Bioactive peptides and proteases: characteristics, applications and the simultaneous production in solid-state fermentation

Bioactive peptides are compounds hydrolysed from an inactive parental protein that has beneficial effects on health, such as reduction of blood pressure, antioxidant activity, reduction of problems caused by diabetes, anticancer action, among others. These compounds can be obtained by the hydrolysis of proteins by enzymes, as the proteases, which are produced by microorganisms through solid-state fermentation. Solid-state fermentation (SSF) has been widely used to produce enzymes and other biocompounds due to advantages as simplicity, the possibility of using residues as substrates, allowing the reduction of environmental pollution, the addition of value to these residues, and lower costs in the process. SSF also allows the simultaneous production of proteases and bioactive peptides, optimising the process and reducing antinutritional compounds, such as allergens. This work aimed to review the literature on the production of proteases and bioactive peptides through solid-state fermentation, including the simultaneous production of these compounds, since the fermented medium can benefit from the hydrolysis capacity of the enzymes produced by microorganisms. Normally, obtaining these compounds has been studied in an isolated way and not concomitantly in a single bioprocess, being this the main differential of our review.