Ligninolytic enzymes of endospore-forming Bacillus aryabhattai BA03

Abstract

In this work we investigated the enzymes produced by Bacillus aryabhattai BA03, particularly in those involved in ligninolytic activities such as laccases (Lac), lignin peroxidases (LiP) and Mn-dependent peroxidase (MnD-P). In this way, the maximal production of Lac (0.069±0.000 U/mL) was obtained at pH 9, and 37 ºC after 72 h. LiP expressed the highest activity at 96 h in acid medium at 37 ºC (0.741±0.029 U/mL). Meanwhile, the strain produced MnD-P (1.052±0.001 U/mL) at the highest temperature assayed (44 ºC) and pH 7 at 72 h. In addition, this microorganism produced resistant endospores able to germinate after the sterilization program (121 ºC, 15 min) showing a high enzymatic activity. Using the heat-treated culture as inoculum, the percentage of decolorization of 150 mg/L of Coomassie Brillant Blue reached 89.42±0.11% in only 24 h. These results open the use of these enzymes and endospores in bioremediation processes carried out under diferent temperatures and pH values