Biomass biocatalytic conversion

Advantages of Genencor s biocatalytic conversion of biomass to value-added chemicals include, a) commercial viability, simplicity and economic feasibility b) prevention of product inhibition of cellulosic enzymes by concurrent conversion to bioproducts c) feasibility of quantitative conversion, d) elimination of byproducts e) higher productivity and yield on carbon J) production capacity enhancement. This biocatal) ic conversion concept is novel because a multienzyme process for converting renewable biomass to value-added commercial ingredients has not yet been commercially demonstrated. 

Ciftci, O. N., and F. Temelli. 2013. Continuous Biocatalytic Conversion of the Oil of Com Distiller s Dried Grains with Solubles to Fatty Acid Methyl Esters in Supercritical Carbon Dioxide. Biomass and Bioenergy 54 (0) 140-146. 

The harvested fermentation broth is treated to remove biomass and colored compounds before the cephalosporin C is converted into 7-amino-cephalosporanic acid (7-ACA) by a two-stage biocatalytic conversion [33]. 

Renewable raw materials can contribute to the sustainability of chemical products in two ways (i) by developing greener, biomass-derived products which replace existing oil-based products, e.g. a biodegradable plastic, and (ii) greener processes for the manufacture of existing chemicals from biomass instead of from fossil feedstocks. These conversion processes should, of course, be catalytic in order to maximize atom efficiencies and minimize waste (E factors) but they could be chemo- or biocatalytic, e.g. fermentation [3-5]. Even the chemocatalysts themselves can be derived from biomass, e.g. expanded com starches modified with surface S03H or amine moieties can be used as recyclable solid acid or base catalysts, respectively [6]. 

Genencor s proprietary concept of continuous biocatalytic systems using sequential enzyme reactions for processing the cellulosic component of biomass to biochemicals minimizes these problems. This concept addresses issues related to i) substrate inhibition, ii) enzyme inactivation, Hi) cofactor instability, iv) intermediate inhibition, and v) mass transfer limitations and thus overcomes key existing limitations for biomass conversion to industrial chemicals. ... 

Key advantages of this simple and economical in-vitro biocatalytic process for biomass conversion to gluconate are a) prevention of product inhibition of cellulosic enzymes by concurrent conversion to gluconate, b) feasibility of quantitative conversion c) elimination of byproduct formation, d) higher productivity, e) increased production capacity, and f) higher yield on carbon. 

A biocatalytic system for converting biomass to industrial chemicals is not only applicable to enzymatic conversions but also to fermentative conversion using cellulose. We report here three examples of fermentative conversion of cellulose to chemicals namely 1,3 propanediol, lactic acid, and succinic acid. 

This chapter is an overview of architectures adopted for the catalytic/biocatalytic composites used in wide applications like the biomass valorization or fine chemical industry. On this perspective, the chapter updates the reader with the most fresh examples of construction designs and concepts considered for the synthesis of such composites. Their catalytic properties result from the introduction of catalytic functionalities and vary from inorganic metal species e.g., Ru, Ir, Pd, or Rh) to well-organized biochemical structures like enzymes e.g., lipase, peroxidase, (3-galactosidase) or whole cells. Catalytic/biocatalytic procedures for the biomass conversion into platform molecules e.g., glucose, GVL, Me-THF, sorbitol, succinic acid, and glycerol) and their further transformation into value-added products are detailed in order to make understandable the utility of these complex architectures and to associate the composite properties to their performances, versatility, and robustness. 

Not the least, catalytic/biocatalytic systems can be very simple separated and recycled by applying an external magnetic force, avoiding the complications associated with the use of rmit operations as catalyst filtration or centrifugation. Hence, several designs of the magnetical-separated com-posite/biocomposite have been developed and appHed for biomass conversion into platform molecule and further to value-added products. 

Despite the previously mentioned examples vhich clearly prove the synthetic value of BY, there are several drawbacks that limit its vhdespread application to preparative organic chemistry (i) very low substrate concentrations tolerated by the microorganism that lead to an intrinsically too low productivity (ii) difficult work-up, due to the troublesome separation of the product from a huge amount of biomass (iii) typically incomplete conversion and occurrence of side reactions that imply the use of industrially unappealing chromatographic steps (iv) presence of enzymes with the same specific biocatalytic activity that might have different enantioselectivity. 

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