Recovery of Collagen from Phosphonium Tanned Leather Shavings and Application as Formaldehyde Scavenger

摘要

Samples of collagen extracted from phosphonium tanned leather shavings by three different methods (acid, alkali, magnesium oxide dissolution and alkaline protease hydrolysis treatments) were characterized with respect to their components and morphology of fibril network. The ratio of collagen gained was 90% by the process of alkali dissolution and enzyme hydrolysis, which was much higher than that of acid and alkali methods. The results from amino acid analysis showed that the components of extracted collagen were similar with that of commercial gelatin. The Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) results indicated that the extracted substance was the mixture of polypeptide and amino acid. The polypeptide and amino acid exposed to hydrophilic functional groups including carboxyl, hydroxyl, amino group etc. These functional groups especially amino group can react with formaldehyde which leads to scavenge formaldehyde. The morphological change of leather shavings treated by magnesium oxide and alkaline protease was clearly presented with scanning electron microscope. The percentage of formaldehyde removal and thickening rate of collagen were 51.8% and 10.4%, respectively. Therefore, the collagen from the leather shavings and used as the formaldehyde scavenger has a good potential in achieving the innocent treatment and reuses of the solid leather wastes.