Author(s): Li, Yu ; Su, Jing ; Castro, Tarsila Gabriel ; Cavaco-Paulo, Artur
Date: 2023
Persistent ID: https://hdl.handle.net/1822/83615
Origin: RepositóriUM - Universidade do Minho
Subject(s): Hair curling; Tyrosine grafting; Laccase; BSA; Molecular dynamics; 卷发; 酪氨酸接枝; 漆酶; 牛 血清蛋白; 分子动力学
Commercial hair perming uses strong reducing agents and harms hair fiber’s quality even human health. In this study, tyrosine is adopted as a crosslinking agent between thiols and/or amines as the shape-changing of hair involves the breakage of disulfide bonds and the rearrangement of new bonds between keratin molecules. To investigate the mechanism of keratin cross-linking, bovine serum albumin (BSA) is used as a model protein. Disulfide bonds in BSA are successfully reduced by L-cysteine to provide free thiols. Four new cross-linked peptides are formed inter- or intra-BSA monomers, indicating that tyrosine can be adopted as a cross-linking agent not only between amines but also between thiols. Moreover, curling of Asian hair is conducted using tyrosine as a perming agent by the laccase-assisted reaction. The optimized operational conditions are hair with L-cysteine pretreatment (50.0 mM) followed by laccase-assisted grafting with 3.0 mM tyrosine. The reshaped hair performed a better perming performance than commercial perming product before washing, although a lower perming efficiency after washing. The curling process could be accomplished without strength loss of hair fibers and with a blow-drier easily. Hence, this new methodology may lead to the development of a gentle and user-friendly approach in the hair care industry.
