Calcium gluconate production by Aspergillus niger was investigated in shake flask, rolling shaker, air-lift reactor and stirred reactor. Growth pattern of the organism and fermentation conditions determined the yield of the product. High calcium gluconate production was achieved in air-lift reactor with pellet form of cell growth at moderate specific growth rate and biomass concentration. In an...

the performance of a forced-liquid vertical tubular loop bioreactor (vtlb), a forced-liquid horizontal tubular loop bioreactor (htlb) and a gas-induced external airlift loop bioreactor (ealb) were compared for production of biomass from natural gas. hydrodynamic characteristics and mass transfer coefficients were determined as functions of design parameters, physical properties of gases as well...

PURPOSE This study is conducted to develop a simplified mathematical model to describe the lift mechanics of downhill skiing and snowboarding, where the lift contributions due to both the transiently trapped air and the compressed solid phase (snow crystals) are determined. To our knowledge, this is the first time that anyone has attempted to realistically estimate the relative contribution of ...

In this study, a numerical computational fluid dynamics study is conducted in order to predict the aerodynamic forces on the NP car. The turbulent air flow around the car is modeled using the realizable k-ε model. First, results are validated against those presented for the Ahmed’s body. Next, the fluid flow around the car is simulated for different car speeds ( to mph) and fl...

Polygalacturonase production under different shear stress environments by Aspergillus sp. was studied. It was found that the rate of enzyme production in the stirred tank fermentor decreased with increasing the stirrer speed in the range 300-750 rpm. On the other hand, in a split cylinder air-lift fermentor, the rate of polygalacturonase production slightly increased with increasing in air ...

in this study, a numerical computational fluid dynamics study is conducted in order to predict the aerodynamic forces on the np car. the turbulent air flow around the car is modeled using the realizable k-ε model. first, results are validated against those presented for the ahmed’s body. next, the fluid flow around the car is simulated for different car speeds ( to mph) and flow directions ( to...

BACKGROUND Dissolved oxygen tension (DOT) is hardly constant and homogenously distributed in a bioreactor, which can have a negative impact in the metabolism and product synthesis. However, the effects of DOT on plasmid DNA (pDNA) production and quality have not been thoroughly investigated. In the present study, the effects of aerobic (DOT ≥30% air sat.), microaerobic (constant DOT = 3% air sa...

Use of methyl bromide (MeBr) as a quarantine, commodity, or structural fumigant is under scrutiny because its release to the atmosphere contributes to the depletion of stratospheric ozone. A closed-system bioreactor consisting of 0.5 L of a growing culture of a previously described bacterium, strain IMB-1, removed MeBr (> 110 micromol L(-1)) from recirculating air. Strain IMB-1 grew slowly to h...