| Description | Inquire | Product introduction： The MA qPCR live bacteria detection kit provides an effective means for detecting bacterial activity. The kit provides a mixture of PMA dye and qPCR based on SYBR Green dye. The optimal amount of dye and the number of samples that can be treated may vary depending on theProduct introduction： The MA qPCR live bacteria detection kit provides an effective means for detecting bacterial activity. The kit provides a mixture of PMA dye and qPCR based on SYBR Green dye. The optimal amount of dye and the number of samples that can be treated may vary depending on the type of sample. PMA is a high-affinity DNA-binding dye, especially with double-stranded DNA. The dye itself has weak fluorescence, but it can emit brighter fluorescence after binding to nucleic acids. PMA is impermeable to cell membranes, so it can selectively modify the DNA of dead cells with damaged membranes. After the PMA-modified DNA is photolyzed by blue light ( ~ 464 nm ), the photoreactive azide group on the PMA is converted into a highly reactive nitrene radical, which reacts with any hydrocarbon near the DNA binding site to form a stable covalent nitrogen-carbon bond, resulting in permanent DNA modification. This modification process will make DNA insoluble and lost with cell debris during the later genomic DNA extraction process. The unbound PMA remaining in the solution reacts with water molecules under strong light irradiation to decompose into hydroxylamine compounds without cross-linking activity, so that it can no longer covalently bind to DNA. Based on this feature of PMA, PMA was combined with qPCR technology to form a new detection method, PMA-qPCR, for the screening of live bacteria. At present, the method has been verified in a variety of bacterial strains, yeast, fungi, viruses and parasites. The treatment of complex samples, such as manure or soil, may require optimization of sample dilution, dye concentration, and light treatment time. The treatment of diluted samples, such as water testing, may require filtration or concentration prior to dye treatment. Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. the components of the kit contain fluorescent dyes. Avoid light during use and storage. 3. for your safety and health, please wear experimental clothes and disposable gloves.Product parameters:Spectral characteristics :PMA: Ex = 464 nm; Ex/Em = 510/610 nm (following photolysis and reaction with DNA/RNA)Component： PMA：Ex = 464 nm; Ex/Em = 510/610 nm (following photolysis and reaction with DNA/RNA) Instruction： Precautions before use： 1.This live bacteria detection kit distinguishes dead bacteria and live bacteria according to cell membrane permeability. Many methods of killing bacteria cause damage to the cell membrane and are therefore compatible with this kit. But some methods, such as ultraviolet irradiation, may not immediately cause cell membrane rupture. Therefore, before selecting this kit, it is necessary to carry out literature search and pre-experiment to determine whether the kit is suitable for the bacterial type and killing method you choose. 2.After PMA treatment, the bacteria need to be photolyzed to covalently bind the dye to dead cell DNA. Photolysis operations can use blue or white light sources. Generally speaking, the brighter the lamp, the higher the efficiency of the photolysis step. Non-LED lamps ( such as halogen lamps ) may heat your sample and have a negative impact on the analysis. Ice is required to cool the sample during irradiation. 3.Sample can be cryopreservation after photolysis. Frozen samples before PMA treatment photolysis may damage the cell membrane and produce false negative results. If the sample needs to be frozen before detection, it is recommended to perform a pre-experiment first. 4.Part of the mechanism of PMA is to remove PMA covalently modified DNA from the sample by precipitation ; therefore, when extracting genomic DNA, it is necessary to use the same volume of genomic DNA eluent for volume normalization. The positive control can use the genomic DNA of living cells. 5.In order to verify the effectiveness of PMA in the test sample, the Ct ( dCt ) changes between- / + PMA can be compared. Experimental materials ( self-provided )：①Light source ( for the photolysis step after PMA modification of DNA ) ; ② Bacterial genomic DNA extraction kit ; ③ effective qPCR primers corresponding to the sample type Experimental procedure： 1.Suck 10 µL of E.coli bacterial solution in liquid LB medium, and culture E.coli in the bacterial incubator overnight or longer to the logarithmic growth phase ( OD600 ≈ 1.0 ) ; Note : The culture time is adjusted according to the experiment. 2.Two portions of live E.coli, 400 µL each, were placed in a clean centrifuge tube ; 3. ( Recommended ) Preparation of dead E.coli. If the dead E.coli is needed as a control, the dead E.coli can be obtained by heating the living E.coli in a water bath at 95 °C for 5 min, or at 58 °C for 3 h. the subsequent operation of the dead E. coli is the same as that of the living E. coli ; 4.Two copies of live E.coli, one without PMA treatment, and one with 25 µM PMA treatment ( the optimal PMA concentration for treating different types or different sources of bacteria needs to be consulted in the relevant literature ) ; 5.The PMA-treated samples were placed on a shaker at room temperature and incubated in the dark for 10 min to fully mix the dye with the sample ; 6.Exposure of the sample, you can use blue or white light source, irradiation time to explore their own. For example, a 60 W blue light can be used for 15 min. Note : 1 If a halogen lamp is used, we recommend that the PMA-treated sample tube be placed on an ice block 20 cm away from the light source. Ice should be placed in a transparent tray. Adjust the light source to point directly to the sample, photolysis for 5-15 min ; if the bacteria obtained from the environment are directly used for experiments, due to the complexity or turbidity of the environmental samples, the photolysis time needs to be prolonged appropriately. 7.Treated and untreated live E.coli 5000 × g, centrifuged for 10 min, remove the supernatant ; 8.Select the appropriate genomic DNA extraction kit according to the sample type, and use the same elution volume for each group of samples when elution DNA. Note : DNA extraction steps refer to the instructions of the kit used. Part of the mechanism of action of PMA is to remove PMA-bound DNA from the sample by precipitation ; therefore, when extracting genomic DNA, each group should use the same volume of genomic DNA eluent for volume normalization ( the amount of genomic DNA extracted from dead bacteria and live bacteria is inconsistent, so the concentration of the two is significantly different ). 9.Preparation of reaction mixture according to the following system : Note : 1 For the DNA extracted by commercial DNA extraction kit, the qPCR template was optimized with 2 µL as the initial volume ; 2 The template volume should not exceed 10 % of the final reaction volume ; 3 Template concentration : gDNA as template, usually 1-10 ng ; the final concentration of PCR primers is usually 0.4µM, which can get better results. When the reaction performance is poor, the primer concentration can be adjusted in the range of 0.2-1µM. 10.Slightly vortex the reaction mixture, transfer the fixed volume to the PCR tube. 11. Test procedure Note : 1 The extension time is adjusted according to the instrument ; the Taq enzyme in mix can be activated within 2 min, but the genomic DNA may require longer denaturation time, which can be increased at this time, and the specific denaturation time can be adjusted according to the sample type.12. ( Optional ) Data analysis Using live bacteria and dead bacteria as controls, the number of live cells in the sample was analyzed and calculated. It is recommended to verify the suitability of primers and PCR procedures before starting PMA qPCR detection of live bacteria. Calculation of dead and living bacteria control dCt ( 1 ) After the end of qPCR, the Ct value of each sample was calculated by instrument software ; ( 2 ) By calculating the dCt of each control bacteria, it was judged whether PMA successfully inhibited the amplification of dead bacterial DNA. The calculation is as follows : dCt live = Ct ( live, PMA treated ) -Ct ( live, PMA untreated ) dCt die = Ct ( die, PMA treated ) -Ct ( die, PMA untreated ) ( 3 ) The dCt expectation of living bacteria is close to 0 ± 1, which indicates that PMA does not affect the amplification of living cell DNA ;( 4 ) The expected value of dCt of dead bacteria is greater than 4 ( dCt is 4 means that it is reduced by about 16 times, that is, 94 % of dead bacterial DNA is removed ; a dCt of 8 indicated a decrease of about 250 times, that is, 99.6 % of the dead bacterial DNA was removed ).( 5 ) The dCt of dead bacteria depends on many factors, including : strain / cell type ; the way bacteria are killed ; the concentration of PMA used ; amplified sequence length. 13. Calculation of the proportion of viable ( optional ) bacteria If the control results of dead and live bacteria are normal, the proportion of live bacteria in the sample can be calculated.( 1 ) Calculate the dCt value of the sample : dCt sample = Ct ( sample, PMA treated ) -Ct ( sample, PMA untreated ) ( 2 ) Conversion of dCt value to live bacteria ratio : PMA inhibition multiple = 2 ( sample dCt ) Viable bacteria % = 100 / PMA inhibition multiple 14. ( Optional ) Calculate the absolute number of live bacteria If you want to calculate the absolute number of viable bacteria in the sample, you need to use a known number of target bacteria genomic DNA to make a standard curve. It is recommended that the diluted concentrations of several groups of genomes are within the range of the qPCR analysis system.( 1 ) qPCR was performed with the appropriate genome, and the Ct value was used as the ordinate, and the number of cells was used as the abscissa. The R2 value is calculated to determine the linearity, and the slope and y-axis intercept are displayed. ( 2 ) Calculate the copy number of the experimental samples : Ct = slope * cell number + y axis intercept ( y = mx + b ) Bacterial count sample = ( Ct-y axis intercept ) / slope Note : The live bacterial DNA was not lost during the purification process. Examples : Scope of application：Live bacteria detection... Read More | Product content: S665546Component50 TStorageS665546ABuffer QSL45 mLRTS665546BBuffer RIL11 mL2-8℃S665546CBuffer ML10 mLRTS665546DBuffer GW1 (concentrate)13 mLRTS665546EBuffer GW2 (concentrate)26 mLRTS665546FBuffer EBL13 mLRTS665546GRNase A240 µLRTS665546HLysis Tubes Ⅱ50 Product content: S665546Component50 TStorageS665546ABuffer QSL45 mLRTS665546BBuffer RIL11 mL2-8℃S665546CBuffer ML10 mLRTS665546DBuffer GW1 (concentrate)13 mLRTS665546EBuffer GW2 (concentrate)26 mLRTS665546FBuffer EBL13 mLRTS665546GRNase A240 µLRTS665546HLysis Tubes Ⅱ50 EARTS665546ISpin Columns DM With Collection Tubes50 EARTProduct IntroductionThis kit provides a method for extracting total DNA from soil or fecal samples, including the total DNA of cells, bacteria, parasites, and viruses in the samples. It is also suitable for extracting DNA from samples containing high concentrations of PCR reaction inhibitors. This reagent kit adopts a unique buffering system to efficiently bind DNA from the lysis solution to the adsorption column. Inhibitors of PCR and enzyme reactions, as well as residual impurities, can be effectively removed through washing steps. Finally, high-purity DNA can be obtained by washing with low salt buffer or water. The purified DNA can be directly used for downstream experiments such as second-generation sequencing (16S amplicons and metagenomes), library construction, PCR, qPCR, Southern Blot, enzyme digestion molecular markers, etc.Self prepared reagents1. Constant temperature mixer - Product number: CW25932. Anhydrous ethanol, isopropanol3. Vortex oscillator or tissue grinderPreparation and important precautions before the experiment1. Samples should avoid repeated freeze-thaw cycles, otherwise it may result in smaller extracted DNA fragments and a decrease in extraction volume.2.Before the first use, anhydrous ethanol should be added to Buffer GW1 (concentrate) and Buffer GW2 (concentrate) according to the instructions on the reagent bottle label.3. Take out the buffer RIL before use and store it at 2-8 ℃ immediately after use.Operation steps1. Centrifuge the Lysis Tube briefly to allow the beads to settle at the bottom.2. a. Add 0.1-0.3 g of soil or fecal sample to Lysis Tube, and add 740-820 µ L Buffer QSL and 4 µ L RNase A, tighten the tube cover and briefly vortex to mix.b. If fecal samples are stored in non lytic fecal preservation solutions (such as CWY041S and CWY041M), add 200 to Lysis Tube µ L-600 µ L solid-liquid mixture, centrifuge at 13000 rpm for 1 minute, discard the storage solution (if the amount of solid after centrifugation is too small, it can be enriched again, but should not exceed 0.3g). Join 620 µ LBuffer QSL and 4 µ L RNase A, tighten the tube cover and briefly vortex to mix.3. Fix the Lysis Tube in an oscillating grinding device equipped with a 2 mL adapter and process it according to the optimized grinding conditions of your equipment (see appendix).4. Shake the Lysis Tube on a constant temperature mixer at 70 ℃ and 1200 rpm for 10 minutes. Subsequently, centrifuge at 13000 rpm for 2 minutes to precipitate solid particles. Transfer 540 µ Transfer the supernatant to a new 2 mL centrifuge tube.5. Add 180 µ L Buffer RIL, vortex for 5 seconds, centrifuge at 13000 rpm for 2 minutes.Attention: Remove the buffer RIL before use and store it at 2-8 ℃ immediately after use.6. Add 160 to the new centrifuge tube in sequence µ L Buffer ML, 480 µ Supernatant from step 5, 320 µ L isopropanol, vortex for 5 seconds.7. Transfer the solution from the previous step to 650 µ Centrifuge at 12000 rpm (~13400 × g) for 1 minute into the spin columns DM that have been loaded into the collection tube.8. Discard the waste liquid in the collection pipe and place the adsorption column back into the collection pipe. Repeat step 7 until all the solution has been transferred.9. Add 500 to the adsorption column µ L Buffer GW1 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.10. Add 500 to the adsorption column µ L Buffer GW2 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube. 11. Repeat step 10.12.12000 rpm for 2 minutes and discard the waste liquid from the collection tube. Place the adsorption column at room temperature for a few minutes to thoroughly air dry.Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).13. Place the adsorption column in a new centrifuge tube (self provided) and add 50-200 drops of suspended droplets to the middle of the adsorption column µ L Buffer EBL or sterilized water, leave at room temperature for 2-5 minutes, centrifuge at 12000 rpm for 1 minute, collect DNA solution, and store DNA at -20 ℃.Note: 1) Incubating at room temperature for 5 minutes before centrifugation can increase yield.2) Use an additional 50-100 µ Further elution with L buffer or sterilized water can increase yield.3) If you want to increase the final concentration of DNA, you can add the DNA eluent obtained in step 13 back onto the adsorption membrane and repeat step 13, but it may reduce the total yield.4) The elution buffer does not contain chelating agents, please store DNA at -20 ℃.5) The residual trace PCR inhibitors in the genomic DNA template may have adverse effects on the PCR reaction, which can usually be resolved by diluting the DNA by 2-10 times.Appendix: Grind the sample using one of the following methods1. Manually vortex oscillate at maximum speed on the vortex oscillator for 10 minutes.2. On a vortex oscillator equipped with a 1.5-2 mL horizontal centrifuge tube holder, oscillate at maximum speed for 10 minutes (keeping the Lysis Tube horizontal). If the sample size exceeds 12, extend by 5-10 minutes. For example, using Scientific Industries or Mobile's Vortex Genie2 vortex oscillator.3.When using Qiagen's TissueLyser II, grind at 25Hz for 10 minutes.4.When using Qiagen's PowerLyzer 24 Homogenizer, homogenize at 2000 rpm for 30 seconds, pause for 30 seconds, and then homogenize again at 2000 rpm for 30 seconds.5.When using FastPrep-24 from MP Biomedicals, the recommended speed is 6.0 and the time is 40 seconds... Read More | The Succinic Acid (Succinate) assay kit is suitable for the specific assay of succinic acid in wine, cheese, eggs, sauce and other food products. Succinic acid (or succinate) is found in all plant and animal materials as a result of the central metabolic role played by this dicarboxylic acid in the The Succinic Acid (Succinate) assay kit is suitable for the specific assay of succinic acid in wine, cheese, eggs, sauce and other food products. Succinic acid (or succinate) is found in all plant and animal materials as a result of the central metabolic role played by this dicarboxylic acid in the Citric Acid Cycle. Succinic acid concentrations are monitored in the manufacture of numerous foodstuffs and beverages, including wine, soy sauce, soy bean flour, fruit juice and dairy products (e.g. cheese).Product Description： Succinic acid is found in all plant and animal materials as a result of the central metabolic role played by this dicarboxylic acid in the Citric Acid Cycle. Succinic acid concentrations are monitored in the manufacture of numerous foodstuffs and beverages, including wine, soy sauce, soy bean flour, fruit juice and dairy products (e.g. cheese). The ripening process of apples can be followed by monitoring the falling levels of succinic acid. The occurrence of > 5 mg/kg of this acid in egg and egg products is indicative of microbial contamination. Apart from use as a flavouring agent in the food and beverage industries, succinic acid finds many other non-food applications, such as in the production of dyes, drugs, perfumes, lacquers, photographic chemicals and coolants. Preparation Instructions：Suitable for succinate determination in food, beverage, agricultural products, and other biological samples.Note for Content：The number of manual tests per kit can be doubled if all volumes are halved. This can be readily accommodated using the MegaQuantTM Wave Spectrophotometer (D-MQWAVE).Browse all of our organic acid assay kits.Principle：The Succinate Assay Kit provides a simple, one step assay for measuring succinate. In this assay succinate is converted to pyruvate which reacts with specific reagents and dye to form a colored product. The color intensity at 570 nm or fluorescencAdvantages：Extended cofactors stability. Dissolved cofactors stable for > 1 year at 4oC.Very competitive price (cost per test)All reagents stable for > 2 years as suppliedVery rapid reaction (even at room temperature)Mega-Calc™ software tool is available from our website for hassle-free raw data processingStandard includedSuitable for manual, microplate and auto-analyser formats... Read More | Inquire |