Effect of ultrasound-assisted extraction on the extractability and physicochemical properties of acid and pepsin soluble collagen derived from Sharpnose stingray (Dasyatis zugei) skin

This study aims to investigate the effect of ultrasound-assisted extraction on the extractability and physico-chemical properties of acid (UASC) and pepsin (UPSC) soluble collagen derived from Sharpnose stingray (Dasyatis zugei) skin. Pre-treated skins were extracted using 0.5M acetic acid under ultrasonication for UASC, and 0.5M acetic acid with 1.5% (w/w) pepsin under ultrasonication for UPSC. The yield of UPSC (61.50 +/- 0.79%) was higher than UASC (42.34 +/- 0.62%) while, no significant different in chemical compositions except for protein content between UASC and UPSC. The enzymatic hydrolysis results in the molecular weight of alpha-2 chain for UPSC. Freeze dried UASC and UPSC had similar morphological structures, with loose, irregular dense sheet-like film and irregular pore size. The extracted UASC and UPSC were thermally stable, with high thermal denaturation (T-d), and had no significant differences in their maximum temperature (T-max). UASC and UPSC also showed highly solubilized at acidic pH range and had the lowest solubility at pH 8. In conclusion, ultrasound-assisted extraction showed a potential technique to improve the yields of collagen extracted without affecting other properties of Sharpnose stingray collagen.

Automated summary

This study investigated the effect of ultrasound-assisted extraction on the extractability and physico-chemical properties of acid and pepsin soluble collagens from Sharpnose stingray skin. The results showed higher yield of pepsin soluble collagen compared to acid soluble collagen, with similar chemical compositions and thermal properties between the two types of collagen.