Degradation of keratin and collagen containing wastes by newly isolated thermoactinomycetes or by alkaline hydrolysis

Abstract

The aim of this study was to develop a method for microbial degradation of indigenous keratin wastes and to compare it with a method of alkaline hydrolysis. Native sheep skin and wool were chosen as a model mixture of collagen and keratin wastes discarded by the leather and fur industries. Suitable conditions were found for hydrolysis of this mixture by four newly isolated thermoactinomycete strains. Another set of experiments was carried out using alkaline hydrolysis of keratin wastes. It was shown that microbial hydrolysates contained predominantly low molecular peptides and amino acids, including essential ones, while the alkaline hydrolysis produced predominantly peptides of higher molecular weight. A simple and a low-cost method was proposed for rapid and effective biodegradation of keratin wastes using Thermoactinomyces strains. The proposed method could find application in agriculture for preparing mixtures containing valuable peptides and amino acids.