The preparation method of a starch-based double-loaded functional nanoparticle includes: performing restrictive hydrolysis treatment on egg high-density lipoprotein using proteases to obtain the polypeptide; performing self-assembling on a mixed system containing the polypeptide and quercetin under the alkaline condition to form a micelle nanoparticle; performing covalent grafting reaction on a mixed system containing the micelle nanoparticle and anthocyanin under the alkaline condition to form a graft; and electrostatically compounding carboxymethyl dextrin with the graft to obtain the starch-based double-loaded functional nanoparticle. In the preparation method, raw materials derived from natural sources are used, and the self-assembled colloid nanoparticle with good properties can be obtained by adjusting the pH without any organic reagents. The obtained product has a nanoparticle size, has high antioxidant activity and stability against environmental stress, and can be widely applied to the fields of delivery of nutrients, stabilization of biologically active substances and the like.

The preparation method of a starch-based double-loaded functional nanoparticle includes: performing restrictive hydrolysis treatment on egg high-density lipoprotein using proteases to obtain the polypeptide; performing self-assembling on a mixed system containing the polypeptide and quercetin under the alkaline condition to form a micelle nanoparticle; performing covalent grafting reaction on a mixed system containing the micelle nanoparticle and anthocyanin under the alkaline condition to form a graft; and electrostatically compounding carboxymethyl dextrin with the graft to obtain the starch-based double-loaded functional nanoparticle. In the preparation method, raw materials derived from natural sources are used, and the self-assembled colloid nanoparticle with good properties can be obtained by adjusting the pH without any organic reagents. The obtained product has a nanoparticle size, has high antioxidant activity and stability against environmental stress, and can be widely applied to the fields of delivery of nutrients, stabilization of biologically active substances and the like.

The present invention relates to a process for the preparation of a fermentable sugar composition, wherein a polysaccharide composition is treated by at least one glucoamylase enzyme and at least one oligo-1,6-glucosidase enzyme, and wherein the fermentable sugars are removed during the process. Thereby, the otherwise non-fermentable sugars can be utilized in the fermentation process to yield a fermentation product such as an alcohol or an organic acid or amino acid.

The present invention relates to a process for the preparation of a fermentable sugar composition, wherein a polysaccharide composition is treated by at least one glucoamylase enzyme and at least one oligo-1,6-glucosidase enzyme, and wherein the fermentable sugars are removed during the process. Thereby, the otherwise non-fermentable sugars can be utilized in the fermentation process to yield a fermentation product such as an alcohol or an organic acid or amino acid.

The disclosure relates to a preparation method of a amylodextrin and belongs to the technical field of starch chemical modification. According to the method, de-clustering and complexation effects of ultrasonic waves are used to achieve de-clustering of a starch chain and complexation of an amorphous region and an emulsifier, and then α-amylase and pullulanase are used to achieve complex enzymolysis. Because the amorphous region and the emulsifier form a complex which is resistant to enzymolysis, the amorphous region is prevented from being destroyed. Finally, dextrins of different molecular weights are separated by a membrane separation method, so as to obtain a amylodextrin product with low polydispersity coefficient and narrow molecular weight distribution, and the starch comprehensive utilization efficiency is increased to 70% or above.

The disclosure relates to a preparation method of a amylodextrin and belongs to the technical field of starch chemical modification. According to the method, de-clustering and complexation effects of ultrasonic waves are used to achieve de-clustering of a starch chain and complexation of an amorphous region and an emulsifier, and then α-amylase and pullulanase are used to achieve complex enzymolysis. Because the amorphous region and the emulsifier form a complex which is resistant to enzymolysis, the amorphous region is prevented from being destroyed. Finally, dextrins of different molecular weights are separated by a membrane separation method, so as to obtain a amylodextrin product with low polydispersity coefficient and narrow molecular weight distribution, and the starch comprehensive utilization efficiency is increased to 70% or above.

The present invention is in the technical field of synthetic biology and metabolic engineering. More particularly, the present invention is in the technical field of fermentation of metabolically engineered microorganisms. The present invention describes engineered microorganisms able to synthesize sialylated compounds via an intracellular biosynthesis route. These microorganisms can dephosphorylate N-acetylglucosamine-6-phosphate to N-acetylglucosamine and convert the N-acetylglucosamine to N-acetylmannosamine. These microorganisms also have the ability to convert N-acetylmannosamine to N-acetyl-neuraminate. Furthermore, the present invention provides a method for the large scale in vivo synthesis of sialylated compounds, by culturing a microorganism in a culture medium, optionally comprising an exogenous precursor such as, but not limited to lactose, lactoNbiose, N-acetyllactosamine and/or an aglycon, wherein said microorganism intracellularly dephosphorylates N-acetylglucosamine-6-phosphate to N-acetylglucosamine, converts N-acetylglucosamine to N-acetylmannosamine and convert the latter further to N-acetyl-neuraminate.

This specification discloses process for obtaining maltodextrin having DE between 17 and 19.9 and the maltodextrins obtained from the process. The disclosed maltodextrins can be provided as a powder or in shelf stable liquid form. The disclose maltodextrins have a polysaccharide profile similar to those observed for prior art maltodextrins, but make maltodextrin solutions having a high solids content, but reduced viscosity compared to prior art maltodextrins, on equivalent solids-in-solution basis. The process combines adds an alpha-amylase and a pullulanase enzyme to a polysaccharide mixture during a saccharification step. The disclosed maltodextrins make solutions at 50° C. and greater than 65% on a solids dry solids basis having a viscosity between 5,000 and 12,000 cP and having a water activity of less than 0.80.

This specification discloses process for obtaining maltodextrin having DE between 17 and 19.9 and the maltodextrins obtained from the process. The disclosed maltodextrins can be provided as a powder or in shelf stable liquid form. The disclose maltodextrins have a polysaccharide profile similar to those observed for prior art maltodextrins, but make maltodextrin solutions having a high solids content, but reduced viscosity compared to prior art maltodextrins, on equivalent solids-in-solution basis. The process combines adds an alpha-amylase and a pullulanase enzyme to a polysaccharide mixture during a saccharification step. The disclosed maltodextrins make solutions at 50° C. and greater than 65% on a solids dry solids basis having a viscosity between 5,000 and 12,000 cP and having a water activity of less than 0.80.

An isoamylase having improved heat resistance and an industrial method for producing maltose from starch.

The isoamylase is an isoamylase consisting of the amino acid sequence represented by SEQ ID NO: 1 or an isoamylase resulting from deletion, substitution, or insertion of one to several amino acid residues in the amino acid sequence represented by SEQ ID NO: 1, wherein at least valine at amino acid number 515 and methionine at amino acid number 570 are mutated to other amino acids.