Shake flasks

We start rxn, one drop / second or so C in B. Sometimes we close sep funnel and shake flask B to ensure a constant rate of MeONO generation. Addition speed is limited by equilibrium of pressure between flasks. If it is too much quick, then MeONO gas go through sep. funnel, then we close the sep funnel and wait a bit till generation is low. The addition of C in B takes 1 hour, we close sep funnel and shake a bit B to finish reaction. If rxn (A) climbs temp too much, we can add ice in the water bath. I ve monitorized temp touching a part of solution that was out of water bath. At the final part may be water is to much cool, so we can take it out. After the addition of C in B we wait one more hour. 

Distribution of benzodiazepines in I-octanol - water system was investigated by a direct shake flask method at the presence of the compounds used in HPLC mobile phases the phosphate buffer with pH 6,87 (substances (I) - (II)), acetic and phosphate buffer, perchloric acid at pH 3 (substances (III) - (VI)). Concentrations of substances in an aqueous phase after distribution controlled by HPLC (chromatograph Hewlett Packard, column Nucleosil 100-5 C, mobile phase acetonitrile - phosphate buffer solution with pH 2,5, 30 70 (v/v)). 

A substitute may be prepared thus 0 05 gram palladous chloride is placed in a special shaking flask with 50 c.c, of 50 per cent, alcohol and 1 or 2 c c. of 1 per cent, aqueous solution of gum-arabic, the weight of gum being about one-fourth the weight of the palladous chloride. On shaking this mixture in an atmosphere of hydrogen the chloride is reduced with formation of a black solution of colloidal platinum, which is rendered stable by the small quantity of gum present. 

Germination Stage A lyophilized culture of M. purpurea is added to a 300 ml shake flask... 

The resulting culture liquids were utilized for seeding. 20 ml of the medium having the composition described above were poured into a 500 ml shaking flask and sterilized at 115°C for 10 minutes and five drops of the above seed were added, and then cultured with shaking at 30°C for 65 hours. Thereafter 0.15 g/dl of inosine were accumulated. 

As described in U.S. Patent 2,931,798, Streptomyces kanamyceticus (K2-J) was first cultured in shake flasks in the following media (a) 0.75% meat extract, 0.75% peptone,... 

Tank fermentation of Micromonospora inyoensis — Germination stage 1 Under aseptic conditions, add a lyophilized culture (or cells obtained from a slant culture) of M. inyoensis to a 300 ml shake flask containing 100 ml of the following sterile medium ... 

Once methanol-using organisms had been isolated they were screened in small-volume shake-flask cultures to determine their ability to grow in methanol-minimal-medium (such as Medium B described in the previous section) to produce high yields at high growth rates. Optimum growth temperatures and pHs were also determined. 

A 3 litre bioreactor with a working volume of 2 litre is inoculated with the three shaking flasks. The pH is maintained at 5.5 by automatic titration with 5mol l 1 NH4OH and the temperature is held at 37°C. 

The temperature optima of isolated organisms would be measured early on in development, usually in shake-flask culture. 

A shake-flask broth was filtered with a filtration unit and all the process conditions and variables are defined in the following table. 

Cripe CR, Walker WW, Pritchard PH, et al. 1987. A shake-flask test for estimation of biodegradability of toxic organic substances in the aquatic environment. Ecotoxicol Environ Safety 14 239-251. 

The main part of the report describes the results of systematic investigations into the hydrodynamic stress on particles in stirred tanks, reactors with dominating boundary-layer flow, shake flasks, viscosimeters, bubble columns and gas-operated loop reactors. These results for model and biological particle systems permit fundamental conclusions on particle stress and the dimensions and selection of suitable bioreactors according to the criterion of particle stress. 

Special reactors are required to conduct biochemical reactions for the transformation and production of chemical and biological substances involving the use of biocatalysts (enzymes, immobilised enzymes, microorganisms, plant and animal cells). These bioreactors have to be designed so that the enzymes or living organisms can be used under defined, optimal conditions. The bioreactors which are mainly used on laboratory scale and industrially are roller bottles, shake flasks, stirred tanks and bubble columns (see Table 1). 

Whereas roller bottles and shake flasks are used for screening tests or for the cultivation of precultures, on production scale mainly stirred tanks, bubble columns, and in a few cases, also loop reactors are used (see Table 5). The stress in these reactors is therefore also of special significance and should be given particular consideration. 

In shake flasks there is neither undisturbed laminar flow nor fully developed turbulent flow. However, stress can be estimated approximately using Eqs. (2-4). 

There is only very few process design literature for the calculation of power input for shake flasks [14-17]. Only the recent publication of Biichs et al. [17] provides a suitable correlation for the operating and geometric conditions... 

This correlation was obtained as a result of extensive measurements with shake flasks of volume = 100-2000 ml and corresponding inner diameter dg= 6.1-16 cm, a filled volume ofVL= (0.04-0.2)V, and eccentricity of shaking machine of 25 and 50 mm. 

Zoels [19] provides some results for shake flasks with baffles, which according to Henzler, Schedel [18] are not a better alternative than systems without reinforcement. 

No details of energy distribution in shake flasks based on flow measurement are known to date. 

As is the case with pure bubble columns and gas-operated loop reactors, most bioreactors in technical use are aerated with oxygen or air. Reactors with pure surface aeration, such as roller bottles, shake flasks and small stirred reactors or special reactors with membrane aeration, are exceptions. The latter are used for the cultivation of cells and organisms which are particularly sensitive to shearing (see e. g. [28 - 29]). The influence of gas bubbles in increasing stress has been described in many publications (see e.g. [4, 27, 29, 30]). In principle it can be caused by the following processes ... 

The presented results for systematic studies on hydrodynamic stress in shake flasks, baffled stirred tanks, reactors in which boundary layer flow predominates (e.g. stirred tank with a smooth disc or unbaffled stirred tank), viscosi-... 

For plant cell suspensions cultivated in shake flasks, Huang et al. [45] used the energy dissipation rate as a correlating parameter for system response. Specific power input was calculated using the empirical correlation proposed by Sumino et al. [46] and subsequently employed in other applications [47,48] ... 

Table 3. Shear studies (post-1993) involving plant cell suspensions in STR or shake flask systems. Studies prior to 1993 are summarized by Meijer et al. [1993]... 

Stizolobium hassjoo 125-ml shake flasks 140-220 rpm (0.4-1.7 m s- ) secondary metabolite production aggregate size [45]... 

Solanum aviculare 250-ml shake flasks 100 - 600 rpm (3.5 cm throw) t 10 d cellular DNA distribution (flow cytometry) [110]... 

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