470 results about "Gamma-polyglutamic Acid" patented technology

The invention relates to a fertilizer prepared by utilizing Gamma-polyglutamic acid, fertilizers and adsorbents. The fertilizer can be used directly, reduce the fertilizer loss, reduce the fertilizer use level, improve the fertilizer utilization ratio, lower the production cost and reduce the environmental pollution. Compared with the normally used fertilizer with the same nutrient elements, the fertilizer use level can be reduced by 20 to 30 percent and the yield can be increased by 10 to 15 percent.

The present invention provides one kind of gamma-polyglutamic acid generating bacterium and the process of preparing gamma-polyglutamic acid (gamma-PGA) therewith. The gamma-polyglutamic acid generating bacterium is Bacillus substilis CCTCC M 206102. The preparation process of gamma-PGA includes using Bacillus substilis CCTCC M 206102 as fermenting strain, and shake flask fermentation of sugar material without adding L-glutamic acid. The present invention has relatively low material cost, gamma-PGA output up to 18g/L and excellent industrial application foreground.

The invention discloses a preparation method of biocompatible gamma-polyglutamic-acid hydrogel, which comprises the following steps of: by using polyglutamic acid as a main raw material and a biological-source material chitosan oligosaccharide as a cross-linking agent, carrying out preparation reaction in an aqueous solution, and activating a gamma-polyglutamic-acid carboxyl group by utilizing activating agents diamine carbide and N-hydroxysuccinimide ester to enable the polyglutamic acid and the free amino group of the chitosan oligosaccharide to form an amido bond to further form the hydrogel in a three-dimensional netted structure. After the prepared gel is swelled and balanced, drying is carried out by adopting a freeze-drying, vacuum-drying or microwave-drying mode. The biological-source material chitosan oligosaccharide is selected as the cross-linking agent, so that the biocompatibility of an obtained hydrogel system can be markedly improved; and a reaction system is an aqueous-solution system, reaction regulating and controlling properties are good, and the gel is stable. Because the hydrogel prepared by the method disclosed by the invention has good biocompatibility, the hydrogel can be widely applied to medicament carriers, auxiliary wound materials, medical and sanitary articles and the like.

The invention provides an antibacterial hydrogel composite material and a preparation method thereof. The antibacterial trauma repair material is hydrogel formed by chitosan and gamma-polyglutamic acid according to a mass ratio of 1/0.5-2 through electrostatic interaction, and nano silver is synthesized and loaded in situ on the hydrogel by taking PVP as a dispersant. the preparation method is simple, convenient and quick, and the trauma repair material is high in practicability. The composite hydrogel trauma repair material integrates bactericidal and immune activity, high biocompatibility and hemostatic activity that chitosan has, high water absorbency that gamma-polyglutamic and broad-spectrum antibacterial property and freeness of drug resistance that nano silver has, and composite hydrogel nano silver is small in grain diameter, uniform in distribution and less prone to aggregation, thereby having high antibacterial performance; when the material is used for wound dressing, wound infection can be avoided effectively, and wound healing can be accelerated.

The present invention is process of preparing poly-gamma-glutamic acid in mixed culture system of Bacillus subtilis and Corynebacterium glutamicum. Bacillus subtilis strain and Corynebacterium glutamicum strain are cultured in culture medium containing carbon source, nitrogen source, inorganic salt and biotin and under optimized condition to obtain poly-gamma-glutamic acid fermenting liquor, which is treated through deposition in organic solvent, dialysis and drying to obtain poly-gamma-glutamic acid. The process has low production cost and high yield.

The invention discloses a strain for synthesizing gamma-polyglutamic acid. The strain is screened from soil around a chemical fertilizer plant and is classified to be named as Bacillus Subtilis NS-9, the collection number of the strain in the China Center for Type Culture Collection (CCTCC NO.) is M2014142, and the collection date of the strain is April 23, 2014. The invention also discloses a method for efficiently preparing gamma-polyglutamic acid by using the strain for synthesizing gamma-polyglutamic acid. Compared with an existing gamma-polyglutamic acid production technique, the adopted bacillus subtilis microbial strain disclosed by the invention can be used for efficiently producing gamma-polyglutamic acid by virtue of fermentation; by optimizing the culture conditions of the bacillus subtilis strain, particularly replenishing a carbon source, inorganic salts and energy substances in a fermentation process, the content of gamma-polyglutamic acid in a fermentation solution can reach 100-200g/L, so that the method for preparing gamma-polyglutamic acid, disclosed by the invention, is high in efficiency and low in cost.

The invention provides a microbial flocculating agent prepared through using two bacilli. The bacilli comprise Bacillus megaterium and Bacillus subtilis, wherein the Bacillus subtilis can generate a high-molecular biobased material gamma-polyglutamic acid, and two broths of the two bacilli are mixed and are added with a suspension substance to flocculate the suspension substance and generate a solid flocculating constituent. The microbial flocculating agent can substitute chemical flocculating agents, can be safely used in various industrial sewage processing industries, the food industry and the medicine industry, and has a popularization prospect.

The invention discloses a seed coating, which is characterized by being formed by mixing 65-80% of gamma-polyglutamic acid, 15-30% of dispersant, 0.5-2% of bonder, 0.05-1% of surfactant, 0.05-2% of biocide and 0.1-0.5% of vigilant dye by weight percent. According to the seed coating taking polyglutamic acid as a primary component, the seed growth microenvironment can be improved, the germination of seeds and the growth and development of seedlings can be promoted, the quality of rice seedlings can be improved, the pesticide effect of pesticides can be improved, the pesticides diffused in the environment and the contact amount of non targets can be reduced, no residues are generated on the leaf surfaces, the disease prevention and pest control effects of the seed coating are improved, and the requirements of green ecological agriculture development are met.

The invention discloses a strain of gamma-polyglutamic acid producing bacterium. The gamma-polyglutamic acid producing bacterium is classified and named as Bacillussubtilis PGS-1 and is collected in China General Microbiological Culture Collection Center (CGMCC), wherein the collection number of a bacterial strain is CGMCC No.4034; and the collection date is July 23rd, 2010. The invention also discloses a method for preparing gamma-polyglutamic acid and salts thereof by using the gamma-polyglutamic acid producing bacterium. Compared with the prior art, the gamma-polyglutamic acid synthesized by the gamma-polyglutamic acid producing bacterium of the invention has the advantages of lower molecular weight (300 to 400 KDa), narrower molecular weight distribution, suitability for the field of application with a low molecular weight requirement and extremely wide application prospects.

The invention provides a preparation method of natural polyelectrolyte-based core-shell structured nano-fiber. According to the invention, natural products of hyaluronic acid, sodium polymannuronate, heparin, gamma-polyglutamic acid, chitosan, and epsilon-polylysine, and synthesized polymers of polyoxyethylene, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol and polycaprolactone are adopted as raw materials; a soluble composite solution of the materials are prepared; and the natural polyelectrolyte-based core-shell structured nano-fiber is prepared with a high-pressure electrospinning technology. According to the invention, polyelectrolyte and synthesized polymers are separated through the induction of electric fields, such that the core-shell structured nano-fiber is successfully prepared. The nano-fiber prepared by the invention has special potential application in respects such as bioactive compound or medicine packaging, chemical modification, cell stents, medicine releasing, and gene transferring.

A process for preparing gamma-polyglutamic acid and polyglutamate includes such steps as culturing bacillus, such as Bacillus subtilis and lichen bacillus, in the culture medium containing carbon source, nitrogen source and Glu to obtain high-activity (1-10 U/ml) gamma-glutamyl transpeptidase, preparing high-concentration fermented liquid of gamma-polyglutamic acid, and solvent precipitation or chemical precipitation.

The invention relates to Bacillus licheniformis P-104 for gamma-PGA (gamma-polyglutamic acid) fermentation production and applications thereof. The Bacillus licheniformis P-104 is conserved in China General Microbiological Culture Collection Center (CGMCC) on September 14, 2010 with the conservation number of CGMCC NO.4156. The Bacillus licheniformis P-104 is obtained by screening and separating the Chinese traditional fermented bean paste product, and has the advantages of short production period, high production efficiency and low production cost. By using the strain and fermentation method thereof provided by the invention, the output of a 7 L fermentation tank of gamma-PGA can reach 32 g/L, and the fed-batch fermentation yield reaches 41.6 g/L.

The invention provides a preparation method of a gamma-polyglutamic acid/Pulullan composite hydrogel. The hydrogel contains gamma-polyglutamic acid, Pulullan and water. The preparation method comprises the following steps: dissolving 8-20% of gamma-polyglutamic acid in distilled water to obtain a first reaction solution; adding Pulullan according to different gamma-polyglutamic acid/Pulullan ratios to obtain a second reaction solution; and adding a crosslinking agent into the second reaction solution, stirring uniformly, regulating the pH value of the system, and reacting at 50 DEG C for 24 hours. The gamma-polyglutamic acid/Pulullan composite hydrogel prepared by the method has favorable adsorbability for brine. The hydrogel is applicable to a brine environment, and is especially applicable to an environment of soil, sweat, blood or the like.

The invention relates to crosslinked polyglutamic acid hydrogel and a preparation method thereof, wherein the crosslinked polyglutamic acid hydrogel is stable, uniform in dispersion and low in concentration. The preparation method comprises the following steps of firstly, adopting a high concentration crosslinking formula for preparing gamma-polyglutamic acid rubber blocks, then, adding a water-based solution for homogenizing and crushing the gamma-polyglutamic acid rubber blocks, and obtaining the crosslinked polyglutamic acid hydrogel which is stable, uniform in dispersion and low in concentration. The preparation method of the crosslinked polyglutamic acid hydrogel which is stable, uniform in dispersion and low in concentration is few in step, stable in product character and suitable for industrial production and application; by controlling the concentration of crosslinked polyglutamic acid in a product, series products with improved viscosity can be obtained, the products are prone to being hydrated so that the products can be uniformly applied to and dispersed on the skin surface, and no sticky or flaking phenomenon occurs to the skin surface.

The invention discloses an agricultural granular zinc sulfate fertilizer which comprises zinc sulfate and a spray liquid, wherein the spray liquid comprises the following components in parts by mass: 10-30 parts of synergist, 0-10 parts of binding agent and 75-90 parts of water; the mass ratio of the zinc sulfate to the spray liquid is (80-95):(20-5); and the synergist is a high molecular polymer, and comprises one or more of gamma-polyglutamic acid and salt thereof, polyaspartic acid and salt thereof, alginic acid and salt thereof and fungal polysaccharide. The invention also discloses a preparation method of the agricultural granular zinc sulfate fertilizer. Compared with the prior art, the agricultural granular zinc sulfate fertilizer has the advantages of low zinc nutrient release speed and long fertilizer efficiency, reduces the loss of zinc nutrient, and can be easily absorbed and utilized by plants; and the high molecular polymer can be easily degraded under natural environment conditions and is environment-friendly.

The invention discloses a bacillus subtilis and a Gamma-polyglutamic acid preparation method that uses the bacillus subtilis strain. The strain is bacillus subtilis XN01 and is preserved in China Center for Type Culture Collection (CCTCC) on March 18th, 2008 with CCTCC NO. of M 208044; the Gamma-polyglutamic acid can be prepared with the strain through the steps of strain cultivation and preservation, seed fluid preparation, shaking fluid fermentation and Gamma-polyglutamic acid extraction. The Gamma-polyglutamic acid preparation method can achieve high synthesis efficiency of Gamma-polyglutamic acid in a low-cost fluid culture medium, is simple and has strong operability.

The invention provides a preparation method of gamma-polyglutamic acid, the method uses Bacillus subtilis PGA-7 CCTCC M 206102 as a fermentation strain to carry out the flask-shaking fermentation of a fermentation culture medium so as to prepare the gamma-polyglutamic acid, and the process comprises the slant strain activation, the liquid activation of the strain, the flask-shaking fermentation and the flask-shaking fermented mash extraction. The preparation method adopts the preferential fermentation raw materials combined by a variety of organic nitrogen sources and inorganic nitrogen sources, the highest gamma-PGA production can be 27.3g/l under the best flask-shaking fermentation process conditions, thereby having good industrial application prospect.

The invention relates to the application of the gamma-polyglutamic acid as the absorption promoting agent of the fertilizer in the agricultural husbandry. The said gamma-polyglutamic acid is a high molecular polymer of D-glutacid and L- glutacid formed by the alpha-amino and the gamma-carboxyl in the manner of peptide bond and there is also a dissociative carboxyl on the alpha-carbon atom of every repetitive unit with average molecular weight of 10-10,000 kilodaltons. The said gamma-polyglutamic acid can be used as the absorption promoting agent of the fertilizer made of single element of nitrogen, phosphor, kalium or their composition. The significance of the invention is: it can be degraded by edaphon and its environmental value is much better in relation to TPA; it can reduce by 10-30 % of the normal usage of the chemical fertilizer by applying 10-50 grams of fertilizer per area and increase by 10-30 % of the crop yield, at the same time it can improve the crop quality and increase the crop content of nitrogen, phosphor and kalium.

The invention discloses a high-efficiency production method of gamma-polyglutamic acid, and belongs to the technical field of production of polymer materials based on biological fermentation. According to the method, bacillus licheniformis CGMCC (China General Microbiological Culture Collection Center) NO.3336 for high-efficient production of gamma-polyglutamic acid is taken as a starting strain, sodium nitrate is added into a fermentation culture medium, and the activity of polyglutamate synthase is influenced under the nitrate respiration condition by adjusting and controlling the pH value and the ventilation quantity in a fermentation process, so that residual glutamic acid in a fermentation solution is reduced and the conversion rate of glutamic acid is increased; after fermentation, the glutamic acid content of the fermentation solution is 5-15 g/L and the gamma-polyglutamic acid yield is 45-55 g/L. Therefore, the economic and feasible production method is provided for industrialization production of gamma-polyglutamic acid.

The invention provides a preparation method of temperature sensitive hydrogels. The preparation method comprises the following steps: dissolving poly(N-isopropylacrylamide) (PNIPAM) and gamma-polyglutamic acid (gamma-PGA) in distilled water, dissolving by stirring at a room temperature for 1-3 hours, standing overnight at 4 DEG C, and removing bubbles, thus obtaining a uniform aqueous solution; and carrying out water bath at 37 DEG C for 1-8 minutes until the system turns to a milk white gel from a colorless and transparent solution without being dehydrated, wherein the feeding molar ratio of PNIPAM to gamma-PGA ranges from 9: 2 to 7: 6, and the total concentration of the solution is 20%(w/v). The hydrogels prepared by use of the preparation method have temperature sensitivity and also has excellent water absorptivity and water retentivity; the preparation method is simple and time-saving; the preparation method is high in gel forming speed and can be used for preparing temperature sensitive hydrogels different in water absorbency and lower critical solution temperature (LCST) by controlling the feed ratio of PNIPAM to gamma-PGA, and thus is wide in application range. The temperature sensitive hydrogels prepared by use of the preparation method can be applied to drug carriers, wound dressings and the like due to excellent biocompatibility and drug carrying property.

The invention discloses a method for extracting gamma-polyglutamic acid. The scheme of the method comprises the following steps: filtering out thallus by pumping fermentation liquor; adding organic solvent into fermentation supernate, adding sodium chloride, potassium chloride or ammonium sulfate, and putting for one night to obtain precipitate which is a gamma-polyglutamic acid coarse product; dissolving the gamma-polyglutamic acid coarse product into distilled water, filtering out undissolved micromolecule substance in a centrifuging way, adding sodium chloride, potassium chloride or ammonium sulfate and organic solvent into the supernate, stirring to obtain a gamma-polyglutamic acid precipitate, dissolving the gamma-polyglutamic acid precipitate into the distilled water according to 1: (5-10) (m : v), and filtering out impurity by an ultrafiltration membrane; and performing the freeze drying to ultrafiltration peritoneal effluent so as to obtain white gamma-polyglutamic acid powder. After the method is used, the product extraction yield can be effectively improved, the usage amount of the organic solvent can be reduced, the production cost can be lowered, the environment problem caused by a large number of organic solvent during extracting can be avoided, and the environment pollution can be reduced.

The invention discloses a gamma-polyglutamic acid producing bacterium. The gamma-polyglutamic acid producing bacterium is classified and named as Bacillus Subtilis hzy-1, has been deposited in the Chinese Industry Culture Collection Center with the accession number of CCTCC M 2018226 in May 3, 2018. Meanwhile, the invention further discloses a method for efficiently synthesizing gamma-polyglutamicacid. Compared with an existing technology for producing gamma-polyglutamic acid, the method has the advantages that by a used bacillus subtilis strain, the gamma-polyglutamic acid can be effectivelyfermented and produced, the molecular weight of the produced gamma-polyglutamic acid is 1000 KDa or above, by optimization of bacillus subtilis strain culture conditions, the content of the gamma-polyglutamic acid in fermentation liquor reaches 40-60 g/L, and therefore, a method for effectively preparing the gamma-polyglutamic acid at low price is provided. The produced gamma-polyglutamic acid can be applied to the fields of agriculture, cosmetics and the like.

The invention relates to a method for treating acidic fluorine-containing waste water. The method comprises the following steps sequentially: (1) adding calcium-containing substance into the fluorine-containing waste water to be treated and adjusting the pH value of the waste water to be about 4.0 to 9.0; and (2) adding water-soluble gamma-polyglutamic acid serving as a biologic capturing agent into the mixture, fully stirring and standing the mixture, separating the supernatant and collecting the precipitated sludge after the mixture is precipitated and demixed, wherein the calcium-containing substance at least comprises one of calcium hydroxide, calcium oxide or calcium salt. The method overcomes the technical disadvantages in the prior art; the high molecular water-soluble gamma-polyglutamic acid with a molecular weight between 500,000 and 1,500,000 is used in the treatment of the acidic fluorine-containing waste water; and repeated experiments show that the fluorine removing effect is excellent and the treated waste water can meet the national first-class discharge standard; moreover, the method has the advantages of low treatment cost, high efficiency for the treatment process, environment friendliness and no secondary pollution.

Belonging to the field of antibacterial preservatives and food fresh-keeping packaging materials, the invention in particular relates to a nisin/chitosan nano particle antibacterial film, a preparation method and application. Nisin crosslinks with gamma-polyglutamic acid, then chitosan is added to undergo crosslinking with gamma-polyglutamic acid so as to prepare nisin loaded gamma-polyglutamic acid/chitosan nano particles, thus improving the defect of bioactivity decrease of nisin during use and enhancing the utilization rate, then the nisin loaded chitosan nano particles are prepared into an antibacterial film by means of electrospinning so as to reduce the aggregation and drop phenomena of chitosan nano particles during direct sprinkling to food surfaces and avoid bioactivity decrease of encapsulated substances, thereby reaching the purposes of long-acting antibacterial properties and efficient utilization. According to the invention, the operation is simple, by applying the antibacterial film to fresh-keeping of cheese products, growth of pathogenic microorganisms can be effectively inhibited, and the shelf life of products can be prolonged.

The invention discloses bacteria YXY-C1 for preparing gamma-polyglutamic acid by solid fermentation and products thereof, and belongs to the technical field of fermentation of microorganisms. In the invention, a bacterial strain YXY-C1 is used for preparing the gamma-polyglutamic acid efficiently by separation; and by using cow dung and monosodium glutamate meal as main raw materials and bran, corn meal, bean meal, citric acid, MgSO4.7H2O and MnSO4.H2O as auxiliary materials, the bacterial strain YXY-C1 can prepare the gamma-polyglutamic acid by solid fermentation, the yield is 39 grams per kilogram of culture medium, and the molecular weight is 300kD. The bacterial strain YXY-C1 can prepare the gamma-polyglutamic acid by fermenting solid wastes and low-price agricultural and sideline products, and has the advantages of low raw material cost, simple method, high yield, convenient product separation and purification and potential application prospect.