Biodegradation and detoxification of phenanthrene in in-vitro and in-vivo conditions by a newly isolated ligninolytic fungus Coriolopsis byrsina strain APC5 and characterization of their metabolites for environmental safety

Abstract

\n Polycyclic aromatic hydrocarbons (PAHs) are recalcitrant organic pollutants generated from agricultural, industrial, and municipal sources, and their strong toxic, carcinogenic and teratogenic properties pose a harmful threat to human beings. The present study delas with the bioremediation of phenanthrene by a ligninolytic fungus, Coriolopsis byrsina strain APC5, isolated from the fruiting body of decayed wood surface. During the experiment, Coriolopsis byrsina strain APC5 was found as a promising organisms for the degradation and detoxification of phenanthrene (PHE) in in-vitro and in-vivo conditions. HPLC analysis showed that the C. byrsina strain degraded 99.90% of 20 mg/L PHE in in-vitro condition wheras 77.48% degradation of 50 mg/L PHE was reported in in-vivo condition. The maximum degradation of PHE was noted at pH 6.0 at 25 ºC temperature under shaking flask conditions. Further GC-MS analysis of fungal treated samples showed detection of 9, 10-Dihydroxy phenanthrene, 2, 2-Diphenic acid, phthalic acid, 4-heptyloxy phenol, benzene octyl and acetic acid anhydride as a metabolic products of degraded PHE. Furthermore, the phytotoxicity evaluation of degraded PHE was observed through the seed germination method using Vigna radiata and Cicer arietinum seeds. The phytotoxicity results showed that the seed germination index and vegetative growth parameters of plants were increased in the degraded PHE soil. As a result, C. byrsina strain APC5 was found to be a potential organism for the degradation and detoxification of PHE without showing any adverse effect of their metabolites.