Production and applications of carbohydrate-derived sugar acids as generic biobased chemicals

Abstract

This review considers the chemical and biotechnological synthesis of acids that are obtained by direct oxidation of mono- or oligosaccharide, referred to as sugar acids. It focuses on sugar acids which can be readily derived from plant biomass sources and their current and future applications. The three main classes of sugar acids are aldonic, aldaric and uronic acids. Interest in organic acids derived from sugars has recently increased, as part of the interest to develop biorefineries which produce not only biofuels, but also chemicals to replace those currently derived from petroleum. More than half of the most desirable biologically produced platform chemicals are organic acids. Currently, the only sugar acid with high commercial production is d-gluconic acid. However, other sugar acids such as d-glucaric and meso-galactaric acids are being produced at a lower scale. The sugar acids have application as sequestering agents and binders, corrosion inhibitors, biodegradable chelators for pharmaceuticals and pH regulators. There is also considerable interest in the use of these molecules in the production of synthetic polymers, including polyamides, polyesters and hydrogels. Further development of these sugar acids will lead to higher volume production of the appropriate sugar acids and will help support the next generation of biorefineries.

Catalytic Transformation of Biomass Derivatives to Value‐Added Chemicals and Fuels in Continuous Flow Microreactors

“…[60] The dehydration of sorbitol produces isosorbide, a building block for the production of fuels, solvents, plasticizers and pharmaceutical compounds. [63] Glucose can be isomerized to other C 6 -sugar configurations (e. g., fructose). Gluconic acid is used as an additive in food, pharmaceutical, paper and concrete industries.…”

Production of pectinases by solid-state fermentation of a mixture of citrus waste and sugarcane bagasse in a pilot-scale packed-bed bioreactor

“…Currently, citrus pulp is either dumped, or given away or sold with a very small margin to be used as a complement for cattle feed [2]. However, citrus waste biorefineries could be established to produce pectin [3], limonene [3][4][5], ethanol [3][4][5] and d-galacturonic acid as a platform chemical [6,7].…”

Sustainable Galactarate‐Based Polymers: Multi‐Enzymatic Production of Pectin‐Derived Polyesters

“…For each kilogram of sugar produced from sugar beet, ≈0.85 kg of Sugar Beet Pulp (SBP) is produced after sucrose extraction. Pectins, particularly the ones extracted from SBP, are rich in C6 sugar acids (uronic acids, UA) that can be converted to aldonic or aldaric acids (AA) using biochemical routes, or to 2,5‐furan dicarboxylic acid (FDCA) esters avoiding the unstable intermediate 5‐hydroxymethylfurfural (HMF) . Although they have a range of potential applications, UAs have not been exhaustively exploited as platform molecules for the synthesis of high added‐value products due to their high market price.…”