Optimization, extraction

The most active extracts were obtained8 from L. mesenteroides cultures containing sucrose extracts prepared from L. mesenteroides organisms repeatedly transferred through D-glucose broth were of low potency.48 Active extracts in dilutions of 1 2 or 1 4 produced dextran in 5% sucrose solutions after one to two hours at 23°, and at pH 5.6 with acetate buffer demonstrable amounts of dextran were produced after twenty days with 1/10,000 dilution of the extract. Optimal yields of dextran were less than 5% based on sucrose. Small concentrations of dextran were detected by means of precipitin titrations with pneumococcus antisera Types II or XX (see page 215). 

In the early analytical applications of solvent extraction, optimal extraction or separation conditions were obtained empirically. This was unsatisfactory and general mathematical descriptions were developed by a number of researchers in many countries. This was especially important for large-scale industrial use and is an activity that continues today almost entirely with computers. 

Modolo, G., Asp, H., Schreinemachers, C., Vijgen, H. 2007. Development of a TODGA based process for partitioning of actinides from a PUREX raffinate Part I Batch extraction optimization studies and stability tests. Solvent Extr. Ion Exch. 25 (6) 703-721. 

The solubilities of S-diketonate complexes of Cu, Zn, Ni and Co in supercritical CO2 were determined. A linear correlation was found between the stability of the metal complex and extractant dissociation. This correlation helps finding extractants optimized for both extraction of metals and the recovery of valuble chemicals. Supercritical CO2 best extracted Cu S-diketonates and the free metal could be best recovered in nitric acid. The other metal complexes showed lower extraction levels in the decreasing order of Ni, Co and Zn. The metal removal efficiency from the stripping solution into CO2 varied between 5 and 90% and decreased in the order Cu, Co, Ni and Zn. The overall... 

Cho, S. M., Gu, Y. S., and Kim, S. B. (2005). Extracting optimization and physical properties of yellowfin tuna (Thunnus albacares) skin gelatin compared to mammalian gelatins. Food Hydrocolloids 19, 221-229. 

Altaf, M., Naveena, B.J., Venkateshwar, M., Kumar, E.V., and Reddy, G. 2006. Single step fermentation of starch to 1(+) lactic acid by Lactobacillus amylophi-lus GV6 in SSF using inexpensive nitrogen sources to replace peptone and yeast extract—Optimization by RSM. Proceedings in Biochemistry 41 465-472. 

Extraction Optimization in Food Engineering, edited by Constantina Tzia and George Liadakis... 

Oreopoulou, V., Extraction of natural antioxidants, in Extraction Optimization in Food Engineering, Tzia, C. and Liadiakis, G. (Eds.), Marcel Dekker, New York, pp. 329-346, 2003. 

Being the three-parameter model, the Toth equation can describe well many adsorption data. We apply this isotherm equation to fit the isotherm data of propane on activated carbon. For example taking the isotherm data at 303 K in Table 3.2-1, the extracted optimal parameters are (using the ISO FITl routine) ... 

Heck JX, Hertz PF, Ayub MAZ. (2005b). Extraction optimization of xylanases obtained by solid-state cultivation of Bacillus circulans BL53. Process Biochem, 40, 2891-2895. 

Aguilera JM (2003) Solid-liquid extractirai. In Liadalds G, Tzia C (eds) Extraction optimization in food engineering. CRC, New York... 

Fluid flow rate is also considered in extraction optimization. It is usually used to determine whether the extraction is solubility or internal diffusion controlled. Typically, solubility controlled extractions show a direct correlation to the flow rate, whereas internal diffusion controlled extractions show this much less. In internal diffusion-controlled processes, the extraction yield can be increased by using smaller particles, as the specific area increases and the internal diffusion resistance lessens, due to a shorter diffusion path (Snyder et al., 1984). However, this is not always the case, as smaller particles may cause channeling (Eggers, 1996). 

Extraction optimization salt addition, extraction time, and desorp. temp Method tested in different matrices surface, tap, and mineral waters LCDs 14 ppt... 

Extraction optimization stirring rate, salt addition, extraction time and temp, desorp. time and temperature, fiber position in the injector HS-SPME ... 

Extraction optimization extraction mode, salt addition, extraction temp., sample volume, and extraction time LODs range from 0.022 to 0.16 ng/L Linear range from 0.1,0.2, or 0.5 to 100 ng/L r > 0.9987... 

Extraction optimization solvent, extraction time, salt concentration, sample and microdrop volumes, stirring rate, sample and microsyringe needle temperature LODs 0.06 pg/L Calibration range 0.1-500 pg/L r = 0.999... 

Extraction optimization extraction time, [213] extraction temp., stirring rate, ionic strength, concentration of reagents, and drop volume LODs ranged from 2.5 to 25 pg/L ranged from 0.9123 to 0.9418 RSD ranged from 6.0% to 12%... 

Extraction optimization sampling volume, solvent volume, sample temp., syringe punger withdrawal rate, and ionic strength LODs ranged from 1 to 97 pg/L (GC-MS scan mode) ranged from 0.9723 to 0.9999 RSD ranged from 5.5% to 9.3% (except for methanol 16.4%)... 

Extraction optimization (one-at-the-time) solvent selection, drop volume, extraction temp., stirring rate, ionic strength, sample volume, and extraction time LODs 0.8 pg/L > 0.998 RSD < 5%... 

Extraction optimization headspace volume, extraction time, stirring rate, salt addition, and extraction temperature... 

Audio extract optimization can be left at Full unless you are experiencing problems with the. wav files ripped from your CDs. CD tracks can be ripped by selecting Extract Audio from CD from the Tools menu. 

Figure 1 presents the results of extraction optimization studies. It is known that fipronil is thermally labile, and thus, only extraction temperatures below 120 °C were investigated. Trials were run at 25, 50, 70, and 120 C, with 1 or 2 extraction cycles that were 5 min for each cycle. The interest was to find a suitable condition for extraction of all four compounds simultaneously by one extraction procedure. Reproducibility of the extractions was good for all conditions examined. The standard deviations for the percentage of recoveries ranged from 2.0 for metabolite C at 70 C and 1 cycle, to 12.2 for metabolite A at the same conditions. 

FIGURE 4.3 Commercial canola processing. (From Xu, L. and Diosady, L. L. 2003. Extraction Optimization in Food Engineering. Marcel Dekker, Inc., New York, New York, pp. 181. With permission.)... 

Licence, R, Ke, J., Sokolova, M., Ross, S.K. and Pobakoff, M. 2003. Chemical reactions in supercritical carbon dioxide From laboratory to commercial plant. Green Chem. 5 99-104. List, G., King, J. and Dunford, N.T. 2003. Supercritical fluid extraction in food engineering, in Extraction Optimization in Food Engineering, C. Zia and G. Liadaku, eds. CRC Press, 2003. 

Dunford NT, King JW, list GR. 2003. Supercritictil Fluid Extraction in Food Engineering. In Tzia, C. and liadalds, G. (editors). Extraction Optimization in Food Engineering. NY Marcel Dekker, Inc. pp. 57-93. 

The optimal extraction eonditions aceording to Golmakani et al. study were as follows 180 C, 207 bar, 15 min and eflianol + ethyl lactate (50 50 v/v) in the case of PLE, predicting 21.5% of total yield and 63.9% of GLnA recovery. For GXLs extraction optimal extraction conditions were 40"C, 300 bar, 90 min and C02/ethanol with 50% ethanol, and the predicted results were 7.0% of total yield and 28.0% of GLnA recovery. These results were experimentally eorroborated (at least three times) by the authors and the prediction was pretty close to the mean real extraction process. Therefore, different extraction alternatives using ethyl lactate as alternative solvent were successfully applied to produce enriched fractions in y-linolenic acid. 

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