Mannoproteins (MP) are the part of cell walls and determine their enzymatic activity and structural and mechanical properties. Despite the insignificant content of protein in them, it is the protein that participates in the organization of the architecture of the cell wall by interacting with glucans and chitin. The type of glycosylation of proteins is important both for the manifestation of functional activity and for the choice of methods for extracting MP from cell walls. Among the variety of ways to release cells from the cytoplasm, yeast autolysis carried out by intracellular enzymes is recognized as the best. The choice of technology for the isolation of mannoproteins is determined by the efficiency of the process. The highest yield of MP was obtained by enzymatic hydrolysis. However, it has been established that other less effective methods make it possible to obtain fragments with important functional properties that are successfully used in the food industry, medicine, and animal husbandry. Depending on the molecular weight and the protein/mannan ratio, the drugs exhibit antimicrobial and prebiotic properties and are used as paraprobiotics with antimicrobial and prebiotic properties. They can be used as bioconservants in food as well as for the prevention and treatment of certain diseases.