title: Immobilization of hydrocarbon-oxidizing bacteria in poly(vinyl alcohol) cryogels hydrophobized using a biosurfactant.
abstract: A simple biosurfactant-based hydrophobization procedure for poly(vinyl alcohol) (PVA) cryogels was developed allowing effective immobilization of hydrocarbon-oxidizing bacteria. The resulting partially hydrophobized PVA cryogel granules (granule volume 5 microl) contained sufficient number (6.5 x 10(3)) of viable bacterial cells per granule, possessed high mechanical strength and spontaneously located at the interface in water-hydrocarbon system. Such interfacial location of PVA granules allowed high contact of immobilized biocatalyst with hydrophobic substrate and water phase, thus providing bacterial cells with mineral and organic nutrients. As a result, n-hexadecane oxidation efficiency of 51% after 10-day incubation was achieved using immobilized biocatalyst. PVA cryogels with increased hydrophobicity can be used for immobilization of bacterial cultures performing oxidative transformations of water-immiscible organic compounds. Immobilization of in situ biosurfactant producing Rhodococcus bacteria into PVA cryogel is discussed. PVA cryogel granules with entrapped alkanotrophic rhodococcal cells were stable after 10-month storage at room temperature.
authors.affiliation: Institute of Ecology and Genetics of Microorganisms, Ural Branch of Russian Academy of Sciences, Perm. kuyukina@iegm.ru
authors.forename: Maria S
authors.initials: MS
authors.lastname: Kuyukina
authors.forename: Irena B
authors.initials: IB
authors.lastname: Ivshina
authors.forename: Alexander Yu
authors.initials: AY
authors.lastname: Gavrin
authors.forename: Elena A
authors.initials: EA
authors.lastname: Podorozhko
authors.forename: Vladimir I
authors.initials: VI
authors.lastname: Lozinsky
authors.forename: Chris E
authors.initials: CE
authors.lastname: Jeffree
authors.forename: James C
authors.initials: JC
authors.lastname: Philp
mesh_terms: D000473:Alkanes / Q000378:metabolism; D001673:Biodegradation, Environmental; D001798:Blood Proteins / Q000737:chemistry; D018914:Cells, Immobilized; D059985:Cryogels; D015925:Cryopreservation / Q000379:methods; D005353:Fibronectins / Q000737:chemistry; D006838:Hydrocarbons / Q000378:metabolism*; D020100:Hydrogels; D057927:Hydrophobic and Hydrophilic Interactions; D010084:Oxidation-Reduction; D011136:Polysorbates / Q000378:metabolism; D011142:Polyvinyl Alcohol; D012240:Rhodococcus / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D013501:Surface-Active Agents / Q000378:metabolism*
chemical_list: D000473:Alkanes; D001798:Blood Proteins; D059985:Cryogels; D005353:Fibronectins; D006838:Hydrocarbons; D020100:Hydrogels; D011136:Polysorbates; D013501:Surface-Active Agents; D011142:Polyvinyl Alcohol; C007932:n-hexadecane