Eco-friendly enzymatic dehairing of skins and hides by C. brefeldianus protease

摘要

Alkaline protease from Conidiobolus brefeldianus was efficient in unhairing various types of skins and hides. The crude protease preparation was active toward keratin-azure, elastin-orcin, azocasein, and azocoll, but did not show true collagenase activity. In addition, the crude enzyme exhibited other enzyme activities such as chon-droitinase, laminarase, and chitinase. Complete hair removal of skin/hide by the protease achieved in 16-18 h. The dehaired pelt showed smooth and white appearance due to hair removal along with epidermal layer. In addition, the grain was clean and without damage in enzymatically dehaired pelts. The microscopic observation of the cross-section of dehaired goat skin and cow hide showed absence of epidermis, hair shaft with empty follicles. Enzymatic dehairing resulted in complete and uniform fiber opening in the dermis and corium region. Physical properties viz. tensile strength, elongation, and tear strength of dyed crust of enzymatically and conventionally dehaired pelts were comparable. Results were also validated on large scale with goat skins and cow hides.