Vandana et al.

reported that yeast extract supported for the highest laccase activity from

Ganodermalucidum. Sivakumar et al.(2010) study reveals that yeast extract

supported the highest laccase activity of 0.18 U/ml. Nitrogen plays key role in

laccase production, while the organic nitrogen source gave high laccase yields.

Nitrogen plays key role in laccase production, the nature and the concentration of

Figure 5. Effect of nitrogen source (2%) on laccase activity

nitrogen in the culture medium for growing the organism are essential for laccase

production. Medium containing peptone showed the highest laccase activity as

enzymes are substrate specific. Peptone is the simplified source of protein and can

be readily uptake by the microorganism. It is asource of protein, amino acids for

microbial growth.

Partial Purification of laccases

Culture filtrate of Aspergillus nigerwas obtained from the medium. Partial

purification of laccase was carried by two method ammonium sulfate and dialysis.

The crude enzyme was precipitated by ammonium sulfate precipitation up to 70%

saturation with a total activity of 0.096 U/ml with 0.82 mg/ml of protein. After

ammonium sulfate precipitation, the final purification by dialysis the fraction

showed 0.068U/ml enzyme activity 0.55 mg/ml protein. As in present study,

similar laccase activity was reported by several workers (Abou-Mansour et al.

2009; Jhadav et al. 2009) and purification of laccase enzyme was done by using

ammonium sulfate and dialysis method.

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International Journal of Bioinformatics and Biological Sciences : v.2 n.3&4. Dec. 2014