This book is concerned with experiments and methodology of carbohydrate with illustrated examples, graphs and charts. This textbook is useful for graduate and post graduate students.
Table of Contents
1. Carbohydrate
1.1 Introduction
1.1.1 Classification of Carbohydrate
1.1.2 Monosaccharide
1.1.3 Oligosaccharide
1.1.4 Dissacharide
1.1.5 Trisaccharide
1.1.6 Polysaccharide
1.1.7 General Properties
1.1.8 Physical Properties
1.1.9 Chemical Properties
1.2.1 Acetylation
1.2.2 Formation of Glycoside
1.2.3 Formation of salts
1.2.4 Reduction
1.2.5 Oxidation
1.2.6 Formation of Cyanohydrin
1.2.7 Formation of Oximes
1.2.8 Formation of osazones
1.3.1 Tetroses
1.3.2 Pentoses
1.3.3 Hexoses
2. To perform Molisch test for given sugar solution
3. To perform Seliwanoff’s test for given sugar solution to distinguish Ketoses from aldoses
4. To perform Benedicts test for given sugar solution to distinguish reducing sugar from non reducing sugar
5. To perform Bial’s test for given sugar solution to distinguish pentoses from hexoses
6. To perform Mucic Acid test for given sugar solution to distinguish pentoses from other hexoses
7. To perform Barfoed test for given sugar solution to distinguish monosaccharides from disaccharides
8. To perform Fehling’s test for given sugar solution to distinguish reducing from from non reducing
Objective and Thematic Focus
This work provides a comprehensive overview of carbohydrate chemistry and details various experimental procedures used for their detection and classification. The central aim is to equip the reader with the theoretical understanding and practical laboratory techniques required to identify, differentiate, and estimate different types of sugar molecules.
- Fundamental chemical properties and classification of carbohydrates
- Mechanisms of monosaccharide reactions, including oxidation and osazone formation
- Standard qualitative diagnostic tests for sugar identification
- Quantitative estimation methodologies using spectrophotometry
- Distinction between reducing and non-reducing sugars
Excerpt from the Book
1.2.8 Formation of osazones
Monosaccharides when treated with phenylhydrazine they yield diphenylhydrazone which are known as osazone. According to the mechanism suggested by Fischer, a phenylhydrazone is first produced and then the hydroxyl group adjacent to the original aldehyde or the ketonic group is oxidized to a carbonyl group adjacent to the original aldehyde or the ketonic group is oxidized to a carbonyl group by a second molecule of phenylhydrazine which is reduced to aniline and ammonia. The carbonyl group thus produced now reacts with a third molecule of phenylhydrazine to yield the osazone. It is found that the osazone obtained from glucose and fructose are identical Since the two sugars form the same osazone their structure differ only in respect of two carbon atoms which take part in the formation of osazone. Osazone are yellow crystalline solids having sharp melting points. Their formation is used to characterize the sugar.
Summary of Chapters
Carbohydrate: Provides an introduction to the chemical structure of carbohydrates and their classification into monosaccharides, oligosaccharides, and polysaccharides.
To perform Molisch test for given sugar solution: Describes the general qualitative test for the presence of carbohydrates, which relies on the formation of a purple complex.
To perform Seliwanoff’s test for given sugar solution to distinguish Ketoses from aldoses: Explains the procedure for differentiating ketose sugars from aldose sugars using a resorcinol-based reaction.
To perform Benedicts test for given sugar solution to distinguish reducing sugar from non reducing sugar: Details the method for identifying reducing sugars based on the reduction of copper ions.
To perform Bial’s test for given sugar solution to distinguish pentoses from hexoses: Outlines the specific test using orcinol to distinguish between five-carbon and six-carbon sugars.
To perform Mucic Acid test for given sugar solution to distinguish pentoses from other hexoses: Details the use of nitric acid to identify galactose through the formation of specific crystals.
To perform Barfoed test for given sugar solution to distinguish monosaccharides from disaccharides: Provides a methodology for differentiating simple monosaccharides from complex disaccharides based on acidity levels.
To perform Fehling’s test for given sugar solution to distinguish reducing from from non reducing: Describes a sensitive test for detecting reducing sugars using copper-based reagents and Rochelle salt.
Keywords
Carbohydrates, Monosaccharides, Disaccharides, Polysaccharides, Molisch Test, Seliwanoff’s Test, Benedicts Test, Bial’s Test, Mucic Acid Test, Barfoed Test, Fehling’s Test, Osazone, Glycosidic Linkage, Aldose, Ketose
Frequently Asked Questions
What is the core subject of this document?
The document focuses on the chemical analysis of carbohydrates, covering both their theoretical classification and the experimental laboratory procedures for their identification.
What are the primary thematic areas covered?
The main themes include structural classification, chemical properties (such as reduction, oxidation, and osazone formation), and practical analytical tests for various sugar types.
What is the primary objective of this work?
The primary objective is to provide a guide for scientists and students on how to identify and distinguish different classes of sugars in solution using standardized biochemical tests.
Which scientific methods are employed?
The work utilizes standard biochemical qualitative analysis techniques, including dehydration and condensation reactions, as well as quantitative estimation using the Anthrone method.
What topics are discussed in the main body?
The main body covers the nomenclature of carbohydrates, their properties, and step-by-step laboratory protocols for tests like Molisch, Seliwanoff’s, Benedicts, Bial’s, and Barfoed’s.
Which keywords characterize this work?
Key terms include carbohydrates, monosaccharides, various chemical identification tests (Molisch, Fehling, etc.), and structural characteristics like glycosidic linkages.
How is the osazone test used to identify sugars?
The osazone test produces distinctive yellow crystalline solids that allow researchers to characterize specific sugars, as different sugars form identical or distinct crystal shapes based on their structure.
What is the significance of the Anthrone method?
The Anthrone method is used for the quantitative estimation of total carbohydrates, providing a spectrophotometric approach to measure concentration based on color intensity at 620 nm.
- Quote paper
- Dr. Ekta Prakash (Author), 2014, Analysis and Experiments of Carbohydrate, Munich, GRIN Verlag, https://www.grin.com/document/284516
