Extraction and characterisation of telopeptide-poor collagen from porcine lung

The aim of the investigation was to develop optimum extraction conditions of telopeptide-poor collagen from porcine lung (TPCPL). Chemical composition, histological properties of porcine lung, removal efficiency of haemoglobin by different solvents and effects of pepsin solubilisation time on TPCPL properties were evaluated. Histological observation of lung tissue revealed collagen coexists with elastin. Treatment with 0.1 M Tris–HCl/5% Triton X-100 (pH 8.2) for 12 h exhibited the highest efficiency for removal of haemoglobin. The maximal yield of TPCPL reached 6.702 g/kg by pepsin solubilisation for 72 h. SDS–PAGE indicated that type I collagen was a major component of TPCPL; FTIR spectra of all TPCPL were similar to commercial porcine collagen and absent from denatured product (gelatin) and TPCPL 72 exhibited the lowest denaturation temperature (36.4 °C) and maximum enzymatic sensitivity. Finally, the optimum pepsin solubilisation of TPCPL was controlled at 4 °C for 48 h for better structural integrity and acceptable yield.