27 results about "Selenious Acid" patented technology

The invention relates to a method for biosynthesizing zero-valent nano-selenium by utilizing pantoea, the method comprises the following steps of: adding selenite into a strain culture medium, culturing pantoea, and separating and purifying from a synthetic product to obtain the zero-valent nano-selenium, the strain name of the pantoea is XZ-1, the classification name is pantoea Pantoeasp., the preservation number is CGMCC No.32330, the collection number is CGMCC No.32330, the collection number is CGMCC No.32330, the collection number is CGMCC No.32330, the collection number is CGMCC No.32330, the collection number is CGMCC No.32330, and the collection number is CGMCC No.32330. The preservation date is October 24, 2024, the strain XZ-1 is applied to synthesize zero-valent nano-selenium, biological nano-selenium is obtained from the synthesized product after multiple times of separation and purification, and the purified biological nano-selenium is mixed with a protective agent and a dispersing agent according to a certain proportion to prepare a nano-selenium fertilizer raw material, so that the problems that the nano-selenium is agglomerated and is easy to oxidize and lose efficacy are solved; the bioavailability of selenium is obviously improved, and the selenium element loss is reduced. The prepared nano-selenium can be used for original ingredients of fertilizers and feeds.

The invention discloses preparation and application of high-stability nano-selenium in a food matrix, the nano-selenium is polysaccharide modified nano-selenium, and the nano-selenium is insensitive to pH and alcohol environment and can keep good stability in a liquid food matrix. According to the scheme, the nano-selenium is prepared by using polysaccharide as a stabilizer and reducing selenite by using ascorbic acid. According to the scheme, the high-performance stabilizer is screened by combining the growth curve of the nano-selenium and the interaction between the nano-selenium and the polysaccharide, the stability mechanism of the screened stabilizer is mainly a steric hindrance effect, the screened stabilizer is not sensitive to the complex environment of a food matrix, agglomeration of the nano-selenium is effectively prevented, and the stability of the nano-selenium in the food matrix is guaranteed. The nano-selenium prepared by the scheme provided by the invention can be used as a novel selenium nutrition enhancer by virtue of high stability, is widely applied to the fields of functional foods and dietary supplements, and provides an optimal scheme for solving the problems of low bioavailability, high potential toxicity and the like of the traditional selenium supplements.

The invention discloses an infinitesimal bio-enzyme fertilizer capable of degrading pesticide residues of crops as well as a preparation method and application of the infinitesimal bio-enzyme fertilizer, and belongs to the technical field of bio-fertilizers. The infinitesimal biological enzyme fertilizer is prepared from the following components in parts by weight: 600 to 700 parts of water, 100 to 150 parts of immobilized beneficial microorganism bacterial material, 80 to 120 parts of activated carbon, 31 to 62 parts of amino acid material, 55 to 65 parts of organic material, 35 to 50 parts of mineral material, 32 to 64 parts of enzyme-containing base material, 1 to 5 parts of vitamin B material, 1 to 2 parts of vitamin C, 5 to 10 parts of acid-base balancing agent, 1 to 2 parts of plant growth regulator and 0.1 to 0.5 part of modified nano-selenium, the modified nano-selenium is prepared from zinc selenite, potassium selenite, sodium selenite and calcium selenite through reduction modification; the immobilized beneficial microbial material is prepared by beneficial microbial fermentation, immobilization and reinforcement. The infinitesimal biological enzyme fertilizer provided by the invention can improve the pesticide degradation rate.

The application discloses a cultivation method for improving selenium content of Auricularia auricula, and comprises a cultivation material for improving selenium content of Auricularia auricula, wherein the cultivation material is obtained by mixing a slow-release sodium chlorate composite material and a slow-release selenium-containing mineral material with carbon nutrition, nitrogen nutrition and mineral nutrition respectively. In the application, the sodium chlorate and selenium are respectively prepared into specific slow-release systems, and the slow-release reaction in the cultivation material generates selenite which is easy to be absorbed and utilized by Auricularia auricula, so that the selenite concentration in the cultivation material is regulated, the growth of Auricularia auricula is promoted, the yield of Auricularia auricula is improved, the quality of Auricularia auricula is significantly improved, the selenium content and the amino acid content of Auricularia auricula are both significantly increased, and the cultivation material can be used for seedling cultivation of Auricularia auricula with high selenium content, so as to obtain high-quality seedlings of Auricularia auricula with high selenium content.

This invention discloses a method for preparing selenized Ophiopogon japonicus polysaccharide, its structural characterization, and its applications. The preparation method includes: dissolving Ophiopogon japonicus polysaccharide in dilute nitric acid, adding sodium selenite, reacting at 50–90°C for 4–12 hours, adjusting the pH to neutral, and obtaining selenized Ophiopogon japonicus polysaccharide after dialysis, concentration, and freeze-drying. Structural characterization was performed using ultraviolet spectroscopy, infrared spectroscopy, and scanning electron microscopy, showing that selenium was successfully linked to the polysaccharide molecule in the form of selenite ester. Multiple cell experiments showed that: CCK-8 assay results indicated that the polysaccharide had no significant toxicity to RAW264.7 cells in the concentration range of 25–100 μg / mL; Griess assay and ELISA results showed that the polysaccharide significantly inhibited LPS-induced release of NO, TNF-α, and IL-6 from macrophages in a concentration-dependent manner; GC-MS analysis of the metabolite lactate revealed its anti-inflammatory mechanism at the metabolic level. Animal experiments showed that the selenized Ophiopogon japonicus polysaccharide significantly reduced the inflammatory response in a mouse skin burn model and promoted wound healing. The process of this invention is simple and the conditions are mild. The selenized Ophiopogon japonicus polysaccharide prepared has good anti-inflammatory activity and can be used to prepare drugs for treating skin burns and inflammation.

The invention relates to the field of agricultural planting, and provides nano-selenium as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, mixing a selenite solution, a polysaccharide solution and an amino acid solution, and carrying out first reaction to obtain a mixed solution; s2, mixing the mixed solution with a reducing agent solution, and carrying out a second reaction to obtain nano-selenium; the molar ratio of selenite in the selenite solution to polysaccharide in the polysaccharide solution is (1-5): 1; the molar ratio of a reducing agent in the reducing agent solution to selenite in the selenite solution is (2-6): 1. When the nano-selenium formed based on the preparation method is applied to crop planting, the selenium enrichment efficiency and the organic selenium conversion efficiency can be remarkably improved, after the nano-selenium is sprayed to crop leaf surfaces, crops can efficiently absorb selenium elements and convert the selenium elements into organic selenium, meanwhile, the effects of reducing cadmium and increasing the yield are achieved, and the selenium content is reduced. A safe and efficient novel selenium fertilizer solution is provided for selenium-rich functional agriculture, and the application prospect is wide.

The invention discloses a selenium element sustained-release tablet and a preparation method thereof, and belongs to the technical field of microelement sustained-release tablet manufacturing. The sustained release tablet is prepared from the following components in percentage by weight: 94.1 to 99.8 percent of calcium sulfate dihydrate, 0.1 to 5.0 percent of nano silicon dioxide and 0.1 to 0.9 percent of sodium selenite. The preparation method of the sustained-release tablet comprises the following steps: uniformly mixing and ball-milling calcium sulfate hemihydrate, nano silicon dioxide and sodium selenite, adding deionized water, stirring, uniformly dispersing and adsorbing selenite ions to the surfaces of calcium sulfate hemihydrate and silicon dioxide particles, injecting slurry into a mold for molding, and drying in an environment with room temperature and relative humidity of 60-90% RH after molding. The sustained release tablet prepared by the invention can slowly and stably release trace element selenium; the preparation process does not need granulation, a pressure forming process, calcination and a low-pressure high-temperature curing process; the prepared sustained release tablet is wide in application, such as a selenium-rich electric cooker, a selenium-rich pressure cooker, a selenium-rich tea cup and the like.

The invention discloses mucoprotein nano-selenium gas motor hydrogel as well as a preparation method and application thereof, and relates to the technical field of biological medicines. The preparation method of the mucoprotein nano-selenium gas motor hydrogel comprises the following steps: adding a carbonyl compound and selenite into an emulsifier solution, and adding a reducing agent for mixing reaction to obtain a nano-selenium gas motor, oxidized mucoprotein and the nano-selenium gas motor are mixed, then a cross-linking agent is added, the oxidized mucoprotein is subjected to a cross-linking reaction to form gel, and the mucoprotein nano-selenium gas motor hydrogel is obtained. The mucoprotein nano-selenium gas motor hydrogel is constructed by wrapping a gas motor into a mucoprotein hydrogel delivery system, the mucoprotein nano-selenium gas motor hydrogel can be specifically delivered to a colitis disease part through rectal administration, and meanwhile, the safe and controllable release and mucous membrane protection effects of the nano-selenium gas motor are realized; therefore, a new thought is provided for treating enteritis.

The present invention provides a pharmaceutical composition containing a selenite-containing compound and a pharmaceutically acceptable acid, selected from citric acid, acetic acid, malic acid, carbonic acid, sulfuric acid, nitric acid, hydrochloric acid, fruit acids and mixtures thereof. This composition is for use in the prevention or treatment of an infection of an internal reproductive organ of a female patient with at least one human papillomavirus (HPV) selected from HPV16, HPV18, HPV31, HPV33 and HPV58. The composition is applied intravaginally.

The invention relates to the technical field of microbiology and selenium polluted environment restoration, and provides an ensifer morelensis R2-120 strain and an application thereof. The bacterial strain R2-120 is ensifer morelensis capable of efficiently synthesizing volatile selenium, and the preservation number of the bacterial strain R2-120 is GDMCC No: 63730. The strain R2-120 has relatively strong tolerance to selenate and selenite, and a plate test shows that the R2-120 can tolerate at least 200 mM of selenate and 60 mM of selenite. The strain R2-120 can metabolize selenite and convert the selenite into nano-selenium, and can convert the selenite and the nano-selenium into volatile selenium. The invention also establishes a method for removing selenium in the water body by using R2-120 in the bioreactor, and the method can be used for bioremediation of selenium-polluted water body and soil, treatment of selenium-containing wastewater and recycling of selenium, and has a wide application prospect.

The present application relates to a kind of electrolytic manganese plate pre-electrolysis-pole replacement collaborative treatment process, after stripping manganese washing, cathode plate is sent into pre-electrolysis tank pre-electrolysis;Pre-electrolysis tank is equipped with pre-electrolyte, when pre-electrolysis, the concentration of selenious acid ion in pre-electrolyte, the concentration of selenious acid ion, the electrolytic temperature of pre-electrolyte, the pH of pre-electrolyte, manganese ion concentration;After processing, cathode plate is removed from pre-electrolysis tank, and is sent to main electrolysis tank and is electrolytic deposition, main electrolysis tank is equipped with main electrolyte, and when electrolytic deposition, the electrolytic temperature of main electrolyte, manganese ion concentration, pH is controlled, and is repeatedly.The present application also discloses a kind of electrolytic manganese plate pre-electrolysis-pole replacement collaborative treatment process with electrolytic manganese production system.In the present application, the "manual adjustment warehouse" link in main tank can be completely cancelled, the edge effect of pole plate and the uneven current density caused by frequent current rise and fall are avoided, and the risk of burst plate caused thereby is fundamentally eliminated.

The invention discloses soil sporosarcina CH23 as well as a method for synthesizing nano-selenium by using the soil sporosarcina CH23 and application of the soil sporosarcina CH23. The nano-selenium synthetic bacterium is sporosarcina soli CH23, is preserved in the Guangdong Microbial Culture Collection Center (GDMCC), and has the preservation number of GDMCC No.67015. The invention further discloses a preparation method of the nano-selenium synthetic bacterium. The soil sporosarcina CH23 can be used for efficiently converting high-toxicity selenite into non-toxic nano-selenium. The required culture conditions are simple, the cost is low, and the operation is easy. The produced nano-selenium particles have the advantages of being non-toxic, high in biological activity, stable in property, almost free of other selenium by-products and the like, have the effects of resisting bacteria, resisting oxidation, resisting cancers and the like in the field of medicines, can also be used as a nano-selenium fertilizer for plant selenium nutrition supplement, and have the advantages of being more efficient, safer and more environmentally friendly compared with a traditional selenite selenium fertilizer.

The invention relates to the technical field of microbiology and biological nano-selenium preparation, and provides a sphingomyza sp. R3-92 strain and application of the sphingomyza sp. R3-92 strain. The strain R3-92 is a new strain of sphingomyza sp capable of efficiently converting selenite into nano-selenium, the new strain is planned to be named as selenium reduction sphingomyza sp, and the preservation number of the new strain is GDMCC No: 63729. The strain R3-92 is a new strain of sphingomyza sp, is planned to be named as selenium reduction sphingomyza sp, and is named as selenium reduction sphingomyza sp. The strain R3-92 has relatively strong tolerance to selenate and selenite, and a plate culture test shows that the R3-92 can tolerate 100 mM of selenate and 80 mM of selenite. The invention also establishes a method for preparing a large amount of nano-selenium by using R3-92 in a bioreactor, and the method has obvious application effects in fertilizer, feed, selenium-rich functional food processing, health care products and medical products.

This invention provides a nano-selenium, its preparation method, and its applications, relating to the field of nano-selenium fertilizer technology. Using sodium selenate or sodium selenite as raw material A and thiol-functionalized graphene as raw material B, raw material A and raw material B are mixed and reacted for a certain period to obtain nano-selenium, which can be used in fertilizers, food anti-oxidation and preservation, industrial catalysis, or chemical analysis. This invention uses inorganic selenium and thiol-functionalized graphene as raw materials. Through a simple solution mixing, reaction, and settling process, the in-situ reduction of selenite by thiol-functionalized graphene and the stable loading of nano-selenium are achieved, completing the conversion from inorganic selenium to nano-selenium in one step without the need for reducing agents.

The invention discloses a plant organic selenium supplement and a preparation method and application thereof, and belongs to the technical field of selenium-rich agricultural product planting. The plant organic selenium supplement is prepared by the following steps: heating seleninic acid and honey in an aqueous solution to react for 0.5-2 hours, adding an alkali solution to adjust the pH value to be neutral, and adding purified water to dilute. The plant organic selenium supplement is dissolved in water for dilution, uniformly stirred and sprayed on the rape after 2 months, so that the selenium content in the rape moss can reach more than 200mu g / kg, and the harm caused by inorganic selenium residue can be avoided. The method has practical significance for promoting the development of selenium-rich agricultural products.

The present invention discloses a bifunctional catalyst of iron selenide / carbon-based material and a preparation method thereof. In the method, ferric chloride and 2-aminoterephthalic acid are ultrasonically dissolved in DMF, and after a mixing reaction, a sodium hydroxide solution is added, and a hydrothermal reaction is carried out to obtain a dispersion liquid of NH2-MIL-88B(Fe) precursor, and then a selenious acid solution is added, and a stirring reaction is carried out to obtain NH2-MIL-88B(Fe)-SeO3 2‑ polymer precursor. Finally, under a protective atmosphere, the polymer precursor is calcined to obtain an FeSe x / Fe2O3@C bifunctional catalyst. The bifunctional catalyst of the present invention is composed of iron oxide wrapped by carbon and a heterostructure of iron triselenide / iron selenide formed by carbonization, and can be used as an efficient oxygen reduction functional catalyst, having excellent catalytic performance and electrochemical durability, with a starting potential of 0.928 V, a half-wave potential of 0.770 V and a limiting current density of 5.30 mA cm ‑2 The limiting current density is better than that of commercial Pt / C in performance.

The invention discloses a composition for increasing the selenium content in liquiritin, glycyrrhiza polysaccharide and liquorice and application of the composition. The technical problem to be solved by the invention is how to increase the content of selenium and active substances in liquorice. To this end, the present invention provides a composition containing a rhizobium and a selenite, the rhizobium being a mesorhizium temperulum 01578 (i.e., a mesorhizium temperulum CCBAU 01578), and a method for producing the same, and the present invention provides a composition containing the rhizobium, i.e., a mesorhizium temperulum CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU CCBAU. Experiments prove that when the rhizobium and exogenous selenium are jointly applied, the content of liquiritin, glycyrrhiza polysaccharide, selenium, fat, protein, flavone, saponin and / or glycyrrhizic acid in liquorice can be effectively increased, and a reference basis is provided for increasing the medicinal value of liquorice and the like.

The invention discloses an application of Burkholderia stabilizing bacteria in preparation of nano-selenium. According to the invention, the red nano-selenium is prepared by stabilizing a Burkholderia BX1 strain and carrying out biosynthesis. The invention discloses that the BX1 strain has selenite reducing capacity and can tolerate selenite with high concentration; the strain can efficiently convert sodium selenite to generate nano-selenium, the conversion rate is high, the conversion rate is high, 85.5% of sodium selenite can be converted within 2 hours, and the synthesized nano-selenium particles are uniform. And the content of the nano-selenium obtained by conversion in a liquid culture medium containing 5 mM of sodium selenite is 351.22 mg / kg. Meanwhile, the biosynthesized nano-selenium has a very good control effect on tobacco diseases, and the control effect on tobacco sclerotium rolfsii reaches 76.47%. The preparation method of biosynthetic nano-selenium provided by the invention is simple and convenient, high in efficiency, low in cost, high in product purity and environment-friendly, and provides more microbial strain resources for biosynthetic nano-selenium.

The application discloses soil sporosarcina CH23 and a method and application of synthesizing nano selenium by using the soil sporosarcina. Sporosarcina soli The nano selenium synthesis bacteria are soil sporosarcina (Sporosarcina siccitae) CH23, which are preserved in a Guangdong Microbial Culture Collection Center (GDMCC) and have a preservation number of GDMCC No. 67015. The soil sporosarcina CH23 can efficiently convert high-toxicity selenite into non-toxic nano selenium. The required culture condition is simple, low in cost and easy to operate. The produced nano selenium particles have the advantages of non-toxicity, high biological activity, stable property and almost no other selenium byproducts, and have the effects of antibiosis, antioxidation and anticancer in the medical field. In addition, the nano selenium can be used as a nano selenium fertilizer for plant selenium nutrition supplement, and has the advantages of higher efficiency, safety and environmental protection compared with traditional selenite selenium fertilizer.

The invention relates to the technical field of alopecia treatment, and discloses an exosome mixture for treating alopecia, which comprises: (a) exosome from gene edited hair follicle progenitor cells; (b) nano-selenium particles; and (c) a pH and glutathione dual responsive mineralization layer coated on the surface of the exosome, the gene-edited hair follicle progenitor cell overexpresses miR-25-5p and miR-205 through a CRISPR / Cas9 technology, and integrates a Wnt3a gene to a regulation region of exosome membrane protein CD63, and the mineralization layer is composed of calcium phosphate and selenite. According to the invention, a scheme of combining a gene editing exosome compound and nano-selenium is adopted, so that synchronous activation of three channels of regeneration promotion, anti-inflammation and anti-apoptosis of hair follicles is realized, the beta-catenin signal intensity is improved, the growth period of the hair follicles is prolonged, and the bottleneck of the curative effect of the traditional therapy is broken through.

The invention relates to the technical field of biological pharmacy, and discloses an O-glycan preparation targeting oral and gastric mucosa. The invention relates to a preparation method of an O-glycan preparation targeting oral and gastric mucosa, which comprises the following steps: 1) dissolving O-glycan and seleninic acid in water to obtain a mixed solution, then adding a catalytic amount of barium chloride into the mixed solution, and reacting to obtain selenized O-glycan; (2) mixing the selenized O-glycan obtained in the step (1) with methoxy heptapolyethylene glycol carboxyl, and crosslinking to obtain a selenized O-glycan-methoxy heptapolyethylene glycol carboxyl dimer; and 3) dropwise adding the selenized O-glycan-methoxy heptapolyethylene glycol carboxyl dimer obtained in the step 2) into a chitosan solution, and standing to obtain the O-glycan preparation targeting the oral cavity and the gastric mucosa. The O-glycan preparation for targeting the oral mucosa and the gastric mucosa, provided by the invention, can target the oral mucosa and the gastric mucosa, and has a better inhibition effect on helicobacter pylori.

The present invention relates to the technical field of agricultural production, and specifically relates to a multi-functional cadmium-reducing and selenium-enriching stabilization material, its preparation method and application. The present invention uses milk vetch as an organic raw material, combines the selenium-enriching additive sodium selenite and cadmium stabilization materials such as potassium sulfide, diammonium hydrogen phosphate, and quicklime to prepare a multi-functional cadmium-reducing and selenium-enriching stabilization material. The present invention combines milk vetch with a variety of cadmium-reducing and selenium-enriching additives, which can not only ensure the nutrient components (N, P, K, S) required for crop growth, but also significantly improve the effect of cadmium reduction and selenium enrichment in crops, which is conducive to achieving the goal of cadmium reduction and selenium enrichment efficiently and quickly.

The present invention discloses a method for preparing a multi-layered black phosphorus, molybdenum selenide, and graphene battery anode material. The method involves ultrasonically exfoliating black phosphorus blocks in a pre-prepared hydrazine hydrate aqueous solution. A certain amount of the black phosphorus suspension is then drawn, selenious acid and sodium molybdate are added, and the mixture is stirred for a certain period before undergoing a hydrothermal reaction to form a black phosphorus and molybdenum selenide composite. The prepared black phosphorus, molybdenum selenide, and graphene are then ultrasonically dispersed in anhydrous ethanol, mixed and stirred uniformly, and then reduced with a certain amount of hydrazine hydrate dropwise, thereby obtaining a multi-layered black phosphorus, molybdenum selenide, and graphene composite material. The method utilizes a hydrazine hydrate-pretreated aqueous solution as the stripping solvent, facilitating post-processing while avoiding the use of toxic, hazardous, and expensive organic solvents. The resulting black phosphorus, molybdenum selenide, and graphene material exhibits excellent electrochemical performance, which is of great significance for the development of black phosphorus-based potassium ion anode materials.

The application discloses a Leuconostoc citreum and application of the Leuconostoc citreum in preparation of nano selenium, and relates to the technical field of selenium-rich bacterial strain screening and cultivation. The Leuconostoc citreum provided by the application is preserved in the China Center for Type Culture Collection on September 29, 2024, and the preservation number is CCTCC NO: M 20242123, and the preservation address is Luojia Mountain, Baying Road, Wuchang District, Wuhan City, Hubei Province. The Leuconostoc citreum has good tolerance to selenite and the ability to reduce selenite to generate nano elemental selenium; the strain also has good antibacterial effect, especially on gram-negative bacteria; and the strain has good acid and bile salt tolerance, and also has a high survival rate in the gastrointestinal tract.

The invention discloses a method for synthesizing nano-selenium by high-density fermentation of saccharomyces cerevisiae boulardii, a selenium-enriched yeast product prepared by the method and application of the nano-selenium in tomato cultivation. The fermentation comprises three-stage seed propagation (at 30-32 DEG C, 250-300 rpm, and inoculation amount of 5-10%), inoculation (dissolved oxygen is greater than or equal to 30%), supplementary feeding (residual sugar is 2-5 g / L), selenite induction (1-3 mM until the fermentation broth is brick red) and final-stage temperature and pH regulation, and the selenium-enriched yeast with the cell dry weight of 150-300 g / L and the dry basis organic selenium of 6900-7500 mu g / g is obtained. During application, tomato is sprayed for the first time in 45 days after transplanting and is sprayed for three times (accumulated spraying liquid is 3.2-3.6 L / group) in 14 days, the optimal dosage is 10mg / L, the TA liter of tomatoes is more than or equal to 80%, the dry weight liter is more than or equal to 8%, the sugar-acid ratio is 3.8-4.5, and the selenium content of fruits exceeds that of a control group by 85% and is superior to that of sodium selenite; the dosage of 20mg / L is easy to generate growth inhibition, and the dosage is not used as a recommended application concentration; the method is safe and efficient, and is suitable for industrialization and agricultural popularization.

The invention provides a selenium fertilizer formula and an application method, the formula comprises selenite, citric acid, nano silica gel, humic acid-chitosan and other components, and stable loading and pH response release of selenium element are realized through a three-stage chelating system. The citric acid and Se < 4 + > form a [SeO3.C6H5O7] < 3-> complex, the nano silica gel (with the aperture of 3 nm) is used for physical adsorption, and the humic acid-chitosan film is swelled and released when the pH value is 6.5. Polyglutamic acid inhibits selenium-iron antagonism, and ammonium molybdate activates selenite reductase. Soil basal application and foliage spraying are combined, so that the selenium absorption rate of rice is increased to 78.3%, the selenium methionine proportion of tomatoes is 67.2%, and the selenium distribution uniformity (CV value is 12.3%) of citrus is improved. Proportionally, the invention verifies the significant advantages in stability, bio-availability and slow release characteristic.

The invention relates to the technical field of fertilizers, in particular to selenium-doped diatom biochar, a nano-selenium fertilizer and a preparation method and application of the selenium-doped diatom biochar and the nano-selenium fertilizer, selenium in the selenium-doped diatom biochar exists in the form of nano-selenium, the size of the nano-selenium is about 100-150 nm, the content of the nano-selenium is not lower than 15 micrograms per 100 grams, and the content of the nano-selenium is not lower than 10 micrograms per 100 grams. According to the structure, nano-selenium dots are embedded in the surface and the interior of biochar. The diatom is used for reducing nano-selenium, the method is not limited to existing high-reducing-property bacteria for reducing selenite, and the method has higher universality and economical efficiency.