Pentachlorophenol dechlorination and simultaneous Cr reduction by Pseudomonas putida SKg-1 MTCC (10510): characterization of PCP dechlorination products, bacterial structure, and functional groups

摘要

It is the first report in which a novel psychrotro-phic Pseudomonas putida SKg~(-1) strain was evaluated for simultaneous bioremediation of pentachlorophenol and Cr~(6+) under various cultural and nutritional conditions. Pentachlorophenol (PCP) dechlorination products, bacterial structure, and functional groups were characterized by gas chromatography and mass spectrometry (GC-MS), scanning electron microscope and energy dispersive X-ray spectroscopy (SEM-EDS), and Fourier-transform infrared (FTIR) techniques. The strain was extremely tolerant to excessively higher individual concentration of PCP (1,400 mg l~(-1)) and Cr~(6+) (4,300 mg l~(-1)). Increasing concentration of PCP and Cr~(6+) exerted inhibitory effect on bacterial growth and toxicants' removal. The strain exhibited growth, and concomitantly remediated both the pollutants simultaneously over a broad pH (7.0-9.0) and temperature (28-32 °C) range; maximum growth, PCP dechlorination (87.5 %), and Cr~(6+) removal (80.0 %) occurred at optimum pH 8.0 and 30 °C (from initial PCP 100 mg l~(-1) and Cr~(6+) 500 mg l~(-1)) under shaking (150 rpm) within 72 h incubation.