Incubation medium, composition

The classical Chinese method consists of inoculating steamed rice grains spread on big trays with a strain of Monascus anka and incubating in an aerated and temperature-controlled room for 20 days. In these types of cultures, moisture content, oxygen, and carbon dioxide levels in the gas environment, as well as cereal medium composition, are the most important parameters to conhol. 

A. Chaboud and M. Rougier, Effect of root density in incubation medium on root exudate composition of axenic maize seedlings, J. Plant Physiol. 131 602 (1991). 

Biologic effects of non-excited fullerenes C60, that are revealed at the concentration range lower than 10 4 M, are mostly positive, but depend on the type of cells and the way of modification of fullerene C60 (Yamakoshi et al., 1994). As we have shown earlier, upon the presence of 10 6 M fullerenes C60 in incubation medium, resistance of erythrocytes to hemolysis is not altered, whilst at the concentration of 10 5 M fullerenes C60 the hemolysis rate is accelerated. Hemolytic effect was not revealed if fullerene C. at the concentration of 10 5 M was introduced to the con-tent of aminopropylaerosyl (i.e., upon the presence of fullerene C60-composite-l). Cytotoxic influence was not found if thymocytes and EAC cells were incubated with fullerenes C60 (10 5 M) or fullerene C60-containing composites for 24 h (Piylutska et al., 2006). That is why the study of the influence of irradiation on biologic activity of fullerenes C60 was carried out at their concentration of 10 5 M. 

In the case of photoexcited fullerenes C60 and fullerene C60-containing composites in incubation medium of thymocytes, the indexes of LPO did not alter compared to the control too (Fig. 6.2A). Upon incubation of EAC cells in the presence of photoexcited samples of fullerenes, the decrease in the content of diene conjugates by 35% in the presence of fullerene C60 and by 20% in the presence of fullerene C60-composite-1 and fullerene C60-composite-2 was observed (Fig. 6.2B). The presence of photoexcited samples of fullerenes in the suspension of L1210 cells influenced LPO indexes only in the presence of fullerene C60-composite-2, when the content of diene conjugates increased by 35% (Fig 6.2C). 

Changes in the composition of the slices and/or incubation medium give some indication of metabolic activity, but extensive damage may be caused to the cells on slicing the system is so artificial that data obtained by the tissue slice technique may not pertain to the physiological situation. However, the technique is widely used at least for introductory, exploratory experiments. 

After preincubation of the brush border membrane vesicle preparation for 2 h, [2 14 C]urate uptake is initiated by adding 200 pi of incubation medium to 20 pi of the membrane suspension. The incubation medium has the following composition (mmol/1) 150 mannitol, 2 MgS04, 50 potassium phosphate buffer, pH 6.0 or 7.5, 0.02 [2-14 C]urate, and various concentrations of the inhibitor. At 10 s after the addition of the incubation medium, 200 pi portions of the suspension are pipetted onto the center of prewetted cellulose acetate filters kept under suction. The vesicles retaining on the filter are washed immediately with 5 ml of an ice-cold solution containing 150 mmol/1 mannitol and 50 mmol/1 potassium phosphate buffer, pH 6.0 or 7.5, which is used at the same pH as the incubation medium. Preincubations and incubations are performed at 23 1 °C. Each experiment is performed in triplicate. Corrections are made for the radioactivity bound to the filters in the absence of membrane vesicles. The term of the OH gradient-dependent urate uptake is defined as the difference between the uptakes in the incubation medium at pH 6.0 and that at pH 7.5. The OII gradient-dependent urate uptake at 10 s is assumed to present an initial velocity. 

The implication of such stimuli-responsive particles as a solid polymer support of biomolecules in the biomedical field is probably due to various factors (1) easiest to prepare via precipitation polymerization (hydrogel particles) or a combination of emulsion and precipitation polymerizations (core-shell particles), (2) the colloidal properties are related to the temperature and to the medium composition (i.e., pH, salinity, surfactant etc.), (3) the adsorption and the desorption of antibodies and proteins are principally related to the incubation temperature, (4) the covalent binding of proteins onto such hydrophilic and stimuli-responsive particles can be controlled easily by temperature, and, finally, (5) the hydrophilic character of the microgel particles is an undeniably suitable environment for immobilized biomolecules. 

Nonspecific interference can be encountered as a result of changes in temperature, ionic strength, and pH, or as a result of the presence of hemolysis or excessive quantities of bilirubin, heparin, and urea. Any of these factors can alter the composition of the incubation medium and affect the kinetics or equilibrium of the antigen-antibody reaction. Nonspecific interference contributes to assay variability and results in a decrease in sensitivity. This is particularly prevalent in early enzyme IA applications. Assay sensitivity can be greatly improved with increased assay specificity. 

Cell-free system. The first experiment with cell-free systems containing labeled nuclei and nonlabeled cytoplasm (Schneider, 1959 Scholtissek and Potter, 1960) indicated the removal of newly formed RNA from the nuclei during the incubation. The newly synthesized RNA was found in the incubation medium in particles with different sedimentation coefficients. These results have been confirmed by others (Samarina and Zbarsky, 1964 Ishikawa et al., 1969 Lukanidin, 1969). Sometimes ATP and other donors of energy enhance the loss of RNA from nuclei (Ishikawa et al., 1969). However, this process seems not to differ from the simple extraction of D-RNP from nuclei and thus may not be a model of transport. Lukanidin (1969) analyzed the particles in a CsCl density gradient and found that almost all labeled material leaving the nucleus has a buoyant density of 1.40 g/cm and does not interact with the cytoplasmic ribosomes which band at p = 1.55 to 1.58 g/cm. Only a small amount of labeled material banded in the intermediate zone, but it had a base composition similar to rRNA and thus may represent the ribosomal RNA precursors. The addition to the system of a variety of factors necessary for protein synthesis did not influence the results. 

Poulin P, Haddad S. 2013. Hepatocyte composition-based model as a mechanistic tool for predicting the cell medium partition coefficients of drugs in incubation mediums. J Pharm Sci 102 2806-2818. 

R. eutropha cells were grown in a nutrient-rich medium for 24 h and then transferred to a nitrogen-free medium containing the above carbon sources PHA content in cells incubated for 48 h in nitrogen-free medium Composition determined by H-nuclear magnetic resonance (NMR)... 

From the initial reliance on conventional bacterial cultures, research has progressed to a consideration of growth conditions (medium composition, incubation temperature/time) and the precise antigenic composition of the bacterial cells. A topical example concerns A. salmonicida, which, when cultured in iron-depleted conditions, produces highly immunogenic iron regulated outer membrane proteins (IROMP) (e.g. Durbin et al., 1999). 

Sterile agar slants are prepared using the Streptomyces sporulation medium of Hickey and Tresner, J. Bact., vol. 64, pages 891-892 (1952). Four of these slants are inoculated with lyophilized spores of Streptomyces antibioticus NRRL 3238, incubated at 28°C for 7 days or until aerial spore growth is well-advanced, and then stored at 5°C. The spores from the four slants are suspended in 40 ml of 0.1% sterile sodium heptadecyl sulfate solution. A nutrient medium having the following composition is then prepared 2.0% glucose monohydrate 1.0% soybean meal, solvent extracted, 44% protein 0.5% animal peptone (Wilson s protopeptone 159) 0.2% ammonium chloride 0.5% sodium chloride 0.25% calcium carbonate and water to make 100%. 

The shape of an organism may also vary depending upon certain environmental factors, such as temperature of incubation, age of the culture, concentration of the substrate, and composition of the medium. Bacteria usually exhibit their characteristic morphology in young cultures and on media possessing favorable conditions for growth. 

An important question arises about the effects of phospholipid composition and the function of membrane-bound enzymes. The phospholipid composition and cholesterol content in cell membranes of cultured cells can be modified, either by supplementing the medium with specific lipids or by incubation with different types of liposomes. Direct effects of phospholipid structure have been observed on the activity of the Ca2+-ATPase (due to changes in the phosphorylation and nucleotide binding domains) [37]. Evidence of a relationship between lipid structure and membrane functions also comes from studies with the insulin receptor [38]. Lipid alteration had no influence on insulin binding, but modified the kinetics of receptor autophosphorylation. 

In the subsurface, kerosene volatilization is controlled by the physical and chemical properties of the solid phase and by the water content. Porosity is a major factor in defining the volatilization process. Galin et al. (1990) reported an experiment where neat kerosene at the saturation retention value was recovered from coarse, medium, and fine sands after 1, 5, and 14 days of incubation. The porosity of the sands decreased from coarse to fine. Figure 8.9 presents gas chromatographs obtained after kerosene volatilization. Note the loss of the more volatile hydrocarbons by evaporation in all sands 14 days after application and the lack of resemblance to the original kerosene. It is clear that the pore size of the sands affected the chemical composition of the remaining kerosene. For example, the fractions disap-... 

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