| Description | Starch hydrolases include α-amylase (α-AL, EC 3.2.1.1) and β-amylase (β-AL). α-Amylase randomly catalyzes the hydrolysis of α-1,4-glycosidic bonds in starch, producing reducing sugars such as glucose, maltose, maltotriose, and dextrins, while simultaneously Starch hydrolases include α-amylase (α-AL, EC 3.2.1.1) and β-amylase (β-AL). α-Amylase randomly catalyzes the hydrolysis of α-1,4-glycosidic bonds in starch, producing reducing sugars such as glucose, maltose, maltotriose, and dextrins, while simultaneously reducing the viscosity of starch, hence it is also known as the liquefying enzyme. α-Amylase is widely distributed, from microorganisms to higher plants. Detection Principle: Starch hydrolases catalyze the hydrolysis of starch to produce reducing sugars. These reducing sugars reduce 3,5-dinitrosalicylic acid (DNS) to produce a brown-red-colored compound with an absorption peak at 540 nm. The amylase activity is calculated by measuring the rate of increase in absorbance at 540 nm. α-Amylase is heat-stable, but β-amylase can be inactivated by heating at 70°C for 15 minutes. Therefore, after the crude enzyme extract is treated at 70°C for 15 minutes, only α-amylase can catalyze starch hydrolysis. Detection Range: 0.0156 - 1 mg/mL Sensitivity: 0.0078 mg/mL Applicable Samples: Saliva, animal tissues, plant tissues (seeds or newly germinated seedlings) Note: The detection range and sensitivity are based on the standard. The actual detection range and sensitivity for activity need to be calculated according to the sample conditions.G1501772Component96TStorageG1501772ADNS Reagent40 mL2-8℃. Store in the dark.G1501772BSubstrate1EA2-8℃G1501772CStandard1EA2-8℃Note: Before formal testing, it is recommended to perform a preliminary test with 2-3 samples expected to have significant differences.User-Prepared Instruments and Reagents1.Microplate reader or visible spectrophotometer (capable of measuring absorbance at 540 nm)2.96-well plate or micro glass cuvettes, adjustable micropipettes and tips3.Centrifuge, water bath4.Deionized water5.Homogenizer (for tissue samples)Experimental Procedure1. Reagent PreparationReagent NameReagent PreparationNotesDNS ReagentReady-to-use; Equilibrate to room temperature before use.Store at 4°C protected from light.SubstrateBefore use, add 20 mL deionized water, invert and shake several times, heat until dissolved.Unused reagent can be stored at 4°C for one week. If precipitate forms, heat to 70°C to dissolve.StandardBefore use, add 1 mL deionized water to dissolve, obtaining a 10 mg/mL standard (Glucose) stock.Can be stored at 4°C for 2 weeks.2. Standard Curve SetupDilute the 10 mg/mL standard stock solution with deionized water to concentrations of 1, 0.5, 0.25, 0.125, 0.0625, 0.0313, and 0.0156 mg/mL as shown in the table below.TubeStandard VolumeDeionized Water Volume (µL)Standard Concentration (mg/mL)Std.140µL (10 mg/mL)3601Std.2200µL of Std.12000.5Std.3200µL of Std.22000.25Std.4200µL of Std.32000.125Std.5200µL of Std.42000.0625Std.6200µL of Std.52000.0313Std.7200µL of Std.62000.0156Note: The standard curve must be generated with each experiment. Diluted standard solutions are unstable and must be used within 4 hours3. Sample PreparationNote: Fresh samples are recommended.3.1 Animal TissueWeigh approximately 0.1 g of tissue. Add 1 mL of deionized water and homogenize. Transfer the homogenate to a centrifuge tube. Let it stand at room temperature for 15 minutes, vortexing every 5 minutes for sufficient extraction. Centrifuge at 6,000 g for 10 minutes at room temperature. Aspirate the supernatant and dilute to 10 mL with deionized water. Mix well. This is the amylase stock solution.3.2 Plant TissueWeigh approximately 0.1 g of tissue. Add 1 mL of deionized water and grind. Sonicate for 5 minutes (power 20%, pulse 3s on, 7s off, repeat 30 times). Let it stand at room temperature for 15 minutes, vortexing every 5 minutes for sufficient extraction. Centrifuge at 6,000 g for 10 minutes at room temperature. Aspirate the supernatant and dilute to 10 mL with deionized water. Mix well. This is the amylase stock solution.3.3 Saliva, and Other Liquid SamplesAssay directly. It is recommended to perform a preliminary test to determine the appropriate dilution factor.Note:For animal tissues with high fat content, remove the upper fat layer after centrifugation before collecting the supernatant.If protein concentration measurement is required, use Aladdin's BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648).4. Assay Steps4.1 Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 540 nm. For spectrophotometers, zero the instrument with deionized water.4.2 Preheat a water bath to 70°C.4.3 Take 75 µL of sample and incubate in a boiling water bath for 5 minutes. This will be used as the Control tube.4.4 Sample Measurement (Add reagents sequentially into microcentrifuge tubes as below):ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Control Tube (µL)Deionized Water75000Standard (various conc.)07500Sample007575 (boiled sample)Heat at 70°C for 15 min, then cool.Substrate00750Incubate in a constant temperature water bath at 40°C for 5 min.DNS Reagent150150150150Substrate75750754.5 Mix well. Incubate in a boiling water bath for 5 minutes. Cool. Transfer 200 µL to a 96-well plate or micro glass cuvette. Measure the absorbance at 540 nm. Calculate ΔA test = A test - A control ; ΔA standard = A standard - A blank. Note: Each sample requires a control tube. The blank tube only needs to be prepared once. It is recommended to perform a preliminary test with 2-3 samples expected to have significant differences before the formal experiment. If A test > 2, the enzyme activity is too high, and the sample must be diluted with deionized water to an appropriate concentration (multiply by the dilution factor in the calculation). If ΔA test < 0.005, re-extract the sample reducing the final volume of deionized water used for dilution.5. Calculation of Results 5.1 Standard Curve Plotting Plot the standard concentration (y-axis) against ΔA standard (x-axis) to generate the standard curve. Substitute ΔA test into the standard curve equation to calculate y (mg/mL). 5.2 α-Amylase Activity Calculation (1) Based on Sample Fresh Weight Calculation (1) Based on Sample Fresh Weight Calculation Unit Definition: One unit of enzyme activity is defined as the amount of enzyme that catalyzes the production of 1 mg of reducing sugar per minute per gram of tissue. Calculation Formula: α-Amylase Activity (U/g weight) = y × V sample ÷ (W × V sample ÷ V total ) ÷ T × n = 2 × y ÷ W × n (2) Based on Sample Protein Concentration (2) Based on Sample Protein Concentration Calculation Unit Definition: One unit of enzyme activity is defined as the amount of enzyme that produces 1 mg of reducing sugar per minute per milligram of tissue protein. Calculation Formula: α-Amylase Activity (U/mg prot) = y × V sample ÷ (Cpr × V sample ) ÷ T × n = 0.2 × y ÷ Cpr × n (3) Based on Liquid Sample Volume Calculation Unit Definition: One unit of enzyme activity is defined as the amount of enzyme that produces 1 mg of reducing sugar per minute per liter of liquid sample. Calculation Formula: α-Amylase Activity (U/L) = 1000 × y ÷ T × n = 200 × y × n Parameter Definitions: y: Concentration of reducing sugar calculated from the standard curve (mg/mL) V sample : Volume of sample added to the reaction system (0.075 mL) W: Sample weight (g) V total : Total volume of the sample extract (10 mL) T: Enzymatic reaction time (5 minutes) n: Sample dilution factor Cpr: Sample protein concentration (mg/mL) 1000: Conversion factor between liters and milliliters (1 L = 1000 mL)6. Representative ResultsTypical Standard Curve: y = 0.4948x - 0.0179, R² = 0.9982Precautions1. Biochemical reagents are generally irritating and potentially biologically toxic. For your safety and health, please use appropriate biosafety precautions throughout the experiment, including wearing lab coats, masks, gloves, and head covers. Perform experiments in a fume hood or biosafety cabinet.2. This product is for research use only. Not for use in clinical diagnosis... Read More | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | This reagent kit uses highly sensitive silver dye, which can be applied to protein staining of denatured and non denatured gels. It has the advantages of clear target bands, low background, and flexible control of operation time. In addition, this reagent kit has added a short-term sensitization This reagent kit uses highly sensitive silver dye, which can be applied to protein staining of denatured and non denatured gels. It has the advantages of clear target bands, low background, and flexible control of operation time. In addition, this reagent kit has added a short-term sensitization step, which can significantly reduce the background and enhance the brightness of the target band. P665901Component20 TStorageP665901ASilver Stain Sensitizer (500×)2×1 mLRTP665901BSilver Stain Enhancer3 mLRTP665901CSilver Stain2×250 mLRTP665901DSilver Stain Developer4×125 mLRT Matters needing attention1. Please prepare 50 ml of fixed solution (ultrapure water: ethanol: acetic acid=6:3:1), 50 ml of eluent (10% ethanol), and 50 ml of termination solution (5% acetic acid) in advance.2. Please use deionized water and clean glass or plastic containers during operation, and wear disposable gloves for operation.The entire silver dyeing process needs to be carried out on a shaker, with a rotation speed of about 60 rpm.4. Self prepared ethanol and glacial acetic acid are required.Instructions for useThe dosage of each solution in the following operation steps takes the gel with a size of 8.5 × 5.5 cm and a thickness of 1.0 mm as an example. The gel is immersed in the solution completely, and is operated on a shaker, with a general dosage of 25 ml. For large gel, the dosage of each solution should be scaled up according to the gel volume. Please prepare 50 ml of fixed solution (ultrapure water: ethanol: glacial acetic acid=6:3:1), 50 ml of eluent (10% ethanol), and 50 ml of termination solution (5% glacial acetic acid) in advance.1. Water washing: After electrophoresis is completed, wash the gel twice with ultrapure water for 5 minutes each time.2. Fixation: Fix the gel twice with 25 ml of fixative solution for 15 minutes each time.3. Elution: Wash the adhesive twice with eluent, each time for 5 minutes.4. Water washing: Wash the glue twice with ultrapure water, each time for 5 minutes.5. Sensitization: put the gel washed in the previous step into the silver dye sensitization working solution, incubate it accurately for 1 minute at room temperature, and then wash it with ultrapure water for three times, each time for 20 seconds. Preparation of silver staining sensitization working solution: Take 50 µ l Silver Stain Sensitivity (500 x) and add it to 25 ml of ultrapure water, mix well.6. Silver staining: discard ultrapure water and incubate gel in silver staining working solution for 30 minutes. Preparation of silver staining working solution: Take 25ml Silver Stain and add 50 µ l Silver Stain Enhanced to mix well.7. Water washing: Quickly wash the glue twice with ultrapure water, with each washing accurately controlled for 20 seconds.8. Development: Immerse the washed gel in the developer immediately and incubate it at room temperature for 2-3 minutes until the protein strip is clear. Preparation of developer: Take 25ml Silver Stain Developer and add 30 µ l Silver Stain Enhanced to mix well. Attention: Within 30 seconds of development, protein bands begin to appear and continue to develop for 2-3 minutes. If the protein band appears lighter, the development time can be appropriately extended to 5 minutes or more.9. Termination: After washing the developer on the gel with the termination solution, soak the gel in a new termination solution to react for 10 minutes.Experimental imagesSilver staining results of BSA protein samples after 10% SDS-PAGE gel electrophoresisThe molecular weight of BSA protein is about 66 kD, and the loading amounts from left to right are 50 ng, 10 ng, and 5 ng, respectively... Read More | Inquire | Product content: Component S665549 50 preps Buffer SW 60 ml Buffer SL 60 ml Buffer GL 50 ml Buffer GW1(concentrate) 2X13 ml Buffer GW2(concentrate) 15 ml Buffer GE 15 ml Spin Columns DM 50 with Collection Tubes 50Product IntroductionThis kit is suitable for Product content: Component S665549 50 preps Buffer SW 60 ml Buffer SL 60 ml Buffer GL 50 ml Buffer GW1(concentrate) 2X13 ml Buffer GW2(concentrate) 15 ml Buffer GE 15 ml Spin Columns DM 50 with Collection Tubes 50Product IntroductionThis kit is suitable for extracting total DNA from fecal samples, including the total DNA of cells, bacteria, parasites, and viruses in the samples, as well as samples containing high concentrations of PCR reaction inhibitors. This product can process up to 300 mg of fecal samples and purify to obtain mainly 20-30 kb DNA fragments. The purification process does not require toxic solvents such as phenol or chloroform, and does not require ethanol precipitation. High purity DNA can be obtained within one hour. This reagent kit adopts a unique buffering system to efficiently bind DNA from the lysis solution to the adsorption column. At the same time, protein impurities and other organic compounds that inhibit downstream reactions in feces can flow through the membrane. Inhibitors of PCR and enzyme reactions, as well as residual impurities, can be effectively removed through two 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 enzyme digestion, PCR, Real Time PCR, library construction, Southern Blot, and molecular labeling.Preparation 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 and GW2 according to the instructions on the reagent bottle label.3. Before use, please check whether there is crystallization or precipitation in Buffer SL and Buffer GL. If there is crystallization or precipitation, please dissolve Buffer SL and Buffer GL again in a 56 ℃ water bath.4. If downstream experiments are sensitive to RNA contamination, 4 can be added after adding Buffer SL µ RNase A of DNase Free (100 mg/ml) is not provided in this kit. If needed, it can be ordered separately from our company, item number: S665549Operation steps1. Take a fecal sample of 100-300 mg and place it in a centrifuge tube (provided by oneself).2. Add 1 ml of Buffer SW and vortex for 3-5 minutes to evenly disperse the sample in the solution. Centrifuge at 12000 rpm (~13400 × g) for 1 minute and discard the supernatant.3. Add 1 ml of Buffer SL and vortex for 3-5 minutes to evenly disperse the sample in the solution. Take a water bath at 65 ℃ for 20 minutes and vortex for 15 seconds every 5 minutes. Note: To remove RNA, add 4 after completing the above steps µ RNase A solution (product number: CW0601S) with a concentration of 100 mg/ml, shake well and let stand at room temperature for 5-10 minutes.4.Centrifuge at 2000 rpm for 3 minutes and transfer the supernatant to a new centrifuge tube (provided by oneself).5. Add an equal volume of Buffer GL to the supernatant, invert and mix 15-25 times, and leave on ice for 5 minutes. Centrifuge at 12000 rpm for 5 minutes. Attention: At this time, the liquid may be in a transparent or turbid state, which does not affect the experiment. 6. Add the supernatant obtained in step 5 to the spin columns DM that have been loaded into the collection tube. If the solution cannot be added at once, it can be transferred multiple times. Centrifuge at 12000 rpm (~13400 × g) for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.7. Add 500 to the adsorption column µ 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. 8. Repeat step 7.9. Add 500 to the adsorption column µ 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.10.12000 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.).11. Place the adsorption column in a new centrifuge tube (self provided) and add 50-100 drops of suspended droplets to the middle of the adsorption column µ L Buffer GE 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) If downstream experiments are sensitive to pH or EDTA, they can be washed off with sterilized water. The pH value of the eluent has a significant impact on the elution efficiency. If water is used as the eluent, its pH value should be ensured to be between 7.0-8.5 (NaOH can be used to adjust the pH value of the water to this range). When the pH value is below 7.0, the elution efficiency will be reduced2) Incubating at room temperature for 5 minutes before centrifugation can increase yield.3) Use an additional 50-100 µ Further washing with buffer GE or sterilized water can increase yield.4) If you want to increase the final concentration of DNA, you can add the DNA eluent obtained in step 11 back onto the adsorption membrane and repeat step 11; It is possible to increase the final concentration of DNA, but it may reduce the total yield. If the amount of DNA is less than 1 µ g. Recommended 50 µ Wash with buffer GE or sterilized water.5) DNA stored in water can be affected by acidic hydrolysis. If long-term storage is required, it is recommended to elute with Buffer GE and store at -20 ℃.6) The residual trace PCR inhibitors in the genomic DNA template may have adverse effects on the PCR reaction, which can be solved by diluting DNA by 2-10 times... Read More |