title: Immobilization of Pseudomonas fluorescens lipase on hydrophobic supports and application in biodiesel synthesis by transesterification of vegetable oils in solvent-free systems.
abstract: This work describes the preparation of biocatalysts for ethanolysis of soybean and babassu oils in solvent-free systems. Polystyrene, Amberlite (XAD-7HP), and octyl-silica were tested as supports for the immobilization of Pseudomonas fluorescens lipase (PFL). The use of octyl-silica resulted in a biocatalyst with high values of hydrolytic activity (650.0 ± 15.5 IU/g), immobilization yield (91.3 ± 0.3 %), and recovered activity (82.1 ± 1.5 %). PFL immobilized on octyl-silica was around 12-fold more stable than soluble PFL, at 45 °C and pH 8.0, in the presence of ethanol at 36 % (v/v). The biocatalyst provided high vegetable oil transesterification yields of around 97.5 % after 24 h of reaction using babassu oil and around 80 % after 48 h of reaction using soybean oil. The PFL-octyl-silica biocatalyst retained around 90 % of its initial activity after five cycles of transesterification of soybean oil. Octyl-silica is a promising support that can be used to immobilize PFL for subsequent application in biodiesel synthesis.
authors.affiliation: Graduate Program in Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luiz, km 235, São Carlos, SP, 13565-905, Brazil.
authors.forename: Lionete N
authors.initials: LN
authors.lastname: Lima
authors.forename: Gladson C
authors.initials: GC
authors.lastname: Oliveira
authors.forename: Mayerlenis J
authors.initials: MJ
authors.lastname: Rojas
authors.forename: Heizir F
authors.initials: HF
authors.lastname: Castro
authors.forename: Patrícia C M
authors.initials: PC
authors.lastname: Da Rós
authors.forename: Adriano A
authors.initials: AA
authors.lastname: Mendes
authors.forename: Raquel L C
authors.initials: RL
authors.lastname: Giordano
authors.forename: Paulo W
authors.initials: PW
authors.lastname: Tardioli
mesh_terms: D055162:Biocatalysis; D056804:Biofuels / Q000600:supply & distribution*; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D004951:Esterification; D000431:Ethanol; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D008049:Lipase / Q000737:chemistry* / Q000378:metabolism*; D010938:Plant Oils / Q000737:chemistry / Q000378:metabolism*; D011551:Pseudomonas fluorescens / Q000201:enzymology*; D012822:Silicon Dioxide / Q000737:chemistry; D012997:Solvents; D013024:Soybean Oil / Q000737:chemistry / Q000378:metabolism; D013696:Temperature
chemical_list: D056804:Biofuels; D004800:Enzymes, Immobilized; D010938:Plant Oils; D012997:Solvents; D000431:Ethanol; D012822:Silicon Dioxide; D013024:Soybean Oil; D008049:Lipase