Hydroxymethyl furfural HMF

Scheme 6 Fructose can be transformed into 5-hydroxymethyl furfural (HMF) via acid-catalyzed dehydration. Solid acid catalysts applied to facilitate the reaction are zeolites, ion-exchange resins and solid inorganic phosphates. With sporadic success, notably with inorganic phosphates, other carbohydrate sources such as inulin can also be transformed into HMF.

The fermentation inhibitors include furan aldehydes, aliphatic acids, and phenolic compounds. The furan aldehydes, furfural, and hydroxymethyl furfural (HMF), are formed from pentoses and hexoses, respectively (4,5). Several studies indicate that furfural inhibits Saccharomyces cerevisiae, at least when present in high concentrations (6-10). HMF has a similar effect (11,12). 

Table 7.2 Conversion and selectivity to 5-hydroxymethyl furfural (HMF) for dehydration of fructose and precursors over H-Mordenite (Si/AI — II) at 165 °C in water/methyl isobutyl ketone (1 5 by volume)...

Hot HCl converts fructose to hydroxymethyl furfural (HMF), which links with resorcinol to produce a red compound. To make the reagent, dissolve 50 mg of resorcinol in 33 mL of concentrated HCl and dilute to 100 mL with water. Add 0.5 mL of urine to 5mL of reagent in a test tube and bring to a boil. Fructose produces a red reaction within 30 seconds. The test is sensitive to 100 mg fructose per dL, provided there is no excess glucose. A 2-g/dL solution of glucose produces about the same color as 100 mg/dL of fructose after 30 seconds of boiling. A solution of fructose (0.5g/dL) should be used as a control. With high concentrations of fructose, a red precipitate forms. 

Figure 6. (A) Current-time traces for S. cerevisiae cells recorded upon titration with 5-hydroxymethyl furfural (HMF). (Reprinted with permission from Ref [9], 2009 American Chemical Society.) (B) Dose response curves based on Ai values in (A). (Lower panel a schematic presentation of the ADH6 catalyzed NADPH dependent reduction of HMF.)...

This chapter provides an industrial perspective on several oxidation routes to new bio-based molecules. In particular, it focuses on the use of Co/Mn/Br catalyst systems in air oxidations, based on the Amoco Mid-Century catalyst system used for / r -xylene oxidation (also see Chapter 4), as an efficient methodology for the conversion of 5-(hydroxymethyl)furfural (HMF) and 5-(methoxymethyl)furfural (MMF) to 2,5-furandicarboxylic acid (FDCA) in Avantium s YXY process. In addition, other less-studied conversions, such as methyl levulinate (ML) to succinic acid (SA), lignin to a variety of aromatic and phenolic carboxylic acids, are discussed as well. 

Degradation of the sucrose framework Reactions or reaction cascades, including dehydration/rehydration, ring opening/closure, bond scission/ formation lead to structures being of known value from petrochemically derived compounds, but are based on the renewable feedstock sucrose, the most prominent representatives being bioethanol and 5-hydroxymethyl furfural (HMF). 

Abstract The synthesis and chemistry of 5-(hydroxymethyl)furfural (HMF), 5-(chloromethyl)furfural (CMF), and levulinic acid (LA), three carbohydrate-derived platform molecules produced by the chemical-catalytic processing of lignocellulosic biomass, is reviewed. Starting from the historical derivation of these molecules and progressing through modem approaches to their production from biomass feedstocks, this review will then survey their principal derivative chemistries, with particular attention to aspects of commercial relevance, and discuss the relative merits of each molecule in the future of biorefining. 

Brasholz M, von Kanel K, Homung CH, Saubem S, Tsanaktsidis J (2011) Highly efficient dehydration of carbohydrates to 5-(chloromethyl)furfural (CMF), 5-(hydroxymethyl)furfural (HMF) and levulmic acid by biphasic continuous flow processing. Green Chem 13 1114-1117... 

The steps in the formation of 5-hydroxymethyl furfural (HMF) from 1,2-enediol is shown in Formula 4.37. HMF is also used as an indicator for the heating of carbohydrate containing food, e. g., honey. The (retro-Michael addition) water elimination at C-3 and subsequently at C-4 leads to a 1,2-diulose (3,4-dideoxyosone), which after cyclization to a hemiacetal, a dihy-drofuran, releases another molecule of water, producing HMF. In the same way, e. g., furfural can be made from pentoses and 5-methylfurfural from the 6-methylpentose rhamnose. 2-Hydroxyacetylfuran, which is preferentially formed from fructose, can be obtained starting from the corresponding 2,3-enediol by water elimination at C-4, followed by C-5 (Formula 4.38). 

Maillard reactions between lactose and amino groups (e. g. lysine) which, in a classical sterilization process, causes browning of milk and formation of hydroxymethyl furfural (HMF). 

When furfural and L-lysine are dissolved in 0.5 M acetate buffer (pH 5.0) and heated, the solution turned brown more intensively than the solution containing glucose and 5-hydroxymethyl furfural (HMF) with L-lysine. HMF is the major decomposition product of hexose under acidic conditions. Low molecular weight pigments in the heated solution containing furfural and L-lysine were examined by ODS-HPLC equipped with a photodiode-array detector (DAD). 

Abstract 2,5-Furandicarboxylic acid (FDCA) is considered a highly promising bio-based alternative to terephthalic acid for the production of polymers. Wholecell biotransformation of 5-(hydroxymethyl)furfural (HMF) into FDCA is catalyzed by the HMF/furfural oxidoreductase HmfH from Cupriavidus basilensis... 

Fig. 2 Putative subcellular localization of HMF oxidizing reactions in P. putida strains S12 HmfH (a), S12 B38 (b), and S12 B97 (c). ADH aldehyde dehydrogenase from either C. basilensis HMF14 (c) or native to P. putida S12 (p). HMF 5-(hydroxymethyl)furfural, HMF acid 5-(hydroxymethyl)furoic acid, FFA 5-formylfuroic acid, FDCA 2,5-furandicarboxylic acid...

To illustrate the use of LDA for food authentication, an example involving the classification of honey samples according to their floral origin will be used [15]. In particular, the data set comprises the results of 15 determinations— pH free, lactone, and total acidity diastase water content specific conductivity dextrose, fiructose and DP2 colour specific rotation hydroxymethyl-furfural (HMF) content and (on the whole sample and on the... 

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