Assessment of the biological activity of fish muscle protein hydrolysates using in vitro model systems.

• Processing conditions have major effects on bioactivity of fish protein hydrolysates. • Low molecular weight fish hydrolysates generally exhibit enhanced bioactivities. • Identification of bioactive peptide(s) from fish protein hydrolysates is limited. • Animal and human studies on fish muscle hydrolysates/peptides are required. The generation of biologically active fish protein hydrolysates (FPH) is a useful technique to produce value-added products with potential application in the functional food and nutraceutical industries. Fish muscle is an attractive substrate for the production of protein hydrolysates due to its rich protein content, containing 15–25% of total fish protein. This paper reviews the production of protein hydrolysates from fish muscle, most commonly via enzymatic hydrolysis, and their subsequent bioactivities including anti-obesity, immunomodulatory, antioxidant, angiotensin I‐converting enzyme (ACE)-inhibitory, anti-microbial, and anti-cancer activities as measured by in vitro testing methods. Disease prevention with FPH potentially offers a safe and natural alternative to synthetic drugs. Small molecular weight (MW) FPHs generally exhibit favourable bioactivity than large MW fractions via enhanced absorption through the gastrointestinal tract. This review also discusses the relationship between amino acid (AA) composition and AA sequence of FPH and peptides and their exhibited in vitro bioactivity. [ABSTRACT FROM AUTHOR]