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=Biotechnology and Bioprocess Engineering 2007, 12: 410-416 jáÅêçÄá~ä=aÉÖê~Ç~íáçå=çÑ=mçäóÅóÅäáÅ=^êçã~íáÅ=eóÇêçÅ~êÄçåë=áå=pçáä=Äó=_~ÅíÉêáìãJcìåÖìë=`çJÅìäíìêÉë==gÉçåÖJaçåÖ=háã=~åÇ=`ÜçìäJdóìå=iÉÉG=Institute of Industrial Biotechnology, Department of Biological Engineering, Inha University, Incheon 402-751, Korea = ^Äëíê~Åí= Two fungi and the phenanthrene-degrading bacterial strain oÜçÇçÅçÅÅìë sp. IC10 were used as inocula for the bio-remediation of petroleum hydrocarbon-contaminated soil from a manufactured gas plant area. The two fungi, which were previously isolated from different hydrocarbon-contaminated soil samples, were identified as ^ëéÉêÖáääìë=íÉêêÉìë and mÉåáÅáääáìã sp. In addition, two types of co-cultures which consist of fungal species including ^K=íÉêêÉìë or mÉåáÅáäJäáìã sp. with oÜçÇçÅçÅÅìë sp. IC10 were applied. After a 10-week incubation period, the concentrations of anthra-cene, phenanthrene, and pyrene were totally biodegraded by days 68, 54, and 64, for the 16 polycyclic aromatic hy-drocarbons (PAH’s) tested. The ecotoxicity of the soil after bioremediation did not show any effect on the survival of a~éÜåá~=ã~Öå~ (24 h-old-daphnids). However, the toxicity on seed germination of _ê~ëëáÅ~=~äÄ~ and the oxidoreduc-tase activity of _~Åáääìë=ÅÉêÉìë declined after 5- and 10-weeks of incubation, respectively. Co-cultures of mÉåáÅáääáìã sp. and oÜçÇçÅçÅÅìë sp. IC10 revealed the best efficiency at reducing ecotoxicity. © KSBB hÉóïçêÇëW=ÄáçêÉãÉÇá~íáçåI=mêI Rhodococcus, Penicillium=====fkqolar`qflk= Polycyclic aromatic hydrocarbons (PAH’s) represent a large group of organic pollutants which have contaminated the environment through the improper disposal of materials such as creosote, coal tar, and hydrocarbon fuels [1-3]. PAH’s are ubiquitous pollutants found in soil at wood pres-ervation plants, gas works, oil refineries, runoff from asphalt pavements, and combustion processes. Their physicochemi-cal properties, which include low water solubility and high adsorption coefficient, make soils and sediments environ-mental sinkers of PAH’s. PAH’s represent a considerable environmental concern [4,5] because they are genotoxic and carcinogenic. Their mutagenicity varies with the number of aromatic rings and the PAH’s released into the environment could be removed by many processes including volatiliza-tion, photo-oxidation, chemical oxidation, bioaccumulation, and adsorption on soil particles. However, the most success-ful process for removal and elimination of PAH’s from the environment is to use the microbial transformation and deg-radation [6,7]. G`çêêÉëéçåÇáåÖ=~ìíÜçê Tel: +82-32-860-7518 Fax: +82-32-872-4046 e-mail: leecg@inha.ac.kr In PAH contaminated soil, the microorganisms capable of degrading and utilizing hydrocarbons would be present and could be employed for PAH elimination [8]. Potential bio-degradation microorganisms isolated from hydrocarbon-contaminated environments have been found as active as or even more active than those originating from uncontami-nated soil, since certain bacteria could acclimate themselves to the contaminated environments [9,10]. Some different bacterial genera, including species of Pseudomonas, Alcali-genes, Mycobacterium, Rhodococcus, Burkholderia [1,11-13], and Cycloclasticus [14,15], are able to degrade PAH’s. For the bacterial isolates, the majority have enriched their ability to grow on low molecular weight PAH’s (2- or 3-ring PAH’s). Nevertheless, some studies have shown that some bacteria such as Mycobacterium, Rhodococcus, Alcaligenes, Pseudomonas, and Sphingomonas can grow on the four-ring PAH’s [16-19]. Moreover, several other lower molecular weight PAH’s (LMW-PAH’s) facilitate the degradation of higher molecular weight PAH’s (HMW-PAH’s) when lower and higher molecular weight PAH’s were co-metabolized [1,14,15,20]. For fungi, the white rot fungi are able to de-grade PAH’s [21] and other aromatic compounds through peroxide enzymes [20,22,23]. Several fungal species have also been found to degrade PAH’s of both low and high mo-lecular weight [1].