Bone‐strengthening effects and safety of compound peptides from skin of Chiloscyllium plagiosum and Mustelus griseus

Abstract

Fish processing produces a lot of by‐products highly containing large amount of proteins which mainly consist of collagen, implying great potential value for application as nutraceutical ingredients. In present study, two kinds of sharks, Chiloscyllium plagiosum and Mustelus griseus, were used as raw material to gain three kinds of “compound peptides” (CPs) by enzymolysis, FCP (CPs from the flesh of C. plagiosum), SCP (CPs from the skin of C. plagiosum), and SMG (CPs from the skin of M. griseus). According to a series of constituent analysis, the molecule weights of FCP, SCP, and SMG were under 800 Da; amino acids composition analysis of FCP, SCP, and SMG showed that there were high glycine, proline, and hydroxyproline and low cysteine contents in SCP and SMG, which is the characteristic of collagen peptides; their total protein contents were 87.500%, 91.875%, and 95.625%, respectively; and heavy metal contents of CPs were all beneath national standards. After three kinds of CPs were administrated intragastrically to C57BL/6 mice at a total dosage of 15 g/kg, bone‐strengthening effects of SCP and SMG were manifested by osteoblasts activity promotion, bone mineral density (BMD) increase, and marrow adipocyte number decrease, yet nonsignificant effects were shown in FCP group. No index showed toxicity of SCP and SMG in subacute toxicology trial, indicating their safety as functional foods. Herein, industrial application foundation of the skins from these two sharks was explored but more efforts should subsequently be implemented for further exploitation.

Protective effects of orally administered shark compound peptides from Chiloscyllium plagiosum against acute inflammation

“…The preparation and characterization of shark compound peptides (SCP) from C. plagiosum have been reported before (Xu et al., 2020). In brief, the skin of C. plagiosum was defrosted under room temperature (RT) and cleaned with ultrapure water before being cut into about 1 × 1 cm small pieces.…”

“…The mass of total protein in the sample was 91.5 g/100 g. The molecular weight distribution of SCP was determined by MALDI‐TOF‐MS. The SCP mainly consists of dipeptides, tripeptides, and tetrapeptides (<500 dalton) (Xu et al., 2020).…”

“…The by‐products of the shark consist of heads, viscera, and skin. We have recently reported the extractive procedure of the shark compound peptides (SCP) from skin of C. plagiosum and found that oral administration of the SCP was nontoxic and possessed bone‐strengthening effects in mice (Xu et al., 2020). In this study, we attempted to further investigate the immunoprotection potential of SCP against exaggerated inflammatory responses stimulated by acute infections in murine models, so as to evaluate the possibility of utilization of SCP as novel diet supplementation for preventing inflammatory diseases.…”

Developments for Collagen Hydrolysate in Biological, Biochemical, and Biomedical Domains: A Comprehensive Review

“…ingestion of three novel compound peptides from sharks [31]. Another researcher also reports mice as subjects for analysis of skin impairments [42].…”

“…Halim et al presents the novel Asian swamp eel hydrolysate as a food stabilizer and emulsifier with good emulsification and foaming properties [ 30 ]. Xu et al uses two types of sharks to make three novel collagen peptides for osteoblast activity [ 31 ]. The resulting collagen peptides reveal a molecular weight of <800 Da with high mineral bone density and osteoblast proliferation [ 31 ].…”