15 results about "Plate count" patented technology

The present application discloses a method and system for evaluating the freshness of fish meat, belonging to the field of fish meat detection, including: obtaining the T2 relaxation curve data of fish meat; using the non - negative least squares method (NNLS) to invert the T2 relaxation curve data to obtain the T2 distribution spectrum data of fish meat; dividing the T2 distribution spectrum data into three regions T21, T22 and T23 according to the T2 value; respectively calculating the characteristic parameters of the T21 region, the T22 region and the T23 region to obtain the nuclear magnetic resonance characteristic data of fish meat; using the plate count method to determine the total number of colonies of fish meat, and taking the total number of colonies as the microbial value data for evaluating the freshness of fish meat; using the nuclear magnetic resonance characteristic data as the independent variable and the microbial value data as the dependent variable, and using the partial least squares method (PLSR) to construct a regression model to obtain a fish meat freshness evaluation model for evaluating the freshness of fish meat. Aiming at the low non - destructive evaluation accuracy of fish meat freshness in the prior art, the present application improves the non - destructive evaluation accuracy.

The invention relates to the technical field of water quality detection, and discloses a method for rapidly detecting AOC in water based on a flow cytometry and application of the method. The method comprises the following steps: (1) respectively and sequentially carrying out low-nutrition domestication and culture on two test bacteria P17 and NOX to obtain a P17 bacterial solution and an NOX bacterial solution; (2) making a standard curve by successively inoculating two test bacteria of P17 and NOX; and (3) determining the concentration of AOC in the water sample: determining the concentration of AOC in the water sample by using the KP17 and the KNOX. The method provided by the invention is obviously superior to a common nonlinear discrete trend in a traditional P17 / NOX plate counting method, ensures reliable association between strain growth and cell counting under different carbon concentration conditions, and has good reproducibility and anti-interference capability.

The invention discloses an intracellular nucleic acid quantification method taking stable isotope labeled escherichia coli as an internal standard, which comprises the following steps: preparing stable isotope labeled escherichia coli, adding the stable isotope labeled escherichia coli as the internal standard into a sample to be detected, and extracting intracellular nucleic acid; the number of internal standard bacteria is determined through a plate counting method, the copy number of single copy genes of the internal standard bacteria in the extracted nucleic acid is detected through real-time fluorescent quantitative PCR, and the intracellular nucleic acid recovery rate is calculated; after the extracted nucleic acid is subjected to enzymolysis, monomers which are not labeled by isotopes are quantitatively analyzed by adopting a liquid chromatography-tandem mass spectrometry technology, and the concentration of the extracted nucleic acid is obtained; and finally, calculating the actual concentration of the intracellular nucleic acid in the sample by combining the extraction concentration and the recovery rate. By introducing the stable isotope labeling internal label, the problem of variability in the extraction process of the intracellular nucleic acid is effectively solved, and the bottleneck of accurately quantifying the concentration of the intracellular nucleic acid is broken through.

The invention discloses a preparation method of lactobacillus rhamnosus 1.0320 metagen, and belongs to the technical field of microorganisms. The invention relates to a preparation method of lactobacillus rhamnosus 1.0320 metagen, which comprises the following steps: (1) inoculating lactobacillus rhamnosus 1.0320 into a high-pressure sterilized liquid culture medium according to the inoculum size of 2% (v / v), culturing and centrifuging, collecting thallus precipitate, washing with a phosphate buffer solution with the pH value of 7.2, re-suspending in a PBS buffer solution with the pH value of 7.2, and preparing 1 * 10 < 7 > CFU / mL bacterial suspension through plate counting; and (2) carrying out ultrasonic treatment on the bacterial suspension prepared in the step (1) at the ultrasonic power of 400 and 800 W for 10-60 minutes, and freeze-drying to obtain the metagen of the lactobacillus rhamnosus 1.0320. The lactobacillus rhamnosus 1.0320 prepared by the preparation method disclosed by the invention has the advantages that the surface hydrophobicity and the oxidation resistance of the metagen are obviously improved, and the lactobacillus rhamnosus 1.0320 has a good anti-inflammatory characteristic.

The invention discloses a quantitative counting method for biochar-loaded microorganisms. The method comprises the following steps: 1) centrifuging a to-be-detected bacterial liquid of biochar-loaded microorganisms, and determining the free bacterial concentration of the supernatant bacterial liquid by adopting a plate counting method; (2) cleaning and drying the biochar loaded with microorganisms, measuring the mass of the biochar, adding normal saline for the first time, oscillating, centrifuging, taking supernatant liquid, counting by adopting a plate counting method, and recording a counting result as A1; adding normal saline into the centrifugal tube without the supernatant for the second time, shaking, centrifuging, taking the supernatant, counting, and recording the counting result as A2; and performing result verification according to the following a)-c) to obtain the quantitative count of the to-be-detected bacterial liquid of the biochar-loaded microorganisms: when A2lt is greater than or equal to 0 and smaller than 5% A1, the count is A1, when A2 is greater than or equal to 5% A1 and smaller than or equal to 20% A2, the count is A1 + A2, when A2gt is greater than or equal to 5% A1 and smaller than or equal to 20% A2, the experimental result is inaccurate, and redetermination is needed. The method effectively solves the problems of bacterial loss, free bacterial interference, low desorption and adsorption efficiency and the like in the traditional technology.

The invention relates to the technical field of organic bacterial manure, in particular to a preparation method and device of aerobic fermentation organic bacterial manure, and the preparation method comprises the following steps: S1, a worker adds materials into the preparation device of the aerobic fermentation organic bacterial manure; s2, a worker mixes the materials with aerobic fermentation strains through a preparation device of the aerobic fermentation organic bacterial fertilizer; s3, after the materials are fermented for 23-27 days, a worker detects the obtained fermentation liquor through a microscope counting method or a plate counting method, and the concentration of compound bacteria in the fermentation liquor is detected; and S4, judging that the fermentation of the fermentation liquid meeting the thallus concentration is completed, thereby obtaining the liquid organic bacterial fertilizer. According to the preparation method and device of the aerobic fermentation organic bacterial fertilizer, the stirring mechanism is arranged, materials and oxygen can be fully mixed through the stirring mechanism, then the fermentation efficiency can be improved, the detection mechanism is arranged, the temperature in the fermentation barrel can be detected through the detection mechanism, and then the temperature can be controlled through the temperature control layer.

The method for evaluating the vibrio parahaemolyticus VBNC state in the digestive tract in vitro comprises the following steps that simulated gastric juice and vibrio parahaemolyticus bacterial liquid are added into a centrifugal tube, test groups 1, 2 and 3 without glucose are set to be 2.5, 3.5 and 4.5 in pH value and test groups 4, 5 and 6 with the pH value being 2.5, 3.5 and 4.5 and 4 g of glucose are set to be 2.5, 3.5 and 4.5 respectively, after constant-temperature shaking bath culture is carried out for 120 min, simulated intestinal juice is added, then culture continues to be carried out for 120 min, and the vibrio parahaemolyticus VBNC state in the digestive tract is obtained. The simulated digestive juice is extracted at 30 min, 60 min, 120 min and 240 min, a plate counting method, PMAxx-qPCR, flow cytometry, ATP detection, SEM observation and cell membrane permeability detection are conducted on the simulated digestive juice, and the growth and metabolism conditions of the vibrio parahaemolyticus in the digestive tract and the condition that the vibrio parahaemolyticus enters the VBNC state are evaluated; therefore, rapid and systematic evaluation of the vibrio parahaemolyticus in the digestive tract is realized.

The invention discloses a method for measuring the total number of plate bacterial colonies and application of the method. The determination method comprises the following steps: preparing a plate counting culture medium, and carrying out water bath heat preservation on the plate counting culture medium; the plate counting culture medium contains peptone, yeast extract powder, glucose, agar, sodium pyruvate, L-cysteine hydrochloride, magnesium sulfate and hemin; performing gradient dilution on the target bacteria; fully and uniformly mixing the sample homogenate with a plate counting culture medium; covering the surface of the solidified plate counting culture medium with a layer of same plate counting culture medium to form a covering layer; carrying out constant-temperature culture on the solidified flat plates with various dilution degrees; when macroscopic bacterial colonies are formed in the culture medium plate, selecting a plate with 30-300 bacterial colonies on each plate for counting. The method does not need coating operation, can effectively reduce the pollution risk, shortens the detection time, has clear colonial morphology and reliable data, and is suitable for rapid determination of the total number of colonies in various samples.

The invention discloses a method for rapidly determining the concentration of a bacterial solution based on a pH value, and relates to the technical field of microbiological detection, and the method comprises the following steps: S1, establishing a standard curve: selecting a target strain, preparing standard bacterial solutions with at least five gradient concentrations, with the standard bacterial solution concentration range of each gradient concentration being 103-109 CFU / mL, and the ratio of the adjacent gradient concentrations being 10; and respectively placing the standard bacterial solutions with various gradient concentrations in a sterile reaction container, and culturing for 2-4 hours under the constant-temperature oscillation conditions of 35-37 DEG C and 180-220 r / min. According to the method, the detection period of 48-72 hours of a traditional plate counting method is shortened to 2-4 hours, the detection efficiency is improved by 10 times or more, the requirements of scenes such as rapid screening of antibacterial materials, real-time monitoring of a food production line and emergency microorganism detection can be met, the detection period is greatly shortened, and the working efficiency is improved.

The invention discloses a machine learning-based bacterium culturability rapid diagnosis method, which comprises the following steps: S1, amplifying bacteria in a culture medium, and determining the culturability of a bacterium sample through a heterotrophic plate counting method to obtain a culturable bacterium sample; s2, observing a bacterial sample through a QPI microscope, and extracting characteristic parameters of bacteria by utilizing automatic image processing to obtain a bacterial parameter data set; s3, preprocessing the bacteria parameter data set, wherein preprocessing comprises abnormal data removal, repeated data removal and culturable label labeling; s4, constructing a bacterial culturability classification and diagnosis model based on an interpretable machine learning model, and performing rapid diagnosis on the culturability of the bacteria in an actual water sample by using the trained bacterial culturability classification and diagnosis model by taking the data set obtained after pretreatment in the step S3 as an input variable; according to the method, the time for judging the culturability of the bacteria is remarkably shortened while the diagnosis accuracy is ensured.

The utility model relates to the technical field of paper dinner plate counting, in particular to an efficient paper dinner plate counting device which comprises a workbench, a paper dinner plate bracket, a motor, a rotating rod, a driving wheel, a synchronous belt, a driven wheel, a bearing arm plate, a bearing seat, an air cylinder and a counting sensor. When the motor drives the rotating rod to rotate, the bearing arm plate can drive the bearing seat to rotate, the suction cup sucking the paper dinner plate moves upwards, rightwards and downwards, light beams emitted by the counting sensor are shielded by the paper dinner plate in the upward process, and the counting sensor generates corresponding electric signals for efficient counting. Therefore, the stacked paper dinner plates are automatically counted, the accuracy and availability of data are improved, the input cost can be effectively reduced by adopting the counting sensor, and the practicability is higher.

The invention relates to the technical field of industrial automation and logistics, and provides a plate counting and transporting method based on visual inspection, and the method comprises the steps: collecting a detection video of a plate entering a current loading layer of transportation equipment through a camera in a stacking process; according to the detection video, whether the front edge of the plate reaches a preset position or not is judged through the pixel difference value of the plate edge and the main body, and if the front edge of the plate reaches the preset position, the number of the successfully stacked plates is automatically updated; whether the number of the successfully stacked plates reaches a preset number or not is judged, and if yes, stacking completion prompt information is automatically generated; and if it is judged that the plates do not arrive at the current loading layer, the lifting mechanism is automatically controlled, and all the stacked plates are made to synchronously move by a standard interlayer distance in the direction away from the current loading layer. According to the invention, the risk of sliding, collision or subfissure damage of the plates in the subsequent stacking and transporting process is reduced, errors possibly generated by manual counting are avoided, and the loading efficiency is greatly improved.

The invention relates to the technical field of data analysis, particularly discloses a microbial colony quantitative analysis method based on fusion of conductance change and a TOC (Total Organic Carbon) model, and aims to solve the problems that a traditional plate counting method is time-consuming and large in manual error, an existing automatic method is easy to interfere and ignores carbon dioxide dynamics, and a single data source method is poor in robustness. According to the method, a multi-source input vector is formed by collecting a microbe sample conductivity difference value, carbon dioxide concentration and temperature and humidity in real time, the conductivity difference value is mapped into a carbon base number value through a TOC algorithm, microbe quantity characteristics are extracted in combination with machine learning, microbe quantity probability distribution is obtained through Kalman filtering smoothing and state estimation and Gaussian process regression, and the microbe quantity probability distribution is calculated. Outputting a bacterial colony equivalent and a confidence interval, and verifying and ensuring the accuracy by using sterilized sucrose. A closed-loop mechanism is verified through sterilized sucrose, the accuracy of quantitative analysis results is further ensured, and the problem of deviation caused by neglecting the dynamic nature of carbon dioxide in an existing method is effectively solved.

The invention discloses a method for quantitatively detecting five kinds of lactobacillus PMA-qPCR viable bacteria based on novel molecular target primers. The molecular target is as shown in SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3 and SEQ ID NO. 4. Compared with the prior art, the method has the advantages that viable count of single lactobacillus in a compound probiotic product can be achieved, the method has the advantages of being short in detection time, good in specificity, easy to operate and the like, a dye method and a probe method are established at the same time, and the method has a wider application scene and can better meet market requirements. Meanwhile, the counting method provided by the invention also overcomes the defects that the existing molecular detection method and plate counting method cannot distinguish the dead and live bacteria and cannot count the live but non-culturable bacteria, the counting result is more accurate, and the method is higher in practicability.

The electrochemical sensor for detecting the total number of water bacteria colonies and its preparation method and application belong to the technical field of water detection. In order to solve the technical problems of long time consumption, inability to detect VBNC bacteria, lack of general target for detection, etc. in the existing water bacteria colony number detection method, the present application constructs an ultra-sensitive electrochemical sensor based on a triple signal amplification strategy by screening a general nucleic acid target fragment for water bacteria colony number detection, designing a corresponding hairpin probe and a hairpin structure capture probe. The sensor can realize rapid determination of the total number of water bacteria colonies, has good anti-interference, reproducibility and stability, can realize high-sensitivity detection of bacterial 16S rRNA gene, the linear range is 0.1 fM to 100 pM, the detection limit is as low as 1.0 aM; at the same time, it can realize actual detection of bacteria as low as 1 CFU / mL, and the detection result is highly consistent with the plate counting method, which is the "gold standard" for water bacteria colony number detection.