| 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 | Inquire | Product contentG665801Component100 TStorageG665801A2×GoldStar Probe One Step Buffer1.4 mL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801BGoldStar Probe One Step EnzymeMix100 µL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801C50×High ROX50 µL-20&#Product contentG665801Component100 TStorageG665801A2×GoldStar Probe One Step Buffer1.4 mL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801BGoldStar Probe One Step EnzymeMix100 µL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801C50×High ROX50 µL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801DRNase-Free Water1.5 mL-20℃. Avoid freeze/ Thaw cycle. Product Introduction This product is a specialized kit for one-step Real-Time RT-qPCR using the probe method (TaqMan, Molecular Beacon, etc.). When using this product for Real Time RT-qPCR reaction, reverse transcription and quantitative PCR are carried out in the same reaction system, and there is no need to add reagents or open the cap of the tube during the reaction process, which avoids contamination and improves the experimental efficiency at the same time. With high detection sensitivity, strong fluorescence signal and high signal-to-noise ratio, this product is very suitable for the detection of RNA viruses and other trace RNA. The special buffer system contained in this product can maximize the effectiveness of reverse transcriptase and DNA polymerase at the same time and improve the efficiency of the reaction. A wider linear range can be obtained with this product, more accurate quantification of the target gene, good reproducibility and high confidence.ROX dye is used to correct the fluorescence signal error generated between wells of a quantitative PCR instrument, and is generally used in Real Time PCR amplifiers from ABI, Stratagene, and other companies. The excitation optics vary from instrument to instrument, so the concentration of ROX dye must be matched to the corresponding fluorescence quantitative PCR instrument. Instruments that do not require ROX calibration (G665836) Roche LightCycler 480, Roche LightCyler 96, Bio-rad iCyler iQ, iQ5, CFX96 and others. Instruments that require High ROX calibration (G665801) ABI Prism 7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, and others.matters needing attention1.Before using the reagents in this kit, please mix them gently by turning them up and down to avoid foaming as much as possible, and use them after brief centrifugation.2.This product uses RNA as the template for one-step RT-PCR experiment, RNase contamination should be avoided during operation, it is recommended to operate RNA in a special area, use special instruments and consumables, the operator with a mask and disposable gloves and often change the gloves, the experiment-related consumables should be processed with 0.1% DEPC (diethyl ether pyrocarbonate) aqueous solution for 12 hours at 37℃, and autoclaved for 30 minutes before use. The consumables should be treated with 0.1% DEPC (diethylpyrocarbonate) aqueous solution at 37℃ for 12 hours and autoclaved for 30 minutes.3.Repeated freezing and thawing of each reagent in this kit should be avoided as much as possible; repeated freezing and thawing may degrade the product performance.4.This kit must use specific primers, the choice of primers can be selected according to specific experiments, the good or bad primer design directly affects the results of RT-qPCR reaction, the design of primers need to consider the GC content, primer length, primer position, the secondary structure of the PCR product and other factors, it is recommended to use a professional primer design software for design.5.This kit is recommended to use specific probes, and it is recommended to use professional design software for designing.UsageThe following examples are conventional reaction systems and conditions, which should be improved and optimized according to the different templates, primer structures and target fragment sizes in actual operation. (Please prepare the reaction solution on ice.)1. Dissolve RNA template, primers, 2× GoldStar Probe One Step Buffer, GoldStar Probe One Step EnzymeMix and RNase-Free Water and set aside on ice.2. PCR reaction system:reagents25µl reaction systemfinal concentration2×GoldStar Probe One Step Buffer12.5µl1×Forward Primer, 10µM0.5µl0.2µM¹⁾Reverse Primer, 10µM0.5µl0.2µM¹⁾Probe, 10µM0.5µl0.2µM²⁾GoldStar Probe One Step EnzymeMix1.0µl RNA TemplateXµl10pg-100ng³⁾50 x Low ROX or High ROX (optional)⁴⁾0.5µl1×RNase-Free WaterUp to 25µlNote: 1) Usually, better results can be obtained with a primer concentration of 0.2 µM, and 0.1-1.0 µM can be used as a reference for setting the range.(2) The concentration of the probe used is related to the fluorescence quantitative PCR instrument used, the type of probe, and the type of fluorescent labeling substance, please refer to the instrument manual or the specific requirements for the use of each fluorescent probe for the adjustment of the concentration in actual use.(3) Usually the amount of RNA template is 10pg-100ng as a reference. Since the templates of different species contain different copy numbers of target genes, the templates can be diluted in gradient to determine the optimal amount of template to use.(4) The excitation optical system varies from instrument to instrument, choose to add 50×Low ROX or 50×High ROX according to the instrument using fluorescence quantification.3. Mix well, centrifuge briefly, and collect the solution at the bottom of the tube.4.RT-PCR reaction conditions:Note: 1) The hot start enzyme used in this product must be activated under the condition of pre-denaturation 95℃, 5-10min. 2) It is recommended to use the two-step PCR reaction program, if you can not get good experimental results due to the use of primers with lower Tm value, etc., you can try to carry out the three-step PCR amplification, and the annealing temperature should be set in the range of 56℃-64℃ as a reference... 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 | Products content S666097Component200 TStorageS666097A5×SuperFast One Step RT-qPCR U+ Buffer1 mL-20℃. Avoid freeze/thaw cycle.S666097BSuperFast One Step U+ Enzyme200 µL-20℃. Avoid freeze/thaw cycle.S666097CRNase-Free Water2×1.5 mL-20℃. Avoid freeze/thaw cycle. Products content S666097Component200 TStorageS666097A5×SuperFast One Step RT-qPCR U+ Buffer1 mL-20℃. Avoid freeze/thaw cycle.S666097BSuperFast One Step U+ Enzyme200 µL-20℃. Avoid freeze/thaw cycle.S666097CRNase-Free Water2×1.5 mL-20℃. Avoid freeze/thaw cycle. Products IntroductionThe SuperFast Probe One Step RT-qPCR U+ Kit is designed for quantitative PCR assays using RNA as a template (e.g., RNA viruses). Using gene-specific primers (GSP), reverse transcription and qPCR reactions are completed in a single tube, eliminating the need for additional tube-opening/pipetting operations, greatly increasing throughput and reducing the risk of contamination. The dUTP/UNG anti-contamination system is introduced in this kit. The heat-sensitive UNG rapidly degrades U-containing contaminants at room temperature; it is rapidly inactivated by reverse transcription at 55°C, without affecting the efficiency and sensitivity of qRT-PCR. Combined with optimized buffer systems and antibody-modified Taq enzymes and mutated M-MLV, the SuperFast Probe One Step RT-qPCR U+ Kit provides sensitivity up to 0.1 pg of total RNA or <10 copies of RNA template and enhanced thermal stability. 5× SuperFast One Step RT-qPCR U+ Buffer contains the following components The 5× SuperFast One Step RT-qPCR U+ Buffer contains an optimized buffer system and dNTP/dUTP Mix, which is particularly suitable for high specificity, low template concentration and multiplexed rapid detection of fluorescently labeled probes such as TaqMan. caveatBefore use, please mix the product gently by turning it up and down after it is completely melted to avoid foaming, and use it after brief centrifugation. Avoid repeated freezing and thawing of the product.ROX dye is used to correct the fluorescence signal error between the quantitative PCR wells, this product does not contain ROX dye, if you need to match the ROX dye with the instrument you are using, please contact your local business or call CombiSense customer service at 4006-222-360. PCR reaction system Attention: (1) Usually, the final primer concentration of 0.2 µM can get better results, and 0.1-1.0 µM can be used as a reference for setting the range. If the amplification efficiency is not high, the concentration of primer can be increased; if non-specific reaction occurs, the concentration of primer can be decreased to optimize the reaction system.(2) The final concentration of the probe used is related to the fluorescence quantitative PCR instrument used, the type of probe, and the type of fluorescent labeling substance, please refer to the instrument manual or the specific requirements for the use of each fluorescent probe to adjust the concentration.3) Because templates from different species contain different numbers of copies of the target gene, the template can be diluted in a gradient to determine the optimal amount of template to usePCR reaction conditionsmovetemptimingcirculatereverse transcription55°C1 min1premutability95°C10s1)1denaturation95°C1 s40-45Annealing/Extension55-60°C2)10-15s3)40-45Attention: (1) The enzyme used in this product is activated under the condition of pre-denaturation at 95℃ for 30s. Under this condition, most of the templates can be well unchained. For templates with high GC content and complex secondary structure, the pre-denaturation time can be extended to 1min, so as to make the starting template fully unchained, and if the high temperature treatment time is too long, it will affect the activity of the enzyme; for simple templates, pre-denaturation time of 1-10s can also be used, and the optimal pre-denaturation time can be determined according to the template situation.(2) It is recommended to use two-step PCR reaction program, the annealing temperature should be 55-60℃ as the reference range, and the annealing temperature can be increased when non-specific reaction occurs. If you can't get good results due to the use of primers with low Tm values or long amplification products, you can try three-step PCR amplification.3) Whether the actual Real Time PCR instrument used supports rapid amplification cycles, please perform a pre-experiment to verify this for the first attempt... Read More |