Glycerol isolation

The sugar sulfonic acid is l-0-(6-deoxy-6-sulfo-a-D-glucopyranosyl)-glycerol isolated from a plant sulfolipid.46 The plant sulfolipid... 

Hexadec-cis-l -enyl-sn-glycerol Isol. from pig s heart plasmalogen. Mp 37-39 . [a] 5 2.1 (c, 1 in CHCI3). Acid hydrol. gives Glycerol and Hexadecanal. 

Bultel-Ponce, V., Debitus, C., Blond, A., Cerceau, C., and Guyot, M. (1997) Lutoside an acyl-l-(acyl-6 -marmobiosyl)-3-glycerol isolated... 

P. is always the by-product of - glycerol manufacturing due to self-condensation whereby several glycerol molecules are linked together under elimination of water (etherlinkages). Color problems and the lack of constant quality are, however, the reason not to use this by-product but to make p. in a separate process (alkali-catalyzed condensation of glycerol). Isolation and purification are accomplished by ketal formation with acetone. The properties and uses are similar to glycerol. - . esters of fatty acids find use as emulsifiers in cosmetics and food. Esters of p. with polyhydroxy stearic acid are modern solubilizer in oily components of skin preparations. Lit Ullmann (5.)A12,487... 

When dealing with esters of water-soluble, non steam-volatile, poly-hydric alcohols e.g., ethylene glycol or glycerol), the distillate consists of water only (density 1 00). The water soluble, non-volatile alcohol may be isolated by evaporation of the alkahne solution to a thick syrup on a water bath and extraction of the polyhydric alcohol from the salt with cold ethyl alcohol. 

Enzymes. Invertase (P-fmctofuranosidase) is commercially produced from S. cerevisiae or S. uvarum. The enzyme, a glycoproteia, is not excreted but transported to the cell wall. It is, therefore, isolated by subjecting the cells to autolysis followed by filtration and precipitation with either ethanol or isopropanol. The commercial product is available dry or ia the form of a solutioa containing 50% glycerol as a stabilizer. The maia uses are ia sucrose hydrolysis ia high-test molasses and ia the productioa of cream-ceatered candies. 

Medium Boiling Esters. Esterificatioa of ethyl and propyl alcohols, ethylene glycol, and glycerol with various acids, eg, chloro- or bromoacetic, or pymvic, by the use of a third component such as bensene, toluene, hexane, cyclohexane, or carbon tetrachloride to remove the water produced is quite common. Bensene has been used as a co-solvent ia the preparatioa of methyl pymvate from pymvic acid (101). The preparatioa of ethyl lactate is described as an example of the general procedure (102). A mixture of 1 mol 80% lactic acid and 2.3 mol 95% ethyl alcohol is added to a volume of benzene equal to half that of the alcohol (ca 43 mL), and the resulting mixture is refluxed for several hours. When distilled, the overhead condensate separates iato layers. The lower layer is extracted to recover the benzene and alcohol, and the water is discarded. The upper layer is returned to the column for reflux. After all the water is removed from the reaction mixture, the excess of alcohol and benzene is removed by distillation, and the ester is fractionated to isolate the pure ester. 

Acetonide formation is the most commonly used protection for 1,2- and 1,3-diols. The acetonide has been used extensively in carbohydrate chemistry to mask selectively the hydroxyls of the many different sugars. In preparing ace-tonides of triols, the 1,2-derivative is generally favored over the 1,3-derivative which in turn is favored over the 1,4-derivative, but the extent to which the 1,2-acetonide is favored is dependent upon the structure of the triol. Note that the 1,2-selectivity for the ketal from 3-pentanone is better than that from acetone. Its greater lipophilicity also improves the isolation of the ketals of small alcohols such as glycerol. ... 

Several of the intracellular teichoic acids are polymers of glycerol phosphate or ribitol phosphate. An unusual teichoic acid, composed of d-mannitol phosphate, and with pyruvic acid linked as an acetal to 0-4 and 0-5, has been isolated from Brevibacterium iodinum. ... 

South, Y. and Whittick, H., Introduction to Phycology. Blackwell, New York, 1987. Cheng, J.Y., Don Raul, M., and Antia, N.J., Isolation of an unusually stable cis isomer of alloxanthin from a bleached autolysed culture of Chroomonas salina grown pho-toheterotrophically on glycerol observation on cis trans isomerization of alloxanthin,... 

Lack of repeatability of the results of metabolic studies using laboratory strains that have been maintained by repeated transfer for long periods under nonselective conditions may be encountered. These strains may no longer retain their original metabolic capabilities, and this may be particularly prevalent when the strains carry catabolic plasmids that may have been lost under nonselective conditions. For these reasons, strains should be maintained in the presence of a cryoprotectant such as glycerol at low temperatures (-70°C or in liquid Nj) as soon as possible after isolation. Freeze-drying is also widely adopted, and is recommended. 

A different type of endocannabinoid that is also an arachidonic acid derivative was first isolated from canine gut and identified as 2-arachidonyl glycerol (2-AG) (Fig. 3) (Mechoulam, 1995a). 

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