Biodegradation

, Volume 21, Issue 4, pp 645–657

Statistical medium optimization and biodegradative capacity of Ralstonia eutropha toward p-nitrophenol

  • Zeinab Salehi
  • Farzaneh Vahabzadeh
  • Morteza Sohrabi
  • Shohreh Fatemi
  • Hussein Tawfiq Znad
Original Paper

DOI: 10.1007/s10532-010-9332-5

Cite this article as:
Salehi, Z., Vahabzadeh, F., Sohrabi, M. et al. Biodegradation (2010) 21: 645. doi:10.1007/s10532-010-9332-5

Abstract

The effect of p-nitrophenol (PNP) concentration with or without glucose and yeast extract on the growth and biodegradative capacity of Ralstonia eutropha was examined. The chemical constituents of the culture medium were modeled using a response surface methodology. The experiments were performed according to the central composite design arrangement considering PNP, glucose and yeast extract as the selected variables whose influences on the degradation was evaluated (shaking in reciprocal mode, temperature of 30°C, pH 7 and test time of about 9 h). Quadratic polynomial regression equations were used to quantitatively explain variations between and within the models (responses: the biodegradation capacity and the biomass formation). The coefficient of determination was high (Radjusted2 = 0.9783), indicating the constructed polynomial model for PNP biodegradative capacity explains the variation between the regressors fairly well. A PNP removal efficiency of 74.5% occurred within 9 h (15 mg/L as the initial concentration of PNP with use of yeast extract at 0.5 g/L).

Keywords

Ralstonia eutrophaBiodegradationp-nitrophenolCentral composite designYeast extractGlucose

Abbreviations

PNP

p-nitrophenol

LC

Liquid culture

RSM

Response surface methodology

CCD

Central composite design

NAs

Nitroaromatics

NADPH

Nicotinamide adenine dinucleotide phosphate

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Zeinab Salehi
    • 1
    • 2
  • Farzaneh Vahabzadeh
    • 1
  • Morteza Sohrabi
    • 1
  • Shohreh Fatemi
    • 3
  • Hussein Tawfiq Znad
    • 2
  1. 1.Chemical Engineering DepartmentAmirkabir University of TechnologyTehranIran
  2. 2.Research Center for Biochemical and Environmental EngineeringToyo UniversityKawagoeJapan
  3. 3.Chemical Engineering DepartmentUniversity of TehranTehranIran