COMPARISON OF PHENANTHRENE AND PYRENE DEGRADATION BY DIFFERENT WOOD-DECAYING FUNGI

The degradation of phenanthrene and pyrene was investigated by using f ive different wood-decaying fungi, After 63 days of incubation in liqu id culture, 13.8 and 4.3% of the [ring U-C-14] phenanthrene and 2.4 an d 1.4% of the [4,5,9,10-C-14] pyrene were mineralized by Trametes vers icolor and Kuehneromyces mutabilis, respectively, No (CO2)-C-14 evolut ion was detected in either [C-14]phenanthrene or [C-14]pyrene liquid c ultures of Flammulina velutipes, Laetiporus sulphureus, and Agrocybe a egerita, Cultivation in straw cultures demonstrated that, in addition to T. versicolor (15.5%) and K. mutabilis (5.0%), L, sulphureus (10.7% ) and A. aegerita (3.7%) were also capable of mineralizing phenanthren e in a period of 63 days, Additionally, K. mutabilis (6.7%), L. sulphu reus (4.3%), and A. aegerita (3.3%) mineralized [C-14]pyrene in straw cultures, The highest mineralization of [C-14] pyrene was detected in straw cultures of T. versicolor (34.1%), which suggested that minerali zation of both compounds by fungi may be independent of the number of aromatic rings. Phenanthrene and pyrene metabolites were purified by h igh-performance liquid chromatography and identified by UV absorption, mass, and H-1 nuclear magnetic resonance spectrometry, Fungi capable of mineralizing phenanthrene and pyrene in liquid culture produced enr iched metabolites substituted in the K region (C-9,10 position of phen anthrene and C4,5 position of pyrene), whereas all other fungi investi gated produced metabolites substituted in the C-1,2, C-3,4, and C-9,10 positions of phenanthrene and the C-l position of pyrene.