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https://www.readbyqxmd.com/read/28651356/heterologous-expression-in-pichia-pastoris-and-biochemical-characterization-of-the-unmodified-sulfatase-from-fusarium-proliferatum-le1
#1
Svetlana A Korban, Kirill S Bobrov, Maria A Maynskova, Stanislav N Naryzhny, Olga L Vlasova, Elena V Eneyskaya, Anna A Kulmisnkaya
Sulfatases are a family of enzymes (sulfuric ester hydrolases, EC 3.1.6.-) that catalyze the hydrolysis of a wide array of sulfate esters. To date, despite the discovery of many sulfatase genes and the accumulation of data on numerous sulfated molecules, the number of characterized enzymes that are key players in sulfur metabolism remains extremely limited. While mammalian sulfatases are well studied due to their involvement in a wide range of normal and pathological biological processes, lower eukaryotic sulfatases, especially fungal sulfatases, have not been thoroughly investigated at the biochemical and structural level...
June 23, 2017: Protein Engineering, Design & Selection: PEDS
https://www.readbyqxmd.com/read/28651324/preparation-of-activated-carbon-from-molasses-to-ethanol-process-waste-vinasse-and-its-performance-as-adsorbent-material
#2
Omer Kazak, Yasin Ramazan Eker, Haluk Bingol, Ali Tor
Herein, the preparation of activated carbon from waste vinasse by using hydrothermal H2O2 oxidation combined with a two-step pyrolysis process has been described for the first time as a new utilization approach for the waste vinasse. The characterization studies were performed by TGA, FT-IR, Raman spectroscopy, SEM-EDX and gas adsorption measurements. The approach generated a microporous activated carbon with high specific surface area (989m(2)/g) from waste vinasse. After simple experiments on various dye solutions, adsorption performance of the activated carbon was specifically studied on the methylene blue solution as functions of solution pH, contact time, adsorbent amount and reusability...
June 13, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28651315/linking-potential-nitrification-rates-nitrogen-cycling-genes-and-soil-properties-after-remediating-the-agricultural-soil-contaminated-with-heavy-metal-and-fungicide
#3
Manyun Zhang, Shahla Hosseini Bai, Li Tang, Yaling Zhang, Ying Teng, Zhihong Xu
Apart from the contaminant removal, the remediation of agricultural soil should also pay more attention to soil nutrient retention and biogeochemical cycling. This study aimed to evaluate changes of soil properties, potential nitrification rates (PNRs), and functional gene abundances and link their relationships after remediating co-contaminated agricultural soil with Medicago sativa L. (alfalfa) planting, alone or together with biochar application. Compared with the control (CK), alfalfa planting, alone or together with biochar application, could significantly increase soil organic matter (SOM) contents and discrepantly affect soil pH values...
June 19, 2017: Chemosphere
https://www.readbyqxmd.com/read/28651221/risk-element-immobilization-stabilization-potential-of-fungal-transformed-dry-olive-residue-and-arbuscular-mycorrhizal-fungi-application-in-contaminated-soils
#4
Mercedes García-Sánchez, Tereza Stejskalová, Inmaculada García-Romera, Jiřina Száková, Pavel Tlustoš
The use of biotransformed dry olive residue (DOR) as organic soil amendment has recently been proposed due to its high contents of stabilized organic matter and nutrients. The potential of biotransformed DOR to immobilize risk elements in contaminated soils might qualify DOR as a potential risk element stabilization agent for in situ soil reclamation practices. In this experiment, the mobility of risk elements in response to Penicillium chrysogenum-10-transformed DOR, Funalia floccosa-transformed DOR, Bjerkandera adusta-transformed DOR, and Chondrostereum purpureum-transformed DOR as well as arbuscular mycorrhizal fungi (AMF), Funneliformis mosseae, inoculation was investigated...
June 23, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28651082/impact-of-humic-acid-on-the-degradation-of-levofloxacin-by-aqueous-permanganate-kinetics-and-mechanism
#5
Ke Xu, Weiwei Ben, Wencui Ling, Yu Zhang, Jiuhui Qu, Zhimin Qiang
Levofloxacin (LF) is a frequently detected fluoroquinolone in surface water, and permanganate (MnO4(-)) is a commonly used oxidant in drinking water treatment. This study investigated the impact of humic acid (HA) on LF degradation by aqueous MnO4(-) from both kinetic and mechanistic aspects. In the absence of HA, the second-order rate constant (k) of LF degradation by MnO4(-) was determined to be 3.9 M(-1) s(-1) at pH 7.5, which increased with decreasing pH. In the presence of HA, the pseudo-first-order rate constant (kobs) of LF degradation at pH 7...
June 14, 2017: Water Research
https://www.readbyqxmd.com/read/28651081/inactivation-of-pathogenic-microorganisms-in-freshwater-using-hso5-uv-a-led-and-hso5-m-n-uv-a-led-oxidation-processes
#6
Jorge Rodríguez-Chueca, Tatiana Silva, José R Fernandes, Marco S Lucas, Gianluca Li Puma, José A Peres, Ana Sampaio
Freshwater disinfection using photolytic and catalytic activation of peroxymonosulphate (PMS) through PMS/UV-A LED and PMS/M(n+)/UV-A LED [M(n+) = Fe(2+) or Co(2+)] processes was evaluated through the inactivation of three different bacteria: Escherichia coli (Gram-negative), Bacillus mycoides (sporulated Gram-positive), Staphylococcus aureus (non-sporulated Gram-positive), and the fungus Candida albicans. Photolytic and catalytic activation of PMS were effective in the total inactivation of the bacteria using 0...
June 10, 2017: Water Research
https://www.readbyqxmd.com/read/28651072/understanding-the-quality-of-typical-and-atypical-dark-cutting-beef-from-heifers-and-steers
#7
S Mahmood, B C Roy, I L Larsen, J L Aalhus, W T Dixon, H L Bruce
Dark cutting beef with pH <6.0 may have glucidic potential approaching that of normal beef but has increased toughness that may also be influenced by cattle sex and carcass characteristics. Beef longissimus thoracis (LT) from normal (Canada AA; n=24), and typical (TB4; pH>5.9, n=20) and atypical (AB4; pH<5.9, n=20) dark cutting carcasses were analyzed to investigate relationships between beef quality, pH, glucidic potential and carcass characteristics. Results indicated that reduced lactate and glucidic potential were accompanied by increased pH and reduced L*, a* and b* values...
June 17, 2017: Meat Science
https://www.readbyqxmd.com/read/28651042/effect-of-dephytinization-by-fermentation-and-hydrothermal-autoclaving-treatments-on-the-antioxidant-activity-dietary-fiber-and-phenolic-content-of-oat-bran
#8
H Özkaya, B Özkaya, B Duman, S Turksoy
Fermentation and hydrothermal methods were tested to reduce the phytic acid (PA) content of oat bran and the effects of these methods on the dietary fiber (DF) and total phenolic (TP) contents and antioxidant activity (AA) were also investigated. Fermentation with 6% yeast and for 6 h resulted in 88.2% reduction in PA content while it was only 32.5% in sample incubated for 6 h without yeast addition. The PA loss in autoclaved oat bran sample (1.5 h, pH 4.0) was 95.2% while it was at most 41.8% in sample autoclaved without pH adjustment...
June 26, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28650660/ph-triggered-recovery-and-reuse-of-thiolated-poly-acryl-acid-functionalized-gold-nanoparticles-with-applications-in-colloidal-catalysis
#9
Siyam M Ansar, Benjamin D Fellows, Patrick Mispireta, O Thompson Mefford, Christopher L Kitchens
Thiolated poly(acrylic acid) (PAA-SH) functionalized gold nanoparticles were explored as a colloidal catalyst with potential application as a recoverable catalyst where the PAA provides pH-responsive dispersibility and phase transfer capability between aqueous and organic media. This system demonstrates complete nanoparticle recovery and redispersion over multiple reaction cycles without changes in nanoparticle morphology or reduction in conversion. The catalytic activity (rate constant) was reduced in subsequent reactions when recovery by aggregation was employed, despite unobservable changes in morphology or dispersability...
June 26, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28650655/vibrational-relaxation-of-the-backbone-and-bases-modes-in-lacdna-complexes-by-uv-resonance-raman-spectroscopy
#10
Cristina M Muntean, Ioan Bratu, Antonio Hernanz
Vibrational band shape analysis through time correlation function concept is widely used to obtain experimental information on the molecular dynamics of medium size molecules in different environments. Interesting details are revealed by extending this technique to biomolecules such as functional groups of the nucleic acids in media approaching the physiological conditions. In this work a study into the UV resonance Raman (UVRR) vibrational half bandwidths of functional groups in LacDNA, upon lowering the pH (pH 6...
June 26, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28650640/light-mediated-reactive-oxygen-species-generation-and-iron-redox-transformations-in-the-presence-of-exudate-from-the-cyanobacterium-microcystis-aeruginosa
#11
Kai Wang, Shikha Garg, T David Waite
The photochemical properties of the organic exudate secreted by a toxic strain of Microcystis aeruginosa were studied by measuring reactive oxygen species (ROS) generation and redox transformations of iron in the presence of the organic exudate under acidic (pH 4) and alkaline (pH 8) conditions. Our results show that the organic exudate generates nanomolar concentrations of superoxide and hydrogen peroxide on irradiation with simulated sunlight in a manner consistent with that reported for terrigenous natural organic matter...
June 26, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28650626/selenium-sequestration-in-a-cationic-layered-rare-earth-hydroxide-a-combined-batch-experiments-and-exafs-investigation
#12
Lin Zhu, Linjuan Zhang, Jie Li, Duo Zhang, Lanhua Chen, Daopeng Sheng, Shitong Yang, Chengliang Xiao, Jianqiang Wang, Zhifang Chai, Thomas E Albrecht-Schmitt, Shuao Wang
Selenium is of great concern owing to its acutely toxic characteristic at elevated dosage and the long-term radiotoxicity of 79Se. The contents of selenium in industrial wastewater, agricultural runoff, and drinking water have to be constrained to a value of 10 μg/L as the maximum concentration limit. We reported here the selenium uptake using a structurally well-defined cationic layered rare earth hydroxide, Y2(OH)5Cl•1.5H2O. The sorption kinetics, isotherms, selectivity, and desorption of selenite and selenate on Y2(OH)5Cl•1...
June 26, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28650621/novel-cdta-based-bifunctional-chelators-for-stable-and-inert-mn-ii-complexation-synthesis-and-physicochemical-characterization
#13
Christian Vanasschen, Enikő Molnár, Gyula Tircsó, Ferenc K Kálmán, Éva Tóth, Marie Brandt, Heinz H Coenen, Bernd Neumaier
In the search for Mn(II) MR and PET/MR imaging agents with optimal balance between thermodynamic stability, kinetic inertness, and relaxivity, two novel bifunctional Mn(II) chelators (BFMnCs) based on CDTA (trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid) were synthesized. A six-step synthesis, involving the buildup of a functionalized trans-1,2-diaminocyclohexane core, provided CuAAC-reactive 6a and 6b bearing an alkyne or azide substituent on the cyclohexane ring, respectively (CuAAC = Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition)...
June 26, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28650571/development-of-proton-responsive-catalysts
#14
REVIEW
Lin Wang, Ryoichi Kanega, Hajime Kawanami, Yuichiro Himeda
A changeable ligand, which involves in activation of a catalyst or assists a reaction, draws an increasing attention, in contrast to a classical ligand as spectator. Proton-responsive catalysts, which are capable of undergoing changes of properties on gaining/losing one or more protons, provides interesting features as follows: (i) catalyst activation by electronic effect, (ii) pH-tuning of water-solubility, and (iii) second-coordination-sphere interaction. On the basis of this catalyst design concept, we developed several highly efficient proton-responsive catalysts for CO2 hydrogenation as H2 storage, formic acid (FA) dehydrogenation as H2 production, and transfer hydrogenation...
June 26, 2017: Chemical Record: An Official Publication of the Chemical Society of Japan ... [et Al.]
https://www.readbyqxmd.com/read/28650501/ph-responsive-near-infrared-fluorescent-cyanine-dyes-for-molecular-imaging-based-on-ph-sensing
#15
Koji Miki, Kentaro Kojima, Kazuaki Oride, Hiroshi Harada, Akiyo Morinibu, Kouichi Ohe
Indocyanine green (ICG) derivatives having nucleophilic substituents were synthesized as pH-responsive near-infrared dyes. pH-responsive dyes 1-C with closed-ring structures smoothly internalized and converted to emissive open-ring structures 1-O in response to relatively low pHs in acidic intracellular compartments of HeLa cells.
June 26, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28650333/simultaneous-determination-of-ace-inhibitors-and-dexibuprofen-in-active-pharmaceutical-ingredient-formulations-and-human-serum-by-rp-hplc
#16
Aisha Sana, Safila Naveed, Fatima Qamar, Sadia Shakeel
The contemporary work describes a rapid and cost effective reversed phase High Performance Liquid Chromatography (RP-HPLC) method for the quantification of Captopril, Lisinopril and Dexibuprofen (DXP) simultaneously in dosage formulations, active pharmaceutical ingredients and human serum. The chromatographic system included LC-20A pump, Sil-20A auto sampler and SPD-20A UV/visible detector. The estimation was carried out by using a C18 (5μm, 250 ×4.6 mm) column with mobile phase methanol: water (80:20 v/v, pH 3...
March 2017: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28650328/studies-on-self-nanoemulsifying-drug-delivery-system-of-flurbiprofen-employing-long-medium-and-short-chain-triglycerides
#17
Junaid Daar, Ahmad Khan, Jallat Khan, Amjad Khan, Gul Majid Khan
The aim of the study was to successfully design, formulate and evaluate self-nanoemulsifying drug delivery system (SNEDDS) of poorly aqueous soluble drug viz. flurbiprofen using long (LCT), medium (MCT) and short chain triglycerides (SCT). The SNEDDS are thermodynamically stable lipid based drug delivery systems which consist of mixture of oil, surfactant and co-surfactant. Upon aqueous dilution, this mixture produces nano-emulsion spontaneously on slight agitation. The excipients intended to be used were screened for their potential to dissolve the drug and to form clear dispersion upon aqueous dilution...
March 2017: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28650324/formulation-evaluation-and-release-rate-characteristics-of-medicated-jelly-of-vitamin-c
#18
Khalid A Ibrahim, Asma Nawaz, Shamim Mumtaz, Furqan Muhammad Iqbal, Ahmad Khan, Shahiquz Zaman, Nasser M Abd El-Salam, Naseem Ullah, Tajamul Husain, Syed Nisar Hussain Shah
Medicated jelly formulations are patient friendly dosage form for pediatric, geriatric and dysphagic patients. These formulations offer rapid dissolution and absorption of drugs through oral mucosa therefore show the early onset of action. The objective of the study was to develop and evaluate oral jelly formulations of vitamin C. Slurry method was adopted using glucose 103gm, sugar 67gm, gelatin 10gm and sorbitol 6.56gm. Preformulation studies were performed including the organoleptic profile, pH, and solubility of both drugs...
March 2017: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28650314/natrinema-soli-sp-nov-a-novel-halophilic-archaeon-isolated-from-a-hypersaline-wetland
#19
Mehrnoosh Rasooli, Ali Naghoni, Mohammad Ali Amoozegar, Leila Mirfeizi, Mahdi Moshtaghi Nikou, Seyed Abolhassan Shahzadeh Fazeli, Hiroaki Minegishi, Antonio Ventosa
An extremely halophilic archaeon, designated strain 5-3T, was isolated from a soil sample of Meighan wetland in Iran. Strain 5-3T was strictly aerobic, catalase-positive and oxidase-negative. Cells were Gram-stain-negative, non-motile and ovoid. Colonies of strain 5-3T were cream-coloured. The isolate showed optimum growth at 4.0 M NaCl, 40 °C and pH 7.0. The major polar lipids of the strain were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, two unknown phospholipids and three glycolipids (including one that was chromatographically identical to S2-DGD)...
June 26, 2017: International Journal of Systematic and Evolutionary Microbiology
https://www.readbyqxmd.com/read/28650149/rplc-hilic-and-sfc-with-mass-spectrometry-polarity-extended-organic-molecule-screening-in-environmental-water-samples
#20
Stefan Bieber, Giorgia Greco, Sylvia Grosse, Thomas Letzel
Trace organic compounds are important in environmental analysis, because they impact water quality and introduce potential (eco)toxicological effects. Current analytical methods mostly rely on gas chromatography (GC) or reversed-phase liquid chromatography (RPLC) coupled with (tandem) mass spectrometry. However, neither method can easily separate very polar molecules. This study presents, two chromatographic separation strategies, a serial RPLC- hydrophilic interaction liquid chromatography (RPLC-HILIC) coupling and an analytical scale supercritical fluid chromatography (SFC) system, and validates their separation effectiveness as polarity-extended chromatographic methods for 274 environmentally relevant compounds...
June 26, 2017: Analytical Chemistry
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