744 results about "Aflatoxin" patented technology

The invention relates to an aflatoxin nano antibody gene pool, a construction method and application of the aflatoxin nano antibody gene pool as well as an aflatoxin B1 nano antibody 2014AFB-G15. The aflatoxin nano antibody gene pool is prepared by extracting RNA (ribonucleic acid) in alpaca blood after immunization of an aflatoxin B1 antigen, performing specific amplification on a variable region gene of an alpaca heavy chain antibody by adopting an RT-PCR (reverse transcription-polymerase chain reaction) method to obtain an aflatoxin nano antibody VHH gene, and then performing transformation after connecting with a pCANTAB5E (his) vector. The aflatoxin B1 nano antibody 2014AFB-G15 obtained by screening, disclosed by the invention, has the characteristics of organic reagent resistance, high temperature resistance and the like, and is good in stability; the IC50 (half maximal inhibitory concentration) of the aflatoxin B1 nano antibody 2014AFB-G15 to the aflatoxin B1 is 0.66ng / mL, and the cross reactivity of the aflatoxin B1 nano antibody 2014AFB-G15 to the aflatoxins B2, G1,G2 and M1 is 22.6%, 0.95%, 32.1% and 26% respectively.

The invention provides a hybridoma cell line 1C11 and an anti-aflatoxin general monoclonal antibody secreted by the same as well as the applications thereof. The hybridoma cell line 1C11 can be used for preparing a high-titer aflatoxin antibody, and a mouse hydroperitoneum antibody is measured to reach 5.12*106 by using an ELISA (Enzyme-Linked Immunosorbent Assay). The anti-aflatoxin general monoclonal antibody has high sensitivity, respectively reaches the IC50 (50% inhibiting concentration) of aflatoxin B1, B2, G1 and G2 to be 1.2, 1.3, 2.2 and 18.0 pg / mL, is the antibody with highest sensitivity among currently reported four aflatoxin antibodies, is used for measuring the total aflatoxin amounts, i.e. the total amounts of the aflatoxin B1, B2, G1 and G2 and has great practical application values.

The invention discloses a refining process for cold-pressed camellia oil at low temperature. The process disclosed by the invention comprises the following steps: processing raw materials; cold-pressing to obtain oil; carrying out high-precision filtration; hydrating and degumming; deacidifying; decolorizing; deodorizing; and dewaxing. According to the process disclosed by the invention, the harmful ingredients (for example, benzopyrene, free fatty acid, colloid, trace heavy metals, residual soap, debris, aflatoxin and the like) existing in the camellia oil and generated in the production process, and a unique unfavorable smell of the camellia oil are effectively removed; various unique natural beneficial nutrients of the camellia oil can be preserved to the maximal extent after the camellia oil is refined; and no harmful substance is generated in the processing process.

The invention discloses a method for detecting aflatoxin through an immunosensor. The aflatoxin (AFT) is a fungal toxin which has the high carcinogenicity, teratogenicity and toxicity, and accurate and rapid analysis on the aflatoxin is one of most effective means for reducing and avoiding harm of the aflatoxin. A prepared gold-polyaniline-graphene (Au-PANI-GN) composite nanomaterial is represented by adopting an ultraviolet spectrum and a transmission electron microscope and used for constructing the electrochemical immunosensor, the electrochemical immunosensor is represented by adopting a cyclic voltammetry method, an electrochemical AC impedance method and a square wave voltammetry method, and the prepared electrochemical immunosensor detects the aflatorxin B1. Experiment results show that the constructed electrochemical immunosensor has the good electrochemical activity on detection of the aflatoxin, and the concentrations of the aflatoxin and peak currents have the good linear relation, wherein the linear equation of the relation is y=-0.177x+4.28.

A fresh vegetable foodstuff such as fruit, vegetables, grains or nuts is treated to reduce microbial contamination (UV-C irradiation, preferably in a CO2 atmosphere, preferably at −1 to +4° C.) and / or to induce protective phytoalexins (UV-A, UV-B and UV-C irradiation) and / or to destroy aflatoxins (UV irradiation, primarily UV-C). A modular system can be readily adapted to different foodstuffs. It can include treatment modules and support modules (e.g. for cleaning elements of the treatment modules, providing them with controlled environments, and controlling the input of foodstuffs so they are susceptible to treatment).

The invention relates to an aflatoxin B1 flow lag immunization time distinguishing fluorescence rapid-detection kit and an application thereof. The kit comprises a fluorescent test strip and a sample reaction bottle containing an europium-labeled anti-aflatoxin B1 monoclonal antibody lyophilized product, wherein the fluorescent test strip comprises a cardboard, a water absorption pad, a detection pad and a sample pad are sequentially pasted on one surface of the cardboard from top to bottom, adjacent pads are connected at the connection in an overlapping manner, the detection pad treats a cellulose nitrate membrane as a base pad, a transverse quality control line and a detection line are arranged on the cellulose nitrate membrane from top to bottom, the quality control line is coated with a rabbit anti-mouse polyclonal antibody, and the detection line is coated with an aflatoxin B1 bovine serum albumin conjugate; and the anti-aflatoxin B1 monoclonal antibody is secreted by a hybridoma cell strain having a preservation number of CCTCC NO.C201015. The kit can be used for the quantitative determination of the content of the aflatoxin B1, and has the advantages of simple operation, rapidness and high accuracy.

The invention relates to a Bacillus subtilis ANSB 060CGMCC No.3440 used for degrading aflatoxins, and culture method and application thereof. The invention also provides a method for degrading aflatoxins B1, G1 and M1 by fermentation liquor of the strain. By the method, the Bacillus subtilis is reacted with the aflatoxin B1 for 2 hours, has a degradation rate of over 70 percent on the aflatoxin B1, and has the degradation rate of over 80 percent after the reaction performed for 12 hours; and the Bacillus subtilis has the degradation rates of over 80 percent and over 60 percent on the aflatoxin G1 and aflatoxin M1 respectively. The Bacillus subtilis has high detoxification activity, strong specificity, mild action effect, and no damage to nutrient in feeds, and is suitable for removing the aflatoxins in the feeds.

The invention relates to a method for reducing the heavy metal content of rice and products thereof. The method comprises the steps of soaking in alkaline liquid, separation, reaction, washing, drying and the like; the process realizes different degrees of removal effects on aflatoxin and heavy metals such as cadmium, arsenic, lead and mercury, and can effectively reduce the heavy metal content of rice and rice products such as rice noodles, starch, rice protein powder and the like prepared from rice; the method provided by the invention is simple in product, low in production cost and easy to implement; the heavy metal index of the produced product conforms to the requirements of national standard.

The invention discloses a novel method for rapid detection of aflatoxin in food. The novel method studies extraction, purification and enrichment of aspertoxin in food and detects aflatoxin in food by using a combination of high performance liquid chromatography, on-line post-column photochemical derivatization and a fluorescence detector. The method employs a combination of dispersive magnetic solid-phase micro-extraction and dispersive liquid-liquid micro-extraction techniques for extraction, purification and enrichment of aspertoxin in a sample. Compared with a conventional determination method for aflatoxin, the method provided by the invention has the characteristics of a small amount of an organic solvent used in detection, short analysis time, simple operation, low detection cost, accuracy, etc.

The invention provides an online aflatoxin detecting device. The online aflatoxin detecting device comprises multiple light source transmitting and signal receiving integration units distributed at the two sides of a material track, and an upper computer. Each illuminating system comprises an ultraviolet source and a rotating reflection mirror which reflects the ultraviolet source to generate a line light source in the material perpendicular direction. Each signal receiving integration unit receives signals of multiple fluorescence wavelengths of bounce light at the same position of the surface of the same material, and converts the signals into electrical signals. The upper computer selects the signals of any three paths to be synthesized into a color image. A sensor in each optical signal receiving device is a single-point photoelectric detector. The invention further discloses material sorting equipment adopting the detecting device. The detecting device has the advantages that the weak fluorescence signals on the surfaces of the materials are effectively detected, each detected material point is only detected by the corresponding single-point photoelectric detector once, signal superposition is avoided, influence of material rolling, jumping and the like is eliminated, and the materials contaminated by aflatoxin and the normal materials are effectively distinguished.

The invention discloses a test strip for detecting aflatoxin B1 or M1 by utilizing an aptamer. The test strip for detecting the aflatoxin B1 or M1 by utilizing the aptamer, provided by the invention, comprises a sample absorption pad, a marker pad, a reaction film and a water absorption pad, wherein the marker pad is coated with a detection probe; the detection probe is an aflatoxin B1 aptamer marked by fluorescein; the nucleotide sequence of the aflatoxin B1 aptamer is sequence 1; the reaction film comprises a detection region and a quality control region; the detection region is coated with a conjugate formed by an aflatoxin B1 hapten and a carrier protein; and the quality control region is coated with a quality control probe, and the quality control probe is a conjugate formed by avidin conjugation probe marked aflatoxin B1 complementary single strand DNA (Deoxyribose Nucleic Acid)) molecules. The test strip for detecting the aflatoxin B1 or M1, provided by the invention, has the advantages of high sensitivity, accuracy in quantifying, strong specificity, simplicity and convenience, and short detection time.

The invention discloses a method for rapidly detecting the content of aflatoxin. The method comprises the following steps of: after smashing a sample to be detected, putting the sample powder into a beaker, and adding an extractant for shaking or performing ultrasonic extraction; filtering, performing water bath evaporation on a filtrate, and metering the volume to obtain a test sample; respectively pointwise adding the test sample and an aflatoxin B1 standard substance which are commensurate on a thin-layer silica gel plate, pointwise adding derivative reagents into sampling points, and respectively developing by developers; and comparing the fluorescence intensity of the test sample and the aflatoxin B1 standard substance under an ultraviolet lamp to judge whether the content of the aflatoxin in the test sample exceeds the standard. The method for rapidly detecting the content of the aflatoxin has the advantages of small solvent amount, simple sample treatment and short measurement time; the method does not need a professional, only needs small apparatus, and is particularly suitable for rapid field detection; and the method effectively avoids the harm and the pollution of trifluoroacetic acid to operators and the environment, improves the method sensitivity, and has the lowest detectable amount of 0.00032 mu g and the lowest detection limit of 3 mu g / kg.

The invention discloses an aptamer of aflatoxin B1 and a complementary DNA sequence of the aptamer, further discloses a method for quantitatively detecting aflatoxin B1, and belongs to the field of quantitative detection of aflatoxin B1. The method includes the following steps that 1, an aptamer biosensor is prepared; 2, aflatoxin B1 in a sample to be detected is extracted to obtain sample extraction liquor, the sample extraction liquor is added into the aptamer biosensor and evenly mixed, and incubation is performed; 3, supernatant liquor is separated, and an excessive sucrose solution is added for a reaction; 4, quantitative detection is performed through a glucometer. The method for quantitatively detecting aflatoxin B1 in food by combining the aptamer biosensor with the glucometer is easy and convenient to implement, good in specificity and repeatability and high in sensitivity and provides a new means for quantitatively detecting aflatoxin B1.

The invention discloses alum-free vermicelli which is prepared from the following raw materials in parts by weight: 0.3-0.5 part of compound gluten fortifier, 0.3-0.5 part of compound phosphate, 2.5-5.0 parts of denaturized starch, 100 parts of starch and a proper amount of water through the steps of mixing, stewing, freezing and airing. The invention also discloses a preparation method of the alum-free vermicelli which is prepared from the raw materials in the weight ratio through the following steps of pulping, filtering, purifying, dewatering, pouring starchy sauce over the dish, curing, vacuumizing, forming, ageing, airing and the like. The vermicelli provided by the invention contains no sulfur dioxide, lead or total arsenic, the aflatoxin content accords with the national standard, the lead content is far lower than the national standard requirement not higher than 100mg / kg; fine sand and dust mixed in the starch can be sufficiently removed through the filtering and purifying processes, and the vermicelli is pure in color and luster and contains the dust content which is not higher than 0.7%; and due to the adoption of the periodical ageing process, the inside and the outside of the vermicelli are frozen uniformly, no barring and white tip phenomena are caused, the broken bar rate is not higher than 3% after rehydration, vermicelli is straight in bar shape, smooth in taste and free of foreign smell.

The invention relates to an enzyme electrode for detecting sterigmatocystin and a preparation method thereof, and a biosensor which uses the enzyme electrode as a substrate electrode for fixing and assembling aflatoxin oxidase and is used for detecting sterigmatocystin. An L-cysteine functional film is self-assembled on the surface of a gold electrode, and then the gold electrode is immersed into heterozygous Prussian-blue electrode-position working solution to prepare the Prussian-blue heterozygous electrode by a potentiostatic method. CNT (carbon nano tubes) used as electron carriers are evenly dispersed in chitosan solution and are used as carriers for embedding aflatoxin oxidase. Then the chitosan- aflatoxin oxidase-CNT mixed film is assembled on the surface of the Prussian-blue heterozygous modified electrode, and finally, the biosensor used for detecting sterigmatocystin is obtained. The enzyme electrode and the biosensor provided by the invention have better stability and repeatability, quick response to sterigmatocystin, low voltage detection, strong antijamming capacity and excellent selectivity.

The invention discloses a method, a device and a system for removing aflatoxin, which is used for improving energy utilization ratio of ultraviolet rays to remove AFT, reducing the influence on edible oil flavor and quality in removing process. The technical scheme of the invention is as follows: the ultraviolet light source of a single wavelength is utilized in the method, grease is irradiated by an ultraviolet ray irradiation method to decompose the aflatoxin in the grease; and the wavelength range of the ultraviolet light source of the single wavelength is 355nm-375nm. The invention is applied to food oil processing.

A nondestructive system and method for aflatoxin detection based on red-orange fluorescence is described. A sorting plane is illuminated with a wide band black light source. At least one image of unsorted produce on said sorting plane is obtained. A red component of the at least one image is evaluated. Contaminated produce is determined based on the red component.

The invention discloses a non-transgenic soybean oil cold pressing preparation process which is characterized by including the steps of raw material selection and polishing and dehulling, pressing moisture adjustment, pressing and residual oil control, crude oil filtering, removal of lipoxygenase by hyperfiltration and removal of beany flavor by bumping in vacuum at the low temperature. Non-transgenic soybeans serving as raw materials eliminates potential hazard possibly caused by transgenic raw materials, and using the physical cold pressing technology enables a product to be free from organic solvent residues, eliminates contamination of aflatoxin on the raw materials and biological factors resulting in deterioration during soybean oil storage, effectively removes the beany flavor and other peculiar smell in soybean oil and is rich in natural antioxidants such as VE (vitamin E) and the like so that extra antioxidants do not need to be added during oil storage.

The invention belongs to the technical field of biology, and relates to an immunoaffinity adsorption material based on a single-domain heavy-chain antibody, in particular to an immunoaffinity adsorption material for aflatoxin. The material comprises a carrier and a ligand carried by the carrier, and is characterized in that the single-domain heavy-chain antibody specially recognizing aflatoxin is used as the ligand and has the amino acid sequence shown in SEQ ID NO.:1and the like. The antibody has the advantages of being resistant to acid, alkali and high temperature, easy to produce and the like, and important practical value is achieved for a low-cost immunological detection method which is used for aflatoxin and can be repeatedly used.

The invention discloses an Aspergillus flavus strain and mixed flora not producing aflatoxin and application thereof. The strain is Aspergillus flavus AF052 with a preservation number of CGMCC NO.9858 and a preservation data of November 20th, 2014, and Aspergillus flavus AF053 with a preservation number of CGMCC NO.9859, and a preservation date of November 20th, 2014. All the strain and flora can effectively inhibit the formation of aflatoxin in corn and peanut, and improve the quality of agricultural products. In addition, A051, AF052 and AF053 can also secrete cellulose. When the corn and straw treated by biocontrol flora prepared from the Aspergillus flavus are used as animal feed, the carried biocontrol bacteria can produce cellulose to degrade cellulose and improve the utilization efficiency of animal husbandry on feed.

The invention belongs to the technical field of food detection, and particularly relates to a fast instrumental analysis method for aflatoxins in foods. The invention discloses a fast instrumental analysis method for aflatoxins B1, B2, G1 and G2 in foods. The method comprises the following steps of: weighing a certain amount of sample; adding an acetonitrile-water solution in a certain ratio; performing ultrasonic extraction; and selecting specific parent ions and daughter ions by using a super-efficient liquid phase chromatography-mass spectrometer under a gradient elution condition to measure the content of the four types of aflatoxins. The method is simple and is high in efficiency and the precision of measurement results is high. By the method, four monomers of the aflatoxins are completely separated, and the recovery rate is high; and compared with the prior art, the method has the advantages of high speed and accuracy of detection and simple pretreatment, and can be used for accurately determining the nature and the quantity to meet requirements on research and detection.

The invention provides a method for detecting SERS of aflatoxin B1 molecules based on molecularly imprinted polymer coated gold core-shell nanoparticles, and relates to surface reinforced raman detection. According to the method, core-shell nano-particles taking gold nanoparticles as a core and molecularly imprinted polymer as a shell are synthesized by coating aflatoxin B1 molecularly imprinted polymer around the gold nanoparticles; the hole in the molecularly imprinted polymer can be used for specifically capturing the aflatoxin B1 molecules after template molecules in the molecularly imprinted polymer of the shell layer are eluted, and surface reinforced raman detection of aflatoxin B1 molecules can be realized since the aflatoxin B1 molecules are in an effective range of a gold nanoparticle plasma resonant magnetic field; and the molecularly imprinted polymer is obtained by eluting the molecularly imprinted shell layer prepared by using the aflatoxin B1 molecules as template molecules, and has highly specific adsorption for aflatoxin B1, and can be used as a SERS substrate for quantitative detection of aflatoxin B1. The method has the characteristics of high specificity and short sample analyzing time.

The present invention discloses a label-free visualization detection method and a label-free visualization detection kit of aflatoxin B1. According to the present invention, the nucleic acid aptamer of aflatoxin B1 is adopted as the molecule recognition element, colloidal gold is adopted as the signal report molecule, the nucleic acid aptamer is added to the gold colloid solution, and the aflatoxin B1 interacts with the nucleic acid aptamer in the presence of the aflatoxin B1 so as to lose the protection effect of the nucleic acid aptamer on the aflatoxin B1; after NaCl is added, the red color of the detection system is changed into the blue and purple color; and if no aflatoxin B1 exists in the system, the red color of the solution is remained. According to the method of the present invention, the detection result is directly visible without any detection equipment, the operation is simple without antibodies, any label modification and any washing separation processes, and the method is suitable for on-site rapid detection, further has characteristics of low cost, economy, low price, fast response, and is suitable for wide promotion.

The invention belongs to the technical field of activated carbon, and particularly relates to a peanut shell activated carbon for removing toxins in peanut oil and a preparation method thereof. The peanut shell activated carbon is prepared by carrying out pretreatment, extrusion molding, carbonization and activation on peanut shells. The preparation method comprises the following steps: pretreatment: carrying out hydrothermal treatment on the peanut shells, and pulverizing; extrusion molding: carrying out pressure molding with a granulator to obtain cylindrical granules of which the diameters are 4-8 mm and the lengths are 10-20 mm; heating, cooling in the absence of oxygen, crushing and screening to control the granule diameters at 1-3 mm; and introducing isothermal superheated vapor, storing in a sealed environment, and cooling to obtain the finished product. The activated carbon is prepared from the peanut shells which are accessible raw materials, thereby implementing utilization of waste peanut shells; and the obtained peanut shell activated carbon has the advantages of large specific area and small pore size, can simultaneously adsorb benzopyrene, aflatoxin and other harmful substances, and can prevent the peanut oil from oxidative rancidity.

The invention relates to a natural cleaning agent for removing residual pesticides on fruit and vegetable surfaces and a preparation method; the preparation method of the cleaning agent comprises the following steps: cleaning shells, removing heavy metal, sterilizing the shells, performing high temperature electrolysis and ionization of the sterilized shells to form solid powder, and refining with a mesh sieve to prepare nanometer powder; the cleaning agent comprises one or more than one natural shells according to certain weight ratios. The cleaning agent of the invention not only can remove residual toxic materials on fruit and vegetable surfaces, such as pesticides, sulfur dioxide and aflatoxin, prevent toxic materials from entering human body by eating of the fruit and vegetable, thus prevent continuous accumulation of the toxic materials in the body to damage human body health, but also has no toxicity or irritation to human skin, causes no secondary pollution of ecological environment, meets the development trend of green cleaning agents, and has good application prospects.

The invention relates to a preparation method of a magnetic mesoporous silicon dioxide adsorbent for removing aflatoxin in edible oil. The preparation method specifically comprises the following steps: (1) dissolving rice hull ash and an alkali solid to obtain a rice hull ash alkaline solution; (2) after adding ferric salt, quickly adding stronger ammonia water and heating and stirring; filtering and separating, washing, drying and grinding precipitate; (3) putting magnetic microparticles and a cationic surface active agent in a beaker, dropwise adding an adjuvant, carrying out ultrasonic dispersion, stirring, adding the rice hull ash alkaline solution to adjust the pH value, maintaining the temperature, and further stirring; and (4) after reaction, aging, carrying out centrifugal separation on the precipitate, washing the precipitate by deionized water for several times, and after drying, carbonizing and calcining the precipitate, removing the cationic surface active agent to obtain a product which is the magnetic mesoporous silicon dioxide adsorbent. The preparation method provided by the invention is simple in preparation process and mild in condition, raw materials are low in cost, and the obtained magnetic mesoporous silicon dioxide adsorbent is high in specific surface area, can be used for effectively removing aflatoxin B1 in edible oil, is easily separated from food materials, and can be repeatedly used.

The invention discloses a production method of edible rice bran oil. The production method comprises the following steps of: firstly, heating four-stage standard rice bran oil by a preheater and charging into a separator, evenly distributing the materials under high vacuum degree, due to the boiling point difference of various substances, separating light components of raw material oil in an evaporating way by a pressure reducing technology, heating heavy components, charging into a purifier, quickly evaporating, separating aflatoxin and pesticide residue in an evaporating way, filtering the treated rice bran oil, contacting with protective gas in a stripping tower, and discharging in a separating way, wherein the acid value of the rice bran oil discharged out of the tower bottom achieves the standard of first-stage rice bran oil; and dewaxing in a winterization way to obtain the first-stage rice bran oil. According to the production method, the first-stage rice bran oil product with high oryzanol content can be produced. The whole technical process separates by a pure physical method, so that nutrition components can not be damaged; the production method does not need adding of any annexing agents, so that the safety of the product can be guaranteed; and the production method does not generate any waste gas, sewage or solid waste.

The invention relates to a dual-label rapid response nucleic acid adapter probe, which consists of a nucleic acid adaptor, the 5' end and 3' end of which are labeled by a fluorescent chromogenic grouprespectively, and a complementary probe, the 5' end and 3' end of which are labeled by a fluorescent quenching group respectively. The nucleic acid adaptor is a nucleic acid adaptor which can especially identify aflatoxin B1, namely, AFB1 nucleic acid adaptor. The nucleotide sequence of the AFB1 nucleic acid adaptor is shown as SEQ ID NO: 1 in the sequence list. The complementary probe is complementary to two ends of the AFB1 nucleic acid adaptor. The nucleotide sequence of the complementary probe is shown as SEQ ID NO: 2 in the sequence list. The method can be used for rapidly detecting aflatoxin B1. The identification process, after the aflatoxin B1 is added, can be completed in one minute, and one aflatoxin B1 molecule can trigger the recovery of two fluorescent group signals with highsensitivity. The whole reaction is carried out in a homogeneous and constant temperature solution environment, and the operation is simple.