Aspartame, applications

This technique has been established for many years particularly for water, soil and feeding-stuff analysis, where a large number of analyses are required for quality control or monitoring purposes. A number of applications have been published for food additives including aspartame (Fatibello et al., 1999), citric acid (Prodromidis et al., 1997), chloride, nitrite and nitrate (Ferreira et al., 1996), cyclamates (Cabero et al., 1999), sulphites (Huang et al., 1999 AOAC Int, 2000), and carbonate, sulphite and acetate (Shi et al., 1996). Yebra-Biumm (2000) reviewed the determination of artificial sweeteners (saccharin, aspartame and cyclamate) by flow injection. 

Abstract Aspartame (Apt), Acesulfame-K (Ace-K) low-calorie, high-potency artificial sweeteners ate cnnently nsed in beverages and dietary food and drinks. Their increased application in food and drink prodncts has given a new impetus to develop fast and accurate methods for their determination. Absorption spectra of Asp, Caf, Ace-K and BA strongly overlap. Therefore a direct determination of these analytes in quaternary mixture is impossible without a separation step. In order to overcome this difficulty partial least squares (PLS) method has been proposed. 

CE has been applied extensively for the separation of chiral compounds in chemical and pharmaceutical analysis.First chiral separations were reported by Gozel et al. who separated the enantiomers of some dansylated amino acids by using diastereomeric complex formation with Cu " -aspartame. Later, Tran et al. demonstrated that such a separation was also possible by derivatization of amino acids with L-Marfey s reagent. Nishi et al. were able to separate some chiral pharmaceutical compounds by using bile salts as chiral selectors and as micellar surfactants. However, it was not until Fanali first showed the utilization of cyclodextrins as chiral selectors that a boom in the number of applications was noted. Cyclodextrins are added to the buffer electrolyte and a chiral recognition may... 

Application of Acidulant product and component of aspartame Antibiotic component Chiral intermediate Food/feed additive Herbicic... 

The sweetness of fmctose is enhanced by syneigistic combinations with sucrose (12) and high intensity sweeteners (13), eg, aspartame, saccharin, acesulfame K, and sucralose. Information on food application is available (14,15). Fmctose also reduces the starch gelatinization temperature relative to sucrose in baking applications (16—18). 

Arylation, olefins, 187, 190 Arylketimines, iridium hydrogenation, 83 Arylpropanoic acid, Grignard coupling, 190 Aspartame, 8, 27 Asymmetric catalysis characteristics, 11 chiral metal complexes, 122 covalently bound intermediates, 323 electrochemistry, 342 hydrogen-bonded associates, 328 industrial applications, 8, 357 optically active compounds, 2 phase-transfer reactions, 333 photochemistry, 341 polymerization, 174, 332 purely organic compounds, 323 see also specific complexes Asymmetric induction, 71, 155 Attractive interaction, 196, 216 Autoinduction, 330 Axial chirality, 18 Aza-Diels-Alder reaction, 220 Azetidinone, 44, 80 Aziridination, olefins, 207... 

There are numerous further applications for which maleic anhydride serves as a raw material, These applications prove the versatility of this molecule. The popular artificial sweetener aspartame is a dipeplide with one aminnacid ll.-aspartic acid) which is produced from maleic anhydride as the starting material. An important future use lor inalcic anhydride is believed In he the production of products in the 1.4-biitancdiol-y-hutyrnlacionc-tcnrahydroluran family. This technology can he used to produce ihe product nnx of the three molecules as needed by the- producer. 

Staff Applications of Aspartame in Baking, Food Technology. 56 (January 1988). Staff Evaluation of Advanced Sweeteners, Food Technology, 60 (Januaiy 1988). 

The food industry is a fertile area for biocatalysis applications high-fructose corn syrup (HFCS) from glucose with glucose isomerase, the thermolysin-catalyzed synthesis of the artificial sweetener Aspartame , hydrolysis of lactose for lactose-intolerant consumers, and the synthesis of the nutraceutical i-camitine in a two-enzyme system from "ybutyrobetaine all serve as examples. 

Since MIPs are highly stable and can be sterilised, they are valuable for use in biotransformation processes (Ramstrom and Mosbach, 1999). The application of MIP in catalytic reaction has been demonstrated with reference to the enzymic condensation of Z-L-aspartic acid with L-phenylalanine methyl ester to give Z-aspartame (Ye et al., 1999). In this study, when the product-imprinted polymer was present, a considerable increase (40%) in product yield was found. 

Other important applications in the food industry running at a large scale are the production of L-aspartic add with Escherichia coli entrapped in polyacrilamides [6], the immobilization of thermolysin for the production of aspartame [14], The production of L-alanine by Tanabe Seiyaku [7], the production of frudose concen-centrated syrup [3], the production of L-malic acid by the use of Brevibacterium ammoniagenens immobilized in polyacrilamide by entrapment immobilization methods [11] and L-aminoacids production by immobilized aminoacylase [5],... 

R. Alder and H. P. Merkle, Studies on the stability of aspartame, I specific and reproducible HPLC assay for aspartame and its potential degradation products and applications to acid hydrolysis of aspartame, Pharmazie, 46 91 (1991). 

Ottinger el al.2S6 have applied their comparative taste dilution analysis (cTDA) to examine the extractable products from heated aqueous D-glucose and L-alanine that were not solvent-extractable. One HPLC fraction proved to be a strong sweetness enhancer. It was isolated and submitted to LC-MS and NMR, both ID and 2D the results, together with its synthesis from HMF and alanine, unequivocally identified it as the inner salt of /V-( I -carboxycthyl)-6-(hydroxy-methyl)pyridinium-3-ol (alapyridaine, Structure 45). It has no taste on its own, which in many applications would be an advantage. Depending on the pH, it lowers the detection threshold of sweet sugars, amino acids, and aspartame, the... 

Spot plate B. For aspartic acid, lane (2), and for the hydrolyzed and nonhydrolyzed aspartame, lanes (3) and (5), use one spot as before. For Diet Coke [lanes (1) and (4)] multiple spotting is needed. Apply the capillary tube 12-15 times to the same spot, making certain that between each application the previous sample has been dried. Also, try to control the size of the spots so that they do not spread too much, not more than 2 mm in diameter. Dry the spots as before. Place the plate in a large beaker containing the eluting solvent as before. Cover the beaker with aluminum foil. Allow about 50-60 min. for the solvent front to advance. 

After the finding of a sweet taste in L-Asp-L-Phe-OMe (aspartame) by Mazur et at. (6), a number of aspartyl dipeptide esters were synthesized by several groups in order to deduce structure-taste relationships, and to obtain potent sweet peptides. In the case of the peptides, the configuration and the conformation of the molecule are important in connection with the space-filling properties. The preferred conformations of amino acids can be shown by application of the extended Hiickel theory calculation. However, projection of reasonable conformations for di- and tripeptide molecules is not easily accomplished. 

As mentioned on pages 135 and 136, aspartame might be thought to be too heat sensitive for this application, but in practice this is not so if aspartame is added to the process as late as possible. All other heat sensitive ingredients like flavour, colour and acid have to be added while the mass is still sufficiently warm to be flowable but not too hot to cause decomposition. In results reported in Kennedys Confection, less than 5% of the aspartame was lost upon addition losses of aspartame during storage were found to be equivalent to only a 2% loss of sweetness in a year. Presumably this is because of the low water activity in the finished product. The clean, quickly released sweetness of aspartame works well in these products. 

Acesulfame K is, in contrast, sufficiently heat stable to be added at the beginning of the boil. Unfortunately, the sweetness profile is not as good. One approach to using intense sweeteners is to use a combination of ingredients, and common combinations such as aspartame and acesulfame K or aspartame and saccharin are used. Where they are legal, cyclamates are also used in this application. 

Acesulfame-K is 200 times as sweet as sugar and is not metabolized and is thus noncaloric. It is exceptionally stable at elevated temperatures encountered in baking, and it is also stable in acidic products, such as carbonated soft drinks. It has a synergistic effect when mixed with other low-calorie sweetners, such as aspartame. Common applications of acesulfame-K are table uses, chewing gums, beverages, foods, bakery products, confectionary, oral hygiene products, and pharmaceuticals. 

As with DNA aptamers, there is a trend towards applying RNA aptamers to a particular application. Allosteric ribozyme sensors have been developed which are specific for caffeine and aspartame. " Using a fluorescence-based assay, caffeine or aspartame may be detected in solution over a 0.5 5mM concentration range. Aptamers designed to malachite green (151) or other triphenylmethane dyes have been developed that enhance the fluorescence of the dye up to 2300-fold. " A further fluorescence-based assay has been... 

At the present time, the reported applications of the CR CSP have been limited to the separation of amino acids and some dipeptides as bulk substances. One example of the use of the CR CSP in a complex matrix was the direct stereochemical resolution of aspartame stereoisomers and their degradation products in coffee and diet soft drinks (76). Aspartame (N-DL-a-aspartyl-DL-phenylalanine methyl ester) is a dipeptide whose L,L-isomer is a low-calorie sweetener sold under the name NutraSweet. The structure of aspartame and its major degradation products are presented in Fig. 9 aiwl the stereochemical separation of these compounds on the CR CSP in Fig. lOA. The resolutions were accomplished using a mobile phase... 

The example of an LC chiral separation shown in Figure 12.6 serves to emphasise (a) that the demand for effective chiral selectors is such that even complex synthetic chiral selectors have been commercialised, and (b) the interest in chirality extends beyond pharmaceutical applications, being widespread and in this instance being found in food analysis. Aspartame (N-DL-cx-aspartyl-DL-phenylalanine methyl ester (Figure 12.7)) can exist as four stereoisomers, DD-, LL-, DL- and LD-. On an achiral column DD- and LL- would appear as a single peak which would be separable from another single peak arising from DL- and LD-. A chiral column is needed to separate the enantiomeric pairs (i.e. DD- from LL- and DL-from LD-). The LL-isomer is used as artificial sweetener (under the brand... 

Beck, C.I. Application potential for aspartame in low calorie and dietetic food. In Low Calorie and Dietary Food Dwivedi, B.K., Ed. CRC Press, Inc. Boca Raton, FL, 1978 68. 

The typical level used in foods is 1-5 ppm although much higher levels may be used in certain applications such as chewing gum. Synergistic effects occur with other intense and bulk sweeteners such as acesulfame K, aspartame, polyols, and saccharin. ... 

Go to Appendix C. If you are using a TI-83 Plus, you can download the program PEPTIDE and run the application as directed. If you are using another calculator, your teacher will provide you with keystrokes to use. There are 20 amino acids that occur in proteins found in nature. The program will prompt you to input a number of amino acids. After you do, press ENTER. The program will respond with the number of different straight-chain polypeptides possible given that number of amino acid units, a. Aspartame is an artificial sweetener that is a dipeptide, a protein made of two amino acids. How many possible dipeptides are there ... 

The formation and further transformation of esters belongs to the fundamentals of organic chemistry. Moreover, some esters have enormous importance for example triglycerides (1), in the form of fats and oils, are produced in million ton quantities for a number of applications. Other esters, e.g. (2) and (3), are olifactory components waxes, e.g. (4), are used commercially to protect metallic surfaces against corrosion. Aspartame (5) is an important artificial sweetener, and pyrethrin (6) is the prototype of the pyre-throids, an unusually potent class of insecticides. Apart from these more applied considerations, esters are important synthetic intermediates in a number of multistep sequences. Striking examples are chain elongations via Homer alkenation or a-alkylations of ester enolates, in particular the ones stereocon-trolled by chiral auxiliaries. ... 

The NCA/NTA technology has found application in the synthesis of fragments of ribonuclease A, as well as in the large scale synthesis of ACE inhibitor precursors of enalapriP - and the artificial sweetener aspartam. ... 

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