31 results about "Most probable number" patented technology

A Class B biosolids sludge digestion process whereby feed sludge is introduced to a completely-mixed, continuously- or intermittently fed and drawn, sealed, anaerobic digester, and sludge is drawn off at a rate such that the average mean cell residence time for the sludge in the digester is greater than or equal to 10 days, and less than 15 days. The temperature of the sludge is maintained in the thermophilic range to produce treated sludge having: a volatile solids content that is at least 38% less than the volatile solids content of the feed sludge, a reduced fecal coliform content that is at least a 2 log (base 10) reduction from the feed sludge, and where there is no more than 2,000,000 most probable number / gram total solids (dry weight basis) of fecal coliform in the treated sludge.

The invention discloses a quantitative detection method of salmonella living body in water, which adopts a multiple-tube fermentation method to preliminarily screen living bacteria taking salmonella as the principal component from water sample according to the growth characteristics of the salmonella and the conservative property of invA gene. By utilizing universal primers 139 and 141 of the salmonella, the quantitative detection method can be used for distinguishing the positive colony of the salmonella by polymerase chain reaction (PCR) amplification. The quantitative detection method can be used for detecting the salmonella living body in water in a quantitative way by a most probable number (MPN) counting method. The method can accurately detect the content of the salmonella living body in water, is high in specificity as well as simple and convenient to operate, and is suitable for detecting multiple water samples such as surface water, sewage and the like.

A system and method for assessing a supply chain for a perishable product. In various embodiments, the present invention provides a quality code for a perishable product which encodes a plurality of the most important performance metrics of the cold chain for the perishable product, including food quality oriented measures such as cut-to-cool time, transportation quality and accumulated shelf-life loss, and food safety oriented measures such as most probable number range for microorganism growth into a compact, modular and simple to read format.

The invention discloses a coliform single-tube quantitative rapid detection method which comprises the steps: preparing specific detection culture medium; inoculating sample; culturing the inoculated sample for 8-15h at the temperature of 35-44DEG C; centrifugating for 5-10min at the speed of 8000-12000rpm; measuring absorbance value at the part of 405nm of supernate by a spectrophotometer; and calculating bacteria concentration according to formula. The method utilizes the spectrophotometer to measure the absorbance value of culture solution, and is more sensitive than visual evaluation, thus greatly shortening the culturing time. By adopting the single-tube quantitative detecting technique, one simple needs a tube of culture solution, so that a great deal of reagent and consumable materials can be saved compared with most probable number method; furthermore, the detection method is more rapid and stabler, and has high sensitivity.

The invention relates to a ready-to-use culture apparatus for the most probable number detection of a flora. A culture detection tube comprises a main pipe, a gas collection pipe and a pipe cap for sealing the main pipe. The main pipe is of a curved hose structure and is connected with the gas collection pipe. The main pipe, the gas collection pipe and the pipe cap form a sealed chamber, the length of the main pipe is greater than that of the gas collection pipe, and the inner diameter of the main pipe is greater than that of the gas collection pipe. The culture detection tube is the externalgas collection pipe. Compared with a built-in small inverted pipe which is disposed 180 degrees upside down in the prior art, the angle between the gas collection pipe and the main pipe can be flexibly set, which greatly reduces exhausting difficulty.

A sample holding device having a plurality of sample wells. A gutter surrounds the sample wells and is in fluidic communication with an overflow sample well. An upper surface of the device is sealed with a sealing film that fluidically isolates each sample well from each other and from the gutter and overflow well. The device is used to perform a most probable number (MPN) procedure.

Methods and compositions are disclosed for confirming and quantifying the presence of a specific probiotic microorganism in a sample of animal feed. Hybridization and polymerase chain reaction (PCR) techniques are applied to identify the presence of the specific probiotic microorganism in cultures grown in most probable number and serial dilution methods, after calibration of the techniques using blank and control samples.

Methods and compositions are disclosed for confirming and quantifying the presence of a specific kind of microorganism in a sample of material. Hybridization and polymerase chain reaction (PCR) techniques are applied to identify the presence of the specific microorganism in cultures grown in most probable number and serial dilution methods, after calibration of the techniques using blank and control samples. For example, samples of animal feed can be cultured and analyzed to determine the quantity of specific probiotic microorganisms present in the feed.

A precise quantization method for nitrogen cycle of a lake ecosystem includes 1), applying an isotope pairing method to quantitatively research nitrogen migration and conversion of a sediment-water interface of the lake ecosystem; 2), determining release of nitrogen of a water-gas interface by measuring N2O yield by the aid of a closed chamber-gas chromatograph method; 3), measuring biomass of aquatic plants and nitrogen content in bodies of the aquatic plants by the aid of a Dumas method and determining nitrogen absorbed quantity of the aquatic plants; 4), measuring biomass of microorganisms in the ecosystem by the aid of an MPN (most probable number) method, and measuring the effect of the microorganisms in a nitrogen conversion process and conversion quantity of the microorganisms to the nitrogen; and 5), applying the stable isotope technology to measure assimilation of aquatic animals to the nitrogen, and realizing precise quantization of the nitrogen, namely, measuring a food web of the aquatic animals and a trophic-level structure to determine migration and conversion of the nitrogen in the food web. Procedures of the precise quantization method are realized in the same simulation ecosystem.

The invention discloses a coliform single-tube quantitative rapid detection method which comprises the steps: preparing specific detection culture medium; inoculating sample; culturing the inoculated sample for 8-15h at the temperature of 35-44DEG C; centrifugating for 5-10min at the speed of 8000-12000rpm; measuring absorbance value at the part of 405nm of supernate by a spectrophotometer; and calculating bacteria concentration according to formula. The method utilizes the spectrophotometer to measure the absorbance value of culture solution, and is more sensitive than visual evaluation, thus greatly shortening the culturing time. By adopting the single-tube quantitative detecting technique, one simple needs a tube of culture solution, so that a great deal of reagent and consumable materials can be saved compared with most probable number method; furthermore, the detection method is more rapid and stabler, and has high sensitivity.

Methods and compositions detect and quantify viable Legionella. Dip-slides that include an absorbent medium, growth promoting, and growth selective substances are useful in rapid detection and quantification of microcolonies of Legionella. Most probable number method of detection and quantification of Legionella are disclosed.

The invention discloses a preparation method and application of persimmon syrup. By adopting a series of unique preparation processes of harvesting and sorting, washing and crushing, softening and astringency removal, ultra-micro refining, syrup residue separation, low-temperature concentration and the like, the preparation method suitable for mopan persimmons is provided, the persimmon syrup prepared through the preparation method does not contain any additives such as a preservative, a sterilizing agent and a color retention agent, not only are the original flavor characteristics of the mopan persimmons retained, but also the efficacy functions in traditional medicine are maintained, the color of the persimmon syrup is brown orange, the persimmon syrup has the rich persimmon fragrance and is sweet but not oily in taste and free of astringent taste, the total acidity is 54.02 degree T, the viscosity is 542.73 mPa.s, the total number of bacterial colonies (cfu / mL) is less than or equalto 100, and the most probable number of coliform bacteria (MPN / 100mL) is less than or equal to 3; and no pathogenic bacterium is detected, and the persimmon syrup has the wide application value in the processing field of beverages, desserts, ice creams and heal care products.

The invention discloses a quantiative detection method of salmonella in soil and an assay kit thereof. On the basis of taking related researches as reference, the method performs quantitative detection on pathogenic microorganism in the soil by adopting a method of combining MPN (most probable number) with PCR (polymerase chain reaction). By utilizing advantages of quickness and accuracy of the PCR method, biochemical identification, serological identification and other steps of positive results in the traditional MPN method are substituted, so that complex steps in a national standard methodare reduced, the detection efficiency is improved, and a pre-enrichment step in the national standard method is adopted at the same time to improve the accuracy of detection targeting pathogenic bacteria; and due to the complexity of soil, the soil contains massive microorganisms, as well as various pathogenic microorganisms of different items, so that the targeting pathogenic bacteria is selectively cultured to improve the detection efficiency in order to quantitatively detect the targeting pathogenic bacteria better and more accurately. By virtue of creative effort of the inventor and scientific test verification, the sensitivity of the salmonella quantitative detection method in an experiment of adding pure bacteria in the soil is 250 per gram of soil.

The invention discloses a quantitative detection method of salmonella living body in water, which adopts a multiple-tube fermentation method to preliminarily screen living bacteria taking salmonella as the principal component from water sample according to the growth characteristics of the salmonella and the conservative property of invA gene. By utilizing universal primers 139 and 141 of the salmonella, the quantitative detection method can be used for distinguishing the positive colony of the salmonella by polymerase chain reaction (PCR) amplification. The quantitative detection method can be used for detecting the salmonella living body in water in a quantitative way by a most probable number (MPN) counting method. The method can accurately detect the content of the salmonella living body in water, is high in specificity as well as simple and convenient to operate, and is suitable for detecting multiple water samples such as surface water, sewage and the like.

The invention discloses a quantiative detection method of escherichia coli in soil and an assay kit thereof. On the basis of taking related researches as reference, the method performs quantitative detection on pathogenic microorganism in the soil by adopting a method of combining MPN (most probable number) with PCR (polymerase chain reaction). By utilizing advantages of quickness and accuracy ofthe PCR method, biochemical identification, serological identification and other steps of positive results in the traditional MPN method are substituted, so that complex steps in a national standard method are reduced, the detection efficiency is improved, and a pre-enrichment step in the national standard method is adopted at the same time to improve the accuracy of detection targeting pathogenic bacteria; and due to the complexity of soil, the soil contains massive microorganisms, as well as various pathogenic microorganisms of different items, so that the targeting pathogenic bacteria is selectively cultured to improve the detection efficiency in order to quantitatively detect the targeting pathogenic bacteria better and more accurately. By virtue of creative effort of the inventor andscientific test verification, the sensitivity of the escherichia coli quantitative detection method in an experiment of adding pure bacteria in the soil is 25 per gram of soil.