Systems and methods of making lactobionic acid are described. The systems include two-compartment cation bipolar electrodialysis assemblies having at least one cell that includes a cation ion-exchange membrane and a bipolar membrane. The membranes define the borders of a pair of flow channels for a separate (i) caustic stream and (i) purified lactobionic acid stream. Lactobionate ions in the lactobionic acid stream do not cross a membrane in the electrodialysis assembly, which reduces membrane fouling. The methods include passing a lactobionate salt through a two-compartment cation bipolar electrodialysis assembly. The electrodialysis assembly includes at least one two-compartment cation bipolar membrane cell, and separates the lactobionate salt into a caustic compound and the lactobionic acid. The assembly is designed so the lactobionate ions do not cross an ion exchange membrane in the assembly to form the lactobionic acid, which reduces membrane fouling.

A hydrogen peroxide and gluconic acid production method and system is disclosed that can include receiving an aqueous solution having glucose, water, and glucose oxidase at a reaction chamber. Here, the reaction chamber facilitates an enzymatic reaction between a gas phase and a liquid phase of the aqueous solution, thereby yielding a first solution comprising hydrogen peroxide, gluconic acid, and the glucose oxidase. The method can further include receiving the first solution at a separation chamber, wherein the separation chamber is comprised of a semi-permeable membrane having a pre-defined molecular weight barrier for separating the glucose oxidase, thereby resulting in a combined hydrogen peroxide and gluconic acid solution. The method can further include at least partially converting the gluconic acid into a gluconate salt, and separating and concentrating the hydrogen peroxide from the gluconic acid or gluconate salt via vacuum flash evaporation and vacuum distillation.

A hydrogen peroxide and gluconic acid production method and system is disclosed that can include receiving an aqueous solution having glucose, water, and glucose oxidase at a reaction chamber. Here, the reaction chamber facilitates an enzymatic reaction between a gas phase and a liquid phase of the aqueous solution, thereby yielding a first solution comprising hydrogen peroxide, gluconic acid, and the glucose oxidase. The method can further include receiving the first solution at a separation chamber, wherein the separation chamber is comprised of a semi-permeable membrane having a pre-defined molecular weight barrier for separating the glucose oxidase, thereby resulting in a combined hydrogen peroxide and gluconic acid solution. The method can further include at least partially converting the gluconic acid into a gluconate salt, and separating and concentrating the hydrogen peroxide from the gluconic acid or gluconate salt via vacuum flash evaporation and vacuum distillation.

The present invention discloses the conversion of non-edible grade organic maize or wheat into monosaccharides by enzyme hydrolysis. The generated glucose at 14-16% is used to produce natural, organic gluconic acid by microbial fermentation of three strains Aspergillus niger NCIM 545, Penicillium notatum NCIM 745 and Penicillium chrysogenum NCIM 709. These strains are improved by unique media constituents and parameters for product yield enhancement along with the reduced time of gluconic acid production by 15-20 h. Further, gluconic acid is fortified with calcium or sodium or magnesium or ferrous to produce respective gluconate salts which were processed by a set of downstream processes including spray drying to obtain in powder form. These organic gluconates have immense applications in food, pharma, feed, and construction sectors for supplying organic source as well as minerals. This route of gluconic acid and its salts production is robust simple, cost-effective and less time taking by using eco-friendly biotechnological processes.

The present invention discloses the conversion of non-edible grade organic maize or wheat into monosaccharides by enzyme hydrolysis. The generated glucose at 14-16% is used to produce natural, organic gluconic acid by microbial fermentation of three strains Aspergillus niger NCIM 545, Penicillium notatum NCIM 745 and Penicillium chrysogenum NCIM 709. These strains are improved by unique media constituents and parameters for product yield enhancement along with the reduced time of gluconic acid production by 15-20 h. Further, gluconic acid is fortified with calcium or sodium or magnesium or ferrous to produce respective gluconate salts which were processed by a set of downstream processes including spray drying to obtain in powder form. These organic gluconates have immense applications in food, pharma, feed, and construction sectors for supplying organic source as well as minerals. This route of gluconic acid and its salts production is robust simple, cost-effective and less time taking by using eco-friendly biotechnological processes.

The disclosure is in the technical field of synthetic biology and metabolic engineering. More particularly, the disclosure is in the technical field of cultivation or fermentation of metabolically engineered cells. The disclosure describes a cell metabolically engineered for production of a mixture of at least four different neutral non-fucosylated oligosaccharides. Furthermore, the disclosure provides a method for the production of a mixture of at least four different neutral non-fucosylated oligosaccharides by a cell as well as the purification of at least one of the oligosaccharides from the cultivation.

The present disclosure provides methods of producing commodity products, the methods involving culturing a host cell that is genetically modified to produce a uronate dehydrogenase (UDH) that converts a sugar acid to its corresponding 1,5-aldonolactone, that uses NADP.sup.+ or NAD.sup.+ as a cofactor, and that produces NADPH or NADH, respectively, where the host cell coexpresses an endogenous or a heterologous reductase that utilizes the produced NADPH or NADH to generate the commodity product or a precursor thereof. The present disclosure provides a method of producing downstream products of glycerol and pyruvate in a genetically modified microbial host cell, the method involving culturing a genetically modified microbial host cell of the present disclosure in a culture medium comprising D-galacturonic acid. The present disclosure provides variant UDH polypeptides that utilize NADP.sup.+, nucleic acids encoding the variant UDH polypeptides; and host cells genetically modified with the nucleic acids.

The present disclosure provides methods of producing commodity products, the methods involving culturing a host cell that is genetically modified to produce a uronate dehydrogenase (UDH) that converts a sugar acid to its corresponding 1,5-aldonolactone, that uses NADP.sup.+ or NAD.sup.+ as a cofactor, and that produces NADPH or NADH, respectively, where the host cell coexpresses an endogenous or a heterologous reductase that utilizes the produced NADPH or NADH to generate the commodity product or a precursor thereof. The present disclosure provides a method of producing downstream products of glycerol and pyruvate in a genetically modified microbial host cell, the method involving culturing a genetically modified microbial host cell of the present disclosure in a culture medium comprising D-galacturonic acid. The present disclosure provides variant UDH polypeptides that utilize NADP.sup.+, nucleic acids encoding the variant UDH polypeptides; and host cells genetically modified with the nucleic acids.

The present invention provides an acid-tolerant Saccharomyces cerevisiae strain and use thereof. By using exogenously added malic acid as a stress, an acid-tolerant mutant S. cerevisiae strain MTPfo-4 is obtained by directed evolution screening in the laboratory, which tolerates a minimum pH of 2.44. The mutant strain MTPfo-4, tolerant to multiple organic acids, has an increased tolerance to exogenous malic acid of up to 86.6 g/L. The mutant strain MTPfo-4 obtained is further identified. The mutant strain grows stably and well, and can tolerate a variety of organic acids (lactic acid, malic acid, succinic acid, fumaric acid, citric acid, gluconic acid, and tartaric acid). It also has a strong tolerance to inorganic acids (HCl and H.sub.3PO.sub.4). This is difficult to achieve in the existing research and reports of S. cerevisiae. The strain is intended to be used as an acid-tolerant chassis cell factory for producing various short-chain organic acids.

The disclosure is in the technical field of synthetic biology and metabolic engineering. More particularly, the disclosure is in the technical field of cultivation or fermentation of metabolically engineered cells. The disclosure describes a method for the production of a di- or oligosaccharide with an N-acetylglucosamine at the reducing end by a cell as well as the purification of the di- or oligosaccharide from the cultivation. Furthermore, the disclosure provides a cell metabolically engineered for production of a di- or oligosaccharide with an N-acetylglucosamine at the reducing end.