Extraction and application of natural silk protein sericin from Bombyx mori as antimicrobial finish for cotton fabrics

Abstract

In this study, we developed an effective technology for the extraction of sericin from the cocoons of Bombyx mori silk worms. Sericin was extracted with ice cold ethanol to obtain crude extract. Sericin extract was coated onto cotton fabric by a pad–dry–cure method. FTIR characterization of the sericin-coated cotton fabric showed distinct amide peaks. The test organisms that were used in the study to assess the antimicrobial activity of sericin were Escherichia coli and Staphylococcus aureus according to AATCC standard. The antimicrobial activity of the sericin thus extracted was assessed by both qualitative (agar diffusion and parallel streak method) and quantitative (percentage reduction test) methods. An inhibition zone of 28 mm and 30 mm for E. coli and S. aureus by agar diffusion method and a zone of 40 mm and 42 mm for E. coli and S. aureus by parallel streak method were obtained. Quantitative assessment by percentage reduction test showed a reduction percentage of 89.4% and 81% for S. aureus and E. coli, respectively. Results suggested that sericin might be a valuable ingredient for the development of antimicrobial textiles.