Biological treatment of chicken feather waste for improved biogas production
Artikel i vetenskaplig tidskrift, 2011

A two-stage system was developed which combines the biological degradation of keratin-rich waste with the production of biogas. Chicken feather waste was treated biologically with a recombinant Bacillus megaterium strain showing keratinase activity prior to biogas production. Chopped, autoclaved chicken feathers (4%, W/V) were completely degraded, resulting in a yellowish fermentation broth with a level of 0.51 mg/mL soluble proteins after 8 days of cultivation of the recombinant strain. During the subsequent anaerobic batch digestion experiments, methane production of 0.35 Nm(3)/kg dry feathers (i.e., 0.4 Nm(3)/kg volatile solids of feathers), corresponding to 80% of the theoretical value on proteins, was achieved from the feather hydrolyzates, independently of the pre-hydrolysis time period of 1, 2 or 8 days. Cultivation with a native keratinase producing strain, Bacillus licheniformis resulted in only 0.25 mg/mL soluble proteins in the feather hydrolyzate, which then was digested achieving a maximum accumulated methane production of 0.31 Nm(3)/kg dry feathers. Feather hydrolyzates treated with the wild type B. megaterium produced 0.21 Nm(3) CH(4)/kg dry feathers as maximum yield.

bacillus-megaterium

poultry slaughterhouse waste

feather waste

feed

keratin

Bacillus licheniformis

anaerobic-digestion

Bacillus megaterium

strains

proteases

gene expression

purification

potentials

keratinase

anaerobic digestion

Författare

Gergely Forgács

Chalmers, Kemi- och bioteknik, Kemisk reaktionsteknik

S. Alinezhad

Högskolan i Borås

A. Mirabdollah

Högskolan i Borås

E. Feuk-Lagerstedt

Högskolan i Borås

I. S. Horvath

Högskolan i Borås

Journal of Environmental Sciences

1001-0742 (ISSN)

Vol. 23 10 1747-1753

Ämneskategorier

Annan naturresursteknik

DOI

10.1016/S1001-0742(10)60648-1