A kinetic model for surfactant inhibition of pentachlorophenol biodegradation

✍ Scribed by Todd L. Cort; Angela R. Bielefeldt

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 222 KB
• Volume: 78
• Category: Article
• ISSN: 0006-3592
• DOI: 10.1002/bit.10257

✦ Synopsis

Abstract

A kinetic model is used to describe the effect of the nonionic surfactant Tergitol NP‐10 (TNP10) on pentachlorophenol (PCP) biodegradation by Sphingomonas chlorophenolica sp. strain RA2. Different initial biomass to initial substrate ratios ranging from 13 to 418 were tested with 23 TNP10 concentrations ranging from 0 to 1500 mg/L. Tests were also conducted at 10°C and 20°C. No PCP biodegradation inhibition was observed at concentrations below the critical micelle concentration (CMC) of 50 mg/L. TNP10 concentrations above 100 to 200 mg/L were increasingly inhibitory to PCP biodegradation rates. This inhibition was best described by the Monod kinetic equation wherein the effect of TNP10 inhibition is reflected in the half‐saturation constant (K~s~). The value of the K~s~ increased from between 1.5 and 13.5 mg/L with no surfactant present to 44 to 131 mg/L at 1000 mg/L TNP10. Using a standard competitive inhibition approach, the inhibition constant for TNP10 was approximately 100 mg/L at both 10°C and 20°C. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 606–616, 2002.