Utilization of keratin-containing biowaste to produce biohydrogen.
A two-stage fermentation system was constructed to test and demonstrate the feasibility of biohydrogen generation from keratin-rich biowaste. We isolated a novel aerobic Bacillus strain (Bacillus licheniformis KK1) that displays outstanding keratinolytic activity. The isolated strain was employed to convert keratin-containing biowaste into a fermentation product that is rich in amino acids and peptides. The process was optimized for the second fermentation step, in which the product of keratin fermentation--supplemented with essential minerals--was metabolized by Thermococcus litoralis, an anaerobic hyperthermophilic archaeon. T. litoralis grew on the keratin hydrolysate and produced hydrogen gas as a physiological fermentation byproduct. Hyperthermophilic cells utilized the keratin hydrolysate in a similar way as their standard nutrient, i.e., bacto-peptone. The generalization of the findings to protein-rich waste treatment and production of biohydrogen is discussed and possible means of further improvements are listed.
Bálint
Balázs
B
Department of Biotechnology, University of Szeged, Temesvári krt. 62, 6726 Szeged, Hungary.
Bagi
Zoltán
Z
Tóth
András
A
Rákhely
Gábor
G
Perei
Katalin
K
Kovács
Kornél L
KL
D000332:Aerobiosis; D000693:Anaerobiosis; D000818:Animals; D001407:Bacillus / Q000254:growth & development / Q000378:metabolism*; D001674:Bioelectric Energy Sources; D003470:Culture Media; D005241:Feathers / Q000737:chemistry / Q000378:metabolism; D005285:Fermentation; D005525:Food-Processing Industry; D006859:Hydrogen / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods; D007220:Industrial Waste; D007633:Keratins / Q000378:metabolism*; D019712:Thermococcus / Q000254:growth & development / Q000378:metabolism*
D003470:Culture Media; D007220:Industrial Waste; D007633:Keratins; D006859:Hydrogen