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Conjugates of the diterpenoid isosteviol with uracil and 6-methyluracil (nucleoterpenoids) were synthesized and showed moderate in vitro cytotoxicity (IC50 values in the range 11.6–51.0 μM) against M-HeLa, HuTu 80, and MCF-7 human cancer cells. [ABSTRACT FROM AUTHOR]

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]

• Elicitors applied to Stevia activated enzymes and increased SGs. • SA was found to be the most effective treatment for increasing Reb A. • Elicitation impacted Stevia growth under SS, especially with Spd and SA combination. • The combination of MeJ + Spd was more effective in increasing stevioside content. Stevia rebaudiana Bertoni is a plant species with sweet-tasting leaves that can be used as a natural, low-calorie sweetener with potential health benefits. Salt stress can reduce plant growth and productivity, but the application of growth regulators like salicylic acid (SA), methyl jasmonate (MeJ), and spermidine (Spd) can manage various plant abiotic stresses and improve plant growth and productivity. In this work, we investigated the role of exogenous SA, MeJ, and Spd in conferring salt stress tolerance in Stevia by analyzing plant growth, chlorophyll (Chl), total phenolic, total carotenoid content, antioxidant defense system and steviol glycosides. The aim of a recent study was to assess the effects of these regulators on Stevia plants under both individual and combined salt stress conditions. Foliar application of these regulators improved plant growth under salt stress, with moderate salinity stress increasing glycoside compounds. SA was most effective in increasing rebaudioside A (Reb A), while MeJ + Spd combination was best for increasing stevioside (Stv) content. Individual applications of Spd, MeJ, and SA significantly impacted plant growth and antioxidant content, although their combined use was less effective. Spd application under salt stress yielded the highest increases in total carotenoid and Chl a content, while MeJ and Spd together significantly boosted Chl b content. The study found that SA enhanced superoxide dismutase (SOD) activity and reduced catalase (CAT) activity under salt stress, whereas MeJ alone increased both CAT and SOD activity. The distinct responses to Spd, SA, and MeJ suggest varied mechanisms in oxidative stress-induced antioxidant production. Overall, the use of these growth regulators can improve the growth, yield, and nutritional value of Stevia under salt stress, offering significant implications for agriculture and food security. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana boasts a wide range of medical and food applications and contains polysaccharides that exert beneficial effects against oxidative stress. In this study, we optimised the extraction of a polysaccharide (SRRP) from S. rebaudiana roots by employing a Box–Behnken design and response surface methodology. The optimal extraction conditions were as follows: 93.57 min, 71.67 °C, and a water-to-raw material ratio of 21.40 mL/g. Under these conditions, 14.00 ± 0.35% of crude polysaccharide was obtained. Treatment of RAW264.7 cells with SRRP prior to the addition of H2O2, a major contributor to oxidative damage, significantly increased cell viability. In addition, SRRP increased the levels of superoxide dismutase, catalase, and glutathione and reduced the levels of malondialdehyde in RAW264.7 cells. Therefore, SRRP can provide effective protection against H2O2-induced oxidative damage. These findings indicate the potential of SRRP as a natural antioxidant in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The quest for healthier beverage options has led to the development of low-calorie alternatives to conventional sugary drinks. This study focused on the use of ultrasonication-enzymatic extraction to produce a low-calorie ready-to-drink Kangra orthodox black tea with the natural sweetener Stevia rebaudiana. By employing sonication time (9 to 45 min) and temperature (35 to 55 °C) as independent variables, statistical analysis revealed significant effects of these parameters on key quality indicators. In the ultrasonicated-assisted enzymatic extraction, the optimal conditions were 27.58 min at 45.06 °C with 0.0095% Tannase, to maximize the water extract content, total phenolic content, antioxidant capacity, caffeine, tannins content, colour, theaflavins, thearubigins, total colour, brightness, a*, b* colour value and overall acceptability and to minimize the pH, tea cream, and colour value L* of the ultrasonicated-assisted enzymatic extraction of Kangra orthodox black tea. The predicted water extract was 47.69%, the total phenolic content was 233.77 µg GAE/100 mL, the antioxidant capacity was 78.50 mM TE/mL, caffeine was 35.30 µg CAE/100 mL, tannins were 167.14 µg TAE/100 mL, theaflavins were 0.88%, thearubigins were 8.49%, the total colour percentage was 9.22%, the brightness was 14.98%, a* was 5.02, b* was 8.88, the overall acceptability was 8.14, the pH was 5.61, tea cream was 0.36 g/100 mL, and the L* colour value was 23.66 under optimum ultrasonication-assisted enzymatic extraction conditions. To improve the overall palatability of the Kangra Orthodox ready-to-drink tea, sugar (7–11° Brix) was utilized to balance the taste. The optimal sugar concentration for ready-to-drink Kangra orthodox tea based on a sensory score of 10° Brix was the highest. The substitution of sucrose with stevia up to 60% led to an equi-sweet taste eliminating any characteristic bitter aftertaste, in addition to a substantial decline in energy value from 31.44 to 15.72 kcal/100 g. A low-calorie Kangra Orthodox ready-to-drink tea beverage was developed that contained a high level of functional compounds at a reduced energy level. This tea offers a healthy alternative to traditional sweetened beverages and is potentially appealing to a broad market of health-conscious consumers. [ABSTRACT FROM AUTHOR]

Leaves of Stevia rebaudiana are rich source of sweet glycosides of steviol. The major glycoside, stevioside, diterpenoid glycoside--is used in India and various countries as a food sweetener for diabetic patients. Its medical use is also reported in various ailments like heart, liver, pancrease etc. Besides this it is also being used against obesity, stomach burn and to lower uric acid levels in blood. In present study the leaf extract with various extract were tested for immunomodulatry properties. We performed MTT assay to check the cell viability and cytotoxicity in peripheral blood mononuclear cell (PBMC) and also calculated the Trolox equivalent values to assess the antioxidant properties of Stevia rebaudiana.. Percent cell viability values of cells were found to be more than 50 percentages with increase in concentration. At higher dose all these extract showed significant inhibitory effects on proliferation. The aqueous extracts shown the maximum value of Trolox equivalent with 1:16 dilution. It means with the increase in the concentration of extract there is substantial increase in antioxidant property or we can assume antioxidant is dose dependent. But in same time cell viability gets reduced with increase in concentration. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana is associated with the production of calorie-free steviol glycosides (SGs) sweetener, receiving worldwide interest as a sugar substitute for people with metabolic disorders. The aim of this investigation is to show the promising role of endophytic bacterial strains isolated from Stevia rebaudiana Egy1 leaves as a biofertilizer integrated with Azospirillum brasilense ATCC 29,145 and gibberellic acid (GA3) to improve another variety of stevia (S. rebaudiana Shou-2) growth, bioactive compound production, expression of SGs involved genes, and stevioside content. Endophytic bacteria isolated from S. rebaudiana Egy1 leaves were molecularly identified and assessed in vitro for plant growth promoting (PGP) traits. Isolated strains Bacillus licheniformis SrAM2, Bacillus paralicheniformis SrAM3 and Bacillus paramycoides SrAM4 with accession numbers MT066091, MW042693 and MT066092, respectively, induced notable variations in the majority of PGP traits production. B. licheniformis SrAM2 revealed the most phytohormones and hydrogen cyanide (HCN) production, while B. paralicheniformis SrAM3 was the most in exopolysaccharides (EPS) and ammonia production 290.96 ± 10.08 mg/l and 88.92 ± 2.96 mg/ml, respectively. Treated plants significantly increased in performance, and the dual treatment T7 (B. paramycoides SrAM4 + A. brasilense) exhibited the highest improvement in shoot and root length by 200% and 146.7%, respectively. On the other hand, T11 (Bacillus cereus SrAM1 + B. licheniformis SrAM2 + B. paralicheniformis SrAM3 + B. paramycoides SrAM4 + A. brasilense + GA3) showed the most elevation in number of leaves, total soluble sugars (TSS), and up-regulation in the expression of the four genes ent-KO, UGT85C2, UGT74G1 and UGT76G1 at 2.7, 3.3, 3.4 and 3.7, respectively. In High-Performance Liquid Chromatography (HPLC) analysis, stevioside content showed a progressive increase in all tested samples but the maximum was exhibited by dual and co-inoculations at 264.37% and 289.05%, respectively. It has been concluded that the PGP endophytes associated with S. rebaudiana leaves improved growth and SGs production, implying the usability of these strains as prospective tools to improve important crop production individually or in consortium. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni, which is a medicinal plant used in the treatment of diabetes, was the focus of this study aiming to investigate its immunomodulatory properties in diabetes. To form the diabetes group, rats were injected intraperitoneally with STZ and rats with blood glucose levels above 200 mg/dL 2 days after STZ injection were included in the diabetes group. To form the stevia and diabetes + stevia groups, stevia was administered daily by gavage to both healthy and diabetic rats for 28 days. At the end of 28 days, the levels of interleukin‐1 beta and tumor necrosis factor‐alpha in the blood were measured by ELISA. CD3, CD4, and CD8 protein levels in the blood were determined by flow cytometry. Rat body weight increased in the diabetes +25 mg/kg bW stevia group compared with the diabetes group. Blood glucose levels were significantly decreased in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (**p <.01). IL‐1β cytokine levels decreased significantly in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (**p <.01). TNF‐α cytokine levels decreased significantly in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (**p <.01). The amount of CD8 + T cells decreased significantly in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (*p <.05). The stevia diet leads to a reduction in peripheral circulating cytotoxic T cells and proinflammatory cytokines interleukin‐1 beta and tumor necrosis factor‐alpha under hyperglycemic conditions. [ABSTRACT FROM AUTHOR]

• Stevia is an industrially and medicinally valued herb from Asteraceae family. • First report on polyamine- and growth inducer-mediated mono-phasic regeneration in liquid medium. • meta -Topolin-putrescine combination enhanced in vitro growth and proliferation. • Cumulative impact on growth and development was assessed via multiple statistical analyses. • Successfully developed mono-phasic in vitro regenerationn protocol with reduced production time. In the present study, a high-frequency simultaneous muliple shoot-root regeneration protocol for stevia using a liquid medium was developed successfully. Shoot tip explants were grown in Murashige and Skoog liquid (MSL) medium supplemented with different cytokinins i.e. , 6-benzyladenine (BA), kinetin (KIN), and meta -Topolin (m T) in three varied concentrations in combination with 4.9 µM indole-3-butyric acid (IBA) to evaluate their performance on mono-phasic growth and development traits. The m T (6.2 µM) + IBA (4.9 µM) combination induced the highest number of de novo shoots, leaves, and roots (6.3, 30.7, and 5.3, respectively) compared to other treatments during the four-week culture. To assess the effect of polyamines and growth inducers on multiple shoot proliferation, shoot tips from optimized multiple shoot cultures were grown individually in putrescine (PUT), spermidine, spermine, silver nitrate, and salicylic acid (at 100–500 µM) supplemented medium for four weeks and compared against control (without polyamines or growth inducers). The cumulative and individual impact of these polyamines and growth inducers on in vitro growth parameters were comprehensively assessed by employing combined jitter plot and box plot, correlation, network plot, principal component analysis, and unweighted pair-group method with arithmetic mean clustering based on the Euclidean distance matrix. Among different treatments, 200 µM PUT exhibited the most promising results in terms of earliest shoot-root formation (4.7 days, 7.0 days), maximum shoot-root proliferation (counting 12.0, 11.0), and elongation (97.3 mm, 50.0 mm), having maximum leaf count (87). This protocol should be useful to meet the ever-increasing consumers' demand for stevia plantlets, a source of commercially valuable natural sweetener. [ABSTRACT FROM AUTHOR]

The current work is devoted to the development of probiotic microencapsulation systems with the co-encapsulation of a plant extract, which can increase the survival of beneficial bacteria and are suitable for potential applications in the enrichment of fermented beverages based on acid whey. The encapsulation process exhibited a high level of effectiveness, achieving 83.0% for Bifidobacterium (BB), 89.2% for Stevia leaf extract (SE), and 91.3% for their combination (BB + SE). The FTIR analysis verified substantial interactions between the encapsulated agents and the polymer matrix, which enhanced the stability of the microcapsules. The BB + SE microcapsules exhibited reduced swelling and moisture content, indicating a denser structure compared to separately encapsulated BB and SE. Comparison of release kinetics of BB, SE and BB + SE loaded microcapsules showed that the combination of active agents has a quicker initial release, reaching 60% release within the first 2 h, and this value increased to 70% after 4 h. The release kinetics studies demonstrated a controlled release of active substances over 24 h. A morphology analysis shows that the surfaces of the dry microcapsules containing BB, SE, and their combination BB + SE have a porous structure. For encapsulated agents, the size of the capsules produced with BB and SE are smaller than those produced with two components (BB + SE), the sizes of which are between 760 µm and 1.1 mm. Modeling of the behavior of microcapsules in a simulated gastrointestinal tract provides information on swelling and active agents release rates as a function of pH in real biological environments. Thus, the new formulations of microcapsules with microorganisms and plant extracts have great potential for the development of fermented whey-based beverages. [ABSTRACT FROM AUTHOR]

Besides all sharing an extraordinary high (i.e., up to ~450 times) sweetening power as compared to sucrose and while presenting strong similarities in their molecular structures, molecules belonging to the family of diterpene glycosides (i.e., the secondary metabolites of Stevia rebaudiana) differ in specific structural details that strongly impact on their levels of sweetness and bitter aftertaste. Given the nutritional and pharmacological benefits of steviol secondary metabolites as natural dietetic and anti-diabetic remedies, extraction and purification of steviol glycosides from plant material are nowadays widely spread among many countries. However, an unpleasant bitter aftertaste, which is linked to a genetic variation in human bitter taste receptors, hampers the full exploitation of such benefits and calls for a prompt improvement in organoleptic property control of stevia products. A deeper understanding of the molecular structure of different steviol glycosides and the consequent development of promptly measurable criteria for the organoleptic performance of their mixtures will support processing optimization and control of taste profiles within desired yields. The present research aimed at establishing Raman spectroscopic algorithms for quantitative characterizations of raw stevia-based sweetener products. First, a series of twelve high-purity diterpene glycosides were analyzed by high spectrally resolved Raman spectroscopy and their spectra analyzed in order to establish a complete Raman library of molecular structures. Then, quantitative spectroscopic parameters were built up and applied to characterize the organoleptic property of five different commercially available samples including the recently developed Rebaudioside M isoform. Raman spectroscopy was confirmed as a versatile analytical technique that could be used for quantitative quality control tasks on the production line and for prompt in situ characterizations of purchased products. [ABSTRACT FROM AUTHOR]

Native to Argentina, Brazil and Paraguay, Stevia rebaudiana is a plant used as a sweetener and member of the Asteraceae family. In addition to having the potential to be a sweetener, stevia is a source of several nutrients that have a positive impact on human nutrition. The leaves of stevia include the chemical, rebaudioside, steviolbioside, and isosteviol and sweeter than sucrose with 0 calories. These steviol glycosides are valued commercially worldwide for their ability to replace sugar in food, drink, and nutraceuticals. They are also thought to have a sweet flavour. An overview of various extraction techniques, phytochemistry and commercial stevia applications is given in this article. a variety of goods, including drinks, bread goods, dairy products, and confections. Numerous researches demonstrate the potential health advantages of stevia against a range of illnesses, including the antimicrobial, anti-obesity, cancer prevention, anti-oxidant, anti-hypertensive and anti-diabetic qualities investigated in this work. According to clinical research, steviol glycosides--an important stevia phytochemical--are safe for ingestion by humans and do not cause either acute or serious toxic effects. This work potentially give an alternative perspective of stevia for the management of human ailments and contribute in creative stevia-based goods. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana (Bertoni), commonly known as stevia, is a sought-after natural sweetener, but its conventional propagation methods are slow and inefficient. This study aims to enhance the in vitro culture for stevia by investigating the impact of different Murashige and Skoog (MS) medium salt strengths and plant growth hormones on growth and rebaudioside A content. Apical bud-containing shoot segments were used as explants and cultured on various semi-solid and liquid MS media formulations, incorporating cytokinins (BAP and Kin), auxins (NAA and IAA), and different MS major salt concentrations (MS full, ½ MS, and ¼ MS). Assessments of shoot growth parameters, root formation, and HPLC analysis for rebaudioside A content were conducted. The optimal conditions for in vitro growth was found to be in the ¼ MS + Kin 3 mg/L + NAA 0.1 mg/L (semi-solid) medium, resulting in significantly improved shoot growth and enhanced 30.04% rebaudioside A content. Genetic fidelity of regenerated plants was confirmed using RAPD and ISSR markers. These findings offer valuable insights for optimizing in vitro propagation of stevia and potentially enhancing rebaudioside A content. [ABSTRACT FROM AUTHOR]

Summary Stevia rebaudiana Bertoni is popular source of plant‐derived low/no‐calorie natural sweeteners (LNCSs), collectively known as steviol glycosides (SGs). Nevertheless, genetic predisposition for targeted biosynthesis of SGs is complex due to multi‐substrate functionality of key uridine diphosphate glycosyltransferases (UGTs). Here, we created a high‐quality monoploid assembly of 1.34 Gb with N50 value of 110 Mb, 55 551 predicted protein‐coding genes, and ~80% repetitive regions in Rebaudioside‐A (Reb‐A) enriched cultivar of S. rebaudiana. Additionally, a haplotype‐based chromosome assembly consisting of haplotype A and haplotype B with an overall genome size of 2.33Gb was resolved, harbouring 639 634 variants including single nucleotide polymorphisms (SNPs), indels and structural variants (SVs). Furthermore, a lineage‐specific whole genome duplication analysis revealed that gene families encoding UGTs and Cytochrome‐P450 (CYPs) were tandemly duplicated. Additionally, expression analysis revealed five tandemly duplicated gene copies of UGT76G1 having significant correlations with Reb‐A content, and identified key residue (leu200val) in the glycosylation of Reb‐A. Furthermore, missense variations identified in the acceptor region of UGT76G1 in haplotype resolve genome, transcriptional and molecular docking analysis were confirmed with resequencing of 10 diverse stevia genotypes (~25X). Gene regulatory network analysis identified key transcription factors (MYB, bHLH, bZIP and AP2‐ERF) as potential regulators of SG biosynthesis. Overall, this study provides haplotype‐resolved chromosome‐level genome assembly for genome editing and enhancing breeding efforts for targeted biosynthesis of SGs in S. rebaudiana. [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]

Summary: High‐fat‐and‐fructose diet (HFFD) is one of the causes of hyperlipidaemia (HLP), which could directly cause serious diseases that are harmful to human health. The phenolic composition of stevia extract (WeiKe) and its effect of different concentrations on glucose–lipid metabolism, oxidative stress, and intestinal microecology in hyperlipidaemia mice were investigated. The results showed that WeiKe could effectively inhibit the increase in body weight and blood glucose levels and regulate lipid metabolism. WeiKe repaired the gut morphology, promoted short‐chain fatty acid (SCFA) production, and improved food digestion and absorption. Furthermore, WeiKe reduced the Firmicutes/Bacteroidetes ratio and increased the relative abundance of Lactobacillus. These results suggested that stevia extract had a potential modulatory effect on HFFD‐induced HLP. [ABSTRACT FROM AUTHOR]

The rapid increase in the worldwide prevalence of obesity and certain non-communicable diseases (NCDs), such as: cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes, has been mainly attributed to an excess of sugar consumption. Although the potential benefits of the synergetic use of sweeteners have been known for many years, recent development based on synthesis strategies to produce sucrose-like taste profiles is emerging where biocatalyst approaches may be preferred to produce and supply specific sweetener compounds. From a nutritional standpoint, high-intensity sweeteners have fewer calories than sugars while providing a major sweet potency, placing them in the spotlight as valuable alternatives to sugar. Due to the modern world awareness and incidence of metabolic diseases, both food research and growing markets have focused on two generally regarded as safe (GRAS) groups of compounds: the sweet diterpenoid glycosides present on the leaves of Stevia rebaudiana and, more recently, on the cucurbitane triterpene glycosides present on the fruits of Siraitia grosvenorii. In spite of their flavor advantages, biological benefits, including: antidiabetic, anticancer, and cardiovascular properties, have been elucidated. The present bibliographical review dips into the state-of-the-art of sweeteners and their role in human health as sugar replacements, as well as the biotransformation methods for steviol gylcosides and mogrosides apropos of enzymatic technology to update and locate the discoveries to date in the scientific literature to help boost the continuity of research efforts of the ongoing sweeteners. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana (Bertoni) is an industrially important herb of immense importance due to its sweetening bioactive compounds, especially rebaudioside A and stevioside. The industrial demand for steviol glycosides is mainly fulfilled by conventional agricultural practices. This resulted in non-uniform steviol glycosides (SGs) accumulation in the produce of S. rebaudiana and it is primarily due to changes in varying climatic conditions, genotypes, and cultivars. Therefore, there is an utmost need for a robust protocol to provide quality planting material to produce metabolite-enriched S. rebaudiana. Ex-vitro acclimatization in fields/natural habitats is believed to be a vital part of determining the fate of regenerated plantlets through micropropagation. In the present investigation, elicitor-treated micropropagated plantlets were allowed to harden for one month; after which percentage survival, growth and leaf biomass yield, chlorophyll fluorescence, biochemical profiling of specialized metabolites, and transcriptional profiling of candidate genes were carried out. A high percentage (80–100%) of acclimatized plants was obtained after 30 days. The 1.5 mg L−1 polyethylene glycol (PEG) treated plants attained higher shoot length (14.10 cm) and maximum leaf biomass (537.60 mg FW and 111.03 mg DW). The Chl fluorescence parameters and pigment content indicated stable photosynthetic efficiency in all conditions. Maximum total SGs were accumulated in 1.5 mg L−1 PEG-treated plants. Expression profiling of SG biosynthetic pathway genes showed an apparent correlation with the metabolite content. The study unveils that 1.5 mg L−1 PEG-treated plants perform better in growth and yield attributes and metabolite accumulation parameters after 1 month of ex-vitro acclimatization. [ABSTRACT FROM AUTHOR]

Depending on the texture of soil, different physicochemical and microbiological parameters are characterized, and these characteristics are influenced by crop cultivation. Stevia, a popular zero-calorie sweetener crop, is widely cultivated around the world on various soil textures. Sandy loam and clay soil show great differences in physicochemical and biological parameters and are often used for Stevia cultivation. To understand the effects of Stevia cultivation on soil physicochemical and biological features, we investigated the changes of physicochemical and microbiological parameters in sandy loam and clay soil following Stevia cultivation. This study was carried out through different physiological and biochemical assays and microbiomic analysis. The results indicated that the sandy loam soil had significantly lower pH and higher nutrient content in the rhizosphere and bulk soils after the Stevia cultivation. The sandy loam soil maintained higher bacterial diversity and richness than the clay soil after Stevia harvest. Beneficial bacteria such as Dongia, SWB02, Chryseolinea, Bryobacter and Devosia were enriched in the sandy loam soil; however, bacteria such as RB41, Haliangium and Ramlibacter, which are unfavorable for nutrient accumulation, predominated in clay soil. Redundancy analysis indicated that the variation in the composition of bacterial community was mainly driven by soil pH, organic matter, total nitrogen, available phosphorus, and microbial biomass phosphorus. This study provides a deeper understanding of physicochemical and microbiological changes in different soil textures after Stevia cultivation and guidance on fertilizer management for Stevia rotational cultivation. [ABSTRACT FROM AUTHOR]

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Abstract Stevia rebaudiana is associated with the production of calorie-free steviol glycosides (SGs) sweetener, receiving worldwide interest as a sugar substitute for people with metabolic disorders. The aim of this investigation is to show the promising role of endophytic bacterial strains isolated from Stevia rebaudiana Egy1 leaves as a biofertilizer integrated with Azospirillum brasilense ATCC 29,145 and gibberellic acid (GA3) to improve another variety of stevia (S. rebaudiana Shou-2) growth, bioactive compound production, expression of SGs involved genes, and stevioside content. Endophytic bacteria isolated from S. rebaudiana Egy1 leaves were molecularly identified and assessed in vitro for plant growth promoting (PGP) traits. Isolated strains Bacillus licheniformis SrAM2, Bacillus paralicheniformis SrAM3 and Bacillus paramycoides SrAM4 with accession numbers MT066091, MW042693 and MT066092, respectively, induced notable variations in the majority of PGP traits production. B. licheniformis SrAM2 revealed the most phytohormones and hydrogen cyanide (HCN) production, while B. paralicheniformis SrAM3 was the most in exopolysaccharides (EPS) and ammonia production 290.96 ± 10.08 mg/l and 88.92 ± 2.96 mg/ml, respectively. Treated plants significantly increased in performance, and the dual treatment T7 (B. paramycoides SrAM4 + A. brasilense) exhibited the highest improvement in shoot and root length by 200% and 146.7%, respectively. On the other hand, T11 (Bacillus cereus SrAM1 + B. licheniformis SrAM2 + B. paralicheniformis SrAM3 + B. paramycoides SrAM4 + A. brasilense + GA3) showed the most elevation in number of leaves, total soluble sugars (TSS), and up-regulation in the expression of the four genes ent-KO, UGT85C2, UGT74G1 and UGT76G1 at 2.7, 3.3, 3.4 and 3.7, respectively. In High-Performance Liquid Chromatography (HPLC) analysis, stevioside content showed a progressive increase in all tested samples but the maximum was exhibited by dual and co-inoculations at 264.37% and 289.05%, respectively. It has been concluded that the PGP endophytes associated with S. rebaudiana leaves improved growth and SGs production, implying the usability of these strains as prospective tools to improve important crop production individually or in consortium.

Salinity poses a perpetual threat to agricultural lands, presenting an ongoing challenge to global food security. The present study aimed to explore the potential benefits of gibberellic acid (GA3) in enhancing stevia’s tolerance to salt stress. The experimental treatments comprised a control group (C) with 0 mM NaCl, salt stress (S) with 80 mM NaCl, 50 ppm of GA3 (G1), 100 ppm of GA3 (G2), as well as combinations of GA3 with salt stress (G1+S and G2+S). Exposure to saline water (80 mM NaCl) significantly decreased plant growth, water status, and photosynthetic attributes. However, it also led to notable increases in proline, glycine betaine, malondialdehyde (MDA), and antioxidant enzyme activities compared to the control treatment. Application of 100 ppm of GA3 effectively alleviated salt stress by enhancing plant performance under saline conditions, as evidenced by increased aerial (54%) and root (31%) dry weights compared to the control. Additionally, GA3 treatment resulted in elevated activities of polyphenol oxidase (24%), peroxidase (12%), superoxide dismutase (31%), and catalase (11%) while reducing MDA content by 41%, electrolyte leakage by 37%, and hydrogen peroxide by 34%. The use of phytohormones such as GA3 emerges as a promising strategy for mitigating salt stress-induced damage. It not only enhances plant performance but also reduces oxidative stress, offering protection against the detrimental effects of soil salinization.

Salinity poses a serious challenge for stevia cultivation to meet growing demand. This study investigates protective supplements for stevia grown under saline conditions. Seedlings were subjected to titanium dioxide nanoparticles (0, 150, and 300 ppm), putrescine (0 and 1 mM), and salt (0, 75, and 150 mM) in a factorial design. Morphological traits (plant height, leaf dry and fresh weight), photosynthetic pigments (chlorophyll a, b, total), proline content, soluble and glycoside sugars (rebaudioside A and stevioside), and antioxidant enzyme activity (catalase and peroxidase) were measured. Higher salt concentrations (150 mM NaCl) reduced plant height, leaf dry and fresh weight, and chlorophyll but increased proline, soluble and glycoside sugars, and antioxidant enzyme activity. Foliar applications of putrescine (1 mM) and TiO2 nanoparticles (150 and 300 ppm) mitigated salt stress by improving growth and physiological properties. Simultaneous application of putrescine (1 mM) and TiO2 nanoparticles (300 ppm) was most effective at enhancing secondary metabolite production, important for the pharmaceutical industry. This study demonstrates protective roles of putrescine and TiO2 nanoparticles for stevia cultivation under saline conditions. [ABSTRACT FROM AUTHOR]

• This work represents the first-ever detailed multiple marker studies in Stevia. • QTL identification is the novelty of the work that will promote stevia breeding. • The QTL identified could be used in the mapping of genes responsible for rebaudioside-A. • Functional polymorphic markers will be useful in genetic dissection of traits. Stevia rebaudiana Bertoni, belonging to the family Asteraceae, is one of the most important perennial medicinal plants. It is used as a no-calorie sweetener therefore; mining of sweetening genes using molecular markers is a thrust area. In the present study combinations of markers were screened. Out of 170 RAPD, 26 ISSR, and 89 EST-SSR primers, it was observed that 36 RAPD, 10 ISSR, and 33 EST-SSR were found to be polymorphic. Using MAPMAKER/EXP version 3.0 b, four linkage groups were constructed spanning a distance of 927.3 cM with an average distance between loci of 16.29 cM. On QTL identification, a total of 53 locations were found for both trait 1 (rebaudioside-A) and trait 2 (stevioside). Among 53 QTL locations of trait 1, two major QTL were found for rebaudioside-A namely, in the marker interval of L67–L71 (ISSR HB-11)–(IISRS-3-L) in LG1 and the marker interval of L38–L40 (Sigma-5383–027)- (Sigma-5383-029) in LG3 at LOD of 2.5 and 2.7, respectively. The map constructed and QTL identified will greatly facilitate further genetic studies. It is hoped that this work will have a practical impact on the advancement of stevia breeding and genome analysis. [ABSTRACT FROM AUTHOR]

Currently, different strategies, including the application of bio-fertilizers, are used to ameliorate the adverse effects posed by salinity stress as the major global problem in plants. Fish waste is suggested as a novel bio-fertilizer to mitigate the effects of biotic and abiotic stresses. In this investigation, an experiment was conducted to investigate the effects by applying different concentrations (0, 5, 10, and 15% (v/v)) of fish waste bio-fertilizer on stevia plants grown under salt stress conditions (0, 20, 40, and 60 mM of NaCl). Results showed that salinity negatively affected growth parameters, the photosynthetic pigments, the relative water content, and the chlorophyll fluorescence parameters while increased the activity of antioxidant enzymes, total phenol, hydrogen peroxide (H2O2), malondialdehyde (MDA), proline, and total carbohydrates compared with control samples. On the other hand, the application of fish waste bio-fertilizer mitigated the effects of salinity stress by enhancing growth and mitigating stress-relative markers, especially at the highest salinity level (60 mM). Overall, fish waste bio-fertilizer could be considered a sustainable, innovative approach for the alleviation of salinity stress effects in plants and, in addition, fish waste bio-fertilizer did not cause more salinity issues, at least with the applied doses and experiment time, which is an imperative aspect. [ABSTRACT FROM AUTHOR]

Extracellular vesicles are secreted by all eukaryotic cells and they have an important role in intercellular signaling. Plant extracellular vesicles (PEVs) are a novel area of research that has gained attention due to their potential implications in biomolecule transport and therapeutic applications. PEVs are lipid bilayer‐enclosed structures that contain a diverse cargo of biomolecules such as proteins and lipids. Moreover, it is known that PEVs have a noticeable therapeutic potential for various conditions such as inflammation and oxidative stress. However, there are critical problems such as removing the endosomes and plant‐derived biomolecules that decrease the standardization and therapeutic efficacy of PEVs. In our study, the aim was to characterize plant cell suspension‐derived extracellular vesicles (PCSEVs) obtained from two different plant cell suspension cultures: Stevia rebaudiana and Vaccaria hispanica. These vesicles were isolated using ultrafiltration and characterized with nanoparticle tracking analysis (NTA) and atomic force microscopy (AFM). The molecular composition of PCSEVs was profiled and the cellular uptake assay was performed. Our results demonstrated that PCSEVs have a spherical shape, less than 200 nm. In the fatty acid analysis, the primary components in PCSEVs were palmitic acid, linoleic acid, and cis‐vaccenic acid. The protein content of Stevia rebaudiana‐derived EVs (SDEVs) was largely associated with proteins involved in extracellular structures and functions. Conversely, Vaccaria hispanica‐derived EVs (HDEVs) displayed a higher presence of cytosolic proteins. These findings contribute to the understanding of PCSEVs and open up potential avenues in extracellular vesicle research, pointing to promising prospects for future innovations in various fields. [ABSTRACT FROM AUTHOR]

Aim: A functional food, herbal jam, developed using Phyllanthus emblica (Amla fruit), Moringa oliefera (Moringa) leaves powder and Stevia rebaudiana (natural sweetener) used as sugar replacer to make low caloric jam that can boost up immunity against COVID-19. Stevia present in the jam made it suitable for diabetic patients. Experimental: A control was developed by replacing stevia with sugar with same composition. The ratios of amla and moringa were altered and the best one was selected on the bases of sensory evaluation using 9-point headonic scale. The jams were characterized at different storage days to check the stability and nutritional composition by carrying proximate analysis and mean values were compared. Results: The energy value calculations showed significant difference between the control jam (sugar based) & optimized jam (stevia based). Sensory evaluation concludes high score value of sugar based jam. Microbial analysis was done using Total Plate Count (TPC) and Yeast Mold Count (YMC). Moreover, studies are required to improve the textural attributes of stevia based jam. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni contains diterpenoid steviol glycosides that have no adverse impact on blood sugar levels despite being 300 times sweeter than sugar. This study aimed to investigate the rate of callus induction from stevia leaves and the content of glycosides when changing the sucrose percentage in the culture medium.. Murashige and Skoog (MS) culture medium supported by 4.0 mg/l naphthalene acetic acid (NAA) and 1.0 mg/l benzyl adenine (BA) was used, and different concentrations of sucrose (2, 3, 4, 5 and 6%) were tested .The extraction of glycosides from leaf and callus tissues was performed by using methanol. Extracted glycosides were analyzed by high-performance liquid chromatography (HPLC). The results showed significant influences of sucrose on callus initiation. The concentration of 3% sucrose had the highest fresh and dry weight. No callus was induced in the MS medium with a high concentration of sucrose (5% and 6%). However, the highest glycoside content, stevioside and rebaudioside were obtained from callus treated with 4% concentration followed by 3% sucrose the treatment . The highest fresh and dry weight average was obtained with a 3% concentration of sucrose, this treatment also increased the concentration of glycosides in the callus twice as much as in the leaves, and concentrations of 3% and 4% of sucrose gave very similar concentrations of glycosides in callus in terms of being double what was found in the leaves something which may aid in the development of a stevia glycosides based industry. [ABSTRACT FROM AUTHOR]

The objective of this study is the development of innovative nanocurcumin-based formulations designed for the treatment and prevention of oxidative stress and diabetes. Nanocurcumin was obtained through a micronization process and subsequently encapsulated within biopolymers derived from corn starch and fenugreek mucilage, achieving encapsulation rates of 75% and 85%, respectively. Subsequently, the encapsulated nanocurcumin was utilized in the formulation of sugar-free syrups based on Stevia rebaudiana Bertoni. The stability of the resulting formulations was assessed by monitoring particle size distribution and zeta potential over a 25-day period. Dynamic light scattering (DLS) revealed a particle size of 119.9 nm for the fenugreek mucilage-based syrup (CURF) and 117 nm for the corn starch-based syrup (CURA), with polydispersity indices PDIs of 0.509 and 0.495, respectively. The dissolution rates of the encapsulated nanocurcumin were significantly enhanced, showing a 67% improvement in CURA and a 70% enhancement in CURF compared with crude curcumin (12.82%). Both formulations demonstrated excellent antioxidant activity, as evidenced by polyphenol quantification using the 2.2-diphenyl 1-pycrilhydrazyl (DPPH) assay. In the evaluation of antidiabetic activity conducted on Wistar rats, a substantial reduction in fasting blood sugar levels from 392 to 187 mg/mL was observed. The antioxidant properties of CURF in reducing oxidative stress were clearly demonstrated by a macroscopic observation of the rats' livers, including their color and appearance. [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]

Drug discovery based on medicinal plants remains an important source of bioactive compounds, many of which have been the basis for new chemical structures for the pharmaceutical and food industries. According to the World Health Organization, about 80% of the worldwide population still depends on plant drugs, and several medicines have been obtained from medicinal plants. Unfortunately, the potential benefits of these plants have led to unscientific exploration of natural resources, a fact that is being globally observed. The aim of this study was to evaluate eleven aromatic medicinal plants and compare them to Azorean Camellia sinensis green tea in terms of antioxidant activity, total phenolics, and flavonoid content, and also to evaluate the possibility of their valorization as a nutraceutical material. The results revealed that Camellia sinensis presented higher values for free radical scavenging activity (FRSA, EC50 = 3.43 µg/mL), ferric reducing antioxidant power (FRAP, EC50 = 5.12 µg/mL), and total phenolic content (TPC, 294.43 mg acid gallic equivalents per g of dry extract (DE)). However, the aromatic medicinal plants also presented significant results in terms of FRSA and FRAP, particularly Aloysia citrodora, Mentha pulegium, and Stevia rebaudiana. For ferric ion chelating (FIC), the highest value was found in Cymbopogon citratus (80.60%). Mentha pulegium and Aloysia citrodora had significant values for TPC (199.15 and 187.15 mg GAE/g DE, respectively), but were lower than the values of Camellia sinensis. For flavonoid content (TFC), the highest value was shown in Achyrocline satureioides (265.75 mg rutin equivalents per g DE). This study revealed the importance of some aromatic medicinal plants in terms of bioactivities, and that their combination with green tea is a perfect blend for added value with beneficial nutraceutical effects for human health. [ABSTRACT FROM AUTHOR]

The leaves of Stevia rebaudiana (Bertoni) are the source of several medicinally important bioactive compounds, including steviol glycosides (SGs), primarily accountable for the sweetness of the plant, and phenolic compounds, which offer a wide variety of therapeutic potential against various diseases. Two separate pot experiments were conducted simultaneously in order to investigate the influence of foliar-spray treatments at different concentrations (40, 80, 120, and 160 mg L−1) of irradiated chitosan (ICH) and irradiated sodium alginate (ISA) on the performance of S. rebaudiana with regard to its growth, physiological activities, and production of steviol glycosides measured at 90 days after planting. The growth and physiological attributes of Stevia were significantly improved as a result of foliar sprays of ICH and ISA. Of the treatments, 80 mg L−1 of ICH and 120 mg L−1 of ISA performed the best and resulted in the highest values of all studied parameters compared to the water-spray control. On area-percentage basis, the respective treatments of ICH and ISA also led to an increase in the leaf contents of steviol glycosides, viz., Stevioside by 57.14% and 51.13% and (Rebaudioside A) by 43.28% and 36.64% respectively, as well as other bioactive compounds of S. rebaudiana leaf such as D-Allose sugar (by 33.17% and 29.98%), Neophytadiene (by 57.40% and 53.21%), and β-amyrin (by 16.31% and 13.81%), respectively, compared to the control treatment. Findings of the present study demonstrated that foliar-sprays of γ-irradiated chitosan and sodium alginate improved growth as well as physiological performance of S. rebaudiana, triggering the production of important steviol glycosides and other bioactive constituents of Stevia through up-regulating the secondary metabolism. [ABSTRACT FROM AUTHOR]

Stevia (Stevia rebaudiana), recognized for its low‐calorie, sugar‐free attributes, and various health benefits, has potential applications beyond human consumption, particularly in agriculture. This study explored the potential uses of Stevia in both agricultural and healthcare contexts by examining its plant‐inhibitory, cytotoxic, and antioxidant effects. The methanolic extract of Stevia leaves was fractionated into hexane, ethyl acetate, chloroform, and water fractions. These fractions were then subjected to the bioassay analyses above and underwent identification of their chemical constituents. The results indicated that the ethyl acetate fraction demonstrated significant inhibitory effects on weed germination and growth of Beggars tick (Bidens frondosa) (100% inhibition at 1000 ppm of dose). This fraction also exhibited the highest antioxidant activity, total phenolic, and total flavonoid contents (IC50 DPPH = 18.67 μg/mL, 103.50 mg GAE/g fraction, and 410.16 mg QE/g fraction, respectively). In contrast, the chloroform fraction showed the highest cytotoxic effect (LC50 = 700.01 ppm) in the brine shrimp (Artemia salina) mortality evaluation. Pearson's correlation analysis revealed a positive correlation among plant inhibitory effects, antioxidant potentials, and phenolic/flavonoid contents of Stevia. FTIR spectra confirmed the presence of phenols and nonpolar components in the ethyl acetate and chloroform fractions. In addition, GC‐MS analysis successfully identified Stevia's key constituents, including tetracontane, hexadecane, hexadecanoic acid, methyl ester in the ethyl acetate fraction, and spiro [4.5] decan‐7‐one and 6‐hydroxy‐4,4,7a‐trimethyl‐5,6,7,7a‐tetrahydrobenzofuran‐2(4H)‐one in the chloroform fraction. This study underscores the potential of S. rebaudiana as a source of natural antioxidants and herbicides, offering valuable insights into its diverse applications in agriculture. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of plant spacing on the growth, yield and chemical composition of stevia grown in Poland. The variable factor was spacings of 50 cm × 30 cm, 45 cm × 25 cm and 30 cm × 30 cm. Seedlings were planted during the first ten days of June, and the plant material was harvested between the 10th and 20th of September. In July and September, seedlings were subjected to biometric measurements, and plant samples were taken for chemical analyses. Plants grown at 50 cm × 30 cm spacing were characterised by an increased content of reducing sugars, nitrates, phosphorous, potassium and magnesium, but the yield of the herb and leaves was smallest. The greatest yield of the herb and leaves was found for the 30 cm × 30 and 45 cm × 25 cm spacings with the lowest mass of single plants. Leaves from plants grown in the 30 cm × 30 cm spacing were also characterised as having the greatest concentration of dry mass and phenolic compounds and the lowest concentration of phosphorus and magnesium. Spacing did not significantly affect the biometric parameters of the plants in July, but in September, a difference was observed in the lateral width and total number of shoots. Spacing did not affect the plant pigment contents in the leaves of stevia. [ABSTRACT FROM AUTHOR]

This study investigated the effects of dry yeast and licorice on the growth and morphology of Stevia rebaudiana. The field experiment on Stevia rebaudiana Bertoni under the wooden cover commenced in 2023 at the Department of Horticulture and Gardening Engineering, University of Tikrit, Iraq. Using three different amounts of ground licorice (0, 5, and 10 g) and three varied quantities of dry yeast (0, 2.5, and 5 g) became factors to assess the response of S. rebaudiana Bertoni to them. The highest ratios of plant height, number of leaves per plant, and leaf thickness had ratings at 55.20 cm, 729 leaves, and 0.370 mm, respectively. The results demonstrated that the treatments involving ground addition with licorice (10 g) were considerably superior. However, when adding the dry yeast to the ground up, the optimal ratios of the previously mentioned qualities rose to 87.04 cm, 737 leaves, and 0.620 mm, respectively. The results showed that the treatments significantly improved plant height, number of leaves, and a leaf’s thickness. The interaction between the dry yeast and licorice had the highest impact, resulting in a 97.50 cm plant height, 789 leaves, and 0.740 mm leaf thickness. These findings suggest that dry yeast and licorice combined can be eco-friendly fertilizers to promote Stevia growth. [ABSTRACT FROM AUTHOR]

The utilization of saline water for irrigating plants in arid and semi-arid regions has become imperative because of the scarcity of water resources. Nevertheless, under salt stress conditions, plants undergo a multitude of variation, which result in delayed growth and adversely affect the plant metabolism. Adopting appropriate and sustainable strategies such as using bio-organic fertilizers from animal and plant waste or integrating microorganisms (symbiotic fungi), can improve plant resilience against salt stress. The purpose of this study was to elucidate the impact of arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis alone and/or combined with compost on growth, nutrient uptake, antioxidant activities, and photosynthesis-related performance of Stevia rebaudiana Bertoni under salt stress conditions. Salt stress negatively affected all studied parameters. However, the application of R. irregulare strain in a substrate amended with 5% compost is more effective in enhancing salt stress tolerance in stevia plants compared to the compost and AMF strain applied separately. The synergistic effect of the co-application of these two biofertilizers under salt stress resulted in increased stomatal conductance (276%), chlorophyll fluorescence (38%), antioxidant enzyme activities, and the uptake of K+ (78%), Ca2+ (117%), and P (149%). In conclusion, the application of compost combined with AMF may be a promising sustainable strategy for improving salt stress resistance in stevia. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni originated in South America, but has gained popularity due to the concentration of sweet steviol glycosides present in its leaves. Stevia is also currently grown on other continents in many countries characterised with warm climate. This research aimed to determine whether different irrigation practices might have a significant influence on the yield and composition of the leaves of stevia plants grown in Poland, in cooler climate than native regions for stevia plants. Stevia plants were grown with four different irrigation regimes: irrigation twice a week, irrigation once a week, irrigation only during times of the drought and not irrigated at all. It was determined that different irrigation regimes have substantial effects on the yield, biometric characteristics and chemical composition of stevia leaves, but none of the irrigation regimes were clearly supreme to the others. Yield of stevia plants that were irrigated once a week or only during the drought times was the highest (2.42–2.58 kg per square meter). Stevia plants that were not irrigated were characterised with the lowest height and lateral width (47.61 and 25.35 cm). Leaves of un-irrigated stevia contained the greatest dry mass content (30.47%) and highest concentration of phenolic compounds (337.88 mg per 100 g of fresh stevia leaves). Stevia plants that were irrigated once or twice a week were characterised with a lower concentration of chlorophylls or carotenoids at the time of the harvest (1.20–1.24 and 2.54–2.58 mg per gram of fresh stevia leaves), but stevia plants that were not irrigated contained a greater amount of chlorophyll and carotenoids (1.58 and 3.17 mg per gram of fresh stevia leaves). [ABSTRACT FROM AUTHOR]

Salinity poses a perpetual threat to agricultural lands, presenting an ongoing challenge to global food security. The present study aimed to explore the potential benefits of gibberellic acid (GA3) in enhancing stevia's tolerance to salt stress. The experimental treatments comprised a control group (C) with 0 mM NaCl, salt stress (S) with 80 mM NaCl, 50 ppm of GA3 (G1), 100 ppm of GA3 (G2), as well as combinations of GA3 with salt stress (G1+S and G2+S). Exposure to saline water (80 mM NaCl) significantly decreased plant growth, water status, and photosynthetic attributes. However, it also led to notable increases in proline, glycine betaine, malondialdehyde (MDA), and antioxidant enzyme activities compared to the control treatment. Application of 100 ppm of GA3 effectively alleviated salt stress by enhancing plant performance under saline conditions, as evidenced by increased aerial (54%) and root (31%) dry weights compared to the control. Additionally, GA3 treatment resulted in elevated activities of polyphenol oxidase (24%), peroxidase (12%), superoxide dismutase (31%), and catalase (11%) while reducing MDA content by 41%, electrolyte leakage by 37%, and hydrogen peroxide by 34%. The use of phytohormones such as GA3 emerges as a promising strategy for mitigating salt stress-induced damage. It not only enhances plant performance but also reduces oxidative stress, offering protection against the detrimental effects of soil salinization. [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]

Stevia rebaudiana could be used to makes to produce nutraceuticals and functional foods instead of sucrose and artificial sweeteners. Due to the nutritional and technological advantages of sucrose, innovative approaches for extracting sweeteners from Stevia leaves have been developed and optimized over the years. The purpose of this study was to evaluate the effect of extractingsteviol glycosides from leaves of a new variety of Stevia rebaudiana that had been pre-treated with ethanol. The extractions were carried out in a semi-contiunous mode in a percolator, evaluating the effects of the proportion of solvent to sample (ratio 1/10 and 1/40) and temperature (30 ℃ and 100 ℃) for leaves pre-treated with ethanol. The Tukey Test (p<0.05) was utilized to identify sweeteners through gas chromatography. The highest temperature and proportion of solvent to sample were the best conditions to get an extract rich in sweeteners (13.93 g/100g of dry extract). Under these conditions, the application of two cycles proved to be sufficient to achieve a satisfactory recovery of glycosides in the extract (~93%), while allowing for a lower solvent consumption. Temperature reduction (30℃) decreases glycoside recovery (15.71%) and mass yield (11.14%) in the first extraction cycle. However, temperature ceased was no longer a significant factor (p<0.05) when the solvent volume was reduced to a 1/10 ratio. It is thought that particles with a smaller diameter could be used to gethigher levels of sweeteners, in future [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bertoni, a no-calorie natural sweetener, contains a plethora of polyphenols that exert antioxidant properties with potential medicinal significance. Due to the variety of functional groups, polyphenols exhibit varying solubility depending on the nature of the extraction solvents (water, organic, or their mixtures, defined further on as hydroalcoholic extracts). In the present study, we performed a systematic review, following PRISMA guidelines, and meta-analysis, synthesizing all available data from 45 articles encompassing 250 different studies. Our results showed that the total phenolic content (TPC) of hydroalcoholic and aqueous extracts presents higher values (64.77 and 63.73 mg GAE/g) compared to organic extracts (33.39). Total flavonoid content (TFC) was also higher in aqueous and hydroalcoholic extracts; meta-regression analysis revealed that outcomes in different measuring units (mg QE/g, mg CE/g, and mg RUE/g) do not present statistically significant differences and can be synthesized in meta-analysis. Using meta-regression analysis, we showed that outcomes from the chemical-based ABTS, FRAP, and ORAC antioxidant assays for the same extract type can be combined in meta-analysis because they do not differ statistically significantly. Meta-analysis of ABTS, FRAP, and ORAC assays outcomes revealed that the antioxidant activity profile of various extract types follows that of their phenolic and flavonoid content. Using regression meta-analysis, we also presented that outcomes from SOD, CAT, and POX enzymatic antioxidant assays are independent of the assay type (p-value = 0.905) and can be combined. Our study constitutes the first effort to quantitatively and statistically synthesize the research results of individual studies using all methods measuring the antioxidant activity of stevia leaf extracts. Our results, in light of evidence-based practice, uncover the need for a broadly accepted, unified, methodological strategy to perform antioxidant tests, and offer documentation that the use of ethanol:water 1:1 mixtures or pure water can more efficiently extract stevia antioxidant compounds. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "The Influence of Ex-Vitro Acclimatization of Elicitor-Treated Stevia rebaudiana (Bertoni), on Growth Biomass, Physiological Traits, Steviol Glycosides Accumulation, and Biosynthesis Pathway Gene Expression Pattern" published in the Journal of Plant Growth Regulation. The correction involves the overlapping of Figures 5 and 6 in the original article, which has been rectified. The corrected figures, along with a statement from the publisher, have been provided. The authors of the article are Ashrita, Shiv Shanker Pandey, and Ashish R. Warghat. [Extracted from the article]

Abstract The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using candy leaf (Stevia rebaudiana) leaves aqueous extract for the first time. UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Fourier transmission infrared (FTIR), and zeta potential were applied to demonstrate strong characterization for the biosynthesized stevia-CuNPs. The UV-visible absorbance at 575 nm of surface plasmon resonance (SPR) was 1.2. The particle size mean diameter was recorded as 362.3 nm with − 10.8 mV zeta potential. The HR-TEM scanning revealed 51.46–53.17 nm and spherical-shaped stevia-CuNPs surrounded by coat-shell proteins. The cytotoxicity and cytocompatibility activity assay revealed that stevia-CuNPs was safe in lower concentrations and had a significant cell viability reduction in higher concentrations. The produced stevia-CuNPs were applied as antimicrobial agents against eight pathogenic bacteria and five fungi strains. The inhibitory action of the stevia-CuNPs was more pronounced in bacteria than in fungi, and they likewise demonstrated further inhibition zones in Staphylococcus aureus (50.0 mm) than in Aspergillus flavus (55.0 mm). With inhibition zone sizes of 50.0 mm and 47.0 mm and 50 µg/ml minimum inhibitory concentration, S. aureus and A. flavus were the most inhibited pathogens. The minimum lethal effect (MLC) estimate for S. aureus was 50 µg/ml, whereas 75 µg/ml for A. flavus. The stevia-CuNPs mode of action was characterized as bactericidal/fungicidal as the ratio of MIC to MLC was estimated to be equal to or less than 2. After all, stevia-CuNPs could be used as an alternative to commercial antibiotics to solve the problem of multidrug-resistant (MDR) microorganisms.

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.