Mineralization of phenanthrene by a Mycobacterium sp

Guérin, William; Jones, Galen E.

doi:10.1128/aem.54.4.937-944.1988

Cited by 180 publications

(77 citation statements)

References 42 publications

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“…A number of investigators have demonstrated that surfactants can enhance bioavailability of PAHs by increasing rates of their mass transfer (e.g., dissolution or desorption) to the aqueous phase in which microbial uptake occurs [2][3][4][5], or micelle-associated PAHs are directly available to PAH-degrading microbes via direct contact between micelles and microbes [6,7]. The extent of stimulation varies with the type and concentration of surfactants and the type of microorganisms involved [8][9][10][11][12][13]. Conversely, others have reported surfactant additions to inhibit, or at least not enhance, PAH biodegradation [14][15][16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Polycyclic aromatic hydrocarbon behavior in bioactive soil slurry reactors amended with a nonionic surfactant

Kim

Weber

2005

Enviro Toxic and Chemistry

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The effects of an ethoxylated sorbitan fatty ester nonionic surfactant (Tween 80) on the bioavailability of polycyclic aromatic hydrocarbons (PAHs) were examined by using soil-free and dense-slurry (67% solids content, by wt) systems containing a creosote-contaminated field soil. The dispersed-micelle-phase PAHs in soil-free systems were not readily bioavailable to the mixed consortium of microbes indigenous to the creosote-contaminated soil. Instead, the microbes partially and preferentially utilized readily available portions of the surfactant as carbon sources (16-18% of the initial surfactant dose). This selective microbial attack resulted in destabilization of dispersed-phase micelles and significant decreases in molar solubilization ratio and micelle-water partition coefficient values. Remarkably high dosages (>20 g/L) of Tween 80 were required to enhance mobilization of the sorbed PAHs via micelle association because of the sorption of Tween 80 to the soil employed. The PAHs released from the destabilized micelles in soil-slurry systems either associated with sorbed-phase surfactants or readsorbed to soil organic matter too rapidly to be biologically accessed, even by the acclimated PAH-degrading microbes present. The work provides important new information and practical insights to surfactant solubilization and mobilization technology applications for the bioremediation of PAH-contaminated soils and sediments.

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Section: Introductionmentioning

confidence: 99%

Polycyclic aromatic hydrocarbon behavior in bioactive soil slurry reactors amended with a nonionic surfactant

Kim

Weber

2005

Enviro Toxic and Chemistry

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“…Guerin and Jones [16] evaluated the effect of several Tween surfactants on the bacterial utilization of polycyclic aromatic hydrocarbons and found Tween-60 to be more successful in enhancing the growth of a Mycobacterium sp. on phenanthrene than Tween-85, -80, -40, or -20 (listed in order of decreasing rate of phenanthrene utilization).…”

Section: Discussionmentioning

confidence: 99%

“…However, Tween-80 may not be the most ideal surfactant for use in biological systems. Reports in the literature [8,16] and preliminary testing in our laboratory (unpublished data) have indicated instances in which Tween-80 was less successful in promoting the biotransformation of HOCs compared with other members of the Tween series. Consequently, all Tween surfactants need to be examined individually to assess the effect of their structural differences on biological processes to identify the most favorable Tween surfactants for use in bioavailability applications.…”

Section: Introductionmentioning

confidence: 91%

Effect of Tween Surfactants on Methanogenesis and Microbial Reductive Dechlorination of Hexachlorobenzene

Yeh¹,

Pennell²,

Pavlostathis³

1999

Environ Toxicol Chem

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The effect of nine Tween surfactants (polyoxyethylene sorbitan fatty acid esters) on methanogenesis and the microbial reductive dechlorination of hexachlorobenzene (HCB) was examined using three anaerobic, HCB-dechlorinating mixed cultures, one glucose fed and two lactate fed, that were derived from contaminated estuarine sediments. The two lactate-fed cultures differed significantly in their metabolic activity, especially with respect to the rate and extent of HCB reductive dechlorination. The objective of the study was to screen and select biologically compatible surfactants for use in subsequent research on surfactant-enhanced bioavailability of sorbed-phase chlorinated organic contaminants. Addition of the Tween surfactants resulted in lower rates of methanogenesis and HCB dechlorination compared with the control (i.e., surfactant-free culture) for both the glucose-fed culture and the lactate-fed culture, which exhibited a high metabolic activity. Tween-61 and -65 exhibited the lowest inhibition of HCB dechlorination at initial surfactant concentrations of 200 and 1,000 mg/L. On the other hand, the Tween surfactants, especially Tween-81 and -85, enhanced the rates of both methanogenesis and HCB dechlorination when the low metabolic activity lactatefed culture was used. The observed rate enhancements may be attributed to bacterial cell membrane modification by the surfactants. Attempts to correlate methanogenesis rates to surfactant properties (such as the hydrophile-lipophile balance number, fatty acid carbon chain length, and the number of ethylene oxide groups) were not successful. In general, increased surfactant concentrations resulted in lower rate and extent of HCB dechlorination. Although HCB dechlorination was completely inhibited at a surfactant concentration of 1,000 mg/L, the extent of methanogenesis was not affected. Results from this study demonstrate that despite compositional similarities among the Tween surfactants, their effects on biological activities, such as methanogenesis and reductive dechlorination, can differ significantly. Keywords-HexachlorobenzeneMethanogenesis Nonionic surfactants Reductive dechlorination Tween surfactants Effect of surfactants on methanogenesis and dechlorination

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“…Two other studies, using a series of Tweens with HLB values between 10 and 17, observed maximum degradation of phenanthrene [13] and alkanes [11] with addition of the more lipophilic surfactant, Tween 85 (HLB ϭ 11). Assuming that the rate of hydrocarbon dissolution limited bioavailability, the authors suggested that the lower cmc of the more lipophilic surfactants resulted in increased interfacial area, enhancing hydrocarbon utilization.…”

Section: Interactions Of Surfactants With Microbial Membranesmentioning

confidence: 96%

“…Most studies that have examined surfactant effects on microbial HOC degradation have looked at hydrocarbon utilization by pure cultures in aqueous media. Several of these studies, using a variety of nonionic surfactants, demonstrated a positive effect on microbial growth concurrent with enhanced degradation of hydrocarbon substrate [1,2,5,[11][12][13][14][15]. Generally, no evidence of surfactant degradation was observed.…”

Section: Introductionmentioning

confidence: 99%

Reductive dechlorination of chlorobenzenes in surfactant‐amended sediment slurries

Hoof

Jafvert

1996

Enviro Toxic and Chemistry

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Microbial anaerobic dechlorination of hexachlorobenzene (HCB) was examined in sediment slurries amended with two classes of nonionic surfactant, polyoxyethylene (POE) sorbitan fatty acid esters (Tweens) and POE alcohols (Brijs). The rationale for surfactant addition was to increase the bioavailability of highly sorbed organic pollutants to degrading microorganisms by enhancing their solubility. The solubility of HCB was initially enhanced via micellar partitioning; however, primary degradation of most surfactants occurred within 10 d. Dechlorination activity was significantly reduced at POE alcohol concentrations above the critical micelle concentration (cmc), with or without the occurrence of surfactant degradation. Tween 80 decreased HCB dechlorination at concentrations significantly above the cmc (1,500–5,000 mg/L). At concentrations closer to the cmc (300–1,200 mg/L), Tween 80 increased dechlorination rate constants four‐ to fivefold in acclimated slurries. Additions of Tween 80 at or below the cmc (3, 30, 300, and 911 mg/L) stimulated dechlorination activity in unacclimated slurries that exhibited very little activity in unamended controls. An average of 89% of HCB was dechlorinated after 90 d, compared to 20% in unamended sediments. No effect was observed for POE alcohols at these sub‐cmc levels. The lack of a stimulated response for the POE alcohols suggests that Tween 80 may not be acting simply as a source of carbon or energy.

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Mineralization of phenanthrene by a Mycobacterium sp

Cited by 180 publications

References 42 publications

Polycyclic aromatic hydrocarbon behavior in bioactive soil slurry reactors amended with a nonionic surfactant

Polycyclic aromatic hydrocarbon behavior in bioactive soil slurry reactors amended with a nonionic surfactant

Effect of Tween Surfactants on Methanogenesis and Microbial Reductive Dechlorination of Hexachlorobenzene

Reductive dechlorination of chlorobenzenes in surfactant‐amended sediment slurries

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