Stevia leaves

Table 1. Diterpene Glycosides Isolated from Stevia Leaves...

The regulatory position of stevioside varies in different regions of the world. Japan is the main market for stevioside and consumes 90% of the world s supply of stevia leaves (Richard, 2002). Stevioside is used in Japan in a variety of applications, including soft drinks. In other markets, the use of stevioside, if permitted at all, is limited to supplements. In the United States, the FDA issued an import alert in May 1991 blocking the import of and sale of stevia products, following the results of a preliminary mutagenicity study. In 1995, the FDA revised the import alert to allow the sale of stevia and its extracts as a food supplement, but not as a sweetener. It currently does not have GRAS status and is considered to be an unsafe food additive (Richard, 2002). 

A literature search could not reveal any publications about a possible allergenic activity of Stevia plants, dried leaves or stevioside itself Kinghom came to the same conclusions no published reports have appeared that would suggest that extracts of Stevia leaves are immunologically active when taken internally [36]. Similarly there is no evidence that any of the constituents of Stevia caused allergic contact dermatitis. 

More information on the use of Stevia in different covmtries can be found in the List of Food Additives excluding chemical s)mthetics (Japanese Ministery of Health and Welfare). The consumption of Stevia leaves in 1989 is given for different countries Japan (2000 tons/year), Brazil (600 tons/year), China (400 tons/year). South Korea (300-400 tons/year), Thailand (100 tons/year), Taiwan (Formosa) (small quantities), Paraguay (150 tons/year) and Argentina (60 tons/year). Even in Belgium, England and The Netherlands several tons of dried leaves have been consumed. In 1989 the (known) world production was estimated at 4100 tons/year. No problems have been published in scientific literature... 

The purity of the stevioside is not always the same in the various experiments or unknown in some experiments. However, in most experiments the purity of the stevioside used is over 90 % and often over 95%. The impurities occurring in the different stevioside preparations are due to compounds extracted from the Stevia leaves that themselves have been shown to be completely safe. Therefore, the problem of the purity of the stevioside is more a point for academic debate than a matter of concern of human health. Stevioside is safe as well as Stevia leaves and their crude extracts. Therefore, the occurrence of a slightly varying percentage (5-10%) of residual leaf extract in the stevioside preparation will not be... 

Although it was reported [24] that a water decoction of Stevia leaves was used as an oral contraceptive by Paraguayan Matto Grosso Indian tribes and that these decoctions reduced the fertility in adult female rats of proven fertility, subsequent studies could not reproduce their results. Moreover, [25] reported that the use of Stevia as a contraceptive has never been confirmed [19, 26] and in a field study made throughout Paraguay not any local use of Stevia as a contraceptive could be found. Inquiries were made in Asuncion, Concepcion, Pedro Juan Caballero, and in Cerro Kuatia. In the last mentioned location, interviews were conducted with members of the native Indian group, Pay Tavy Tera, as well as other populations that have recently settled in the area. 

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,... 

Zhang, S. Q., Kumar, A., and Kutowy, O. (2000). Membrane based separation scheme for processing sweeteners firam stevia leaves. Food Res. Int. 33, 617-620. 

Stevioside 30,000 Extract of stevia leaves, known as sweet leaf or sugar leaf. Marketed as Truvia , Pure Via , or Enliten . All the sugar units are glucose. 

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