Craig countercurrent distribution

Gau, W. et ah. Mass spectrometric identification of xanthophyll fatty acid esters from marigold flowers (Tagetes erecta) obtained by high performance liquid chromatography and Craig countercurrent distribution, J. Chromatogr., 262, 277, 1983. 

Find, in a reference book, a description of the Craig countercurrent distribution apparatus and discuss its design as it relates to the description of countercurrent extraction presented in this chapter. 

Craig countercurrent distribution The Craig countercurrent distribution apparatus was used to perform numerous distinct sequen-... 

Martin and Porter (19) described a partition chromatographic procedure and first demonstrated the presence of at least one minor active component in the crystalline enzyme preparation. King and Craig (20) found a solvent system permitting effective countercurrent distribution of ribonuclease, ethanol water ammonium sulfate in the ratios 25.9 -57.6 16.5. The principal component of the Kunitz preparation behaved as an almost ideal solute with a partition ratio of 0.8. Albertsson has provided a liquid polymer countercurrent system based on dextrari and methyl cellulose (21). 

L. C. Craig and D. Craig, Laboratory extraction and countercurrent distribution . 

King Te Piao, and Craig Lyman C., Countercurrent Distribution. 10... 

Polymyxin B sulfate is a nearly odorle.ss. white to buff powder. It is freely soluble in water and slightly soluble in alcohol. Its aqueous solutions are slightly acidic or nearly neutral (pH 5 to 7.5) and. when refrigerated,. stable for at least 6 months. Alkaline. solutions are unstable. Polymyxin B was shown to be a mixture by Haasmann and Craig. who used countercurrent distribution techniques to obtain two fractions that differ in. structure only by one fatty acid component. Polymyxin B, contains ( +)-6-methyloctan-l-... 

Craig, L. C., and O. Post Apparatus for Countercurrent Distribution. Analyt. 

The molecular weight of tyrocidine A was found to be about 1,270 . Total hydrolysis and quantitative amino acid analysis revealed the exact composition . Partial hydrolysis, fractionation of the resulting peptide mixture by countercurrent distribution, ion-exchange chromatography and paper-chromatography, followed by sequential analysis, led Paladini and Craig to the structure of tyrocidine A see Table 1.6). 

The development of the method of countercurrent distribution is largely due to the work of Craig and his associates (see Craig et al., 1949). The method is applicable to the separation of any substances that can be reversibly distributed between two immiscible solvents, and these, of course, include peptides. Several different types of apparatus... 

Craig and his co-worker (Craig, 1944 Craig and Post, 1949) were the originators of the multistage technique of countercurrent distribution. Early reviews have been presented by Hecker (1955) and by Craig and Craig (1956). Morris and Morris (1964) and Fleetwood (1966) have published later reviews. 

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