Strains of bacteria [Pseudomonas flurescens (Pf1 and Pf2); Bacillus subtilis (B)] were used for treatment of kraft bagasse pulp. Both of the bacterial treated kraft bagasse pulp (BKBP) and control (C) pulp samples were chelated with EDTA and then bleached with hydrogen peroxide. The effect of aging on paper brightness was investigated. The brightness change due to aging for both control sample and bleached bacterial treated (BBKBP) pulp are 19.38% and (5.99%-15.35%), respectively. The crystallinity index (CrI) is calculated for both control sample (C) and BBKBP via X-ray diffraction patterns. It was found that the CrI for BBKBP was increased by 4.46% compared with the control (C) sample. The relative intensity and assignment of absorption bands for BKBP) were studied via FTIR spectra. Pyrolytic behavior of the different samples was investigated by thermal gravimetric analysis and derivative thermogravimetric techniques. Calculations of the mass loss were used to elucidate the rate constant of decomposition and the activation energy. (c) 2007 Wiley Periodicals, Inc.