Nutrasweet - Aspartame

Aspartame is an artificial sweetener sold under the trade name NutraSweet. Aspartame is the methyl ester of a dipeptide formed from L-aspartic acid and L-phenylalanine and can be summarized as Asp-Phe-OCHs. Surprisingly, the analogous ethyl ester (Asp-Phe-OCH2CH3) is not sweet. If either L residue is replaced with its enantiomeric D residue, the resulting compound is bitter instead of sweet. 

FIG. 14 Partial (a) DSC (rate of heat flow as a function of temperature) and (b) DTG curves (dehydration peaks only) showing the difference between commercial (Nutrasweet) aspartame (curves 1) and aspartame recrystallized from water/isooctane/AOT microemulsions (APM ni, curves 2). In diagram (a) the enthalpy changes, AW, associated with dehydration were calculated by integration of the respective peak area. Scanning rate 10°C/ min. (Adapted from Ref. 107.)... 

Examine the structures oisucrose, the natural sweetener, and saccharin, sodium cyclamate and aspartame (Nutrasweet), three of the most common artificial sweeteners. What, if any, structural features do these molecules have in common Compare electrostatic potential maps for the different sweeteners. Are there any significant features in common Based on yom findings, do you think it is likely that entirely different artifical sweeteners might be discovered Explain. 

F.4 What is the mass percentage composition of aspartame, CI4H 8N205, an artificial sweetener sold as NutraSweet ... 

C13-0115. The artificial sweetener aspartame (NutraSweet) is Ihe methyl ester of Ihe following dipeptide ... 

Aspartame, a dipeptide (aspartic acid + phenylalanine) artificial sweetener marketed under the trade name Nutrasweet... 

Aspartame, N-a-L-aspartyl-L-phenylalanine methyl ester, trade names NutraSweet , and Aspartil , is a dipeptide derivative. Like dipeptides aspartame is metabolised into the constituents, i.e. amino acids and methanol. Therefore studies into the metabolic behaviour and the fate of metabolites were carried out. Levels of blood aspartate and glutamate were measured after intake of high aspartame doses. Changes were transient and allegations of influences of high aspartame levels on brain function could never be verified. 

The profit potential of aspartame was a major factor in the takeover of Searle by Monsanto. (Current aspartame sales are ca. 10 ton/a, equivalent to ca. 850 x lO /a). The success of the Nutrasweet Co. in establishing aspartame in the market. This has... 

Regulatory approval for aspartame produced by Nutrasweet was very long and expensive, although this was no longer such a big problem for Holland Sweetener Co. 

In the future aspartame can expect to encounter competition from new high intensity sweeteners such as sucralose which is produced by Tate Lyle/Johnson Johnson and alitame (Pfizer), which have advantages such as even higher sweetness and, in the case of sucralose, heat stability. In response Nutrasweet are busy developing a new very high intensity sweetener (Sweetener 2000), which is reputed to be 10,000 times as sweet as sucrose. 

Demand for L-phenylalanine was exclnsively from the Monsanto-Ajinomoto joint-venture Nutrasweet Company (the first manufacturer of aspartame). 

Aspartame. Aspartame [22839-47-0] [53906-69-1] (APM, L-aspartyl-L-phenylalanine methyl ester) (1), also known under the trade names of NutraSweet and EQUAL, is the most widely used nonnutritive sweetener worldwide. This dipeptide ester was synthesized as an intermediate for an antiulcer peptide at G. D. Searle in 1965. Although this compound was known in the literature, its sweet taste was serendipitously discovered when a chemist licked his finger which was contaminated with it. Many analogues, especially the more stable esters, were made (6) and their taste qualities and potencies determined. It was the first compound to be chosen for commercial development. Following the purchase of G. D. Searle by Monsanto, the aspartame business was split off to become a separate Monsanto subsidiary called the NutraSweet Company. 

FIGURE 1-23 Stereoisomers distinguishable by smell and taste in humans, (a) Two stereoisomers of carvone R) carvone (isolated from spearmint oil) has the characteristic fragrance of spearmint (S)-carvone (from caraway seed oil) smells like caraway, (b) Aspartame, the artificial sweetener sold under the trade name NutraSweet, is easily distinguishable by taste receptors from its bitter-tasting stereoisomer, although the two differ only in the configuration at one of the two chiral carbon atoms. 

No generalizations can be made about the molecular weights of biologically active peptides and proteins in relation to their functions. Naturally occurring peptides range in length from two to many thousands of amino acid residues. Even the smallest peptides can have biologically important effects. Consider the commercially synthesized dipeptide L-aspartyl-L-phenylalanine methyl ester, the artificial sweetener better known as aspartame or NutraSweet. 

Aspartame came on market sold by G.D. Searle as Nutrasweet . 

Aspartame is an intense sweetener first discovered in 1965 by J. Schlatter it is available under the brand names of Nutrasweet , Equal , and Canderel . Chemically, aspartame is N-L-a-aspartyl-L-phenylalanine methyl ester (Fig. 1), withamolecularformulaofC14H 805N2 (MW = 294.30). It is a white, odorless, crystalline powder. It is slightly soluble in water and sparingly soluble in alcohol. The solubility increases as the pH is lowered (2,6,57). It has 100-200 times the sweetness of sucrose and exhibits a sweet, clean taste and a sweetness profile similar to that of sucrose, without bitter or metallic aftertaste (Table 1). However, it displays a slow onset of sweetness coupled with lingering sweet taste. It extends and intensifies tastes and enhances fruit flavors. Aspartame exhibits synergism, a superior taste profile, and improved stability when used with other sweeteners (1,4,14,55,75). 

Neotame is an amino acid derivative and is, therefore, hydrolysed under conditions of low or high pH. Its stability will be a function of pH, temperature and time. The optimum pH range is similar to that for aspartame pH 3.2 1.5. In dry form neotame is stable. Products containing neotame and processed by high-temperature short-time (HTST) do not show significant losses to degradation of neotame (The NutraSweet Company, 2003). 

The following structure is a computer-drawn representation of aspartame, C HjglS Os, known commercially as NutraSweet. Only the connections between atoms are shown multiple bonds are not indicated. Complete the structure by indicating the positions of the multiple bonds. 

Aspartyl phenylalanine-l-methyl ester, better known as aspartame, is an artificial sweetener with a worldwide production exceeding 15 000 tpa. It is marketed under the trade names Nutrasweet, Canderel, and Equal. This dipeptide, made of aspartic... 

Both benzyl and Cbz groups are used in a synthesis of aspartame 38, the dipeptide that is 150 times sweeter than sugar and used in many soft drinks under the name Nutrasweet . Only one disconnection is reasonable the amide bond in the middle of the molecule suggesting derivatives of available aspartic acid 39 and phenylalanine 40 as starting materials. 

The sweetener aspartame was discovered in 1965 and approved by the FDA in 1981. It is the methyl ester of a dipeptide formed from the amino acids aspartic acid and phenylalanine. Because both of these amino acids occur naturally and arc part of nearly every protein, there is much less reason to be concerned about the health effects of this compound. Nevertheless, it has been extensively tested. Aspartame is about 180 times sweeter than sucrose, so the amount that is needed to sweeten a can of a soft drink, for example, is so small that it contributes only negligible calories to the diet. In addition, the taste profile of aspartame is much closer to sugar than is that of saccharin. Aspartame, sold under the brand name NutraSweet, has been an enormous financial success. Sucralose (Splenda) is prepared from sucrose by replacing some of the hydroxy groups with chlorines. Its taste closely resembles sucrose, but it is about 600 times sweeter. Acesulfame K (Sunett, Sweet One) is about 200 times sweeter than sucrose. It is quite stable to heat, so it is potentially very useful in baked goods. 

Aspartame (Nutrasweet ) is a remarkably sweet-tasting dipeptide ester. Complete hydrolysis of aspartame gives phenyl alanine, aspartic acid, and methanol. Mild incubation with carboxypeptidase has no effect on aspartame. Treatment of aspartame with phenyl isothiocyanate, followed by mild hydrolysis, gives the phenylthiohydantoin of aspartic acid. 

Proteins are amides they are formed when the carboxylic add group of one amino acid condenses with the amino group of another to form an amide linkage (also known as a peptide bond). One protein molecule can contain hundreds of amide bonds. Aspartame, the artificial sweetener marketed as NutraSweet, on the other hand contains just two amino acids, aspartic acid and phenylalanine, joined through one amide bond. Paracetamol is also an amide. 

---