| Description | Polyphenol Oxidase (PPO, EC1.10.3.1) is widely found in the plastids of plants, fungi, and insects. It is a copper-containing oxidase that can oxidize monophenols and diphenols to produce quinones, leading to browning. It is closely related to fruit and vegetable processing, tea quality, and Polyphenol Oxidase (PPO, EC1.10.3.1) is widely found in the plastids of plants, fungi, and insects. It is a copper-containing oxidase that can oxidize monophenols and diphenols to produce quinones, leading to browning. It is closely related to fruit and vegetable processing, tea quality, and tissue culture. The Plant Polyphenol Oxidase (PPO) Activity Assay Kit (Catechol, Micro method) provides a simple method to detect the activity level of polyphenol oxidase (PPO) in plant tissue samples.Detection Principle: Polyphenol oxidase (PPO) in the sample catalyzes the oxidation of catechol to produce quinones, which have a characteristic absorption peak at 410 nm. The rate of increase in absorbance at 410 nm is measured to calculate PPO activity.P1501774Component48T96TStorageP1501774AExtraction Buffer60 mL120 mL2-8℃P1501774BReagentⅠ24 mL48 mL2-8℃P1501774CReagentⅡ6 mL12 mL2-8℃. Store in the dark.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 ReagentsMicroplate reader or visible spectrophotometer (capable of measuring absorbance at 410 nm)96-well plate or micro glass cuvettes, adjustable micropipettes and tipsRefrigerated centrifuge, ice maker, constant temperature water bathDeionized waterHomogenizerExperimental Procedure1. Reagent PreparationReagent NameReagent PreparationNotesExtraction BufferReady-to-use; Equilibrate to room temperature before use.Store at 4°C.ReagentⅠReady-to-use; Equilibrate to room temperature before use.Store at 4°C.ReagentⅡReady-to-use; Equilibrate to room temperature before use.Store at 4°C protected from light; Toxic, handle with care.2. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for one month.2.1 Preparation of Crude Enzyme ExtractHomogenize the plant sample in ice-cold Extraction Buffer with a mass (g) to volume (mL) ratio of 1:5 to 1:10 (recommended: 0.1 g tissue + 1 mL Extraction Buffer). Centrifuge the homogenate at 8,000 g, 4°C for 10 minutes. Collect the supernatant and keep it on ice for assay.2.2 Boiled Sample ControlTake an appropriate amount of the crude enzyme extract and heat it in a boiling water bath for 5 minutes (seal to prevent moisture loss). Cool to room temperature.3. Assay Steps3.1 Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 410 nm. For spectrophotometers, zero the instrument with deionized water.3.2 Sample Measurement (Add reagents sequentially into 1.5 mL microcentrifuge tubes):ReagentControl Tube (µL)Test Tube (µL)Boiled Sample500Sample (supernatant)050ReagentⅠ200200ReagentⅡ50503.3 Mix thoroughly. Incubate in a 25°C water bath for 10 minutes, then immediately transfer to a boiling water bath for 10 minutes. After mixing, centrifuge at 5,000 g, 25°C for 10 minutes. Collect the supernatant. Transfer 200 µL of the supernatant to a micro glass cuvette or 96-well plate. Measure the absorbance of both the Test tube and Control tube at 410 nm. Calculate ΔA = Atest - Acontrol.Note:Each test tube requires a corresponding control tube.It is recommended to perform a preliminary test with 2-3 samples expected to have significant differences before the formal experiment.The optimal reaction temperature for PPO may vary slightly among different samples and can be adjusted between 25-37°C.If the sample absorbance is less than 0.02, consider increasing the sample volume appropriately. If the sample absorbance is greater than 1, it is advisable to dilute the sample before assay.4. Calculation of ResultsNote: We provide both the derived formula and a simplified formula. They are equivalent. It is recommended to use the simplified formula in bold for final calculation.4.1 Calculation Formula when using a 96-well plate:Unit Definition: One unit of enzyme activity is defined as the amount that causes a change of 0.005 in absorbance at 410 nm per minute per gram of tissue per mL of reaction mixture.PPO Activity (U/g fresh weight) = ΔA × Vtotal reaction÷ (W × Vsample / Vtotal sample ) ÷ 0.005 ÷ T = 120 × ΔA / W4.2 Calculation Formula when using a micro glass cuvette:Unit Definition: One unit of enzyme activity is defined as the amount that causes a change of 0.01 in absorbance at 410 nm per minute per gram of tissue per mL of reaction mixture.PPO Activity (U/g fresh weight) = ΔA × Vtotal reaction ÷ (W × V sample / Vtotal sample ) ÷ 0.01 ÷ T = 60 × ΔA / WParameter Definitions:Vtotal reaction: Total volume of the reaction system (0.3 mL)Vsample : Volume of sample added to the reaction (0.05 mL)Vtotal sample : Volume of Extraction Buffer added during homogenization (1 mL)T: Reaction time (10 minutes)W: Sample weight (g)PrecautionsThis product is for research use only. Not for use in clinical diagnosis. For your safety and health, please wear lab coats and disposable gloves during operation... Read More | Products contentN665978Component384 TStorageN665978AIndex N502-N522 Primers for Illumina 16×24 µL-20℃. Avoid freeze/thaw cycle.N665978BIndex N701-N729 Primers for Illumina24×16 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion to the Products contentN665978Component384 TStorageN665978AIndex N502-N522 Primers for Illumina 16×24 µL-20℃. Avoid freeze/thaw cycle.N665978BIndex N701-N729 Primers for Illumina24×16 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion to the transposase-based rapid DNA library construction kit, designed for Illumina platform library construction. It contains 16 N5 primers and 24 N7 primers, which can be used to prepare 384 different bipartite Index libraries. All reagents provided in the kit have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction. The libraries can be used for sequencing on Illumina platforms such as HiSeq X-10/4000/2500/2000 and MiSeq.Provide your own instruments, reagents and consumables1. Magnetic frame: DynaMagTM-2 is recommended.2. DNA purification and recovery kit: It is recommended to use Kangwei DNA purification and recovery kit by magnetic bead method.3. DNA building kit: It is recommended to use the Kangwei Century transposase method second-generation sequencing rapid DNA building kit.4. Anhydrous ethanol.5. Reaction tubes: It is recommended to use low adsorption PCR tubes with 1.5 ml centrifuge tubes; Tip: It is recommended to use a high quality filter tip to prevent contamination of kits and library samples. Pre-experiment Preparation and Important NotesPlease centrifuge briefly before opening the cap so that the liquid collects at the bottom of the tube to avoid cross-contamination between different primers.procedure For the use of the CombiVision Second Generation Sequencing Multisample Primer Kit, please follow the CombiVision Second Generation Sequencing Rapid DNA Library Kit protocol. Index N502-N522 Primers for Illumina Index N701-N729 Primers for Illumina... Read More | Products contentN669983Component240 TStorageN669983AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/thaw cycle.N669983BIndex N973-N996 Primers for Illumina24×10 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion kit to the transposase-Products contentN669983Component240 TStorageN669983AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/thaw cycle.N669983BIndex N973-N996 Primers for Illumina24×10 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion kit to the transposase-based Rapid DNA Library Construction Kit for Illumina platform library construction. Each kit contains one N5 primer and 24 N7 primers, which can be used to prepare 24 different single-ended Index libraries. All reagents provided in the kits have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction. The libraries can be used for sequencing on Illumina platforms such as HiSeq X-10/4000/2500/2000 and MiSeq. Provide your own instruments, reagents and consumables1. Magnetic frame: DynaMagTM-2 is recommended.2. DNA purification and recovery kit: It is recommended to use DNA purification and recovery kit by magnetic bead method.3. DNA building kit: It is recommended to use the Century transposase method second-generation sequencing rapid DNA building kit.4. Anhydrous ethanol.5. Reaction tubes: It is recommended to use low adsorption PCR tubes with 1.5 ml centrifuge tubes;Tip: It is recommended to use a high quality filter tip to prevent contamination of kits and library samples. Pre-experiment Preparation and Important NotesPlease centrifuge briefly before opening the cap so that the liquid collects at the bottom of the tube to avoid cross-contamination between different primers. ProcedureFor the use of the CombiVision Second Generation Sequencing Multisample Primer Kit, please follow the CombiVision Second Generation Sequencing Rapid DNA Library Kit protocol.Index N501 Primer for IlluminaIndex N901-N996 Primer for Illumina... Read More | Product content Q665687Component100 TStorageQ665687AQuick T4 DNA Ligase (15 U/µL)100 µL-20℃. Avoid freeze/thaw cycle.Q665687B2×Quick Ligation Reaction Buffer5×200 µL-20℃. Avoid freeze/thaw cycle. Product IntroductionThe Quick Ligation Reaction Kit allows ligationProduct content Q665687Component100 TStorageQ665687AQuick T4 DNA Ligase (15 U/µL)100 µL-20℃. Avoid freeze/thaw cycle.Q665687B2×Quick Ligation Reaction Buffer5×200 µL-20℃. Avoid freeze/thaw cycle. Product IntroductionThe Quick Ligation Reaction Kit allows ligation of DNA sticky or flush ends in 5 minutes at room temperature (25°C). The kit contains Quick T4 DNA Ligase and 2×Quick Ligation Reaction Buffer optimized for fast and efficient DNA ligation.The ligation efficiency of Quick Ligation is equivalent to 1 hour of conventional ligation with T4 DNA Ligase. The Quick Ligation products can be used directly in routine bacterial transformation experiments.matters needing attention1. This kit enables most of the linkage reactions to reach the reaction endpoint within 5 minutes or less at 25°C. Increasing the reaction time will not enhance the reaction efficiency. If you use the rapid connection reaction after 1 hour, the conversion efficiency will be significantly reduced; if the rapid connection reaction at 25 ℃ overnight, the conversion efficiency will drop to 75%.2. 2×Quick Ligation Reaction Buffer contains ATP, which should be thawed on ice and mixed thoroughly before use. It is recommended to freeze the buffer in small tubes for the first time, so as to avoid repeated freezing and thawing, which will affect the efficiency of DNA ligation.3. Since T4 DNA Ligase contains glycerol, which is sticky and easy to hang on the wall, it is recommended to collect the liquid to the bottom of the tube by centrifugation for a short period of time before use, and the tip of the lance should not go too deep into the liquid surface when taking samples to avoid sticking to the tip of the lance and causing losses.4. If the quick ligation product is used for electrotransformation, the PEG in the quick ligation reaction system will affect the efficiency of electrotransformation, and it is recommended to use a centrifugal column to purify the ligation product from DNA before electrotransformation.Usage1. The reaction solution was prepared according to the following system:*The amount of Insert DNA used: the molar ratio of Vector DNA and Insert DNA is generally 1:3-1:8, and the appropriate molar ratio of Vector DNA and Insert DNA can be selected according to the experimental situation.Calculation of DNA molar number: DNA molar number (nmol)=DNA mass (ng)/( 660daltons x number of inserted DNA bases bp).2. mix gently and centrifuge briefly. react at 25°C for 5 minutes.Note: The reaction time should not exceed 15 minutes, otherwise the connection efficiency will be reduced.3. Do not perform heat inactivation reactions. Centrifuge instantly and collect the solution from the wall to the bottom of the tube.Note: Heat inactivation significantly reduces transformation efficiency due to the presence of PEG in the buffer.4. After the reaction, store the DNA ligation product at 0-4℃, and then carry out transformation experiments; you can also store the DNA ligation product at -20℃.Note: When transforming by chemical method, do not add more than 10% of the volume of the receptor cell for the ligation product.5. Heat shock the ligation product to transform 50 µl of receptor cells or take 1-2 µl of ligation product to electroshock transform 50 µl of receptor cells.Note: 1) When transforming by chemical method, do not add more than 10% of the volume of the receptor cell for the ligation product.(2) If the quick ligation product is used for electrotransformation, it is recommended to use a centrifugal column to purify the ligation product from DNA before electrotransformation because the PEG in the quick ligation reaction system will affect the efficiency of electrotransformation... Read More | Products R669890Component50 TStorageR669890ADNase I1000 U-20℃. Avoid freeze/thaw cycle.R669890B10×Reaction Buffer1mL-20℃. Avoid freeze/thaw cycle.R669890CBuffer RL35 mLRTR669890DBuffer RW140 mLRTR669890EBuffer RW2 (concentrate)11 mLRTR669890FRNase-Free Water10 mLRTR669890GSpin Products R669890Component50 TStorageR669890ADNase I1000 U-20℃. Avoid freeze/thaw cycle.R669890B10×Reaction Buffer1mL-20℃. Avoid freeze/thaw cycle.R669890CBuffer RL35 mLRTR669890DBuffer RW140 mLRTR669890EBuffer RW2 (concentrate)11 mLRTR669890FRNase-Free Water10 mLRTR669890GSpin Columns FL with Collection Tubes50 setsRTR669890HSpin Columns RM with Collection Tubes50 setsRTR669890IRNase-Free Centrifuge Tubes (1.5 mL)100 EART ProductsThis kit adopts centrifugal adsorption columns with high efficiency and specificbinding of nucleic acids and unique buffer system, which can rapidly extract totalRNA from bacteria or cultured animal cells.The reaction can be completed in 30-40minutes, and the extracted total RNA is extremely pure and free of protein and othercontaminants, which is suitable for RT-PCR, Real-Time RT-PCR, microarray analysis,in vitro translation and other experiments. Self-contained reagents: Lysozyme, β-mercaptoethanol, anhydrous ethanol (freshlyopened or for RNA extraction). Pre-experiment Preparation and Important Notes 1. 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 duringthe experiment. 2. Add β-mercaptoethanol to Buffer RL before use to reach a final concentrationof 1%, e.g., add 10 µl of β-mercaptoethanol to 1 ml of Buffer RL. Buffer RL withβ-mercaptoethanol can be stored at 4℃ for 1 month, if precipitation occurs, pleaseheat to dissolve and use.3. Anhydrous ethanol should be added to Buffer RW2 before first use according tothe instructions on the reagent bottle label. 4. All centrifugation steps are carried out at room temperature if not otherwisespecified, and all steps should be performed quickly. Procedure 1. Centrifuge at 12,000 rpm (~13,400 x g) at 4°C for 2 minutes to collect theorganisms (maximum volume of organisms should not exceed 1 x 109) and carefullyremove all supernatants. Note: Supernatants that leave residues can interfere with the subsequent digestionprocess. 2. Thoroughly resuspend the organisms with 100 µl of TE buffer containing Lysozymeand incubate at room temperature. The specific formulation and incubation time areas follows:/The final concentration of Lysozyme in TE bufferincubation timeG-germ400µg/ml3-5minG+germ3mg/ml5-10min 3. Add 350 µl of Buffer RL (check that β-mercaptoethanol has been added beforeuse), vortex and shake to mix (insoluble precipitate may appear in this step), addall of the solution and the precipitate to the filter columns (Spin Columns FL) thathave been loaded into the collection tubes, and centrifuge at 12,000 rpm for 2minutes. 4. Add 250 µl of anhydrous ethanol to the filtrate obtained in the previous stepand mix well (a precipitate may appear at this point). Transfer the resulting solution together with the precipitate to a Spin Columns RM packed in a collectiontube, centrifuge at 12,000 rpm for 1 min, discard the waste solution and put thecolumn back into the collection tube.5. Add 350 µl Buffer RW1 to the adsorbent column, centrifuge at 12,000 rpm for1min, discard the waste liquid and put the adsorbent column back into the collectiontube.6. Preparation of DNase I mixture: Take 52µl of RNase-Free Water, add 8µl of 10×Reaction Buffer and 20µl of DNase I (1U/µl) to it, mix well, and make a finalvolume of 80µl of reaction solution.7. Add 80µl of DNase I mixture directly to the adsorption column and incubate at20-30°C for 15 minutes.8. Add 350 µl Buffer RW1 to the adsorbent column, centrifuge at 12,000 rpm for1min, discard the waste liquid and put the adsorbent column back into the collectiontube.9. Add 500 µl of Buffer RW2 to the column (check that anhydrous ethanol is addedbefore use), centrifuge at 12,000 rpm for 1 min, and discard the waste solution.10. Repeat step 9.11. Place the adsorbent column back into the collection tube and centrifuge at 12,000rpm for 2 minutes. Note: The purpose of this step is to remove residual ethanol from the adsorptioncolumn; ethanol residue can interfere with subsequent enzymatic reactions (zymography, PCR, etc.).12. Load the adsorption column into a new RNase-Free collection tube, add 30-50 µl of RNase-Free Water to the middle of the adsorption membrane, leave it at roomtemperature for 1 minute, centrifuge at 12,000 rpm for 1 minute, collect the RNAsolution, and store the RNA at -70°C to prevent degradation. Note: 1) The volume of RNase-Free Water should not be less than 30 µl, too smallvolume affects the recovery rate. 2) If you want to increase the RNA yield, repeat step 12 with 30-50 µl of freshRNase-Free Water. If the RNA concentration is to be increased, the resulting solution can be reintroduced into the adsorption column and step 12 repeated... Read More |