Production of catalase-peroxidase and continuous degradation of hydrogen peroxide by an immobilised alkalothermophilic bacillus sp.

Abstract

Catalase-peroxidase (CP) production by a Bacillus sp. (Bacillus KF) newly isolated from a textile finishing effluent and by this strain immobilised on light expanded clay was studied. In cultivations of Bacillus KF increased catalase activity (about 30-fold) was measured after the addition of H2O2 and Orange IV, while ascorbic acid, pyrogallol and Paraquat, seemed to be poor inducers. Catalases in the cell extract from Bacillus KF showed remarkable stability at high temperatures and pH values with half-lifes of 20 h at pH=9 and 60 °C while half-lifes based on the activity of catalases of only 2.2 h were measured in a column reactor during hydrogen peroxide degradation for the whole cells. However, after the addition of cultivation medium immobilised cells can be regenerated and thus used for textile bleaching effluent treatment.