Phenol degradation studies using microbial consortium isolated from environmental sources

A microbial consortium consisting of five phenol-degrading strains was developed. The consortium could degrade 99% of 1000 mg l−1 phenol after 72 h incubation with a biomass increase of 2.6 × 107 to 4 × 1012 CFU ml−1. Characterization of the members revealed that consortium consisted of Candida tropicalis (1.2 × 105 CFU ml−1), Aspergillus fumigatus (1.1 × 105 CFU ml−1), Candida albicans (3.0 × 103 CFU ml−1), Candida haemulonis (2.6 × 103 CFU ml−1) and Streptomyces alboflavus (1.1 × 105 CFU ml−1). Performance of consortium was accessed by specific growth rate (μ) and yield coefficient (Yx/s). The consortium exhibited activity of phenol hydroxylase and catechol 1,2-dioxygenase suggesting that members in consortium followed ortho pathway for phenol degradation. Response surface methodology (RSM) has been adopted to evaluate the effect of different parameter such as initial phenol concentration, temperature, pH and time on phenol degradation. The maximum percentage of phenol degradation is observed at optimized value of process variables such as initial concentration 1000 mg l−1, temperature 35 °C, pH 7 and incubation time of 96 h.