Applied Microbiology and Biotechnology

, Volume 74, Issue 6, pp 1368–1375

Humic acid effect on pyrene degradation: finding an optimal range for pyrene solubility and mineralization enhancement

  • Yanna Liang
  • David W. Britt
  • Joan E. McLean
  • Darwin L. Sorensen
  • Ronald C. Sims
Environmental biotechnology

DOI: 10.1007/s00253-006-0769-8

Cite this article as:
Liang, Y., Britt, D.W., McLean, J.E. et al. Appl Microbiol Biotechnol (2007) 74: 1368. doi:10.1007/s00253-006-0769-8

Abstract

The addition of humic acid (HA) to polycyclic aromatic hydrocarbon (PAH) contaminated systems has been shown to enhance, inhibit, or have no effect on the biodegradation of these PAHs. In this study, the surfactant effects of Elliott soil HA (ESHA) at two pH values were tested. At pH 7.0, ESHA did not behave as a surfactant. At pH 11.8, ESHA acted as a surfactant, as displayed by a decrease in surface tension with increasing concentrations of ESHA. The effect of ESHA on pyrene solubility was tested by adding 0 to 800 μg ESHA/g soil to soil-slurries. Enhancement of pyrene apparent solubility demonstrated a dose- and time-related effect. Broader doses from 0 to 10,080 μg ESHA/g soil and three higher doses from 3,360 to 10,080 μg ESHA/g soil were tested for their effects on pyrene mineralization by indigenous soil microorganisms and a novel PAH-degrading Mycobacterium sp. KMS in soil microcosms, respectively. ESHA amendments between 20 and 200 μg ESHA/g soil were found to consistently increase pyrene mineralization by indigenous microorganisms, while the 10,080 μg ESHA/g soil produced inhibition and all other doses presented no effects. Pyrene degradation by M. KMS was significantly inhibited by the addition of the highest dose of ESHA.

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Yanna Liang
    • 1
  • David W. Britt
    • 2
  • Joan E. McLean
    • 1
    • 2
  • Darwin L. Sorensen
    • 1
    • 2
  • Ronald C. Sims
    • 2
  1. 1.Utah Water Research LaboratoryUtah State UniversityLoganUSA
  2. 2.Department of Biological and Irrigation EngineeringUtah State UniversityLoganUSA