A convenient system for producing 5-hydroxymethylfurfural (HMF) through dehydration of carbohydrates by microwave heating in the presence of ZnCl2 was studied. The use of ZnCl2 gave higher selectivity than other metal salts in the conversion of glucose. With ZnCl2 as catalyst, sucrose could be utilized effectively. Under the conditions of microwave irradiation (300 W, 8 min), HMF yields were 54...

5-hydroxymethylfurfural (5-hmf) is known as an indicator of quality deterioration in a wide range of foods. the current study covered 70 samples taken from domestically produced foods and drinks available on the iranian markets (including honey, jam, fruit cakes tomato paste, ketchup, syrup, fruit juice, canned fruit, uht milk, instant coffee and jelly powder). hmf levels were determined using ...

the conversion of the cellulose into 5-hmf would experience three steps, cellulose to glycose, glycose to fructose and fructose to 5-hmf. chloride ion can break down the hydrogen bond in cellucose, chromium can catalyze the isomerization of glycose to fructose, and the high temperature is helpful to cyclohydration of fructose to 5-hmf. in this paper, the sawdust has been directly degraded into ...

The one-pot acid-catalysed conversion of mono/di/polysaccharides (inulin, xylan, cellobiose, sucrose, glucose, fructose, xylose) into 2-furfuraldehyde (FUR) or 5-hydroxymethylfurfural (HMF) in the presence of aluminium-containing mesoporous TUD-1 (denoted as Al-TUD-1, Si/Al = 21), at 170 degrees C was investigated. Xylose gave 60% FUR yield after 6 h reaction; hexose-based mono/disaccharides ga...

The presence in orange juice of compounds that specifically inhibit the P-glycoprotein (P-gp) drug efflux transporter, but not the cytochrome P450 (CYP) isozyme CYP3A4, was investigated. The uptake of [(3)H]vinblastine, a substrate of P-gp, by Caco-2 cells was measured. An ethyl acetate extract of orange juice did not affect the initial uptake rate of [(3)H]vinblastine but significantly increas...

This work has established the optimum reaction conditions in a biphasic system using microcrystalline cellulose as the raw material, an ionic liquid as the solvent, metal chloride as a catalyst, and an organic solvent as the extraction reagent. The optimum reaction conditions were microcrystalline cellulose:ionic liquid 1:10 (mass ratio), chromium(III) chloride (CrCl3) 6.8 mol% (based on the gl...

We found an effective catalytic consortium capable of converting glucose to 5-hydroxymethylfurfural (HMF) in high yields (50%). The reaction consists a Lewis acid (NbCl5) and Brønsted (p-sulfonic calix[4]arene (CX4SO3H)), microwave-assisted reactor biphasic system. best result for the conversion HMF (yield 50%) was obtained with CX4SO3H/NbCl5 (5 wt%/7.5 wt%), using water/NaCl MIBK (1:3), at 150...

5-Hydroxymethylfurfural (HMF) is a versatile intermediate in biomass conversion pathways. However, the notoriously unstable nature of HMF imposes challenges to design selective routes to chemicals such as furan-2,5-dicarboxylic acid (FDCA). Here, a new strategy for obtaining furans is presented, bypassing the formation of the unstable HMF. Instead of starting with glucose/fructose and thus form...

HPLC methods are described for the determination of furanic compounds (hydroxymethylfurfural and furfural) in enteral formulas prepared with dextrinomaltose and milk proteins, and in model systems enclosing these ingredients. These compounds were extracted in aqueous solution, purified with organic solvents, and separated in a reversed-phase C18 column with water-acetonitrile (95:5 v/v). Averag...