Table 3 shows the yield of the collagen. The yield of collagen in shark skin was higher compared to Tuna and Rohu
skin. The skin was not completely solubilized with 0.5 M acetic acid even with two repetitions of extraction except
for tuna skin. This result suggested a high amount of cross-links at the telopeptide region as well as other intermolecular
cross-links, leading to low solubility of collagen in acid [20].