291 results about "Aflatoxin" patented technology

The invention relates to streptomyces cell and application thereof in efficient degradation of aflatoxin B1, the streptomyces cell is streptomyces cell AFB1-D02, and has been preserved in China General Microbiological Culture Collection Center (CGMCC), the preservation number is CGMCC No.33986, and the preservation date is March 26, 2025. The invention further discloses a preparation method of the streptomyces cell. The streptomycete S. cellostatus AFB1-D02 has the capability of efficiently degrading AFB1, and the degradation efficiency of the streptomycete S. cellostatus AFB1-D02 is obviously higher than that of other streptomycetes in the prior art.

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 provides bacillus velezensis H5 capable of producing broad-spectrum antibacterial substances and application of the bacillus velezensis H5. The preservation number of the bacillus velezensis H5 in the China General Microbiological Culture Collection Center is CGMCC No.32671. The bacillus velezensis H5 is separated from sea mud in a specific sea area, can generate antibacterial substances with broad-spectrum antibacterial activity, and mainly comprises bacitracin, surfactin and mycostatin. The antibacterial substance of the bacillus velezensis H5 is applied to preservation of perishable fruits such as grapes and the like and mildew prevention of cereals such as corn and the like, and can effectively inhibit spoilage of the perishable fruits and synthesis of mycotoxins such as aflatoxin and the like, and the action effect of the antibacterial substance is obviously superior to that of a food preservative natamycin. The invention provides a novel, green, safe and broad-spectrum antibacterial substance for preservation and fresh-keeping of fruits and mildew prevention of grains, and has important application value.

This invention relates to the field of biocatalysis technology, and more particularly to an aflatoxin oxidase, its preparation method, and its applications. This invention utilizes a self-designed artificial intelligence enzyme design workflow to de novo design a novel aflatoxin oxidase, DnD-AFO. Compared to the traditional wild-type AFO, DnD-AFO exhibits enhanced activity, better thermal stability (its activity is significantly superior to the wild-type after high-temperature granulation), and improved resistance to pepsin and acid. Furthermore, it further enhances the detoxification efficiency against aflatoxin, making it well-suited as a food or feed additive for applications in agriculture and food engineering, among other related industries, demonstrating significant commercial and added value.

The application discloses a kind of fungal laccase mutant Lcc5-G and its expression strain and application.The application is based on the fungal laccase from Coprinopsis cinerea heterologous expression since, by site-directed mutagenesis, obtain mutant gene.After fungal induction expression containing mutant plasmid, obtain laccase mutant enzyme Lcc5-G with improved specific activity, stability and AFB1 removal efficiency.When ABTS is used as substrate, the specific activity of the mutant is improved by 3 times, and the stability of the mutant enzyme is improved to 5 times of the original enzyme at 45 DEG C and pH 7.The mutant has potential application value in oxidizing aflatoxin.

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.

The present invention belongs to the field of biodegradation of mycotoxins, and specifically relates to a complex enzyme preparation for degrading aflatoxins, a complex enzyme preparation solution, and its preparation method and application. The complex enzyme preparation comprises: 35-45 wt% tyrosinase, 20-30 wt% cellulase, 8-12 wt% pectinase, 8-12 wt% xylanase, and 10-20 wt% mushroom laccase. Compared with existing chemical and biological detoxification technologies, the complex enzyme preparation of the present invention contains safe and non-toxic components, is simple to use, and has low economic costs. After treatment with the enzyme preparation solution, the cellulose and hemicellulose in the peanut meal are initially decomposed, making it easier for animals to digest and absorb, and having higher nutritional value and better economic benefits.

The invention discloses an aflatoxin B1 detection method based on a BIC terahertz metamaterial sensor, and designs a continuous domain bound state (BIC) terahertz metamaterial sensor based on an electromagnetic theory and a time domain finite difference method. Terahertz enhanced spectrums of aflatoxin B1 solutions with different concentrations are collected, and analysis finds that the amplitude of a transmission peak of aflatoxin B1 at about 1.5 THz is gradually reduced along with the increase of the concentration of the aflatoxin B1 solution, and the frequency of the transmission peak gradually moves to a low frequency along with the increase of the concentration of the aflatoxin B1 solution; a PLS and LS-SVM quantitative model of aflatoxin is established, analysis finds that the LS-SVM model has a better effect, and the detection limit of aflatoxin B1 is 2.04 * 10 <-7 > mu g / ml. By adopting the method disclosed by the invention, rapid, nondestructive and high-sensitivity detection of the aflatoxin B1 in the grains can be realized.

The utility model provides a dairy product detection workstation. The dairy product detection workstation comprises oscillation equipment, centrifugal equipment, reagent caching equipment, constant temperature equipment, a microplate reader and transfer equipment, the oscillation equipment is used for performing oscillation treatment on the container filled with the dairy products; the centrifugal equipment is used for performing centrifugal treatment on the centrifugal tube; the reagent caching equipment is used for storing a standard sample and a test reagent for testing, and the transfer equipment is used for mixing the test reagent with the standard sample and a dairy product sample respectively to obtain a first mixed solution and a second mixed solution; the constant-temperature equipment is used for heating and incubating the first mixed solution and the second mixed solution contained in the microwell plate; the microplate reader is used for detecting the incubated first mixed solution and second mixed solution to obtain the content of aflatoxin in the dairy product. And the transferring equipment can realize the transfer of the vessel and the solution among the equipment in the detection process. The dairy product detection workstation disclosed by the utility model can realize automation of aflatoxin detection, is high in detection efficiency and saves manpower.

The invention discloses a pure grain solid-state white spirit strict selection method based on Longshi multi-dimensional evaluation, and relates to the technical field of white spirit quality screening. According to the method, a standardized evaluation system is constructed through six dimensions of production area, process, safety, sense organ, traceability and detection. The method specifically comprises the following steps: checking geographical indication authentication, verifying a raw material ratio and a fermentation period, detecting aflatoxin and methanol content, evaluating hops, hanging cup and empty cup fragrance retention characteristics, analyzing taste coordination, and detecting key flavor substances through block chain traceability and GC-MS. Different parameter thresholds are set according to different flavors, for example, strong-flavor total ester is larger than or equal to 1.5 g / L, and soy sauce flavor type empty cup fragrance is longer than or equal to 30 minutes. According to the method, HACCP authentication and third-party detection data are combined, so that the problems of high subjectivity and fragmentation of instrument detection in traditional sensory product identification are solved, accurate screening of pure grain solid-state white spirit is realized, and the product credibility and market transparency are improved.

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 invention discloses a laccase HcCotA molecule capable of efficiently degrading aflatoxin B1 and application thereof, and relates to the technical field of microorganisms and microorganism application, and the laccase HcCotA molecule is technically characterized in that HcCotA has excellent thermal stability and pH stability and also has tolerance to pepsin and trypsin, so that the HcCotA keeps enzyme activity in a complex biological environment, and the aflatoxin B1 can be efficiently degraded. The practical application range of the laccase in the field of grain safety guarantee is expanded, the laccase has great economic value and wide market prospect, and key technical support is provided for green and safe development of grain processing and storage industries.

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 relates to a double-signal aptamer sensor and a preparation method and application thereof, and belongs to the technical field of sensors. The dual-signal aptamer sensor comprises a first compound, a second compound and a third compound, wherein the first compound comprises Au dimers and functionalized cDNA (complementary deoxyribonucleic acid) modified on the Au dimers; the first compound is Fe3O4 (at) SiO2-CDs, and the second compound is Fe3O4 (at) SiO2-CDs and an aptamer apt of aflatoxin B1, wherein the aptamer apt of aflatoxin B1 is modified on the Fe3O4 (at) SiO2-CDs; the Fe3O4 (at) SiO2-CDs comprise Fe3O4 (at) SiO2 and CDs which are modified on the Fe3O4 (at) SiO2; the first compound and the second compound are connected through complementary base pairing to form an assembly. Due to the introduction of the Raman signal probe, the Raman signal of the assembly is enhanced, meanwhile, the Au dimers have a quenching effect on the fluorescence of the magnetic substrate, and the fluorescence signal of the assembly is weakened. After the target is added, the aptamer is preferentially specifically combined with the target, the assembly is disassembled, the Au dimers fall off from the Fe3O4 (at) SiO2-CDs, and through magnetic separation, a Raman signal of precipitation is reduced along with the addition of the target, and a fluorescence signal is recovered. The dual-mode detection is realized by measuring the change of Raman and fluorescence signals of the precipitation part along with the target addition amount.

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.