Hyper Thermostable Laccase from Sub Optimally Grown Bacillus Cells with Dye Decolorization Property

Abstract

Laccase from a thermophilic Bacillus species produced sub-optimally at 37 oC in 24 h showed 55.4 % drop in activity with 5 min initial heating at 100 oC followed by 3 fold activity stimulation in 10 min and remained active till 25 min with continuous heating. However, the enzyme produced optimally at 45 oC was completely inactivated in 15 min under similar conditions. The enzyme was produced optimally on 4 % (w/v) wheat bran medium with two pH values of 3.0 and 7.0 at 45 oC in 72 h. The Km value with syringaldazine was found to be 0.22 mM. The immobilized enzyme could decolorize Indigo Carmine dye upto 70 % in 96 h.