32 results about "Lactase Enzyme" patented technology

An enzymatic process to obtain 4-O-β-D-galactopyranosyl-D-xylose useful in compositions or solutions in the in vivo evaluation of intestinal lactose activity in humans, that comprises the steps of preparing a reaction mixture of D-xylose, a β-D-galactopyranoside and a reaction medium that comprises water buffered to a pH between 5.0 and 9.0; adding 10 to 1,000 units of β-D-galactosidase per gram of β-D-galactopyranoside; subjecting the reaction mixture to a reaction or a temperature between a temperature higher than the freezing point of the reaction mixture and 45° C., for 2 to 48 hours; for the reaction by deactivation of the β-D-galactosidase; and to isolate and crystallize the fractions that contain 4-O-β-D-galactopyranosyl-D-xylose from a crystallization mixture selected between mixtures of acetone / methanol in a ratio between 5 / 1 to 20 / 1 and mixtures of acetone / water in a ratio between 5 / 1 to 20 / 1.

The test of the invention comprises the measuring the total amount of xylose in urine and / or its concentration in blood following oral administration of 4-O-β-D-galactopyranosyl-D-xylose (4-GX) to the patient. It is a non-invasive test that is based on the direct evaluation of the global enzyme activity in the whole individual, not on measuring the metabolic consequences derived from its deficiency. It does not require specialized equipment, does not cause apparent discomfort in patients with lactase deficiency and is very reliable, thus overcoming the drawbacks of the diagnostic tests currently in use and is a statistically significantly better test in terms of its reliability; consequently it should become the reference or gold standard test for the indication of hypolactasia.

The invention relates to a method for preparing condensed milk with caramel flavor, which at least includes the following steps: (1) Raw milk preparation: fresh milk is filtered, milk is cleaned, sucrose syrup is added, and sucrose and water are dissolved in a ratio of 6.65:10 , and then mix the dissolved milk solution with the sucrose solution; (2) Add sugar: add 0.25‑1.0% glucose or fructose syrup to the solution prepared in step (1); (3) hydrolyze with lactase; (4) Protease hydrolysis; (5) Homogenization; (7) Concentration; (8) Homogenization; (9) Cooling; (10) Crystallization. By adopting the above technical solution, the present invention provides a method for preparing condensed milk with caramel flavor. The lactose produced has caramel flavor, good color and good taste, and can inhibit the absorption of sucrose in the small intestine and lower blood sugar. The content is suitable for people with high blood sugar and diabetes.

The invention discloses a preparation method of a high-activity composite enzyme for feed, belonging to the technical field of preparation of an enzyme preparation for feed. An Aspergillus niger DM-18 strain for a high-yield composite enzyme for feed, which is used as an initial strain, is subjected to liquid submerged mixed fermentation in an optimized culture medium under specific fermentation conditions by an improve fermentation technique to obtain the composite enzyme for feed, which has the advantages of complete enzymatic system, high enzyme activity, high temperature resistance and wide pH value resistance range. The prepared crude enzyme fermentation liquid contains multiple enzyme activities, wherein the proteinase activity is 6500-6700 U / ml, the mannase activity is 1500-1700 U / ml, the alpha-galactase activity is 1200-1300 U / ml, and the pectinase activity is 1000-1200 U / ml. The enzymes still have higher enzyme activity (up to 80% or above) at 30-75 DEG C under the pH value of 2-7; and thus, the composite enzyme is more suitable for the demands of a processing technique in feed industry, and the processed feed has low loss of enzyme activity.

The invention belongs to the technical field of enzyme engineering, and particularly relates to a lactase for generating galacto-oligosaccharides and its preparation and application. The present invention carries out molecular evolution on the basis of two sources of lactase (BglD305 derived from Bacillus circulans B2301 and BglD derived from Bacillus circulans ATCC 31382) molecules to obtain high efficiency of synthesizing galacto-oligosaccharides and good expression performance and construct a high-yielding strain of lactase, which can efficiently synthesize lactase and secrete the enzyme protein molecule into the medium during submerged fermentation, and directly prepare a highly active enzyme preparation from the fermentation supernatant. The expression level can reach 2208U / mL, which is helpful to reduce the fermentation manufacturing cost of lactase, simplify the fermentation manufacturing process and improve the quality of the lactase enzyme preparation.

The present invention relates to a novel improved method of expressing these natural lactases in a natural host of the natural lactases. The invention comprises a method for homologous and heterologous expression of lactase in lactic acid bacteria with altered expression kinetics.

The present invention relates to a nucleic acid molecule that causes or indicates human-type intestinal lactase deficiency and comprises the 5' portion of the intestinal lactase-phlorizin hydrolase (LPH) gene, the nucleic acid molecule being selected from the group consisting of: (a) having or comprising SEQ The nucleic acid molecule of the nucleic acid sequence of ID NO:1, the sequence of SEQ ID NO:1 is also described in Figure 4 and is included in the sequence described in Figure 8; (b) has or comprises the nucleic acid of the nucleic acid sequence of SEQ ID NO:2 Molecule, the sequence of SEQ ID NO: 2 is also described in Figure 5 and is included in the sequence described in Figure 9; (c) a nucleic acid molecule of at least 20 nucleotides, the complementary strand of which is under stringent conditions with (a ) or (b) nucleic acid molecule hybridization, wherein said polynucleotide / nucleic acid molecule has a cytosine residue at a position corresponding to the 5'-13910 position of the LPH gene; and (d) at least 20 nucleosides A nucleic acid molecule of acid, the complementary strand of the nucleic acid molecule hybridizes with the nucleic acid molecule of (a) or (b) under stringent conditions, wherein said polynucleotide / nucleic acid molecule is at the 5'-22018 site corresponding to the LPH gene There is a guanine residue in the position. The present invention also relates to a method for testing the presence or susceptibility of human-type intestinal lactase deficiency based on the analysis of the SNPs contained in the above-mentioned nucleic acid molecules. Furthermore, the present invention relates to diagnostic compositions and kits for detecting the presence or susceptibility to human-type intestinal lactase deficiency.