60 results about "Dpph scavenging" patented technology

The invention relates to a method for increasing the contents of tanshinone and salvianolic acid in a salvia miltiorrhiza hairy root by using a transgene AtMYC2, belonging to the technical field of gene engineering. The method comprises the steps of constructing a high-efficiency expression vector of a plant by using an arabidopsis transcription factor AtMYC2, and carrying out genetic transformation on salvia miltiorrhiza leaves to obtain a gene AtMYC2 overexpressed transgenetic salvia miltiorrhiza hairy root; analyzing the expression of AtMYC2 in the transgenetic salvia miltiorrhiza hairy root and related genes in biosynthetic pathways of tanshinone and salvianolic acid through qRT-PCR; measuring the contents of tanshinone and salvianolic acid in the transgenetic salvia miltiorrhiza hairy root by using a high-performance liquid chromatography (HPLC); and measuring the antioxidant activity of tanshinone and salvianolic acid in the transgenetic salvia miltiorrhiza hairy root by using a DPPH free radical scavenging method. The invention provides the method for simultaneously increasing the contents of tanshinone and salvianolic acid in salvia miltiorrhiza hairy root and also provides a novel high-quality raw material for producing tanshinone and salvianolic acid with important clinic demands so as to have the positive promoting significance and application value for relieving the problem that the drug resources of tanshinone and salvianolic acid are short.

The invention discloses a method for preparing antioxidant peptides from oats. Alcalase is determined to serve as the enzyme for preparation through investigating the antioxidant activities and yields of the products obtained by carrying out enzymolysis on the oat bran proteins with different proteases. Reduction of the enzymolysis speed of the Alcalase toward the oat bran proteins is determined to be mainly caused by substrate consumption and enzyme activity loss through investigating the enzymolysis speed of the Alcalase toward the oat bran proteins. Meanwhile, an enzymatic membrane reactorsystem is determined to have good retention effect on the Alcalase through studying the impact of the enzymatic membrane reactor system on the enzyme activity. The activity loss of the Alcalase is mainly caused by the damage to the enzyme in the operation process of a peristaltic pump and the adsorption of an ultrafiltration membrane toward the enzyme. By utilizing Design Expert 6.0.5 to design the response surface analysis experiment with four factors and three levels, the optimum process conditions under which the antioxidant peptides from oats can be prepared by utilizing the enzymatic membrane reactor are as follows: the substrate concentration is 3%; the enzyme addition is 3.2%; the feed flow rate is 45L/h; the operation pressure is 0.07MPa; the temperature is 55 DEG C; and the pH value is 7.3. Through verification, the DPPH scavenging rate of the products under the conditions can reach 57.39%.

The invention relates to an enzyme product with strong antioxidant activity and a preparation method of the ferment product. The elimination rate of DPPH by the ferment product is not less than 80%, the elimination rate of superoxide anions by the ferment product is not less than 80%, and the elimination rate of hydroxy free radicals by the ferment product is not less than 80%. According to the method disclosed by the invention, one or more kinds of materials of ginger, papayas, lotus roots, Chinese yam, plums, white gourds, bitter gourds, hericium erinaceus, kiwi fruits, grapes, crystal sugar oranges, tomatoes, black beans and bananas are used as raw materials, and fermentation is performed with probiotics, so that the ferment product is prepared.

The invention relates to a technique for preparing squid skin collagen peptide through an enzymic method. The technique includes: pre-treating squid skin which is a raw material, hydrolyzing through alkaline protease, and continuing hydrolysis through composite protease to obtain collagen hydrolysate, wherein the composite protease is composed of papain and flavorzyme. The collagen peptide prepared by the technique is ideal in hydrolysis degree, DPPH removal rate and polypeptide conversion rate, molecular weight of 97.63% of collagen peptide is less than 2000 Da, and the collagen peptide is high in quality and utilization value. The technique has high theoretical guiding significance in subsequent further separation and purification and application of the squid skin collagen peptide.

The invention relates to a method for obtaining active polypeptide by carrying out multi-strain compound solid state fermentation on common rapeseed meal. The common rapeseed meal is taken as raw material, plant lactic acid bacteria, bacillus subtilis and aspergillus oryzae are screened for carrying out mixed bacterium solid state fermentation, and concrete fermentation steps are as follows: inoculating in the ratio of plant lactic acid bacteria to bacillus subtilis to aspergillus oryzae being (1-5): (1-3): (1-3), wherein concentration of inoculated bacterium suspension is 108/mL, after inoculation, fermenting in a fermentation bin, and drying at the temperature of 55 DEG C, thus obtaining the active polypeptide. By adopting the method disclosed by the invention, after fermentation, crude protein content is improved by 10%, polypeptide content is increased by more than 6%, clearance rate of the polypeptide to hydroxyl radical is improved by 14 times, the clearance rate of the polypeptide to superoxide anion is improved by 17 times, and the clearance rate of the polypeptide to DPPH (1,1-diphenyl-2-picrylhydrazyl radical) is improved by 12 times.

The invention belongs to the technical field of the deep-processing of egg products and the comprehensive utilization of side products, and discloses an egg white source antioxidant peptide powder and a preparation method thereof. The egg white source antioxidant peptide powder can be prepared by taking hydrolyzed egg white protein as a raw material and DPPH (1,1-diphenyl-2-picryhydrazyl) free radical scavenging rate and reducing power as antioxidant activity evaluation indexes through using an ultrafiltration device, a vacuum rotating concentration instrument, a column chromatography cabinet system and a vacuum freeze-drying technology. In the egg white source antioxidant peptide powder, the molecular weight is 300-600Da, the protein content is 94.28%, the DPPH scavenging rate is 90.2%, the reducing power is 1.8, and the moisture content is 1%-3%. According to the preparation method, the antioxidant activity of the egg white source antioxidant peptide can be improved, the DPPH scavenging rate is improved to 90.2% from 50%, the reducing power is improved to 1.8 from 1.46, and the research and development level of egg resources on comprehensively utilizing and developing functional products can be beneficially improved.

The invention relates to a micro-molecule polypeptide with a function of removing free radicals. In the biological field related to removal of free radicals, earthworm is a novel high-protein source and is high in content of protein and rich in types of amino acids; an earthworm proteinase product prepared by autolysis of the earthworm or degradation of exogenous proteases has an excellent function of removing free radicals. The micro-molecule polypeptide is extracted from the earthworm and is prepared by the following steps: dispersing the earthworm into slurry, carrying out enzymolysis on the slurry by using different hydrolytic enzymes, carrying out suction filtration and ultrafiltration on enzymatic hydrolysate, concentrating and drying to obtain the micro-molecule polypeptide. The micromolecule polypeptide is low in molecular weight and low in sensitization; the total content of polypeptide with the molecular weight being smaller than 1000Da is over 90%; by virtue of detection of the capability of removing DPPH, the micro-molecule polypeptide has the excellent function of removing the free radicals.

The invention belongs to the technical fields of agricultural product deep processing and comprehensive utilization of byproducts thereof, and relates to a pine nut protein source anti-oxidation peptide and a preparation method thereof. The pine nut protein source anti-oxidation peptide having a molecular weight of 1000-3000Da, a protein content of 95.0-98.0%, an ash content of 0.5-2.5% and a DPPH clearance rate of 80-90% is obtained through carrying out immersion, crushing, homogenizing, protein denaturation, enzymatic hydrolysis, centrifugation, ultrafiltration, concentration and vacuum freeze-drying processes of pine nut meal as a raw material. The raw material is pine nut meal, is processed through using a cold squeezing technology, and does not contact with any organic extraction solvents, so the raw material is unpolluted, and the original quality and functions of pine nut proteins are reserved; and the pine nut protein source anti-oxidation peptide is obtained through efficiently utilizing high-quality proteins in pine nuts on the precise of the low cost and easy obtaining of the raw material, so the environment is protected, the effective value increment utilization of the high-quality protein sources is relied, and the added values of pine nut products are improved.

The invention belongs to the technical field of microorganisms, and discloses streptococcus thermophilus and an enrichment culture method and application thereof. A strain DMST-H2 is separated from homemade yogurt of the Inner Mongolia family, and is preserved in the Guangdong microbial culture collection center (GDMCC) at April 16, 2019, and the preservation number is GDMCC 60642. By optimizing an enrichment culture medium, the viable count of the strain can be increased to 10<9> CFU/mL or above. The viable count under optimal conditions can reach 4.2*10<9> CFU/mL, and is 37.8 times that before the conditions are optimized. The strain is more suitable for intestines of Chinese, and lower in cost. In addition, the strain has the capacity of resisting acid, cholate and artificial gastrointestinal fluid, and meanwhile has the outstanding antioxidant capacity, especially DPPH removal capacity.

The invention discloses an extracellular polysaccharide producing space plant lactobacillus SS18-33 and application thereof to organism anti-oxidization activity improvement. The space plant lactobacillus SS18-33 disclosed by the invention is collected in CGMCC (China General Microbiological Culture Collection Center), and has the preservation number of CGMCC No.15151. The extracellular polysaccharide produced by the space plant lactobacillus SS18-33 has the DPPH clearing capability, superoxide anion free radical (O<2->.) clearing capability, Fe<2+> chelation capability, total reduction capability for blocking peroxide formation on provided hydrogen atom substances or total anti-oxidization capability. In addition, the strain also has the characteristic of gastrointestinal tract inverse environment tolerance; the practical basis is provided for the application of the extracellular polysaccharide to the organism anti-oxidization activity improvement. The extracellular polysaccharide producing space plant lactobacillus SS18-33 fills the study blank of space food microbial engineering bacteria.

The invention relates to the field of milk product processing, and especially relates to antioxidant Cheddar cheese containing lactobacillus plantarum and lactobacillus casei, as well as a preparation method thereof. According to the preparation method, two strains with antioxidant properties, namely the lactobacillus plantarum and the lactobacillus casei, are added into the Cheddar cheese as working ferments so as to increase qualities and antioxidant properties of the Cheddar cheese. The production method of the antioxidant Cheddar cheese containing the lactobacillus plantarum and the lactobacillus casei is characterized in that the Cheddar cheese of which the viable count is up to 6.0 multiplied by 10<7> cfu/ml and the DPPH scavenging capacity up to 51.72% can be prepared by the production method. Integrated functional properties of the Cheddar cheese and the two stains of the probiotics can be simultaneously played so as to effectively solve the problems of oxidation posed to human human health and food preservation.

The invention discloses a ginkgo leaf and flos sophorae compound drink and a preparation method thereof. The compound drink includes the following specific components in parts by mass: 50-80 parts of flos sophorae extract liquid, 70-100 parts of ginkgo leaf extract liquid, 2-4 parts of aspartame and 0.8-1.2 parts of citric acid. The preparation method is as follows: (1) preparing the flos sophorae extract liquid; (2) preparing the ginkgo leaf extract liquid; and (3) mixing the flos sophorae extract liquid, the ginkgo leaf extract liquid, the aspartame and the citric acid in proportion for 20-40 min so as to obtain the compound drink. The compound drink provided by the invention has a soothing effect on the human cardiac and cerebral blood vessels, has a relatively high TBA inhibition ratio, a relatively high hydroxyl free radical clearance ratio and a relatively high DPPH free radical clearance ratio and also meets the standard of low energy.

The invention relates to an antioxidant and application thereof, and relates to application of chlorella polysaccharides in preparation of plant green pesticides and food additives. The chlorella polysaccharides are a group of polysaccharides with a molecular weight of 10.6-13.6kDa, and are prepared from water-insoluble chlorella part (algal residue) by enzymolysis, deproteinization and alcohol precipitation, and the monosaccharide is mainly composed of glucose, galactose, arabinose, fucose and rhamnose. The chlorella polysaccharides can significantly improve plant cell antioxidase (SOD, POD and CAT) (superoxide dismutase, peroxidase and catalase) and in-vitro hydroxyl free radical clearance rate, reducing power, DPPH (1,1-diphenyl-2-picrylhydrazyl radical) clearance rate and other activity, and can be used as a plant growth regulator and a natural food additive.

The invention discloses a method for rapid activation of antioxidant activity of a 1,000-10,000Da egg white peptide component, belongs to the technical field of subsidiary agricultural products deep processing and comprehensive utilization of byproducts thereof, and relates to a method for rapid activation of antioxidant activity of a 1,000-10,000Da egg white peptide component using a high-voltage pulse electric field technique. The method uses a 1,000-10,000Da egg white peptide component with a DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging rate of 30% as a raw material, adopts a high-voltage pulse electric field technique, realizes the key technical invention for peptide activation by electrodes within 2,500mus and rapid increase of the DPPH free radical scavenging rate up to over 70% through preparation of egg white antioxidant peptide liquid, regulation of high-voltage pulse electric field device activation parameters, regulation of peptide liquid constant flow rate, high-voltage pulse electric field activation treatment and vacuum freeze drying processes, and can open a new route for comprehensive utilization of egg white resources.

The invention discloses a method for quickly improving anti-oxidation activity of a 10-30kDa egg white protein peptide, belonging to the technical field of fine deep processing of agricultural sideline products and comprehensive utilization of by-products, particularly relating to a technique with high-voltage pulse electric field treatment as a core. With 10-30kDa egg white protein peptide as a research object and a DPPH (1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl) clearance rate and an FRAP (Fluorescence Recovery After Photobleaching) value as main indexes for balancing the anti-oxidation activity, the time that a material flow passes through double electrodes of a high-voltage pulse electric field is optimized to be within 50-2,000 microseconds depending on the high-voltage pulse electric field technique, thus the DPPH clearance rate of the anti-oxidation activity of the egg white protein peptide is improved from 64% to 80.4%, the FRAP value of the egg white protein peptide is improved from 1.32 to 1.52, the stability of the egg white protein peptide is prolonged from 3h to 8h, and the purposes of quickly improving the anti-oxidation activity and reinforcing the stability are realized. The method for quickly improving the anti-oxidation activity of the 10-30kDa egg white protein peptide, disclosed by the invention, not only provide a new idea for the technical research on quick improvement of the anti-oxidation activity of the egg white protein peptide, but also provides a new way for development and application of high-activity egg white protein peptide series products.

The present invention belongs to the field of processing of dendrobium officinale kimura et migo, and particularly relates to a method for preparing dendrobium officinale kimura et migo oligosaccharide having an in vitro anti-oxidation activity. According to the present invention, the dendrobium officinale kimura et migo oligosaccharide is prepared by using the enzymolysis method, the method is simple and has the strong practicality, and the prepared dendrobium officinale kimura et migo oligosaccharide has the DPPH removal rate of 23.7% and the total anti-oxidation activity of 0.65 U/mL.

The invention discloses a method for extracting flavone substances in Camellia nitidissima. The method includes the steps of a, drying the Camellia nitidissima, and crushing to obtain a product A; b,extracting the product A with ethanol to obtain Camellia nitidissima flavone substance extract, wherein the volume fraction of the ethanol during extraction is 50-90%, the solid-liquid ratio of the product A to the ethanol is 1:(10-50)g/mL, extraction temperature is 40-80 DEG C, and extraction time is 40-80 minutes. The method is high in Camellia nitidissima flavone substance extraction rate, theextraction rate of the optimal extraction process is 5.99%, the extracted flavone substances are good in oxidation resistance and good in eliminating ability, the DPPH eliminating rate of the extracted flavone substances can reach 80%, the ABTS eliminating rate of the extracted flavone substances can reach 85%, and the method is of great significance to the increasing of the additional value of the Camellia nitidissima and can provide a certain theoretical foundation for the further increasing of the comprehensive utilization value of the Camellia nitidissima.