Degradation of Toxic Compounds at Low and Medium Temperature Conditions Using Isolated Fungus

In the present study, a fungal strain isolated from the Antarctic soil was identified as Penicillium sp. CHY-2 based on its 5.8S rRNA gene sequence analysis. Furthermore, its biodegradation ability towards 13 different toxic compounds such as 4-butylphenol (4-BP), 4-sec-butylphenol (4-s-BP), 4-tert-butylphenol (4-t-BP), 4-nonylphenol (4-NP), 4-tertoctylphenol (4-t-OP), 4-chlorophenol (4-CP), phenol, bisphenol A (BPA), benzene, toluene, xylene, naphthalene, and phenanthrene at low (4 degrees C) and medium (15 degrees C) temperature conditions was evaluated using high pressure liquid chromatography. Among the 13 compounds, the strain CHY-2 effectively degraded the six compounds i.e., 4-BP, 4-s-BP, 4-t-BP, 4-NP, 4-CP, and phenol at 15 degrees C within one week, and at 4 degrees C within 3weeks. Also CHY-2 effectively degraded the 4-t-OP at 15 degrees C (70%), but not at 4 degrees C (35%). Among different carbon sources tested, glucose was found to be the most suitable and the growth of CHY-2 at 4 degrees C was slower than at 15 degrees C. Addition of Tween 80 increased the growth and degradation ability of CHY-2 towards 4-BP at 4 and 15 degrees C. The metabolites produced during the degradation of 4-BP were identified by gas chromatography-mass spectrometry. Also, bacteria present in the Antarctic soil were determined by denaturing gradient gel electrophoresis and the result showed the presence of Pseudomonas and Syntrophus groups of bacteria.