High Molecular Weight Sericin Obtained by High Temperature and Ultrafiltration Process

详细信息    查看全文

• 作者：V.R. Silva ; M. Ribani ; M.L. Gimenes ; A.P. Scheer
• 关键词：Silk cocoon ; Sericin ; Degumming process ; Ultrafiltration ; Perrmeate flux
• 刊名：Procedia Engineering
• 出版年：2012
• 出版时间：2012
• 年：2012
• 卷：42
• 期：Complete
• 页码：905-918
• 全文大小：434 K

文摘

Sericin is a water-soluble protein derived from silkworm Bombyx mori, represents about 30 % of the cocoon weight and consists of 18 kinds of amino acids, with strong polar side groups, especially acid aspartic and serine. These contribute for many physical and biological properties like: antioxidant activities; suppress of lipid oxidation and inhibit of tyrosinase activity. The aim of this study was to evaluate different extraction process and recovering the high molecular sericin with Ultrafiltration process. Sericin was extracted from Bombyx mori cocoons, at different temperatures and different cocoons concentrations. Sericin solution was treated by ultrafiltration process with polysulfone membrane of 50 kDa, feed flow of 1.0 and 2.0 L min^-1, concentration in sericin solution of 0.1 g L^-1 and1.0 g L^-1, at different transmembrane pressure. The temperature showed strong influence in the degumming process by hot water while the cocoon concentration did not have statistically significant influence in the extraction. The highest values extraction, 22.5 ¡À 0.4 % and 24.5 ¡À 0.4 % , were obtained at 120 ?C and 127 ?C, respectively, with molecular weight distribution between 200 kDa and 100 kDa, while the extraction with Na2CO3 showed extraction yield of 30.1 ¡À 0.9 % , but molecular weight lower than 50 kDa. In ultrafiltration process, the sericin concentration has significant influence; while the feed flow did not have significant influence in permeate flux. High transmembrane pressure increased the resistance of permeability, reducing the permeate flux. The maximum value of permeate flux for sericin solution of 0.1 g L^-1 was 104.6 ¡À 9.7 kg m^-2 h^-1 obtained with transmembrane pressure of 0.15 MPa, while for the sericin solution of 1.0 g L^-1 the permeate flux was statistically equal for 0.05 MPa, 0.07 MPa and 0.09 MPa. The permeate solution showed molecular distribution lower than 50 kDa, while the retentate solution showed the molecular weight distribution about 200 kDa.