Sustainable utilization of proteins from fish processing by-products: Extraction, biological activities and applications

The intersection of population growth, resource scarcity, and climate change has created formidable obstacles to ensuring global food security. Simultaneously, a rising consumer demand for safe, nutritious diets has spotlighted the significance of "blue foods," particularly nutrient-rich and easily digestible fish and fish products. Within this context, the by-products of fish processing—comprising skin, viscera, scales, heads, bones, and fins—emerge as valuable reservoirs of proteins. To address the imperative of 'zero waste' and embrace a 'biorefinery for high-value compounds' approach, it becomes crucial to methodically extract and synthesize proteins from these by-products. This not only holds the potential to bolster the global economy but also aligns with environmental sustainability goals, reducing pollution and fostering a trajectory towards sustainable development. This review endeavors to delve into recent literature focusing on the extraction and utilization of proteins from fish by-products obtained by chemical hydrolysis, enzymatic hydrolysis, fermentation, or other methods. In addition, this study will explore the biological activities and applications of these proteins in medical tissue engineering, food, and cosmetics. Extensive research findings highlight the manifold beneficial activities of proteins derived from fish by-products, showcasing their potential in health promotion, disease prevention, and therapeutic interventions. These proteins exhibit a broad spectrum of applications, ranging from health pharmacology to food supplements and pharmaceuticals. However, to comprehensively understand their mechanisms and ascertain their market potential, further in vivo and clinical trials are imperative. This exploration is essential not only to harness the full spectrum of marine resources but also to stimulate the growth of the blue bioeconomy. By unlocking the potential of fish by-products, people can contribute to global sustainable development and foster common prosperity.