Optimization of Laccase production by klebsiella sp.: effect of nutrition factory on medium formulation

The present study was conducted to optimize the laccase production from bacteria using different nutrition sources. The laccase producer, identified as Klebsiella sp. was selected for the optimization of laccase production with particular attention to the effect of nutrition factors on laccase production using submerged culture technique. Laccase was characterized to assist in formulating the best condition for the bioconversion of lignin. This approach enables to optimize number of nutritional factor and calculate their interaction and combination of nutrition in the laccase production. Five nutrition sources selected were carbon sources, nitrogen organic sources, inorganic nitrogen, amino acid and metal ions. The other physical factor was maintained constant such as pH, temperature, inoculums size and incubation time. The best culture condition obtained consisted of beef extract (1.0 g), ammonium chloride (0.1 g), di-potassium phosphate (0.05 g), magnesium sulphate heptahydrate (0.03 g), magnesium chloride (0.1 g), Sodium Chloride (0.1 g), and starch (1.0 g). Under the above culture conditions, the time of fermentation carried out was 24 hours with maximum laccase activity of 9.099x 10‐⁶ (U/ml). The characterization study of concentrated laccase revealed the importance of an acidic condition for the highest laccase activity.