title: An industrial scale process for the enzymatic removal of steryl glucosides from biodiesel.
abstract: BACKGROUND
  Biodiesels produced from transesterification of vegetable oils have a major quality problem due to the presence of precipitates, which need to be removed to avoid clogging of filters and engine failures. These precipitates have been reported to be mostly composed of steryl glucosides (SGs), but so far industrial cost-effective methods to remove these compounds are not available. Here we describe a novel method for the efficient removal of SGs from biodiesel, based on the hydrolytic activity of a thermostable β-glycosidase obtained from Thermococcus litoralis.
  
  
  RESULTS
  A steryl glucosidase (SGase) enzyme from T. litoralis was produced and purified from Escherichia coli cultures expressing a synthetic gene, and used to treat soybean-derived biodiesel. Several optimization steps allowed for the selection of optimal reaction conditions to finally provide a simple and efficient process for the removal of SGs from crude biodiesel. The resulting biodiesel displayed filterability properties similar to distilled biodiesel according to the total contamination (TC), the cold soak filtration test (CSFT), filter blocking tendency (FBT), and cold soak filter blocking tendency (CSFBT) tests. The process was successfully scaled up to a 20 ton reactor, confirming its adaptability to industrial settings.
  
  
  CONCLUSIONS
  The results presented in this work provide a novel path for the removal of steryl glucosides from biodiesel using a cost-effective, environmentally friendly and scalable enzymatic process, contributing to the adoption of this renewable fuel.
authors.affiliation: Genetic Engineering and Fermentation Technology, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario-Conicet, Suipacha 531, Rosario, 2000 Argentina.|Keclon S.A., Tucuman 7180, Rosario, 2000 Argentina.
authors.forename: Salvador
authors.initials: S
authors.lastname: Peiru
authors.affiliation: Genetic Engineering and Fermentation Technology, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario-Conicet, Suipacha 531, Rosario, 2000 Argentina.|Keclon S.A., Tucuman 7180, Rosario, 2000 Argentina.
authors.forename: Andres
authors.initials: A
authors.lastname: Aguirre
authors.affiliation: Genetic Engineering and Fermentation Technology, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario-Conicet, Suipacha 531, Rosario, 2000 Argentina.
authors.forename: Florencia
authors.initials: F
authors.lastname: Eberhardt
authors.affiliation: Genetic Engineering and Fermentation Technology, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario-Conicet, Suipacha 531, Rosario, 2000 Argentina.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Braia
authors.affiliation: Unitec Bio S.A., Batalla del Quebracho s/n, Pto. Gral, San Martín, 2202 Argentina.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Cabrera
authors.affiliation: Genetic Engineering and Fermentation Technology, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario-Conicet, Suipacha 531, Rosario, 2000 Argentina.|Keclon S.A., Tucuman 7180, Rosario, 2000 Argentina.
authors.forename: Hugo G
authors.initials: HG
authors.lastname: Menzella
keywords: Biofuels; Green chemistry; Synthetic biology