The role of volumetric power input in the growth, morphology, and production of a recombinant glycoprotein by Streptomyces lividans in shake flasks

A hydrodynamic description of the flow behavior in shaken flasks

“…Beyond this threshold value of 150 rpm, the shaking speed did not cause an increase of the turbulent intensity average value. This finding is in agreement with previous reports [17,20]. The velocity fluctuations generated in each of the indentations interacted with the flow fluctuation generated in the next baffle, promoting their rapid dissipation.…”

“…We can conclude that the baffled flasks have a nearly homogeneous turbulent distribution with large intensity values in comparison with the coiled flask. Although in previous works similar agitation rate or power input was used between conventional, coiled and baffled flasks different physiological responses were observed in filamentous recombinant bacterial cultures [17,20], surely due to homogeneous distribution of the turbulent intensity. In particular, the one-baffle configuration showed better hydrodynamic performance.…”

“…At this operating condition the fluid was mixed in the walls but in the center of the container, no significant streams were observed. When the shaking speed was increased to 150 rpm, which is similar to the agitation velocity at which microorganisms cultures are produced [17,19,20], the liquid moved in the shaking direction close to the walls, which consequently produced significant fluid streams. As shown in Fig.…”

The flow inside shaking flasks and its implication for mycelial cultures

“…They performed experiments at different shaking velocities ranging from 25 to 250 rpm. They found that at high shaking rates the turbulent distribution increased for all flask configurations; however, the highest turbulent production for all geometric conditions occurred at a shaking speed of about 150 rpm which is the frequency used by different authors (Gamboa-Suasnavart et al, 2011Marín-Palacio et al, 2014). Rodríguez et al (2015) reported a study on the effect of a conical bottom flask in an orbital shaker.…”

“…The authors firstly attributed these significant differences to the aeration/ hydrodynamic stresses generated by the flask configuration. Moreover, dissimilar volumetric power inputs for the three configurations were observed for the same shaking velocity (Marín-Palacio et al, 2014). More recently, Mancilla et al (2015) studied the flow behavior in shaken flasks using the PIV technique based on Gamboa-Suasnavart et al (2011) flask configurations.…”