Pentachlorophenol Mineralization by Phanerochaete chrysosporium in Liquid Culture in the Presence of Syringic Acid or Humic Acid

Abstract

ABSTRACT

The influence of soil organic matter on PCP degradation was studied using the white rot fungus Phanerochaete chrysosporium in shake cultures contaiing syringic and humic acids. Cumulative ¹⁴CO₂ production after 31 days showed that the presence of syringic and humic acids at 1,000 mg/L significantly decreased PCP mineralization (P = 0.05). At a lower concentration of 250 mg/L, these acids did not significantly decrease mineralization compared with controls. Time series of ¹⁴CO₂ production showed that the presence of the acids, especially syringic acid, delayed the onset of mineralization and suppressed the maximum mineralization rate, but extended the lifetime of the mineralization reaction over that of the control. The presence of syringic acid at 1,000 mg/L significantly increased volatilization and partitioning of ¹⁴C onto the fungus at the end of 31 days, while an equal amount of humic acid significantly decreased the extent of mineralization and increased partitioning of ¹⁴C onto the fungus. The presence of 250 mg/L of each acid did not significantly affect the distribution. These results are evaluated and implications for practical remediation of PCP-contaminated soils are discussed.