49 results about "Alpha-amylase activity" patented technology

The present invention relates to a method of constructing a variant of a parent Termamyl-like alpha-amylase, which variant has alpha-amylase activity and at least one altered property as compared to the parent alpha-amylase, comprisesi) analysing the structure of the parent Termamyl-like alpha-amylase to identify at least one amino acid residue or at least one structural part of the Termamyl-like alpha-amylase structure, which amino acid residue or structural part is believed to be of relevance for altering the property of the parent Termamyl-like alpha-amylase (as evaluated on the basis of structural or functional considerations),ii) constructing a Termamyl-like alpha-amylase variant, which as compared to the parent Termamyl-like alpha-amylase, has been modified in the amino acid residue or structural part identified in i) so as to alter the property, and, optionally,iii) testing the resulting Termamyl-like alpha-amylase variant with respect to the property in question.

The present invention relates to variants (mutants) of polypeptides, in particular Termamyl-like alpha-amylases, which variant has alpha-amylase activity and exhibits an alteration in at least one of the following properties relative to said parent alpha-amylase: substrate specificity, substrate binding, substrate cleavage pattern, thermal stability, pH/activity profile, pH/stability profile, stability towards oxidation, Ca²⁺ dependency, specific activity, and solubility, in particular under production conditions.

The invention relates to alpha amylases and to polynucleotides encoding the alpha amylases. In addition methods of designing new alpha amylases and methods of use thereof are also provided. The alpha amylases have increased activity and stability at increased pH and temperature.

The invention provides a new use of a macrocyclic polyphenol compound separated from a penthorum chinense pursh extract in pharmacy. The macrocyclic polyphenol compound comprises a compound 1, a compound 2, a compound 3 and a compound 4, wherein the structural formulas of the compounds are as shown in the specification; the compounds have the following pharmacological activities that (1) the alpha-amylase activity is significantly inhibited, and the compounds have certain hypoglycemic effects, and (2) TGF (transforming growth factor)-beta1-induced hepatic stellate cell proliferation is significantly inhibited, and the compounds have anti-liver-fibrosis effects by pharmacology and efficacy experiments. The invention provides a novel medicament for preventing and treating diabetes mellitus, and an anti-liver fibrosis medicament. The medicament is abundant in raw material source, small in side effect, and beneficial to environmental protection, and has a relatively great clinical application value.

The present invention relates to a method for identifying a pepsin resistant alpha amylase enzyme for use in a feed supplement comprising: i) providing an alpha amylase enzyme; ii) admixing said alpha amylase with corn based feed and buffer solution comprising a pepsin concentration of 9000 U/ml at pH 3, 40° C., 500 rpm for at least 120 minutes and analysing alpha amylase activity on said alpha amylase compared to a control sample; wherein said control sample differs in that no pepsin is present during incubation; and iii) selecting an alpha amylase enzyme which substantially maintains alpha amylase activity under the assay conditions; feed supplements and feedstuffs comprising a pepsin resistant alpha amylase and the use of pepsin resistant alpha amylases in feed.

The present invention relates to processes for producing a fermentation product comprising (a) saccharifying starch-containing material below the initial gelatinization temperature in the presence of i) from 0.001-50 AGU/g DS, preferably 0.01 to 10 AGU/g DS alpha-glucosidase activity more than the native amount of endogenous alpha-glucosidase present in the starch-containing material, and ii) from 0 (zero) to 10 FAU-F/g DS of alpha-amylase activity, and (b) fermenting using a fermenting organism. The invention also relates to an enzymatic composition for use in a process of the invention.

The present invention relates to a method of constructing a variant of a parent Termamyl-like alpha-amylase, which variant has alpha-amylase activity and at least one altered property as compared to the parent alpha-amylase, comprises i) analysing the structure of the parent Termamyl-like alpha-amylase to identify at least one amino acid residue or at least one structural part of the Termamyl-like alpha-amylase structure, which amino acid residue or structural part is believed to be of relevance for altering the property of the parent Termamyl-like alpha-amylase (as evaluated on the basis of structural or functional considerations), ii) constructing a Termamyl-like alpha-amylase variant, which as compared to the parent Termamyl-like alpha-amylase, has been modified in the amino acid residue or structural part identified in i) so as to alter the property, and, optionally, iii) testing the resulting Termamyl-like alpha-amylase variant with respect to the property in question.

A high temperature alpha-amylase and a high efficiency preparation method of the mutant thereof belongs to the fermentation engineering field. The invention provides a method for high efficiently secreting expressing a high temperature alpha-amylase and mutant thereof with alpha-amylase activity through a bacillus, especially a bacillus licheniformis mutant strain as a host cell. The synthesis and secretion level of the high temperature alpha-amylase or mutant thereof of the recombinant strain of the invention reaches 18-25mg/mL during fed-batch fermentation and is 3-4.5 times of the original strain high temperature alpha-amylase synthesis level. The high temperature alpha-amylase of the invention is useful for reducing the fermentation manufacture cost of the industrial enzyme, simplifying the fermentation manufacture process and reducing fermentation industrial environment pressure.

The invention relates to alpha amylases and to polynucleotides encoding the alpha amylases, and methods of making and using them. In addition methods of designing new alpha amylases and methods of use thereof are also provided. The alpha amylases have increased activity and stability at increased pH and temperature.

The invention relates to a method and an application for improving fermentation enzyme production of bacillus licheniformis by knocking out spoIIQ and pcf genes. Recombinant (B. licheniformis) DL-1 delta spoIIQ delta pcf is acquired by knocking out the spoIIQ and pcf genes, spore forming rate is reduced to 0.16%, and recombinant bacterium alpha-amylase activity is improved by 10.9% in flask shaking fermentation culture and improved by 19.3% in 5L fermentation culture. According to the method, fermentation activity of target enzymes of the bacillus licheniformis is improved to some extent, strain fermentation production performances are improved, and ideals and method reference can be provided for genetic engineering breeding of industrial microorganisms.

The present invention relates to an α-amylase activity inhibitor, and to food and beverages comprising the α-amylase activity inhibitor. The α-amylase activity inhibitor of the present invention exhibits remarkably excellent α-amylase inhibitory activity as compared with guava extract. Accordingly, food and beverages containing the α-amylase activity inhibitor are diet food and beverages suitable for people of high blood-sugar level or hyderlipidemia.

The invention discloses a preparing method of thermophilic alpha-amylase (PFA), which comprises the following steps: heating and dissolving recombinant protein inclusion body under the condition of alkalinity; diluting; compositing; separating and purifying through column layer. This method possesses high reclaiming ratio and high alpha-amylase activity.

The present invention relates to polypeptides having alpha-amylase activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

The invention relates to rhizomucor miehei alpha-amylase, and an encoding gene and an application of the rhizomucor miehei alpha-amylase. A protein has alpha-amylase activity; the gene of the proteinis efficiently expressed in pichia pastoris; the maximum enzyme activity after high density fermentation of the pichia pastoris is 29794.2U/mL; the specific enzyme activity after purification is 3502.1U/mg; an optimum reaction pH (potential of hydrogen) is 6.0; the protein keeps stable when the pH is 4.5-8.0; an optimum reaction temperature is 75 DEG C; and the protein keeps the higher enzymic activity below 65 DEG C and has better thermal resistance. The amylase can increase a specific volume of steamed bread by 7.7% and retard aging of the steamed bread when the amylase is applied to the steamed bread; and a maltose content can reach 54.1% when the amylase is applied to maltose production. The amylase has good utilization potentiality in the food industry.

The present invention relates to isolated polypeptides having alpha-amylase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

The present invention relates to isolated polypeptides having alpha-amylase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

The invention provides a cyclocarya paliurus leaf solid beverage, as well as a preparation method and application thereof. The solid beverage is prepared from the following components in parts by weight: 1g-3g of cyclocarya paliurus water-soluble polysaccharides, 1g-3g of cyclocarya paliurus flavone, 0.1g-0.5g of cyclocarya paliurus triterpene, 95g-98g of cyclocarya paliurus leaf raw powder, 5g-60g of inulin and 5g-60g of wheat aleurone layer. The cyclocarya paliurus leaf solid beverage is high in active ingredient (including cyclocarya paliurus polysaccharides), solubility, is beneficial to small intestine absorption of effective ingredients, and can be used for remarkably improving the bioavailability of the preparation. The ingredients of the cyclocarya paliurus leaf solid beverage can be well synergized, and has an alpha-amylase activity inhibition effect remarkably superior to that of conventional cyclocarya paliurus tea.

The invention belongs to the technical field of biological fermentation engineering and particularly relates to a method of improving alpha-amylase activity in bacillus subtilis fermentation liquid. A bacillus subtilis strain genome is modified by a gene engineering method, and the method particularly comprises the steps of PCR clonal expansion of sdpBC partial sequence DNA, enzyme digestion and connection, conversion, screening, identification, conversion from homologous single exchange recombinant plasmid to bacillus subtilis 168, detection and identification. According to the method, a bacillus subtilis 168 strain having a relatively clear physiology and conversion background and completing sequencing is taken as a research example, and a sporulation delay protein gene sdpC is subjected to insertion mutation by a homologous recombination method. A preliminary study shows that the viable count and the alpha-amylase activity of the modified strain obtained by the method are better increased and improved, the strain has a better application value, and an application foundation is laid for modification of other strains.

The invention discloses combined amylase and an application thereof, the combined amylase comprises medium-temperature alpha-amylase, pullulanase and glucoamylase, and the ratio of pullulanase activity (u) to medium-temperature alpha-amylase activity (u) to glucoamylase activity (u) is 1: 5-10: 50-80; wherein a fermentation strain of the medium-temperature alpha-amylase is bacillus subtilis, the fermentation strain of pullulanase is bacillus subtilis, and the fermentation strain of glucoamylase is aspergillus niger. According to the combined amylase provided by the invention, the feed intake of piglets is increased and the growth performance of the piglets is improved by regulating and controlling the reducing sugar generation rate, the digestibility of starch in a feed can be effectivelyimproved by adding the combined amylase, the feed intake of the piglets is remarkably increased, and the combined amylase has a wide application prospect.

The invention discloses a preparation method of Southeast Asia herbal medicine combination (cassia auriculata, ficus deltoidea and orthosiphon aristatus) extract, and application thereof in inhibiting alpha-amylase activity and antioxidant activity. Active ingredients are medium-polarity active ingredients obtained by activity screening of inhibiting alpha-amylase activity and antioxidant activity of cassia auriculata, ficus deltoidea and orthosiphon aristatus extracts. The preparation process is environment-friendly and safe, steps are simple and unique, and the obtained extract is good in stability and lasting in effect and can be used for adjuvant therapy of diabetes as well as resistance to inflammation and aging.

The present invention relates to polypeptides having alpha-amylaseactivity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

The invention relates to the technical field of medicine, in particular to a novel berberine drug as well as a preparation method and an application thereof in preparation of drugs for treating diabetes. The chemical structural formula of the compound is shown in formula I, and the compound overcomes the defects of poor solubility and low bioavailability of berberine. An alpha-amylase activity inhibition experiment on the compound verifies that the compound can be used for treating diabetes.

The invention discloses a soluble starch resonance scattering spectra method for detecting Alpha-amylase activity. The resonance scattering strength I423nm of Alpha-amylase with known enzyme activity and the resonance scattering strength I0 of reagent blank are utilized for working out Delta I423nm which is equal to the difference between I423nm and I0 and is used as a standard curve. Then, Delta I of Alpha-amylase with unknown concentration is determined. The concentration of Alpha-amylase of an object to be determined is worked out according to a working curve. The soluble starch resonance scattering spectra method has the advantages of simple equipment, convenient operation, easily obtained reagent and low cost. And the method can be finished just through a spectrophotometer. The soluble starch of substrates is nontoxic.