Extraction of Sericin from Cocoons of the Silkworm Bombyx Mori, Its Characteristics, and a Dietary Supplement on Its Basis to Prevent Diabetes Mellitus

A dietary supplement for the prevention of diabetes mellitus was obtained based on sericin separated from the cocoons of the silkworm Bombyx mori . By hydrolyzing Bombyx mori silkworm threads in an aqueous medium at a temperature of 110°C and a pressure of 0.143 MPa for 24 h, a sericin solution was separated. By evaporating the filtrate in a rotary evaporator, pure sericin powder with a molecular weight of 72 × 10 3 and a yield of 29.8% was obtained. Subsequent repeated hydrolysis of pure sericin powder with the indicated molecular weight in an aqueous medium at a temperature of 130°C and a pressure of 2.8 MPa for 120 min resulted in the isolation of sericin powder with a molecular weight of (5‒6) × 10 3 , containing free amino acids, with a yield of 18.6%. The amino acid composition, molecular weight, and functional groups of sericin were determined using high-performance liquid chromatography, viscometry, and Fourier transform infrared spectroscopy. Sericin samples with different molecular weights were tested on rats with nutritional hyperglycemia. When sericin, containing free amino acids with a molecular weight of (5‒6) × 10 3 , was administered at a dose of 65 mg/kg twice a day, a decrease by 159.5% in blood sugar levels in the rats was registered after 30 days compared to the control group.