Shake-flask experiment

Some of the compUcations Usted above could be flagged and, sometimes, remedied in a manual shake-flask experiment, but that is unlikely to be the case in automated shake-vial procedures, especially if performed in a 96-well plate setting. Nevertheless, the demands of modern pharmaceutical discovery operations emphasize high-throughput measurements, low compound consumphon... 

Middle distillate, MDUF Gordona strain CYKS1 5.3 W/O = 9 1, 30°C, shake flask experiments [84]... 

Cellulase Activities and Cellulase Formation Rates (rc) in Shake-Flask Experiments by d 4 of Cultivation... 

Batch fermentations with immobilized cells were carried out both in 500-mL Erlenmeyer flasks and in the 2-L Biostat B from BBInternational. All results are the mean of two duplicate experiments. For the shake-flask experiments, 100 mL of the culture medium supplemented with glucose and xylose or aspen hydrolysates was used. pH corrections were done discontinuously every 10 h. 

T. ferrooxidans, in the laboratory shake-flask experiments and in a two-inch pipeline loop. The results indicate that about 80% pyritic sulfur removal was achieved with 10 to 25% coal/water slurry recirculating at 6 ft/sec. at room temperature in 7 to 12 days. 

Results show that the rates of bacterial desulfurization from coal samples are higher in the pipeline loop under turbulent flow conditions as compared to the shake-flask experiments for particle sizes 43 to 20C im. 

Microbial Procedures. A pure culture of T. ferrooxidans obtained from the American Type Culture Collection (ATCC) was used in this study for the shake-flask experiments and the 2-inch slurry pipe-... 

Shake-Flask Experiments with T ferrooxidans. A limited number of experiments were conducted using T.ferrooxidans to determine the influence of process variables on the rate and extent of pyritic sulfur release from the coal samples in shake-flask experiments using a mechanical shaker. No attempt was made to optimize the mineral salts medium composition since the influence of NtfJ, N/P molar ratio and the nitrogen requirements for the growth of T. ferrooxidans have been thoroughly investigated by other workers (4,7,8,10). A mineral salts medium with the composition described earlier in the Microbial Procedures section was used in all the experiments with T. ferrooxidans. 

About 80% pyritic sulfur removal has been achieved by microbial desulfurization of Illinois 6 and Indiana 3 coals using T. ferrooxidans in laboratory shake-flask experiments and in a two-inch pipeline loop. The 10 to 25 wt% coal/water slurry was recirculated at 6-7 ft/sec for 7 to 12 days at 70-90°F. Results also show that the rates of bacterial desulfurization are higher in the pipeline loop under turbulent flow conditions for particle sizes, 43 to 200/m as compared to the shake-flask experiments. It is visualized that the proposed coal slurry pipelines could be used as biological plug flow reactors under aerobic conditions. The laboratory corrosion studies show that use of a corrosion inhibitor will limit the pipeline corrosion rates to acceptable levels. 

However, related to drug absorption, both classical octanol-water partition coefficients and chromatographic partition coefficients using the different chromatographic scales have shown to be predictive. If the exact octanol-water partitioning behaviour of a solute has to be analysed the reversed phase chromatographic experiments seem to be no substitute for classical shake flask experiments. For comparison... 

The actual in vitro measurements of thermodynamic solubility correspond to the idealized titration regime conditions only to some extent. The closest method seems to be a labor-intensive shake-flask experiment requiring relatively large amounts of a dry crystalline drag and long equilibration times. Moreover, each pH point requires a separate measurement in different buffer. Different buffers usually represent different ionic conditions and may lead to internal inconsistency of the solubility profile thus obtained. The buffer issue deserves an entire subsection of this review and will be discussed later. The real question is whether this investment of resources is worthwhile. The answer depends on who is asking the question. A drag-development... 

In order to determine a partition coefficient, water, n-octanol, and test compound are equilibrated with each other after which the concentration of the test compound in the two phases is determined. The experimental difficulties associated with the formation of microdroplets during the shake-flask experiment can to some degree be overcome in the slow-stirring experiment as water, octanol, and the test compound are equilibrated in a gently stirred reactor. The stirring creates a more or less laminar flow between the octanol and the water, and exchange between the phases is enhanced without microdroplets being formed. 

The rates of biodegradation observed in the shake-flask experiment more closely paralleled those from the in situ experiment than those using the flow-though column system. 

Cultures can be inoculated with a spore suspension, or with a small volume of cellulose culture containing mycelium. Enzyme yields are equal with either inoculum, but the mycelial inoculum usually gives more rapid growth and earlier enzyme development. Spore inoculum is usually more convenient for shake flask experiments. 

Spore inoculum, shake flask experiment, grown 18 days at 29°C. 

Spore inoculum, shake flask experiment, grown 18 days at 29 °C. Heated milled Solka Floe (25 minutes 200°C. ball milled 24 hours). Digested samples treated T. viride cellulase (see text). 

Adaptation of P. stipitis to both liquid hydrolyzate and agar resulted in an increase in sugar consumption and ethanol production in undetoxified acid-pretreated com stover. However, the improvements observed in the fermentation rate were less pronounced at rotation speeds of 150 rpm compared to 100 rpm in shake flask experiments. At less optimal conditions of aeration (100 rpm), adaptation significantly improved fermentation rate. However, at increased aeration rates (150 rpm), the improvements in fermentation because of liquid adaptation were less pronounced. In using P. stipitis for the fermentation of biomass hydrolyzates, adaptation could be used to improve fermentation rate at less aeration rates, but at optimal aeration rates, the benefits of adaptation seems to be less pronounced. 

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