Marine-derived bioactive peptides (MBPs) are emerging as promising natural agents for regulating inflammatory responses. MBPs, typically obtained through enzymatic hydrolysis of proteins from various marine organisms such as fish, mollusks, and algae, exhibit diverse biological activities, including antioxidant, immunomodulatory, and anti-inflammatory effects. The ability of MBPs to modulate key inflammatory mediators such as TNF-α, IL-6, and COX-2, primarily through pathways like NF-κB and MAPK, highlights the therapeutic potential of MBPs in managing chronic inflammatory diseases. However, most existing studies are confined to in vitro assays or animal models, with limited translation to human clinical applications. This review explores the stability, bioavailability, and metabolic rate of MBPs under physiological conditions, which remain poorly understood. In addition, a lack of standardized protocols for peptide extraction, purification, and efficacy evaluation hinders comparative analysis across studies and also different proteomics approaches for separation, purification, identification, and quantification of marine-derived peptides with therapeutic properties. The structure–function relationship of MBPs is also underexplored, limiting rational design and targeted applications in functional foods or therapeutic products. These limitations are largely due to a lack of consolidated information and integrated research efforts. To address these challenges, this review summarizes recent progress in identifying MBPs with anti-inflammatory potentials, outlines key mechanisms, and highlights current limitations. Additionally, this review also emphasizes the need to enhance mechanistic understanding, optimize delivery strategies, and advance clinical validation to fully realize the therapeutic potential of MBPs.

This study evaluated bioactive compounds in blood orange (Citrus sinensis (L.) Osbeck) peel (BOP) as dietary additives. An 8-week feeding trial was conducted to investigate the effects of dietary supplementation on the growth performance, body composition, digestive enzyme activity, antioxidant capacity, and immune response of juvenile black rockfish. A total of 1260 juvenile rockfish (1.4 ± 0.01 g) were randomly distributed into seven treatment groups, each with 50 fish per circular tank. The groups were fed seven different diets containing graded levels of 0 (control, BOP0), 1 (BOP1), 2 (BOP2), 3 (BOP3), 5 (BOP5), 7 (BOP7), and 10 (BOP10) g kg⁻¹, respectively. The BOP10 diet significantly enhanced the final weight, weight gain, specific growth rate, protein efficiency ratio, and protein retention in fish. The BOP treatments notably affected the fishes’ whole-body crude protein and lipid contents. Plasma total cholesterol levels of fish fed the BOP0 and BOP1 diets were significantly higher than those fed the BOP7 and BOP10 diets. The activities of trypsin and lipase were significantly affected by dietary BOP levels. The antioxidant enzyme activity in the plasma of fish fed the BOP10 diet was significantly higher than those fed the BOP0 diet. The lysozyme activity and levels of immunoglobulin M and G in fish fed the BOP0 diet were significantly lower than those in fish fed the BOP10 diet. In conclusion, dietary supplementation of BOP at 10 g kg⁻¹ improved the growth performance and overall health of juvenile black rockfish.

Fisheries and Aquatic Sciences

Fisheries and Aquatic Sciences

Background: A sea cucumber (Stichopus japonicus) is an invertebrate rich in high-quality protein peptides that inhabits the coastal seas around East Asian countries. Such bioactive peptides can be utilized in targeted disease therapies and practical applications in the nutraceutical industry. Methods: Bioactive peptides were isolated from Stichopus japonicus through ultrafiltration and Sephadex G-10 size exclusion chromatography. The low-molecular-weight fraction (ACSH-III) showed the highest hydroxyl radical scavenging and angiotensin-converting enzyme (ACE) inhibitory activities. Subsequent purification of ACSH-III resulted in four fractions, of which ACSH-III-F3 and ACSH-III-F4 exhibited significant bioactivity. Results: Peptides identified in these fractions, including Phenylalanine-Proline-Threonine-Tyrosine (FPTY) and Tyrosine-Proline-Serine-Tyrosine-Proline-Serine (YPSYPS), were characterized using high-performance liquid chromatography (HPLC) and quadrupole time-of-flight mass spectrometry (QTOF-MS). FPTY demonstrated the most potent antioxidant and antihypertensive activities among these peptides, with IC50 values of 0.11 ± 0.01 mg/mL for hydroxyl radicals and 0.03 ± 0.01 mg/mL for ACE inhibition. Docking simulations revealed strong binding affinities of these peptides to the active site of the ACE, with FPTY displaying interactions similar to those of the synthetic inhibitor lisinopril. Conclusions: These findings suggest that the identified peptides, particularly FPTY, have potential applications as natural antioxidants and functional foods.