In order to evaluate tbe keratinolytic activity of saprophytic microfungi the following values were determined, the percentage keratin substrate decomposition (native feathers). the changes of pH of medium the liberation of peptidic substances in this process, as well as the liberation of amine nitrogen and cystein. The presence of keratinase was examined in culture filtrates and the proteolytic activity in the presence of casein. It was noted that among the above mentioned indices the percentage decrease of substrate mass was the most useful criterion of keratinolytic activity evaluation.
Korniłłowicz, T. (2014). Methods for determining keratinolytic activity of saprophytic fungi. Acta Mycologica, 29(2), 169–178. https://doi.org/10.5586/am.1994.017