Saccharin proteins

Finally, some amphiphilic sweeteners, eg, aspartame, saccharin, and neohesperidin dihydrochalcone, have been shown to be capable of stimulating a purified G-protein direcdy in an in vitro assay (136). This suggests some sweeteners may be able to cross the plasma membrane and stimulate the G-protein without first binding to a receptor. This type of action could explain the relatively longer response times and the lingering of taste associated with many high potency sweeteners. 

Mechanistic studies carried out in the course of recent years indicated that sodium saccharin may be involved in the formation of specific proteins occurring in rat urine which may contribute to the formation of bladder tumours. Most scientists and regulatory authorities now share the view that the incidence of bladder tumours in male rats after saccharin ingestion is species-specific and therefore probably without any significance for humans. Accordingly, the former temporaiy ADI of 0-2.5 mg/kg of body weight has been raised to 0-5 mg/kg by JECFA21 and the SCF.22... 

Every patient with diabetes requires some form of dietary assessment, and often therapy. This is important to allocate the relative amounts of energy derived from carbohydrate, protein and fat of total recommended daily calories in proportion to the patient s body weight and height and daily requirements, while avoiding atherogenic diets. Diets with high carbohydrate content (50-60%), low fat (30-35%) and adequate protein (10-15%) is recommended. Fibre-rich foods are preferable. The use of non-nutritive sweeteners (saccharin, aspartame, ace-sulfame K and sucralose) are acceptable. Alcohol intake should be assessed since excess consumption... 

Sweet Taste. The mechanism of sweetness perception has been extensively studied because of its commercial importance. Many substances that vary in chemical structure have been discovered which are similar to the taste of sucrose. Commercial sweeteners include sucralose, acesulfame-K, saccharin, aspartame, cyclamate (Canada) and the protein thaumatin 4), Each sweetener is unique in its perceived sensation because of the time to the onset of sweetness and to maximum sweetness, ability to mask other sensations, persistence, aftertaste and intensity relative to sucrose [TABLE IT. For example, the saccharides, sorbitol and... 

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. 

Saccharin Proliferative changes in male rat bladder epithelium Considered to be species-specific with large doses used. Mechanism of action may involve urinary proteins not normally found in humans [23,40,47-49]... 

Do these diverse compounds give rise to a common perception of sweetness or to qualitatively different sensations Sweetness does indeed appear to be a unitary percept (Breslin et al. 1994,1996). However, some sweeteners may be discriminable on the basis of their activation of other sensory transduction mechanisms or differences in the temporal properties of their sensory action. For example, the sweetener sodium saccharin activates bitter receptors in some people (Kuhn et al. 2004 Pronin et al. 2007), and also inhibits sweet taste at high concentrations (Galindo-Cuspinera et al. 2006). Sweet proteins such as thaumatin and monellin can have a slow onset or evoke a prolonged sweetness compared with sugars (Faus 2000), likely owing to a relatively high affinity for the sweet taste receptor. 

Faus I (2000) Recent developments in the characterization and biotechnological production of sweet-tasting proteins. Appl Microbiol Biotechnol 53 145-151 Fisher GL, Pfaffmann C, Brown E. (1965) Dulcin and saccharin taste in squirrel monkeys, rats, and men. Science 150 506... 

Finally, it is to mention that DES are good solvents also for strong hydrogen-bonding compounds, such as unprotected sugars and cellulose, whereas simple choline salts having as counteranion acetate, citrate, dihydro-genphosphate (Scheme 3) and saccharinate have been proposed as unique solvents for important biomolecules, such as proteins.It has been shown that some proteins are soluble, stable and remain active in these ILs. 

Fuller, J. (1974). Single-locus control of saccharin preference in mice. ]. Hered. 65,33-36. Gibbs, B.F., Alii, 1., and Mulligan, C. (1996). Sweet and taste-modifying proteins A review. 

Aspartame (NutraSweet), which has replaced saccharin as the principal artificial sweetener, is used in more than 3000 products and accounts for 75% of the one-hiUion-dollar worldwide artificial sweetener market. It is a dipeptide derivative made from aspartic acid and the methyl ester of phenylalanine. Aspartame can he digested, and its caloric value is approximately equal to that of proteins. However, since much smaller amounts of aspartame than of table sugar are needed for sweetness, many fewer calories are consumed in the sweetened food. Aspartame is not stable at cooking temperatures, which limits its use as a sugar substitute to cold foods and soft drinks. 

Artificial sweeteners taste sweet because they fit into the receptor pocket that normally binds sucrose. In fact, both aspartame and saccharin bind to the active site in the Tlr3 protein more strongly than sugar does For this reason, artificial sweeteners are "sweeter than sugar." It takes 200 times as much sucrose as aspartame to trigger the same amount of nerve signal transmission from taste cells. 

HPLC has also found substantial application in the analysis of the high potency sweeteners. In one methodology, equilibrium dialysis of a food against water (15 h, 12,000-14,000 dalton cutofO was used to eliminate interference from lipids, carbohydrates, and proteins. Direct chromatography of the dialysate on a reverse phase column (UV detection 220 r m) gave very good results for acesulfame-k, saccharin, and aspartame. 

The final resolution to the question of the exact nature of acid produced by the stomach was provided in 1823 by William Prout, a brilliant physidan with diverse interests outside of medidne. Prout was productive in the fields of chemistry, meteorology, physiology, and clinical medicine. In addition, he was one of the first scientists to apply chemical analysis to biologic materials. He was, thus, able to demonstrate circadian rhythms in his own expired carbon dioxide as well as to propose that the destruction of tissues produced excretory materials, such as uric acid, urea, and carbonic acid. In 1827, he developed a classification of foods into subgroups saccharinous (carbohydrates), oleaginous (fats), and albuminous (proteins). 

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