic-receptors-and-nitric-oxide-involvements-in-mediating-vasorelaxation-effect-induced-by-syzygium-polyanthum-leaves-extract
#12
Azlini Ismail, Wan Amir Nizam Wan Ahmad
Context: Syzygium polyanthum (Wight) Walp leaves are traditionally used by Malays for treating hypertension. Our previous study showed that aqueous extract of S. polyanthum (AESP) and methanolic extract of S. polyanthum (MESP) extracts of S. polyanthum leaves significantly reduced blood pressure of normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). Aims: This study aimed to investigate their vasorelaxation potential and the possible involvement of autonomic receptors and nitric oxide in mediating their effect...
December 2017: Pharmacognosy Research
https://www.readbyqxmd.com/read/29332994/application-of-the-advanced-distillation-curve-method-to-the-comparison-of-diesel-fuel-oxygenates-2-5-7-10-tetraoxaundecane-tou-2-4-7-9-tetraoxadecane-tod-and-ethanol-fatty-acid-methyl-ester-fame-mixtures
#13
Jessica L Burger, Tara M Lovestead, Mark LaFollette, Thomas J Bruno
Although they are amongst the most efficient engine types, compression-ignition engines have difficulties achieving acceptable particulate emission and NOx formation. Indeed, catalytic after-treatment of diesel exhaust has become common and current efforts to reformulate diesel fuels have concentrated on the incorporation of oxygenates into the fuel. One of the best ways to characterize changes to a fuel upon the addition of oxygenates is to examine the volatility of the fuel mixture. In this paper, we present the volatility, as measured by the advanced distillation curve method, of a prototype diesel fuel with novel diesel fuel oxygenates: 2,5,7,10-tetraoxaundecane (TOU), 2,4,7,9-tetraoxadecane (TOD), and ethanol/fatty acid methyl ester (FAME) mixtures...
August 17, 2017: Energy & Fuels: An American Chemical Society Journal
https://www.readbyqxmd.com/read/29332217/a-novel-glucuronoyl-esterase-from-aspergillus-fumigatus-the-role-of-conserved-lys-residue-in-the-preference-for-4-o-methyl-glucuronoyl-esters
#14
Hung Hiep Huynh, Nozomi Ishii, Ichiro Matsuo, Manabu Arioka
Cellulose in plant cell walls is mainly covered by hemicellulose and lignin, and thus efficient removal of these components is thought to be a key step in the optimal utilization of lignocellulose. The recently discovered carbohydrate esterase (CE) 15 family of glucuronoyl esterases (GEs) which cleave the linkages between the free carboxyl group of D-glucuronic acid in hemicellulose and the benzyl groups in lignin residues could contribute to this process. Herein, we report the identification, functional expression, and enzymatic characterization of a GE, AfGE, from the filamentous fungus Aspergillus fumigatus...
January 14, 2018: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/29329648/preparation-and-physicochemical-characterization-of-t-oa-plga-microspheres
#15
Jing Fu, Xiao-Xu Dong, Zu-Ping Zeng, Xing-Bin Yin, Fa-Wei Li, Jian Ni
As the carrier of water-insoluble drugs, microspheres can play a role in increasing solubility and delaying releasing essence. The objective of this study was to improve the solubility and to delay the release of a newly discovered antitumor compound 3β-hydroxyolea-12-en-28-oic acid-3, 5, 6-trimethylpyrazin-2-methyl ester (T-OA). Early-stage preparation discovery concept (EPDC) was employed in the present study. The preparation, physicochemical characterization, and drug release properties of PLGA microspheres were evaluated...
December 2017: Chinese Journal of Natural Medicines
https://www.readbyqxmd.com/read/29329462/silibinin-from-silybum-marianum-stimulates-embryonic-stem-cell-vascular-differentiation-via-the-stat3-pi3-k-akt-axis-and-nitric-oxide
#16
Enas Hussein Ali, Fatemeh Sharifpanah, Maria Wartenberg, Heinrich Sauer
Silibinin, the bioactive compound of milk thistle (Silybum marianum), exerts tissue protective and regenerative effects that may include stem cell differentiation toward vascular cells. The purpose of the present study was to investigate whether silibinin stimulates blood vessel formation from mouse embryonic stem (ES) cells and to unravel the underlying signaling cascade. Vascular branching points were assessed by confocal laser scanning microscopy and computer-assisted image analysis of CD31-positive cell structures...
January 12, 2018: Planta Medica
https://www.readbyqxmd.com/read/29329269/design-synthesis-and-safener-activity-of-novel-methyl-r-n-benzoyl-dichloroacetyl-thiazolidine-4-carboxylates
#17
Li-Xia Zhao, Hao Wu, Yue-Li Zou, Qing-Rui Wang, Ying Fu, Chun-Yan Li, Fei Ye
A series of novel methyl (R)-N-benzoyl/dichloroacetyl-thiazolidine-4-carboxylates were designed by active substructure combination. The title compounds were synthesized using a one-pot route from l-cysteine methyl ester hydrochloride, acyl chloride, and ketones. All compounds were characterized by IR, ¹H NMR, 13C NMR, and HRMS. The structure of 4q was determined by X-ray crystallography. The biological tests showed that the title compounds protected maize from chlorimuron-ethyl injury to some extent. The ALS activity assay showed that the title compounds increased the ALS activity of maize inhibited by chlorimuron-ethyl...
January 12, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29327934/synthesis-of-pyrrole-2-carbaldehyde-derivatives-by-oxidative-annulation-and-direct-csp3-h-to-c%C3%A2-o-oxidation
#18
Xia Wu, Peng Zhao, Xiao Geng, Can Wang, Yan-Dong Wu, An-Xin Wu
An efficient and practical de novo synthesis of pyrrole-2-carbaldehyde skeletons featuring oxidative annulation and Csp3-H to C═O oxidation is presented, exemplified by the preparation of pyrrole-2-carbaldehyde derivatives from aryl methyl ketones, arylamines, and acetoacetate esters. Preliminary mechanistic investigations indicate that the aldehyde oxygen atom originates from oxygen. Moreover, the developed scalable approach provides a distinct advantage over traditional oxidative functionalization of C-H moieties, avoiding the use of stoichiometric quantities of hazardous oxidants...
January 12, 2018: Organic Letters
https://www.readbyqxmd.com/read/29325744/dextran-hydrogels-by-crosslinking-with-amino-acid-diamines-and-their-viscoelastic-properties
#19
Naphtali A O'Connor, Mihaela Jitianu, Greisly Nunez, Quentin Picard, Madeline Wong, David Akpatsu, Adam Negrin, Rajendra Gharbaran, Daniel Lugo, Sundus Shaker, Andrei Jitanu, Stephen Redenti
Amine functionalized polysaccharide hydrogels such as those based on chitosan are widely examined as biomaterials. Here we set out to develop a facile procedure for developing such hydrogels by crosslinking dextran with amino acid diamines. The dextran-amino acid gels were formed by the addition of the amino acid diamines to a dextran and epichlorohydrin solution once it became homogeneous. This was demonstrated with three amino acid diamines, lysine, lysine methyl ester, and cystine dimethyl ester. Hydrogel networks with albumin entrapped were also demonstrated...
January 8, 2018: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/29324381/comparative-study-of-diesel-and-biodiesel-exhausts-on-lung-oxidative-stress-and-genotoxicity-in-rats
#20
Thierry Douki, Cécile Corbière, David Preterre, Perrine J Martin, Valérie Lecureur, Véronique André, Yann Landkocz, Ivannah Pottier, Veronika Keravec, Olivier Fardel, Silvestre Moreira-Rebelo, Didier Pottier, Cathy Vendeville, Frédéric Dionnet, Pierre Gosset, Sylvain Billet, Christelle Monteil, François Sichel
The contribution of diesel exhaust to atmospheric pollution is a major concern for public health, especially in terms of occurrence of lung cancers. The present study aimed at addressing the toxic effects of a repeated exposure to these emissions in an animal study performed under strictly controlled conditions. Rats were repeatedly exposed to the exhaust of diesel engine. Parameters such as the presence of a particle filter or the use of gasoil containing rapeseed methyl ester were investigated. Various biological parameters were monitored in the lungs to assess the toxic and genotoxic effects of the exposure...
January 8, 2018: Environmental Pollution
keyword
keyword
68655
1
2
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"