Production of Collagens and Protein Hydrolysates with Antimicrobial and Antioxidant Activity from Sheep Slaughter By-Products

Abstract

This work aimed to produce collagens and hydrolysates with antimicrobial and antioxidant activity from sheep slaughter by-products. The by-products (sheep and lamb) were treated and extracted. The collagens were hydrolyzed with the enzyme Alcalase®. The spectra of collagens and hydrolysates were similar (amide bands I, II, III, A, B). The bands presented by the collagens (α1, α2, β) were characteristic of type I collagen. The hydrolysates showed molecular weight peptides equal to/lower than 15 kDa. Collagens had a denaturation temperature of 39.32 (lamb) and 36.38 °C (sheep), whereas the hydrolysates did not undergo thermal transition. Hydrolysates showed lower values of antioxidant activity (AA) than the collagens. The collagens from lamb and from sheep displayed an AA of 13.4% (concentration of 0.0002%) and 13.1% (concentration of 0.0005%), respectively. At the concentration of 0.0020%, the lamb hydrolysates displayed an AA of 10.2%, whereas the sheep hydrolysates had an AA of only 1.98%. Collagen also showed higher antimicrobial activity compared to hydrolysates, requiring a lower concentration to inhibit the microorganisms tested. Sheep slaughter by-products proved to be a viable source for obtaining protein hydrolysates and collagens with antimicrobial and antioxidant activity, which can be applied in the development of nutraceuticals beneficial to human health.

Expression, characterization, and application potentiality evaluation of recombinant human-like collagen in Pichia pastoris

“…Collagen can be hydrolysed into low molecular weight peptides rich in glycine, which would make them biologically active (Ahmed et al 2020 ). Thus, collagen hydrolytic peptides are an important by-product with many applications in the medical (Feng and Betti 2017 ), tissue repair (Sivaraman and Shanthi, 2021 ), beauty and food (Vidal et al 2022 ; Zhang et al 2018 ) industries. The molecular weight of most of these collagens was less than 2000 Da (Hong et al 2019 ).…”

Preparation and tissue structure analysis of horse bone collagen peptide

“…Likely, a longer reaction resulted in more enzymolysis products and complexes, which inhibited the enzymolysis reaction, decreased the reaction speed, and thus decreased the yield. Furthermore, the peptide's reaction site becomes saturated over time; some peptides are decomposed into amino acids, and the decomposition rate exceeds the protein peptide formation rate, decreasing the peptide yield (Vidal et al 2022). We also found that the short peptide yield increased and then decreased as the temperature increased, peaking at 50 ℃ (yield: 63.78%).…”

Antimicrobial and Antioxidant Properties of Bovine Livers and Hearts Hydrolysates

“…The minimum inhibitory concentration value was 1.25 µg/mL in both cases of bovine liver and heart hydrolysates. Antimicrobial activity may have been influenced by the size of the resulting peptides [37]. Kim and Wijesekara have reported that antibacterial activity can be observed in low molecular weight peptides (less than 10 kDa) that possess a positive charge and are made of amphipathic molecules [38,39].…”