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Aims: 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. Methods and Results: 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. Conclusion: A simple and a low-cost method was proposed for rapid and effective biodegradation of keratin wastes using Thermoactinomyces strains. Significance and Impact of the Study: The proposed method could find application in agriculture for preparing mixtures containing valuable peptides and amino acids.

Polyphenols, phenolic acids, fibres and antioxidant capacity were determined in water, acetone and methanol extracts of buckwheat, rice, soybean, quinoa and 3 amaranth cultivars. Their antioxidant activities were comparatively assessed by total radical-trapping antioxidative potential (TRAP), ferric ion-reducing antioxidant power (FRAP), cupric-reducing antioxidant capacity (CUPRAC) and nitric oxide (NO • ) assays, which comprised of contributions from polyphenols and phenolic acids (especially from the most abundant ferulic acid). The correlation coefficients between polyphenols and antioxidant activities of cereal and pseudocereal methanol extracts with FRAP, NO • , CUPRAC and TRAP were 0.99, 0.97, 0.96 and 0.77, respectively. The weakest correlation was with dietary fibres, an average one exhibited with tannins and marked correlation was shown with the phenolics. All the applied methods have shown that pseudocereals have higher antioxidant activity than some cereals (rice and buckwheat) and can be successfully replaced by cereals in case of allergy.