3.10. Effect of NaCl concentration on solubility of collagens All ASC and PSC showed nearly similar solubility characteristics with different NaCl concentrations (Fig. 9). All collagens (ASC and PSC) ex- hibited high solubility (76-100%) at NaCl concentrations up to 0.4 M. The solubility of all collagens (ASC and PSC) decreased sharply with NaCl concentrations >1 M and after which the solubility remained at constant low rate (Fig. 9). Similar findings on the effect of NaCl concen- tration on collagen solubility have been reported by various research groups (Li et al., 2013; Liu et al., 2012; Matmaroh et al., 2011; Minh Thuy et al., 2014). The decline in solubility of collagens with the increase of NaCl concentration might be due to the protein precipitation and salting-out effect. The differences in structure and amino acid composi- tion also have an impact on the solubility of collagens, especially at high NaCl concentrations (Minh Thuy et al., 2014). The solubility characteris- tics of collagens with changes in NaCl concentrations may play a crucial role in their extraction and application in various sectors.