Novel keratinase from Trichoderma harzianum MH-20 exhibiting remarkable dehairing capabilities

The production of protease blend preparations containing keratinase, collagenase, alkaline, neutral and acidic proteases was investigated employing five fungal and one bacterial isolates grown on chicken feathers waste as protein-rich substrate, intending for suitable application in hide unhairing. Of the fungal isolates tested, Trichoderma harzianum MH-20 proved to be the most potent and produced distinct protease blend after 7 days in shaken cultures. This preparation included mainly active constitutive α-keratinase and low collagenase level. Other minor protease activities (alkaline, neutral and acidic) proteases were also detected. The operational blend properties suggest potential uses of this enzyme preparation in many industrial applications, particularly the hide unhairing process without any lime and sulphide addition. All the analytical measurements and microscopical observations on the enzymatic unheared skins by this fungal preparation in comparison with the lime-sulphide treated skin are reported and discussed.

► Six microbial isolates were screened for keratinase and protease production.
► Trichoderma harzianum MH-20 was the most potent keratinase and protease producer.
► The fungal enzyme preparation included active α-keratinase and low collagenase levels.
► Other protease (alkaline, neutral and acidic) activities were estimated.
► The fungal protease blend preparation exhibited remarkable dehairing capabilities.