Biodegradation and enhancement of 2,4-dichlorophenol by marine halophilic Bacillus subtilis AAK
Aïda M. Farag, Asmaa Fawzy, Moustafa Y. El‐Naggar, Khaled M. Ghanem
Abstract
Chlorophenolic compounds (CPs) are highly persistent environmental pollutants and very toxic to living organisms. The present study focused on 2,4-dichlrophenol (2,4-DCP) degradation by a marine isolated Bacillus subtilis AAK (accession number MF037698). The optimum pH and temperature for 2,4-DCP degradation were 8.0 and 37 °C, respectively. The strain has the ability to degrade six diverse phenolic compounds. As well, the biodegrading ability of cells was enhanced by the addition of glucose (2%). The components and cultural conditions were screened using Plackett-Burman experimental design which indicated that 2,4-DCP, yeast extract, MgSO4·7H2O, KCl, inoculum size and volume of the medium were positively significantly influenced the biodegradation. Bacillus subtilis AAK can remediate 2,4-DCP in the presence of some metal ions (Cu2+, Co2+, Ni and Zn2+) at a concentration of 20 mg/l without reducing their degradation ability. Therefore, the bacterial strain B. subtilis AAK has a potential application for improving the bioremediation of wastewater containing 2,4-DCP in addition to other phenolic compounds and heavy metals.