Statistical optimization of cultural variables for enzymatic degradation of aflatoxin B by Panus neostrigosus.

The aim of this study is to determine the best aflatoxin B degradation conditions which was optimized using a combination of the Plackett-Burman and Box-Behnken methods with Panus neostrigosus culture filtrate. Panus neostrigosus was grown in a modified Kirk Broth medium to determine optimal degradation conditions. As a result, aflatoxin B was degraded under varying culture conditions. The Plackett-Burman method was designed after sixteen different experiments with fifteen variables. The three most effective variables (Sucrose, yeast extract, wheat bran) were chosen for the Box-Behnken methodology. The aflatoxin B degradation rate was 49% in just 1 h exposure to culture filtrate which was obtained under optimal growth conditions; (g-ml/L) sucrose 10, yeast extract 3, wheat bran 3, soytone 5, KHPO 2, MgSO.7HO 0.5, CaCl.HO 0.1, ammonium tartrate 2, trace element solution 10; 28 °C of incubation temperature, medium pH 5, 7.5% inoculum rate, 125 rpm of agitation speed, and a twelve-day incubation period. The SDS-PAGE studies show that the enzyme responsible for AFB degradation has 38 kDa molecular weight and has no laccase or MnP activity. To the best of our knowledge, this is the first report for AFB degradation by Panus neostrigosus.