141 results about "Salmonella Be" patented technology

The present invention is directed to mutant Salmonella sp. having a genetically modified msbB gene in which the mutant Salmonella is capable of targeting solid tumors. The present invention further relates to the therapeutic use of the mutant Salmonella for growth inhibition and/or reduction in volume of solid tumors.

The present invention is directed to mutant Salmonella sp. having a genetically modified msbB gene in which the mutant Salmonella is capable of targeting solid tumors. The invention is also directed to Salmonella sp. containing a genetically modified msbB gene as well as an genetic modification in a biosynthetic pathway gene such as the purI gene. The present invention further relates to the therapeutic use of the mutant Salmonella for growth inhibition and/or reduction in volume of solid tumors.

The invention discloses a salmonella sensor, a preparation method and a detection method of salmonella concentration. The salmonella sensor comprises an electrolytic tank, an electrolyte which is arranged in the electrolytic tank, an organic electrochemical transistor which is arranged in the electrolytic tank and a gate electrode which is arranged in the electrolytic tank, wherein the organic electrochemical transistor comprises a substrate, a source electrode and a drain electrode which are arranged on the substrate and an organic semiconductor film layer which coats the substrate and connects the source electrode and the drain electrode; a photoelectric active semiconductor material modifies the gate electrode as a sensitive function layer of the sensor; and an antibody combined with salmonella is fixed on the gate electrode modified by the photoelectric active semiconductor material. The salmonella sensor disclosed by the invention has extremely high sensitivity and extremely low detection limit, and is simple and easy to microminiaturize. The detection method of salmonella concentration based on the salmonella sensor can realize fast and simple high-sensitivity salmonella concentration detection.

The invention relates to the puffed pet food field, and especially relates to a puffed pet food which is capable of being added by a plurality of nutrients. The invention also relates to a production method of the puffed pet food, and especially relates to a production method of the puffed pet food which is capable of being added by a plurality of nutrients. According to the invention, a first purpose of the invention is to provide the puffed pet food having a plurality of vitamin, protein and fat, the puffed pet food supplements simple fat and is rich in a plurality of nutritional elements. According to the invention, a second purpose of the invention is to provide the production method of the pet food, various harmful substances such as mould and salmonella is removed and killed during the production method, thereby the security of the pet food is guaranteed. For the method, the high temperature three-segment disinfection is employed, thereby the microbial pathogens problem is comprehensively solved; the vitamin with high temperature resistance is ingeniously added, the nutrition can be guaranteed, and the food safety is guaranteed.

The present invention relates to the technical field of microorganism ability verification, and discloses a microorganism ability verification salmonella sample preparation method. According to the method, salmonella is adopted as target bacteria, and Serratia marcescens, Citrobacter freundii and Escherichia coli are adopted as interference bacteria; the method comprises: (A) strain resuscitation and amplification; (B) strain isolation; (C) bacterial suspension preparation; and (D) freeze-drying and packaging; and the prepared samples comprise a simple-level negative sample, a simple-level positive sample, an intermediate-level negative sample, an intermediate-level positive sample, a difficult-level negative sample and a difficult-level positive sample, wherein the sample having the same level are subjected to paired use. According to the present invention, the sample prepared through the method has the good stability, the strain survival rate is high, and the reasonable level standards with different difficulties are provided.

The invention provides a detection method of food-borne pathogenic bacteria salmonella. A detection kit comprises recombinase polymerase amplification primer pairs and probes used for detection of food-borne pathogenic bacteria salmonella, and the sequences of the primer pairs are represented by SEQ ID NO:1-3. The detection method used for rapid detection of food-borne pathogenic bacteria salmonella is invented based on molecular biology, is capable of realizing safe, specific, rapid, sensitive, simple, on-site detection of salmonella, avoiding problems of conventional detection technology, is especially suitable for on-site detection, can be used for inhibiting salmonellosis epidemic situation effectively in time, and improving food safety guarantee system.

The invention relates to an inert carrier salmonella and potential application thereof. The inert carrier salmonella is expected to be developed into a novel inert carrier bacterium. The inert carriersalmonella can be applied to development of an indirect agglutination test detection method for conveniently and rapidly detecting an antigen or an infection antibody. The inert carrier salmonella ispreserved at the China General Microbiological Culture Collection Center (CGMCC) at present, the preservation address is Beijing, China, the preservation number is CGMCC No.17340, the preservation date is March 18th, 2019, the classification name is Salmonella sp., and the strain number is S9. The salmonella is separated from a healthy chicken flock, the inert carrier is characterized in that bacteria under the high working concentration and serum of various chicken sources under different genetic backgrounds are not subjected to any macroscopic agglutination reaction, in other words, the bacteria and the chicken source serum are not subjected to a nonspecific agglutination reaction, and the salmonella is named as the inert carrier salmonella. The inert carrier salmonella and the potential application thereof are used for developing the novel convenient and rapid indirect agglutination detection method.

The invention discloses an attenuated Salmonella pullorum and application thereof. By using gene knockout technology, the in vivo colonization gene and the main virulence gene of Salmonella pullorum are deleted, thus obtaining an dual-gene-deleted attenuated Salmonella pullorum SM091-DED strain; and the microbiological preservation number of the strain is CGMCC NO.4604. The virulence of the attenuated Salmonella pullorum disclosed by the invention is obviously reduced, and the in vivo colonization time is short after the attenuated Salmonella pullorum is inoculated into a host; the herd infection test shows that the attenuated Salmonella pullorum has no horizontal transmission capability; the attenuated Salmonella pullorum provides full cross protection for homotype and allotype high-virulence Salmonella pullorum; and after SPF (Specific Pathogen Free) chicks are immunized, the infection of the high-virulence strain can be effectively eliminated, and the herd infection can not be caused. Thus, the invention provides a safe, fine-immunogenicity and low-virulence Salmonellosis avium attenuated live vaccine for preventing Salmonellosis avium.

The application provides a series G-quadruplex-heme DNA enzyme label-free signal amplification method based on rolling-circle amplification. The series G-quadruplex-heme DNA enzyme label-free signal amplification method comprises the steps of: 1) using affinity eluent and a biotinylated capture probe to treat functional microballs of streptavidin to obtain pretreated microballs; 2) cyclically amplifying and purifying the sample genomic DNA to obtain cyclic DNA; 3) mixing the pretreated microballs obtained in step 1) and the prepared cyclic DNA obtained in step 2) and then amplifying them in the rolling-circle to obtain rolling-circle amplification products; 4) mixing the rolling-circle amplification products with the heme to obtain the rolling-circle amplification products with signals amplified, and forming an amplified detection signal by the rolling-circle amplification products with signals amplified. In the step 1) and step 2) there is no time sequence. The detection limit of salmonella is 0.03 pmol/L, the detection cost is low, the operation is simple, the sensitivity is extremely high, the detection is rapid, and whether the salmonella is contained in the sample can be judged by the naked eye.

The invention provides a method for detecting food-borne pathogenic bacteria on the basis of a metal organic framework material and aptamer fluorescence sensor. The fluorescence quenching characteristic of a metal organic framework material and the adsorbability of the framework material to aptamer are utilized, when the aptamer marked by a fluorescence probe is adsorbed to the metal organic framework material, fluorescence of the probe is quenched, a target bacterium is added into a system, the aptamer marked by the fluorescence probe leaves the metal organic framework material and is combined with the target bacterium to enhance fluorescence signals of the probe, and by means of the combination with high appetency and a high specific recognition ability of the aptamer, the method is constructed. Salmonellas are used as model analyte, the fluorescence intensity of the probe and the logarithm of target bacterium concentration form a good linear relation, the linearity range is 18-3.2*10<4> cfu/mL, the detection limit is 5 cfu/mL (S/N=3), the relative standard deviation (RSD) of standard adding experiments ranges from 3.6% to 7.5%, and the recovery rate is within the range of 90.0%-106.0%. The method for detecting the food-borne pathogenic bacteria has the advantages of being accurate, sensitive, high in specificity and the like.

The invention discloses an anti-bacterial film modified by a silver-lysozyme nano-cluster, and belongs to the field of anti-bacterial materials. A preparation method of the anti-bacterial film comprises the following steps: modifying a layer of polydopamine on the surface of a substrate material; then, crosslinking a silver-lysozyme nano-cluster to the surface of the polydopamine through glutaraldehyde to obtain an efficient broad-spectrum antibacterial film material. According to different silver ion contents, the bacteriostasis rate of the anti-bacterial film on salmonella is 51.7 to 100 percent, and the bacteriostasis rate on staphylococcus aureus is 69.5 to 100 percent. In the anti-bacterial film, a substrate is modified by the silver-lysozyme nano-cluster, so that the stability of nano-silver is enhanced by adding lysozyme, the using amount of the silver is lowered greatly, the toxicity is lowered, the cost is controlled, and the reusing rate of the film is increased. The anti-bacterial film can be applied to preparation of food packaging materials and surface anti-bacterial films of medical anti-bacterial instruments.

The invention relates to the technical field of molecular biology, and in particular, relates to a biosensor and method for detecting salmonella. The biosensor includes an RPA reaction reagent, a Lambda nucleic acid exonuclease cutting reaction reagent, an HCR reaction reagent and a chromogenic reagent. A double-stranded nucleic acid of salmonella is amplified by a multi-enzyme system, and dsDNA phosphorylated at the 5' end is obtained. 5'-phosphorylated strands in the dsDNA are digested by Lambda exonuclease, and RPA products become single strands. A universal junction is exposed, an HCR reaction is initiated, and released G-tetrad binds to Hemin to form G4 DNAzyme, colorless TMB is catalyzed to be oxidized into blue oxTMB visible to naked eyes by H2O2, and then salmonella is detected through the change of color and absorbance value. The biosensor has the advantages of visualization, versatility, rapidity and high sensitivity.

The invention provides a Peptocin antibacterial peptide separated from heterometrus spinifer and obtained through a chemical synthesis method. The antibacterial peptide has a remarkable antibacterial effect on clinically-separated multi-drug resistant acinetobacter baumannii, and can be used for efficiently inhibiting the growth of the drug resistant acinetobacter baumannii; and meanwhile, human red blood cell toxicity tests also show that the antibacterial peptide is small in toxicity and can be applied to the preparation of drugs for treating or preventing diseases caused by the drug resistant acinetobacter baumannii and particularly to the preparation of drugs for treating serious infectious diseases such as ventilator-associated pneumonia, septicemia, meningitis, otitis media, skin soft-tissue infection, urinary system infection, central nervous system infection and the like caused by the drug resistant acinetobacter baumannii. The antibacterial peptide provided by the invention is remarkable in inhibiting effect on gram bacteria, unique in antibacterial mechanism and low in toxicity, and can also be applied to the preparation of drugs for treating or preventing diseases caused by micrococcus luteus, salmonella and other gram bacteria.

The invention belongs to the field of microorganisms, and in particular relates to a method for eliminating multi-copy plasmid in salmonella by using a suicide vector, and application of the method. According to the method, the multi-copy plasmid in the salmonella is eliminated by using an exogenous suicide vector. The whole process is simple, rapid, stable and efficient. A basis is made for studying functions of the plasmid.

The present invention relates to an attenuated mutant strain of Salmonella comprising a recombinant DNA molecule encoding a VEGF receptor protein. In particular, the present invention relate to the use of said attenuated mutant strain of Salmonella in cancer immunotherapy.

The invention provides a salmonella detection primer group, a salmonella detection method and a salmonella detection kit based on an RPA-LbCas12a-TTECDS system, and relates to the field of salmonella detection. Based on the combination of a recombinase polymerase amplification technology and a CRISPR gene detection technology, salmonella is detected through an optimized and modified crRNA double-target gene combination, crRNA is screened and optimized aiming at an invA gene and a fimY gene of the salmonella respectively, and upstream and downstream primers for RPA reaction are designed according to nucleotide sequences at two ends of a matched sequence of the crRNA, so that the primer group is obtained. According to the primer group and the crRNA, the RPA-LbCas12a-TTECDS system is designed, and t hesalmonella detection method and kit are established according to the system. The detection method and the kit provided by the invention are used for detecting actual samples, and have the advantages of strong specificity, rapid detection, high sensitivity and high precision.

The invention belongs to the genetic engineering field, in particular relates to a foot and mouth disease virus inhibitor which is designed by adopting RNAi technology and a preparation method and application thereof. The inhibitor is a recombinant live bacterial vaccine containing plasmid for expressing siRNA of foot and mouth disease virus and uses attenuated salmonella suipestifer as recipientbacterium. The recombinant live bacterial vaccine of the invention is convenient to store and use. The inhibitor can be given by injection as well as by mouth. The attenuated salmonella is used as carrier to transfer the expression plasmid of siRNA so that the organism can resist the targeting virus of siRNA and can also resist the infection of salmonella.

The invention discloses a quick detection method by using an interior label and taking a sigD/sigE gene of salmonella as a target through reverse transcription fluorescent quantitation PCR (Polymerase Chain Reaction). In the quick detection method, an RNA (Ribonucleic Acid) interior label obtained by PCR amplification for three times is composed. In addition, the invention further provides a corresponding kit and application. The method disclosed by the invention can be widely applied to the fields such as research of laboratories, food safety and health and hygiene. The phenomenon of false negative missed detection can be avoided, so that the PCR amplification is effectively monitored; in addition, the detection specificity of salmonella is strong, so that dead bacteria and live bacteriacan be effectively distinguished; the quickness and high detection sensitivity are obtained; and the method can be applied to high-throughput screening of the salmonella in the food.

The present invention discloses a salmonella constant-temperature gene amplification fast detecting reagent kit and the method thereof, the reagent kit comprises the primer mixed liquid, the Bst DNA polyase, the reacting liquid, the sample pretreating liquid, the color developing agent, the positive comparison and negative comparison, wherein the sequence of the primer is the sequence such as SEQ ID NO.1, SEQ ID NO.2, SEQ ID NO.3 and SEQ ID NO.4. Through extracting the salmonella genome DNA, constant-temperature gene amplification reaction and judging the reaction product result with the reagent kit the high-specificity, quick, high-sensitivity and simple detecting to the salmonella is realized.