Production of Fish Protein Hydrolysates from Scyliorhinus canicula Discards with Antihypertensive and Antioxidant Activities by Enzymatic Hydrolysis and Mathematical Optimization Using Response Surface Methodology

Abstract

Fish discards are of major concern in new EU policies. Alternatives for the management of the new biomass that has to be landed is compulsory. The production of bioactive compounds from fish protein hydrolysates (FPH) has been explored in recent years. However, the viability of Scyliorhinus canicula discards, which might account for up to 90–100% of captures in mixed trawler, gillnet, and longline industrial fisheries, to produce FPH from the muscle with bioactivities has still not been studied in terms of the optimization of the experimental conditions to enhance its production. The effect of pH and temperature on the hydrolysis of the S. canicula muscle was mediated by three commercial proteases using response surface methodology. Temperatures of 64.6 °C and 60.8 °C and pHs of 9.40 and 8.90 were established as the best hydrolysis conditions for Alcalase and Esperase, respectively. Optimization of the best conditions for the maximization of antihypertensive and antioxidant activities was performed. Higher Angiotensin-converting enzyme (ACE) activity was found with Esperase. The pH optimum and temperature optimum for antioxidants were 55 °C/pH8.0 for ABTS/DPPH-Esperase, 63.1 °C/pH9.0 for DPPH-Alcalase, and 55 °C/pH9.0 for ABTS-Alcalase. No hydrolysis was detected when using Protamex.

Valorization of Aquaculture By-Products of Salmonids to Produce Enzymatic Hydrolysates: Process Optimization, Chemical Characterization and Evaluation of Bioactives

“…Optimization of salmonid heads hydrolysis was studied according to the factorial designs summarized in Table S1 (supplementary material) using a pH-stat system (100 mL reactor). Alcalase 2.4 L was chosen as biocatalyst due to its excellent capacity of proteolysis when it was applied to several marine substrates as squid pens, fish cartilages, crustacean shells, and other fish tissues and by-products [19][20][21][22]. A two-variable factorial design was executed in anticipation that no interactions among pH, T, r (S:L), and enzyme concentration were expected as it was reported by Liaset et al [3].…”

“…The hydrolysis degree (H, as %) was calculated according to the pH-Stat method [48] and the mathematical models previously reported [22]. The time course of H were fitted to the Weibull equation [27]:…”

Optimal isolation and characterisation of chondroitin sulfate from rabbit fish (Chimaera monstrosa)

“…At the end of the hydrolysis (6 h), samples were centrifuged (6000 g for 20 min) and liquid fractions (hydrolysates) stored at -18ºC until analysis. Degree of hydrolysis (H, as %) was quantified following the pH-Stat method (Adler-Nissen, 1986) and equations previously described (Vázquez, Blanco, Massa, Amado, & Pérez-Martín, 2017). Hydrolysis kinetics were finally modelled by Weibull equation (Vázquez et al, 2017):…”

“…has generally led to high hydrolysis values and complete digestion of solid cartilage. In the present study the enzyme selected is Esperase, a serine-type endoprotease which has shown high proteolytic activity on fish and cephalopod waste substrates (Akagündüz et al, 2014;Vázquez et al, 2017). Table for the enzymatic hydrolysis of C. monstrosa cartilage.…”

Conversion of Shrimp Head Waste for Production of a Thermotolerant, Detergent-Stable, Alkaline Protease by Paenibacillus sp.

“…Every year, the seafood processing industry discards a large amount of by-products, including viscera, shells, heads, squid pens, fins, and bones, even though they could be recycled to produce bioactive compounds like gelatin [1][2][3][4], enzymes [4][5][6][7][8][9][10][11][12][13][14][15][16][17], chitin [8,[18][19][20][21][22][23][24][25][26], chitin oligomers [7,11,12], α-glucosidase inhibitors (aGI) [27][28][29][30][31], carotenoids [32,33], and bioactive peptides [34][35][36][37][38][39][40]. Consequently, much research has gone into converting these by-products into bioactive products that have potential applications in biotechnological, agricultural, nutritional, pharmaceutical, and biomedical industries [1,…”