Proteomic Identification and Characterization of Collagen from Bactrian Camel (Camelus bactrianus) Hoof

Abstract

With the development of camel-derived food and pharmaceutical cosmetics, camel hoof, as a unique by-product of the camel industry, has gradually attracted the attention of scientific researchers in the fields of nutrition, health care, and biomaterial development. In this study, the protein composition and collagen type of Bactrian camel hoof collagen extract (CHC) were analyzed by LC-MS/MS, and the functional properties of CHC were further investigated, including its rheological characteristics, emulsification and emulsion stability, and hygroscopicity and humectancy. Proteomic identification confirmed that CHC had 13 collagen subunits, dominated by type I collagen (α1, α2), with molecular weights mainly in the 100–200 KDa range and a pI of 7.48. An amino acid study of CHC revealed that it carried the standard amino acid profile of type I collagen and was abundant in Gly, Pro, Glu, Ala, and Arg. Additionally, studies using circular dichroism spectroscopy and Fourier transform infrared spectroscopy revealed that CHC contains a collagen-like triple helix structure that is stable and intact. Different concentrations of CHC solutions showed shear-thinning flow behavior. Its tan δ did not differ much with increasing concentration. The CHC has good emulsifying ability and stability, humectancy, and hygroscopicity. This study provides a basis for utilizing and developing Bactrian camel hoof collagen as a functional ingredient.

Effect of pH on the Structure, Functional Properties and Rheological Properties of Collagen from Greenfin Horse-Faced Filefish (Thamnaconus septentrionalis) Skin

“…The extraction yields of Megalonibea fusca swim bladders collagen (33.38%) [8] and double-spotted pufferfish (Takifugu bimaculatus) skin collagen (49.83 ± 1.85%) [9] were higher than those of cattle tendon collagen (2.4-6.2%) [10], pork skin collagen (11.38% ± 0.66%) [11] and sheep slaughter by-product collagen (12.05%) and lamb slaughter by-product collagen (18.0%) [12]. The emulsifying activity index of collagen of red stingray (Dasyatis akajei) skin collagen (61.06-117.11 m 2 /g) [13] was superior to that of bactrian camel (Camelus bactrianus) hoof collagen [14] and rabbit meat collagen (44.7 m 2 /g), rabbit skin collagen (46.6 m 2 /g), rabbit ear collagen (48.2 m 2 /g) [15] and lamb slaughter by-product collagen (59.1 m 2 /g) [12]. The emulsifying stability index of double-spotted pufferfish skin collagen (45.23-13.68 min) [9] was higher than that of rabbit meat collagen (9.8 min), rabbit skin collagen (9.8 min), and rabbit ear collagen (9.8 min) [15].…”