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https://www.readbyqxmd.com/read/28094363/photoassist-phosphorylated-tio2-as-a-catalyst-for-direct-formation-of-5-hydroxymethyl-furfural-from-glucose
#1
Masashi Hattori, Keigo Kamata, Michikazu Hara
Photo-assisted phosphorylation of an anatase TiO2 catalyst was examined to improve its catalytic performance for the direct production of 5-(hydroxymethyl)furfural (HMF), a versatile chemical platform, from glucose. In phosphorylation based on simple esterification between phosphoric acid and surface OH groups on anatase TiO2 with water-tolerant Lewis acid sites, the density of phosphates immobilized on TiO2 is limited to 2 phosphates nm(-2), which limits selective HMF production. Phosphorylation of the TiO2 surface under fluorescent light irradiation increases the surface phosphate density to 50%, which is higher than the conventional limit, thus preventing the adsorption of hydrophilic glucose molecules on TiO2 and resulting in a more selective HMF production over photoassist-phosphorylated TiO2...
January 17, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28069238/low-intensity-ultrasound-as-a-pretreatment-to-drying-of-daylilies-impact-on-enzyme-inactivation-color-changes-and-nutrition-quality-parameters
#2
Zhongyuan Zhang, Liying Niu, Dajing Li, Chunquan Liu, Rui Ma, Jiangfeng Song, Jiangtao Zhao
Effects of thermal and low intensity ultrasound combined with heat (LIUH) pretreatment prior to microwave vacuum drying on enzyme inactivation, color changes and nutrition quality properties of dried daylilies were investigated. The peroxidase (POD), ascorbic acid oxidase (AAO) and polyphenoloxidase (PPO) thermal and LIUH (0.2 and 0.4W/cm(2)) inactivation were determined and compared at 70, 80 and 90°C. Significant reduction in the POD, AAO and PPO activity was seen in daylilies after an ambient LIUH pretreatment than thermal pretreatment...
May 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28052535/synthesis-of-renewable-triketones-diketones-and-jet-fuel-range-cycloalkanes-with-5-hydroxymethylfurfural-and-ketones
#3
Shanshan Li, Fang Chen, Ning Li, Wentao Wang, Xueru Sheng, Aiqin Wang, Yu Cong, Xiaodong Wang, Tao Zhang
For the first time, a series of renewable C9-C12 triketones with repeating [COCH2CH2] units were synthesized in high carbon yields (~90%) by the aqueous phase hydrogenation of the aldol condensation products of 5-hydroxylmethylfurfural (HMF) and ketones over the Au/TiO2 catalyst. Compared with the reported routes, this new route has many advantages such as environmental friendly, fewer steps, using a cheaper easier separation and reusable catalyst, etc.. The triketones as obtained can be used as feedstocks in the production of conducting or semi-conducting polymers...
January 3, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28046627/tu-ab-202-11-tumor-segmentation-by-fusion-of-multi-tracer-pet-images-using-copula-based-statistical-methods
#4
J Lapuyade-Lahorgue, S Ruan, H Li, P Vera
PURPOSE: Multi-tracer PET imaging is getting more attention in radiotherapy by providing additional tumor volume information such as glucose and oxygenation. However, automatic PET-based tumor segmentation is still a very challenging problem. We propose a statistical fusion approach to joint segment the sub-area of tumors from the two tracers FDG and FMISO PET images. METHODS: Non-standardized Gamma distributions are convenient to model intensity distributions in PET...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28040870/innovative-methods-to-generate-clean-sugar-stream-from-biomass-feedstocks-for-efficient-fermentation
#5
REVIEW
Jung-Eun Lee, Yadhu N Guragain, Krishna P Bastola, Praveen V Vadlani
Sorghum stalks were evaluated to generate clean sugars; enzymatic hydrolysis efficiency of acid pretreated biomass was significantly low (12.3 g sugar/g pretreated biomass) compared to alkali method (49.1 g sugar/g pretreated biomass). Inhibitory compounds derived from acid pretreatment, such as hydroxymethyl furfural (HMF) and furfural, were effectively removed using an appropriate detoxification method using 1% (w/v) activated charcoal. The resin mixture containing cationic exchangers (DOWEX 50WX8) and anionic exchangers (IRA 743) in 7:3 ratio at pH 2...
December 31, 2016: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/28025633/childhood-hypopigmented-mycosis-fungoides-a-rare-diagnosis
#6
Cláudia Patraquim, Maria Miguel Gomes, Carla Garcez, Filipa Leite, Tereza Oliva, António Santos, Armando Pinto
Primary cutaneous lymphomas (PCL) are rare in pediatrics. Mycosis fungoides (MF) is the most frequent PCL diagnosed in childhood. There are various clinical variants of MF, including the hypopigmented MF (HMF). We present a 5-year-old boy with an 18-month history of progressive, generalized, nonpruritic hypopigmented lesions with central lacy erythema. He had no improvement with emollients. Skin biopsy showed typical features of HMF. He was treated with topical corticosteroids and tacrolimus and narrow-band ultraviolet B (NBUVB) phototherapy, with good response...
2016: Case Reports in Pediatrics
https://www.readbyqxmd.com/read/27995758/cellulose-biorefinery-based-on-combined-catalytic-and-biotechnological-approach-for-production-of-5-hmf-and-ethanol
#7
Ksenia N Sorokina, Oxana P Taran, Tatiana B Medvedeva, Yuliya V Samoylova, Alexandr V Piligaev, Valentin N Parmon
In this study, a combination of catalytic and biotechnological processes was proposed for the first time for application in a cellulose biorefinery for the production of 5-HMF and bioethanol. Hydrolytic dehydration of the mechanically activated microcrystalline cellulose over a carbon-based mesoporous Sibunt-4 catalyst resulted in moderate yields of glucose and 5-HMF (21.1-25.1% and 6.6-9.4%). 5-HMF was extracted from the resulting mixture with isobutanol and subjected to ethanol fermentation. A number of yeast strains were isolated that also revealed high thermotolerance (up to 50°C) and resistance to inhibitors found in the hydrolysates...
December 20, 2016: ChemSusChem
https://www.readbyqxmd.com/read/27987897/microwave-assisted-conversion-of-microcrystalline-cellulose-into-value-added-chemicals-using-dilute-acid-catalyst
#8
Teck Wei Ching, Victoria Haritos, Akshat Tanksale
One of the grand challenges of this century is to transition fuels and chemicals production derived from fossil feedstocks to renewable feedstocks such as cellulosic biomass. Here we describe fast microwave conversion of microcrystalline cellulose (MCC) in water, with dilute acid catalyst to produce valuable platform chemicals. Single 10min microwave assisted treatment was able to convert >60% of MCC, with >50mol% yield of desirable products such as glucose, HMF, furfural and levulinic acid. Recycling of residual MCC with make-up fresh MCC resulted in an overall conversion of >93% after 5 cycles while maintaining >60% conversion in each cycle...
February 10, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/27966286/biocatalytic-reduction-of-hmf-to-2-5-bis-hydroxymethyl-furan-by-hmf-tolerant-whole-cells
#9
Yan-Mei Li, Xue-Ying Zhang, Ning Li, Pei Xu, Wen-Yong Lou, Min-Hua Zong
Catalytic upgrading of 5-hydroxymethylfurfural (HMF), an important biobased platform chemical for high-value products, is currently of great interest. In this work, a new highly HMFtolerant yeast strain-Meyerozyma guilliermondii SC1103 was isolated, and biocatalytic reduction of HMF to 2,5-bis(hydroxymethyl)furan (BHMF) using its resting cells was reported. Cosubstrates exerted a significant effect on the catalytic activity and selectivity of microbial cells as well as their HMF-tolerant levels whereas the nitrogen source and mineral salts had no effects...
December 14, 2016: ChemSusChem
https://www.readbyqxmd.com/read/27937123/metabolic-engineering-of-saccharomyces-cerevisiae-for-improvement-in-stresses-tolerance
#10
Nileema R Divate, Gen-Hung Chen, Rupesh D Divate, Bor-Rung Ou, Yun-Chin Chung
Lignocellulosic biomass is an attractive low-cost feedstock for bioethanol production. During bioethanol production, Saccharomyces cerevisiae, the common used starter, faces several environmental stresses such as aldehydes, glucose, ethanol, high temperature, acid, alkaline and osmotic pressure. The aim of this study was to construct a genetic recombinant S. cerevisiae starter with high tolerance against various environmental stresses. Trehalose-6-phosphate synthase gene (tps1) and aldehyde reductase gene (ari1) were co-overexpressed in nth1 (coded for neutral trehalase gene, trehalose degrading enzyme) deleted S...
December 12, 2016: Bioengineered
https://www.readbyqxmd.com/read/27925403/heterogeneously-catalyzed-aerobic-oxidation-of-5-hydroxymethylfurfural-to-2-5-furandicarboxylic-acid-with-manganese-dioxide
#11
Eri Hayashi, Tasuku Komanoya, Keigo Kamata, Michikazu Hara
A simple non-precious metal catalyst system based on cost-effective and ubiquitously available MnO2, NaHCO3, and molecular oxygen was used to convert 5-hydroxymethylfurfural to 2,5-difurandicarboxylic acid as a bioplastics precursor in 91% yield. The MnO2 catalyst could be recovered by simple filtration and reused several times. The present system was also applicable to the aerobic oxidation of other biomass-derived substrates and the gram-scale oxidation of HMF to FDCA, in which 2.36 g (86% yield) of the analytically pure FDCA could be isolated...
December 7, 2016: ChemSusChem
https://www.readbyqxmd.com/read/27922695/effects-of-five-candidate-laxatives-derived-from-liriope-platyphylla-on-the-5-ht-receptor-signaling-pathway-in-three-cell-types-present-in-the-transverse-colon
#12
Ji Eun Kim, Eun Kyoung Koh, Sung Hwa Song, Ji Eun Sung, Hyun Ah Lee, Hong Gu Lee, Young Whan Choi, Dae Youn Hwang
The laxative effects of aqueous extract of Liriope platyphylla (AEtLP) on loperamide (Lop)‑induced constipation have been reported; however, the key compounds and the mechanism underlying these effects remain unclear. Therefore, the laxative effects of five candidates derived from L. platyphylla: Diosgenin (DG), 5-hydroxymethylfurfural (5-HMF), adenosine (AD), hydroxypropyl cellulose (HPC) and uridine (UD) were investigated by examining the alteration of G protein α (Gα) expression, protein kinase C (PKC) phosphorylation and inositol triphosphate (IP3) concentration levels in the 5-hydroxytryptamine (5‑HT; serotonin) receptor signaling pathway...
January 2017: Molecular Medicine Reports
https://www.readbyqxmd.com/read/27913172/efficient-catalytic-system-for-the-direct-transformation-of-lignocellulosic-biomass-to-furfural-and-5-hydroxymethylfurfural
#13
Luxin Zhang, Guoyun Xi, Jiaxin Zhang, Hongbing Yu, Xiaochang Wang
A feasible approach was developed for the co-production of 5-hydroxymethylfurfural (5-HMF) and furfural from corncob via a new porous polytriphenylamine-SO3H (SPTPA) solid acid catalyst in lactone solvents. XRD, SEM, XPS, N2 adsorption-desorption, elemental analysis, TG-DTA, acid-base titration and FTIR spectroscopy techniques were used to characterize the catalyst. This study demonstrates and optimizes the catalytic performance of SPTPA and solvent selection. SPTPA was found to exhibit superior catalytic ability in γ-valerolactone (GVL)...
January 2017: Bioresource Technology
https://www.readbyqxmd.com/read/27882693/direct-transformation-of-hmf-into-2-5-diformylfuran-and-2-5-dihydroxymethylfuran-without-an-external-oxidant-or-reductant
#14
Gang Li, Zhen Sun, Yueer Yan, Yahong Zhang, Yi Tang
The selective transformation of 5-hydroxymethylfurfural (HMF) to valuable 2,5-diformylfuran (DFF) and 2,5-dihydroxymethylfuran (DHMF) is highly desirable but remains a great challenge owing to its tendency to over-oxidation and over-reduction. In this work, HMF is directly converted into DFF and DHMF without external oxidant or reductant through a Meerwein-Ponndorf-Verley-Oppenauer (MPVO) reaction. In such a MPVO process, HMF is used as both oxidant and reductant and DFF and DHMF are simultaneously produced with a 1:1 molar ratio in the presence of a Lewis acid catalyst...
November 24, 2016: ChemSusChem
https://www.readbyqxmd.com/read/27873116/high-added-value-products-from-the-hydrothermal-carbonisation-of-olive-stones
#15
A M Borrero-López, V Fierro, A Jeder, A Ouederni, E Masson, A Celzard
Olive stones (OS) were submitted to hydrothermal carbonisation (HTC) in order to evaluate the possibility of producing high added-value products, mainly furfural (FU) and 5-hydroxymethylfurfural (5-HMF) on one hand and hydrochars and carbons on the other hand. Temperature (160-240 °C), residence time (1-8 h), initial pH (1-5.5) and liquid/solid ratio (4-48 w/w) were systematically varied in order to study the main products and to optimise FU production. FU production yield up to 19.9 %, based on the hemicellulose content, was obtained...
November 21, 2016: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/27863100/kinetics-of-levoglucosenone-isomerization
#16
Siddarth H Krishna, Theodore W Walker, James A Dumesic, George W Huber
We studied the acid-catalyzed isomerization of levoglucosenone (LGO) to 5-hydroxymethylfurfural (HMF) and developed a reaction kinetics model that describes the experimental data across a range of conditions (100-150 °C, 50-100 mm H2 SO4 , 50-150 mm LGO). LGO and its hydrated derivative exist in equilibrium under these reaction conditions. Thermal and catalytic degradation of HMF are the major sources of carbon loss. Within the range of conditions studied, higher temperatures and shorter reaction times favor the production of HMF...
November 15, 2016: ChemSusChem
https://www.readbyqxmd.com/read/27855921/determination-of-5-hydroxymethylfurfural-in-honey-using-headspace-solid-phase-microextraction-coupled-with-a-polyoxometalate-coated-piezoelectric-quartz-crystal
#17
Marta I S Veríssimo, José A F Gamelas, Dmitry V Evtuguin, M Teresa S R Gomes
High concentrations of 5-hydroxymethylfurfural (HMF) in honey provide an indication of overheating under inappropriate storage conditions or aging. Conventional methods for determining HMF are cumbersome and require expensive equipment or hazardous reagents. Hence the aim of this study was to propose a new analytical tool for HMF determination in honey, using a low cost acoustic wave sensor. Volatile organic compounds (VOCs) of honey samples were extracted, using the solid phase microextraction (SPME) technique, and HMF was quantified, using a piezoelectric quartz crystal with gold electrodes coated with a layer of decamolybdodivanado phosphoric acid, sensitive to HMF...
April 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27855905/bioactive-compounds-and-antioxidant-potential-in-tomato-pastes-as-affected-by-hot-and-cold-break-process
#18
Hasim Kelebek, Serkan Selli, Pınar Kadiroğlu, Osman Kola, Songul Kesen, Burçak Uçar, Başak Çetiner
The effects of hot and cold break industrial tomato paste production steps on phenolic compounds, carotenoids, organic acids, hydroxy methyl furfural (HMF) and other quality parameters of tomato pastes were investigated in this study. Phenolic compounds, carotenoids, organic acids, and HMF analyses were performed with LC-DAD-ESI-MS/MS and LC-DAD-RID was used for the sugar analyses. Furthermore, the antioxidant capacities of tomato pastes were assessed via the DPPH and ABTS methods. The increase of phenol acids at the processing steps of cold break production method was higher than the hot break production method...
April 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27847814/isoprene-production-on-enzymatic-hydrolysate-of-peanut-hull-using-different-pretreatment-methods
#19
Sumeng Wang, Ruichao Li, Xiaohua Yi, Tigao Fang, Jianming Yang, Hyeun-Jong Bae
The present study is about the use of peanut hull for isoprene production. In this study, two pretreatment methods, hydrogen peroxide-acetic acid (HPAC) and popping, were employed prior to enzymatic hydrolysis, which could destroy the lignocellulosic structure and accordingly improve the efficiency of enzymatic hydrolysis. It is proven that the isoprene production on enzymatic hydrolysate with HPAC pretreatment is about 1.9-fold higher than that of popping pretreatment. Moreover, through High Performance Liquid Chromatography (HPLC) analysis, the amount and category of inhibitors such as formic acid, acetic acid, and HMF were assayed and were varied in different enzymatic hydrolysates, which may be the reason leading to a decrease in isoprene production during fermentation...
2016: BioMed Research International
https://www.readbyqxmd.com/read/27837188/capsular-stroke-modeling-based-on-somatotopic-mapping-of-motor-fibers
#20
Hanlim Song, Wonbin Jung, Eulgi Lee, Ji-Young Park, Min Sun Kim, Min-Cheol Lee, Hyoung-Ihl Kim
Recently, several capsular stroke models have been reported with different targets of destruction. This study was performed to establish an accurate internal capsule (IC) target for capsular stroke modeling in rats. We injected adeno-associated virus serotype 5 (AAV)-CaMKII-EYFP into forelimb motor cortex and AAV-CaMKII-mCherry into hindlimb motor cortex (n = 9) to anterogradely trace the pyramidal fibers and map their somatotopic distribution in the IC. On the basis of the neural tracing results, we created photothrombotic infarct lesions in rat forelimb and hindlimb motor fiber (FMF and HMF) areas of the IC (n = 29) and assessed motor behavior using a forelimb-use asymmetry test, a foot-fault test, and a single-pellet reaching test...
November 11, 2016: Journal of Cerebral Blood Flow and Metabolism
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