Estimation of Kinetic Parameters for Bioremediation of Cr(VI) from Wastewater UsingPseudomonas taiwanensis,an Isolated Strain from Enriched Mixed Culture

2014 ◽  
Vol 18 (3) ◽  
pp. 236-247 ◽  
Author(s):  
Subhajit Majumder ◽  
Smita Raghuvanshi ◽  
Suresh Gupta
1991 ◽  
Vol 38 (8) ◽  
pp. 813-820 ◽  
Author(s):  
Cees J. N. Buisman ◽  
Peter I Jspeert ◽  
Anne Hof ◽  
Albert J. H. Janssen ◽  
Robert Ten Hagen ◽  
...  

2003 ◽  
Vol 47 (10) ◽  
pp. 123-130 ◽  
Author(s):  
H. Feitkenhauer ◽  
H. Märkl

In this paper, the high temperature (65-75°C) biodegradation of aliphatic and aromatic hydrocarbons is investigated and kinetic parameters are derived. The shift of the physico-chemical system properties with rising temperature will be discussed in detail. For example, the solubility of naphthalene is increased by a factor of about ten if the temperature is increased from 20 to 75°C. This effect is essential to increase the bioavailability of sparingly soluble hydrocarbons. It is also demonstrated in experiments that very high oxygen transfer rates can be obtained at high temperatures in the presence of hydrocarbons. It is shown that efficient phenol biodegradation is essential for high temperature hydrocarbon degradation because some microorganisms tend to transform phenols into polyphenols which are very inhibitory for microbial growth. A defined mixed culture adapted to phenol converted more than 90% of a mixture of phenol, hexadecane and pyrene and a very high maximal growth rate of 0.19 h−1 was determined. A yield coefficient YX/S of about 0.8 g (biomass)/g (hydrocarbons) was calculated in this experiment. In a separate experiment the influence of the hydrocarbon droplet size on the biodegradation is investigated at 70°C using a newly isolated Thermus sp. In this case, the growth on a hexadecane/pyrene mixture was described by a model based on the Monod equation and the corresponding kinetic parameters are derived. A mixed culture was used for the bioremediation of soil in a slurry reactor. The initial contamination of 11 g/kg was lowered to about 2 g in a reactor inoculated by an immobilized culture of extreme thermophilic microorganisms, while 9 g/kg remained in a sterile control.


1970 ◽  
Vol 65 (1_Suppl) ◽  
pp. S104-S121 ◽  
Author(s):  
E. E. Baulieu ◽  
J. P. Raynaud ◽  
E. Milgrom

ABSTRACT A brief review of the characteristics of steroid binding proteins found in the plasma and in some target organs is presented, followed by some general remarks on binding »specificity« and binding parameters. Useful techniques for measuring binding parameters at equilibrium are reported, both those which keep the equilibrium intact and those which implicate its disruption. A concept is developed according to which the determination of a specific steroid binding protein is based on the »differential dissociation« of the several steroid binding complexes present in most biological mixtures. Methods which allow determination of the kinetic parameters of the binding systems are also presented. Various representations of the binding and therefore different modes of graphic representation and calculation are discussed, including the recent »proportion graph« method.


1974 ◽  
Vol 76 (1) ◽  
pp. 178-188 ◽  
Author(s):  
H. Lübbert ◽  
K. Pollow ◽  
R. Wagner ◽  
J. Hammerstein

ABSTRACT The effects of ethanol on kinetic parameters of placental Δ5-3β-hydroxysteroid dehydrogenase were studied. In the presence of high pregnenolone concentrations (50 μm, [S] > Km) the microsomal enzyme preparation exhibited an almost linear increase in activity as the ethanol concentration in the medium was raised from 2.5 to 15 % (v/v). At lower substrate concentrations ([S] << Km) ethanol caused inhibition. Other effects of ethanol were: linearity of product formation with time was prolonged; the maximal velocity was markedly increased; the Km for pregnenolone slightly decreased with increasing ethanol concentrations (2.5 to 10 %, v/v) whereas the Km for NAD remained the same. The pH and temperature optima of the reaction were unaffected by ethanol. Other organic solvents caused similar effects.


2017 ◽  
Vol 68 (5) ◽  
pp. 903-907
Author(s):  
Ecaterina Anca Serban ◽  
Ioana Diaconu ◽  
Elena Ruse ◽  
Georgiana Ileana Badea ◽  
Adriana Cuciureanu ◽  
...  

Indole-3-acetic acid is a growth phytohormone considered the most important representative of auxin class. This paper presents the assessment of some kinetic parameters in the process of transport of indole-3-acetic acid taking into consideration the kinetic model of consecutive irreversible first order reactions. It was pursued the influence upon the process of parameters such as: feed phase concentration, stripping phase concentration in the presence of two type carriers: tributyl phosphate (TBP) and trioctylphosphine oxide (TOPO). Depending on these transport parameters were calculated kinetics parameters such as: pseudo-first-order apparent membrane entrance and exit rate constants, the maximum flux at the entrance and exit out of the membrane. The highest values of the transport flux is obtained in the presence of carrier trioctylphosphine oxide (TOPO) at the concentration in the feed phase of 10-4 mol/L indole-3-acetic acid and a concentration of 10--2mol/L NaOH in the stripping phase.


Rumen ciliates still have mysterious secrets and influences in ruminants. This study investigated the effect of transfaunation of pure and mixed cultures of rumen ciliates on physical clinical examination, selected serum parameters and milk profile in defaunated lactating dairy goats. A number of 8 Baladi native breed goats were randomly classified into two groups each one containing 4 goats. Pure culture group was transfaunated with 6 ml of pure culture of Holotricha spp., while mixed culture group was transfaunated with 6 ml of mixed culture of 81.85% Holotricha and 18.15% Ophryoscolex spp. once weekly for three consecutive weeks, after defaunation of both groups using 30 ml of 8% SLS for two consecutive days. Serum and milk samples were collected weekly for three successive weeks to study effect of type of ciliate culture, duration of transfaunation and their interaction. Results revealed that transfaunation of pure and mixed cultures of rumen ciliates had no effect on physical examination with minimal non-significant improvement of calcium, inorganic phosphorous, total protein and globulin in serum of defaunated goats. Transfaunation of pure or mixed cultures of rumen ciliates within three weeks could not improve significantly decreased milk fat % of defaunated goats without any effect on other measured milk profile parameters. It is concluded that further investigations on transfaunation without prior defaunation should be performed using different pure and mixed cultures of rumen ciliates for therapeutic and productive purposes.


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