Biocidal Activity of Selected Preparations for Leather Protection

Abstract

This research work involved the selection of biocides for the antimicrobial treatment of leathers. The scope of the research work covered microbiological tests of leather samples tanned utilising the same technology, with microbiological treatment made using 9 different preparations, as well as a test of leather without biostabilisation. Commercial biocides taken for inwestigation were as follows: NS 500 – an aqueous solution of nanosilver 500 ppm, ODH – tea tree oil, and OP – orange oil. Preparations prepared by diluting the purchased products were as follows: S27-22 – an aqueous solution containing silver chloride and titanium dioxide, SH 22-27 – an aqueous solution containing zinc pyrithione, ST 99-19 – an aqueous solution containing dimethyltetradecyl [3-(trimethoxysilyl)propyl]ammonium chloride, SU – an aqueous solution containing polyhexamethylene biguanide, and SGP – a saturated solution of aluminum potassium sulfate. Also a preparation was made by combining NS 500 M250 – 500 ppm nanosilver solution and a 250 ppm copper colloid. Evaluation of the effectiveness of biostabilisation of the leather samples and antimicrobial activity of the preparations used was carried out. Staphylococcus aureus and Escherichia coli bacteria and Candida albicans, Aspergillus brasiliensis and Trichophyton mentagrophytes fungi were used in the study. The assessment of microbial growth on samples was carried out according to Polish standards. Assessment of the resistance to bacteria and C. albicans yeast was made according to the PN-EN ISO 20645: 2006 standard – a method of diffusion on an agar plate. Assessment of the resistance to A. brasiliensis and T. mentagrophytes fungi was made according to the PN-EN ISO 14119: 2005 standard. Among the tested preparations to protect leathers against the effects of microorganisms, overall efficacy was obtained for SH 22-27, NS 500 M 250, SU and ODH.