Enhancement of pyrene mineralization in soil by wood-decaying fungi

Abstract

The mineralization of [14C]pyrene in sterilized and non‐sterile soil was investigated using the wood‐decaying fungi Kuehneromyces mutabilis and Agrocybe aegerita in a period of 63 days. In sterilized soil 5.1% and 1.5% of the pyrene was mineralized to 14CO2 by K. mutabilis and by A. aegerita, respectively. In non‐sterile soil, 27.3% of pyrene was mineralized by indigenous soil microflora including a Mycobacterium gilvum strain. During soil inoculation with fungi the mineralization was higher (47.7% for K. mutabilis and 38.5% for A. aegerita). For a mass balance analysis the soil was extracted with toluene and methanolic KOH (humic acid extraction). Considering the sum of mineralization and formation of bound residues (non‐extractable radioactivity), about 50% (sterilized soil) and 75% (non‐sterile soil) of pyrene were eliminated by K. mutabilis. In comparison with indigenous soil microflora, K. mutabilis enhanced pyrene elimination up to 42%.

Biodegradation of polycyclic aromatic hydrocarbons by a thermotolerant white rot fungus <i>Trametes polyzona</i> RYNF13

“…The study of the PAH biodegradation of white rot fungi is valuable, not only from the standpoint of comparative biology, but also the expectation of finding more efficient PAH degraders for uses in bioremediation. The mineralization of PAHs in contaminated soils inoculated with PAH-degrading white rot fungi was found to be significantly higher than the results using the indigenous microorganism communities (Daniel et al, 1994;Sack and Fritsche, 1997). Nevertheless, PAH degradation by white rot fungi is typically affected by environmental factors, including temperature, pH, nutrients, oxygen, and bioavailability (Eibes et al, 2005;Galhaup and Haltrich, 2001;Hwang et al, 2007;Ryan et al, 2007).…”

Effect of Crude Oil Polluted Soil and Substrate Quantity on Some Morphological Characters of Pleurotus ostreatus (Jacq.) P. Kumm and Pleurotus pulmonarius (Fries) Quel Fruit Bodies

“…Therefore, in a highly polluted environment, large quantity (layer) of substrate is needed to reduce the effect of the pollutant. This now brings solution to the problems observed by Eggen and Vaclav [21] stating that one of the factors influencing the effectiveness of fungal soil remediation is the concentration of the pollutant.…”

“…During fruit body production (i.e., reproductive) stage of mushrooms, oxygen is required for effective fruitification and development of the cap and the stipe [23,24]. This could be the major reasons why increase in crude oil hindered the Morphological development of both fruit bodies [3,21,25] Increase in crude oil pollution also caused a reduction in the fresh weight of fruit bodies of the two oyster mushroom species (Table 3), there was no significant different in the fresh fruit body weight of both mushrooms at various levels of crude oil pollution p<0.05. This observed reduction in fruit body weight with attendant increase in crude oil pollution is synonymous with the decrease in cap diameter and stipe length of the fruit bodies of both mushroom species.…”

“…This could be as a result of certain inherent or genetic factors in the mushroom which gives it a more cellulose degrading ability due to secretion of certain enzymes like cellulose, lignase, peroxidise etc. [19][20][21]. Stipe length of the two mushrooms was also evaluated ( Table 2).…”

Aerobic Degradation by Microorganisms

“…Laboratory experiments have shown that the degradation of certain organopollutants (i.e., PAHs, PCP,TNT) is stimulated by wood-inhabiting white-rot fungi in contaminated soils (Phanerochaete chrysosporium, Lentinus edodes, Kuehneromyces rnutabilis; SACK and FRITSCHE, 1997;RAJARATH-NAM et al, 1998). However, a disadvantage of these fungi is their small competitive potential in soil.…”