Grass turtle muscle was hydrolyzed with papain enzyme to produce protein hydrolysate (PH) and the degree of hydrolysis (DH) was determined. Under optimal conditions, the highest DH was 19.52% and the yield was recorded as 17.26%. Protein content of the hydrolysates was ranged from 73.35% to 76.63%. Total amino acids were more than 96.77% for each PH. The PH obtained at DH 19.52% achieved excellent solubility and emulsifying activity which were 95.56% and 108.76 m²/g, respectively at pH 6. Foam capacity amounted 100% in PH of DH 19.52% at pH 2, and water‐holding capacity was 4.38 g/g. The antioxidant activity showed the strongest hydroxyl radical scavenging activity (95.25%), ABTS (84.88%), DPPH (75.89%), iron chelating (63.25%), and cupper chelating (66.90%) at DH 11.96%, whereas reducing power (0.88) at DH 19.52%. Thus, the findings indicated that utilization of grass turtle muscle protein hydrolysate is a potential alternative protein resource to improve the nutritional and functional properties in food ingredients and product formulations.

In the current study, bighead carp fish were used in conjunction with the flavourzyme enzyme to obtain (FPH) fish protein hydrolysates. The optimum conditions of the hydrolysis process included an enzyme/substrate ratio of 4% and a temperature of 50 °C and pH of 6.5. The hydrolysis time was studied and investigated at 1, 3, and 6 h, and the (DH) degree of hydrolysis was recorded at 16.56%, 22.23%, and 25.48%, respectively. The greatest yield value was 17.83% at DH 25.48%. By increasing the DH up to 25.48%, the crude protein and total amino acid composition of the hydrolysate were 88.19% and 86.03%, respectively. Moreover, more peptides with low molecular weight were formed during hydrolysis, which could enhance the functional properties of FPH, particularly the solubility property ranging from 85% to 97%. FTIR analysis revealed that enzymatic hydrolysis impacted the protein’s secondary structure, as indicated by a remarkable wavelength of amide bands. Additionally, antioxidant activities were investigated and showed high activity of DDPH radical scavenging, and hydroxyl radical scavenging demonstrated remarkable activity. The current findings demonstrate that the functional, structural, and antioxidant characteristics of FPH might make it an excellent source of protein and suggest potential applications in the food industry.

Heavy metals (HMs) contamination significantly threatens plants, animals, aquatic ecosystems, and public health. HMs’ accumulation in aquatic environments has become a serious environmental issue due to their high stability, bioaccumulation, and biomagnification properties. These metals enter ecosystems through both natural sources and/or human activities. The toxicity of HMs poses a threat to the aquaculture sector’s sustainability by negatively affecting fish growth, reproduction, and overall physiology. Exposure to HMs in various forms can cause environmental damage, which may affect human health through direct poisoning symptoms or other adverse effects. One such effect is the increased production of reactive oxygen species (ROS), crucial metabolites that modulate the functions of pathogenic organisms and lead to oxidative stress. This, in turn, can contribute to the onset and exacerbation of numerous diseases that threaten human health. This review article examines the potential sources of HMs contamination in aquatic organisms, the impact of this contamination on the generation of ROS, and the implications for human health resulting from the consumption of contaminated aquatic products.

Protein hydrolysates could be a natural and safer source of antioxidant peptides. The purpose of this study was to optimize the hydrolysis of Huso dauricus × Acipenser schrenckii sturgeon proteins using bromelain and purify antioxidant peptides from hydrolysate. The degree of hydrolysis of...