Taurine, extraction

Celluloses (native or microcrystalline) are organic sorbents. They have a low specific surface area and are applied mainly in partition chromatography, especially for the separation of relatively polar compounds. Works on the topic include those by Whitton and coworkers [8], who examined biosynthetic pathways for the formation of taurine in vertebrates. Taurine and its precursor amino acids were extracted from tissues, and the purified supernatant was spotted onto cellulose plates. The... 

Fig. 4. 500 MHz DOSY spectrum of a D2O solution of a perchloric acid extract of gerbil brain. Assignments of selected signals are indicated as follows ac = acetate ala = alanine cho = choline cr = creatine ere = creatinine etn = ethanolamine GABA = 7-aminobutyric acid glu = glutamate GPC = glycerophosphocholine lac = lactate m-ino = myo-inositol NAA = N-acetylaspartate succ = succinate and tau = taurine. (Raw data...

Ion pair extraction has also been used to extract polar analytes in bioanalytical procedures. Figure 15.2 exemplifies the determination of the amino acid taurine by gas chromatography-mass spectrometry (GC-MS) this figure also illustrates a useful property of amines (and phenols), which is that they will react more rapidly than water with an acylating reagent in an aqueous environment thus improving their organosolubility. After acylation and ion pair extraction with tetrabutyl ammonium sulphate the taurine is converted to an amide prior to analysis by GC-MS. 

Human serum sample (0.5 ml), diluted with 2.5 ml of 0.1 N NaOH is incubated at 65°C for 15 min. The free, and glycine- and taurine-conjugated fractions are isolated by means of solid-phase extraction, using BE C18 and BE SAX cartridges in succession [23]. The taurine fraction is enzymatically hydrolysed according to a previously described method [24]. The final residue is treated with 1 ml volume of 0.01% (w/v) KOH methanolic solution (methanokwater 1 9, v/v) at 40°C by ultrasonication for 3 min. Then, 0.2 ml of the obtained suspension is derivatised as described below. BA content is determined in each sample by comparison with an appropriate standard solution. 

GP McMahon, R O Kennedy, MT Kelly. High-performance liquid chromatographic determination of taurine in human plasma using pre-column extraction and derivatization. J Pharm Biomed Anal... 

These products aim primarily to provide a boost to mental energy or buzz . They are marketed as pick-me-ups , and command a high profit margin. An impressive list of ingredients is essential for credibility and typical components include caffeine, taurine, glucuronolactone, inositol, maltodextrin, vitamins and herbal extracts such as guarana, ginseng and schizandra. 

Browning of glucose and simple mixtures of amino acids did not produce authentic meaty aromas, but heating a synthetic mixture of all compounds identified in beef extract in the appropriate concentration, including alanine, glutamic acid, asparagine, taurine, carnosine, anserine, histidine, cystine, creatinine, hypoxanthine, lactic and succinic acid, produced a highly desirable meaty odor. 

It was also sound in a supplementary test that glycine betaine serves to produce a delicate flavor. Proline, taurine, and TMAO, although their concentrations are remarkably high, contribute little to the taste, as do the other minor components. It was thereby confirmed that a synthetic extract containing the above twelve components could reproduce the crab-like taste, although it is weaker than that of the mixture containing all the constituents listed in Table VII. 

A food supplement consisting of oyster extract, ginseng, taurine, and zinc (Ostrin plus GTZ 611) has been associated with Quincke s facial edema. The reaction developed immediately after intake of the food supplement, and the oyster extract was considered to be its most likely cause (36). 

Figure 2 1H NMR data of stage 38 medaka embryo extracts, including (a) 1D spectrum, (b) the 1D skyline projection (p-JRES) of (c) a 2D JRES spectrum, and (d) the preprocessed p-JRES spectrum. Resonances due to citrate (Cit), taurine (Tau), and alanine (Ala) are indicated. Reprinted from M. R. Viant, Biochem. Biophys. Res. Commun. 2003, 310 (3), 943-948. Copyright (2003), with permission from Elsevier.

Fig. 6.22. The (a) 1-D and (b) 2-D-DOSY spectrum of a mixture containing D2O, glucose, ATP and SDS micelles [50]. (Adapted with permission from ref. [50]. Copyright 1993 American Chemical Society), (c) 1-D and (d) 2D-DOSY spectrum of the perchloric acid extract of a gerbil brain in D2O. Selected assignments are ac — acetate ala — alanine cho — choline cr — creatinine etn — ethanolamine GABA — y-aminobutyric acid glu — glutamine CPC — glycerophospho-choline lac — lactate m-ino — myo-inositol NAA — N-acetylaspartate succ — succinate and tau = taurine [51]. (Adapted with permission from ref. [51]. Copyright 1997 Elsevier.)...

For the quantitative estimation of bile acids in body fluids and tissues, consideration must be given as to whether (1) an extraction step is necessary to partially purify the bile acids prior to further analysis (2) hydrolysis is required to remove glycine and taurine or other conjugate moieties and (3) the method of analysis will be of the required sensitivity and provide infer-... 

Unlike enzymatic or radioimmunoassay methods, GLC requires lengthy sample preparation before bile acid concentrations can be determined. In the case of serum, bile acids must be extracted (see Section 6.1) and hydrolysis carried out to remove glycine and taurine, and also sul te groups, if they are likely to be present (see Section 6.2). The free bile acids are then converted to volatile derivatives. 

E.I. Pentz, Liquid—liquid extraction in the autoanalyzer. Determination of taurine, Anal. Biochem. 8 (1964) 328. 

Bacterial extracts from sewage mud containing bacteria which can grow on taurine as the sole source of carbon, nitrogen and sulphur were found165 to form sulphoacetal-dehyde, 200. 

Shirley, M.A. Guan, X. Kaiser, D.G. Halstead, G.W. Baillie, TA. Taurine conjugation of ibuprofen in humans and in rat liver in vitro. Relationship to metabolic chiral inversion. J.PharmacoLExp.Ther., 1994, 269, 1166-1175 [human urine gradient extracted metabolites microsomal incubations rat liver]... 

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