A simplified dehydrogenase enzyme assay in contaminated sediment using 2-(p-Iodophenyl)-3(p-nitrophenyl)-5-phenyl tetrazolium chloride

J Microbiol Methods. 2003 Jun;53(3):411-5. doi: 10.1016/s0167-7012(02)00251-8.

Abstract

2-(p-Iodophenyl)-3(p-nitrophenyl)-5-phenyl tetrazolium chloride (INT) accepts electrons from dehydrogenase enzymes and is reduced to a red-colored formazan (INTF), which can be quantified by colorimetric analysis. Use of previously published methods for this technique was unsuccessful due to background chemical reactions from high levels of polycyclic aromatic hydrocarbons (PAHs) and metals in the sediments. A modified method using acetonitrile extraction of the INTF was efficient and did not chemically reduce INT. This activity method is simple, quick, inexpensive and precise.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerobiosis
  • Anaerobiosis
  • Bacteria / enzymology
  • Colorimetry / methods*
  • Geologic Sediments / microbiology
  • Indicators and Reagents
  • Oxidation-Reduction
  • Oxidoreductases / analysis*
  • Soil Microbiology*
  • Soil Pollutants* / metabolism
  • Temperature
  • Tetrazolium Salts / chemistry*
  • Water Microbiology

Substances

  • Indicators and Reagents
  • Soil Pollutants
  • Tetrazolium Salts
  • iodonitrotetrazolium
  • Oxidoreductases