Toxicity evaluation and biodegradation of phenanthrene by laccase from PBURU 12.

The newly isolated PBURU 12 demonstrated a high tolerance and potential for the degradation of phenanthrene. The fungal isolate was able to tolerate 100 ppm of phenanthrene with 45% relative growth. The crude laccase produced by PBURU 12 was able to degrade phenanthrene by up to 98% within 24 h. The degradation metabolites showed the absence of toxic compounds. Microbial viability tests using and revealed that the treated phenanthrene was less toxic than untreated phenanthrene. Phytotoxicity and genotoxicity tests, using and , indicated that the treated phenanthrene was less toxic to the plants. No mutagenic activity was found in the Ames test. The crude laccase from PBURU 12 was demonstrated as a potential tool for the biodegradation of PAHs (phenanthrene), with low toxic effects after the degradation.