Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1021/es001552k
Title (Primary) Influence of the nonionic surfactant Brij 35 on the bioavailability of solid and sorbed dibenzofuran
Author Garcia, J.M.; Wick, L.Y.; Harms, H.
Source Titel Environmental Science & Technology
Year 2001
Department UMB
Volume 35
Issue 10
Page From 2033
Page To 2039
Language englisch
Abstract The effect of the nonionic surfactant Brij 35 on the bioavailability of solid and Teflon-sorbed dibenzofuran for Sphingomonas sp. strain HH19k was studied in simple model systems. Growth with dibenzofuran and dibenzofuran-specific oxygen uptake in surfactant-free media and with Brij 35 above the critical micelle concentration (cmc) were compared with dissolution and desorption in the absence of bacteria. Brij 35 accelerated dissolution and biodegradation of solid dibenzofuran by a factor of 2. It also enhanced the initial desorption rate of dibenzofuran from Teflon by this factor. Continuously decreasing desorption rates were attributed to slow diffusion of dibenzofuran inside Teflon, leading to depletion of dibenzofuran in the exterior of the Teflon particles. Surprisingly, Brij 35 slowed the initial biodegradation of desorbing dibenzofuran. We propose two processes that led to low bioavailability of sorbed dibenzofuran in the presence of surfactant. First, desorbing dibenzofuran rapidly accumulated in surfactant micelles, leading to reduced truly water-dissolved dibenzofuran concentration as the factor controlling the biodegradation rate. Second, Brij 35 suppressed the contact between bacteria and Teflon. This increased the average diffusion distance of dibenzofuran to the bacteria, which in turn flattened the gradient of the dissolved dibenzofuran concentration between the sorbent and the cells as the driving force for desorption.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=6335
Garcia, J.M., Wick, L.Y., Harms, H. (2001):
Influence of the nonionic surfactant Brij 35 on the bioavailability of solid and sorbed dibenzofuran
Environ. Sci. Technol. 35 (10), 2033 - 2039 10.1021/es001552k