Rebaudiosides

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). 

The plant Stevia rebaudiana bertoni has been studied in depth because it was discovered that this plant is the source of six sweet-tasting diterpene glycosides. They are stevioside, rebaudiosides A, C, D, E and dulcoside A. (Table 1). These sweet diterpene glycosides, as well as a complex mixture of organic compounds of which more than a hundred compounds have been identified, are found mainly in the leaves of the plant. The leaves contain a complex mixture of labdane diterpenes, triterpenes, stigmasterol, tannins and volatile oils. There is an abundance of reviews and patents relating to these sweet diterpene glycosides. 

Rebaudioside D glc2—Iglc glc2—Iglc glc 250M50... 

There are many patents and journal articles that describe processes to produce the principal sweet diterpene glycosides stevioside and in particular, rebaudioside A. Many of the reported methods of production require the use of ion exchange columns or gases and are not satisfactory if the scale-up to commercial quantities are required. Most methods for extraction and purification of the sweet diterpene glycosides from Stevia use complicated processing of the crude extracts. Generally, the recovery processes of the principal two diterpene glycosides stevioside and rebaudioside A involve ... 

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 rebaudiana (Bertoni) Hemsl. Tian Jiu (Stevia) (stem, leaf) Stevioside, steviolbioside, rebaudiosides, austroinulin.57 Treat diabetes, tonic, lower blood pressure. 

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... 

Detection of stevia glycosides after separation by HPLC has been performed by high-sensitivity refractive index (106,116) and by UV at 210 nm (110,115-118). The use of UV at 210 nm allowed detection of 0.4 fig for stevioside, steviolbioside, rebaudioside B, and dulcoside A and 0.8 fig for rebaudiosides A and C-E. This sensitivity is higher than that obtained with the RI detector-2 /ig of stevioside and rebaudioside A (116). 

SS Chang, JM Cook. Stability studies of stevioside and rebaudioside A in carbonated beverages. J Agric Food Chem 31(2) 409-412, 1983. 

Y Kitada, M Sasaki, Y Yamozoe, H Nakazawa. Simultaneous determination of stevioside, rebaudioside A and C and dulcoside A in foods by high-performance liquid chromatography. J Chromatogr 474(2) 447-451, 1989. 

MS Ahmed, RH Dobberstein. Stevia rebaudiana. II. High-performance liquid chromatographic separation and quantitation of stevioside, rebaudioside A and rebaudioside C. J Chromatogr 236(2) 523-526, 1982. 

K Fujinuma, K Saito, M Nakazato, Y Kikuchi, A Ibe, T Nishima. Thin layer chromatographic detection and liquid chromatographic determination of stevioside and rebaudioside A in beverages and... 

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