Pérez-Gálvez Raúl, Espejo-Carpio F Javier, García-Moreno Pedro J, Guadix Antonio, Guadix Emilia M
Department of Chemical Engineering, Faculty of Sciences, University of Granada, 18071 Granada, Spain.
Antioxidants (Basel). 2025 Jun 23;14(7):770. doi: 10.3390/antiox14070770.
This study aimed to produce antioxidant peptide fractions from Skipjack tuna () head by-products through enzymatic hydrolysis and membrane filtration. Raw materials were sequentially hydrolyzed with Alcalase (4 h) and Flavourzyme (1 h), reaching a final degree of hydrolysis of 18.5 ± 0.9%. The crude hydrolysate was fractionated using ceramic membranes with molecular weight cut-offs of 8, 3, and 1 kDa. Some peptide fractions presented a relevant proportion of short-chain peptides (>50% /) and free amino acids (>10% /), as well as a high content of essential amino acids (>64% mol), supporting their value as dietary ingredients for aquafeeds. In vitro antioxidant activities were assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferrous ion chelation assays. Some fractions (e.g., F3R1 with IC = 1.04 ± 0.01 mg·mL for metal chelating activity) displayed significantly improved ( < 0.05) antioxidant properties compared to the unfractionated hydrolysate (IC = 2.75 ± 0.08 mg·mL). This may be linked to their molecular weight profile and hydrophobic amino acid content. These results demonstrate the potential of the proposed approach to obtain bioactive peptide fractions with functional properties for aquafeeds. Zootechnical trials are needed to assess their effects on feed utilization and in vivo mitigation of oxidative stress.
本研究旨在通过酶解和膜过滤从鲣鱼（）鱼头副产物中制备抗氧化肽组分。原料依次用碱性蛋白酶（4小时）和风味酶（1小时）水解，最终水解度达到18.5±0.9%。粗水解产物使用截留分子量为8、3和1 kDa的陶瓷膜进行分级分离。一些肽组分呈现出较高比例的短链肽（>50% /）和游离氨基酸（>10% /），以及高含量的必需氨基酸（>64%摩尔），这支持了它们作为水产饲料膳食成分的价值。通过2,2-二苯基-1-苦基肼（DPPH）自由基清除和亚铁离子螯合试验评估体外抗氧化活性。与未分级的水解产物（IC = 2.75±0.08 mg·mL）相比，一些组分（例如，金属螯合活性的IC = 1.04±0.01 mg·mL的F3R1）表现出显著改善（<0.05）的抗氧化性能。这可能与其分子量分布和疏水氨基酸含量有关。这些结果证明了所提出的方法在获得具有水产饲料功能特性的生物活性肽组分方面的潜力。需要进行动物饲养试验来评估它们对饲料利用率和体内氧化应激缓解的影响。
