9 results about "Plate count" patented technology

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 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 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 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.