Effects of Enzymatic Hydrolysis Conditions on the Antioxidant Activity of Red Tilapia (Oreochromis spp.) Viscera Hydrolysates

Abstract

Background: Fish is an essential source of nutrients for human nutrition due to the composition of proteins, vitamins, minerals, among other nutrients. Enzymatic hydrolysis represents an alternative for the use of by-products of the aquaculture industry. Objective: We propose to evaluate the effect of stirring speed, temperature, and initial protein concentration on the degree of hydrolysis of proteins and antioxidant activity of red tilapia (Oreochromis spp.) viscera hydrolysates. Methods: The effect of stirring speed, temperature, and initial protein concentration on the degree of hydrolysis of proteins and antioxidant activity was evaluated using an experimental design that was adjusted to a polynomial equation. The hydrolysate was fractioned to determine the antioxidant activity of the fractions, and functional properties were also measured. Results: Stirring speed, protein concentration, presented a statistically significant effect (p <0.05) on all the response variables. However, the temperature did not present a statistically significant effect on the degree of hydrolysis. The best conditions of hydrolysis were stirring speed of 51.44 rpm, a temperature of 59.15 °C, and the protein concentration of 10 g L-1 . The solubility of the hydrolysate protein was high at different pH, and the hydrolysate fraction with the highest antioxidant activity has a molecular weight <1 kDa. Conclusions: The degree of hydrolysis and the biological activity of red tilapia viscera hydrolysates (Oreochromis spp.) are affected by temperature, substrate concentration, and stirring speed. The optimal conditions of hydrolysis allowed to obtain a hydrolysate with antioxidant activity that is due to the peptides with low molecular weight.

Use of Pacific thread herring ( Opisthonema libertate ) protein hydrolysates in Nile tilapia ( Oreochromis niloticus ) feeds: Productive performance and antioxidant enzymes on organisms exposed to a heat‐induced stress

“…Antioxidant activity has been reported to be dependent on several factors, mainly those related to chemical composition, such as amino acid (AA) content and molecular mass of peptides (Benjakul et al, 2014). In this study, the highest antioxidant activity exhibited by PH30, agrees with that reported by Sepúlveda and Zapata (2020) in red tilapia ( Oreochromis spp.) protein hydrolysates; this effect would be related to the diversity of the smallest peptides produced at high DH values, where in this study the PH30 had a higher percentage of the smallest peptides (<1.35 kDa) with respect to PH10 (Table 2).…”

Electrically Switchable Nanolever Technology for the Screening of Metal-Chelating Peptides in Hydrolysates

“…After loading, the cartridge was washed with the same eluent (3 mL), and TPH was then eluted with a mixture of 30% acetonitrile and 0.01% trifluoroacetic acid in water. The eluted desalted hydrolysate was then freeze-dried and stored at −20 °C until further analyses …”

“…The eluted desalted hydrolysate was then freeze-dried and stored at −20 °C until further analyses. 28 Peptide Characterization. Peptide concentration in hydrolysates (i.e., TPH and SPHs) was quantified using the ortho-phthaldialdehyde-based assay (OPA; ThermoFisher Scientific, Loughborough, UK) in the presence of N,N-dimethyl-2-mercaptoethyl-ammonium (ThermoFisher).…”

“…The eluted desalted hydrolysate was then freeze-dried and stored at -20 °C until further analyses. 28…”

Protein hydrolysates derived from aquaculture and marine byproducts through autolytic hydrolysis

“…Byproducts used as sources of proteins were from different species such as salmonids, tilapia, tuna, shrimp, mollusks, bivalves, and underutilized fish (Gómez et al., 2019; Ketnawa et al., 2018; Nikoo, Benjakul, Yasemi, et al., 2019; Nikoo, Benjakul, Gavlighi, et al., 2019; Opheim et al., 2015; Šližytė et al., 2017; Suresh et al., 2018; Suwal et al., 2018; Valcarcel et al., 2020; Vázquez et al., 2019, 2020; Zamora‐Sillero et al., 2018; Aspevik, Thoresen, et al., 2021; Aspevik, Steinsholm, et al., 2021; Camargo et al., 2021; Gheshlaghi et al., 2021; Hemker et al., 2020; Al Khawli et al., 2020; Korkmaz & Tokur, 2022; Rivero‐Pino et al., 2020a; Rodrigues et al., 2021; Sepúlveda & Zapata, 2020; Shafiee et al., 2021; Steinsholm et al., 2020; Tejpal et al., 2021; Vásquez et al., 2022; Wang et al., 2020). Several techniques have been used to produce protein hydrolysates from marine species and fisheries processing BPs.…”