Carbohydrates biomass

Regarding the total amount of assimilated biomass, carbohydrates/polysaccha-rides represent the dominant class with an estimated amount of 1-4 X 10" tons of dry matter produced by photosynthesis annually ... 

Biomass, carbohydrates and, 973 Biosynthesis, fatty acids, 1138-1143 Biot, Jean Baptiste, 295 Biotin, fatty acid biosynthesis and, 1141... 

Heterogeneous catalysts, particularly zeolites, have been found suitable for performing transformations of biomass carbohydrates for the production of fine and specialty chemicals.123 From these catalytic routes, the hydrolysis of abundant biomass saccharides, such as cellulose or sucrose, is of particular interest. The latter disaccharide constitutes one of the main renewable raw materials employed for the production of biobased products, notably food additives and pharmaceuticals.124 Hydrolysis of sucrose leads to a 1 1 mixture of glucose and fructose, termed invert sugar and, depending on the reaction conditions, the subsequent formation of 5-hydroxymethylfurfural (HMF) as a by-product resulting from dehydration of fructose. HMF is a versatile intermediate used in industry, and can be derivatized to yield a number of polymerizable furanoid monomers. In particular, HMF has been used in the manufacture of special phenolic resins.125... 

Biomass carbohydrates, which represent the most abundant renewable sources available, are currently viewed as a feedstock for the green chemistry of the future [267-269]. 

Major biotechnological uses of the biomass carbohydrate moiety have attracted worldwide attention. Controlled cellulose degradation by cellulases may produce materials for important multifarious applications carbohydrates that can be used in the food and beverage industries, cellulose microfibril fragments for non-caloric food additives, hyperabsorbent cellulose fibers from fragmented cellulose microfibrils which can be used in biomedical, commercial and house-hold absorbent materials. Biomass-derived glucose syrups can also be used as carbon source in industrial fermentations for the production of antibiotics, industrial enzymes, amino-acids, and bulk chemicals. 

The reaction appears to be well suited for selective conversion of biomass carbohydrates into their corresponding oxidized derivatives. This system serves to oxidize several polymeric carbohydrates including starches and pullulan.445 49 More recent work has described the TEMPO-catalyzed introduction of carboxyl groups in native cellulose and its different morphological forms,45(M52 cellulose derivatives,453 and the surface of cellulose nanocrystals.454 The related biopolymer, chitin, also is oxidized under these conditions.455... 

The Embden-Meyerhof pathway via pyruvic acid is the normal route to fermentation products from biomass carbohydrates (Chapter 11). Enteric bacteria appear to have the unique capability of converting pyruvic acid directly to formic acid (Section I1,D) ... 

Various pulping technologies for wood and other biomass have been used for centuries to produce fiber, primarily for paper production. These processes effecbvely separate and clean the cellulose for use as fiber. However, the hemicellulose and lignin byproducts are not typically used for chemical products. The depolymerized hemicellulose in pulping liquor is a large source of biomass carbohydrate that could potentially be used for chemical producbon. 

Lactic acid is thus a perfectly suited chemical target to produce from biomass carbohydrates and no petrochemical routes for its formation are likely to take over. Once a proper chemical target molecule is selected, a fundamental understanding of the reaction network is crucial in order to tackle its selective formation from... 

Biotechnology continues to be an important contributor to the biorefinery, especially for the conversion of carbohydrates. The paper by Richard describes a new approach for the fermentation of C sugars, providing methodology for more efficient conversion of biomass carbohydrates to EtOH. The contribution from Nakas discusses the bioproduction of polyhydroxyalkanoates using levulinic acid as a carbon source. Stipanovic describes new approaches for using hemicellulose as a chemical feedstock. 

Our research has established a clean fractionation of biomass carbohydrate polymers into monomeric polyols which serve as a new alternative sugar platform. Polyols are obtained from biomass by chemical means, rather than by enzymatic degradation, and are further transformed by chemical means into quality fuels and other chemicals. 

Brinchi, L., Cotana, F., Fortunati, E., and Kenny, J. M. (2013). Production of nanociystalline cellulose from lignocellulosic biomass, Carbohydr. Polym, 94,154-169. 

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