Production of crude chondroitin sulfate from duck trachea

This work was aimed to study the preparation and hydrolyzation of cartilage from duck trachea to obtain crude chondrotin sulfate(CS). Duck trachea is comprised of 66.19 ± 0.96% protein and 3.46 ± 0.15% CS (dry basis). HPLC chromatograms revealed that CS of duck trachea contained higher content of ΔDi-4S than ΔDi-6S with trace amount of ΔDi-diSs. To obtain cartilage part of the trachea, use of alkaline (0.05-0.1MNaOH at 4oC and RT for 1-6 h), enzyme (0.1-0.5% alcalase for 1-6 h) and heat (boiling for 1-120 min) treatments were studied. Heating by boiling in water caused the least CS loss among all studied treatments. The cartilage prepared by heat treatment was subjected to papain digestion (0.0625-1.0% for 1-10 h) and the yield, type and size of obtained CS were evaluated. The CS samples from 0.0625-0.25% papain hydrolysis for 1-10 h were similar in size (15-40 kDa). Up to 80% of CS was extracted by 0.25% papain digestion for 10 h. The freeze-dried hydrolysate from trachea cartilage contained 10.6% CS which was concentrated to 39% after protein precipitation.