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Eduardo Dellacassa, Oriol Trenchs, Laura Fariña, Florencia Debernardis, Gabriel Perez, Eduardo Boido, Francisco Carrau
A pineapple vinification process was conducted through inoculated and spontaneous fermentation to develop a process suitable for a quality beverage during two successive vintages in Huambo, Angola. Wines obtained with the conventional Saccharomyces cerevisiae strain, were analysed by gas chromatography, and a total of 61 volatile constituents were detected in the volatile fraction and 18 as glycosidically bound aroma compounds. Concentration levels of carbonyl and sulphur compounds were in agreement with the limited information reported about pineapple fruits of other regions...
October 13, 2016: International Journal of Food Microbiology
Yu-Chun Wang, Chitsan Lin, Yu-Kai Lin, Ya-Fen Wang, Wei-Huang Weng, Yi-Ming Kuo
This study evaluates the effects of a sampling strategy that includes the sampling season, time period, ambient environment, and location on determining the concentrations and species of ambient volatile organic compounds (VOCs) that may affect children in primary schools. Air samples were collected from playgrounds in primary schools, with four sites near an oil refinery plant in Taoyuan and two sites in Zhongli (one site near a bus terminal and the other site in a suburban area) in Taiwan. The samples were obtained on eight occasions from August 2010 to June 2011...
October 26, 2016: Environmental Science. Processes & Impacts
Dongjun Qin, Weiwei Wang, Hu Lei, Hao Luo, Haiyan Cai, Caixia Tang, Yunzhao Wu, Yingying Wang, Jin Jin, Weilie Xiao, Tongdan Wang, Chunmin Ma, Hanzhang Xu, Jinfu Zhang, Fenghou Gao, Yingli Wu
Deubiquitinating enzyme USP7 has been involved in the pathogenesis and progression of several cancers. Targeting USP7 is becoming an attractive strategy for cancer therapy. In this study, we identified synthetic triterpenoid C-28 methyl ester of 2-cyano-3, 12-dioxoolen-1, 9-dien-28-oic acid (CDDO-Me) as a novel inhibitor of USP7 but not of other cysteine proteases such as cathepsin B and cathepsin D. CDDO-Me inhibits USP7 activity via a mechanism that is independent of the presence of α, β-unsaturated ketones...
October 21, 2016: Oncotarget
Huiqiao Wang, Zhong Wang, Hongchun Huang, Jiajing Tan, Kun Xu
An efficient and practical (hetero)benzylic sp(3) C-H oxidation method has been developed. Notably, this user-friendly protocol employs inexpensive potassium tert-butoxide (KO(t)Bu) as a promoter and proceeds under mild conditions using oxygen as the oxidant. A large variety of oxidation products were prepared in good to excellent yields. The utility of this "green" methodology was further demonstrated by the scale-up preparation of a biologically valued molecule.
October 25, 2016: Organic Letters
Timothy R Valentic, David R Jackson, Sean F Brady, Shiou-Chuan Sheryl Tsai
Arixanthomycins are pentangular polyphenols (PP) with potent antiproliferative activities that were discovered through the heterologous expression of environmental DNA-derived gene clusters. The biosynthesis of arixanthomycin and other PPs is unusual, because it requires several novel type II polyketide synthase (PKS) enzymes for its complete maturation. Most type II PKSs contain a ketoreductase (KR) that mediates the C7-C12 first ring cyclization and C9-reduction. In contrast, based on previous studies of product analysis and genome mining, the arixanthomycin (ARX) gene cluster like harbors a C11-reducing ketoreductase (ARX 27), a C9-C14 first-ring aromatase/cyclase (ARX 19), and an unprecedented C-17 and C-19 reducing KR (ARX 21)...
October 25, 2016: ACS Chemical Biology
Pengfei Li, Jindian Duan, Yuyu Cheng, Jing Cheng, Rou Li
A new method has been developed for the organocatalytic enantioselective benzylation and aldol-hemiacetalization of α,β-unsaturated trifluoromethyl ketones with toluene derivatives in the presence of a tertiary amine-thiourea catalyst. This method represents a facile and efficient strategy for the asymmetric synthesis of optically active 3,4-dihydroisocoumarins bearing a trifluoromethylated tetrasubstituted carbon stereocenter with high enantioselectivity. Notably, this strategy was used to synthesize several chiral trifluoromethylated analogues of typharin with high efficiency...
October 25, 2016: Chemistry: a European Journal
Aneta M Białkowska
2,3-Butanediol (2,3-BD) is a promising bulk chemical with a potentially wide range of applications e.g., in the manufacture of printing inks, perfumes, synthetic rubber, fumigants, antifreeze agents, fuel additives, foodstuffs and pharmaceuticals. Its high heating value and ability to increase the octane number of fuels make 2,3-BD a promising drop-in fuel. It can also be converted to methyl-ethyl ketone (MEK), which is considered an effective liquid fuel additive. After combination with MEK and hydrogenation reaction, 2,3-BD can be converted to octane, which is used to produce high-quality aviation fuel...
December 2016: World Journal of Microbiology & Biotechnology
Min Wang, Shan Xu, Chunjiang Wu, Xiaobo Liu, Hong Tao, Yanli Huang, Yongchan Liu, Pengwu Zheng, Wufu Zhu
Two series of sorafenib derivatives (N-methylpicolinamide-4-oxy) chalcones (5a-o, 7a-e) were synthesized and characterized by NMR and MS. All of the target compounds were evaluated for the cytotoxicity against A549, HepG2, MCF-7, and PC-3 cancer cell lines and some selected compounds were further evaluated for the activity against VEGFR-2/KDR and BRAF kinases. The results indicated that all the compounds showed moderate to good antitumor activity, and the compound 5c showed well cytotoxic activity against HepG2, MCF-7 and PC-3 cell lines with IC50 values of 0...
October 12, 2016: Bioorganic & Medicinal Chemistry Letters
Abdul Hameed, Mariya Al-Rashida, Maliha Uroos, Syed Ali, Khalid M Khan
Schiff bases are synthetically accessible and structurally diverse compounds, typically obtained by facile condensation between an aldehyde, or a ketone with primary amines. Schiff bases contain an azomethine (-C=N-) linkage that stitches together two or more biologically active aromatic/heterocyclic scaffolds to form various molecular hybrids with interesting biological properties. Schiff bases are versatile metal complexing agents and have been known to coordinate all metals to form stable metal complexes with vast therapeutic applications...
October 24, 2016: Expert Opinion on Therapeutic Patents
N Almenara, L Ibarlucea, C Mendicute-Fierro, J M Seco, A Rodríguez-Diéguez, M A Garralda, M A Huertos
[RhCl(NCO)(nbyl)(PR3)] (nbyl = σ-norbornenyl; NCO = quinoline-8-acyl; R = p-F-C6H4) (1) has been synthesized by the reaction of [Rh(nbd)Cl]2 (nbd = norbornadiene) with 2 equivalents of NCHO (quinoline-8-carbaldehyde) and 2 equivalents of PR3. Compound 1 has been fully characterized in solution and also in the solid state by X-ray diffraction. Compound 1 shows low stability in solution and undergoes slow ring closure isomerization to [RhCl(NCO)(ntyl)(PR3)] (ntyl = σ-nortricyclyl) (2) after 12 hours. Reaction of 1 with an extra equivalent of aldehyde (NCHO) and PR3 led to the formation of [RhCl(H)(NCO)(PR3)2] (3) and an equivalent of ketone, which is a hydroacylation product...
October 24, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Huining Chai, Qingfu Wang, Tingting Liu, Zhengkun Yu
Dinuclear ruthenium(ii)-NNN pincer complexes bearing a π linker-supported bis(pyrazolyl-imidazolyl-pyridine) ligand were synthesized and structurally characterized, and they exhibited excellent catalytic activity for the transfer hydrogenation of ketones in refluxing isopropanol, reaching TOF values up to 1.3 × 10(6) h(-1). Compared with the corresponding mononuclear Ru(ii)-NNN pincer complexes, the bimetallic complexes could be applied at concentrations as low as 0.03 mol% Ru and demonstrated remarkably enhanced catalytic activity in the transfer hydrogenation reactions of ketones...
October 24, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Juan F D Montero, Henrique A Tajiri, Guilherme M O Barra, Márcio C Fredel, Cesar A M Benfatti, Ricardo S Magini, Andréa L Pimenta, Júlio C M Souza
Poly(ether-ether-ketone) (PEEK) has also shown to be very attractive for incorporating therapeutic compounds thanks to a sulfonation process which modifies the material structure resulting in a sulfonated-PEEK (sPEEK). Concerning biomedical applications, the objective of this work was to evaluate the influence of different sulfonation degree of sPEEK on the biofilm growth. PEEK samples were functionalized by using sulphuric acid (98%) and then dissolved into dimethyl-sulfoxide. A dip coating technique was used to synthesize sPEEK thin films...
January 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Yun Ma, Russell F Algera, David B Collum
The reactivities and chemoselectivities of sodium diisopropylamide (NaDA) in N,N-dimethylethylamine (DMEA) are compared with those of lithium diisopropylamide (LDA) in tetrahydrofuran (THF). Metalations of arenes, epoxides, ketones, hydrazones, dienes, and alkyl and vinyl halides are represented. The positive attributes of NaDA-DMEA include high solubility, stability, resistance to solvent decomposition, and ease of preparation. The high reactivities and chemoselectivities often complement those of LDA-THF.
October 21, 2016: Journal of Organic Chemistry
N Fahrenfeld, A Pruden, M Widdowson
Methyl ethyl ketone (MEK) is a common groundwater contaminant often present with more toxic compounds of primary interest. Because of this, few studies have been performed to determine the effect of microbial community structure on MEK biodegradation rates in aquifer sediments. Here, microcosms were prepared with aquifer sediments containing MEK following a massive spill event and compared to laboratory-spiked sediments, with MEK biodegradation rates quantified under mixed aerobic/anaerobic conditions. Biodegradation was achieved in MEK-contaminated site sediment microcosms at about half of the solubility (356 mg/L) with largely Firmicutes population under iron-reducing conditions...
October 20, 2016: Biodegradation
Kosuke Murai, Keiichiro Tateishi, Akio Saito
Barluenga's reagent (IPy2BF4, Py = pyridine) treated with HBF4 efficiently catalyzes the inter- and intramolecular alkyne-carbonyl metathesis of unactivated alkynes with aldehydes or ketones, most of which proceed at room temperature. This work represents the first catalytic application of the Barluenga's reagent.
October 21, 2016: Organic & Biomolecular Chemistry
Song-Lin Zhang, Ze-Long Yu
Divergent synthesis of indoles, oxindoles, isocoumarins and isoquinolinones is described in this report by using a general Pd-catalyzed tandem reaction of β-hydroxy carbonyl compounds with aryl halides bearing an ortho-nitro, -ester or -cyano substituent. A key retro-aldol/α-arylation reaction is involved that merges classic Pd cross-coupling chemistry with novel Pd-promoted retro-aldol C-C activation to produce α-arylated ketones or esters. Subsequent intramolecular condensation of the carbonyl with the ortho-synthon gives target heterocycles...
October 21, 2016: Organic & Biomolecular Chemistry
A C Paulus, S Haßelt, V Jansson, A Giurea, H Neuhaus, T M Grupp, S Utzschneider
Introduction. Increasing interest developed in the use of carbon-fiber-reinforced-poly-ether-ether-ketones (CFR-PEEK) as an alternative bearing material in knee arthroplasty. The effects of CFR-PEEK wear in in vitro and animal studies are controversially discussed, as there are no data available concerning human tissue. The aim of this study was to analyze human tissue containing CFR-PEEK as well as UHMWPE wear debris. The authors hypothesized no difference between the used biomaterials. Methods and Materials...
2016: BioMed Research International
Ida Steen, Sandra S Waehrens, Mikael A Petersen, Morten Münchow, Wender L P Bredie
The present study aimed to investigate coffee flavour perception and release as function of serving temperature to support standardisation in the specialty coffee branch. The coffee cultivar Bourbon Caturra was evaluated at six serving temperatures ranging from 31°C to 62°C. Coffee samples were analysed by dynamic headspace sampling gas chromatography-mass spectrometry and descriptive analyses using sip-and-spit tasting. The release of volatiles followed mostly the van't Hoff principle and was exuberated at temperatures above 40°C...
March 15, 2017: Food Chemistry
Ramona Bosse Née Danz, Melanie Wirth, Annette Konstanz, Thomas Becker, Jochen Weiss, Monika Gibis
A simple, reliable and automated method was developed and optimized for qualification and quantification of aroma-relevant volatile marker compounds of North European raw ham using a headspace (HS)-Trap gas chromatography-mass spectrometry (GC-MS) and GC-flame ionization detector (FID) analysis. A total of 38 volatile compounds were detected with this HS-Trap GC-MS method amongst which the largest groups were ketones (12), alcohols (8), hydrocarbons (7), aldehydes (6) and esters (3). The HS-Trap GC-FID method was optimized for the parameters: thermostatting time and temperature, vial and desorption pressure, number of extraction cycles and salt addition...
March 15, 2017: Food Chemistry
S N Sruthi, M S Shyleshchandran, Sunil Paul Mathew, E V Ramasamy
The presence and distribution of a few organochlorine pesticides (OCPs) in the paddy fields of the Kuttanad agroecosystem (KAE) was examined in the present study. Kuttanad forms a part of the Vembanad wetland system which is a Ramsar site of international importance in the state of Kerala. This study, to the best of our knowledge, is the first report on the occurrence of OCP residues in KAE. Pesticide residue analysis was done with gas chromatograph (GC-ECD). Twenty-one soil samples were collected for the multiresidual analysis of OCPs...
October 20, 2016: Environmental Science and Pollution Research International
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