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https://www.readbyqxmd.com/read/27882693/direct-transformation-of-hmf-into-2-5-diformylfuran-and-2-5-dihydroxymethylfuran-without-an-external-oxidant-or-reductant
#1
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
#2
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
#3
Siddarth H Krishna, Theodore W Walker, James A Dumesic, George W Huber
We have studied the acid-catalyzed isomerization of levoglucosenone (LGO) to 5-hydroxymethylfurfural (HMF) and developed a reaction kinetics model which describes the experimental data across a range of conditions (100-150oC, 50-100 mM H2SO4, 50-150 mM LGO). LGO and its hydrated derivative exist in equilibrium at 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
#4
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
#5
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
#6
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
#7
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
https://www.readbyqxmd.com/read/27830360/efficient-utilization-of-eucheuma-denticulatum-hydrolysates-using-an-activated-carbon-adsorption-process-for-ethanol-production-in-a-5-l-fermentor
#8
Chae Hun Ra, Min Ji Kim, Gwi-Taek Jeong, Sung-Koo Kim
A total monosaccharide concentration of 37.8 g/L and 85.9% conversion from total fermentable monosaccharides of 44.0 g/L from 110 g dw/L Eucheuma denticulatum slurry were obtained by thermal acid hydrolysis and enzymatic saccharification. Subsequent adsorption treatment to remove 5-hydroxymethylfurfural (5-HMF) using 5% activated carbon and an adsorption time of 10 min were used to prevent a prolonged lag phase, reduced cell growth, and low ethanol production. The equilibrium adsorption capacity (q e) of HMF (58...
November 9, 2016: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/27829919/superelectrophilic-activation-of-5-hydroxymethylfurfural-and-2-5-diformylfuran-organic-synthesis-based-on-biomass-derived-products
#9
Dmitry S Ryabukhin, Dmitry N Zakusilo, Mikhail O Kompanets, Anton A Tarakanov, Irina A Boyarskaya, Tatiana O Artamonova, Mikhail A Khohodorkovskiy, Iosyp O Opeida, Aleksander V Vasilyev
The reaction of 5-hydroxymethylfurfural (5-HMF) with arenes in superacidic trifluoromethanesulfonic acid (triflic acid, TfOH) as the solvent at room temperature for 1-24 h gives rise to 5-arylmethylfurfurals (yields of 17-91%) and 2-arylmethyl-5-(diarylmethyl)furans (yields of 10-37%). The formation of these two types of reaction products depends on the nucleophilicity of the arene. The same reactions under the action of acidic zeolites H-USY in high pressure tubes at 130 °C for 1 h result in the formation of only 5-arylmethylfurfurals (yields of 45-79%)...
2016: Beilstein Journal of Organic Chemistry
https://www.readbyqxmd.com/read/27812888/5-hmf-attenuates-striatum-oxidative-damage-via-nrf2-are-signaling-pathway-following-transient-global-cerebral-ischemia
#10
Bai-Liu Ya, Hong-Fang Li, Hai-Ying Wang, Fei Wu, Qing Xin, Hong-Ju Cheng, Wen-Juan Li, Na Lin, Zai-Hua Ba, Ru-Juan Zhang, Qian Liu, Ya-Nan Li, Bo Bai, Feng Ge
Recent studies have shown 5-hydroxymethyl-2-furfural (5-HMF) has favorable biological effects, and its neuroprotection in a variety of neurological diseases has been noted. Our previous study showed that treatment of 5-HMF led to protection against permanent global cerebral ischemia. However, the underlying mechanisms in cerebral ischemic injury are not fully understood. This study was conducted to investigate the neuroprotective effect of 5-HMF and elucidate the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway mechanism in the striatum after transient global cerebral ischemia...
November 3, 2016: Cell Stress & Chaperones
https://www.readbyqxmd.com/read/27810249/microwave-assisted-chemical-pre-treatment-of-waste-sorghum-leaves-process-optimization-and-development-of-an-intelligent-model-for-determination-of-volatile-compound-fractions
#11
Daneal C S Rorke, Terence N Suinyuy, E B Gueguim Kana
This study reports the profiling of volatile compounds generated during microwave-assisted chemical pre-treatment of sorghum leaves. Compounds including acetic acid (0-186.26ng/g SL), furfural (0-240.80ng/g SL), 5-hydroxymethylfurfural (HMF) (0-19.20ng/g SL) and phenol (0-7.76ng/g SL) were detected. The reducing sugar production was optimized. An intelligent model based on Artificial Neural Networks (ANNs) was developed and validated to predict a profile of 21 volatile compounds under novel pre-treatment conditions...
October 22, 2016: Bioresource Technology
https://www.readbyqxmd.com/read/27806885/modeling-the-production-of-sugar-and-byproducts-from-acid-bisulfite-pretreatment-and-enzymatic-hydrolysis-of-douglas-fir
#12
Yalan Liu, Jinwu Wang, Michael Wolcott
The aim of this work was to investigate the kinetics of multiple chemicals in acid bisulfite pretreatment and the relationship between total sugar yields and pretreatment factors (temperature and time). The results showed Saeman model accurately fitted the pretreatment process. According to this kinetic model, a maximum hemicellulose hydrolysis yield was achieved at a treatment time of 75min with a temperature of 145°C. Meantime, the concentrations of acetic acid, hydroxymethylfurfural (HMF), and furfural were 1...
October 25, 2016: Bioresource Technology
https://www.readbyqxmd.com/read/27800655/relationship-between-hmf-intake-and-smf-formation-in-vivo-an-animal-and-human-study
#13
Silvia Pastoriza de la Cueva, Juana Álvarez, Ákos Végvári, Javier Montilla-Gómez, Olga Cruz-López, Cristina Delgado-Andrade, José A Rufián-Henares
SCOPE: 5-Hydroxymethylfurfural (HMF) is a furanic compound produced in heat-processed foods by non-enzymatic browning reactions. HMF has been demonstrated to be hepato- and nephrotoxic in animals with a link to its metabolite 5-sulfooxymethylfurfural (SMF). To date little is known about either the formation of SMF from ingested HMF, or the formation of DNA adducts in animals or human beings. METHODS AND RESULTS: To assess SMF in vivo formation, we first performed a study in mice treated with high/low doses of oral HMF...
November 1, 2016: Molecular Nutrition & Food Research
https://www.readbyqxmd.com/read/27798321/detection-of-5-hydroxymethylfurfural-and-furfural-in-the-aerosol-of-electronic-cigarettes
#14
Sarah Soussy, Ahmad El-Hellani, Rima Baalbaki, Rola Salman, Alan Shihadeh, Najat A Saliba
SIGNIFICANCE: The wide availability of sweet flavours has been hypothesised as a factor in the popularity of electronic cigarette (ECIG), especially among youth. Saccharides, which are commonly used to impart a sweet flavour to ECIG liquids, thermally degrade to produce toxic compounds, like aldehydes and furans. This study investigates the formation of furanic compounds in aerosols when ECIG liquid solutions of varying sweetener concentrations are vaped under different power and puff duration...
October 25, 2016: Tobacco Control
https://www.readbyqxmd.com/read/27795308/metabolic-engineering-of-raoultella-ornithinolytica-bf60-for-the-production-of-2-5-furandicarboxylic-acid-from-5-hydroxymethylfurfural
#15
Gazi Sakir Hossain, Haibo Yuan, Jianghua Li, Hyun-Dong Shin, Miao Wang, Guocheng Du, Jian Chen, Long Liu
: 2, 5-Furandicarboxylic acid (FDCA) is an important renewable biotechnological building block because it serves as an environmentally friendly substitute for terephthalic acid in the production of polyesters. Currently, FDCA is mainly produced via chemical oxidation, which can cause severe environmental pollution. In this study, we developed an environmentally friendly process for the production of FDCA from 5-hydroxymethyl furfural (5-HMF) using a newly isolated strain, Raoultella ornithinolytica BF60...
October 21, 2016: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/27784929/effect-of-freezing-and-room-temperatures-storage-for-18%C3%A2-months-on-quality-of-raw-rapeseed-honey-brassica-napus
#16
Monika Kędzierska-Matysek, Mariusz Florek, Anna Wolanciuk, Piotr Skałecki
The physicochemical properties, colour characteristics and dynamic viscosity of fresh rapeseed honey (control, CON) and those stored for 18 months at room temperature (RT) or in freezer (FRO) were compared. The significant decrease of pH after storage was found. Honey stored at RT showed an increase of 5-hydroxymethylfurfural (HMF) (+543.0 %) and decrease of diastase activity (-24.4 %), while in FRO samples the decreasing course (-50.5 and -7.3 %, p > 0.05) were found in comparison with CON samples (3...
August 2016: Journal of Food Science and Technology
https://www.readbyqxmd.com/read/27777448/implementing-principles-of-traditional-concentrated-grape-must-fermentation-to-the-production-of-new-generation-balsamic-vinegars-starter-selection-and-effectiveness
#17
Sofia Lalou, Angela Capece, Fani Th Mantzouridou, Patrizia Romano, Maria Z Tsimidou
In an effort to implement principles of traditional concentrated grape must fermentation to the production of new generation balsamic vinegars (BVs), the specific goals of the study were the isolation and molecular identification of the predominant yeasts in concentrated grape must (cv. Xinomavro), their technological characterization and the evaluation of the fermentative aptitude of the selected strains. Tolerance against 5-hydroxymethyl-furfural (HMF) and furfural, acetic acid and glucose concentration was examined by appropriate methods and tests...
September 2016: Journal of Food Science and Technology
https://www.readbyqxmd.com/read/27765979/the-effects-of-production-methods-and-storage-on-the-chemical-constituents-of-apple-pekmez
#18
Alper Kuşçu, Özcan Bulantekin
The purposes of this study were to investigate the effects of two different pekmez production methods namely open pan evaporation (OPE) and vacuum evaporation (VE) on the final products, and to observe the changes in constituents as well as aromatic components after 4 months of storage. The initial and poststorage (4 months) 5-hydroxymethyl furfural (HMF) content in OPE apple pekmez were respectively 5.48, and 7.04 mg/kg. No HMF was detected in VE apple pekmez. Both initial and poststorage content of phenolic compounds was higher in VE pekmez compared to OPE pekmez...
July 2016: Journal of Food Science and Technology
https://www.readbyqxmd.com/read/27765717/comparison-of-in%C3%A2-vivo-immunomodulatory-effects-of-5-hydroxymethylfurfural-and-5-5-oxydimethylenebis-2-furfural
#19
Ni Lin, Tiantian Liu, Lin Lin, Sheng Lin, Qingce Zang, Jiuming He, Zeper Abliz, Chao Li, Aiping Wang, Hongtao Jin
The standard of 5-Hydroxymethylfurfural (5-HMF) existed in dextrose injection as an inevitable by-product during high-temperature setrilization has been included in pharmacopoeias considering its hazardous effects on human health. We found that the concentrations of 5-HMF in some traditional Chinese medicine injections (TCMIs) far exceeded its limit in dextrose injection. Besides, we detected 5, 5'-Oxydimethylenebis (2-furfural) (OMBF) in those TCMIs containing high concentrations of 5-HMF. We investigated the in vivo immunomodulatory effects of 5-HMF and OMBF at three dose levels using the reporter antigen popliteal lymph node assay (RA-PLNA), which allows the straightforward examination and mechanistic study of immunotoxicity of low molecular weight compounds...
November 2016: Regulatory Toxicology and Pharmacology: RTP
https://www.readbyqxmd.com/read/27765239/evaluation-of-the-antioxidant-capacity-furan-compounds-and-cytoprotective-cytotoxic-effects-upon-caco-2-cells-of-commercial-colombian-coffee
#20
Daniel Bedoya-Ramírez, Antonio Cilla, José Contreras-Calderón, Amparo Alegría-Torán
Antioxidant capacity (AC), total phenolics (TPs), furan compounds (HMF and furfural F) and cytoprotective/cytotoxic effects upon Caco-2 cells (MTT, cell cycle and reactive oxygen species (ROS)) were evaluated in Colombian coffee (2 ground and 4 soluble samples). The AC (ABTS and FRAP), TPs and HMF ranged between 124-722, 95-802μmoles Trolox/g, 21-100mg gallic acid/g and 69-2900mg/kg, respectively. Pretreatment of cells for 24h with lyophilized coffee infusions at the highest dose without cytotoxic effects (500μg/mL) significantly prevented the decrease in cell viability compared to control stress with H2O2 (5mM/2h), recovering viability to values between 34% and 45% and restoring the control values without stress induction in the G1 phase of cell cycle...
March 15, 2017: Food Chemistry
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