Stevia Rebaudiana Extracts Research Articles

Histological and Immunohistochemical Study of the Effect of Stevia Rebaudiana Extract on the Cerebral Cortex of High Fat Diet-fed Adult Male Albino Rat

Histological and Immunohistochemical Study of the Effect of Stevia Rebaudiana Extract on the Cerebral Cortex of High Fat Diet-fed Adult Male Albino Rat

Application of natural sweetener Stevia rebaudiana in the medical field

Steviol glycoside sweeteners have been isolated and produced for hundreds of years in Bertoni, a South American Asteraceae plant prized for its sweetness. Stevia is becoming more popular among consumers and food manufacturers as a result of diabetes, rising obesity rates, and other related comorbidities, as well as global public policies calling for a reduction in intake of sugar to help control these issues. Low-calorie as well as no-calorie sweeteners, such as Stevia, have this appeal because they are plant-based, have no calories, and have a sugary flavour that is 50 to 350 times sweeter than table sugar, making them an excellent as well as suitable choice for use in foods as well as beverages with lower sugar and calorie content. This plant yields steviol glycoside sweeteners, which are isolated and processed. Current studies on Stevia rebaudiana extract, metabolism, tolerable intake, and safety, steviol glycoside extraction and purification, side effects, as well as the toxicity of Stevia extract are discussed in detail.

Herb Stevia Rebaudiana’s Functionalities, Safety, and Applications: A Review

Herb Stevia rebaudiana extract, also known as sweetleaf, was originally discovered for its sweetening function. Researches show that this plant extract is embedded with multiple functionalities such as antioxidant, antidiabetics, anti-inflammation, and antimicrobial. This review article helps re-arrange the scientific affairs of those stevia extract’s functions. Sweetness indexes of steviol glycosides were summarized together for comparison while various in vitro, in vivo approaches were reviewed to quantify those functions’ capacities and to depict the related mechanism. The regulation of steviol glycoside compounds such as rebaudioside A was established by global authorities such as US Food and Drug Administration (FDA) and Joint FAO/ WHO Expert Committee (JECFA) to ensure the safety endorsement prior to commercialization. In applications, we first used sentiment analysis to catch a good command of the stevia-containing products’ market performance. Then, we investigated the product development progress of stevia-containing food products in the categories of beverage, bakery, dairy, and confectionery. Those stevia-containing food consumer goods can be acceptable by certain customers.

Biosynthesis of silver nanoparticles using extracts of Stevia rebaudiana and evaluation of antibacterial activity.

The present study reveals a simple, non-toxic and eco-friendly method for the "green" synthesis of Ag-NPs using hydroponic and soil medicinal plant Stevia rebaudiana extracts, the characterization of biosynthesized nanoparticles, as well as the evaluation of their antibacterial activity. Transmission electronic microscopy (TEM) and Dynamic Light Scattering (DLS) analysis confirmed that biosynthesized Ag-NPs are in the nano-size range (50-100nm) and have irregular morphology. Biogenic NPs demonstrate antibacterial activity against Escherichia coliBW 25,113, Enterococcus hirae ATCC 9790, and Staphylococcus aureus MDC 5233. The results showed a more pronounced antibacterial effect on E. coli growth rate, in comparison with Gram-positive bacteria, which is linked to the differences in the structure of bacterial cell wall. Moreover, the Ag-NPs not only suppressed the growth of bacteria but also changed the energy-dependent H+-fluxes across the bacterial membrane. The change of H+-fluxes in presence of H+-translocating systems inhibitor, N,N'-dicyclohexylcarbodiimide (DCCD), proves the effect of Ag-NPs on the structure and permeability of the bacterial membrane. Overall, our findings indicate that the Ag-NPs synthesized by medicinal plant Stevia extracts may be an excellent candidate as an alternative to antibiotics against the tested bacteria.

Herbal formuLation of Azadirachta indica and Stevia rebaudiana and Its Anti-inflammatory and Anti-Diabetic Activity

Introduction: Azadirachta indica, a natural herb also called Neem, and its seed extract has various medicinal uses. Neem also possesses notable insecticidal and pesticide activities. On the other hand, Stevia rebaudiana extract has alpha amylase glycosidase inhibitory activity, which contrasts with traditional wheat bread. This last plant can also regulate blood glucose levels, and prevent hypertension and caries.
 Aim: This study aimed to analyse the anti-diabetic and anti-inflammatory activities of Azadirachta indica and stevia rebaudiana.
 Materials and Methods: 2.5 g from Azadirachta indica and Stevia rebaudiana plants mixed with 100 mL of distilled water were boiled. The final extract was then filtered using Whatman filter paper. Spearman correlation analysis was done by SPSS. Positive correlation analysis level of significance was set as r=1.
 Results: The anti-diabetic activity and anti-inflammatory activities of Azadirachta indica and Stevia rebaudiana extracts showed positive spearman correlations (r = 1). Both activities happen in a dose-dependent manner, being higher with the increasing of the concentration and of the absorbance values.
 Conclusion: Through this study, it was possible to conclude that Azadirachta indica and Stevia rebaudiana have great anti-inflammatory and anti-diabetic activities and can be used as a possible alternative drug for attenuating inflammation and preventing diabetic complications.

Herbal Extracts as Potential Antioxidant, Anti-Aging, Anti-Inflammatory, and Whitening Cosmeceutical Ingredients.

The aim of this research was to investigate and compare the antioxidant, anti-tyrosinase, anti-aging, and anti-inflammatory activities of 16 herbal extracts for topical application in cosmetic/cosmeceutical products. Herbal plant materials were extracted by infusion in boiled water for 15 min. The total phenolic content and total flavonoid content of each extract were investigated by the Folin-Ciocalteu and aluminum chloride methods, respectively. Antioxidant activities were investigated using 2,2'-diphenyl-1-picrylhydrazyl and a ferric reducing antioxidant power assay. Anti-tyrosinase and anti-aging activities were investigated using an in vitro enzymatic-spectrophotometric method. Anti-inflammatory activities were investigated using an enzyme-linked immunosorbent assay. The findings show that the Stevia rebaudiana extract has the most significant levels of both phenols and flavonoids (p<0.05). The S. rebaudiana, Rosa damascene, and Phyllanthus emblica extracts possessed the most significant antioxidant activities (p<0.05) and a promising whitening effect with moderate anti-tyrosinase activities. Furthermore, the Echinacea purpurea extract possessed the most significant anti-collagenase (78.5±0.0 %), anti-elastase (69.0±1.4 %), and anti-hyaluronidase activity (64.2±0.3 %). The Morus alba extract possessed the most significant anti-inflammatory activity since it could inhibit the secretion of interleukin-6 and tumor necrosis factor-α (p<0.05). Therefore, these herbal extracts have promising skin benefits and have potential for use as active ingredients in cosmetic/cosmeceutical products.

Morphological, structural and cytotoxic behavior of starch/silver nanocomposites with synthesized silver nanoparticles using Stevia rebaudiana extracts

The synthesis of silver nanoparticles (AgNPs) using a Stevia rebaudiana aqueous extract and their dispersion in starch in order to obtain starch/AgNps nanocomposites are shown in this study. The AgNPs and the starch/AgNPs nanocomposites have been characterized by ultraviolet–visible spectroscopy, optical microscopy, high-resolution transmission electron microscopy, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis. Furthermore, the interaction of starch/AgNPs nanocomposites with a MCF-7 breast cancer cell line is analyzed. AgNPs with an average size around 15–20 nm have been obtained. starch/AgNPs nanocomposite morphology changes with the content of silver (3, 5 and 8 mM), from totally separated and dispersed nanoparticles to ribbon-type morphology. The diffraction pattern of the starch/AgNPs-3 nanocomposite indicates the formation of silver chloride nanoparticles (AgClNPs). A cytotoxic behavior of starch/AgNPs-3 nanocomposite on MCF-7 cancer cells with less damage to normal cells is observed. Hence, the high dispersion of the AgNPs or AgClNPs in starch could be influencing the selective cytotoxic behavior. Thus, this study proposes the generation of biocompatible composite materials, with AgNPs immobilized on starch. These materials have selective action against breast cancer cells, where the selectivity is controlled through the AgNPs dispersion on the biopolymer.

Formulation and Optimization by Experimental Design of Dairy Dessert Based on Lupinus albus L. and Stevia rebaudiana Extracts

The approximate chemical composition and amino acid profile of Lupinus albus seeds were studied. Protein content of lupin and lupin mlik seeds; 45.2(±0.09) g/100g and 7.25(±0.08) g/100g, respectively; fat content 9.04(±.14) g/100g and 6.01(±0.06) g/100g, respectively. Lupine seeds rich in leucine, lysine and proline: 4.168; 4.059 and 2.620 (g/100 g) respectively. This work made it possible, using the experimental design method, to carry out eighteen trials of dessert cream formulated with different concentrations of lupin milk. The reduction of the quantity of sucrose used to 7.15% instead of 11% and the use of 3.85% Stevia rebaudiana extract have resulted in a dessert cream that is lighter in sugar. The chemical properties of the formulated tests revealed a high protein content ranging from 8.36 to 16.25 g/100 g and a fat content ranging from 3.50 to 4.92 g/100 g. Finally an optimal formula was developed with good sensory characteristics.

Study of antihyperglycaemic activity in streptozotocin induced diabetic mice and antioxidant activities of medicinal plant extracts

Some extracts of medicinal plants have demonstrated potential benefits in treatment of different diseases for centuries such as antihyperglycemic, antioxidant, anti-inflammatory, antibacterial. The purpose of this study is to evaluate the effect of extracts from several herbal plants, such as Gymnema sylvestre, Stevia rebaudiana, Cinnamomum cassia, Zea may, Ocimum basilicumon blood glucose level in streptozotocin (STZ) induced diabetic miceand to offer scientific proofs for the identified antihyperglycemic effect by investigating on mechanismsof the most effective extract. The results proved that diabetic mice treated with 70% ethanol extracts of Gymnema sylvestre leaves and Stevia rebaudiana leaves showed significant reduction of the blood glucose levels at a dose of 500 mg/kg body weight when compared to control (p&lt;0,05). Antihyperglycemic activity of Gymnema sylvestre (57,68%) and Stevia rebaudiana extracts (54,93%) were significantly higher than other extracts. The inhibition of α-amylase and α-glucosidase activity of Gymnema sylvestreand, Stevia rebaudiana extracts were carried out in vitro. The result demonstrated that these Gymnema sylvestre and Stevia rebaudiana extracts exerted significant inhibition and specific on intestinal α-amylase and α-glucosidases activities. Using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay showed that Gymnema sylvestre and Stevia rebaudiana extracts exhibited relatively low antioxidant activity with the concentration of a sample required for 50% scavenging of the DPPH free radical of 115,88 ± 1,16 µg/ml and 160,27 ± 2,01 µg/mlcompared to vitamin C (49,16 ± 1,26 µg/ml).

Development of nopal-pineapple marmalade formulated with stevia aqueous extract: effect on physicochemical properties, inhibition of α-amylase, and glycemia response.

Introduction: Stevia rebaudiana extracts can be used as a sweetener due to their glycoside content: specifically stevioside and rebaudioside. Both compounds have adequate pharmacological characteristics for human consumption. Objective: the aim of this study was to standardize the formulation of marmalades using nopal-pineapple-stevia aqueous extract ratios. Methods: the products were evaluated to determine their physicochemical properties, in vitro inhibition of α-amylase and glycemia in healthy volunteers. Storage study was conducted for 20 days at room temperature 23-30 °C and relative humidity 80-85%. Results: incorporation of stevia significantly modified physicochemical properties like °Brix, color and flow index. After storage, the presence of molds and bacteria were not detected. Sensory evaluation indicated that marmalade with 50% stevia replacement was equally accepted as marmalade with sucrose. Marmalade with 50 and 100% of stevia inhibited 35.89 and 38.50% of the α-amylase activity. After an intake of 30 g, it seems that marmalades with stevia had a significant effect on the glycemia of the volunteers. Conclusions: however, further studies with larger doses of nopal-pineapple-stevia marmalade and consumed for longer in both healthy volunteers and patients with diabetes are needed to achieve results that are more precise.

Influence of Extraction Methods on the Yield of Steviol Glycosides and Antioxidants in Stevia rebaudiana Extracts.

This study evaluated the application of ultrasound techniques and microwave energy, compared to conventional extraction methods (high temperatures at atmospheric pressure), for the solid-liquid extraction of steviol glycosides (sweeteners) and antioxidants (total phenols, flavonoids and antioxidant capacity) from dehydrated Stevia leaves. Different temperatures (from 50 to 100 °C), times (from 1 to 40 min) and microwave powers (1.98 and 3.30 W/g extract) were used. There was a great difference in the resulting yields according to the treatments applied. Steviol glycosides and antioxidants were negatively correlated; therefore, there is no single treatment suitable for obtaining the highest yield in both groups of compounds simultaneously. The greatest yield of steviol glycosides was obtained with microwave energy (3.30 W/g extract, 2 min), whereas, the conventional method (90 °C, 1 min) was the most suitable for antioxidant extraction. Consequently, the best process depends on the subsequent use (sweetener or antioxidant) of the aqueous extract of Stevia leaves.

Mould growth and mycotoxin production as affected by Equisetum arvense and Stevia rebaudiana extracts

Cereals are very important for human and animal diet. However, agricultural products can be contaminated by moulds and their mycotoxins. On the other hand, natural plant products with antimicrobial properties could be a possibility to control mycotoxigenic fungi in foods and feeds. In this study, Equisetum arvense and Stevia rebaudiana extracts were tested for their efficacy against a range of mycotoxigenic fungi. Maize agar medium (MAM 2%) was used for this study and E. arvense and S. rebaudiana extracts were added at different concentrations (1–3%) under different water activity (aw) levels (0.85–0.95). Six mycotoxigenic moulds were inoculated and incubated at different temperatures (15–30 °C) during 21 days. In general, no growth was observed with E. arvense extract at 3% in all studied conditions for all isolates. However, with S. rebaudiana extract at 2–3%, growth was not significantly decreased (p < 0.05) in most of the cases. Finally, in terms of toxin production, results were not conclusive. The use of E. arvense extracts as antifungals and antimycotoxigenics and their application should be further explored.