Sucrase Isomaltase Deficiecncy

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Sucrase isomaltase deficiency is a disorder that affects normal carbohydrate digestion and therefore absorption, and leads to sucrose intolerance. Intolerance is described as clinical symptoms that are caused by sugar malabsorption (Scriver et al, 2001), in the case of sucrose intolerance this refers to the inability to digest and absorb sucrose, leading to several abdominal symptoms. Although sucrase isomaltase deficiency is not a fatal condition, it can cause suffers discomfort and therefore changes to the diet need to be made in order to avoid the symptoms caused by the deficiency.

Carbohydrate accounts for about half of the energy humans get from food. Carbohydrate digestion and absorption takes across the brush-border member which has an apical and basolateral membrane. Anchored to the brush-border membrane are enzymes that are involved in digesting disaccharides (Silverthorn, 2010). Carbohydrates can only be absorbed as monosaccharaides meaning polysaccharide and disaccharide carbohydrates must first be hydrolysed into monosaccharaides.

Carbohydrate digestion begins in the saliva and stomach where alpha-amylase hydrolyses alpha-1, 4 glycosidic bonds between glucose molecules in starch, forming maltotriose, the disaccharide maltose and dextrin’s made of five to ten glucose molecules (Lim, 2007). The disaccharides sucrose and lactose come directly from food. There are four enzymes found on the brush-border membrane responsible for hydrolysing sucrose, lactose and the products of starch break down, into monosaccharaides so that they can be absorbed (Lieberman et al, 2007). These enzymes are known as glycosidases and include; glucoamylase, lactase, trehalase and sucrase isomaltase (Lieberman et al, 2007). Sucrase isomaltase...

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