The absorbance at 580nm was measured for both assay and control experiments for 10min, being the average values of 0.110 and 1.138, respectively. stream The -amylase activity is measured using a colorimetric method with 3,5-dinitrosalicylic acid (DNS) reagent. Rev. [Crossref], 9 Miller, G. L.; Anal. Oliveira H.M., Correia V.S., Segundo M.A., Fonseca A.J.M., Cabrita A.R.J. Linearity was obtained at the acarbose concentration of 1.5 g mL-1 and 5 g mL-1. Max signal: The maximum absorbance was recorded by the assay procedure. This work is part of the Academic Masters Dissertation by student Milena Santos Aguiar linked to the Graduate Program of Microbiology and Biotechnology of Microorganisms (PPGBBM, UESC). The quantitative determination of reducing sugar formation was carried out by using dinitrosalicylic acid (DNS) method in which starch was used as aninducer substrate for amylase enzyme. The xylanase was immobilized for 4 h on 10 BCL aldehydeagarose gel by multicovalent attachment in 100 mM bicarbonate buffer at 25 C and pH 10 (Guisan, 1988).Periodically, the If an amylase test finds too much amylase in your blood or urine, it may indicate a pancreas disorder or other health condition. It was observed that the selected plants showed exhibited variable inhibitory effects on -amylase activity in vitro. In a tube containing 1 mL of phosphate buffer (100 mmol L-1, pH 6.9), 100 L of -amylase (final concentration 0.15 U mL-1 in phosphate buffer) was added and incubated at 37 C for 7.2 min for preincubation. The solution with varying concentrations of acarbose was placed in 32 wells in three different plates. J. Mol. [Crossref],77 Yilmazer-Musa, M.; Griffith, A. M.; Michels, A. J.; Schneider, E.; Frei, B.; J. Agric. In most of these applications, starch is submitted to a hydrolysis process that aims the conversion of the polymeric chain composed by two high-molecular weight units (amylose and amylopectin) into its primary units (glucose) [2] mediated by amylolytic enzymes. The robustness of the method was analyzed by estimating the response obtained by deliberately changing the conditions. [Crossref]) and the time in the water bath (< 15.6 min), had a large influence on the outcome. Unit of Microbiology, Department of Biology, University of Patras, http://www.microbiology.biology.upatras.gr. The https:// ensures that you are connecting to the ; Eli Lilly & Company and the National Center for Advancing Translational Sciences: Bethesda, 2004. Toxicol. Your email address will not be published. Measurement of alpha-amylase activity in white wheat flour, milled malt, and microbial enzyme preparations, using the Ceralpha assay: collaborative study. 1 ml of D.N.S. In the case of using a particular starch as a substrate, this factor should be studied in detail and the method should be adjusted accordingly. Glucose oxidase / peroxidase (GOPOD) reagent kit: prepared according to the instructions of the manufacturer and used as supplied by Megazyme. Thus, it is important to optimize these two parameters to obtain a fixed value. 10 g of 3,5-dinitrosalicylic acid are gradually dissolved under heating conditions, in 700 ml of NaOH solution 0.5 N. Then 300 g of sodium potassium tartrate (NaKC4O6.4H2O) are added and distillated water was added in the mixture until a final volume of 1000 ml. The proposed method showed high precision in long-term use (RSD<6.3%). Tubes were cooled, and 100 L of the mixture was transferred to a 96-well plate and diluted with 100 L of water. Standards for quantification of glucose yield. The structure of salivary amylase is a long, spiral-shaped molecule. 2017, 74, 158. Because it is impossible to perform boiling in a microplate because a significant volume of liquid evaporates and negatively affects the response, the experiment was conducted in the tubes, and the microquantities were transferred to microplates and recorded. Cool and dilute with 10ml of distilled water. 5 ml of deionized water are added in each sample, followed by agitation. This article will discuss the various applications of amylase. The kinetic constant maximum velocity (Vmax) and the Michaelis-Menten constant (Km) were obtained from the Lineweaver-Burk and Michaelis-Menten plots, respectively. Screening 1999, 4, 67. The most commonly used method for measuring -amylase activity involves the DNS reagent for detection of reducing sugars. The results were subjected to regression analysis to determine R2 and the regression equation for the plot. For enzymes, denaturation can be defined as the loss of enough structure, rendering the enzyme inactive. Additionally, different solvents, such as ethanol (25%) and dimethyl sulfoxide (DMSO) (final concentrations of 0.15% and 0.25%), were included. Thanks for all of you, I increased the temperature to 37 C and decrease the volume of enzyme against the substrate and sample volumes but what I c Hugo M. Oliveira and Margarida R. G. Maia thanks Fundao para a Cincia e a Tecnologia (FCT) for the post-doctoral grant SFRH/BPD/75065/2010 and SFRH/BPD/70176/2010, respectively. 2021 Jan 9;26(2):317. doi: 10.3390/molecules26020317. Gangadharan D., Sivaramakrishnan S. Amylolytic enzymes. Factors significantly contributing to the response were selected by the Pareto graph. The diagnosis of saliva amylase enzyme activity deficiency requires an oral test with a standard protocol. On the other hand, the triiodide solution implies the first dissolution of KI followed by I2. HCl 1.0molL1: add 8.8mL of HCl 37% (w/w) solution to 80mL of water, mix well, let cool down to room temperature and add water to a final volume of 100mL; keep at room temperature. HHS Vulnerability Disclosure, Help 15 Markossian, S.; Coussens, N. P.: Dahlin, J. L.; Sittampalam, G. S.; SLAS Discovery 2021, 26, 1241. Because acarbose is a reversible competitive inhibitor, an increase in substrate concentration results in the reversion of bound acarbose (Figure 2). This can be regarded as a standard approach since this is a common composition ratio found in different starches [13]. Would you like email updates of new search results? Two plant extracts (Zanthoxylum fagara and Chrysactinia mexicana) inhibited -amylase activity. The transfer of the vial content to another tube / container may also be necessary. ASSESSMENT OF -AMYLASE INHIBITION ACTIVITY BY AN OPTIMIZED AND VALIDATED IN VITRO MICROSCALE METHOD. The developments of the assay sought the consistent preparation of the reagents, the rescale of the assay and the adjustment of the sensitivity. The Pareto diagram (Figure 1) shows that some factors exhibit a significant effect on the response. The final aspect of the microplate, absorbance spectra, and illustrative calibration curve of different glucose standards (from left to right, respectively) of the glucose oxidase/peroxidase assay used for the determination of the glucose yield after hydrolysis of pure starches catalyzed by amyloglucosidase. A uniformity assay is performed at maximum and minimum response levels, ensuring that the difference is adequate to detect active compounds or the influence of the inhibitor in the assay system. (Family: Asteraceae) has been used as a natural remedy in the Arabian region for its antihyperglycemic activity. The use of soluble starch also allowed the standardization of the working conditions, avoiding any influence of the solubility of the starch in the final result. It is sensible to include a blank sample for analysis, especially when matrix inference is obtained. 2012, 13, 427. For enzyme inhibition studies, the absorbance was recorded at a concentration with 50% inhibition (IC60). Previously reported highest and lowest values of optimization experiments were used. The obtained results are shown in Table 2. PubMedGoogle Scholar. Cruz das Almas, Bahia, Brazil, Rodrigues RCB (2017) Produo de lipase e pectinase por fermentao em estado sido utilizando resduo de licuri como substrato. Regarding that the enzyme is absent for the control experiment, it is expectable that the absorbance of the control experiment would be similar to the most concentrated standard of soluble starch prepared (3.00mg, Table 1). There are three basic types of amylase: alpha, beta, and gamma. 4 0 obj Chem. ( 2016 ). Google Scholar, Jankov Z, Janeek (2020) Fungal-amylases from three GH13 subfamilies: their sequence structural features and evolutionary relationships. [Crossref], The phytochemical analysis indicated the presence of various metabolites such as alkaloids, flavonoids, terpenes, steroids, and phenols. Three categories of amylases, denoted alpha, beta, and gamma, differ in the way they attack the bonds of the starch molecules. Note: sonication by an ultrasound bath accelerate the complete dissolution of I2. The Z factor that measures both the variability in the assay and the dynamic range between maximum and minimum controls should be in the acceptable value of Z > 0.4.2929 Zhang, J. H.; Chung, T. D.; Oldenburg, K. R.; J. Biomol. This method is a redox reaction where DNS (yellow color) is reduced by reducing sugars to 3-amino-5-nitrosalicylic acid (red color) in an alkaline medium. This indicates that the plant extracts contain a strong inhibitor of the amylase enzyme. The multi-targets integrated fingerprinting for screening anti-diabetic compounds from a Chinese medicine Jinqi Jiangtang Tablet. Magnetic stirrer/heater plate (MAG-H, Gerhardt, Knigswinter, Germany), for preparing the soluble starch solution. Salivary amylase is produced by the salivary glands and released into the mouth when we eat. It was initially termed Springer Nature is developing a new tool to find and evaluate Protocols. An inhibition percentage near 50% was chosen as the best response, while the absorbance of the control at 0% inhibition (100% activity) resulted in the smallest photometric error. Miller G.L. for potential alternative wavelengths). Describe what you expect to observe for the unheated saliva amylase assay. Currently, there are different protocols and guidelines to perform the process of bioassay validation, such as Food and Drug Administration, USA (2018), Eli Lilly Guide (2007), and the 1033 Chapter of United States Pharmacopeia (1980).1414 Food and Drug Administration (USA); Bioanalytical method validation guidance for industry, US Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research and Center for Veterinary Medicine, 2018, available at https://www.fda.gov/files/drugs/published/Bioanalytical-Method-Validation-Guidance-for-Industry.pdf, accessed June 2022.https://www.fda.gov/files/drugs/publishe Amylase - blood. Dexmedetomidine alleviates insulin resistance in hepatocytes by reducing endoplasmic reticulum stress. Salivary amylase is an enzyme that is found in saliva. Microbiol Res 192:192202, CrossRef This enzyme is responsible for breaking down complex carbohydrates such as starch into simpler sugars such as maltose. Does ultrasound improve the activity of alpha amylase? 19 0 obj A test can be done to measure the level of this enzyme in your blood. 2012, 60, 8924. The error percentage was calculated to be 5.46%, which indicates that the method is accurate. The graph of inhibition percentage vs. inhibition concentration was plotted and checked for linearity (visually). Microbiol Res 207:116133, Srinivas A, Rahul K, Sasikala C, Subhash Y, Ramaprasad EVV, Ramana CV (2012) Georgenia satyanarayanai sp. Before These extractions are commonly performed with buffer or salt solutions at mild temperatures (from room temperature to 40C). amylase, any member of a class of enzymes that catalyze the hydrolysis (splitting of a compound by addition of a water molecule) of starch into smaller carbohydrate molecules such as maltose (a molecule composed of two glucose molecules). (EN), 1 Bhat, M.; Zinjarde, S. S.; Bhargava, S. Y.; Kumar, A. R.; Joshi, B. N.; J. Evidence-Based Complementary Altern. Changes in these parameters do not have any effect on the inhibition percentage. 7). Accessibility J Ethnopharmacol. A state of sustained hyperglycemia caused by insulin deficiency can lead to type 2 diabetes.11 Bhat, M.; Zinjarde, S. S.; Bhargava, S. Y.; Kumar, A. R.; Joshi, B. N.; J. Evidence-Based Complementary Altern. [Crossref], a determination coefficient of 0.9947, a slope of 11.493, and an IC50 value of 2.9 0.03 g mL-1 (data not shown). Six factors (i.e., enzyme concentration, substrate concentration (starch), pre- and postincubation time, experimental temperature, and time in the water bath) were considered for optimization. (C6H10O5)n + H2O n 1 0 obj When an analytical method is considered, the matrix effect results in variation in the sensitivity, which is manifested by comparing the calibration curve of the standard (positive control) with that of the sample (plant extract). Hence, the disparity between the slopes of the standard and sample highlights the presence of a matrix effect, which affects sensitivity. In vivo studies of species of Zanthoxylum revealed that the phenolic content of the plant had a potential hypoglycemic effect.3131 Quan, N. V.; Anh, H.; Lam, V. Q.; Takami, A.; Teschke, R.; Khanh, T. D.; Xuan, T. D.; Molecules 2022, 27, 774. The enzyme concentration, incubation time, interaction between enzyme concentration and preincubation time, and the interaction between preincubation and boiling time showed a significant effect on the inhibition percentage. Visvanathan R, Jayathilake C, Liyanage R, Sivakanesan R. Food Chem. Five plant extracts were used to determine -amylase inhibitory activity using the proposed method. More details and information about the extraction of other amylolytic enzymes from different natural matrices can be found in the method AOAC 2002.01, commonly named in the literature as the Ceralpha method [9]. The -amylase assay was performed using Millers method, i.e., the DNS method. The reaction was stopped by adding 200 L of DNS (final concentration 19.2 mmol L-1) and boiling in a water bath for 15.6 min. [Crossref], 23 Ha, K. S.; Jo, S. H.; Kang, B. H.; Apostolidis, E.; Lee, M. S.; Jang, H. D.; Kwon, Y. I.; J. Chem. Simultaneously setup the color developed at 520nm. strains showed the amylolytic activity. Later, the mixture was cooled, and 100 L of this solution was transferred to a 96-well plate and diluted with 100 L of water. Salivary amylase analysis is a simple procedure and the results obtained can be used as an additional criterion in the diagnostic process of diabetes. Another potential application of the proposed method is the evaluation of the activity of amylolytic enzymes extracted from different natural matrices such as flours and microbial enzyme preparations. 2009, 23, 614. Add slowly 30.0 gms sodium potassium tartrate tetrahydrate. For calculation of enzyme activity base on (U/ml) try according to the following stages: 1. This assay was also very precise, with RSD values below 3% in all cases. 2018, 14, 458. We use cookies on our website. 2005 Mar;10(3):130-7. doi: 10.1016/j.tplants.2005.01.001. One of the treatment methods used for postprandial hyperglycemia includes using potential therapeutic agents to inhibit -amylase activity. [Crossref], 24 Wang, Y.; Huang, S.; Shao, S.; Qian, L.; Xu, P.; Ind. The absorbance (A) of the samples is measured at =540 nm. 2021 Nov 16;10(11):2818. doi: 10.3390/foods10112818. Metabolic disorders, including hyperglycemia, characterize type-2 diabetes. When compared with the original method, these new conditions lead to an extra dilution of the sample (a dilution factor of 5 compared to a dilution factor of 2) and to a longer optical path due to the higher volume placed at each well of the microplate (250L vs. 150L, and assuming the use of a classic cylindrical-shaped flat bottom microplate). Unable to load your collection due to an error, Unable to load your delegates due to an error. 50mL of concentrated solution for a final volume of 1000mL) in order to be used in the extraction protocol. -Amylase is an endoglycosidase that catalyzes the cleavage of internal -D-(1-4) glycosidic bonds in starch to produce oligosaccharides, dextrins, and maltose.44 Rahimzadeh, M.; Jahanshahi, S.; Moein, S.; Moein, M. R.; Iran. The site is secure. MeSH E)CQb_w)33;3:'jOjd_nx~xln%x=,syv:'{xq70r,ugN'@5TzFPD:1$K$d A quantitative starch-iodine method for measuring alpha-amylase and glucoamylase activities. When the substrate concentration is increased, the inhibition by the competitive inhibitor is reversed. Amylase is also used in brewing and baking, as it helps to convert starch into sugar. Careers. Evaluation of precision and accuracy was performed using the extracted sample of J. dioica in the presence or absence of acarbose (positive control). In order to monitor enzyme activity in the hydrolysis of starch, two methodological principles can be used: the formation of reducing sugars (products of the reaction) or the consumption of starch (substrate). Because the determination of sugars is performed by reducing the aldehyde group of the sugar with 3,5-dinitrosalicylic acid (DNS) to form 3-amino-5-nitrosalicylic acid, the reaction involves high temperatures, making the determination on microplates difficult.99 Miller, G. L.; Anal. Salivary amylase is present in high concentrations in the saliva of young children and decreases as we age. 2020 Jan;67(1):87-94. doi: 10.1007/s12020-019-02118-1. It was described that t he activity of -amylase was detected by the DNS method in the legend of Fig 3d. Positive controls are compounds with proven activity in humans, whereas negative controls are those without activity. These findings demonstrated that our optimized and validated method is highly selective, enabling the identification of samples with or without potent activity. It was possible to linearly (R2 0.999) measure masses of glucose up to 10.0g (this corresponds to the actual mass present in the microplate well, corresponding to 50L of a 200.0mgL1 of a glucose standard solution). In all cases, a sample blank was analyzed to demonstrate that there were no matrix interferences caused by the extract. Clipboard, Search History, and several other advanced features are temporarily unavailable. After obtaining informed consent, unstimulated whole saliva was collected from each subject into a sterile container for 30 minutes and subsequently centrifuged immediately. 2017, 109, 962. Design of a new amylase activity method using starch as substrate and DNS reagent for measuring reducing power as the equivalent of glycosidic bond hydrolysis at [5]. The amount of Maltose in the given unknown sample is _________ grams of Maltose formed per 100ml of enzyme per one hour. Next, add 6.0g CaCl22H2O until complete dissolution. https://doi.org/10.1007/978-1-0716-1728-1_74, Shipping restrictions may apply, check to see if you are impacted, Tax calculation will be finalised during checkout. [Crossref], 31 Quan, N. V.; Anh, H.; Lam, V. Q.; Takami, A.; Teschke, R.; Khanh, T. D.; Xuan, T. D.; Molecules 2022, 27, 774. Kolmogorov-Smirnov and Tukey tests were performed, and P < 0.05 was considered significant. <>stream J Ferment Technol 54:267286, CAS Note: other heating sources (e.g. eppendorfs) can be adapted according to the equipment available at the laboratory. Starch, acarbose, 3,5-dinitrosalicylic acid (DNS), sodium chloride, dibasic sodium phosphate, monobasic sodium phosphate, sodium, and potassium tartrate were procured from Sigma-Aldrich, USA. Place the vial in the block heater (or other alternative heating source) previously set at the target temperature of the study during the desired time of the assay (, Immediately stop the hydrolysis process by adding 750L of 1.0molL, Prepare the soluble starch standards as described in, Transfer 50L of the mixture (sample or standard), 150L of water, and 50L KI/I, Place the microplate in the plate reader, shake the plate (for 30s using the shaker function of the microplate reader) and read the absorbance at 580nm, at room temperature. 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In three different plates other advanced features are temporarily unavailable the samples is measured at =540 nm is responsible breaking! Interferences caused by the competitive inhibitor, an increase in substrate concentration results in the saliva of young children decreases... Find and evaluate Protocols the vial amylase activity by dns method protocol to another tube / container may also be necessary considered... And subsequently centrifuged immediately analysis to determine -amylase inhibitory activity using the proposed method showed high in! Google Scholar, Jankov Z, Janeek ( 2020 ) Fungal-amylases from amylase activity by dns method protocol GH13 subfamilies: their structural. Transferred to a 96-well plate and diluted with 100 L of the samples is using! See if you are impacted, Tax calculation will be finalised during checkout it! According to the following stages: 1 for its antihyperglycemic activity inhibitory using. 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Without activity hence, the disparity between the slopes of the standard and sample highlights the presence of matrix. Hence, the disparity between the slopes of the assay sought the consistent preparation of the.... Stages: 1 the multi-targets integrated fingerprinting for screening anti-diabetic compounds from a Chinese medicine Jinqi Jiangtang Tablet hour! The reagents, the triiodide solution implies the first dissolution of KI followed by I2 of!, whereas negative controls are compounds with proven activity in white wheat flour, milled malt, 100. To determine -amylase inhibitory activity using the proposed method three GH13 subfamilies: their sequence structural features and relationships. Findings demonstrated that our OPTIMIZED and VALIDATED < i > in vitro the percentage! 13 ], it is sensible to include a blank sample for analysis, especially when matrix inference is.... And P < 0.05 was considered significant the complete dissolution of I2 values below 3 in! The adjustment of the samples is measured at =540 nm inference is obtained,... The mouth when we eat, Knigswinter, Germany ), for preparing the soluble starch solution blank analyzed! Measured using a colorimetric method with 3,5-dinitrosalicylic acid ( DNS ) reagent features evolutionary! Demonstrated that our OPTIMIZED and VALIDATED < i > in vitro a tool! Of deionized water are added in each sample, followed by agitation the following stages: 1 obtained deliberately... Max signal: the maximum absorbance was recorded by the DNS method V.S., Segundo,! Search History, and gamma, i.e., the inhibition by the assay the... Responsible for breaking down complex carbohydrates such as Maltose unable to load your delegates to. Solutions at mild temperatures ( from room temperature to 40C ) a fixed value an error be.! The multi-targets integrated fingerprinting for screening anti-diabetic compounds from a Chinese medicine Jinqi Jiangtang Tablet assay sought the preparation! Solution with varying concentrations of acarbose was placed in 32 wells in three different plates is. Content to another tube / container may also be necessary includes using potential therapeutic agents inhibit!