Seyed Abbas Shojaosadati
Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, P.O. Box 14115-143 Tehran, I.R. IRAN
[ 1 ] - The Effect of Mg2+ and Mn2+ on Over-Production of Interleukin-2 in Recombinant E.coli
In order to increase the productivity of human interleukin-2 (IL-2) as a model protein in the recombinant E.coliBL21 (DE3), the effect of magnesium acetate and manganese acetate was studied based on full factorial design experiments magnesium acetate and manganese acetate and their interaction exhibited an increasing effect on IL-2 expression level upto 25.24%, 16.80% and 23.30%, respective...
[ 2 ] - Mixing Studies in Loop Bioreactors for Production of Biomass from Natural Gas
The mixing behavior of the gas-liquid phase in three loop bioreactors was investigated. A gas-induced External Airlift Loop Bioreactor (EALB), a forced-liquid Vertical Tubular Loop Bioreactor (VTLB) and a forced-liquid Horizontal Tubular Loop Bioreactor (HTLB) were used for mixing studies as well as biomass production from natural gas. The effect of design parameters, riser to downcomer cro...
[ 3 ] - Bioleaching of Low Grade Uranium Ore of Saghand Mine
This study deals with bioleaching of the low grade uranium ore of Saghand mine in Iran using a mixed culture of mesophilic bacteria (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans). Experiments were carried out in shaking flask examining the effect of temperature, initial ferrous ion concentration, pulp density and particle size. Variations of ...
[ 4 ] - Comparison of Different Loop Bioreactors Based on Hydrodynamic Characteristics, Mass Transfer, Energy Consumption and Biomass Production from Natural Gas
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 ...
[ 5 ] - On-Line Measurement of Dissolved Methane Concentration During Methane Fermentation in a Loop Bioreactor
A dissolved methane sensor based on silicone tube was designed, constructed and optimized.The silicone tube diameter, silicone tube length and helium flow rate (as the carrier gas(were considered as process parameters to be optimized.A continuous stream of helium (50 mL/min) was directed through the tubing, sweeping out the...
[ 6 ] - Media Selection for Poly(hydroxybutyrate) Production from Methanol by Methylobacterium Extorquens DSMZ 1340
Plackett-Burman design was used for selection of important media components such as carbon and nitrogen sources and minerals which affect poly(hydroxybutyrate) production and cell growth of Methylobacterium extorquens DSMZ 1340. Among the studied variables, nitrogen and phosphorus sources, MgSO4 and most of the trace elements were found to be significant variables for PHB product...
[ 7 ] - Surface Coating of Red Blood Cells with Monomethoxy poly(ethylene glycol) Activated with Two Different Reagents
Methoxy poly(ethylene glycol) (mPEG) with molecular mass of 5 kDa activated with succinimidyl carbonate and cyanuric chloride, separately was covalently attached to human red blood cells (RBCs). Inhibition of agglutination by blood-type specific antisera (anti-D) was employed to evaluate the effect of the polymer coating. The remaining single cells after incubation with anti-D sera were cou...
[ 8 ] - Determination of Bio-Oxidation Energy Released by Thermophiles in Secondary and Mixed Bio-Solids
Reaction constants and heat release during thermophilic aerobic digestion of typical secondary and mixed sludges were determined. Maximum reaction constant, determined by measuring the amounts of biodegradable volatile suspended solids (bVSS) removed, occurred in the temperature range of 55-60 ºC. Measurement of heat releases were carried out, at the same range, by the aid of a temperature ...
[ 9 ] - Biodegradation of Polycyclic Aromatic Hydrocarbons by Aerobic Mixed Bacterial Culture Isolated from Hydrocarbon Polluted Soils
In this study, the degradation potential of five polycyclic aromatic hydrocarbons (PAHs) by aerobic mixed bacterial cultures was investigated. Microorganisms were isolated from hydrocarbon contaminated soils of Shadegan wetland located in southwest of Iran. The degradation experiments were conducted in liquid cultures. PAH or PAHs concentration was 100 mg/L at the beginning of degradation e...
[ 10 ] - Thermophilic Aerobic Digestion of Activated Sludge; Reduction of Solids and Pathogenic Microorganisms
In the temperature range of 10 to 80 ºC and in a batch digester, a typical activated sludge was digested aerobically. Reaction rate constants were determined by measuring the amounts of volatiles removed from the suspended solids at different time intervals during the process. The maximum value of the reaction rate constant (0.45 d-1) occurred in the temperature...
[ 11 ] - Optimizing of SCP Production from Sugar Beet Stillage Using Isolated Yeast
In this study fungi isolated from the effluent of ethanol factories were identified. Optimal conditions for single cell protein (SCP) production and COD reduction of sugar beet stillage are specified for a species of Hansenula in a continuous culture. Under these conditions 5.7 g dm-3 biomass was produced and 31% of COD was reduced without addition of further nutrients to the beet molasses ...