Determination of reducing sugars using dns

The problems associated with the DNS assay have also been reported by other researchers [ 9 — 11 ]. Our data on CMCase activities of twelve enzyme preparations determined with two different RS assays Table 1 are very similar to those reported by Breuil and Saddler [ 11 ], who observed moderate overestimations of the endoglucanase CMCase activity of Trichoderma harzianum culture filtrates by the DNS assay in comparison with the NS assay. Nevertheless, both methods gave comparable results for the CMCase activity values of the same decimal magnitude that should not cause any serious ambiguities if data from different laboratories, obtained with either DNS or NS assay, are analyzed. In particular, cellulase complexes produced by Trichoderma sp.

Determination of reducing sugars using dns

The problems associated with the DNS assay have also been reported by other researchers [ 9 — 11 ]. Our data on CMCase activities of twelve enzyme preparations determined with two different RS assays Table 1 are very similar to those reported by Breuil and Saddler [ 11 ], who observed moderate overestimations of the endoglucanase CMCase activity of Trichoderma harzianum culture filtrates by the DNS assay in comparison with the NS assay.

Nevertheless, both methods gave comparable results for the CMCase activity values of the same decimal magnitude that should not cause any serious ambiguities if data from different laboratories, obtained with either DNS or NS assay, are analyzed.

In particular, cellulase complexes produced by Trichoderma sp. The situation with activities of other carbohydrases determined using the DNS assay is more serious. Twenty laboratories participated in this collaborative investigation; thirteen of them used the DNS assay while three laboratories used the NS assay.

The activity values obtained with the DNS assay were 3- to 8-fold higher than those obtained with the NS assay.

Determination of reducing sugars using dns

However, in spite of the evident drawbacks of the DNS assay, it has been accepted for measuring xylanase activity by most laboratories in the world. Other examples of poor applicability of the DNS assay for measuring carbohydrase activity against some polysaccharides may be given.

The reason for dramatic overestimations of the carbohydrase activities by the DNS method is the polysaccharide instability under severe conditions of the assay. The DNS reagent seems to be the most destructive for polysaccharides, as our Table 1 and the literature data [ 9 — 11 ] indicate.

The polysaccharide degradation under alkaline conditions at high temperature occurs by means of two major mechanisms: For this reason, both the DNS and NS assay cannot be applied for measuring pectinase activity against pectins esterified polygalacturonates.

Nevertheless, examples of the questionable use of the DNS assay for measuring pectinase activity may be found in the scientific literature [ 1617 ]. At the same time, polygalacturonic acid, free of the methyl ester groups, can be used as a substrate in determination of the polygalacturonase activity with an RS assay.

In this case, the interpretation of experimental data obtained by both methods should not cause ambiguities. However, the DNS assay gives 3- to 6-fold overestimations of xylanase activity against glucuronoxylan compared to the NS assay.

So the comparison of data reported from different laboratories should be taken with care. Both methods cannot be applied for measuring pectinase activity against methylated pectins. A classification of glycosyl hydrolases based on amino acid sequence similarities.

Industrial Enzymes and Their Applications. A photometric adaptation of the Somogyi method for the determination of glucose. Journal of Biological Chemistry.

Notes on sugar determination. Use of dinitrosalicylic acid reagent for determination of reducing sugar. A new reaction for colorimetric determination of carbohydrates.

The determination of reducing sugars by titration of ferricyanide. Reducing value methods for maltodextrins.The determination of lactose in dairy product is important and there are The DNS method for estimating the concentration of reducing sugars in a sample Reducing sugars contain free carbonyl group, have the property to reduce many of the reagents.

Determination of Redusing Sugar Using Dns Method Essay. The production of reducing sugars by acid of carbohydrate cereals powder, jams (total sugar content) and jams (reducing sugar content) were performed in order to study reducing sugar production - Determination of Redusing Sugar Using Dns Method Essay introduction.

3,5-Dinitrosalicylic acid (DNS) is used in colorimetric determination of reducing sugars and to analyze glycosidase (glycoside hydrolase) activity by quantitation of enzymatically released reducing sugar.

Determination of reducing sugars using dns

The dinitrosalicylic acid method has been compared to the Nelson-Somogi colorimetric method. Reducing sugars concentrations were determined by spectrophotometry using the 3, 5 dinitrosalicylic acid (DNS) method. The first sample was operated as blank for . Type part of your institution name for a list of matches.

If your institution is not listed, please contact your librarian. Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar. ADVERTISEMENT. Log In Register. Cart Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar.

G. L. Miller. Anal. Chem., , 31 (3), Suitability of Low-Cost Sugars as Substrates for Lipid Production by the Fungus Thamnidium elegans.

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