| 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 | Inquire | DescriptionPhoto KitAlysis Starter Kit enables screening of 24 micro-scale simultaneous photocatalytic reactions with consistent and reproducible photon intensity. User guide is provided in the below hyperlink.Photo KitAlysis Operating InstructionsComponents:Photo KitAlysis LED ControllerBlue LED DescriptionPhoto KitAlysis Starter Kit enables screening of 24 micro-scale simultaneous photocatalytic reactions with consistent and reproducible photon intensity. User guide is provided in the below hyperlink.Photo KitAlysis Operating InstructionsComponents:Photo KitAlysis LED ControllerBlue LED Array (470 nm)Photo KitAlysis Reaction BlockTorque screwdriverSmall screwdriver to easily remove torqued screws after reaction is completeFeatures:Designed and tested by synthetic chemists.Controller provides repeatable milliamp selection for photon intensity0-30 mA variable LED output3 different LED options: blue (470 nm, included), green (527 nm, sold separately), and white (sold separately)Non-magnetic LED baseChemically resistant LED coverPTFE coated cablingDesigned to be used withPhoto KitAlysis High-Throughput Reaction Screening Kit(sold separately).Best when used withKitAlysis Benchtop Inertion Box(sold separately)... Read More | Product Content R669990Component50 TStorageR669990ADNase I1000 U-20℃. Avoid freeze/thaw cycle.R669990B10×Reaction Buffer1 mL-20℃. Avoid freeze/thaw cycle.R669990CBuffer RL35 mLRTR669990DBuffer RW135 mLRTR669990EBuffer RW2 (concentrate)11 mLRTR669990FRNase-Free Water10 Product Content R669990Component50 TStorageR669990ADNase I1000 U-20℃. Avoid freeze/thaw cycle.R669990B10×Reaction Buffer1 mL-20℃. Avoid freeze/thaw cycle.R669990CBuffer RL35 mLRTR669990DBuffer RW135 mLRTR669990EBuffer RW2 (concentrate)11 mLRTR669990FRNase-Free Water10 mLRTR669990GSpin Columns RM with Collection Tubes50 setsRTR669990HRNase-Free Centrifuge Tubes (1.5 mL)50 EART ProductsThis kit combines highly efficient guanidine isothiocyanate cleavage technology with silica matrix membrane purification for the efficient extraction of total RNA from animal cells and tissues, typically up to 30 mg of tissue or 1x107 cells as a starting sample. The kit also allows recovery of incompletely purified RNA, in vitro transcription and RNA from enzymatic reactions. high quality RNA with molecular weights greater than 200 bases can be extracted and purified using the kit with virtually no DNA residue. If RNA experiments that are very sensitive to trace DNA are to be performed, residual DNA can be removed by on-column digestion using RNase-free DNase. The extracted RNA can be used in downstream experiments such as RT-PCR, Nothern Blot and Dot Blot. Self-contained reagents: β-mercaptoethanol, anhydrous ethanol (freshly opened or for RNA extraction).Pre-experiment Preparation and Important Notes1. To prevent RNase contamination, attention should be paid to the following aspects:1) Use RNase-free plastics and tips to avoid cross-contamination.2) RNase-free water should be used to prepare the solution.(3) Operators wear disposable masks and gloves, and change gloves diligently during the experiment.2. Avoid repeated freezing and thawing of the extracted samples, otherwise it will affect the amount and quality of RNA extraction.3. Please add β-mercaptoethanol to Buffer RL before use, add 10µl of β-mercaptoethanol to 1ml of Buffer RL. Buffer RL with β-mercaptoethanol can be stored for 1 month at room temperature.4. Anhydrous ethanol should be added to Buffer RW2 before first use according to the instructions on the reagent bottle label.5. Buffer RL may be heated at 56°C to dissolve if precipitation occurs and then left at room temperature.All centrifugation steps are performed at room temperature and all maneuvers are performed quickly.Procedure1. Sample handling1a Tissue: Grind tissue in liquid nitrogen. Add 600 µl Buffer RL for every 20-30 mg of tissue (check for addition of β-mercaptoethanol before use), and 350 µl Buffer RL for tissue samples of less than 20 mg. Sample volume is not to exceed one-tenth of the Buffer RL volume.1b Cells in monolayer culture: Lysed or processed into cell suspension directly in culture flask, centrifuged to obtain cell precipitate, discarded the supernatant, added 600µl Buffer RL for every 6-10 cm2 of culture area, 350µl Buffer RL for less than 6cm2, and blown several times repeatedly to make the cells lysed sufficiently.1c Cell suspension: centrifuge at 12,000 rpm (~13,400 × g) for 1 min and discard the supernatant to obtain the cell precipitate. Add 600 µl Buffer RL for every 5×106-1×107 cells, and 350 µl Buffer RL for less than 5×106 cells, and blow several times repeatedly to fully lysate.Note: 1) Try to get rid of the cell culture medium, which may inhibit cell lysis affecting RNA yield.2) Try to keep the cells well suspended and well lysed, otherwise RNA yield is affected.2. After the sample is fully lysed, leave it at room temperature for 5 minutes to allow complete separation of the protein-nucleic acid complex.3. Centrifuge at 12,000 rpm for 2-5 min and remove the supernatant for the following operations.4. Add 1x volume (600µl or 350µl) of 70% ethanol (prepared without RNase water) to the solution obtained in step 3 and mix well.Note: The addition of ethanol may produce a precipitate that will not affect subsequent experiments.5. Add all of the solution obtained in the previous step to the Spin Columns RM in the collection tube. If you cannot add all of the solution to the column at once, transfer it in two passes, centrifuge at 12,000 rpm for 1 minute, and discard the waste solution. Place the column back into the collection tube.Note: The maximum loading capacity of the adsorption column is 100µg, do not overload as this will affect the yield and purity of the RNA.6. Add 350 µl Buffer RW1 to the adsorbent column, centrifuge at 12,000 rpm for 1 min, discard the waste liquid and put the adsorbent column back into the collection tube.7. Preparation of DNase I mixture: Take 52 µl of RNase-Free Water, add 8 µl of 10×Reaction Buffer and 20 µl of DNase I (1 U/µl) to it, mix well, and prepare a final volume of 80 µl of reaction solution.8. Add 80µl of DNase I mixture directly to the adsorption column and incubate at 20-30°C for 15 minutes.9. Add 200 µl Buffer RW1 to the adsorbent column, centrifuge at 12,000 rpm for 1 min, discard the waste liquid and put the adsorbent column back into the collection tube.10. Add 500µl Buffer RW2 to the column (check that anhydrous ethanol is added before use), centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube, and put the column back into the collection tube.11. Repeat step 10.12. Centrifuge at 12,000 rpm for 2 minutes and pour off the waste liquid in the collection tube. Leave the adsorption column at room temperature for a few minutes to thoroughly dry the anhydrous ethanol in the adsorption column.Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can interfere with subsequent enzymatic reactions (digestion, PCR, etc.).13. Transfer the adsorbent column into a new centrifuge tube, add 30-50 µl of RNase-Free Water to the middle of the adsorbent membrane, leave it at room temperature for 1 min, centrifuge at 12,000 rpm for 1 min, collect the RNA solution, and store the RNA at -70°C to prevent degradation.Note: 1) The volume of RNase-Free Wate should not be less than 30 µl, too small volume affects the recovery rate.2) If you want to increase the RNA yield, repeat step 13 with 30-50 µl of fresh RNase-Free Water.3) If the RNA concentration is to be increased, the resulting solution can be reintroduced into the adsorption column and step 13 repeated... Read More |