Biodegradation of malathion and evaluation of kinetic parameters using three bacterial species

Efficacy of three different bacterial species for biodegradation of malathion and its secondary products have been investigated. The concentration range of malathion under investigation was 25-200 mg·L−1. It has been observed that Pseudomonas putida was found to be most efficient for degradation of malathion. The removal of malathion was 72% at its concentration of 125 mg·L−1. The optimum parameters were studied for all three bacterial species in batch mode. The average values of Ks and μmax were obtained for all these species for degradation of malathion. Results indicate that P. putida has high degradation potential than Rhodoccocus rhodochrous and Sphingomonas sp. The degradation of P. putida was maximum at concentration of 125 mg·L−1, pH and temperature at 7 ± 0.2, 80 °C respectively. Metabolites were obtained using GCMS analysis. © 2016 Tomsk Polytechnic University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license

Removal of aqueous benzene in the immobilized batch and continuous packed bed bioreactor by isolated Bacillus sp. M1

Benzene biodegradation was studied in batch and continuous packed bed bioreactors using polyurethane foam (PUF) as packing media by isolated Bacillus sp. M1. The values of optimized process parameters were found to be 800 × 106CFU·mL−1, 400 mg·L−1, 7.0 and 37 °C for inoculum size, substrate concentration, pH and temperature respectively. Continuous packed bed bioreactor (CPBBR) was operated and monitored for 69 days on laboratory scale at various flow rates (10-60 mL·h−1). The steady state removal efficiency was observed more than 90% up to the inlet load of 288 mg·L−1.d−1 and elimination capacity was found to be 91.2-266.4 mg·L−1·day−1. Monod growth model was applied for the removal of benzene and values were found to be (Ks: 215.07 mg·L−1; μmax: 0.314 day−1)

Biodegradation of reactive orange 16 (RO-16) dye in packed bed bioreactor using seeds of Ashoka and Casuarina as packing medium

216-221The main objective of this work was to evaluate the performance of Ashoka and Casuarina (abundantly available in India as agrowaste) seeds as packing material with immobilized mixed culture of microorganisms for biodegradation of reactive orange dye (RO-16) in the continuous packed bed bioreactor. The percent removal of RO-16 was increased with time in both cases and attained constant value on the 10th d of operation with maximum removal 63.5±5% and 69.27±5%, respectively for Ashoka and Casuarina seeds, at inlet flow rate of 1.0 LPH and initial concentration of 500 ppm. The second order of kinetics applied and it fitted well for both packing materials. The results demonstrate that the selected seeds have potential as to be used as packing material for biodegradation application in bioreactors