REDUCTION OF METHYLENE-BLUE BY BACILLUS SP

Methylene Blue (MB) was specifically decolorized by growing cells of B acillus subtilis IFO 13719, B. pumilus IFO 12092, B. licheniformis IFO 12200 and B. circulans IFO 13626, although it was not decolorized by B. subtilis IFO 3022. A reaction product of MB was identified as leuco MB by TLC. The product was ultimately oxidized by air since it was no t further metabolized by B. licheniformis IFO 12200. MB was reduced by the growing cells and the cell homogenates of Bacillus sp., but it wa s not reduced by the washed cells. Consequently, it was suggested that the reduction of MB depends upon the structure and physiological cond ition of bacterial cell envelope.