The hyperthermophilic archaeon Thermococcus hydrothermalis was cultivated in continuous culture in a gas-lift bioreactor in the absence of elemental sulphur on both proteinaceous and maltose-containing media. Optimal conditions (pH, temperature and gas flow rate), determined on complex media that yielded maximal growth rate and maximal steady state cell density, were obtained at 80 degrees C, p...

The microflora developing during a continuous enrichment culture from a hydrothermal chimney sample was investigated by molecular methods. The culture was performed in a gas-lift bioreactor under anaerobic conditions, at 90°C and pH 6.5, on a complex medium containing sulfur as the terminal electron acceptor. Archaeal and bacterial diversity was studied. Microorganisms affiliated with the gener...

selected genotypes of sugar beet are often maintained by conventional propagation, but much faster rates of multiplication can be now obtained through micropropagation. on the other hand, plant micropropagation using bioreactors can decrease the cost of production and makes it an economical method. in this research, the possibility of using bioreactor and optimization of the tissue culture proc...

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 rate...

α-Galactosidase production by the fungal strains Penicillium chrysogenum LN33 and Aspergillus niger M47 cultivated in shaking and stationary conditions using soya meal extract as nutrient medium was investigated. Submerged shake flask fermentation was preferred over stationary cultivation for P. chrysogenum LN33 as it gave a high α-galactosidase yield (4200U/l). Because of pellet formation the ...

The magnetostrictive guided wave technology as a non-contact measurement can generate and receive guided waves with a large lift-off distance up to tens of millimeters. However, the lift-off distance of the receiving coil would affect the coupling efficiency from the elastic energy to the electromagnetic energy. In the existing magnetomechanical models, the change of the magnetic field in the a...

A simple biodegradation system consisting of an air stripping tank and a bioreactor was proposed for the treatment of volatile organic chemicals in wastewater. Toluene was used as a model of volatile organic chemicals. An aqueous solution of toluene and a basic mineral medium were placed in the air stripping tank and bioreactor, respectively. Toluene was stripped by supplying compressed air int...