Stevioside

Stevioside

Phytochemistry 2003 Nov;64(5):913-21.
doi:10.1016/S0031-9422(03)00426-6

Geuns JM

Stevioside is a natural sweetener extracted from leaves of Stevia rebaudiana (Bertoni) Bertoni. The literature about Stevia, the occurrence of its sweeteners, their biosynthetic pathway and toxicological aspects are discussed. Injection experiments or perfusion experiments of organs are considered as not relevant for the use of Stevia or stevioside as food, and therefore these studies are not included in this review. The metabolism of stevioside is discussed in relation with the possible formation of steviol. Different mutagenicity studies as well as studies on carcinogenicity are discussed. Acute and subacute toxicity studies revealed a very low toxicity of Stevia and stevioside. Fertility and teratogenicity studies are discussed as well as the effects on the bio-availability of other nutrients in the diet. The conclusion is that Stevia and stevioside are safe when used as a sweetener. It is suited for both diabetics, and pku patients, as well as for obese persons intending to lose weight by avoiding sugar supplements in the diet. No allergic reactions to it seem to exist.

FDA claims stevia “unsafe”

U.S. health regulators warned Hain Celestial Group about a potentially unsafe herb in some of its herbal teas, saying it might be dangerous to blood sugar, reproductive, cardiovascular and renal systems.

The U.S. Food and Drug Administration sent a letter to Hain dated 17th August calling the herb, a natural sweetener made from a South American herb called stevia, “an unsafe food additive.” The agency released the letter on its web site on Tuesday.

The FDA letter said that although it has received requests to use stevia in food, “data and information necessary to support the safe use have been lacking.”

It also said “literature reports have raised safety concerns,” including those “about control of blood sugar, and the effects on the reproductive, cardiovascular and renal systems.”

It seems the FDA has never heard about countries like Paraguay or Japan.

Weird…

Stevia videos

This guy likes stevia:


This gal doesn't:

Stevia and VA-mycorrhiza

Selection of Arbuscular mycorrhizal fungi for stevia, Stevia rebaudiana (Bert.) Bertoni

Edilberto Princi Portugal, Giuliana C. Mercuri Quitério, Sylvio Luís Honório

pdf

Abstract:

Stevia rebaudiana (Bert.) Bertoni is a bush having its main economic and social value in its production of steviosides. The culture of stevia can be favored if young plant plugs are obtained in adequate conditions from protected environments, favorable substrates and by the use of arbuscular mycorrhizal fungi (AM). Mycorrhizas are symbiotic associations that establish themselves among the roots of the majority of vegetal species and soil fungi. As a result, mycorrhized plants are more competitive and tolerant of adverse environmental conditions than non-colonized plants.

The objective of the present experiment was to select efficient species of AM fungi for the development and production of steviosides from Stevia rebaudiana. To this end, an experiment was conducted in a vegetation house to test seven species of AM fungi (Glomus intraradices, Glomus macrocarpum, Glomus etunicatum, Entrophospora sp., Acaulospora sp.), two isolated from stevia, (CP 13 and CPVG) and a control treatment without inoculation. Vases (2L) with sterile soil were utilized and each treatment was repeated 5 times, entirely casualized. The harvest was made at the beginning of flowering, 63 days after seeding.

The aerial part was dried in an oven at 45°C and the dry weight and stevioside concentration were determined. The roots were tinted for colonization evaluation. The production of dry-leaf masses was significantly superior for the treatments with G. intraradices (1.65g), G. etunicatum (1.60g) and Acaulospora sp (1.62g), while Entrophospora sp (1.23g) remained on an intermediary scale and the least efficient were CP 13 (1.00g), CPVG (0.88g) and G. macromarpum (0.56g). Control produced only 0.41g. The accumulated quantity of steviosides was significant for G. intraradices, varying from 51% in relation to Acaulospora sp. (IAC13) to 350% in relation to control.
For the EM (ectomycorrhizal) total dry mass, leaves and accumulation of steviosides, no negative effect was observed for the studied fungi, G. intraradices standing out for all parameters. The colonization varied from 27% (G. macrocarpum) to 76% (Entrophospora sp and G. intraradices) and no colonization occurred for the non-inoculated treatment. The results demonstrate that the use of mycorrhizal fungi can significantly increase the production of biomass and the concentration of steviosides and that the fungi naturally established in the culture may not be more efficient for the culture’s development.

Stevia, safety, EU

In the previously mentioned article about stevia, a paragraph in the safety information section reads:

“More elaborate safety tests were performed by the Japanese during their evaluations of stevia as a possible sweetening agent. Few substances have ever yielded such consistently negative results in toxicity trials as has stevia. Almost every toxicity test imaginable has been performed on stevia extract or stevioside at one time or another The results are always negative. No abnormalities in weight change, food intake, cell or membrane characteristics, enzyme and substrate utilization, or chromosome characteristics. No cancer, no birth defects, no acute and no chronic untoward effects. Nothing.”

Now, if the Japanese have already assessed the safety of stevia, how come we in the eu now have to jump through hoops in order to have stevia approved as a “novel food”?

Life with Stevia

Former Fat Guy has an article about the nutrional and medical uses of stevia:

1. Life with Stevia※
2. Flavor enhancer※
3. Taste※
4. Bitter veins※
5. Medicinal uses※
6. Cardiovascular※
7. Safety※
8. References※

First stevia seedling

The rather poor photo on the left shows my first tiny stevia seedling, sown on 1st August, that emerged five days ago, and now sports its first — albeit very small — real leaves. Ungerminated seeds are visible here and there, shaming the seed bag's “Keimrate etwa 80%” (to be fair, the bag also reads “Ausreichend für mehr als 10 Pflanzen”).

/me sings ♪ Please grow for me ♫ … ☺

Growing Stevia

Today the Stevia seeds arrived from Germany, and for at start I have sown about one third of the seeds in a pot in my window sill. The instructions on the seed bag says that the seeds need light in order to germinate (see also this study from 1999), so I sprinkled the seeds on top of the moist soil, then covered the pot with see-through plastic to prevent the soil from drying out. See the illustrations from Medherbs.
You might also like to visit Iniman's stevia blog. He started a couple of months ago, and his plants look great.

Stevia in Japan

Stevia based sweeteners have a history of about four decades in Japan. However, its main uses were limited to pickles and seasonings because of the licorice like aftertaste of stevioside. Unsurprisingly, major effords have been undertaken to decrease the ratio of stevioside to rebaudioside a, which is neatly reflected in the product line of dic (tyo:4631):

The Hoten variety was registered in 1987 and gave rise to the now standard grade Chrysanta® product that contains 60% rebaudioside. The Seiten variety from 1990 is used in manufacturing of the high grade product containing 80% rebaudioside. And the Shuten variety from 2001 made possible the highest grade product containing more than 90% rebaudioside.

Sweet, innit? One should have in mind, though, that fairly recent research by Dyrskog et al. have shown that, in contrast to stevioside, rebaudioside does not improve glycemic control or blood pressure…

EU regulation 2000/196/EC

Just for the reference: Here's a link to the eu regulation 2000/196/ec, dated 22nd February 2000.

2000/196/EC:
Commission Decision of 22 February 2000 refusing the placing on the market of Stevia rebaudiana Bertoni: plants and dried leaves as a novel food or novel food ingredient under Regulation (EC) Nº 258/97 of the European Parliament and of the Council (notified under document number C(2000) 77) (Only the Dutch text is authentic)

See also

• uk safety evaluations

Stevia on Orkut

There are a few stevia related fora on Orkut:

•  Amigos da Stévia (Português)
•  Stevia rebaudiana (English)
•  Stevia rebaudiana Bertoni (Español)
•  Stevia Society of India (English)

See also the announcement of a mailing list for friends of stevia on google groups.

Mailing list

For those who wish to exchange ideas and experiences about stevia with similarly inclined there is now an english spoken mailing list on google groups.

See also the list of stevia related communities on Orkut.

Enjoy!

Steviol glycosides in food

Risk in brief

1. The Joint Food and Agriculture Organization / World Health Organization Expert Committee on Food Additives (JECFA) had evaluated the safety of stevioside in 1998. Owing to shortcomings and incompleteness of the research findings, JECFA did not make any conclusion regarding its safety at that time.
2. JECFA in 2004 re-evaluated the safety of stevioside and other steviol glycosides and concluded that steviol glycosides did not demonstrate any genotoxic and carcinogenic potential from available evidence.
3. JECFA in 2004 allocated a temporary acceptable daily intake (ADI) of 2 mg/kg bw for steviol glycosides, expressed as steviol. Dietary intake of steviol glycosides at level below this safety reference value is unlikely to cause adverse effects in humans in general.
4. However, JECFA noted the potential pharmacological effects of stevioside in patients with hypertension or with type-2 diabetes (or noninsulin-dependent diabetes) and raised concern whether these pharmacological effects could lead to adverse effects in some individuals (e.g. those with hypotension or diabetes). JECFA therefore considered that more scientific data is required for further evaluation in 2007.
5. In June 2007, JECFA considered some newly available data and opined that they did not raise additional concerns regarding the safety of steviol glycosides, but the results of ongoing clinical studies would be essential for further evaluation of the substances. The temporary ADI was therefore extended until 2008, pending submission of the results of the ongoing studies.

Source: Centre for Food Safety, Risk in Brief Nº 10 (July 2007): Stevioside in Food

Cultivation of Stevia in EU

The FAIR-3751 project intended to carry out a significant improvement of the cultivation technique by closely associating agronomists, process technologists and construction engineers. The executed work showed that a cultivation of Stevia rebaudiana in the eu is feasible. The following aims have been achieved:

• development of an optimised cultivation technique which is economically adapted to european farms, notably through mechanisation
• development of an adapted Stevia harvester
• development of a green crop dressing line to facilitate near farm extraction

In autumn 2007 the improved website of University of Hohenheim will be launched.

The chances of being able to cultivate Stevia in southern european regions (Greece, Italy, Spain, Portugal) are particularly good. Stevia is suitable to substitute the cultivation of tobacco for which financial support granted by the eu will end in 2010. “Stevia is able to increase the net operating income of tobacco farmers by up to 400 percent — without subsidies,” says Prof. Dr. Thomas Jungbluth (2004).

SteviaRebaudiana.com

SteviaRebaudiana.com is an information source on stevia, its history, legal situation and more. Well worth a visit.

UK safety evaluations

The UK Food Standards Agency writes about stevia and stevioside:

Stevioside is a high intensity sweetener, 250-300 times sweeter than sucrose.

It is isolated and purified from the leaves of the Stevia plant (Stevia rebaudiana Bertoni), where it is present at levels up to 13%, and has been used for a number of years as a sweetener in South America, Asia, Japan and China.

As a result of the outcome of safety assessments which have been carried out Stevia and stevioside are not permitted for sale as food or food ingredients in the UK or elsewhere within the EU.

See also

• the letter setting out the acnfp’s views (1998)
• scf's opinion on Stevia (1999)
• eu regulation 2000/196/ec (2000)

Siraitia grosvenorii

Wikipedia knows the lo han guo fruit mentioned earlier by its botanical name Siraitia grosvenorii (syn. Momordica grosvenorii and Thladiantha grosvenorii), and the chinese entry even sports a photo of the fruit.

Lo Han Guo

Mark Isaac Thyss over at “Garden of Healing” talks about Lo Han Guo:

Luo han guo is a very sweet fruit found in Southern China. It is low-calorie and extracts of it are now being marketed as a sweetener.

The fruit extract is nearly 300 times sweeter than sugar and has been used as a natural sweetener in China for nearly a millennium due to its flavor and lack of food energy. It has also been used in traditional Chinese medicine.

Lo han guo is a vine cultivated in special gardens cleared in the mountain forests. The plant is rarely found in the wild and has been cultivated for hundreds of years.

The “300 times sweeter than sugar” sounds a bit like stevia, doesn't it? I wonder where I can find this fruit…

Update: See also the entry about Siraitia grosvenorii.

Stevioside counteracts α-cell hypersecretion

Stevioside counteracts the α-cell hypersecretion caused by long-term palmitate exposure

Am J Physiol Endocrinol Metab. 2006 Mar;290(3):E416-22.
DOI 10.1152/ajpendo.00331.2005 (pdf)

Hong J, Chen L, Jeppesen PB, Nordentoft I, Hermansen K

Long-term exposure to fatty acids impairs β-cell function in type 2 diabetes, but little is known about the chronic effects of fatty acids on α-cells. We therefore studied the prolonged impact of palmitate on α-cell function and on the expression of genes related to fuel metabolism. We also investigated whether the antihyperglycemic agent stevioside was able to counteract these effects of palmitate. Clonal α-TC1-6 cells were cultured with palmitate in the presence or absence of stevioside. After 72 h, we evaluated glucagon secretion, glucagon content, triglyceride (TG) content, and changes in gene expression. Glucagon secretion was dose-dependently increased after 72-h culture, with palmitate at concentrations ≥0.25 mM (P < 0.05). Palmitate (0.5 mM) enhanced TG content of α-cells by 73% (P < 0.01). Interestingly, stevioside (10^–8 and 10^–6 M) reduced palmitate-stimulated glucagon release by 22 and 45%, respectively (P < 0.01). There was no significant change in glucagon content after 72-h culture with palmitate and/or stevioside. Palmitate increased carnitine palmitoyltransferase I (CPT I) mRNA level, whereas stevioside enhanced CPT I, peroxisome proliferator-activated receptor-γ, and stearoyl-CoA desaturase gene expressions in the presence of palmitate (P < 0.05). In conclusion, long-term exposure to elevated fatty acids leads to a hypersecretion of glucagon and an accumulation of TG content in clonal α-TC1-6 cells. Stevioside was able to counteract the α-cell hypersecretion caused by palmitate and enhanced the expression of genes involved in fatty acid metabolism. This indicates that stevioside may be a promising antidiabetic agent in treatment of type 2 diabetes.

(First published October 4, 2005)

Glycosides from Stevia rebaudiana

Glycosides from Stevia rebaudiana

Chem Nat Comp, 2007, 43(1):81-85 (Jan 2007)
DOI 10.1007/s10600-007-0037-x (pdf)

G. I. Kovylyaeva, G. A. Bakaleinik, I. Yu. Strobykina, V. I. Gubskaya, R. R. Sharipova, V. A. Al’fonsov, V. E. Kataev and A. G. Tolstikov

A new laboratory method for isolating the glycosides stevioside and rebaudiosides A and C from leaves of Stevia rebaudiana was proposed. According to HPLC, the glycoside contents in plants grown in Russia (Voronezh Oblast’) and Ukraine (Crimea) were 5–6% (stevioside) and 0.3–1.3% (rebaudiosides A and C).

(Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 68–71, January–February, 2007)

Green gold for Paraguay

I just stumbled upon a stevia related news article on France 24's international news channel:

Paraguay is hoping a small herb that is not trafficked, addictive, or even fattening, could prove to be the real deal that the food industry has been waiting for. […]
“Coca-Cola's announcement has sparked a giant interest,” said Nelson Gonzalez, head of the stevia chamber of commerce, a trade group of producers under the aegis of Paraguay's ministry of industry.

Read it all^※.

Wikipedia

Wikipedia has a few relevant articles:

• Stevia
• Stevioside
• Rebaudioside

Stevia sweet leaf

I accidentally stumpled upon fellow blogger italman's stevia blog Stevia Sweet Leaf. He seems to grow his own stevia from seeds he obtained from the Internet. Sweet (no pun intended)!

Sunwin International Neutraceuticals

Sunwin International Neutraceuticals, Inc. (otc:suwn) manufactures and sells stevioside, a natural sweetener, veterinary products and herbs used in traditional Chinese medicine in the People's Republic of China. All of Sunwin's operations are located in the People's Republic of China. Sunwin's operations are organized into three main product groups: stevioside, a natural sweetener; veterinary medicines, and traditional Chinese medicine formula extracts. It also engages in new product development both through its internal research facilities and in partnership with a number of research facilities in the People's Republic of China, including Shandong Medical University, Kelong Bio-Tech Co., Ltd. and Tianfulai Bio-Tech Technology Co. Ltd. (Beijing).

Stevia info

Stevia info claims to be a non-profit project dedicated to providing accurate and credible information about stevia, the all-natural, zero-calorie sweetener.

Cargill, Coca-Cola team up on new sweetener

Cargill and The Coca-Cola Company established a global development partnership to transform stevia into a natural way to sweeten foods and beverages with zero calories. The result of this partnership is rebiana (cache).

European Stevia Association

The European Stevia Association, eustas, is a non-profit organisation whose main aims are the promotion and coordination of all activities focussing on research and health in relation to Stevia rebaudiana and related compounds, to show that they are safe for the human consumption and to place a new application for Stevia rebaudiana as a sweetener against the Scientific Committee on Food of the European Commission.

Rebaudioside A does not improve glycemic control or blood pressure

The Diterpene Glycoside, Rebaudioside A, Does not Improve Glycemic Control or Affect Blood Pressure After Eight Weeks Treatment in the Goto-Kakizaki Rat

Rev Diabetic Stud, 2005, 2(2):84-91
DOI 10.1900/RDS.2005.2.84

Dyrskog SE, Jeppesen PB, Chen J, Christensen LP, Hermansen K.

The plant, Stevia rebaudiana Bertoni (SrB), has been used for the treatment of diabetes in traditional medicine. Previously, we have demonstrated that long-term administration of the glycoside stevioside has insulinotropic, glucagonostatic, anti-hyperglycemic and blood pressure-lowering effects in type 2 diabetic animal models. The aim of this study was to elucidate if long-term administration of rebaudioside A, another glycoside isolated from the plant SrB, could improve glycemic control and lower blood pressure in an animal model of type 2 diabetes. We divided male Goto-Kakizaki (GK) rats into two groups which were fed a standard laboratory chow diet for eight weeks. The diet was supplemented with oral rebaudioside A (0.025 g/kg BW/day) in the experimental group. Blood glucose, weight, blood pressure and food intake were measured weekly. Animals were equipped with an intra-arterial catheter, and at week eight the conscious rats underwent an intra-arterial glucose tolerance test (IAGTT) (2.0 g/kg BW). During the IAGTT, the level of glucose, glucagon, and insulin responses did not differ significantly between the two groups. Fasting levels of glucose, glucagon, insulin or levels of blood lipids did not differ between the groups throughout the study period. We observed no effect on blood pressure or weight development. In conclusion, oral supplementation with rebaudioside A (0.025 g/kg BW/day) for eight weeks did not influence blood pressure or glycemic control in GK rats. Rebaudioside A failed to show the beneficial effects in diabetic animals previously demonstrated for stevioside.

Welcome

This blog will focus on one of nature's sweet wonders, stevia (“sweet­leaf”), a shrub native to the northern regions of South America. Its leaves contain several chemicals called glycosides, which have a sweet taste. The major glycoside, stevioside, is a common sweetener in use in Japan and Korea.

Enjoy your stay here.