Abstract
Quantification of carbohydrates by the anthrone method is a colourimetric
assay. In this method, first, the complex carbohydrates are hydrolysed in a highly
acidic medium, resulting in monosaccharides. Thereafter, these monosaccharides are
dehydrated to form 5-hydroxymethylfurfural (5-HMF) or 2-furfural (2-F), followed by
reacting with anthrone reagent. This reaction produces a blue-green complex which is
colourimetrically determined. In DNSA method 3,5-dinitrosalicylic acid (DNSA), a
yellow colour reagent reacts with reducing sugar’s carbonyl group and forms orangered colour compound 3-Amino-5-nitrosalicylic acid (ANSA). The quantity of
carbohydrate present in a sample is determined by Beer-Lambert’s law. Apart from
these techniques Folin-Wu, Hexokinase, Phenol-Sulphuric acid, Somogvi-Nelson, and
GOPOD method are discussed in this chapter in detail.