Biochemistry

varying degrees of branching and various molecular weights. In the largest amount, glycogen is present in the liver (up to 15% of the mass), muscles (2-4%), its content in other organs (brain, cardiac muscle) is small. With a lack of glucose, it quickly breaks down and restores its normal level in the blood. In cells, glycogen is bound to a protein of the cytoplasm and partially to intracellular membranes. Inulin consists mainly of residues of 0-fructose molecules. Being a reserve energy material of plants, inulin accumulates in tubers of earthen pear, dahlia, roots of kok-sagyz, chicory. During hydrolysis, it breaks down to f-fructose . Inulin tastes sweet, so it is used in the diet of patients with diabetes to replace sucrose and starch. Cellulose (fiber) Се H10O5 is widespread in the plant world. It is the main structure of the cell walls, determining their strength and elasticity. Cellulose consists of a- and f - D- glucose residues in f-pyranose form , linearly interconnected by (1 — > 4) bonds . These linear molecules are parallel to each other, hydrogen bonds arise between them and microfibrils form. With partial hydrolysis of cellulose , cellobiose disaccharide is released , and with complete hydrolysis, D- glucose is formed . Fiber is not digested in the human gastrointestinal tract due to the absence of P-glucosidase. However, it is necessary for normal digestion , as it stimulates the motor activity of the intestine and gall bladder, improves the advancement of food gruel along the digestive canal, enhances the excretion of bile from the gall bladder, and promotes the formation offeces and their excretion from the intestine. With insufficient fiber in the diet, a person develops constipation, conditions arise that stimulate the intestinal mucosa and its inflammation. When fiber interacts with acids and alcohols, various esters are formed. Using these reactions, cellophane, celluloid, photographic film, explosives are obtained. Carboxymethyl cellulose (KM cellulose) and diethylaminoethyl cellulose (DEAE cellulose), which are used for the separation of amino acids, proteins, nucleic acids, are widely used in ion exchange chromatography. In addition, KM cellulose is used in the clinical nutrition of obese people to reduce the calorie content of food. The structural polysaccharide is chitin. It is part of lower plants (in particular, fungi) and invertebrates. Chitin consists of 2-acetamide-2-deoxy- D- glucose residues linked by P-l,4-bonds. Pectin substances are polysaccharides of plant origin. They are high molecular weight compounds found in large quantities in berries, fruits and vegetables. As monomer residues contain D -galacturonic acid. 150