The Characterization of Acid Soluble Collagen from Sheep Tail Tendon

Abstract

The sheep (Ovis aries) tail tendons are the major by-products after being slaughtered for food consumption. A tendon is a powerful band of fibrous connective tissue that is composed of parallel bundles of collagen fibers and connects muscle to bone, due to the transmit forces and tolerate tension during muscle contraction. The tendon collagen structure is found as the main molecule of dense fibrous tissue and forms approximately 70% of dry weight. The collagen type is largely composed of Type I (60%) and other types. Type I collagen is by far the most abundant molecules in vertebrates, and it is a particularly mechanical scaffold in bone, skin, and connective tissue. This study was conducted to extract and characterize acid-soluble collagens (ASC) from sheep tail tendons. The tendon collagen was confirmed as collagen by different physicochemical techniques such as sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Zeta Potential Analyzer, and Fourier transform infrared (FTIR) spectra analysis. The yield of type I ASC from sheep tail tendon was about 9.7% on the dry weight of raw material. The collagen’s α1, α2, and β chain bands are observed in SDS-PAGE for both ASC and pepsin soluble collagen. The zeta potentials of ASC had a positive charge when pH from 2 to 4.5, while the negative charge in pH range from 6 to 11. But the electric potential of ASC was zero at pH 5. The results of FTIR spectra analysis detected the presence of triple superhelical structure in acid-soluble collagens, presenting isolation procedure did not interrupt the triple helical structure from the sheep tail tendon. Therefore, the study showed that it is a potential reference for collagen extraction and application of sheep tendon tails.