Biodegradation of pyridine raffinate by two bacterial co-cultures of Bacillus cereus (DQ435020) and Alcaligenes faecalis (DQ435021)

This study deals with the optimization of bacterial degradation of pyridine raffinate by previously isolated two aerobic bacteria ITRCEM1 (Bacillus cereus) and ITRCEM2 (Alcaligens faecalis) with accession number DQ4335020 and DQ435021, respectively. The degradation of pyridine raffinate was studied by axenic and mixed bacterial consortium at different nutritional and environmental conditions after the removal of formaldehyde from pyridine raffinate (FPPR). Results revealed that the optimum degradation of pyridine raffinate was observed by mixed bacterial culture in presence of glucose (1% w/v) and peptone (0.2% w/v) at 20% FPPR, pH 7.0, temperature 30°C and 120 rpm at 168 h incubation period . The HPLC analysis of degraded pyridine raffinate samples has indicated the complete removal of α, β and γ picoline. Further, the GC–MS analysis of FPPR pyridine raffinate has shown the presence of pyrazine acetonitrile (6.74), 1,3-dioxepin (8.68), 2-pyridine carboxaldehyde (11.26), propiolactone (12.06), 2-butanol (13.10), benzenesulfonic acid (16.22) and 1,4-dimethyl pyperadine while phenol (17.64) and 3,4-dimethyl benzaldehyde as metabolic products of FPPR.