Microbial Biomass as a Bioresource of Functional Food Ingredients: A Review

Microbial biomass is a promising source of essential macro- and micronutrients to be used in the food industry, e.g., protein, vitamins, essential amino acids, polysaccharide, etc. This article reviews scientific publications on the properties and composition of microbial biomass as a source of functional ingredients, its biological effectiveness, production methods, and composition. The review covered research articles published in 2005–2021 and indexed in eLIBRARY.RU, Google Scholar, Scopus, Elsevier, and PubMed. It relied on such general scientific methods as analysis, generalization, and systematization. Saccharomyces cerevisiae yeast and Aspergillus mycelial fungi appeared to be the most popular research objects. Most studies concentrated on the chitin-glucan-mannan complex of cell walls and protoplasmic biovaluable protein. Others featured the biocatalytic conversion of microbial polymers with the transfer of biologically valuable components into an enzyme-accessible state. Bioactive ingredients of microbial origin could be divided into sorbents, immunomodulators, neurotransmitters, antioxidants, and anticarcinogenics. Microbial fermentolysates are a potential source of bioactive compounds for functional foods. However, the medical and biological properties of their minor bioactive components remain understudied while fermentolysates can yield new functional products fortified with essential amino acids and low-molecular bioactive peptides.