Optimization of the heterologous production of a Rhizopus oryzae lipase in Pichia pastoris system using mixed substrates on controlled fed-batch bioprocess

Effect of dilution rate and methanol‐glycerol mixed feeding on heterologous Rhizopus oryzae lipase production with Pichia pastorisMut+ phenotype in continuous culture

“…The time evolution of a continuous fermentation is shown in Figure 1 as an example of parameter variation during the production process. 31 The biomass concentration ranged between 1.8 and 3.9 g L 21 , and was strongly affected by the operational variables (Figure 2a). Because glycerol was totally consumed, its contribution to biomass formation was proportional to glycerol concentration fed according to the expression Gly 0 3 Y X/G , considering a constant yield within the D range tested.…”

Immobilization and stability of a Rhizopus oryzae lipase expressed in Pichia pastoris: Comparison between native and recombinant variants

“…This lipase is obtained by a fed-batch cultivation of a recombinant Pichia pastoris strain using methanol as inducer. 34 The culture broth was centrifuged and microfiltered to remove the biomass. The supernatant was concentrated by ultrafiltration with a Centrasette V R Pall Filtron (Pall, New York) system equipped with an Omega membrane of 10 kDa cut-off, and dialyzed against 10 mM Tris-HCl buffer, pH 7.5, and thereafter lyophilized.…”

“…It is important to stress that rROL showed a 40-fold higher specific activity compared with the nROL and a higher specificity toward p-nitrophenol esters of long chain length. 32 In this work, the immobilization of an extract containing a rROL produced in Pichia pastoris 34 has been carried out on two different kinds of supports: polypropylene powder EP100 and Eupergit V R C. The immobilization experiments were also carried out for the nROL to compare their behaviors. The stability of both lipases on each support was assessed to determine whether an improvement of the enzyme stability occurred.…”

Real-time monitoring and control of microbial bioprocesses with focus on the specific growth rate: current state and perspectives

“…Feed-forward control by a priori calculation of an exponential feed trajectory, based on a simple combination of mass balances and Eq. 1, has been widely exploited to maintain μ constant throughout the culture (Pico-Marco et al 2005;Ren and Yuan 2005;Babaeipour et al 2007;Jungo et al 2007;Warth et al 2010;Chenikher et al 2010;Arnau et al 2010;Chen et al 2011). The mathematical description of the exponential feed trajectory is given in Eq.…”