Feather Biodegradation For Feather Protein Lysate/ Feather Meal Mutual Formations: Optimization Using Crude YNDH Protease/Keratinase; Enzyme Partial Purification and Characterization

Abstract

Incubation parameters used for the production of a protein lysate from enzymatically degraded waste feather using crude keratinase produced by laceyella sacchari YNDH was optimized using RSM, amino acids quantification was estimated as well. The optimization resulted in total soluble protein 2089.5µg/ml. The optimal conditions were, time 20.2h, feather concentration 3g% and keratinase activity 24.5U/100ml at pH, 10; and cultivation temperature 50oC. The FPL was found enriched with essential and rare amino acids.In parallel, this YNDH enzyme group had been partially purified and some characteristics of it were studied. Crude enzymes were first concentrated with Amicon Ultra 10k centrifugal filter, and then concentrated proteins were applied to "QFF" strong anion column chromatography. The partially purified enzyme has an estimated molecular masses ranged 6 to 10 kDa. The maximum enzyme activity was observed at 70°C and pH 10.4 when measured by both casein and keratin azure as substrates. Interestingly, keratinolytic activity of this group was not affect by EDTA, PMSF and DTT. Generally the overall characters of this group protease/keratinase nearly the same when its activity was measured with both substrates suggesting that all these 3 protein bands working together as a group of keratinases.