Sweeteners stevioside

The binding specificity of d-[ C]glucose by the taste-papillae membranes, compared to that of control membranes isolated from epithelial tissue, has been confirmed in two studies. One inherent problem in the approach is that the stimuli, primarily carbohydrate sweeteners, are not ideal model compounds to use, as they are not active at low concentrations and do not show sufficiently high binding-constants. The use of other stimulus compounds that are at least several hundred times sweeter than sucrose, such as saccharin, dihydrochalcone sweeteners, dipeptide sweeteners, stevioside, perillartine and other sweet oximes, the 2-substituted 5-nitroanilines, and... 

There have never appeared reports proving that the use of Stevia or stevioside enhances the number of cancers in populations, even after a very long time of use (eg. Paraguay more than 500 years, Japan more than 25 years, South-Korea 15 years, Brasil 12 years, China 11 years or the USA since 1995 admitted as a dietary supplement). Thus the general conclusion is that Stevia and its sweeteners stevioside and rebaudioside A are completely safe. 

Stevioside is an ent-kaurene type diteipenoid glycoside isolated from leaves of Stevia rebaudiana Bertoni. Leaves of this plant produce zero-calorie diterpene glycosides (stevioside and rebaudioside), a nmi-nutiitive, high-potency sweetener. Stevioside content in leaves will vary in field grown plants and is also influenced by agroclimatic conditions. Stevia leaves are also in use for their medicinal benefits. In this chapter, natural distribution and cultivation of Stevia,... 

RPLC with MS detection was used for the analysis of seven artificial sweeteners (aspartame, saccharin, acesulfame-K, neotame, sucralose, cyclamate, and alitame) and one natural sweetener (stevioside). Samples were extracted using methanokwater and injected without any cleanup into the LC—MS system. Separation is carried out using a Cis column and gradient elution. Sweeteners were quantified using selective-ionization recording (SIR) at m/z 178, 397, 377, 293, 641, 312, 162, and 182 for cyclamate, sucralose, neotame, aspartame, stevioside, alitame, acesulfame-K, and saccharin, respectively, with a warfarin sodium m/z = 307) used as an internal standard [24]. For a detailed discussion of other analytical methods to determine artificial sweeteners, refer to [25]. 

FIGURE 14 NMR spectrum of the natural sweetener stevioside (CsgHeoOis ). 

Stevioside and rebaudioside A are diterpene glycosides. The sweetness is tainted with a bitter and undesirable aftertaste. The time—intensity profile is characteristic of naturally occurring sweeteners slow onset but lingering. The aglycone moiety, steviol [471 -80-7] (10), which is the principal metaboHte, has been reported to be mutagenic (79). Wide use of stevia ia Japan for over 20 years did not produce any known deleterious side effects. However, because no food additive petition has been presented to the FDA, stevioside and related materials caimot be used ia the United States. An import alert against stevia was issued by the FDA ia 1991. In 1995, however, the FDA revised this import alert to allow the importation and use of stevia as a diet supplement (80), but not as a sweetener or an ingredient for foods. Several comprehensive reviews of stevia are available (81,82). 

Sweeteners can be roughly divided into two groups bulk and intense sweeteners. Prodolliet (1996) and Gloria (2000) reviewed thoroughly the analysis and properties of intense sweeteners acesulfame-K, alitame, cyclamate, aspartame, glycyrrhizin, neohesperidin DC, saccharin, stevioside, sucralose and thaumatin. They are generally used in low calorie products such as diet... 

SCIENTIFIC committee ON FOOD, Opinion on Stevioside as a sweetener, SCF/CS/ADD/EDUL/167, Bmssels, European Commission, 1999. 

Most sweet compounds including the commercial sweeteners, are small molecular weight compounds but there are also sweet macromolecules both synthetic and natural. It was thought that compounds with molecular masses over 2 500 would generally be tasteless. It was assumed that macromolecules such as proteins could elicit a sweet taste similar to small molecules such as sucrose and stevioside until the discovery of miraculin. 

The leaves of Stevia rebaudiana (Compositae) are a source of several sweet glycosides of steviol (26) (Fig. 15) [1, 61]. The major glycoside, stevioside (27), is used in oriental countries as a food sweetener and the second major glycoside named rebaudioside (28), which is sweeter and more delicious than stevioside, is utilized in beverages. 

Stevia Stevia rebaudiana) Uses Natural sweetener, hypoglycemic and hypotensive properties Actions Multiple chemical components sweetness d/t glycoside, stevioside hypotensive effect may be d/t diuretic action or vasodilation action Available forms Liq extract, powder, caps Notes/SE HA, dizziness, bloating Interactions T Hypotensive effects W/ antihypertensives esp CCB, diuretics EMS Monitor BP does not encourage dental caries may -1-glucose St. John s Wort (Hypericum perforatum) Uses Mild-mod depression, anxiety, anti-inflammatory, immune stimulant/anti-HIV/antiviral, gastritis, insomnia, vitiligo Action MAOI in vitro, not in vivo bacteriostatic bactericidal, T capillary blood flow, uterotonic activity in animals Efficacy Variable benefit w/ mild-mod depression in several trials, but not always seen in clinical practice Available forms Teas, tabs, caps, tine, oil ext for topical use Dose 2-4 g of herb or 0.2-1 mg of total hypericin (standardized extract) daily Notes/SE Photosensitivity (use sunscreen) rash, dizziness, dry mouth, GI distress Interactions Enhance MAOI activity, EtOH, narcotics, sympathomimetics EMS T Risk of photosensitivity Rxns t effects of opioids and sympathomimetics... 

Stevioside. Derived from the roots of the herb Stevio rebaudiana. this compound has found limited use in Japan and a few other countries as a low-calorie sweetener having about 300 times the sweetening power of sucrose. The compound has not been investigated thoroughly by a number of countries with strong regulatory agencies and, therefore, is not on the immediate horizon for wide consideration as a sweetener. 

The dried leaves of S. rebaudiana have been used in Paraguay for many years to sweeten bitter drinks. From 3 to 8% of the dned leaves is stevioside, which is a diterpene glycoside as shown by the formula below. 

Stevia sweeteners are extracted from the leaves of Stevia rebaudiana Bertoni (Compositae), an herb native to Paraguay but cultivated in Southeast Asia, Japan, Paraguay, Brazil, Israel, and the United States. The sweet constituents of stevia include eight diterpene glycosides stevioside, ste-violbioside, rebaudiosides A, B, C, D, E, and dulcoside A, which collectively are 100-300 times... 

Extraction of stevia sweeteners from dried leaves can be accomplished with acetonitrile in the presence of calcium carbonate solution (116) or with boiling water adjusted to pH 9.0 (107). Ahmed and Dobberstein (117) extracted stevioside and rebaudioside A and C from dried leaves of S. rebaudiana in a micro-Soxhlet apparatus. They observed that chloroform/methanol provided the best results, compared to chloroform or to chloroform/methanol/water. Extraction of stevioside, rebaudioside A and C, and dulcoside A can also be performed by subcritical fluid extraction using C02 and methanol as a modifier. Such an extraction technique has been gaining popularity as an analytical tool because it is rapid, simple, and less expensive in terms of solvent cost (110). Beverages, tabletop sweeteners, beverages containing pulp, and candies are prepared as indicated in Sec. I.C (110,115,118). 

High-performance LC is routinely used for the analysis of stevia sweeteners in plant material or in food and beverages. The first successful HPLC separation of stevioside and rebaudioside A... 

C Toskulkao, L Chaturat, P Temcharoen, T Glinsukon. Acute toxicity of stevioside, a natural sweetener, and its metabolite, steviol, in several animal species. Drug Chem Toxicol 20( 1—2) 31—44, 1997. 

Formulators in most markets now have a wide range of sweeteners available to use either alone or in combination. As Figures 4.1 and 4.2 show, the main intense sweeteners in use in soft drinks today are acesulfame K, aspartame, saccharin and cyclamate. Currently of less importance commercially (either because they are new to the market or because they have not found significant use in soft drinks), but still approved for use in soft drinks in some markets, are thaumatin, neohesperidin diliy-diochalcones, alitame, stevioside, sucralose and neotame. 

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