Oral Presentation 25th Annual Lorne Proteomics Symposium 2020

The use of natural products in the leather industry: Depilation without damage. (#3)

Yi-Hsuan Tu 1 , Meekyung Ahn 1 2 , Mark L Patchett 1 , Rafea Naffa 2 , Dragana Gagic 1 , Jasna Rakonjac 1 , Gillian E Norris 1
  1. Massey University, Palmerston North, MANAWATU, New Zealand
  2. New Zealand Leather and Shoe Research Association, Palmerston North, Manawatu, New Zealand

The removal of hair from skin (depilate) is traditionally done by mechanical means, (shaving) or using chemicals.  Although chemicals are very effective, they can damage or burn the skin and the waste products are an environmental problem. More recently enzymes have been trialled, but these are difficult to control and also often damage the skin.


We have found a simple solution; a dairy by-product that results in easy depilation without apparent skin damage and have used a number of different analyses to compare the molecular components of our depilated skins with those depilated using chemicals.  Firstly SEM showed there was no obvious damage to skin depilated using the natural product and TEM showed the arrangement of collagen fibres was similar to those in skins depilated with chemicals.  To assess any less visible damage to the skins, quantitative biochemical analyses were carried out to measure any changes in amino acid composition, collagen crosslink composition and concentration, and glycosaminoglycan concentration and compared to the levels in chemically depilated skins. Label free quantitative proteomic analyses were then carried out on skin samples using gelLC MSMS to identify any differences in the skin proteomes of each sample, including any differences in glycosylation and hydroxylation of the collagen molecules.  In order to determine any enzyme activity that could be responsible for depilation, and any protein based compounds that might be responsible for the preservation of the skins during the process, the solutions used for depilation were first analysed by SDS PAGE, and the resulting bands also subjected to proteomic analysis. This presentation will describe the progress that has been made towards understanding the scientific rational of this depilation process and the differences in the protein components of skin before and after depilation using this new environmentally friendly method and compared to the differences seen before and after chemical depilation.