Eco-sustainable silk sericin from by-product of textile industry can be employed for cosmetic, dermatology and drug delivery

BACKGROUND: In the last decade, many researchers demonstrated the biological activities of native Bombyx mori silk sericin (SS), and its use is widespread in the cosmetic and biomedical field. However, SS is a polluting material from the silk fibroin textile industry. This paper aims to demonstrate that the industrial wastewater-derived SS has many biological properties, and can be used as an eco-friendly product for cosmetic/pharmaceutical purposes with an important impact on the circular economy. RESULTS: We focused on the SS derived from an ad hoc extraction process or industrial degumming wastewater. Both products were preserved with three different methods: lyophilization, spray-drying and sterilization. All SS were characterized in terms of amino acid content, molecular weight, physical–chemical properties, morphology and size distribution; then we evaluated the biological properties, the cytocompatibility/cytoprotective profile, and the immunomodulatory abilities of SS. Free radical scavenging, anti-tyrosinase, and anti-elastase activities of waste SS were confirmed. Waste and standard SS were cytocompatible on human fibroblasts; all SS samples inhibited the proliferation of stimulated peripheral blood mononuclear cells in a dose-dependent manner. Waste SS showed a significant effect on tumor necrosis factor α and interleukin 10 release. CONCLUSIONS: These results pave the way for using textile wastewater-derived SS to obtain high-value-added products for cosmetic and/or pharmaceutical purposes.