Color fastness and antimicrobial activity of Gardenia jasminoides extract against antimicrobial-resistant Staphylococcus aureus

This study investigated the antimicrobial efficacies of fabrics (100% cotton and 100% silk) dyed with an ethanol extract of Gardenia jasminoides (G. jasminoides). More specifically, these fabrics were dyed using a G. jasminoides extract with a dye bath ratio of 1:20 at 40–60 °C for 60 min, followed by post-mordanting. The concentrations of the aluminum sulfate, copper sulfate, and ferrous sulfate mordants were each set to 3% (o.w.f.). The samples were mordanted using a mordant bath ratio of 1:30 at 40 °C for 20 min. The iron mordant slightly increased the dye uptake (K/S) of the cotton fabric but did not increase the dye uptake (K/S) of the silk fabric. The antimicrobial efficacies of the dyed fabrics against methicillin-resistant Staphylococcus aureus (MRSA) ATCC 33591 were determined to be 99.8 and 87.8% for the cotton and silk fabrics, respectively. The inhibitory effects of the cotton and silk fabrics against MRSA were 30.5 × and 167.3 × the inoculum size, respectively, indicating the superior inhibitory effect of the dyed cotton fabric. These results suggest that the fabrics dyed with G. jasminoides extract may possess antibacterial activity against antimicrobial-resistant bacteria.