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A strategy that could partially or totally reduce the use of chemical synthesis fertilizers is the application of cyanobacteria with agricultural potential that promote plant growth, which powers them in the conception of a sustainable agriculture. The study evaluated the effect of four concentrations of an extract of Limnospira maxima (0, 4, 8, and 12 mg mL-1), on some physiological aspects of Stevia rebaudiana and Solanum melongena in house vegetation. Treatments were arranged under a complete random design and parameters of gas exchange, chlorophyll a fluorescence, biometric characteristics and biomass distribution were measured. The most important results indicated that in Stevia rebaudiana and Solanum melongena the rates of net photosynthesis increased respectively by 40,03% and 22,45% when cyanobacteria was applied. On the other hand, plants of both species that were inoculated required less electrons to maximize their photosynthesis rates, increased leaf area, plant height and biomass distribution in roots and leaves. The most important physiological indicator was net photosynthesis and this was positively correlated with almost all the parameters studied. The results suggest that the use extracts of L. maxima may be a biotechnological alternative of organic fertilization useful for the development of sustainable agriculture. [ABSTRACT FROM AUTHOR]

Food provides nutrients, but must be palatable to consumers. Stevia is a plant with sweetening and biofunctional properties. The objective of this research was to develop brown rice crackers supplemented with Moringa oleifera and Stevia rebaudiana and to evaluate the physicochemical, sensory and moisture quality during storage. Aqueous extract of Stevia (5, 10 and 20% W/W) and Moringa shoots (20% W/W) were prepared, which were mixed with brown rice for the production of different groups of cookies. One group without Stevia and another without Stevia and Moringa (basic cookie) were made. The determination of the physicochemical characteristics was carried out by the near infrared spectroscopy method, the humidity by the gravimetric method in humidity balance. The shelf life was determined for 105 days of storage and the degree of acceptance by consumers, through sensory analysis. The experimental design was unifactorial with a completely random distribution. All groups of cookies obtained humidity values below the established maximum limit (12 %). The protein content, fat, fiber and ash in the cookies supplemented with the aqueous extracts of Moringa and Stevia were higher compared to the basic cookies. In the sensory analysis, all the cookies obtained a high degree of acceptability, and the cookies supplemented with Stevia 10 % (W/W) showed the greatest preference. The optimal concentration in brown rice crackers was identified as those supplemented with Moringa 20 % (W/W) and Stevia 10% (W/W), with good acceptability and high nutritional value. [ABSTRACT FROM AUTHOR]

The article presents a study on the effect of planting distance on biomass production and steviol glycoside content of the Stevia rebaudiana Bertoni var. Morita II plant under field conditions in Cuba. It was determined that the greater planting distance (25x20 cm) obtained the best results in terms of yield and steviol glycoside content. This study provides relevant information for the cultivation of Stevia rebaudiana in Cuba. Additionally, the article mentions other studies related to the cultivation of the plant and its influence on growth and secondary metabolites. [Extracted from the article]

Stevia (Stevia rebaudiana Bertoni) is a plant with sweetening properties that offers numerous health benefits. This work analyzed the publications with the greatest impact related to the study of stevia and the most important results of the Scopus database revised in October 2021. The documents were classified in terms of number of publications per year, scientific journals, authors, affiliation, countries, type of document and by subject area. The bibliometric study revealed 2,748 publications in 67 years with a higher prevalence in the area of agricultural and biological sciences. Solvent extraction is the most widely used method and the variables that most affect the extraction process are solute size, solute:solvent ratio, extraction temperature, pH and operation time. [ABSTRACT FROM AUTHOR]

Contextualization: The areas planted with stevia have been growing significantly in response to the new trends in consumption of low-calorie and natural foods. The effects of high radiation levels, due to global climate change, have evidenced the need to development new studies about the physiological behavior of the photosynthetic pigments of agricultural species. Knowledge gap: The lack of knowledge of the behavior of stevia crops in the context of current and future environmental changes (mainly, the increases in solar radiation levels) means that farmers and producers do not obtain the expected yields. Purpose: The objective of this study was analyze the effect of different levels of solar radiation and nitrogen fertilization, under greenhouse conditions, on the production of photosynthetic pigment in Stevia rebaudiana Bert. Methodology: The trial was done using as completely randomized design (CRD), employing a 2 x 6 factorial arrangement and 16 replicates per treatment; factor A corresponded to two levels of incident solar radiation (300 and 1.500 pmol photons, m-2 s-1 corresponding to 20% and 100% radiation respectively) and factor B corresponded to six doses of nitrogen (0, 60, 120, 180, 240 and 300 kg ha-1). Chlorophyll a, b, and total chlorophyll content was evaluated in young and healthy leaves eight months after transplanting. Results and conclusions: The results showed that the contents of chlorophyll a, b and total were significantly affected by solar radiation, but not by the nitrogen supplied. In both radiation environments, the contents of chlorophyll a were higher than the contents of chlorophyll b in all plants evaluated. In the environment of lower solar radiation (300 pmol of photons m-2 s-1), the maximum levels of the photosynthetic pigments were presented. In the environment of 1.500 pmol of photons. m-2 s-1, the contents of chlorophyll a, b and total were lower in control plants (0 kg ha-1). [ABSTRACT FROM AUTHOR]

Stevia leaves (Stevia rebaudiana) are a source of bioactive compounds beneficial to human health; among them, steviol glycosides standout. The commercial value of dehydrated stevia leaves is related to their physical appearance and the concentration of glycosides. The hypothesis of the study was that the quality of stevia leaves, based on the content of bioactive compounds present in the leaves, can be visible and modified by drying. To test it, the objective was to evaluate the effect of temperature, air velocity, and load density of stevia leaves in a fluidized bed dryer unpacked and packed on the characteristics of colour, steviol glycoside concentration (stevioside and rebaudioside A), total phenolic compound concentration, flavonoid concentration, and antioxidant capacity. The physicochemical variables were evaluated by CIEL*a*b* coordinates, reverse phase liquid chromatography, Folin-Cicolteau colourimetric methods, aluminum chloride, and DPPH* free radical inhibition assay. The effect of process variables was evaluated with a full factorial arrangement with 24 combinations of factors and three sampling replicates. The fluidized bed configuration affected (p£0.05) the concentration of steviol glycosides in the dry leaf material. In both configurations the steviol glycoside content increased between 230-290% compared to fresh leaf material. For the unpacked bed configuration, the bitter aftertaste (rebaudioside/stevioside ratio) was higher than the original evaluated in the fresh material. All process variables had a significant influence on polyphenol concentration. The packed bed configuration increased the concentration of phenolic compounds (p£0.05) up to 248%. Whereas, with unpacked bed it decreased up to 17% (p£0.05) in relation to fresh material. The decrease in drying times and the increase of bioactive compounds (steviol glycosides and antioxidant compounds) in stevia leaf make of this drying method a useful tool for the management and preservation of plant materials containing secondary metabolites of economic importance. [ABSTRACT FROM AUTHOR]

Objetive To compare the effect of Stevia rebaudiana in concentrations of 25 mcg. and 50 mcg. in the growth of Streptococcus mutans. Materials and Methods: The research was experimental in vitro. It was used Stevia rebaudiana sweeteners from the brands "Stevita" and "Stevia via" on S. mutans strains ATCC 35668. The strains were seeded in Petri dishes, containing Mueller Hinton agar, and the culture was incubated, in a microaerophilic jar, in a CO2 atmosphere, for 24 and 48 hours at 35 ° C. Both of them sweeteners were diluted in distilled water, to allocate 100 ul of the solutions in 6 mm wells. of diameter. Finally, the inhibition halos were measured with a Vernier caliper. Results: For a statistical analysis a t student test was used, with a significance level (p <0.05). The minimum inhibitory concentration (MIC) of Stevia rebaudiana "Stevia Via" on the culture of S. mutans was 25 mcg. and 50 mcg. where it was found a p = 0.01. with the application of this sweetener, inhibition halos were observed in the strains of S. mutans of 11.6 mm and 12 mm. with concentrations of 25 mcg. and 50 mcg, respectively. With the sweetener from Stevia rebaudiana "Stevita", inhibition halos of 6 mm of diameter were observed in both concentrations. Conclusions: The use of the sweetener Stevia rebaudiana: Stevia Vía had an inhibitory effect on Streptococcus mutans strains. [ABSTRACT FROM AUTHOR]

La demanda por edulcorantes naturales va en aumento en el mundo, debido principalmente a los efectos secundarios que producen los edulcorantes sintéticos, lo cual ha hecho que varios países prohíban el consumo de estos. Un ejemplo es Japón, el cual prohibió el uso de edulcorantes sintéticos desde los años 70 y sustituyó la mitad del consumo de azúcar de caña por cristales de Stevia rebaudiana (Bertoni) Bertoni. Debido a la relevancia actual de S. rebaudiana, el contar con materiales adaptados a las condiciones de México es una necesidad urgente para que el cultivo se incremente en el país. En el CIRSE-INIFAP desde 2010, se trabaja con el desarrollo tecnológico de este cultivo y a partir, de 2012 se inició el proyecto de impulso a la innovación con parcelas de Morita II. Posteriormente se adquirió por parte de INIFAP material genético proveniente de Paraguay, lo cual vino a fortalecer su fuente de variabilidad genética. Esta variabilidad ha permitido establecer parcelas y realizar una selección individual de aquellos materiales que muestran un mejor comportamiento agronómico, de tal forma que en la actualidad se cuenta con una nueva varieagronómicas ampliamente superiores a los materiales criollos y a la variedad Morita II, posee hojas grandes, abundantes, y tallo muy ramificado. Florece de forma uniforme, lo cual facilita la realización del corte en el momento más oportuno (al aparecer los primeros botones florales). El promedio de rendimiento es de 7 a 9 t ha-1 año con 60 000 plantas ha-1. [ABSTRACT FROM AUTHOR]

Introduction: Introduction: medicinal plants have demonstrated therapeutic applications for treating different diseases, including chronic and degenerative diseases associated with metabolic syndrome. Objectives: to assess the weight control and the antihypertensive, antihyperglycemic and antioxidant effects of aqueous and ethanolic extracts of Stevia rebaudiana (creole variety INIFAP C01) leaves and stems cultivated in the Muna and Mocochá municipalities (Yucatán, México). Methods: aqueous and ethanolic extracts of leaves (HAMU and HEMU, respectively) and stems (TAMU and TEMU, respectively) from Muna, and aqueous and ethanolic extracts of leaves (HAMO and HEMO, respectively) and stems (TAMO and TEMO, respectively) from Mocochá were orally administered to Wistar male rats induced to metabolic syndrome. Weight, blood pressure, blood sugar levels, malondialdehyde (MDA) levels, and superoxide dismutase (SOD) levels in blood plasma were measured. Results: TAMU and HAMO samples reduced weight by 1.91 % and 1.57 %, respectively. On the other hand, HEMU and HAMU samples reduced systolic (PAS) and diastolic (PAD) blood pressure levels by 29.31-30.47 % and 36.69-36.98 %. In the glucose tolerance test (GTT) HEMU showed a reduction in blood sugar levels of 10.94 % on the first day, and of 14.83 % on day 30. TEMO and TAMO samples showed lower malondialdehyde (MDA) concentrations of 7.0 and 7.3 µM, respectively. HEMU and TEMU showed a higher superoxide dismutase (SOD) concentration of 1.29 and 1.12 U/mL, respectively. Conclusions: extracts of S. rebaudiana can help to control weight gain, to decrease blood pressure and the incidence of diabetes, and to reduce oxidative damage. [ABSTRACT FROM AUTHOR]

This paper presents the determination of antioxidant capacity and total polyphenol content in both aqueous and organic extracts of Stevia Rebaudiana stems variety Morita II. The antioxidant capacity was determined through various in vitro assays: Method 2 1,1-diphenylpicryl- hidrazyl (DPPH) assay, discoloration 2,2'-azino-bis-3-ethylbenzthiazoline-6- sulfonic acid (ABTS) assay, ferric ion reducing antioxidant power (FRAP), and total polyphenols by Folin-Ciocalteu. The results were analyzed by Person's correlation. This work was done in order to give added value to the stem of Stevia and their potential use as a source of antioxidant compounds. The results indicate that extracts of Stevia stems grown in Colombia have greater inhibitory activity of free radicals compared to reports in the literature regarding leaf and stem. Therefore it can be concluded that the stems are an accessible source of antioxidants. [ABSTRACT FROM AUTHOR]

For the production of dry leaf of Stevia rebaudiana Bertoni under the Cuban climatic conditions, it is necessary to identify the agrotechnical variables with the greatest impact on its yield. Therefore, the objective of this work was to determine the effect of pruning frequency on biomass production and steviolglycoside content. Plants of S. rebaudiana var. Morita II grown for 180 days in the stonecutter were employed. Three pruning frequencies were tested: every 30, 60 and 90 days. As a control, plants without pruning were used. The variables evaluated were the height of the plant, the number of branches per plant, the number of leaves per plant, the fresh and dry mass of the leaves and stems per plant and the percentage of flowering. In addition, the yield of dry mass per hectare was estimated and the content of steviolglycoside was determined. The results revealed that the best pruning frequency of S. rebauidiana plants was every 60 days. The results of the agronomic variables evaluated were higher than those obtained with pruning every 30 and 90 days, with the exception of the height of the plant and the percentage of flowering. With pruning every 60 days the yield was 1.19 t ha-1 and the steviolglycoside content reached 255.39 mg g-1 of dry mass. The results showed that the pruning frequency influences the production of biomass and the main components of the biomass yield, as well as the content of steviolglycosides in clarified aqueous extracts of S. rebaudiana var. Morita II grown under conditions of stonecutter. [ABSTRACT FROM AUTHOR]

Black cherry juice (Zyzygium cumini [L.] Skeels) was developed with partial and total substitution of the sugar added in its formulation by aqueous extract of stevia (Stevia rebaudiana Bert.). A response surface design was used for the preparation of the juices and their sensory acceptance (SA) and total sugar content (TS) were evaluated as response variables. The aqueous extract at 15 °C, diluted 100 times with potable water, and presented, according to sensorial criteria, a relative sweetness like a solution of sucrose 15% (w/v). The TS and SA decreased (p ≤ 0.05) with the increase in the percentage of sugar substitution, although in all cases the sensory criteria corresponded to the categories -I like it a lotand -I like it slightly-. The juices presented values of the physical and chemical indicators like this type of drinks, and high contents of total polyphenols and anthocyanins. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni is a species recognized worldwide for its medicinal properties. The objective of this work was to micropropagate Stevia plants from ex vitro explants. Shoots of plants of this specie growing at greenhouse were selected. In the in vitro establishment, the effect of disinfection time and the concentration of sodium hypochlorite on the survival of the explant were evaluated. The established explants were transferred to the multiplication culture medium, where the effect of the growth regulators (6-benzylaminopurine and indoleacetic acid) and the number of subcultures on the multiplication coefficient were determined. Then, the response of the plants in the acclimatization phase was evaluated, in comparison with plants propagated by cutting. Sodium hypochlorite at 1% allowed the disinfection of the explants with a survival of 94.5%, regardless of the time. The growth regulators did not modify the multiplication coefficient with subcultures every 15 days. It is possible to use different combinations of substrate based on zeolite and compost during the acclimatization of micropropagated plants. These developed a greater number of leaves and height than those propagated by cutting. [ABSTRACT FROM AUTHOR]

The present investigation was realized with the objective of characterizing different proportions of vermicompost:sand physical, chemical and microbiological for the production of Stevia rebaudiana Bertoni. For this, the proportions of vermicompost and sand were evaluated (V : A) 15:85, 30:70, 45:55, 60:40, 75:25 and a vermicompost substrate with agricultural soil (15:85). A completely randomized experimental design was used. The genetic material was Stevia rebaudiana Bertoni variety Morita 2. The variables evaluated in the substrates were pH, electrical conductivity, phosphorus and nitrate content, total porosity, bulk density, particle density, water retention capacity and percentage of aeration, as well as the number of bacteria and microbial groups present in the rhi- zosphere of Stevia rebaudiana Bertoni. In this last variable microbial groups were determined as: Pseudomonas, nitrogen fixing bacteria, bacilli, fungi and actinomycetes. In the plant, the physiological variables evaluated were growth rate of the crop, net assimilation rate, specific leaf area and the leaf area index. The results show a greater development of bacteria in the treatment V:A 45:55 with 1.24 x108 CFU g-1 substrate, with the actinomycetes being the ones that stand out in development with 20 x 107 CFU g-1 of substrate. In the physiological variables of the crop also the treatment V:A 45:55, stands out in the growth rate of the crop with 0.217 g m-2 day-1 and in the leaf area index with 0.088 m² m-2. [ABSTRACT FROM AUTHOR]

Black cherry juice (Syzygium cumini [L.] Skeels) was developed with partial and total substitution of the sugar added in its formulation by aqueous extract of stevia (Stevia rebaudiana Bertoni) as a sweetener. The content of total sugars and sensory acceptance of the juices decreased (p = 0.05) with the increase in the percentage of substitution of sugar by aqueous extract of stevia. The highest percentage of sensory criteria for all juices corresponded to the categories -I like it a lot- and -I like it slightly-, which confirms the possibility for replacing sugar with aqueous extract of stevia. The juices presented values of the physical and chemical indicators similar to those of this type of drinks, as well as high contents of total polyphenols and anthocyanins. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana (Bertoni) Bertoni (Asteraceae), known as "stevia", is a herbaceous plant, native from southwestern Brazil and Paraguay and cultivated in many countries of the world because contains a stevioside used as a sweetener which is not metabolized in our organism, therefore, it does not increased the glucose level in blood. It is propagated vegetatively by cuttings, a simple but not sufficient method to implement systems of mass propagation since its propagation by seeds is only done for research purposes, reason why we propose to implement the method of in vitro micropropagation by applying different concentrations of gibberellic acid and then to achieve by means of this technology a mass propagation system of high genetic and phytosanitary quality, at low costs and in quantities sufficient to supply the requirements. The mother plants used came from the Biotechnology Laboratory of the Potato and Andean Crops Institute of the National University of Trujillo. Nodal segments were used with a bud and cultivated in M & S, 1962 supplemented with 0.00, 0.50 and 1.00 ppm of gibberellic acid, which constituted the treatments. The effect of these concentrations on the parameters seedling height, number of roots and most developed root was analyzed. The analysis of variance applied did not find significant differences between these treatments and for the analyzed parameters, concluding that, at the concentrations essayed, gibberellic acid does not exert any effect, so it is possible to micropropagate S. rebaudiana by nodal segments without the presence of this phytoregulator. [ABSTRACT FROM AUTHOR]

Drought is one of the most important abiotic stresses, since it limits the production and growth of Stevia rebaudiana (Bertoni) Bertoni. The objective of the present work was to determine the effect of water stress induced by polyethylene glycol on the in vitro growth of ‘KH-IAN / VC-142’ S. rebaudiana plants. Growth variables were evaluated on in vitro plants subjected to simulated conditions of hydric stress with PEG 6000 at concentrations of 10 000, 1 000, 100, 10 and 1 ppm. In addition, a control without PEG was included. The variables plant height, root length, fresh and dry mass were negatively affected as the concentration of PEG increased. These results demonstrated the low tolerance of S. rebaudiana ‘KH-IAN / VC-142’ cultivar to hydric stress and make possible the future application on in vitro selection systems for the discrimination of cultivars genetically improved based on their tolerance to hydric stress. [ABSTRACT FROM AUTHOR]

In vitro multiplication of Stevia rebaudiana Bertoni has been described previously in different reference sources. However, the implication of the investigations carried out in the productive scale processes is not informed. The present work was carried out with the objective of establishing a strategy for the in vitro propagation of S. rebaudiana. Studies were carried out on planting, seedling multiplication as well as rooting. The effect of growth regulators at different concentrations was determined in order to increase the production of large-scale seedlings. The in vitro establishment of meristematic apices was achieved with 66.67% explants free of microbial contaminants and 83.33% survival with the use of NaOCl (1% v / v) for 5 min and a previous treatment with Previcure. The treatment with 6-BAP 0.5 + AIB 0.2 mg l-1 was selected for in vitro multiplication, and 76.67% of rooting was achieved with 0.5 mg l-1 of IBA. These results allow to propose a strategy that reduces the time of obtaining apices for the rooting to two weeks. Its approach to a scale production scheme makes it useful for its implementation in the rapid micropropagation of elite clones and the production of plant material of stevia planting on a commercial scale. [ABSTRACT FROM AUTHOR]

Stevia" Stevia rebaudiana Bertoni (Asteraceae) is highly valued worldwide for their sweetener and medicinal properties. Their demand has increased worldwide because it is recommended for feeding people who need to consume low calorie diets. Given this reality, the cultivation of S. rebaudiana nowadays covers large areas and it is necessary vigorous and uniform plants, whereby the application of asexual propagation by cuttings is a good alternative. With the necessity to obtain rooted cuttings of S. rebaudiana Bertoni, “stevia", we took as objective to determine the effect of increasing doses of indolebutyric acid on cuttings. For that, we selected mother plants obtained from plant tissue cultures of the Biotechnology Laboratory of the Institute of Potato and Andean Crops. Once we obtained the cuttings, they were transported to the greenhouse for planting in quartz sand, with previous treatment with IBA powder, using different concentrations (0.0, 0.5 and 1.0 ppm). Statistically significant differences were found, with T3 showing the greatest height, number of roots and root length. It is concluded that concentration of 1 ppm of IBA has a positive effect on rooting cuttings of S. rebaudiana . [ABSTRACT FROM AUTHOR]

The genus Stevia Cav. (Asteraceae) consists of about 200 species in the Americas. Stevia rebaudiana (Bertoni) Bertoni, originally from Paraguay, is the only cultivated species. It has widely been studied chemically, because of the active compounds found in the leaves. However, there is controversy about its reproductive system, as some authors consider it an obligate apomict, while others a sexually reproducing species. In order to clarify this issue: the megasporogenesis, megagametogenesis, floral phenology, pollen viability, and stigmatic receptivity were studied in three ecotypes, under self-pollination and cross-pollination. According to our results, the plants reproduce sexually and have a self-incompatibility system that prevents self-fertilization. [ABSTRACT FROM AUTHOR]

The consumption of gummy candy is widespread among people of different ages but mainly by children. The formulation of this product requires sugar that contributes to their flavor and consistency, but with the undesirable effect of increase its glycemic index and its calories from simple sugars; it is known that consumption of products with these last two characteristics are related to childhood obesity, which is a worldwide growing disease. Stevia rebaudiana is a plant that naturally contains glycosides with high sweetening power and it is considered safe for consumption. Therefore the aim of this work was to develop a gummy candy reduced in calories by replacing sugar with Stevia rebaudiana B., and analyzes its texture and acceptability. Gummy candy were prepared with different percentage of sugar reduction (-20, -40, -60, -80 and -100%) and a product control (100% sugar); gummy elasticity was assess by displacement and maximum deformation, whereas resistance was evaluated by breaking strength; those gummies with better elasticity and resistance parameters underwent proximate analysis and sensory evaluations with a unstructured scale applied to 90 school children aged between 6 and 10 years old. A gummy candy reduced in calories with 60% sugar substitution with S. rebaudiana was developed; the level of satisfaction in school children was statistically the same respect to the gummy made of 100% sugar (p <0.05). [ABSTRACT FROM AUTHOR]

Stevia rebaudiana leaves and their glycosides have been recently and significantly used so important as sweeteners. However, it has been reported an antihyperglycemic effect of the extract and a glycoside. The aim of this study was to quantify S. rebaudiana glycosides, assess cytotoxicity of the extract and its acute and chronic effect on blood glucose in animal models and in human. The glycosides of the Morita II and Criolla extract were quantified by HPLC, using a C18 column (250 mm x 4.6 mm and particle size of 5 uM) with UV detection at 210 nm, mobile phase of acetonitrile/sodium phosphate buffer 10 mmol/L, pH 2.6 (32:68 v/v). Cytotoxicity study was performed in Vero cells, whereas an intraperitoneal glucose tolerance test (IPGTT) and a chronic consumption assay (4 weeks) were executed in an animal model of diabetes; finally the glycemic index (G.I.) was determined in healthy individuals. The glycoside content is higher in the Morita variety II although both had a CC50 >300 µg/mL. The areas under the curve of the IPGTT and fasting glucose of the animals were not significantly different (p> 0.05) and the I.G. extract was 11.11 %, which classifies the extract as low I.G. The extract of S. rebaudiana Morita II has a low glycemic index and, in the doses tested, is not cytotoxic nor has acute or chronic effect on blood sugar, which makes it a safe sweetener. [ABSTRACT FROM AUTHOR]

This review had as objective to gather and to analyze the information about the historical origin of the consumption of Stevia rebaudiana, its chemical composition, benefits to the health, toxicity and use. This plant in its natural form is 15 times sweeter than sucrose and the extract is 100 to 300 times sweeter. The main sweet component of the leaves of this plant is a glucoside named stevioside, they are also present other, but in smaller concentrations, like they are the rebaudoside A, B, C, D, and F, steviolbioside and dulcoside A. The extraction of the sweetener substances from of the dry leaf of estevia is easily carried out with water or ethanol, followed by a purification process. The Expert's Committee in Alimentary Preservatives together with FAO and WHO established an Acceptable Daily Ingest for the stevioside from 0 2 mg/kg of corporal weight, based on the toxicity studies that demonstrate that stevia extracts and the stevioside do not present acute toxicity, neither carcinogenic and/or teratogenic effects. On the other hand, the sweetener substances of stevia are highly soluble in water, stable to heat (200 °C) and to a wide range of pH values (3 9), which allows to be used in a wide range of nutritional products. [ABSTRACT FROM AUTHOR]

The adjustment of an efficient protocol of somatic embryogenesis in Stevia rebaudiana Bertoni to support programs of genetic breeding by genetic transformation is necessary. Few results are registered up to the moment in this species. The objective of this work was to obtain calli with embryogenic structures from clones of Stevia in vitro plants. Different variables were studied for the formation of calli: explants type, incubation conditions and genotype influences. Culture medium MS with different growth regulators (2,4-D; 6-BAP; TDZ) was used. These were used alone or in combination. Calli were multiplied in the best culture media. Afterwards they were subcultured to culture medium containing 2,4-D or TDZ with 40 and 60 g·l-1 of sucrose to induce proembryogenic mass formation. Calli formation was achieved after 45 days of culture in darkness and in culture media with 2.26 μM 2,4-D and 2.22 μM 6-BAP or 1.13 μM 2,4-D and 0.45 μM of TDZ. Foliar explants of in vitro plants of Stevia were used. Multiplication was achieved in the same culture media for calli formation. The largest amount of calli with development of proembryogenic mass was obtained when subcultures to culture medium with 0.45 μM 2,4-D adding 40 g·l-1 of sucrose was carried out after 45-50 days of culture. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni, Asteraceae family (2n = 22), is a plant native from Paraguay, it has in leaves tissues a high production of some substances with strong edulcorant power, getting to be 320 times more sweet than sugar. Stevia was introduced, in Department of Antioquia, Colombia, at different times from diverse places. Its cultivation has been spread in the Department, additionally is an alternative for illicit cultivated crops substitution. AFLP marker were generated from genomic DNA of two reference varieties ('Morita' and 'Bertoni') and samples from fields crops located in different regions of Department of Antioquia. Ten AFLP primer combinations revealed 923 bands and 39.22% polymorphism. Dice coefficient similarity analysis show differences between both 'Morita' and 'Bertoni' varieties. Primer combination EcoRI-AGG/ Tru 9I-ATG, was able to identify every of two cultivars, and established two groups for Department of Antioquia Stevia varieties. Samples from Támesis, Andes, Jericó, San José del Nus and Santa Fe de Antioquia localities were grouped within 'Morita' cultivar and samples from Fredonia, Cisneros localities and University of Antioquia laboratories were grouped within 'Bertoni' variety. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana is a Paraguayan plant which can produce diterpene glycosides that are 300 times sweeter than sugar and are low caloric compounds, besides have other therapeutic properties. Due to the advantages of this plant, the aim of the present work was to evaluate different extraction and downstream methods to obtain diterpene glycosides crystals, with good organolepthic properties. The unit operations used were: to free from grease of plan material, solvent lixiviation, salt and pH precipitation, membrane filtration (UF), and sorption processes. To confirm the presence of diterpene glycosides in every steps and identify them, we performed indirect colorimetric method (DNS), spectroscopic method (IR) and chromatographic assays (TLC, HPLC). From experimental design results, we could identify the critical steps of downstream and discard operations with low efficiency. We established a process to purify a mixture of sweetness and the product was white, very sweet, odorless and the flavor was intense and durable. Results suggest the mayor glycoside in the final product was rebaudioside A. [ABSTRACT FROM AUTHOR]

The distribution of cultivations in the world is restricted by the climatic limits, for defect or for excess of vital necessities for the individuals that conform the different biotypes. Since sow is made, plants are subjected to asynchronous variations of component elements of climate and it is the climate the main decisive factor of probability of success of cultivation. The objective of this work was the delimitation of the Argentinean geographical area where it is possible the economic production of Stevia rebaudiana Bertoni that was supposed to overcome widely the area embraced by the bioclimatic zone. Since extracted data of the Climatic Statistics published by the National Meteorological Service it was sketched the climatic indexes that define the agroclimatic zone of the specie for the period 1961-1990 for meteorological and agrometeorological stations distributed in the country. Then, all maps corresponding to each one of the climatic indexes were elaborated and the resulting map of the overlapping of all previous ones defined the agroclimatic zone of the Stevia rebaudiana. Later, geographical areas embraced by the bioclimatic and the agroclimatic zones were compared. [ABSTRACT FROM AUTHOR]

The estimation of the leaf area in the agricultural sciences is fundamental because it is a factor that is involved in different physiological processes. Therefore, it is necessary to make estimates from allometric models that consider the assumptions and statistical criteria needed to extract or infer useful information from them. Numerous studies have proposed models in different cultivars to estimate the leaf area, however, many do not critically evaluate the suitability of the assumptions of the model, therefore, they end up being biased models. In consideration of the above, this study describes a methodology that allows the non-destructive estimation of the leaf area through statistical strategies applied to tropical crops that is demonstrated with practical examples developed in Stevia rebaudiana. [ABSTRACT FROM AUTHOR]

The genus Stevia (Stevia rebaudiana Bert), is native to the North of Paraguay, where it has been used by the native Indians in teas and food preparations; Its main properties are sweetener and medicinal. The species contains low calorie diterpene glycosides, whose sweetening power is more powerful than sucrose, its content may vary depending on the genotype and environmental and growing conditions. The study was carried out at the facilities of the University of Córdoba-Colombia, this study consisted of a completely random design (AxBxC+2), where the effect of the increase in the concentration of CO2 in the biomass production of two experimental clones of Stevia, in the variables of dry mass and leaf area. The most relevant results indicated that an increase in the concentration of CO2 to 800 ppm showed a favorable effect on the variables evaluated, with clone 16 standing out with 1403.981 cm2 over clone 04 with 1115.682 cm2 for the leaf area variable. Clone 16 presented the best response when the CO2 concentration increased to 800 ppm. The increase in the concentration to 1200 ppm had repercussions on the variables causing a decrease in the accumulation of biomass. [ABSTRACT FROM AUTHOR]

Para evaluar la respuesta de la Stevia rebaudiana frente a la aplicación de N, P, K, Ca, Mg y S se llevó a cabo un experimento donde se determinó su efecto sobre el aumento progresivo de biomasa y absorbancia de nutrientes en las diferentes partes de la plantas. El experimento se realizó en el invernadero y laboratorio de suelos de la Facultad de Ciencias Agrícolas de la Universidad de Córdoba, para este se usó un diseño en completo al azar (DCA), 7 tratamientos, y 4 repeticiones por tratamiento, completando así 28 unidades experimentales. Los tratamientos aplicados fueron: 0,0 – 140 – 420 – 840 – 1400 – 1680 – 2100 kg ha-1 después de 20 días de establecido el cultivo. Para determinar el contenido masa húmeda y seca, y área foliar, además del contenido de macronutrientes en los hojas. Los resultados obtenidos demuestran que para la masa seca de hojas la dosis optima de la mezcla de nutrientes fue 283 7 kg ha-1; En esta cantidad existían de N disponible, P2O5 y K2O, 74,2; 23,2 y 54,5 7 kg ha-1; para el peso seco del tallo la dosis optima fue de 250 7 kg ha-1. En esta cantidad existían de N disponible, P2O5 y K2O, 65,5; 20,5 y 48,2 kg ha-1 y el área foliar indicó que la dosis optima fue de 55,7 kg ha-1. En esta cantidad existían de N disponible, P2O5 y K2O, 14,59; 4,5 y 10,7 kg ha-1. [ABSTRACT FROM AUTHOR]