Recent Advances in Environmentally Friendly and Green Degumming Processes of Silk for Textile and Non-Textile Applications

Abstract

Silk has been widely used not only in the textile field but also in non-textile applications, which is composed of inner fibrous protein, named fibroin, and outer global protein, named sericin. Due to big differences, such as appearance, solubility, amino acid composition and amount of reactive groups, silk fibroin and sericin usually need to be separated before further process. The residual sericin may influence the molecular weight, structure, morphology and properties of silk fibroin, so that degumming of silk is important and necessary, not only in textile field but also in non-textile applications. Traditional textile degumming processes, including soap, alkali or both, could bring such problems as environmental damage, heavy use of water and energy, and damage to silk fibroin. Therefore, this review aims to present a systematic work on environmentally friendly and green degumming processes of raw silk, including art of green degumming process, quantitative and qualitative evaluation, influence of degumming on molecular weight, structure, morphology and properties of silk. It is anticipated that rational selection and design of environmentally friendly and green degumming process is quite important and meaningful, not only for textile application but also for non-textile application.

Bromelain: a review of its mechanisms, pharmacological effects and potential applications

“…Bromelain offers a natural alternative to these chemicals as it can effectively remove sericin without causing damage to the fibres or the environment. 143 It works by breaking down the protein bonds in sericin, allowing it to be easily washed away. Additionally, bromelain was found to improve the dyeing quality of silk and wool fibres, making them more receptive to dyes.…”

“…Review linking of silk fibres, resulting in improved fibre properties such as increased strength and stability. 143 This has led to the development of new methods for producing high-quality silk fabrics that are both eco-friendly and cost-effective. Moreover, in the textile industry, bromelain was found to improve the dyeing quality of protein fibres such as wool and silk.…”

Silk‐based conductive materials for smart biointerfaces

“…69 Silk textiles are obtained by spinning SF fibers, which have a history dating back thousands of years. 70 Various natural or RSF fibers with special functions were designed and used to weave biomedical textiles. To meet practical needs, the silk fibroin used for textiles should be modified appropriately, involving structure/composition alterations in situ, and recombinations between molecules.…”

“…Silk fibroin‐based biomedical textiles were widely used as flexible electronics, 66 general surgery, 67 tissue engineering, 68 and esthetic surgery 69 . Silk textiles are obtained by spinning SF fibers, which have a history dating back thousands of years 70 . Various natural or RSF fibers with special functions were designed and used to weave biomedical textiles.…”

A high molecular weight silk fibroin scaffold that resists degradation and promotes cell proliferation

“…This process is usually accompanied by hydrolysis and damage to the peptide bond in the SF chain, thus resulting in a decrease in molecular weight (MW), destruction of the crystalline domain, and easy attack by proteases and subsequent biodegradation. [ 12 ] Freeze‐dried 3D scaffolds prepared by regenerated SF often exhibit the deficiencies of limited compressive strength and scaffold collapse due to easy local degradation. The repair period of dermal tissues is approximately 28 days.…”