Production and characterization of bioactive peptides from blue mussel shells

Abstract

Mussels, a popular global seafood choice, and the disposal of large amounts of mussel shells raise environmental concerns, prompting the industry to explore two main approaches, extracting calcium carbonate and valorizing the organic matrix composed of proteins, for more sustainable waste utilization. In this study we aimed to extract and characterize bioactive peptides from the blue mussel (Mytilus edulis) shells, contributing to an added-value upcycling of this waste stream. In terms of demineralization, the overall yield of extraction was 84.6%, as for the solubilization step, it was 53.2%, and for the hydrolysis, it obtained a global yield of 59.1%. The blue mussel shells peptides obtained exhibited antioxidant activities, namely 3.98 ± 0.41 µmol Trolox Equivalent/mg protein for ABTS method (2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) and 4.12 ± 0.22 µmol Trolox Equivalent/mg protein for ORAC method (oxygen radical absorbance capacity). The antihypertensive activity, determined by Angiotensin-converting enzyme (ACE) inhibitory activity, resulted in an IC50 of 805.7 ± 18.0 µg protein/mL. The peptide size composition of the obtained fractions characterized through High Pressure Size Exclusion Chromatography (HPSEC) revealed most of the peptides in the range between 1 and 3 kDa and under 1 kDa. Following the gastrointestinal simulation, the acquired peptides demonstrated antioxidant properties at the end of digestion, specifically 7.06 ± 1.96 µmol Trolox equivalents/mg of protein using the ABTS method and 4.38 ± 0.36 µmol Trolox equivalents/mg of protein using the ORAC method. This pioneering study allowed us to obtain a good yield of peptides from the blue mussel shell and demonstrated their bioactive potential.

Date of Award	14 Dec 2023
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Maria Manuela Pintado (Supervisor), Ezequiel Coscueta (Co-Supervisor) & Maria Paula Jauregui Torrecilla (Co-Supervisor)