ENZYMATIC DEHAIRING OF CATTLE HIDE WITH AN ALKALINE PROTEASE ISOLATED FROM ASPERGILLUS TAMARII

Authors: Marmer, William; ANANDAN, DAYANANDAN - VISITING SCIENTIST; Dudley, Robert

Submitted to: American Leather Chemists Association Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2006
Publication Date: 6/21/2006
Citation: Marmer, W.N., Anandan, D., Dudley, R.L. 2006. Enzymatic dehairing of cattle hide with an alkaline protease isolated from aspergillus tamarii [abstract]. American Leather Chemists Association Meeting. p. 14.

Interpretive Summary:

Technical Abstract: An alkaline protease isolated from Aspergillus tamarii shows promise as a dehairing agent for use in the tannery. Standard dehairing conditions established for the protease isolated from Streptomyces griseus proved to be unsatisfactory for the alkaline protease. We optimized the dehairing conditions and found that a pre-wash with sodium dodecyl sulfate (SDS; 0.2%) greatly facilitated the dehairing. SDS removes the sebaceous material from the hair pore and should facilitate penetration of the enzyme from the hair side of the hide. The alkaline protease cannot remove the fine (new) hairs from the hide unless it is assisted by small amounts of sulfide. Alternatively, a sharpening agent can be included in a relime step. We developed and applied a relime step using alkaline sodium percarbonate in place of the traditional sharpening agent, sodium sulfide/lime. A 4% NaOH/ 4% sodium percarbonate relime step (2 h) removed all of the hair, leaving a very clean, light colored hide. The use of a percarbonate relime step also reduced the amount of hazardous effluent leaving the tannery. We will present representative results from experiments on small hide panels-mechanical results, shrinkage temperatures and % Cr on resulting crust leather-and show that the results do not differ from those from leather prepared from sulfide-dehaired hide.