132 results about "Aflatoxin" patented technology

The invention discloses a method for detecting aspergillus flavus and aflatoxin B1 of crops based on an infrared spectrum. The method comprises the steps of crop sample material collection, rice multi-strain mould infection, spectrum collection, crop sample aflatoxin B1 determination, spectrum pretreatment, correction model construction and model verification. The invention aims at detecting the content of aspergillus flavus infection and toxin B1 thereof in crops by combining a near-infrared spectrometer and a stoichiometric method. The method has the advantages of being simple and easy to implement, high in analysis speed, high in detection precision, low in analysis cost, free of any pollution to the environment and the like, samples do not need any pretreatment, and the method has important practical value for guaranteeing the quality safety of agricultural products and reducing the carcinogenic risk of people.

The invention discloses a coarse cereal aflatoxin detection method combining hyperspectral imaging and deep learning, and belongs to the field of agricultural product quality safety detection. The method comprises the following steps: firstly, acquiring hyperspectral imaging data of coarse cereal grains, extracting space and spectral information, forming basic data, and performing preprocessing, space-time registration and feature alignment; building a hyperspectral space-spectrum double-branch feature fusion convolutional neural network deep learning model, and importing the processed data to complete iterative training; and finally, performing same-standard data acquisition and processing on to-be-detected coarse cereals, importing the trained model, and realizing aflatoxin detection and pollution area positioning through pixel-level analysis. According to the method, deep fusion of space and spectral features is realized, the detection accuracy and generalization ability are effectively improved, the detection result is stable, reliable and traceable, and the fine detection requirement of aflatoxin in coarse cereals is met.

The invention relates to the technical field of nondestructive testing, in particular to a corn feed aflatoxin content nondestructive testing method based on deep learning, which comprises the following steps: acquiring a hyperspectral image of a corn feed sample; correcting the hyperspectral image; taking the center of the corrected hyperspectral image as a base point, and extracting a plurality of regions of interest; determining whether the working state of the hyperspectral imaging system is stable based on the confidence coefficient fluctuation value, and adjusting the light source intensity of the hyperspectral image according to the ratio; determining the accuracy of the aflatoxin content predicted value based on the detection accuracy rate, and adjusting the weight attenuation coefficient of the deep learning model according to the difference value; and determining whether the stability of the aflatoxin content detection process is qualified or not based on the detection accuracy fluctuation value, and optimizing the deep learning model hyper-parameters according to the relative difference between the qualification rate fluctuation value and a preset qualification rate fluctuation value. The nondestructive detection accuracy of the aflatoxin content of the corn feed is improved.

The invention discloses a method for detecting aflatoxin B1 in coffee based on colorimetric and photo-thermal dual modes of MXene (at) Pt nano-enzyme, which comprises the following steps: etching Ti3AlC2 by using LiF and HCl to obtain MXene, synthesizing platinum nano-particle modified MXene nano-enzyme (MXene (at) Pt) by using dopamine carbon dots and sodium borohydride as reducing agents and adopting an in-situ reduction technology, and detecting aflatoxin B1 in coffee by using the MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt). The MXene (at) Pt shows near-infrared light stimulation enhanced peroxidase-like activity and photo-thermal performance and can catalyze blue deepening and temperature rising of a substrate 3, 3 ', 5, 5'-tetramethyl benzidine (TMB), when aflatoxin B1 exists, POD-like activity of MXene (at) Pt nano-enzyme is inhibited, and colorimetric and temperature signals are reduced; a method for detecting the AFB1 by the colorimetric temperature dual-mode sensor is established, and the method has the characteristics of high sensitivity, strong specificity, simplicity and rapidness in operation and the like.

The invention discloses an intelligent quintuplet cooperative plasma self-purification robot long-term storage system and a self-adaptive disinfection control method. According to the system, cold plasma, ozone, chlorine dioxide, self-generated nitric oxide and a charge self-purification jump effect are fused, and a dynamic self-purification system with an electric field-gas field-chemical field-intelligent field-thermal field five-dimensional synergistic energy field is constructed. The robot adopts a three-section structural layout and a multi-mode self-adaptive propulsion mechanism, environmental parameters are sensed through AI, discharge power and oxidant release are intelligently regulated and controlled, and precise sterilization, toxicity reduction and mildew prevention in a multi-medium environment are achieved. The system can generate various high-energy active species containing. OH, O, NO, ClO, ONOO and the like, chain splitting decomposition and oxidation mineralization are carried out on mold spores, bacterial cells, aflatoxin and the like, the sterilization rate reaches 99.995%, and the toxin degradation rate exceeds 98%. The system has the characteristics of no residue, low energy consumption, long-acting self-maintenance and the like, is suitable for multiple scenes of grain storage, traditional Chinese medicinal materials, cold chains, farmland, public health and the like, and realizes an intelligent, continuous and chemical-additive-free green storage and dynamic purification system.

This invention discloses a laccase mutant, Lcc5-I479T, its expression strain, and its applications. Using laccase from *Coprinopsis cinerea* as the starting enzyme, this invention obtained the mutant gene through molecular docking and positional analysis. After induction expression in engineered bacteria containing the mutant gene, the stable laccase mutant enzyme Lcc5-I479T was obtained. Using ABTS as a substrate, the mutant enzyme Lcc5-I479T showed a stable increase in activity to 8-20 times that of the starting enzyme at 35-50℃. This mutant enzyme has potential application value in the oxidative transformation of aflatoxin.

The invention discloses a nano-enzyme detection method for aflatoxin B1, and relates to the technical field of analysis and detection.The method comprises the following specific steps that nano-enzyme preparation and carrier selection are conducted, specifically, nano-gold is prepared through a sodium citrate reduction method to serve as the nano-enzyme, a chloroauric acid solution is added into a round-bottom flask and heated to be boiled, and a carrier is obtained; according to the method, the PNIPAM serves as an immobilization carrier of the nano-enzyme, reversible immobilization of the nano-enzyme is achieved, cyclic utilization of the nano-enzyme is promoted, the detection cost is reduced, after detection is completed, phase change of the PNIPAM can be achieved by changing environmental conditions, and therefore effective separation of nano-gold and the carrier is achieved; after the recovered nanogold is washed and subjected to re-functionalization treatment, the catalytic activity of the nanogold is maintained, and the nanogold can be used for detecting aflatoxin B1 again, so that the utilization rate of the nano-enzyme is increased, and the waste of resources is reduced.

The invention relates to the technical field of microbial degradation, and in particular relates to achromobacter margaritae AM6232 and an application thereof in biological detoxification of aflatoxin. The achromobacter mardeprae AM6232 is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the preservation number is CGMCC NO.34864. The achromobacter mardelpicae AM6232 and the culture thereof have a good degradation effect on various aflatoxins, especially have a high degradation rate on aflatoxin AFB1, and can be used for removing aflatoxins in agricultural products.

The invention discloses a method for detecting the content of aflatoxin in breeding feed, and relates to the technical field of feed safety detection.The method comprises the steps that near-infrared, fluorescence and Raman spectrums of a feed sample to be detected are synchronously collected, and an original spectrum data stream is formed; carrying out parallel preprocessing on the data stream, suppressing noise and correcting a baseline to obtain an optimized spectrum data set; extracting multi-modal spectral features from the data set, fusing the multi-modal spectral features, and constructing a multi-dimensional feature matrix representing the toxin content; inputting the matrix into a pre-trained grading detection model to obtain a preliminary prediction value of the toxin content and corresponding uncertainty evaluation; and in combination with calibration sample data in a historical detection database, performing dynamic calibration compensation on the preliminary predicted value, and outputting a final aflatoxin content report. Through multi-source spectral information fusion and dynamic self-calibration, the accuracy, stability and long-term reliability of aflatoxin detection in a complex feed matrix are improved.

The application belongs to the technical field of biology and particularly relates to a kind of biomimetic enzyme and its application in degrading aflatoxin.The raw material of the biomimetic enzyme includes polypeptide and divalent copper ion, the sequence of the polypeptide is shown in SEQ ID No.1, specifically: Ac-HCHLKLKLKL-CONH2, the N terminal of the polypeptide is acetylated, and the C terminal is amidated.The biomimetic enzyme is constructed by sequencing design and metal coordination to construct an active site, is stable in catalyzing AFB1 rupture in wide pH and temperature, has the advantages of good tolerance, high catalytic efficiency, and has potential application advantages in the application in grain and feed purification.

The application belongs to the technical field of material application, and particularly relates to a graphitized carbon material and a preparation method and application thereof, the preparation method of the graphitized carbon material is as follows: (1) D-(+)-xylose powder and transition metal salt powder are weighed and uniformly ground; (2) after sieving, calcination is carried out under an inert gas atmosphere; (3) after grinding and sieving of the calcined product, washing is carried out with 1.0 mol / L dilute hydrochloric acid solution, then washing is carried out with distilled water and drying is carried out, to obtain the graphitized carbon material, the graphitized carbon material has high adsorption efficiency on aflatoxin B1 (AFB1) in vegetable oil, and in combination with magnetic solid phase extraction (MSPE) and high performance liquid chromatography-fluorescence detection (HPLC-FLD) technology, the detection limit is as low as 2.0 pg·g ‑1 The graphitized carbon material has excellent regeneration performance, and the material consumption and cost in the detection process are significantly reduced.

The invention belongs to the technical field of food processing, and discloses a preparation method of fragrant nutritional peanut oil, which is based on a second-order squeezing process, and specifically realizes preparation of high-nutrient fragrant peanut oil through the working procedures of raw material soaking, irradiation germination, drying, crushing, pre-squeezing, puffing, solid state fermentation, steaming and frying, squeezing and the like. The obtained peanut oil has the characteristics of high extraction yield, rich nutrient substances, strong flavor, low content of harmful substances such as aflatoxin and benzopyrene, and the like.

The invention discloses bacillus subtilis, a complex microbial inoculant and application of the complex microbial inoculant to degradation of mycotoxin, and belongs to the field of microorganisms and fermentation engineering. According to the invention, a strain of bacillus subtilis BLYC-1937 with the activity of degrading mycotoxin is obtained through screening, and the bacillus subtilis BLYC-1937 has a good degradation effect on pollution of single toxin of T-2 toxin, vomitoxin, fumonisins B1, aflatoxin B1 and ochratoxin A or combined pollution of multiple toxins; the strain has good antagonism on fusarium oxysporum capable of producing T-2 toxin and aspergillus ochraceus capable of producing ochratoxin A, and pollution of T-2 toxin and ochratoxin A can be reduced from the source.

The invention discloses a near-zero background fluorescence sensor based on polydopamine functionalized MXene as well as a preparation method and application of the near-zero background fluorescence sensor, and belongs to the technical field of universal biosensing. The sensor comprises a polydopamine functionalized MXene material and a quantum dot-aptamer fluorescent probe which is accurately coupled by click chemistry in a ratio of 1: 1. The detection method is characterized in that a target object is utilized to induce the probe to desorb from the surface of a material, and a supernatant containing the free probe is physically separated from a material precipitate through centrifugal separation, so that background fluorescence interference is almost completely eliminated. According to the invention, ultra-sensitive detection of aflatoxin B1 is realized, and the detection limit of AFB1 in complex matrixes such as corn flour is as low as 0.27 mu g / kg. All components of the platform can be modularly and independently stored for a long time, the platform can be directly applied to detection of various micromolecular mycotoxins without optimization by replacing aptamers, and the platform has high sensitivity, high stability and high universality.

The invention belongs to the technical field of genetic engineering antibodies, and particularly relates to an antibody for non-competitive detection of aflatoxin B1 and application of the antibody. The antibody comprises a nano antibody of an anti-aflatoxin B1 antigen-antibody immune complex and a monoclonal antibody of the anti-aflatoxin B1; the amino acid sequence of the nano antibody of the anti-aflatoxin B1 antigen-antibody immune complex is as shown in SEQ ID NO. 1; the monoclonal antibody for resisting aflatoxin B1 comprises a heavy chain and a light chain; the amino acid of the heavy chain is as shown in SEQ ID NO.10, and the amino acid of the light chain is as shown in SEQ ID NO.11. The antibody for non-competitive detection of aflatoxin B1 provided by the invention is low in cost, can be prepared on a large scale through a prokaryotic expression system, is simple and convenient to prepare, has strong operability, and can be applied to non-competitive immunological analysis of aflatoxin B1.

This invention belongs to the field of biosensor technology, specifically relating to an aflatoxin B1 sensor based on exchange catalysis and photocurrent polarity reversal, its preparation method, and its application. The sensor includes a reference electrode, a photosensitive substrate electrode, an AFB1-specific aptamer-trigger chain conjugate, a basement exchange catalytic nucleic acid amplification system, and an h-Zn1Cd5S-hairpin H conjugate. The sensor constructed by this invention is easy to operate, has a fast response speed, good repeatability, high detection sensitivity, and specificity. It can avoid interference from signal fluctuations, and its preparation method is simple, showing broad application prospects in aflatoxin B1 detection.

The invention belongs to the technical field of feed biology, and particularly relates to an aflatoxin oxidase mutant as well as a coding gene and application thereof. According to the three-point combined mutant E188R-S210G-T418A provided by the invention, the enzyme activity is 177% of that of a female parent BlCotA; after water bath is carried out for 30 minutes at 80 DEG C, the enzyme activity is 68% of the initial enzyme activity, and the thermal stability is superior to that of a female parent BlCotA; after the mutant E188R-S210 G-T418A is used for treating raw milk for 1 hour, 2 hours and 4 hours, the residual quantity of the AFM1 is respectively reduced to 0.31 ng / mL, 0.12 ng / mL and 0.01 ng / mL; after corn steep liquor is treated by the mutant E188R-S210G-T418A, the degradation rates of AFB1, AFB2, AFG1 and AFG2 are respectively 93.71 percent, 93.95 percent, 96.79 percent and 97.58 percent.

This application discloses an aflatoxin B1 sensor and detection method based on a hydrogel whispering-gallery mode microcavity enhanced by liquid crystal droplets, comprising the following steps: A1: preparing a hydrogel-glass microbubble enhanced by liquid crystal droplets; A2: stretching a single-mode fiber by flame heating to obtain a tapered fiber, adjusting the relative position of the tapered fiber and the hydrogel-glass microbubble enhanced by liquid crystal droplets, and incident a laser emitted by a scanning laser, which enters the first single-mode fiber through the tapered fiber to achieve optical field coupling, resulting in an optically coupled hydrogel-glass microbubble enhanced by liquid crystal droplets. The laser then enters the second single-mode fiber through the tapered fiber. The aflatoxin B1 solution to be detected is added to the optically coupled hydrogel-glass microbubble enhanced by liquid crystal droplets, and the concentration of the aflatoxin B1 solution is calculated by recording the optical information. This application solves the problem of low sensitivity caused by visual observation or broadband monitoring commonly used in hydrogel sensors and liquid crystal sensors.

This invention discloses a method for detecting aflatoxin B1 based on a BIC terahertz metamaterial sensor. Based on electromagnetic theory and the time-domain finite-difference method, a continuous-domain bound-state (BIC) terahertz metamaterial sensor was designed. Using this BIC terahertz metamaterial sensor, terahertz enhanced spectra of aflatoxin B1 solutions of different concentrations were acquired. Analysis revealed that the amplitude of the transmission peak of aflatoxin B1 around 1.5 THz gradually decreased with increasing aflatoxin B1 solution concentration, while the frequency of the transmission peak gradually shifted to lower frequencies with increasing aflatoxin B1 solution concentration. PLS and LS-SVM quantitative models for aflatoxin were established. Analysis showed that the LS-SVM model performed better, and the detection limit for aflatoxin B1 was found to be 2.04 × 10⁻⁶. ‑7 μg / ml. This invention enables rapid, non-destructive, and highly sensitive detection of aflatoxin B1 in grains.

The invention belongs to the technical field of aflatoxin detection, and relates to an aflatoxin detection method based on a surface plasma resonance effect, a kit and application. Comprising the following steps: S1, preparing a lysine functionalized gold / silver nanoparticle solution; s2, adding an aflatoxin standard solution with known concentration into the Hg < 2 + > standard solution, oscillating and incubating, and then adding the lysine functionalized gold / silver nanoparticle solution to construct an aggregation colorimetric reaction system; and a series of aggregation colorimetric reaction systems. S3, acquiring color data by a machine image recognition technology, wherein the color data comprises an R value, a G value and a B value; s4, constructing a standard curve; s5, color data of a to-be-detected sample are obtained, and the content of aflatoxin in the to-be-detected sample is obtained through the standard curve. Visual quantitative analysis detection of aflatoxin is realized, the sensitivity is ensured, the detection process is simple, and the test efficiency is high.

The invention discloses sampling equipment for detecting aflatoxin in thick broad-bean sauce, and relates to the technical field of food detection equipment. The equipment comprises a rotary table arranged above a transmission mechanism, a sauce dipping rod mounting mechanism, a test paper belt conveying mechanism and a sauce dipping rod dismounting mechanism, wherein four sauce dipping rod fixing mechanisms are arranged on the rotary table in the circumferential direction. During working, the sauce dipping rod mounting mechanism automatically mounts a sauce dipping rod on the fixing mechanism at a mounting station; the rotating disc rotates to drive the sauce dipping rods to sequentially move to a dipping station to dip the thick broad-bean sauce in the packaging bottle, and then the sauce dipping rods move to a detection station to automatically smear the thick broad-bean sauce on the test paper tape; and finally, the sauce dipping bar dismounting mechanism automatically removes the used sauce dipping bars at the dismounting station. According to the invention, the full-process automation from sampling to smearing is realized, the manual operation is effectively replaced, and the device has the remarkable advantages of high working efficiency and good sampling consistency.

A method for detecting an aflatoxin on a seed which includes determining wavelengths at which there is greatest difference in reflectance intensities of control and contaminated seed, and comparing reflectance intensities from the captured image with reflectance intensities indicative of an aflatoxin presence at a predetermined concentration. Seeds are ejected that have an aflatoxin concentration greater than the predetermined concentration as indicated by the reflectance intensities from the captured images. Examples of seeds include a nut or legume.

The invention relates to the technical field of harmful substance detection, in particular to a three-channel colorimetric sensor for simultaneously detecting aflatoxin and a precursor thereof as well as a preparation method and application of the three-channel colorimetric sensor. According to the method, COFFe / NiP-Ph is utilized for catalyzing 3, 3 ', 5, 5'-tetramethylbenzidine (TMB) to be oxidized to generate blue oxTMB, o-phenylenediamine (OPD) is utilized for generating yellow oxOPD, and then the aflatoxin and the precursor thereof are detected through a three-channel colorimetric sensor. Purple ox4-AT is generated by using a mixture of N-ethyl-N-(3-sulfopropyl)-3-methylaniline sodium and 4-aminoantipyrine (4-AT), so that the colorimetric response is realized in a short time. The preparation method of the COFFe / NiP-Ph nano enzyme comprises the following steps: 1, a synthesis process of Fe-TAPP; 2, synthesis of Ni-TAPP is carried out; and 3, synthesizing the iron / nickel porphyrin covalent organic framework. The colorimetric sensor can be prepared into a detection reagent or a kit so as to realize qualitative and quantitative detection of aflatoxin and a precursor thereof in a sample to be detected. The detection method is simple and convenient to operate, and complex pretreatment on a to-be-detected sample is not needed; the detection cost is low, the detection is quick, and the requirement on a detection instrument is low.

The application discloses a chromogenic test paper for detecting aflatoxin and a preparation method thereof. The method adds montmorillonite to Fe(OH)3 colloid and mixes, and drops the mixture on a nitrocellulose membrane and waits for it to dry. The mixed solution of the Fe(OH)3 colloid and the montmorillonite in the application has an adsorption effect on the aflatoxin, forms a color block under the particle agglomeration effect, and realizes visual detection of the aflatoxin.

The invention discloses a plant lactobacillus and application thereof in relieving aflatoxin B1 induced liver injury, and relates to the technical field of microorganisms. The lactobacillus plantarum disclosed by the invention is lactobacillus plantarum TY-1, and the preservation number of the lactobacillus plantarum TY-1 in the China Center for Type Culture Collection (CCTCC) is CCTCC NO: M 20251682. The lactobacillus plantarum TY-1 disclosed by the invention has the advantages that the lactobacillus plantarum TY-1 is a lactobacillus plantarum TY-1, and the preservation number of the lactobacillus plantarum TY-1 in the China Center for Type Culture Collection (CCTCC); the bacterial strain has bacteriostatic activity and better oxidation resistance, and can effectively reduce the level of proinflammatory factors in serum, down-regulate the relative expression of pro-apoptosis genes and reduce the apoptosis of liver cells, thereby effectively relieving the damage to the liver caused by exposure to aflatoxin B1.

The invention discloses a method for detecting aflatoxin in silkworm chrysalis meal. According to the invention, a salting-out auxiliary liquid-liquid extraction technology and a supramolecular solvent extraction technology are integrated and are executed by an automatic salting-out extraction device specially designed for a pretreatment process, so that a system and a scheme for detecting aflatoxin in silkworm chrysalis meal, which integrate a special device, a core reagent and a detection method, are provided; a detection method which is green, environment-friendly, rapid, efficient, low in cost, high in sensitivity and good in accuracy is established. The preparation method comprises the following specific steps: preparing a supermolecular solvent consisting of n-heptanol, tetrahydrofuran and water and a saturated aqueous solution; the method comprises the following steps: mixing a silkworm chrysalis meal sample with a supramolecular solvent and ammonium sulfate, and carrying out vortex, centrifugation, constant volume and filtration to obtain a test solution; and carrying out quantitative analysis by adopting a matrix matching standard curve. The method is simple and convenient to operate, low in organic solvent consumption and low in cost, and is suitable for high-throughput rapid screening and quantitative detection of trace aflatoxin in silkworm chrysalis meal.

The application provides an anti-aflatoxin B1 monoclonal antibody and application, and particularly relates to an anti-aflatoxin B1 monoclonal antibody containing only a heavy chain variable region, a nucleotide coding the antibody, an expression vector carrying the monoclonal antibody or a nucleotide sequence coding the monoclonal antibody. The application screens and prepares an antibody for aflatoxin B1 from a phage nanobody synthesis library and applies the antibody to detection or identification of aflatoxin B1. The affinity constant of the antibody is 1.96E-07, the antibody can effectively detect aflatoxin B1, and can be identified from other common fungal toxins.

This invention discloses a strain of *Burkholderia lagoon* and its application in antagonizing *Aspergillus flavus*, belonging to the field of microbial technology. The *Burkholderia lagoon* strain is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 38387. This strain can both inhibit the growth of *Aspergillus flavus* and efficiently degrade aflatoxin B1, thus showing good application prospects and value in the field of food production safety technology.

The application discloses a centrifugal extraction and recycling device for aflatoxin detoxification of edible oil in the technical field of edible oil detoxification equipment, which comprises a centrifugal tank and a distillation device, a plurality of groups of lower connecting ends are arranged on the centrifugal tank, the lower connecting ends are divided into left connecting ends and right connecting ends, positioning assemblies are arranged in the left connecting ends and the right connecting ends, the positioning assembly comprises: a mounting cavity which is arranged on the inner side of the left connecting end and the right connecting end; an inner sleeve connecting end, both ends of the inner sleeve connecting end can be connected with an external hose; a control assembly, the control assembly comprises a positioning system and an adjusting system, the positioning system can fasten the external hose on the surface of the inner sleeve connecting end, and the adjusting system can slightly adjust the flow cross section inside the inner rubber ring, the hose is clamped and fixed through the left connecting end and the right connecting end, the air pressure is used as the fastening hose and the adjusting liquid flow, so that the flow is more accurately adjusted, and the accuracy of the adjusting valve body is not affected by vibration.