Encapsulation of Pseudomonas sp. ADP cells in electrospun microtubes for atrazine bioremediation

Abstract

Electrospun hollow polymeric microfibers (microtubes) were evaluated as an encapsulation method for the atrazine degrading bacterium Pseudomonas sp. ADP. Pseudomonas sp. ADP cells were successfully incorporated in a formulation containing a core solution of polyethylene oxide dissolved in water and spun with an outer shell solution made of polycaprolactone and polyethylene glycol dissolved in a chloroform and dimethylformamide. The resulting microtubes, collected as mats, were partially collapsed with a ribbon-like structure. Following encapsulation, the atrazine degradation rate was low (0.03 ± 0.01 mg atrazine/h/g fiber) indicating that the electrospinning process negatively affected cell activity. Atrazine degradation was restored to 0.5 ± 0.1 mg atrazine/h/g fiber by subjecting the microtubes to a period of growth. After 3 and 7 days growth periods, encapsulated cells were able to remove 20.6 ± 3 and 47.6 ± 5.9 mg atrazine/g mat, respectively, in successive batches under non-growth conditions (with no additional electron donor) until atrazine was detected in the medium. The loss of atrazine degrading capacity was regained following an additional cell-growth period.

Living Composites of Bacteria and Polymers as Biomimetic Films for Metal Sequestration and Bioremediation

“…The microbial composition of naturally established biofilms is hard to influence, which is less of a concern in environmental applications of microbial consortia, but becomes preemptive in case of specific chemical transformation to be executed by an isolated microbial species. The ability to purposely design biomimetic extracellular matrices containing defined microbial species/consortia and with controlled properties would be a major advance for bioconversion …”

Evaluation of contact time and fiber morphology on bacterial immobilization for development of novel surfactant degrading nanofibrous webs

“…11,[20][21][22][23][24] In the current study, Serratia proteamaculans STB3 and Achromobacter xylosoxidans STB4 cells, which have biodegradation capabilities on a known anionic surfactant: sodium dodecyl sulfate (SDS), were immobilized onto cellulose acetate nanobers that have either non-porous or porous morphology to obtain reusable materials for surfactant remediation in aqueous systems. We describe here the development procedure of bacteria immobilized biocomposites and their potential reusability.…”

Bioactive Applications for Electrospun Fibers

“…10,11 Multi-axial (coaxial/triaxial) electrospinning consisting of spinneret components which enable the simultaneous spinning of different liquids, deserve particular attention as they are proposed for the fabrication of the more complex functional nanofibers. 12 The use of rotating devices such as drums, mandrels, and disks with different geometry and morphology (solid or frame cylinders and various edge morphologies) can be used to obtain highly aligned fibers or for improving conformability and scalability. Of particular interest from the industrial point of view is the singular capability of electrospinning to give rise to complex bi-and tri-dimensional architectures in a single run, for which a proper collector design is essential.…”

“…The encapsulation of the atrazine degrading bacterium Pseudomonas sp. ADP was studied in hollow polymeric electrospun microfibers by Klein et al 12 It is a strain that rapidly mineralizes atrazine under aerobic and denitrifying conditions as well as under non-growth conditions and was included within the core of a hollow fiber. A core solution of PEO dissolved in water was spun with an outer shell made of PCL and PEG.…”