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So far, the use of artificial low‐calorie sweeteners, like sucralose, saccharin, and so on, to replace the conventional‐based sugars has not succeeded due to the long‐term adverse health effects, for example, hypertension, and not well‐known safety stand. In this review, we discussed the next generation SvGl (rebaudioside M [Reb M]), their biosynthetic pathway in plant, high‐yield production via microbial fermentation and enzyme engineering, physicochemical properties, taste modification, kinetic metabolism, application in food and beverages, safety and toxicological evaluation, regulation and dosage recommendation, and health benefits. In stevia, the biosynthesis of stevia glycosides, especially Reb M, is derived from the bifurcation of the pathway leading to gibberellin, followed by subsequent enzymatic modification of rubusoside. Reb M is more economically produced via microbial fermentation of modified yeast Yarrowia lipolytica and enzymatic bioconversion of rebaudioside A (Reb A) or Reb E. Reb M can serve as a suitable alternative to the conventional‐based sugars. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana (Bertoni) is a valuable sweetener plant whose sweetness primarily derives from steviol glycosides (SGs), especially rebaudioside A (RA). Polyploidization has the potential to enhance the content of active ingredients in medicinal plants, making this strategy a promising avenue for genetic improvement. However, the underlying regulatory mechanisms that contribute to the fluctuating SGs content between autotetraploid and diploid stevia remain unclear. In this study, we employed metabolic analysis to identify 916 differentially accumulated metabolites (DAMs), with the majority, specifically terpenoids, flavonoids, and lipids, exhibiting upregulation due to polyploidization. Notably, the content of stevia's signature metabolite SGs (including RA, steviolbioside, and rebaudioside C), along with their precursor steviol, increased significantly after polyploidization. Furthermore, a comprehensive analysis of the transcriptome and metabolome revealed that the majority of differentially expressed genes (DEGs) involved in the SG-synthesis pathway (ent-KAH, ent-KS1, UGT73E1, UGT74G1, UGT76G1, UGT85C2, and UGT91D2) were upregulated in autotetraploid stevia, and these DEGs exhibited a positive correlation with the polyploidization-enhanced SGs. Additionally, multi-omics network analysis indicated that several transcription factor families (such as five NACs, four WRKYs, three MYBs, eight bHLHs, and three AP2/ERFs), various transporter genes (four ABC transporters, three triose-phosphate transporters, and two sugar efflux transporters for intercellular exchange), as well as microorganisms (including Ceratobasidium and Flavobacterium) were positively correlated with the accumulation of RA and steviol. Overall, our results indicate the presence of a regulatory circuit orchestrated by polyploidization, which recruits beneficial rhizosphere microbes and modulates the expression of genes associated with SG biosynthesis, ultimately enhancing the SG content in stevia. This finding will provide new insights for promoting the propagation and industrial development of stevia. [ABSTRACT FROM AUTHOR]

Chemical preservatives commonly used in food preservation often pose health risks and contribute to bacterial resistance, prompting the search for safer alternatives from natural sources. Stevia rebaudiana Bertoni leaves are well-known for their role as natural sweeteners and sugar substitutes in both culinary and medicinal applications. Additionally, their extracts exhibit diverse biological activities, such as antidiabetic, antibacterial and antioxidant properties, and have previously been confirmed for use in food preservation. Nevertheless, limited research has explored the potential of leaf residues, which are plentiful wastes from steviol glycoside extraction. These residues might still retain valuable bioactive compounds suitable for food preservation, emphasizing the need for additional investigation. Therefore, in this study, stevia leaf residues were subjected to ethanol (RE), a 50 % ethanol/water mixture (REW), and hot water (RW) extraction, and the antibacterial and antioxidant properties of 3 distinct extracts were examined. Evaluation of antibacterial activity against Staphylococcus aureus revealed significant inhibition zones for all extracts, with the REW extract exhibiting the highest efficacy, reaching up to 25.58 ± 2.54 mm. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 0.0125 mg per spot and 0.2 mg per spot, respectively, were recorded for the most effective extract (REW), indicating a bacteriostatic effect. Quantification of total phenolic content (TPC) and total flavonoid content (TFC) revealed a strong correlation between phenolic compounds and the tested biological activities, antibacterial and DPPH radical scavenging. Furthermore, HPLC Orbitrap MS analysis identified 6 compounds in the extract: 1 phenolic acid, 4 flavonoids and 1 fatty amide. These identified compounds may be responsible for the observed biological activities of the stevia leaf residue extract. The results confirm the retained potential of stevia leaf residue extracts as sources of natural preservatives in the food industry, offering both antimicrobial and antioxidant benefits. [ABSTRACT FROM AUTHOR]

Stevia plant is one of the most important medicinal plants used to control diabetes due to its sweetening properties and low calories. Stevia is cultivated in many parts of the world, and to increase its sweetening properties, the effects of many different factors have been tested on this plant. In this research, we investigated the effect of elements related to metal oxidants on the induction of molecular levels and transcription. Thus, the activity of 3 key genes named CPPS, HDS, and GGDPS in response to six different metal oxidants named Cro3, Pbo, Fe2O3, Ag2O, Bao, and Tio2 was carried out in this research. The results showed that the increased concentration of metal oxides, especially Fe2O3 and TiO2, escalates gene expression in the biosynthesis of sweeteners extracted from stevia leaves. Also, related to all treatments, the higher the concentration, the higher the gene expression. Among all metal oxide treatments, Pbo and Bao resulted in low gene expression for CPPS, HDS, and GGDPS genes. On the other side, control showed the lowest expression regarding all three surveyed genes, indicating that using metal oxides can achieve higher production of sweeteners in stevia plants. The results of this research determined that physiological characteristics are affected by metal oxide treatments. Also, the expression of genes effective in the production of steviol glycosides, which is one of the important sweetening factors of this plant in the leaves, increases under the influence of these treatments. As a result, it can be said that the use of these treatments can have an increasing effect on the amount of sweetening of the plant. [ABSTRACT FROM AUTHOR]

Introduction: Osteosarcoma (OS) is a rare and aggressive form of bone cancer that primarily affects the long bones of the body, such as the arms and legs. It is characterized by the uncontrolled growth of malignant cells in the bone tissue, leading to the formation of abnormal and painful bone masses. Steviol glycosides have been widely used as natural noncalorie sweeteners and are the collective name of the sweet substances found naturally in the plant Stevia rebaudiana, which is commonly called Stevia. Our study aimed to analyze the anticancer activity of Stevioside in OS. Materials and Methods: Stevioside was applied to OS cells, and the levels of Bcl xL, Bcl-2, and Bax were then estimated. The results of three separate studies, each carried out in triplicate, were expressed as the mean ± standard errors of the mean (SEM). One-way ANOVA was used for statistical analysis. Results: The findings showed that the effect of Stevioside on sarcoma osteogenic cells with mean ± SEM as 0.74 ± 0.05, 0.69 ± 0.09, 0.46 ± 0.09 for Bcl-xL gene, 0.98 ± 0.06, 0.58 ± 0.07, 0.5 ± 0.07 for Bcl-2 gene, and 1.2 ± 0.08, 1.45 ± 0.11, 1.67 ± 0.12 for Bax gene, respectively, when treated with untreated control cells. Conclusion: The study concludes its action against bone OS cells was significant with apoptotic induction. Stevia has a wide range of health benefits as well as being a plant-based diet it has less of side effects and promoting features even by intaking it daily along with other medicines.

Introduction and Background: Diabetes is a chronic metabolic disease characterized by elevated blood glucose levels and is one of the main global health concerns. Synthetic sugar substrate has many side effects such as leukemia, bladder cancer, hepatotoxicity, breast cancer, headache, and brain toxicity. The WHO and FDA has recently banned some of the synthetic sugar alternatives due to their carcinogenic effects. Objective and Methodology: Therefore, the main objective of the current study was to investigate the safety and binding affinity of Stevioside with Glucose Transpoter-4 (GLUT-4), Akt, Insulin Receptor (IR) and Insulin Receptor Substrate-1 (IRS-1) to confirmed that Stevioside is one the potent natural sweetener/drug for diabetes. This study delves into the molecular interaction between Stevioside and key diabetic proteins: GLUT-4, Akt, IR and IRS-1. A precise molecular docking approach was used to simulate the binding affinity of Stevioside to these proteins. The pharmacokinetic properties of the molecule should be taken into consideration as important variables throughout the virtual screening process. Results: The result of active site analysis of GLUT-4, Akt, IR and IRS-1 showed a zone of 2158.359 Ų, 579.259 Ų, 762.651 Ų, and 152.167 Ų and a volume of 2765.094 ų, 355.567 ų, 686.806 ų, and 116.874 ų, respectively. Docking analysis of the Stevioside compound showed the highest docking energy with scores of -9.9 with GLUT-4, -6.7 with Akt, -8.0 with IR and -8.8 with IRS-1. Studies indicated that it remains undigested by stomach acids and enzymes and is not absorbed in the upper small intestine. Further, tests revealed no hepatotoxicity, AMES toxicity, or skin sensitivity, making it a promising candidate for safe consumption as drug metabolism. Conclusion and Recommendations: Instead of other sugar alternatives, Stevioside will help diabetic patients with a lower chance of infections, lowered blood pressure/blood sugar, and increased glucose uptake in diabetic muscles. Stevioside is a natural sweetener, and the current study recommends its usage in various dietary products for diabetic patients. [ABSTRACT FROM AUTHOR]

Background. Iron, zinc, copper, and chromium status is often disturbed in the course of metabolic diseases, including type 2 diabetes mellitus. This brings about alterations and abnormalities in the absorption, distribution, and excretion of certain elements and in turn, is responsible for further progression of the disease. This study aimed to evaluate the effects of a high-fat diet supplemented with a combination of steviol glycosides (stevioside or rebaudioside A), L-arginine (two levels), and chromium(III) (two levels) on trace element (Fe, Zn, Cu, Cr) content in the liver and kidneys of rats with induced type 2 diabetes. Materials and methods. The experiment was carried out on 110 rats, of which 100 were induced with mild type 2 diabetes with high-fat diet feeding and intraperitoneal streptozotocin injection. Afterward, the diabetic animals were divided into 10 groups and received either a high-fat diet, a high-fat diet with metformin (0.3%), or a high-fat diet supplemented with a combination of steviol glycosides (stevioside or rebaudioside A, 2.5%), L-arginine (2% or 4%), and chromium(III) (0.001% or 0.005%) for 6 weeks. The Fe, Zn, Cu, and Cr content in tissues was determined after microwave mineralization of samples and then using the atomic absorption spectroscopy (AAS) method. Results. Induced hyperglycemia disturbed several tissular trace element levels in the liver and kidneys of type 2 diabetic rats. Combined supplementary factors, such as the type of steviol glycoside or levels of either L-arginine and/or chromium(III), were able to mitigate some alterations of trace elements, while some particular combinations of experimental factors even increased certain trace elements content in the analyzed internal organs of rats. Conclusions. Mild hyperglycemia disturbs trace element (Zn, Cr) balance by shifting trace element concentrations in the critical organs (liver, kidneys) in type 2 diabetes rats. Supplementary agents can independently, or in certain combinations, mitigate some trace element alterations or even cause further changes in their concentrations in the liver or the kidneys. The metabolic significance of these alterations is not fully understood and warrants further studies. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni is a perennial herb, widely used as a natural sweetener around the globe. The key compounds responsible for its sweetness includes stevioside and rebaudioside-A. In order to improve these steviol glycosides, the present study was initiated to study the effect of induced mutagenesis on growth parameters, steviol glycosides and nuclear DNA content in Stevia rebaudiana Bertoni using ten doses of gamma-rays (5-100 kR). Healthy seeds of 'Madhuguna' variety of Stevia rebaudiana Bertoni developed and maintained at stevia breeding farm, Agrotechnology division, CSIR-Institute of Himalayan Bioresource Technology, Palampur (HP), India were irradiated with ten doses of gamma rays (600 seeds each/dose) ranging from 5 kR to 100 kR (i.e., 5, 10, 15, 20, 30, 40, 50, 60, 80 and 100 kR) using Co60 gamma irradiation chamber at CCS Haryana Agricultural University, Hisar, (Haryana), India. Significant variations were recorded for all the seedling traits studied while major impact was noticed on the seedling after reaching the cotyledonary stage and doses above 40 kR showed absolute mortality of the seedlings. Based on probit analysis, the optimum LD50 dose lies in the range of 20-23 kR. Glycosidic profiling of 296 mutants using high-performance liquid chromatography showed decreased total steviol glycoside content with increased radiation dose. Doses 5 kR and 10 kR, were found to be effective in increasing the overall glycosidic content. A total of 72 promising mutants were also screened for increased rebaudioside-A stevioside ratio. Comparison of nuclear DNA content using flow cytometry revealed a similar decrease in the total nuclear DNA content with increase in dosage of gamma rays. The average genome size at 5, 10, 15, 20 and 30 kR treatments were 2.72, 2.69, 2.68, 2.70 and 2.66 pg as compared to 2.72 pg in control. Mild dose of gamma rays (5 and 10 kR) in stevia were found to be effective in improving the mean steviol glycoside content and may be used in future stevia mutation programmes. [ABSTRACT FROM AUTHOR]

Introduction: Osteosarcoma (OS) is a rare and aggressive form of bone cancer that primarily affects the long bones of the body, such as the arms and legs. It is characterized by the uncontrolled growth of malignant cells in the bone tissue, leading to the formation of abnormal and painful bone masses. Steviol glycosides have been widely used as natural noncalorie sweeteners and are the collective name of the sweet substances found naturally in the plant Stevia rebaudiana, which is commonly called Stevia. Our study aimed to analyze the anticancer activity of Stevioside in OS. Materials and Methods: Stevioside was applied to OS cells, and the levels of Bcl xL, Bcl-2, and Bax were then estimated. The results of three separate studies, each carried out in triplicate, were expressed as the mean ± standard errors of the mean (SEM). One-way ANOVA was used for statistical analysis. Results: The findings showed that the effect of Stevioside on sarcoma osteogenic cells with mean ± SEM as 0.74 ± 0.05, 0.69 ± 0.09, 0.46 ± 0.09 for Bcl-xL gene, 0.98 ± 0.06, 0.58 ± 0.07, 0.5 ± 0.07 for Bcl-2 gene, and 1.2 ± 0.08, 1.45 ± 0.11, 1.67 ± 0.12 for Bax gene, respectively, when treated with untreated control cells. Conclusion: The study concludes its action against bone OS cells was significant with apoptotic induction. Stevia has a wide range of health benefits as well as being a plant-based diet it has less of side effects and promoting features even by intaking it daily along with other medicines. [ABSTRACT FROM AUTHOR]

Understanding the edulcorant profile of synthetic glucosyl steviol glycosides (GSGs) and rare natural steviol glycosides (SGs) is challenging due to their numerous species and rareness. This study developed a computational model based on the interactions of SG molecules with human sweet and bitter taste receptors (hSTR/hBTR). The models demonstrated a high correlation between the cumulative interaction energies and the perceived sweetness of SGs (R2 = 0.97), elucidating the mechanism of the diverse sweetness of SGs. It also revealed that more (within three) glucose residues at the C-13 position of the SG molecule yield stronger sweetness and weaker bitterness. Furthermore, the computational prediction was consistently validated with the known sweetness of GSG and also aligned well with that of several natural mogrosides. Thus, this model possesses a potential to predict the sweetness of SGs, GSGs, and mogrosides, facilitating the application or targeted synthesis of GSGs with desired sensory profiles. [ABSTRACT FROM AUTHOR]

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Stevioside is a secondary metabolite of diterpenoid glycoside production in plants. It has been used as a natural sweetener in various foods because of its high sweetness and low-calorie content. In this study, we constructed a Saccharomyces cerevisiae strain for the complete synthesis of stevioside using a metabolic engineering strategy. Firstly, the synthesis pathway of steviol was modularly constructed in S. cerevisiae BY4742, and the precursor pathway was strengthened. The yield of steviol was used as an indicator to investigate the expression effect of different sources of diterpene synthases under different combinations, and the strains with further improved steviol yield were screened. Secondly, glycosyltransferases were heterologously expressed in this strain to produce stevioside, the sequence of glycosyltransferase expression was optimized, and the uridine diphosphate-glucose (UDP-Glc) supply was enhanced. Finally, the results showed that the strain SST-302III-ST2 produced 164.89 mg/L of stevioside in a shake flask experiment, and the yield of stevioside reached 1104.49 mg/L in an experiment employing a 10 L bioreactor with batch feeding, which was the highest yield reported. We constructed strains with a high production of stevioside, thus laying the foundation for the production of other classes of steviol glycosides and holding good prospects for application and promotion. [ABSTRACT FROM AUTHOR]

Steviol glycosides (SGs) are natural sweeteners derived from stevia leaves, which have various applications in food and beverage products. The extraction efficiency of SGs depends on several factors, such as solvent type, solid to solvent ratio, centrifugal force, and temperature. This study aimed to compare the effects of different solvents (ethanol and water) and leaf moisture (dry and fresh) on the extraction efficiency of major steviol glycosides (SGs) of rebaudioside A (Reb A), stevioside (ST), and rebaudioside C (Reb C) in stevia (var. Levent 93) plant. A Box–Behnken design was used to optimise the extraction parameters for each extraction type. The results showed that ethanol was a more effective solvent than water, however, aqueous extraction was more environmentally friendly and low-cost, and could also yield high concentrations of SGs when fresh leaves were used. The major SGs had similar concentrations in ethanolic extraction, but Reb A was twice as high as ST in aqueous extraction. Reb C was influenced by the solid to solvent ratio in both extraction types, but more so in water extraction. Temperature had a positive effect on ST and Reb C in water extraction of fresh leaves, but not in water extraction of dry leaves or ethanolic extraction. The results of this study contribute to the optimisation of SGs extraction from stevia leaves and provide insights for future research on the effects of different solvents and extraction parameters on the quality and purity of SGs. [ABSTRACT FROM AUTHOR]

Stevia plants are well-known for their ability to synthesize steviol glycosides (SGs), a natural sweetener blend. The principal SGs include stevioside (STV) and Rebaudioside-A (Reb-A), with the latter exhibiting superior sweetness and organoleptic properties. UDP glucosyltransferase-76G1 (UGT76G1) is responsible for converting STV to Reb-A, determining the intensity of sweetness. A better understanding of the structure/activity of SrUGT76G1 could provide insights into Reb-A production in stevia plants. To this end, a combination of enzymatic assays and sequencing analysis was performed using two stevia genotypes (Brazilian and Spanish) with contrasting Reb-A production capabilities (off/on). Relative expression of SrUGT76G1 gene showed remarkably higher expression (~ threefold) in Spanish samples compared to Brazilian ones. Foliar protein fractions (crude or partially purified extract) from Brazil plants were unable to convert STV into Reb-A under in vitro conditions, resulting in undetectable levels of Reb-A by HPLC. Molecular analyses revealed that the Brazilian SrUGT76G1 gene not only presents a premature stop codon, resulting in the absence of PSPG motif responsible for the binding of glycosyl groups, but also exhibits mutations affecting key amino acid residues in the acceptor-binding pocket. These alterations provide a plausible explanation for the Brazilian protein inability to catalyze the transformation of STV into Reb-A. [ABSTRACT FROM AUTHOR]

AbstractStevia rebaudiana is zero-calorie bio-sweetener and furnishes the best nutrition out of it. The study was conducted to characterize the extracts from water, ethanol, methanol, and supercritical fluid for Steviosides/SGs. The compounds found in appreciable quantities were Stevioside (665.34 ± 27.27 to 1107.95 ± 50.96 mg/kg), Rebaudioside A (383.38 ± 17.25 to 792.15 ± 38.02 mg/kg) and Steviol (357.26 ± 14.64 to 485.25 ± 22.32 mg/kg). Stevia cookies were prepared by replacing sucrose with Stevia powder (10%), water extract (1%), and supercritical extract (3%). Bio-efficacy rats modeling trials were done to check their impact against hyperglycemia and hypercholesterolemia. Blood glucose level was reduced from 4.54 to 7.00%, insulin level was increased by 4.27 to 6.13% due to diets enriched with stevia powder and extracts as compared to the control. In hypercholesterolemic rats, up surged cholesterol level was reported to reduce as a function of Stevia powder and extracts from 1.28 to 5.47%. Substantial increment in HDL, and reduction in LDL and triglycerides was recorded in Stevia leaves powder and extracts treatments by 2.79–6.66%, 2.68–4.16%, and 3.12–5.36, respectively. Stevia cookies administration in rats showed non-significant impact on the liver, renal, and hepatological parameters, while the safety of cookies was improved. Therefore, it can be concluded from the outcomes that in addition to sweetness, Stevia health health-beneficial effects make it suitable to be included in cookies.

This work is a part of the project for investigations of hydrodynamics and mass transfer in an adsorption apparatus with ion-exchange resins during the extraction of stevioside from stevia extract. Nowadays the issues of improving the structural-sorption characteristics while increasing selectivity to certain substances, expanding the range, simplifying the manufacturing technology and reducing the cost of production of industrial adsorbents are extremely relevant. The submitted work is devoted to mathematical modeling and a theoretical description of adsorption in the layer of expanded ion-exchange resins. By this, the main aspects of adsorption in a layer of porous material have been considered, and a model of the geometric structure of the adsorption layer has been developed. The original contribution of the work and its scientific novelty lie in the fact that a mathematical model of the evolution of a two-component dispersed phase has been developed and qualitatively analyzed taking into account competitive adsorption and the non-equilibrium nature of mass transfer between the adsorption surface of the porous material and the dispersed phase. The results and conclusions of the work are recommended to be used in planning and conducting research work in the field of intensification of heat and mass transfer processes and engineering design of adsorption chemical apparatuses and adsorption columns. [ABSTRACT FROM AUTHOR]

Background: Stevioside (SV) with minimal calories is widely used as a natural sweetener in beverages due to its high sweetness and safety. However, the effects of SV on glucose uptake and the pyruvate dehydrogenase kinase isoenzyme (PDK4) as an important protein in the regulation of glucose metabolism, remain largely unexplored. In this study, we used C2C12 skeletal muscle cells that was induced by palmitic acid (PA) to assess the effects and mechanisms of SV on glucose uptake and PDK4. Methods: The glucose uptake of C2C12 cells was determined by 2‐NBDG; expression of the Pdk4 gene was measured by quantitative real‐time PCR; and expression of the proteins PDK4, p‐AMPK, TBC1D1 and GLUT4 was assessed by Western blotting. Results: In PA‐induced C2C12 myotubes, SV could significantly promote cellular glucose uptake by decreasing PDK4 levels and increasing p‐AMPK and TBC1D1 levels. SV could promote the translocation of GLUT4 from the cytoplasm to the cell membrane in cells. Moreover, in Pdk4‐overexpressing C2C12 myotubes, SV decreased the level of PDK4 and increased the levels of p‐AMPK and TBC1D1. Conclusion: SV was found to ameliorate PA‐induced abnormal glucose uptake via the PDK4/AMPK/TBC1D1 pathway in C2C12 myotubes. Although these results warranted further investigation for validation, they may provide some evidence of SV as a safe natural sweetener for its use in sugar‐free beverages to prevent and control T2DM. [ABSTRACT FROM AUTHOR]

Human amoebiasis still represents a major health problem worldwide. Metronidazole has been used as the most common drug to treat the disease; however, it is also known that the drug causes undesirable side effects. This has led to the search for new pharmacological alternatives which include phytochemical compounds with antiamoebic effects. We analyzed the amoebicidal activity of stevioside (STV), a diterpene glycoside present in Stevia rebaudiana, on trophozoites of E. histolytica. Different concentrations of STV were tested, and an inhibitory concentration of 50% of cell viability (IC50) was determined with an exposition of 9.53 mM for 24 h. Trophozoites exposed to STV showed morphological changes evidenced by the decrease in the basic structures related to the movement and adherence to the substrate, as well as ultrastructural features characterized by a loss of regularity on the cell membrane, an increase in cytoplasmic granularity, and an increase in apparent autophagic vacuoles. Also, the decrease in cysteine protease expression and the proteolytic activity of trophozoites to degrade the cell monolayer were analyzed. A histological analysis of hamster livers inoculated with trophozoites and treated with STV showed changes related to the granulomatous reaction of the liver parenchymal tissue. Our results constitute the first report related to the possible use of STV as a therapeutic alternative in amoebiasis. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni is a plant native to South America that has gathered much interest in recent decades thanks to diterpene glycosides, called steviosides, which it produces. These compounds are characterised by their sweetness, which is 250–300 times higher than saccharose, and they contain almost no caloric value. Stevia is currently also grown outside the South American continent, in various countries characterised by warm weather. This research aimed to determine whether it is viable to grow Stevia rebaudiana plants in Poland, a country characterised by a cooler climate than the native regions for stevia plants. Additionally, the impact of adding various dosages and forms of nitrogen fertiliser was analysed. It was determined that Stevia rebaudiana grown in Poland is characterised by a rather low concentration of steviosides, although proper nitrogen fertilisation can improve various characteristics of the grown plants. The addition of 100 kg or 150 kg of nitrogen per hectare of the field in the form of urea or ammonium nitrate increased the yield of the stevia plants. The stevioside content can be increased by applying fertilisation using 100 kg or 150 kg of nitrogen per hectare in the form of ammonium sulfate. The total yield of the stevia plants grown in Poland was lower than the yield typically recorded in warmer countries, and the low concentration of steviosides in the plant suggests that more research about growing Stevia rebaudiana in Poland would be needed to develop profitable methods of stevia cultivation. [ABSTRACT FROM AUTHOR]

Steviosides extracted from the leaves of the plant Stevia rebaudiana are increasingly used in the food industry as natural low-calorie sweeteners. Phthalates in food are often assumed to arise from food containers or packaging materials. Here, experiments were carried out to identify the potential sources of DMP, DBP, DIBP, and DEHP in the leaves of stevioside through investigation of their content in native stevioside tissues, soils, and associated agronomic materials. The results show that phthalate contamination was present in all the samples tested, and the influence of regional factors at the provincial level on the content of plasticizers in stevia leaves was not significant. Phthalates in stevia leaves can be absorbed into the plant body through leaves and roots. Using resin removal, the phthalate content in stevioside glycosides was reduced to less than 0.05 ppm, and some indicators were far lower than the limit standard in EU food. [ABSTRACT FROM AUTHOR]

Sugar-free food has been gaining popularity because of low-calorie content. But sugar replacement by high-intensity sweeteners can negatively affect sensory. In this study, the effect of the addition of sucralose (Suc), stevioside (Ste), and erythritol (Ery) as sugar substitutes on the sensory profile and overall acceptance of ice cream were evaluated by penalty analysis (PA) based on the check-all-that apply (CATA) method, with those of the partial least squares (PLS) regression. Twelve sweetening agents of ice cream samples were presented to 106 consumers who answered on an overall liking question using the 15-point hedonic scale and a CATA question with 32 attributes that described the sensory characteristics of ice cream. The results showed that mixed sweeteners (60%Suc+20%Ste+20%Ery or 60%Suc+10%Ste+30%Ery) can present an advantageous performance when used separately, and making ice cream similar to that of sucrose (Sac) added. Adding Suc, Ste, and Ery to ice cream hardly felt bitterness, astringency, and chemical-like sensations of the sweetening agent. The significant difference between different sweeteners is the intensity and speed of sweetness. Developing combination of high-potency sweeteners that can make sweetness appear quickly could open up new ways to design sugar-free ice cream. [ABSTRACT FROM AUTHOR]

Stevioside is an important natural sweetener in food and beverages. There are concerns about its safety, but few methods for its determination. Silver nanoparticles (Ag NPs) functionalized with 4-mercaptophenylboronic acid (4-MPBA) were successfully used to determine stevioside in beverages based upon surface-enhanced Raman spectroscopy (SERS). The Ag NPs self-assemble with 4-MPBA through the covalent interaction of their sulfhydryl groups with the metal particles. Boronic acid groups bonded to 1,2-/1,3-diol groups form cyclic boronic esters with strong affinity and significant specificity for stevioside. The combination of the two leads to an alteration of the 4-MPBA vibrational mode. The change in the orientation of the moiety and the charge transfer resulted in a significant increase of the SERS signal. The substrates showed strong specificity and sensitivity to stevioside in the presence of other sweeteners. Also, the substrate modification conditions were optimized, including the time, ratio, and concentration. The limit of detection (LOD) for stevioside in beverages was 0.210 μmol/L, and the recovery was from 98.4% to 109.4%. In summary, the presented SERS method provides high sensitivity for stevioside. [ABSTRACT FROM AUTHOR]

Lighting conditions are an important controller of plant growth and development, and they affect secondary metabolite synthesis. In this research, we explored the effect of additional UV irradiation of various ranges in addition to the main one at PPFD 160 µmol m−2 s−1 on the accumulation of some secondary metabolites of stevia (Stevia rebaudiana Bertoni). The fresh weight of leaves was slightly higher under additional UV-A and UV-B irradiation compared with the control variant, and the leaf surface area was significantly larger, respectively, by 23.3 and 20.7% than in the control variant, while the rate of photosynthesis did not decrease. Plants under additional UV-B and UV-C irradiation were under the greatest light stress, as evidenced by a decrease in antioxidant capacity by an average of 30% compared to the control and UV-A. The total flavonoid content was significantly higher (by 74%) under UV-B irradiation. The highest concentration of steviol glycoside was observed during budding and flowering under UV-B and UV-C irradiation (by 13.2 and 11.3%, respectively). Analysis of hyperspectral images, chlorophyll fluorescence, and vegetation indices showed light stress increasing under UV-C irradiation, which caused an increase in the relative chlorophyll content, scorches, leaf morphology changes, a CO2 absorption rate decrease, and plant growth inhibition. UV-B irradiation can be used as an optimal type of irradiation based on a set of indicators. [ABSTRACT FROM AUTHOR]

Introduction and Background: Diabetes is a chronic metabolic disease characterized by elevated blood glucose levels and is one of the main global health concerns. Synthetic sugar substrate has many side effects such as leukemia, bladder cancer, hepatotoxicity, breast cancer, headache, and brain toxicity. The WHO and FDA has recently banned some of the synthetic sugar alternatives due to their carcinogenic effects.Objective and Methodology: Therefore, the main objective of the current study was to investigate the safety and binding affinity of Stevioside with Glucose Transpoter-4 (GLUT-4), Akt, Insulin Receptor (IR) and Insulin Receptor Substrate-1 (IRS-1) to confirmed that Stevioside is one the potent natural sweetener/drug for diabetes. This study delves into the molecular interaction between Stevioside and key diabetic proteins: GLUT-4, Akt, IR and IRS-1. A precise molecular docking approach was used to simulate the binding affinity of Stevioside to these proteins. The pharmacokinetic properties of the molecule should be taken into consideration as important variables throughout the virtual screening process.Results: The result of active site analysis of GLUT-4, Akt, IR and IRS-1 showed a zone of 2158.359 Ǻ2, 579.259 Ǻ2, 762.651 Ǻ2, and 152.167 Ǻ2 and a volume of 2765.094 Ǻ³, 355.567 Ǻ³, 686.806 Ǻ³, and 116.874 Ǻ³, respectively. Docking analysis of the Stevioside compound showed the highest docking energy with scores of −9.9 with GLUT-4, −6.7 with Akt, −8.0 with IR and −8.8 with IRS-1. Studies indicated that it remains undigested by stomach acids and enzymes and is not absorbed in the upper small intestine. Further, tests revealed no hepatotoxicity, AMES toxicity, or skin sensitivity, making it a promising candidate for safe consumption as drug metabolism.Conclusion and Recommendations: Instead of other sugar alternatives, Stevioside will help diabetic patients with a lower chance of infections, lowered blood pressure/blood sugar, and increased glucose uptake in diabetic muscles. Stevioside is a natural sweetener, and the current study recommends its usage in various dietary products for diabetic patients.

Abstract Recent studies indicate a significant upregulation of gasdermin D (GSDMD) in acute kidney injury (AKI), a severe medical condition characterized by high morbidity and mortality globally. In this study, we identified and validated the therapeutic effects of small molecule inhibitors targeting the GSDMD pathway for AKI treatment. Using a drug screening assay, we evaluated thousands of small molecules from DrugBank against Lipopolysaccharide (LPS) and Nigericin‐stimulated immortalized bone marrow‐derived macrophages (iBMDMs) to discern GSDMD pathway activators. We simulated AKI in primary renal tubular epithelial cells using hydrogen peroxide (H2O2) exposure. Furthermore, AKI in mouse models was induced via cisplatin and ischemia/reperfusion. Our findings highlight stevioside as a potent GSDMD activator exhibiting minimal toxicity. Experimental results, both in vitro and in vivo, demonstrate stevioside's significant potential in alleviating renal tubular epithelial cell injury and AKI histological damage. After stevioside treatment, a notable decrease in cleaved GSDMD‐N terminal levels was observed coupled with diminished inflammatory factor release. This observation was consistent in both cisplatin‐ and ischemia/reperfusion‐induced AKI mouse models. Collectively, our research suggests that stevioside could be a promising candidate for modulating GSDMD signaling in AKI treatment.

The rise in popularity of non-caloric sweeteners (NCS) among obese and diabetic patients is due to their ability to provide a sweet taste without any caloric input. However, NCS consumption may be linked to metabolic disorders. The mechanisms behind these adverse effects are still unclear, which suggests that NCS may alter the metabolic activity of the gut microbiome, leading to enteric environmental perturbation and resulting in physiological anomalies in the host. This study investigates how Escherichia coli, a common gut microbe, reacts to three NCS, two of which come from nature (glycyrrhizin and stevioside) and one that is made artificially (sucralose). To assess the impact of these NCS, this study investigated the growth, gene expression, and metabolic pathways of E. coli under different sweetener loads. Compared to the untreated control, low amounts of glycyrrhizin made E. coli grow faster, while similar amounts of sucralose and stevioside had no or a less noticeable effect. At higher concentrations, these sweeteners slowed down or inhibited the growth of the bacteria. Thus, NCS may have dose-dependent impacts on gut microbes. After treatment with amounts that corresponded to the acceptable daily intake, the expression of key metabolic genes showed altered expression, which may potentially affect their metabolism. At different concentrations of the NCS, there were clear differences in the global metabolomic profile between the control and the different NCS treatments. Under in vitro conditions, glycyrrhizin and sucralose appeared to have a less divergent impact on E. coli growth, gene expression, and metabolism, which may suggest that these are relatively safer sugar substitutes for humans. [ J Adv Biotechnol Exp Ther 2023; 6(3.000): 659-672]

Stevia rebaudiana (Bertoni) is a highly valuable crop for the steviol glycoside content in its leaves, which are no-calorie sweeteners hundreds of times more potent than sucrose. The presence of health-promoting phenolic compounds, particularly flavonoids, in the leaf of S. rebaudiana adds further nutritional value to this crop. Although all these secondary metabolites are highly desirable in S. rebaudiana leaves, the genes regulating the biosynthesis of phenolic compounds and the shared gene network between the regulation of biosynthesis of steviol glycosides and phenolic compounds still need to be investigated in this species. To identify putative candidate genes involved in the synergistic regulation of steviol glycosides and phenolic compounds, four genotypes with different contents of these compounds were selected for a pairwise comparison RNA-seq analysis, yielding 1136 differentially expressed genes. Genes that highly correlate with both steviol glycosides and phenolic compound accumulation in the four genotypes of S. rebaudiana were identified using the weighted gene co-expression network analysis. The presence of UDP-glycosyltransferases 76G1, 76H1, 85C1, and 91A1, and several genes associated with the phenylpropanoid pathway, including peroxidase, caffeoyl-CoA O-methyltransferase, and malonyl-coenzyme A:anthocyanin 3-O-glucoside-6″-O-malonyltransferase, along with 21 transcription factors like SCL3, WRK11, and MYB111, implied an extensive and synergistic regulatory network involved in enhancing the production of such compounds in S. rebaudiana leaves. In conclusion, this work identified a variety of putative candidate genes involved in the biosynthesis and regulation of particular steviol glycosides and phenolic compounds that will be useful in gene editing strategies for increasing and steering the production of such compounds in S. rebaudiana as well as in other species. [ABSTRACT FROM AUTHOR]

Starting from isosteviol, a series of diterpenoid 1,3-aminoalcohol derivatives were prepared via stereoselective transformations. The acid-catalysed hydrolysis and rearrangement of natural stevioside produced isosteviol, which was transformed into the key intermediate methyl ester. In the next step, an 1,3-aminoalcohol library was prepared by the reductive amination of the intermediate 3-hydroxyaldehyde obtained from isosteviol in a two-step synthesis. To study the effect of the carboxylate ester function at position 4, the free carboxylic acid, benzyl ester and acryloyl ester analogues were prepared as elongated derivatives in comparison with our earlier results in this field. The antiproliferative activity of compounds against human tumour cell lines (A2780, HeLa, MCF-7 and MDA-MB-231) was investigated. In our preliminary study, the 1,3-aminoalcohol function with N-benzyl or (1H-imidazol-1-yl)-propyl substitution and benzyl ester moiety seemed essential for the reliable antiproliferative activity. The results obtained could be a good starting point to further functionalisation towards more efficient antiproliferative diterpenes. [ABSTRACT FROM AUTHOR]

Ethephon, as an ethylene-releasing compound, is frequently used for the regulation of plant growth and metabolism. The present study aimed to investigate the impact of ethephon application at various concentrations (0, 0.37, 0.75, 1.5, and 3 mM) and stages [(treatment on seed, and foliar application on seedling (6-leaf stage) and full-grown plant)] on growth and metabolites biosynthesis of stevia (Stevia rebaudiana L.). It was observed that ethephon had no significant effects on seed germination, while seed treated by 0.37 mM ethephon produced stevia plants with significant leaf biomass. The foliar application of ethephon on full-grown plants caused a significant loss in leaf production compared to non-ethephon-treated plants (control). The most significant increase (39% compared to control) in leaves dry weight was recorded at 0.75 mM ethephon applied on the seedling stage. A significant increase in steviol glycosides (SVglys) content was observed when 0.37 and 0.75 mM ethephon were applied to stevia seeds and seedlings, respectively. This result was equally certain regarding Rebaudioside (Reb) A and Stevioside (Stev). The SVglys production in stevia was significantly increased (50%, compared to control) when ethephon was applied to seeds and seedlings at 0.75 mM concentration. However, ethephon foliar application on full-grown plants sharply decreased the SVglys biosynthesis. The ethephon concentrations of 0.37 and 0.75 considerably increased the sucrose, glucose, and fructose content of the leaves. Based on the results presented, it can be concluded that stevia response to exogenous ethephon depends on ethephon concentration and time of application. In this respect, the application of 0.75 mM ethephon on seeds and seedlings could be an appropriate strategy for biosynthesis and accumulation of metabolites in stevia. [ABSTRACT FROM AUTHOR]

Steviol and isosteviol were prepared from the commercially available sweetener stevioside and converted into lipophilic F16 hybrids. Their cytotoxicity was determined in SRB assays and showed to depend on both the substitution pattern of the aromatic substituent as well as on the spacer length. Therefore, compound 25 held an IC50 (A2780) of 180 nM, thus surpassing the activity of comparable rhodamine hybrids. Several of the compounds were also able to overcome drug resistance in the A2780/A2780cis model. Extra staining experiments showed a similar subcellular accumulation pattern of the F16 hybrids as a well-established mitocan, hence proving preferential mitochondrial accumulation but also some other accumulation in other cellular areas. [ABSTRACT FROM AUTHOR]

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Stevia rebaudiana is rich in glycosides and polyphenolic bioactive substances, which have the function of antibacterial, antioxidant and lowering blood glucose and lipids. With the rapid development of animal husbandry, Stevia rebaudiana and its extracts have been widely used in livestock and poultry production. In the process of stevioside production and processing, a large number of by-products, stevia residues, are produced. Stevia residues have the potential to be used as unconventional feed raw materials. In the paper, the application progress of active substances and by-products of Stevia rebaudiana in livestock and poultry production is summarized, which can provide a reference for the research and application of Stevia rebaudiana as a functional feed additive in livestock production. [ABSTRACT FROM AUTHOR]

A series of novel diterpene-type 1,3-aminoalcohols and their regioisomers have been synthesised from natural stevioside in a stereoselective manner. The key intermediate β-keto alcohol was prepared using Wagner–Meerwein rearrangement of the epoxide derived from steviol methyl ester. The primary aminoalcohol was formed via Raney-nickel-catalysed hydrogenation of an oxime, and a versatile library of aminoalcohols was synthesised using a Schiff base with the primary amines. The aminoalcohol regioisomers were prepared from the mesylate of the β-keto alcohols. The corresponding primary aminoalcohol was formed via the palladium-catalysed hydrogenation of hydroxyl-azide, and click reactions of the latter were also carried out. The new compounds were characterised using 1D- and 2D-NMR techniques and HRMS measurements. The in vitro investigations showed high inhibition of cell growth in human cancer cell lines (HeLa, SiHa, A2780, MCF-7 and MDA-MB-231) in the case of naphthalic N-substituted derivatives. The antiproliferative effects were assayed using the MTT method. [ABSTRACT FROM AUTHOR]

Elderberry and vine tea, renowned for their wealth of bioactive constituents and potent antioxidant prowess, hold remarkable promise within a wide array of culinary contexts. This study presents a pioneering advancement in the realm of compound effervescent tablet formulation. Employing the response surface design optimization, this work develops a formulation comprising a total disintegrant (acid-to-base ratio 1.3 : 1) at 50%, elderberry extracts at 31.7%, ultra-micro vine tea powder at 8.3%, stevioside at 3.4%, PEG-6000 at 2.7%, mannitol at 2.9%, and PVP at 1%. Under these carefully optimized conditions, the resultant tablet exhibits remarkable attributes including an average disintegration time of 184.50 ± 4.65 s , foaming quantity of 30.64 ± 2.10 mg / g , and tablet hardness measuring 54.59 ± 3.41 N , with a weight uniformity well within the ±5%. Regarding the antioxidant efficacy, the total flavonoid content attains 76.79 ± 3.76 mg RE/g, and phenolic content reaches 94.84 ± 4.95 mg GAE / g. Moreover, the E C 50 values for scavenging 1,1-diphenyl-2-picrohydrazine (DPPH), hydroxyl (OH), and 2, 2 ′ -azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) radicals are determined at 0.4667 mg/mL, 0.9772 mg/mL, and 0.5014 mg/mL, respectively. This investigation underscores the performance of the effervescent tablet in satisfying stringent physicochemical standards, while also showcasing outstanding antioxidant potency, paving the way for the advancement of antioxidant-functional foods and sustainable exploitation of natural resources. [ABSTRACT FROM AUTHOR]

Objective: An excessive buildup of adipose tissue is a defining feature of overnutrition, and a significant fraction of the world's population suffers from obesity. Overnutrition is associated with the deterioration of mitochondrial functions in the brain in the case of obesity. In this study, we evaluated the effects of stevioside (ST) which is a calorie-free, naturally occurring herbal sweetener made from Stevia rebaudiana (Bertoni) on the oxidant-antioxidant balance in the brain in cases of overnutrition. Accordingly, the effects of ST consumption on the oxidant-antioxidant balance in the brain was evaluated and determined in a case study of overfeeding adult zebrafish for 15 days. Materials and Methods: Zebrafish were placed in four groups; the control group (C); overfed group (OF); low-dose (1mg/L) ST treated OF group (OF+LDS); and the high-dose ST (5mg/L) treated OF group (OF+HDS). The levels of lipid peroxidation (LPO) were evaluated together with nitric oxide (NO) to determine the oxidant status. The antioxidant status from the activities of the superoxide dismutase (SOD) and glutathione S-transferase (GST) were determined in brain tissues. Results: The ST treatment decreased the increased LPO and NO levels in overfed zebrafish and increased SOD and GST activities in a dose-dependent manner. Conclusion: ST exerted an antioxidant effect on the possible damage mechanisms that could occur in the brain in case of overnutrition by decreasing oxidative stress and improving the antioxidant enzyme activities. [ABSTRACT FROM AUTHOR]

[Objectives] To optimize the extraction and preparation technology of Wuwei Xiaoke granules. [Methods] Taking the extraction rate of extract as the scoring standard, the water extraction technology was optimized by orthogonal test. The influence of the proportion of phar- maceutical excipients on the molding conditions of Wuwei Xiaoke granules was investigated using granule molding rate, solubility, moisture, granularity, water-soluble extract and microorganism examination as evaluation indicators, and the optimal molding technology was optimized. [Results] The extraction technology was soaking in water for 0.5 h and heat extraction twice for 1 h each time; adding 10 times the amount of water in the first time, and adding 8 times the amount of water in the second time. The best molding technology was: extract density 1.13-1.16 (55-60 °C), extract: soluble starch = 1:2, and 0.15% stevioside. [Conclusions] The water extraction technology and granule molding technology optimized by orthogonal test are reliable and stable, with good granular characteristics, easy oral administration and good solubility, which can maximize the comprehensive quality of Wuwei Xiaoke granules, and provide an effective reference for the preparation and production of Wuwei Xiaoke granules. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to systematically review the functionalities, safety regulations and product applications of herb Stevia rebaudiana extract. This plant material is embedded with multiple functionalities such as antioxidant, antidiabetics, anti-inflammation and antimicrobial. The regulations released from global authorities are covered to ensure the safety premise of stevia. Besides, the product applications of the extract of aerial parts of the herb S. rebaudiana helps us to recognize its value from commercial side. Design/methodology/approach: Relevant literatures are selected and obtained from main scientific databases such as Google Scholar, Web of Science, PubMed and trade magazines published between 2000 and 2023. The keywords and their possible combinations such as sweetening, antioxidant, antidiabetics, anti-inflammation, safety and product development were used to ensure the preciseness and completeness of literature searching. Major data such as sweetness, total phenolic content and dose together with latter critical conclusions from searched publications were appropriately used and discussed. In this review, approximately 150 scientific literatures were meticulously ordered and analyzed. In applications, it is the first time that sentiment analysis was used to obtain a market assessment of the stevia-containing products. Findings: This review paper helps rearrange the scientific affairs of those stevia extract's functions like sweetening, antioxidant, antidiabetics and inflammation. Sweetness indexes of steviol glycosides were summarized together for comparison while various in vitro and 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 and Joint FAO/World Health Organization Expert Committee to ensure the safety endorsement before commercialization. Then, this study discussed about the market performance of stevia ingredients or products with the self-developed data analytics. This study also 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 consumers. Originality/value: This review paper precisely presents the evidential information about the stevia's multiple functionalities with mechanisms and global regulation milestones. To the best of the authors' knowledge, it is then the first time to probe the stevia-containing products' market performance through data analytics. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Stevioside (SV) with minimal calories is widely used as a natural sweetener in beverages due to its high sweetness and safety. However, the effects of SV on glucose uptake and the pyruvate dehydrogenase kinase isoenzyme (PDK4) as an important protein in the regulation of glucose metabolism, remain largely unexplored. In this study, we used C2C12 skeletal muscle cells that was induced by palmitic acid (PA) to assess the effects and mechanisms of SV on glucose uptake and PDK4. Methods The glucose uptake of C2C12 cells was determined by 2‐NBDG; expression of the Pdk4 gene was measured by quantitative real‐time PCR; and expression of the proteins PDK4, p‐AMPK, TBC1D1 and GLUT4 was assessed by Western blotting. Results In PA‐induced C2C12 myotubes, SV could significantly promote cellular glucose uptake by decreasing PDK4 levels and increasing p‐AMPK and TBC1D1 levels. SV could promote the translocation of GLUT4 from the cytoplasm to the cell membrane in cells. Moreover, in Pdk4‐overexpressing C2C12 myotubes, SV decreased the level of PDK4 and increased the levels of p‐AMPK and TBC1D1. Conclusion SV was found to ameliorate PA‐induced abnormal glucose uptake via the PDK4/AMPK/TBC1D1 pathway in C2C12 myotubes. Although these results warranted further investigation for validation, they may provide some evidence of SV as a safe natural sweetener for its use in sugar‐free beverages to prevent and control T2DM.

Sweeteners are food additives consumed worldwide, especially by individuals with restrictive diets. This study evaluated the cytotoxic and genotoxic effects of sweeteners widely sold in Brazil through a bioassay with Allium cepa. Onion bulbs were exposed to different concentrations of sweeteners, and their root cells were stained with acetic carmine and analyzed under an optical microscope. Distilled water was used as a negative control, and glyphosate as a positive control. The results demonstrated that the mitotic index (MI) and the chromosome aberration index (CAI) of the three sweeteners tested did not differ significantly from the negative control, indicating that they are not toxic or mutagenic additives. This result is positive for consumers of these products, especially those who need to replace sugar due to dietary restrictions. However, they should be consumed with caution.

Due to the need of stevia plants to moderate temperature throughout the year and the high costs of its production inside greenhouses, therefore the Intercropping may be the optimum solved to get up heating in winter and shading in summer in addition to increasing the cropping area. The cultivation of these economic crops is needed to fill the nutritional gap of grains and oils. Field experiment was conducted through 2019/2020 and was replicated at 2020/2021 in the Experimental Farm of Mallawi Agricultural Research Station, El-Minia Governorate, Egypt to investigate the effect of some Intercropping patterns and fertilizers combination on the yield and quality of stevia as a natural sweetener. Randomized complete blocks design in split-plot arrangement was used where, the main plots consisted of five Intercropping patterns, while the fertilizers combinations were assigned in sub plot. Results showed that Intercropping pattern had a significant effect on most aspects of growth in both seasons. It was noticed that the treatment of 80% N mixed with Biofertilizers, and compost surpassed the other treatments in both seasons. The net profit of using mixing biofertilizer + Compost plus 80 % mineral N fertilizer for stevia and wheat intercrop recorded 651.075 &691.403 L.E. fed in the1st and 2nd successive seasons, respectively.

Polyphenols from stevia leaves (PPSs) are abundant byproducts from steviol glycoside production, which have been often studied as raw extracts from stevia extracts for their bioactivities. Herein, the PPSs rich in isochlorogenic acids were studied for their antimicrobial and anti-inflammatory properties, as well as their inhibitory effects on digestive enzymes. The PPSs presented stronger antibacterial activity against E. coli, S. aureus, P. aeruginosa, and B. subtilis than their antifungal activity against M. furfur and A. niger. Meanwhile, the PPSs inhibited four cancer cells by more than 60% based on their viability, in a dose-dependent manner. The PPSs presented similar IC50 values on the inhibition of digestive enzyme activities compared to epigallocatechin gallate (EGCG), but had weaker anti-inflammatory activity. Therefore, PPSs could be a potential natural alternative to antimicrobial agents. This is the first report on the bioactivity of polyphenols from stevia rebaudiana (Bertoni) leaves excluding flavonoids, and will be of benefit for understanding the role of PPSs and their application. [ABSTRACT FROM AUTHOR]

The aim of this study was to validate a method for determining nine types of steviol glycoside and its derivatives in food and beverage products, using ultrahigh-performance liquid chromatography tandem mass spectrometry with electrospray ionization (UHPLC ESI MS/MS). The performance characteristics of the analysis method were determined along with their suitability for the intended use. Coefficient of determination (R2) calibration curves from 0.2 to 1.0 mg L−1 were in the ranges of 0.9911–0.9990, 0.9939–1.0000 and 0.9973–0.9999 for a beverage, yogurt and snack, respectively. Intra-day precisions in terms of percent relative standard deviation (% RSD) of concentration, at 0.2, 0.5 and 1.0 mg L−1, for the beverage, yogurt and snack were lower than 15% (1.1–9.3%). At all concentrations, percentage recoveries were in the accepted range of 70–120%. For the matrix effect study, matrix-matched calibration was used for all compounds, obtaining a linear concentration range from 0.2 mg L−1 to 1.0 mg L−1. Almost all matrix-matched results presented as percentage recoveries were within the accepted range of 80–120%. The limit of detection (LOD) for steviol glycosides ranged from 0.003 to 0.078 μg g−1, while the limit of quantitation (LOQ) ranged from 0.011 to 0.261 μg g−1. These results indicate that the modified test method can be applied to determine the presence of steviol glycoside and its derivatives in a wide range of sample matrices. [ABSTRACT FROM AUTHOR]

The use of nanomaterials in biotechnology for the in vitro propagation of medical plants and the accumulation of certain biologically active metabolites is becoming an efficient strategy. This study aimed to evaluate the influence of the concentration (0, 1, 10, 50, and 100 mg L−1) of two types of nanofibers on the growth characteristics, the antioxidant status, and the production of steviol glycosides in micropropagated Stevia rebaudiana Bert. plantlets. The nanofibers were synthesized by aspartic acid derivatives (L-Asp) Ag salts self-organized into nanofibers with two different molecular structures: monomeric, containing one residue of L-Asp with one hydrophilic head which bonds one Ag ion (NF1-Ag salt); and dimeric, containing two residues of L-Asp with two hydrophilic heads which bond two Ag ions (NF2-Ag salt). An increase in the shoots from the explants' number and length, biomass accumulation, and micropropagation rate was achieved in the plants treated with the NF1-Ag salt in concentrations from 1 to 50 mg L−1 after 30 days of in vitro proliferation compared to the NF2-Ag salt. In contrast, the plants grown on MS media supplemented with NF2-Ag salt exhibited an increase in the level of stevioside, rebaudioside A, and mono- (CQA) and dicaffeoylquinic (DCQA) acids as compared to the NF1-Ag salt. [ABSTRACT FROM AUTHOR]

Alternative sweeteners, such as steviol glucosides from the plant Stevia rebaudiana Bertoni, are becoming increasingly popular for the design of next-generation foodstuffs. However, the bitter aftertaste of native steviol glucosides is one of the main reasons behind consumer reluctance towards stevia-containing products. Biocatalysis could be a sustainable solution to this problem, through addition of glucosyl moieties to the molecule. Glycoside hydrolases are enzymes performing transglycosylation reactions, and they can be exploited for such modifications. In the present work, the commercial β-glucanase Finizym 250L® was employed for the transglycosylation of stevioside. After optimization of several reaction parameters, the maximal reaction yield obtained was 19%, with barley β-glucan as the glycosyl donor. With the aim to develop a sustainable process, β-glucan extracts from different fungal sources were prepared. Pulsed Electric Field pretreatment of mycelial biomass resulted in extracts with higher β-glucan content. The extracts were tested as alternative glucosyl donors, reaching up to 15.5% conversion yield, from Pleurotus-extracted β-glucan. Overall, in the present work a novel enzymatic process for the modification of stevioside is proposed, with concomitant valorization of β-glucans extracted from fungal biomass, potentially generated as a byproduct from other applications, in concert with the principles of circular economy. [ABSTRACT FROM AUTHOR]

In the pharmacokinetic analysis of ethanol after oral administration, only single- or two-compartment models are used, but their precision in estimating pharmacokinetic parameters might be insufficient. In a recent study, pharmacokinetic analysis using a modified Norberg three-compartment model was performed after oral administration of differently sweetened alcoholic solutions and compared to pharmacokinetic analysis using the classic Widmark model. On three occasions, eight male volunteers consumed differently sweetened alcoholic solutions: non-sweetened, sweetened with sucrose, and sweetened with steviol glycoside. Blood ethanol concentration was determined from samples obtained at t = 15, 30, 60, 90, 120, 180 min after consumption. Pharmacokinetic analysis was performed model independently, using the classic Widmarks model and using the modified Norberg model. Results showed that estimated pharmacokinetic parameters depend on the type of model used. The classic Widmark model in particular overestimated the fraction of absorbed ethanol from the gastrointestinal system to systemic circulation. Furthermore, the type of sweetener also affected pharmacokinetic parameters, although the difference was not statistically significant. In conclusion, the novel pharmacokinetic model, while being more physiological, fits experimental data better and hence is more suitable for modelling real-life alcohol consumption. In addition, the effect of natural non-caloric sweetener steviol glycoside on ethanol pharmacokinetics, analysed for the first time in the current research, might be different when compared to the common-used sweetener sucrose. [ABSTRACT FROM AUTHOR]

Microfiltration and ultrafiltration are used for the purification process of stevia extract to retain steviosides and remove tannins. The main objective of this study was to obtain the operating conditions for the purification process of stevia extract that resulted in the lowest stevioside rejection and highest tannin rejection. The purification process of stevia extract using microfiltration membrane was carried out at transmembrane pressure (1.20, 1.40, 1.65, 1.80, and 1.90 bar), cross flow velocity (0.04, 0.06, and 0.11 m s-1), and stevioside concentration of feed (7.12, 10.25, 14.03, and 18.47 g L-1). The stevia extract purification process used ultrafiltration membrane at transmembrane pressure (1.20, 1.40, 1.65, 1.80, and 1.90 bar), cross flow velocity (0.06, 0.09, and 0.12 m s-1), and stevioside concentration of feed (4.59 and 10.36 g L-1). The first step purification process was carried out using a microfiltration membrane and the resulting permeate was used as feed for the ultrafiltration process. The second step purification process was carried out using an ultrafiltration membrane. The best operating conditions of the microfiltration process were feed stevioside concentration of 14.03 g L-1 at a transmembrane pressure of 1.90 bar and a cross flow velocity of 0.11 m s-1 with a permeate flux of 82.90 L m-2 h-1. The best operating conditions of the ultrafiltration process used a feed stevioside concentration of 10.36 g L-1 with a permeate flux of 26.51 L m-2 h-1 at a transmembrane pressure of 1.90 bar and a cross flow velocity of 0.12 m s-1. The microfiltration and ultrafiltration processes resulted in total stevioside rejection of 59.52 % and total tannin rejection of 57.99 %.

Stevioside is a secondary metabolite of diterpenoid glycoside production in plants. It has been used as a natural sweetener in various foods because of its high sweetness and low-calorie content. In this study, we constructed a Saccharomyces cerevisiae strain for the complete synthesis of stevioside using a metabolic engineering strategy. Firstly, the synthesis pathway of steviol was modularly constructed in S. cerevisiae BY4742, and the precursor pathway was strengthened. The yield of steviol was used as an indicator to investigate the expression effect of different sources of diterpene synthases under different combinations, and the strains with further improved steviol yield were screened. Secondly, glycosyltransferases were heterologously expressed in this strain to produce stevioside, the sequence of glycosyltransferase expression was optimized, and the uridine diphosphate-glucose (UDP-Glc) supply was enhanced. Finally, the results showed that the strain SST-302III-ST2 produced 164.89 mg/L of stevioside in a shake flask experiment, and the yield of stevioside reached 1104.49 mg/L in an experiment employing a 10 L bioreactor with batch feeding, which was the highest yield reported. We constructed strains with a high production of stevioside, thus laying the foundation for the production of other classes of steviol glycosides and holding good prospects for application and promotion.

Human amoebiasis still represents a major health problem worldwide. Metronidazole has been used as the most common drug to treat the disease; however, it is also known that the drug causes undesirable side effects. This has led to the search for new pharmacological alternatives which include phytochemical compounds with antiamoebic effects. We analyzed the amoebicidal activity of stevioside (STV), a diterpene glycoside present in Stevia rebaudiana, on trophozoites of E. histolytica. Different concentrations of STV were tested, and an inhibitory concentration of 50% of cell viability (IC50) was determined with an exposition of 9.53 mM for 24 h. Trophozoites exposed to STV showed morphological changes evidenced by the decrease in the basic structures related to the movement and adherence to the substrate, as well as ultrastructural features characterized by a loss of regularity on the cell membrane, an increase in cytoplasmic granularity, and an increase in apparent autophagic vacuoles. Also, the decrease in cysteine protease expression and the proteolytic activity of trophozoites to degrade the cell monolayer were analyzed. A histological analysis of hamster livers inoculated with trophozoites and treated with STV showed changes related to the granulomatous reaction of the liver parenchymal tissue. Our results constitute the first report related to the possible use of STV as a therapeutic alternative in amoebiasis.