Introduction: The objective of this study was to improve the economic value of the processed by-products of farmed miiuy croaker (Miichthys miiuy) by evaluating the nutrient composition and osteogenic activity of its bones. We prepared Miichthys miiuy bone peptides (MMBP) and analyzed their osteogenic potential.Methods: We assessed the osteogenic activity of MMBP by molecular docking, MC3T3-E1 cell proliferation assay and zebrafish growth model, and evaluated its effect on osteoporosis (OP) using a retinoic acid-induced osteoporosis rat model.Results: Sciaena ossificans bone is rich in nutrients, including 11.40% water, 59.30% ash, 1.60% crude fat, 27.10% crude protein, and 0.58% total sugars. The total amino acids account for 22.13%, including 4.33% essential amino acids and 17.80% non-essential amino acids. The mineral content was rich, with calcium, phosphorus and selenium contents of 162511, 7151, and 0.264 mg/kg, respectively. MMBP significantly promoted the proliferation of MC3T3-E1 cells, facilitated the growth and bone development of zebrafish. In retinoic acid-induced osteoporosis rat model, increased the serum calcium and phosphorus levels, attenuated the calcium loss, and reduced the tartrate-resistant acid phosphatase and alkaline phosphatase (ALP) activities and significantly improved bone density. MMBP shows potential as a functional food ingredient due to its osteogenic properties, which may help promote bone growth and maintain bone health. These findings provide a scientific basis for the high-value utilization of Miichthys miiuy by-products and a new direction for the development of novel functional food ingredients.

To evaluate the nutritional value and development potential of Pterocladiella capillacea in the marine environment of Naozhou Island, Zhanjiang, this study conducted species classification and identification, followed by an analysis of key nutritional components. The combination of morphological and molecular results confirmed the identification of the collected samples as P. capillacea. Further analysis showed that P. capillacea in Zhanjiang had a moisture content of 74.9% and a protein content of 24%. In comparison, the fat (0.4%) and carbohydrate (15.4%) contents were relatively low, with moderate ash (14.3%) and crude fiber (9.1%) content. It contains a diverse range of fatty acids, with saturated fatty acids accounting for 51.82% and unsaturated fatty acids accounting for 48.18% of the total. The amino acid composition was also diverse, with essential amino acids comprising 31.58% and flavor-enhancing amino acids constituting 54.85%. The minerals contained four major elements and four trace elements, while heavy metal levels were within safety limits, ensuring their edibility. In conclusion, P. capillacea is a high-protein, low-fat economic seaweed with a favorable amino acid and fatty acid composition, rich in minerals, and with significant nutritional and developmental potential. This study provides important data to support future research and utilization of this seaweed.