510 results about "Liquid culture" patented technology

The invention relates to the technical field of microorganisms and particularly discloses bacillus velezensis for producing tetramethylpyrazine and application of the bacillus velezensis, the preservation number of the strain is CCTCC NO: M20232058, and the bacillus velezensis is obtained by separating and purifying from high-temperature Daqu of Maotai-flavor liquor in the liquor industry of Jin-brand Maotai Town in Guizhou. The bacillus velezensis disclosed by the invention can produce 1875.4 mg / L of tetramethylpyrazine by performing shake flask fermentation on a liquid culture medium for 7 days, and the tetramethylpyrazine can reach 4810.8 mg / L by optimizing a culture medium formula and culture conditions. The bacillus velezensis is applied to small-scale brewing of Maotai-flavor liquor, the content of tetramethylpyrazine in the Maotai-flavor liquor reaches 34.5 + / -1.4 mg / L and is increased by 325.93% compared with a contrast, and the bacillus velezensis can be used for increasing the content of tetramethylpyrazine in the Maotai-flavor liquor.

A method for enhancing hydrogen uptake by cells of an acetogenic bacterium in a culture is provided. The method comprises incubating the cells in a liquid medium supplemented with an external gas mixture, wherein the external gas mixture comprises H2 and CO2; overexpressing an uptake hydrogenase and an associated electron transfer protein in the cells; increasing uptake of the H2 by the cells; and enhancing uptake of the CO2 by the cells. The culture may be a coculture with additional cells of a non-acetogenic bacterium, which produces natively H2 from catabolism of an organic molecule.

The invention discloses a fermentation method of recombinant bacillus subtilis for expressing vibrio parahaemolyticus outer membrane protein, which comprises the following steps: inoculating a recombinant bacillus subtilis strain into a liquid culture medium for activation and amplification to obtain a seed solution; transferring the seed solution into a fermentation tank according to the inoculum size of 5%-10%, controlling the temperature to be 35-37 DEG C and the pH to be 6.8-7.2, introducing sterile air and stirring, and monitoring the thallus concentration OD600 value in real time; when the OD600 value reaches 35-38, 10% of an inducer is added for pre-induction; when the OD600 value reaches 40-45, the remaining 90% of the inducer is added for main induction, and the real-time dissolved oxygen value is collected; when the real-time dissolved oxygen value is continuously higher than a first preset threshold value, the flow acceleration rate of the inducer is increased, the fermentation temperature is increased at the same time or step by step, and the increase amplitude of the dissolved oxygen value is in positive correlation with the flow acceleration rate and the temperature increase amplitude; when the OD600 value is stabilized in a preset interval, it is judged that fermentation is completed, and the recombinant bacillus subtilis thalli are obtained. The yield and quality of the vibrio parahaemolyticus outer membrane protein can be effectively improved.

The invention belongs to the technical field of preparation of probiotic products, and relates to a lactic acid bacteria microcapsule as well as a preparation method and application thereof. The method comprises the following steps: uniformly mixing sodium alginate, modified montmorillonite and sterile water, cooling, adding a prepared lactic acid bacteria seed solution, and fully and uniformly mixing to form an emulsion; spraying the emulsion into a calcium chloride solution by adopting an extrusion method, stirring and curing to obtain microcapsules; and culturing the prepared microcapsule in a lactic acid bacteria liquid culture medium to obtain the lactic acid bacteria microcapsule after the culture is finished. The lactobacillus is effectively protected by adopting an extrusion-method single coating and post-coating culture process, so that the stability of the lactobacillus to a humid and hot environment and the gastrointestinal stress resistance are improved, and meanwhile, the release performance of the lactobacillus in the gastrointestinal tract is ensured. The problem that an existing microcapsule coating technology cannot achieve balance between improvement of the hygrothermal stability and gastrointestinal stress resistance of the probiotics and guarantee of good release performance of the probiotics in the gastrointestinal tract is solved.

The invention belongs to the technical field of microorganisms and fermentation engineering, and particularly relates to application of bifidobacterium longum subsp. Infantis Y46 in the aspects of enhancing cell defense and repair and regulating metabolic homeostasis of a host. The strain is isolated from infant feces. Animal experiments prove that living cell thalli of the bifidobacterium longum subsp. Infantis Y46, which are obtained by culturing an MRS liquid culture medium added with L-cysteine hydrochloride (0.05%, v / v), can significantly enhance the oxidative stress resistance of an organism and reduce the level of active oxygen in the organism compared with a control bacterium bifidobacterium longum subsp. Infantis 15697. Transcriptomics analysis shows that the bifidobacterium longum subsp. Infantis Y46 can enhance self-protection of cells and improve physiological imbalance caused by external pressure by regulating related signal channels of an organism. The action mechanism is closely related to signaling pathways related to cell defense, metabolic homeostasis and barrier functions. The invention provides a new strain resource and an application scheme for developing functional food or medicinal preparations for enhancing the health defense function of a human body.

The invention belongs to the technical field of microorganisms and fermentation engineering, and particularly relates to application of bifidobacterium longum subsp. Infantis Y46 in the anti-aging aspect. The bifidobacterium longum subsp. Infantis Y46 is obtained from excrement of infants. Animal experiments prove that living cell thalli (Y46) and thermally inactivated cell thalli (HKY46) obtained by culturing the bifidobacterium longum subsp. Infantis Y46 by using an MRS liquid culture medium containing L-cysteine hydrochloride (0.05%, v / v) can significantly reduce accumulation of lipofuscin in a host, and prolong the healthy life and life of the host. Therefore, the bifidobacterium longum subsp. Infantis Y46 is a promising probiotic and a promising metagen with an anti-aging function.

The invention belongs to the technical field of genetic engineering of edible mushrooms, and particularly relates to a construction method of an efficient and stable genetic transformation system of flammulina velutipes. The construction method comprises the following steps: culturing in an MM culture medium by taking a flammulina velutipes strain 0747 as a receptor; the pFgnpt vector is converted into agrobacterium AGL1 (AGL1); inoculating hyphae into an IM liquid culture medium containing acetosyringone and MES, mixing with agrobacterium tumefaciens, culturing, and transferring the hyphae to an IM solid flat plate paved with filter paper; hyphae are transferred to a PDA resistance plate containing G418 and cephalosporin for resistance screening, and an efficient and stable flammulina velutipes genetic transformation system is obtained. The new selection marker G418 is developed and applied, limitation of a traditional selection marker is broken, more choices are provided for flammulina velutipes genetic transformation, a new thought is provided for genetic transformation research of other edible mushrooms, and the application field of an agrobacterium tumefaciens-mediated transformation technology is expanded.

The invention discloses 3D printing high-light-transmittance bio-ink, an artificial 3D algal-bacterial symbiont and a preparation method and application of the artificial 3D algal-bacterial symbiont. The 3D printing high-light-transmittance bio-ink is prepared from polyether F127 diacrylate, polyethylene glycol diacrylate, pyridine degradation special-effect bacterium paracoccus sp. NJUST47, chlorella sorokiniana FACHB-275, a light absorbent and a liquid culture medium containing a photoinitiator, and the 3D printing high-light-transmittance bio-ink is prepared into an artificial 3D bacterium-algae symbiont through one-step 3D printing. The 3D printing high-light-transmittance bio-ink has good synergistic pyridine degradation performance, the constructed artificial 3D algal-bacterial symbiont has high algal-bacterial loading capacity and excellent light utilization rate, enhanced removal of volatile toxic organic pollutant pyridine can be achieved, and degradation stability is good.

The invention discloses a biological challenge device with combined adjustable resistance for evaluating the effect of a sterilization process, which comprises a shell, the shell comprises a plastic pipe and an inner pipe cap detachably connected with the inner wall of the plastic pipe, the inner pipe cap is provided with a breathable window and covered by a breathable film, and a bacterial contamination carrier for bearing indicator biological spores is attached to the inner bottom of the plastic pipe. An openable container containing a liquid culture medium is arranged in the plastic pipe cavity; the outer side of the inner pipe cap is sleeved with an outer pipe cap detachably connected with the outer wall of the plastic pipe, and the outer pipe cap is provided with a flow blocking structure used for adjusting the speed of the sterilizing agent entering the area of the inner pipe cap; the indicator biological spores are pretreated by a stable protective agent containing one or more of polyethylene glycol, trehalose, sorbitol, polyvinylpyrrolidone and glyceryl stearate. The speed of a sterilizing agent entering the device can be limited, the spores are dry in a suspension added with a stable protective agent, the capability of resisting general environmental changes is very good, and the performance of the device can be maintained for a long time.

The invention belongs to the technical field of fungal fermentation, and particularly discloses ganoderma lucidum fermentation liquor and a preparation method thereof. The preparation method of the ganoderma lucidum fermentation liquor comprises the following steps: (1) activating a strain, namely inoculating the strain into a slant culture medium for culturing, and carrying out transfer grafting once to obtain an activated strain; (2) liquid culture: inoculating the activated strain into a liquid culture medium, and carrying out shake culture for 7 days to obtain a liquid strain; (3) fermentation culture: inoculating the liquid strain into a fermentation culture medium according to the inoculation amount of 7-9%, and carrying out three-stage culture to obtain a fermented product; and (4) centrifugal filtration: centrifuging the fermented product, collecting a supernatant, and filtering the obtained supernatant to obtain the ganoderma lucidum fermentation broth. According to the preparation method disclosed by the invention, three-stage variable-condition culture is specifically carried out according to the growth condition of the ganoderma lucidum mycelia, so that rapid growth of the ganoderma lucidum mycelia and mass accumulation of polysaccharides are facilitated, and the polysaccharide content of the prepared ganoderma lucidum fermentation liquor is increased.

The invention discloses a method for quickly and efficiently differentiating iPSC (induced pluripotent stem cells) into mesenchymal stem cells in a serum-free manner, the method comprises the following steps: firstly inducing the iPSC into a mesoderm precursor, then transferring the mesoderm precursor into a liquid culture medium for suspension culture, and finally obtaining iMSC (iPSC-doped MSC) by using an enrichment culture medium, and the method can shorten the differentiation time, improve the purity of the iMSC and obtain a large number of homogenized iMSCs.

The invention discloses a high-yield flower and fruit aroma strain, culture thereof and application of the high-yield flower and fruit aroma strain in sauce-flavor food brewing, the strain is named as Wickerhamomyces anomalus GZZJ2023Y053, and is preserved in the China Center for Type Culture Collection (CCTCC) with the preservation number of CCTCC NO: M 2025875, and the preservation number of the strain is CCTCC NO: M 2025875. The preservation date is April 24, 2025; the preservation address is Wuhan University, Wuhan, China. The culture method of Wickerhamomyces anomalus comprises the following steps: inoculating activated Wickerhamomyces anomalus GZZJ2023Y053 into a liquid culture medium, and fermenting at constant temperature to obtain a seed solution; the invention also provides an application of the Wickerhamomyces anomalus GZZJ2023Y053 in preparation of ethyl acetate and brewing of sauce-flavor foods. According to the method, multiple Wickerhamomyces anomalus separated from fermented grains is subjected to separation culture, the content of ethyl acetate is measured after fermentation is finished, then the screened Wickerhamomyces anomalus GZZJ2023Y053 has the capacity of producing ethyl acetate at high yield, and after fermentation conditions are further optimized, the yield of the ethyl acetate is improved. The capability of synthesizing ethyl acetate is greatly improved.

The invention discloses an expression system suitable for short-chain non-specific peroxidase and application of the expression system, and belongs to the technical field of enzyme engineering and genetic engineering. According to the expression system disclosed by the invention, a nucleotide sequence of short-chain non-specific peroxidase with SUMO and 8HIS tags is connected to a pET28a vector to obtain a recombinant vector, and escherichia coli BL21 (DE3) is transformed to obtain a genetically engineered bacterium; genetically engineered bacteria are subjected to two-stage temperature control culture in a ZYM5052 liquid culture medium, and meanwhile, 5ALA is added into the culture medium. According to the invention, an escherichia coli self-induction system is used, so that a shake-flask culture can grow at high density in a short time, the culture medium contains rich nutrient substances, and monitoring of cell density and adding of IPTG are not needed in the expression process. Meanwhile, a heme precursor 5ALA is added into an escherichia coli self-induction culture medium, and finally the high-activity short-chain non-specific peroxidase is obtained.

The utility model belongs to the technical field of plant tissue culture devices, and particularly relates to a plant tissue culture device which comprises a tray, a plurality of plant tissue culture devices and a plurality of plant tissue culture devices, the tray comprises a supporting frame and a hole tray, and the hole tray is placed on the supporting frame and provided with a plurality of circular hole grooves; the tissue culture bag is placed in the hole groove and comprises a bag body, the section of the bag body is circular, the diameter of the bag body is gradually increased from bottom to top, a hard ring is arranged at the top of the bag body, a groove is formed in the bottom of the hard ring, at least three hanging lugs are arranged on the outer wall of the hard ring, and air holes are formed in the bag body; provided is a tissue culture frame. The tissue culture bag is small in bottom area and large in top opening area, and the inoculation area is increased under the condition that the same amount of culture medium is injected; the circular bottom design ensures that the culture medium can be upright without falling after being solidified; the cylindrical bag body is designed, so that the tissue culture bag is not easy to collapse; the tissue culture frame can maintain the shape of the tissue culture bag body not to be deformed, and a liquid culture medium can be conveniently and rapidly canned in production.

The utility model relates to a tremella liquid strain inoculation device which comprises a rack, a conveying roller mechanism used for transversely conveying a culture bottle tray is arranged on the rack, a first station and a second station are sequentially arranged on the conveying roller mechanism in the conveying direction, a first blocking mechanism used for blocking the tray is arranged on the first station, and a second blocking mechanism used for blocking the tray is arranged on the second station. A drilling mechanism which can ascend and descend and is used for enabling a culture medium in the culture bottle to form a concave hole is arranged above the first station, a second blocking mechanism which is used for blocking the tray is arranged on the second station, and a bacterium injection mechanism which can ascend and descend and is used for injecting a liquid strain into the concave hole of the culture medium is arranged above the second station. The device is compact in structure, inoculation of liquid strains in the tremella culture bottle can be conveniently achieved, and the liquid strains can enter a culture medium more quickly.

The invention provides a grifola frondosa liquid culture medium as well as a culture method and application thereof, and relates to the technical field of fermentation. The invention provides a grifola frondosa liquid culture medium, which contains glucose, peptone, KH2P2O4, MgSO4, vitamin B1, gibberellin and tyrosol, can significantly improve the growth of grifola frondosa thalli and the secretion of exopolysaccharides, and can be used for the preparation of food, drugs and health care products.

The invention discloses a marine fungus fusarium keratinoides and application thereof. The fusarium keratinoides capable of efficiently producing the perindoprine is screened from marine sediments, and the content of the produced perindoprine can reach 561.7 mu g / L after the fusarium keratinoides is fermented in a GPY liquid culture medium, so that possibility and a foundation are provided for breeding strains suitable for industrial large-scale production of the perindoprine in the future; mass spectrum, hydrogen spectrum and carbon spectrum data of the separated perindoprine are completely consistent with perindoprine data reported in literatures.

The invention discloses a liquid strain culture device and culture method for black skin termitomyces albuminosus, and relates to the technical field of strain culture, the liquid strain culture device comprises a supporting assembly, a light reflecting assembly and a liquid supplementing assembly, the supporting assembly comprises four supporting columns, the outer surface of one supporting column is fixedly connected with a mounting plate, and the outer surface of the other supporting column is fixedly connected with a fixing plate; and a controller and an electronic timer are arranged on the outer surface of the mounting plate. The illumination mode of light supplement is adjusted through monitoring of an electronic timer, meanwhile, an illumination sensor detects the illumination degree received by liquid strains in each area, an electric push rod is controlled to be started through a controller, the electric push rod is made to stretch out and draw back, the angle of a light reflecting plate is adjusted, and the light supplementing effect is improved. Therefore, the light reflecting surface can reflect outdoor light or outdoor lamplight to the liquid strain culture area to supplement light for the liquid strain culture area.

The invention relates to the technical field of mycelium culture, and provides a culture method and application of cordyceps militaris mycelium with high selenium content and high cordycepin content. The culture method comprises the following steps: inoculating cordyceps militaris mycelia into a liquid culture medium, and carrying out shake culture for 4-7 days to obtain cordyceps militaris liquid seeds; adding a plant selenium source into the solid culture medium, sterilizing to obtain a cordyceps militaris selenium-rich solid culture medium, adding the cordyceps militaris liquid seeds into the cordyceps militaris selenium-rich solid culture medium, and continuously culturing for 30-40 days to obtain the high-selenium and high-cordycepin cordyceps militaris mycelium. According to the culture method, the steps are simple and convenient, the raw materials are cheap and safe, the total selenium content of the produced mycelium is 0.76-191.45 mg / kg, the organic selenium content is more than 99%, the cordycepin content is 17707.3-24769 mg / kg, the content of various effective components such as the total selenium, the organic selenium and the cordycepin is outstanding, the yield is high, standardized popularization and application of the selenium industry in multiple fields are facilitated, and the wide market prospect is achieved.

The invention relates to a fungus-diatom synergistic immunopotentiator for stichopus japonicus, and belongs to the technical field of microbial engineering and echinoderm immunology. The immunopotentiator is a symbiont microsphere taking yarrowia lipolytica and navicula seminuda as main components; the method comprises the following steps: respectively activating yarrowia lipolytica and navicula seminuda, carrying out expanding culture, resuspending, and adjusting the concentrations of a bacterial solution and algae cells; the preparation method comprises the following steps: adding a navicula seminuda concentrated solution and a yarrowia lipolytica suspension into a triangular flask containing a YPD liquid culture medium, adding selenium-containing fucoidan polysaccharide sulfate accounting for 0.4-1.2% of the total mass of microspheres, carrying out constant-temperature shake culture, filtering by using sterile gauze to obtain microspheres, and flushing by using sterile normal saline to obtain fungus-diatom symbiont microspheres; the yarrowia lipolytica, the navicula seminuda and the selenium-containing fucoidan polysaccharide sulfate in the prepared immunopotentiator are mutually beneficial and have a synergistic effect, and the non-specific immune function of the stichopus japonicus is comprehensively improved by improving the growth index, enhancing the activity of immune enzyme and digestive enzyme and improving the disease resistance.

The invention provides Saccharomyces cerevisiae for producing squalene as well as a screening method and application of the Saccharomyces cerevisiae. The method comprises the following steps: culturing a Saccharomyces cerevisiae engineering strain ySC782 for synthesizing squalene to obtain a to-be-mutagenized bacterial solution, carrying out ARTP mutagenesis on the to-be-mutagenized bacterial solution, adding the to-be-mutagenized bacterial solution into a YPD liquid culture medium, culturing to obtain a resuscitation bacterial solution, adding the resuscitation bacterial solution into a sucrose solution with gradient concentration distribution, screening, and repeating the ARTP mutagenesis-sucrose solution screening step to obtain the squalene mutant strain. And finally, the saccharomyces cerevisiae strain ySC782-M5 is obtained through screening, and the saccharomyces cerevisiae strain ySC782-M5 is obtained through screening. The yield of squalene produced by the saccharomyces cerevisiae ySC782-M5 reaches 49.83 g / L, so that a solution is provided for breaking through the yield bottleneck of squalene synthesized by yeast.

It comprises a receptacle for the culture of plant material, a cap for closing an opening to said receptacle, and means for allowing the entry and / or exit of gas from said receptacle, and is characterized in that it comprises a container for receiving a liquid culture medium inside the receptacle, and support means for supporting the plant material on said reception container, wherein said container is attached to the lid of the receptacle in a position suitable for use, said lid including at least one medium inlet and / or exit conduit that connects with the container to be able to fill and / or empty said container through said conduit.

The invention relates to the field of microorganism screening, in particular to a microorganism screening method capable of improving saline-alkali soil crop stress resistance and application thereof.The microorganism screening method comprises the following steps that S1, in saline-alkali soil with Na < + > larger than 0.6% and pH 8.5-10.0, suaeda glauca rhizosphere soil and root system tissue are collected and inoculated to 0.6 moL / L NaCl, and the saline-alkali soil is inoculated to a culture medium; in a liquid culture medium with the pH value of 8.0, through a gradient saline-alkaline stress enrichment-bifunctional bacterium collaborative screening technology and in combination with an embedding matrix and modified biochar compounded microbial screening agent, compared with the prior art, salt ion adsorption, flora survival rate improvement, root system nitrogen fixation and phosphate solubilizing bacterium standard-reaching rate improvement and crop biomass increase are synchronously realized, and the yield of the crops is increased. And moreover, the toxicity of salt ions is remarkably reduced, the soil micro-ecology is systematically optimized, and the method has a wide application prospect in marginal land agricultural development and saline-alkali soil ecological restoration.

The invention belongs to the technical field of microorganisms, and particularly discloses high-activity lactic acid bacteria powder as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out activation culture on lactic acid bacteria in a liquid culture medium to obtain an activated bacteria solution; adjusting the concentration of the activated bacterial liquid, standing and incubating, and in the incubation process, dynamically measuring the formation amount of a biological membrane by adopting a crystal violet staining method, and determining the optimal biological membrane incubation time of the lactic acid bacteria strain; adjusting the concentration of the activated bacterial liquid, standing and incubating to the determined optimal biological membrane incubation time; washing off thalli which are not adhered to the upper layer by using the sterile PBS, and centrifugally collecting biofilm state lactic acid bacteria which are adhered to the bottom of the culture container; and re-suspending the collected biofilm state lactic acid bacteria, and drying to obtain the high-activity lactic acid bacteria powder. According to the preparation method, the drying survival rate of the strain is remarkably improved, and the resistance of lactic acid bacteria to stress such as dehydration, heat stress and cold stress in the drying process is effectively enhanced.

The utility model relates to the technical field of culture medium shunting, in particular to an intestinal bacterium enrichment liquid culture medium self-flowing racking machine which is characterized in that when the racking machine is used, a plurality of groups of culture bottles are respectively placed on a bottle carrying assembly, and then the bottle carrying assembly is placed on a supporting table and is positioned and fixed through two groups of positioning assemblies; then liquid adding operation is conducted on the multiple sets of culture bottles through the flow dividing assembly, after liquid adding is completed, a worker integrally moves the multiple sets of culture bottles through the bottle carrying assembly, then the other set of bottle carrying assembly is placed and positioned, and the liquid adding efficiency is improved; comprising a supporting table, supporting legs and a liquid storage tank, the multiple sets of supporting legs are arranged at the bottom end of the supporting table, the liquid storage tank is installed at the top end of the supporting table, the distribution assembly is arranged at the output end of the liquid storage tank, the bottle carrying assembly is used for transferring multiple sets of culture bottles, and the two sets of positioning assemblies are symmetrically arranged at the top end of the supporting table.

The invention relates to the technical field of microbial fermentation equipment, in particular to a microbial agent fermentation culture device which comprises a fermentation tank, a mixing mechanism and a regulation and control mechanism are arranged in the fermentation tank, and a control system is arranged outside the fermentation tank; a motor is mounted at the top end of the fermentation tank, the mixing mechanism comprises a stirrer rotationally connected in the fermentation tank, an air inlet channel is formed in a shaft where the stirrer is located, a centrifugal impeller is mounted on the stirrer, and the centrifugal impeller is close to the cavity bottom of the fermentation tank; the regulation and control mechanism comprises a detection unit and a compensation assembly which are mounted on the fermentation tank, a gas supply device in the compensation assembly is automatically triggered, the supplementation amount of aerobic gas is increased, a control system automatically triggers a solvent tank in the compensation assembly, the supplementation amount of acid or alkali is automatically adjusted to the fermentation tank, and then the fermentation tank is started. The automatic balance adjustment of the acid-base culture conditions of the liquid culture medium is completed.

The invention discloses a method for inducing proliferation of paphiopedilum protocorm-like bodies by using oryzalin. Comprising the following steps: enabling paphiopedilum seeds to germinate in a germination culture medium to form buds; the buds are soaked and induced in the dark for 6-36 h, and an induction culture medium is a 1 / 2 MS liquid culture medium containing 0.5-5 mg / L of 2, 4-D, 0.05-1 mg / L of TDZ, 5-20 [mu] mol / L of oryzalin and 2% of dimethyl sulfoxide; inoculating the induced buds into a culture medium which does not contain oryzalin for culturing; carrying out proliferation culture on the protocorm-like body; carrying out differentiation culture on the protocorm-like body cluster; rooting and seedling strengthening culture; and transplanting rooted seedlings. According to the method disclosed by the invention, the sterile seeding buds of the paphiopedilum brevicornum protospecies are taken as the explants, the protocorm-like bodies are successfully induced, and the induction effect is remarkable. The research on differentiation, rooting, seedling strengthening and transplanting maintenance is systematically carried out, and a set of tissue culture and efficient rapid propagation technical system for paphiopedilum leucopeniculatum, which is low in cost, simple and convenient to operate and high in application value, is formed.

The invention provides a potassium-dissolving bacteria-iron-based potassium-containing nano material and a preparation method thereof, and belongs to a bio-fertilizer technology, and the preparation method comprises the following steps: dispersing soluble iron salt in water to obtain a solution A; dispersing a soluble phosphoric acid source and potassium salt in water to obtain a solution B; dispersing a stabilizer in water to obtain a solution C; simultaneously dropwise adding the solution A and the solution B into the solution C at the same speed, controlling the pH value to be 2.5-4.0 through alkali liquor, stirring for reaction, standing and aging to obtain the iron-based potassium-containing nano material; inoculating potassium-dissolving bacteria into a liquid culture medium, and carrying out enlarged culture to obtain a bacterial suspension; and mixing the bacterial suspension with the iron-based potassium-containing nano-material to obtain the potassium-dissolving bacteria-iron-based potassium-containing nano-material. The iron-based potassium-containing nano-material contains potassium, the iron-based potassium-containing nano-material and the potassium-dissolving bacteria act together to form a dual potassium supply mechanism that the potassium-dissolving bacteria decompose soil potassium and the iron-based potassium-containing nano-material releases potassium, and the effect is far better than that of single use of a microbial inoculum or a common potash fertilizer.

The invention relates to the technical field of bacterial cellulose preparation, in particular to a composite flora for producing bacterial cellulose and a preparation method thereof, and the preparation method comprises the following steps: screening gluconobacter oxydans, obtaining culture medium preparation materials and preparation tools, preparing a slant culture medium set, preparing an enriched liquid culture medium set, and preparing composite flora mixed inoculation liquid. The method comprises the following steps: preparing a waste tobacco leaf leaching solution, extracting a proportional leaching solution from the waste tobacco leaf leaching solution according to a preset proportion, obtaining a mixed fermentation culture medium based on a preparation tool and the proportional leaching solution, and carrying out inoculation operation on a composite flora mixed inoculation solution by using the mixed fermentation culture medium to obtain a dry cellulose membrane; calculating the yield of the bacterial cellulose based on the dry cellulose membrane, and completing the preparation of the composite flora for producing the bacterial cellulose based on the yield of the bacterial cellulose. The method can be used for scientifically, efficiently and stably preparing the composite flora.

The invention discloses 10-hydroxydecanoic acid as well as a preparation method and application thereof, and belongs to the technical field of cosmetics, Candida lipolytica is taken as a fermentation thallus, the Candida lipolytica contains alkane monooxygenase (CYP450), alcohol dehydrogenase (ADH), fatty alcohol oxidase (FAO) and fatty aldehyde dehydrogenase (FALDH), amplification and activation are performed on the Candida lipolytica in a seed culture medium, and the Candida lipolytica is obtained. The method comprises the following steps: inoculating a seed solution into a liquid culture medium, enabling a strain to adapt to a culture environment in advance, reducing strain death caused by environmental mutation after inoculation, inoculating the seed solution into the liquid culture medium, culturing until OD600 is 45-55, realizing high-density enrichment of the strain, being beneficial to increasing the content of CYP450, ADH, FAO and FALDH, adding decane and Tween 80, and enabling the Tween 80 to be capable of increasing the permeability of a cell membrane and increasing the reaction rate, the CYP450 is used for catalyzing decane to carry out hydroxylation, and ADH, FAO and FALDH are used for carrying out oxidation, so that the high-purity 10-hydroxydecanoic acid is obtained.