Aspartame VOLUME

Caffeine, benzoic acid, and aspartame in soft drinks are analyzed by three methods. Using several methods to analyze the same sample provides students with the opportunity to compare results with respect to accuracy, volume of sample required, ease of performance, sample throughput, and detection limit. 

There are thousands of breweries worldwide. However, the number of companies using fermentation to produce therapeutic substances and/or fine chemicals number well over 150, and those that grow microorganisms for food and feed number nearly 100. Lists of representative fermentation products produced commercially and the corresponding companies are available (1). Numerous other companies practice fermentation in some small capacity because it is often the only route to synthesize biochemical intermediates, enzymes, and many fine chemicals used in minor quantities. The large volume of L-phenylalanine is mainly used in the manufacture of the artificial dipeptide sweetener known as aspartame [22389-47-0]. Prior to the early 1980s there was httle demand for L-phenyl alanine, most of which was obtained by extraction from human hair and other nonmicrobiological sources. 

Apart from pharmaceuticals, peptides are also used for diagnostics and vaccines. More than 40 peptides are in commercial use today. A dozen of them is shown in Table 3.1. As shown in column 3 of the table, the number of amino acids that make up a specihc peptide varies widely. At the low end there are dipeptides, like the blockbuster antihypertensive drug enalapril and the artihcial sweetener Aspartame (not shown in the table). In terms of volumes produced, there are by far the most important product group. At the high end there is the anticoagulant Hirudin, which is composed of 65 amino acids. Sales of synthetic peptides are estimated at 4 billion as formulated drugs (resp. 300- 400 million as APIs). 

Due to the great success of aspartame the demand for L-phenylalanine is very big (about 6,000 ton/a currently) and prices have fallen considerably with increased volumes of production. 

An example of a nonoccupational exposure is methanol, which is formed endogenously, probably as the result of the activities of intestinal flora or enzymatic processes. It is present in a number of consumer products. Methanol may be present in low concentrations in some foods, juices, and alcoholic beverages. Methanol can also be derived from the intestinal enzymatic hydrolysis of the artificial sweetener aspartame, which results in methanol absorption from the intestine (Butchko et al. 2002). It is estimated that a 355-mL serving of aspartame-sweetened beverages and of various fruit and tomato juices may contribute about 20-100 mg of dietary methanol (Butchko et al. 2002). For comparison purposes, exposure at the current Threshold Limit Value time-weighted average of methanol (262 mg/m3) would result in a daily dose of about 1,500 mg, assuming an 8-hour inhaled volume of 10 m3 of air and absorption of 57%. 

Procedure The assay is performed by separately injecting equal volumes (about 20 pL) of the Standard Solution and the Test Solution into the chromatograph, recording the chromatograms, and measuring the responses for the major peaks. The percentage of aspartame related compound A in the test article is calculated using ... 

L-Aspartic acid (12) is an industrially important, large volume, chiral compound. The primary use of aspartic acid in the fine chemical arena is in the production of aspartame, a high potency sweetener (Chapter 31). Other uses of L-aspartate include dietary supplements, pharmaceuticals, production of alanine (by decarboxylation), antibacterial agents, and lubricating compounds. There have been a number of reviews on L-aspartate production.53 56... 

The market volume of L-phenylalanine (L-Phe) has rapidly increased in recent years to 14 kt in 2002, according to an authorative estimate [86], which is mainly due to the commercial success of the artificial sweetener aspartame. L-Phe has been produced by a number of chemoenzymatic routes in the past [87] (see Fig. 8.14) and many more have been developed [88] but never commercialized. Fermentation of L-Phe is now so efficient that it has rendered all of the chemoenzymatic procedures obsolete. 

Stock solution Weigh about 25 mg of Aspartame, transfer to a 50 mL volumetric flask, dissolve in and take to volume with water. (About 0.5 mg/mL). 

WS B Measure 5.0 mL of Aspartame STOCK solution into a 25 mL volumetric flask and take to volume with water (about 0.1 mg/mL). Use this solution for reproducibility of areas and migration times based on 5 consecutive injections. 

Caffeine/aspartame/benzoate standard mix. In a 25 mL volumetric flask, mix 4.0 mL of Aspartame STOCK solution, 5.0 mL of C-1, and 8.0 mL of B-I. Take to volume with water. Make one injection to show the resolution between the 3 peaks. 

Aspartame is a dipeptide ester, a-L-aspartyl-L-phenylalanine-OMe, 200 times as sweet as sucrose. Aspartame is utilized by now as a low-calorie sweetener in soft drinks, salad dressings, ready-made meals, table-top sweeteners, and pharmaceuticals, and had reached a market volume of 12000-15000 ha. One of the most successful and interesting syntheses is the Toyo Soda enzymatic process which runs on an industrial scale in a joint venture with DSM (Dutch State Mines, Geleen, NL). 

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