56 results about "Escherichia coli detection" patented technology

The invention discloses a chromogenic medium used for detecting esherichia coli O157:H7. The medium comprises agar, peptone, beef extract powder, sodium chloride, sorbitol, inositol, neutral red, beta-galactosidase chromogenic substrate, beta-glucuronidase chromogenic substrate, isopropyl-beta-D- thiogalactopyranoside, natrium taurocholicum, potassium tellurite and cefixime. The chromogenic medium used for detecting esherichia coli O157:H7 of the present invention has the advantages of high sensitivity, good specificity, direct bacterial strain discrimination according to colony color, short detection period and strong operationality, is suitable for treating high-reflux samples, is capable of comprehensively, systematically and accurately detecting and preliminarily identifying the esherichia coli O157:H7 in food production and environment, and provides a novel approach for rapidly detecting the microbes.

The invention discloses a CPA primer, kit and detection method for escherichia coli O157:H7. The CPA primer designed for a target rfbE comprises stripping primers 4s and 5a, a crossing amplification primer 2a1s and specific primers 2a and 3a; the nucleotide sequences of the primers are shown as SEQ ID NO.1-NO.5 respectively. A crossing priming amplification reaction detection and identification system designed for specific target sequences rfbE and stx1 of E.coli O157:H7 overcomes the defects of long required cycle, low sensitivity, high cost and difficult field application of methods in the prior art. By selecting a conserved region of the specific sequences rfbE and stx1 of a target strain, a pair of stripping primers, the crossing primer and the specific primers are designed to construct the crossing priming amplification reaction system, and a detection result is obtained within about 60 minutes to shorten the traditional cycle for detecting escherichia coli.

The invention relates to bacterium detecting equipment and particularly discloses an online analyzer of Escherichia coli, and the online analyzer comprises a constant temperature box and a sampling pump, wherein a temperature sensor, a heating device, an analyzer mainboard, a culture dish and a fluorescence spectrophotometer are arranged in the constant temperature box; a display is arranged outside the constant temperature box; the analyzer mainboard is electrically connected with the temperature sensor, the heating device, the fluorescence spectrophotometer and the display; and the outlet of the sampling pump is in pipe joint with the culture dish, and the inlet of the sampling pump is connected with an external sample pipe. The online analyzer disclosed by the invention can be used for realizing the automation and integration of the functions such as the sampling, culturing, analyzing, displaying and the like of the Escherichia coli detection, has the advantages of high detection sensitivity, high detection speed, low cost, no secondary pollution, small maintenance amount and low operation cost and can be used for realizing the automatic online analysis and monitoring of the Escherichia coli.

The invention relates to a detection method belonging to the technical field of environmental detection, in particular to a method for detecting toxicity of nanomaterials in the environment by adopting Escherichia coli containing green florescent protein plasmids. The method overcomes the interference of a few natural organic matters existing in the environment with the detection of toxicity of the nanomaterials so that the detection of toxicity of the nanomaterials is more convenient and accurate. The specific method selects the Escherichia coli transforming the green florescent protein plasmids as the bacterium for detection and comprises the following steps: 1. using an M9 culture medium to prepare bacterial suspension of the Escherichia coli containing the green florescent protein plasmids; 2. using ultrasonic dispersing nanomaterials to prepare suspension of nano particulate matters; and 3. culturing the nano particulate matters and the bacterial suspension of the Escherichia coliat 37 DEG C, using an enzyme-labeling instrument to detect the change of the florescence intensity of the nano particulate matters in certain period and judging the toxicity of the nano particulate matters to the Escherichia coli according to the difference of the change of the florescence intensity. The invention provides the efficient and stable detection method of toxicity of the nanomaterialsand the method is not likely to be interfered by other factors and is simple and low in cost.

The invention provides a diarrheogenic escherichia coli detection kit and a detection and typing method thereof, which are suitable for the technical field of molecular biology and microbiological detection. The detection kit comprises a PCR (Polymerase Chain Reaction) buffer solution, MgC12, dNTP, DNA (Deoxyribonucleic Acid) polymerase, primers of stp, sth, lt, aggR, eaeA, escV, stx1, stx2 and ipaH genes, probes SEQ ID NO:1-SEQ ID NO:27 and a Homo-tag the sequence of which is SEQ ID NO:28. The detection and typing method comprises the following steps of: obtaining and processing a sample, and adding the processed sample to a detection kit; carrying out fluorescent quantitative PCR reaction; and obtaining a detection result. The detection and genotyping method provided by the invention has the advantages of good specificity, high sensitivity, simple and convenient operation, easiness in identification of the result and is suitable for rapid screening and genotyping of diarrheogenic escherichia coli.

The invention provides an escherichia coli detection kit which comprises two pairs of primers designed by using fliC genes of the escherichia coli as target genes on the basis of a loop-mediated isothermal amplification (LAMP) technology: inner primers FIP/BIP and outer primers F3/B3. The escherichia coli detection kit has the advantages of more comprehensive detection effect and low omission ratio.

The invention discloses a coli group and colibacillus testing medium which is prepared by dissolving 20 grams of peptone, 5 grams of lactose, 2 grams of bile salt, 1.5 grams of monopotassium phosphate, 4 grams of monopotassium phosphate, 5 grams of sodium chloride, 0.1 gram of 5-bromo-4-chloro-3-indole galactoside, 0.1gram of 4- methylumbelliferone glucuronide, 1 gram of aspartic acid, 0.5 gram of casamino acid, 1 gram of yeast extracts and 20 grams of agar in 1000ml of deionized water, and the coli group and colibacillus testing medium is not only used as a plate medium, can also be used as an analoids form, and is low in cost and convenient to popularize and use.

The invention discloses a multistage nano golden flower, a preparation method and an application thereof. According to one embodiment, the preparation method comprises the steps of fully mixing chloroauric acid and poly diallyldimethylammonium chloride in an aqueous system, continuously stirring at room temperature until a prepared mixed solution is yellow, then adding ascorbic acid to the obtained yellow mixed solution, violently stirring, then adding a nano golden ball, quickly stirring, and then standing at room temperature. The preparation method has the advantages of simplicity, easiness in operation, good controllability and high productivity, a nano tip bulge is formed on the surface of the obtained multistage nano golden flower, and the multistage nano golden flower has a large specific surface area. The nano golden flower can be used as a gold-labelled antibody of an immunochromatographic strip, so as to be applied to the field of food safety, environment, medical diagnosis and the like, simple and high-sensitive analysis and detection can be performed on target objects, for example, high-sensitive detection of colibacillus can be performed, and the lower limit of the detection concentration reaches 103 CFU/mL.

The invention relates to a preparation and detection method of an electrochemical biosensor for escherichia coli, belonging to the field of biomedicine. The invention provides a preparation method andapplication of a D-mannose-dopamine-chitosan modified electrochemical biosensor based on Fc-Ru < 3 + > mediation of a double-electron mediator . A sensor comprises an electrode material, surface filmmodification of an electrode, an immobilized bioactive compound and the double-electron mediator, and the electrode material is glassy carbon. The electrode surface film is a dopamine and chitosan film; wherein an immobilized bioactive compound is D-mannose; and a component of the dual-electron mediator is Fc-Ru < 3 + >. The electrochemical sensor has the advantages of high response sensitivity to escherichia coli in a detection system, strong selectivity, good stability and simple preparation, and can be used for escherichia coli detection.

A presence/absence test for Staphylococcus aureus (S. aureus) involves placing a first generation test sample in a solution that will clot in the presence of S. aureus. The solution contains components that will selectively grow S. aureus and also contains clotting factors that will react with S. aureus, if S. aureus is present in the sample, to clot the solution. Examples of specimen samples that can be tested include nasal swabs and lesion swabs, among others. The test can also be modified to detect the presence or absence of methicillin resistant S. Aureus (MRSA). The addition of micro particles having a size in the range of about 0.1 micron to about 1.0 mm provides localities where the bacteria agglomerate, thereby significantly decreasing the clotting time, and providing a significantly stronger clot. The micro particles can be used in other bacteria tests to accelerate the production of an end result. Such other tests can include a vancomycin-resistant enterococcus test; a Group B Streptococcus test; a test for hemolytic E. coli; and a test for Listeria monocytogenes, to name a few. These tests are all performed in a liquid broth-type reagent mixture and do not necessarily involve clotting of the broth.

An offshore escherichia coli detection method is provided. According to the method, escherichia coli in seawater is intercepted onto a filter membrane by a suction filtration system, the filter membrane is put into a culture medium and cultured and is a microfiltration membrane having a pore diameter of 0.45 [mu]m, a bile lactose enrichment broth is added into a detection solution to perform bacteria-proliferating operation for 30-48 h, and if the solution is muddy and a gas is generated, it is determined that the escherichia coli is detected. The culture medium is an eosin-methylene blue agar plate, the culture time is 10-12 d, and colony growth conditions of the escherichia coli are observed after culturing. If a typical escherichia coli colony grows and is separated from the eosin-methylene blue agar plate, it is determined that the escherichia coli are detected. Compared with traditional microbe detection methods, the method is low in cost, rapid, convenient, simple, and high in sensitivity.

The invention discloses a CRISPR/Cas12a-RCA electrochemical sensor detection system and application thereof. According to the present invention, the CRISPR/Cas12a-RCA electrochemical sensor detection system can be used for the detection of Escherichia coli O157: H7, has characteristics of simple operation and low cost, can accurately distinguish Escherichia coli O157: H7 from different bacteria, and has strong detection specificity; the detection concentration range is also wide, a good linear relation is achieved within the range of 10-107 CFU.mL <-1 >, the detection sensitivity is high, the lowest detection limit is 10 CFU.mL <-1 >, and the detection result is accurate and reliable. The detection method is not only suitable for detecting escherichia coli O157: H7 in food, but also has huge application potential in detection of other pathogenic bacteria or clinical diagnosis.

The invention discloses a primer for detecting Escherichia coli, and a method and an application of the primer. The nucleotide sequence of the primer is indicated in SEQ ID NO: 1 and SEQ ID NO: 2, an Escherichia coli detection method is established for the involved primer, and the detection method has the advantages of fine specificity, good sensitivity, rapidness and reliability in detection and simplicity in operation. A kit comprising the primer is designed, and the Escherichia coli is conveniently detected. The specific primer is designed for specific genes LafF of the Escherichia coli and can be used for rapidly, simply, conveniently and accurately detecting the Escherichia coli.

The invention relates to the technical field of microbiological detection, and provides a method for determining the content of escherichia coli in water. The method comprises the following steps: preparation of a silver-escherichia coli system, preparation of a capture probe, addition of nitric acid, preparation of a detection probe, establishment of an escherichia coli detection standard workingcurve, and determination of the content of escherichia coli in water. The invention provides an SERS detection method of escherichia coli. The SERS detection method can be used for specifically, sensitively and quickly detecting the content of escherichia coli in water.

The invention discloses a meat product pressing device for detecting escherichia coli by applying immunology, comprising a pressing mechanism, a horizontal base and a pulley set, wherein the pressing mechanism comprises a box, a first pull rod and a second pull rod, the box is mounted at the middle of the horizontal base, the inner part of the box is horizontally provided with a pressing plate, the left side of the box is provided with a first support, the bottom of the first support is mounted on the horizontal base, one end of the first pull rod is hinged to the middle of the first support, the other end of the first pull rod is provided with a pulling rope, the pulling rope is connected with the pulley set, one end of the second pull rod is hinged to the middle of the upper surface of the pressing plate, and the other end of the second pull rod is hinged to the middle of the first pull rod; one corner of the pressing plate is also provided with escherichia coli test paper. The meat product pressing device has a function of detecting the escherichia coli, is used for judging whether a meat product is polluted or not, and is high in practicability and economic value.