No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Studies on biochemical and medicinal properties of Stevia rebaudiana grown in vitro
Abstract
Stevia rebaudiana commonly called candy leaf belongs to the family of Asteraceae. In this preliminary research, we describe in vitro grown stevia plants in the basal MS medium for the quantification and identification of steviol glycosides by Agilent 1260 High Performance Liquid Chromatography (HPLC). The in vitro plants showed the presence of glycosides, stevioside and rebaudioside A and its percentage by mass were 6.79 % and 3.91 % in 0.01 g of leaf powder. These in vitro plants can be used as a raw material for the production of glycosides in high yield which is of medicinal importance. The different in vitro stevia leaf extracts prepared by using different solvents have shown better antioxidant and antimicrobial activity. For the antimicrobial activity, the ethanolic extract showed zone of inhibition with diameter of 3 to 7 mm on B. subtilis and maximum 1 mm on S. aureus and for the methanolic extract it was 3 to 4 mm for B. subtilis ATCC 6633 and maximum 1 mm for S. aureus. The IC50 value using DPPH assay method for studying antioxidant property of aqueous, ethanolic and methanolic stevia leaf extracts were found to be 68%, 77.77% and 71.17% respectively. The results obtained in the present study indicate that in vitro plants grown only in basal medium possess some similar properties like in vivo plants.
... With the present interest for sustenance supplements having low carbohydrate, least calorie and low sugar content, the stevia plant and its extracts have turned out to be a definitive decision to fight against corpulence, cavities, hypertension, weakness, wretchedness, and furthermore against fungal disease (Dushyant et al., 2014). The sweetener derived from stevia is over to 300 times sweeter than sucrose (Liu et al., 2011;Ramya et al., 2014). Furthermore, the leaf concentrate of stevia has been accounted for elevated amounts of cancer prevention agent and antimicrobial movement (Singh et al., 2012;Taleie et al., 2012;Ramya et al,. ...
... thermore against fungal disease (Dushyant et al., 2014). The sweetener derived from stevia is over to 300 times sweeter than sucrose (Liu et al., 2011;Ramya et al., 2014). Furthermore, the leaf concentrate of stevia has been accounted for elevated amounts of cancer prevention agent and antimicrobial movement (Singh et al., 2012;Taleie et al., 2012;Ramya et al,. 2014). Beside, stevioside has characteristics similar to saccharose, but has no effect on blood sugar, so it is of large industrial and therapeutic value and helpful for diabetes (Andolfi et al., 2006;Earanna, 2007;Dushyant et al., 2014;Ramya et al., 2014). ...
... 2014). Beside, stevioside has characteristics similar to saccharose, but has no effect on blood sugar, so it is of large industrial and therapeutic value and helpful for diabetes (Andolfi et al., 2006;Earanna, 2007;Dushyant et al., 2014;Ramya et al., 2014). ...
p>Sustainable nutrient management with the combination of organic and chemical fertilizer amendment expects a key part in upgrading stevia yield without harming the environment and to build up the nutrient balance with increasing soil fertility. A pot experiment was conducted in the net house of the Department of Agricultural Chemistry, Bangladesh Agricultural University, Mymensingh to study the combined effect of vermicompost (VC) and chemical fertilizer (CF) on the growth, leaf biomass yield and stevioside content of stevia in acid soil. Six combinations of VC and CF were applied following completely randomized design (CRD) with three replications. Results showed that VC along with different rates of CF exerted significant influence on the growth, leaf biomass yield and stevioside content of stevia and postharvest soil fertility. The highest values for most of the parameters were found from the plant receiving VC @ 7.5 t ha−1 along with 50% CF. About 578% higher leaf biomass yield was obtained from the treatment VC7.5+CF50 over control. Stevioside content was increased with the increasing levels of VC up to 7.5 t ha−1 along with 75% of CF and also with the advancement of growth period from 30 to 60 days after planting. The highest amount of stevioside (11.05%) was detected in the leaves of plant of the same treatment at harvest. Soil acidity was significantly decreased with the increased levels of VC and CF where as soil fertility in terms of organic matter and nutrient content was increased. Considering the overall performance, farmers may be advised to cultivate stevia in acid soil applying VC @ 7.5 t ha−1 along with 50% chemical fertilizer to boost up stevia production under the agroclimatic condition of the study area in the context of Bangladesh
J. Bangladesh Agril. Univ. 16(1): 73-81, April 2018</p
... Recently, Stevia grown under laboratory condition exhibited the presence of steviosides such as glycosides, steviosides, and rebaudioside. The ethanolic extract of these plants exhibited various medicinal properties including antioxidant and antimicrobial property [12]. Stevia plant contains a well-known non calorie natural sweetener stevioside [13]. ...
... Further, the lead fraction also exhibited strong antioxidant activity via free radical scavenging activity. The antioxidant activity of this methanolic extract (88.48%) was better than that of antioxidant activity reported from earlier Stevia extract (71.75% and 86.4%) [12,31]. Following scavenging reaction, there was a noticeable change in color from purple to yellow. ...
... Following scavenging reaction, there was a noticeable change in color from purple to yellow. The change in color was due to the reaction of the extract with the antioxidant molecule which ultimately resulted in the scavenging of the radical by hydrogen donation [12]. Stevia has been reported to have antioxidant and antidiabetic properties in diabetic mice [32]. ...
Aim: The present communication explores a lead fraction from methanolic extract of novel
Stevia species raised under in vitro conditions for its various biological activities.
Methods: The dried Stevia leaves were crushed in methanol to get polar extract. This
methanol extract was tested for pancreatic lipase and alpha amylase inhibitory activity
using quantitative plate assays. Antibacterial property of the extract was also evaluated
against S. epidermidis, E.coli, B subtilise, S. aureus and P. aeruginosa. Futher, the
antioxidant potential was evaluated using DPPH.
Results: The methanolic extract inhibited pancreatic lipase with IC 50 of 5.74 µg/ml in a
similar manner to a well known anti obesity drug in the market Orlistat. The methanolic
extract also showed a better pancreatic α-amylase inhibitory activity (IC 50 = 88 µg/ml) than
Acarbose. Further, the lead fraction exhibited 88.48% antioxidant activity. It also exhibited
broad spectrum antimicrobial activity against the spectrum of Gram positive and Gram
negative bacteria tested under laboratory conditions with a MIC ranging from 1.95-31.25
µg/ml.
Conclusion: Thus, the present study signifies the vast potential of the lead fraction from a
novel Stevia species for further development into a herbal formulation for prevention of
various infectious and non infectious diseases.
Keywords: enzyme inhibitor, Stevia, antioxidants, minimal inhibitory concentration
... They can be used as a sweetening agent in all foods because they are highly stable at high temperatures and in acid environments. Beside, stevioside has characteristics similar to saccharose, but has no calories and no effect on blood sugar, so it is of large industrial and therapeutic value and helpful for diabetes (Farooqi and Sreeramu 2001;Megeji et al. 2005;Andolfi et al. 2006;Earanna 2007;Dushyant et al. 2014;Ramya et al. 2014). The sweetener isolated from the leaves of Stevia is up to 300 times sweeter than sucrose (Megeji et al. 2005;Liu et al. 2011;Ramya et al. 2014). ...
... Beside, stevioside has characteristics similar to saccharose, but has no calories and no effect on blood sugar, so it is of large industrial and therapeutic value and helpful for diabetes (Farooqi and Sreeramu 2001;Megeji et al. 2005;Andolfi et al. 2006;Earanna 2007;Dushyant et al. 2014;Ramya et al. 2014). The sweetener isolated from the leaves of Stevia is up to 300 times sweeter than sucrose (Megeji et al. 2005;Liu et al. 2011;Ramya et al. 2014). Furthermore, the leaf extract of Stevia has been reported to contain high levels of antioxidant and antimicrobial activity Taleie et al. 2012;Ramya et al. 2014). ...
... The sweetener isolated from the leaves of Stevia is up to 300 times sweeter than sucrose (Megeji et al. 2005;Liu et al. 2011;Ramya et al. 2014). Furthermore, the leaf extract of Stevia has been reported to contain high levels of antioxidant and antimicrobial activity Taleie et al. 2012;Ramya et al. 2014). ...
PurposeA comparative study was carried out to assess the impact of vermicompost leachate (VCL) and inorganic fertilizer either alone or in combination on growth and biochemical parameters in Stevia rebaudiana (Bertoni) through a soilless culture system. Methods
The cattle manure-based vermicompost was processed by earthworms and the resulting leachate was brewed for 48 h and then collected in the system reservoir for use in soilless culture. An inorganic fertilizer was also prepared by dissolving a water soluble fertilizer in distilled water. ResultsMost of the parameters measured were influenced by fertilizer type and growth media. The results indicated that VCL could increase some growth attributes like biomass production, plant height and leaf area, but not as much as what observed in the combined treatment of inorganic fertilizer and VCL. Whereas the carbohydrate content of the leaves did not significantly change in all fertilizer type treated plants, the photosynthetic efficiency and the activities of superoxide dismutase (SOD), (proxidase) POX and (catalase) CAT markedly increased in VCL treated plants. Conclusion
Due to the equivalent effects of both VCL and inorganic fertilizer in the current investigation, it could be suggested that replacing inorganic fertilizer with VCL or developing an equilibrated fertilization strategy that combines the proper ratios of inorganic fertilizer and VCL could be justified for sustainable Stevia cultivation.
... With the present interest for sustenance supplements having low carbohydrate, least calorie and low sugar content, the stevia plant and its extracts have turned out to be a definitive decision to fight against corpulence, cavities, hypertension, weakness, wretchedness, and furthermore against fungal disease (Dushyant et al., 2014). The sweetener derived from stevia is over to 300 times sweeter than sucrose (Liu et al., 2011;Ramya et al., 2014). Furthermore, the leaf concentrate of stevia has been accounted for elevated amounts of cancer prevention agent and antimicrobial movement (Singh et al., 2012;Taleie et al., 2012;Ramya et al,. ...
... thermore against fungal disease (Dushyant et al., 2014). The sweetener derived from stevia is over to 300 times sweeter than sucrose (Liu et al., 2011;Ramya et al., 2014). Furthermore, the leaf concentrate of stevia has been accounted for elevated amounts of cancer prevention agent and antimicrobial movement (Singh et al., 2012;Taleie et al., 2012;Ramya et al,. 2014). Beside, stevioside has characteristics similar to saccharose, but has no effect on blood sugar, so it is of large industrial and therapeutic value and helpful for diabetes (Andolfi et al., 2006;Earanna, 2007;Dushyant et al., 2014;Ramya et al., 2014). ...
... 2014). Beside, stevioside has characteristics similar to saccharose, but has no effect on blood sugar, so it is of large industrial and therapeutic value and helpful for diabetes (Andolfi et al., 2006;Earanna, 2007;Dushyant et al., 2014;Ramya et al., 2014). ...
p>In view of the growing awareness about eco-friendly organic farming, vermicompost (VC) could be a very good option for increasing crops yield. The organic carbon in VC releases nutrients slowly and steadily into the system and enables the plant to absorb these nutrients. To assess the effect of VC on soil fertility, growth and yield of stevia in acid and non-calcareous soils, an experiment was undertaken in the net house of the Department of Agricultural Chemistry, Bangladesh Agricultural University, Mymensingh, during February to May, 2012. Four levels of VC viz. 0, 5, 7.5 and 10 t ha-1 in two contrasting soils (Acid and Non-calcareous) were examined following CRD with three replications. Growth and yield attributes such as plant height, branch and leaf number, leaf area, fresh and dry weight of leaves were significantly influenced by different levels of VC. All the plant parameters increased with the advancement of growth period as well with increased rate of VC up to 7.5t ha-1 and then declined with further additions. The leaf biomass yield was 335% and 338% higher in acid soil and in non-calcareous soil, respectively over control. The overall performance of non-calcareous soil was superior to acid soil in terms of both plant and soil parameters studied. The acidity of both soils significantly decreased with the increased application of VC ranging from 4.9 to 5.7 in acid soil and 6.5 to 7.2 in non-calcareous soil. Total N, available P, exchangeable K, Ca, Mg, available S, Zn, B were also significantly increased with the increased levels of VC up to its highest level (VC @ 10t ha-1) in both soils. Thus the results suggest that VC @ 7.5t ha-1 should be applied for getting maximum leaf biomass yield of stevia and 10t ha-1 for increasing the fertility of both soils under the agro-climatic conditions of the studied area.
J. Bangladesh Agril. Univ. 13(2): 169-174, December 2015</p
... The screening on biological activities showed that O. aristatus has antioxidant properties (Vijayan et al. 2017). Studies showed that the ethanolic extract of S. rebaudiana has high antimicrobial and antioxidant properties (Ramya et al. 2014). In Malaysia, a study conducted using normal and streptozotocin-induced hyperglycemic rats showed that the aqueous extract of S. crispus tea has antihyperglycemic activities (Fadzelly, Asmah & Fauziah 2006). ...
In line with the growing health trend in Malaysia, more consumers drink herbal tea for medicinal benefits. However, herbal tea products could be contaminated with polycyclic aromatic hydrocarbons (PAHs) from various production sources. There is a little study focused on the detection of PAHs in herbal tea species distributed in Malaysia. This study was performed to investigate PAHs content and toxicity in selected commercial herbal teas in Malaysia. A total of seven different Malaysian herbal tea samples were extracted using QuEChERS extraction method and the contamination level of PAHs were evaluated using gas chromatography (GC) with a flame ionization detector (FID). The total content of 10 PAHs (∑10PAHs) in the herbal tea samples ranged from 2.53 to 9.39 µg/kg. Acenaphthene, fluorene, phenanthrene and anthracene were the most abundant compounds with 53% contribution of all PAHs content. All tested herbal teas species showed low toxic equivalency (TEQ) values ranging from 0.0027 to 0.1148. The least contaminated samples were Strobilanthes crispus, Senna alata, Orthosiphon aristatus, Clinacanthus nutans, and Stevia rebaudiana.
... It also enhances weight reduction, prevents dental caries, and has antimicrobial properties. It is non-carcinogenic, a quality distinguishing it from artificial sweeteners [ 6 ]. The favourable soil and climatic conditions in Bulgaria also allow the successful growth of S. rebaudiana, but only as an annual plant because rhizomes cannot survive in low soil temperatures in winter. ...
Stevia rebaudiana Bertoni is important medicinal plant which is native between southern Brazil and northern Paraguay. A reliable protocol for shoot organogenesis and regeneration was developed for an antidiabetic medicinal plant species. Regeneration via indirect shoot organogenesis was established from two types of explant (leaf and stem) on MS medium [1] with different concentrations and combinations of plant growth regulators (PGR) such as 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP) and gibberellic acid (GA3) for inducing organogenic callus of S. rebaudiana. In the present investigation the highest percentage of response was shown by 90% and 80% callogenesis from leaf and stem explants on MS medium supplemented with 2.0 mg/l 2,4-D + 0.5 mg/l BAP + 0.5 mg/l GA3 (MSC3) was observed. The high frequency of regenerants was observed from S. rebaudiana leaves at 0.5 mg/l 2,4-D + 2.0 mg/l BAP + 0.5 mg/l GA3 (MSR3). Optimal shoot multiplication and rooting were obtained on 2.0 mg/l BAP and 0.1 mg/l indole- 3-butyric acid (IBA), respectively, followed by successful acclimatization of regenerants (90% survival) to greenhouse condition. The purpose of this study was to establish a reliable S. rebaudiana regeneration protocol that can be used to facilitate the cultivation, propagation and planting of this plant species.
... Besides their sweetening properties, stevia extracts possess many potential therapeutic effects such as hypotensive, hypoglycemic, anti-inflammatory, anti-tumor, and immunomodulatory effects [14]. Also, stevia contains several phenolic compounds such as flavonoids, and phenolics which possess important antioxidant properties [15]. Few studies have investigated the neuroprotective effects of stevia extract and its derivatives against scopolamine-induced learning and memory deficits [16] and fructose-induced neuronal damage in the hippocampus, amygdala, and spinal cord [17]. ...
The current study investigated the effects of stevia extracts on a PTZ-induced epileptic rat model and its potential mechanism. Thirty male Sprague-Dawley rats were equally subdivided into 3 groups; (1) normal control (NC) group, (2) PTZ-group: received PTZ (50 mg/kg, i.p. every other day) for 2 weeks, and (3) PTZ+ Stevia group: received PTZ and stevia (200 mg/kg orally daily) for 4 weeks (2 weeks before the start of PTZ treatment and 2 weeks with PTZ administration). The first jerk latency and the seizure score were assessed in rats. Also, brain tissue samples were collected by the end of the experiment, and oxidative stress markers (catalase, MDA, and total antioxidant capacity (TAC)) were measured by biochemical analysis in hippocampal brain homogenates. Also, in the hippocampus, the expression of IL6 and Bcl-2 at the mRNA level and expression of Sirt-1, P53, caspase-3, GFAP, and NF-kB in CA3 hippocampal region by immunohistochemistry was investigated. PTZ substantially increased the seizure score and decreased the seizure latency. Also, PTZ significantly increased MDA, GFAP, IL-6, NF-kB, caspase-3, and p53 and significantly reduced Sirt-1, TAC, and Bcl-2 in hippocampal tissues compared to the control group (p < 0.01). However, Stevia Rebaudiana Bertoni (Stevia R.) significantly attenuated the PTZ-induced seizures, improved oxidative stress markers, downregulated GFAP, IL-6, NF-kB, caspase-3, and p53, and upregulated Sirt-1 and Bcl-2 in the CA3 hippocampal region (p < 0.01). In conclusion, Stevia R. exhibits neuroprotective and antiepileptic actions in PTZ-induced epilepsy due to its antioxidant, anti-apoptotic, and anti-inflammatory effects. Additionally, the Sirt-1 pathway might be involved in the antiepileptic and neuroprotective effects of stevia in PTZ-kindled epileptic rat model.
... Besides their sweetening properties, stevia extracts possess many potential therapeutic effects such as hypotensive, hypoglycemic, anti-inflammatory, anti-tumor, and immunomodulatory effects [14]. Also, stevia contains several phenolic compounds such as flavonoids, and phenolics which possess important antioxidant properties [15]. Few studies have investigated the neuroprotective effects of stevia extract and its derivatives against scopolamine-induced learning and memory deficits [16] and fructose-induced neuronal damage in the hippocampus, amygdala, and spinal cord [17]. ...
The current study investigated the effects of stevia extracts on a PTZ-induced epileptic rat model and its potential mechanism. Thirty male Sprague-Dawley rats were equally subdivided into 3 groups; (1) normal control (NC) group, (2) PTZ-group: received PTZ (50 mg/kg, i.p. every other day) for 2 weeks, and (3) PTZ+ Stevia group: received PTZ and stevia (200 mg/kg orally daily) for 4 weeks (2 weeks before the start of PTZ treatment and 2 weeks with PTZ administration). The first jerk latency and the seizure score were assessed in rats. Also, brain tissue samples were collected by the end of the experiment, and oxidative stress markers (catalase, MDA, and total antioxidant capacity (TAC)) were measured by biochemical analysis in hippocampal brain homogenates. Also, in the hippocampus, the expression of IL6 and Bcl-2 at the mRNA level and expression of Sirt-1, P53, caspase-3, GFAP, and NF-kB in CA3 hippocampal region by immunohistochemistry was investigated. PTZ substantially increased the seizure score and decreased the seizure latency. Also, PTZ significantly increased MDA, GFAP, IL-6, NF-kB, caspase-3, and p53 and significantly reduced Sirt-1, TAC, and Bcl-2 in hippocampal tissues compared to the control group (p < 0.01). However, Stevia Rebaudiana Bertoni (Stevia R.) significantly attenuated the PTZ-induced seizures, improved oxidative stress markers, downregulated GFAP, IL-6, NF-kB, caspase-3, and p53, and upregulated Sirt-1 and Bcl-2 in the CA3 hippocampal region (p < 0.01). In conclusion, Stevia R. exhibits neuroprotective and antiepileptic actions in PTZ-induced epilepsy due to its antioxidant, anti-apoptotic, and anti-inflammatory effects. Additionally, the Sirt-1 pathway might be involved in the antiepileptic and neuroprotective effects of stevia in PTZ-kindled epileptic rat model.
... The natural sweeteners in S. rebaudiana are appropriate for people who should control the concentration of sugar in their blood (Deshmukh and Ade, 2012;Jagatheeswari and Ranganathan, 2012). In addition, it is non-carcinogenic (Ramya et al., 2014), an attribute distinguishing it from artificial sweeteners. This fact has increased its demand in the national and international markets, and in Mexico an increase in its crop surface has been suggested. ...
Objective: To evaluate various explants and growth regulators in order to improve invitro propagation of Stevia rebaudiana through organogenesis.Design/Methodology/Approach: Explants and growth regulators in two differentconcentrations were evaluated. The explants were nodal segment, axillary bud, andapical meristem; while the growth regulators were benzylaminopurine (BAP) at 1.125 mgL -1 and 3.0 mg L -1 , naphthaleneacetic acid (NAA) at 1.5 mg L -1 and 3.0 mg L -1 , andCIDEF-4 brassinosteroids (BRs) at 1.0 mg L -1 and 1.5 mg L -1 . In total 18 treatments withseven repetitions. Contamination, oxidation, and survival were recorded duringinduction; while leaf number, regrowth height, and root presence were recorded duringmultiplication.Results: At the induction stage there was a differential response between explantsaccording to their ontogenetic age; during multiplication, the morphological componentsshowed differences between concentrations of growth regulators and explants, withhigher effectiveness when adding BAP to apical meristems.Study Limitations/Implications: Both the origin and the age of explants can inducedifferential growth while interacting with growth regulators. Findings/Conclusions: Apical meristem explants showed better advantages for in vitroreproduction of S. rebaudiana since they present less contamination and higher survivalat the induction stage, even when exhibiting the highest oxidation among explants,which did not influence the decrease in their survival. At the multiplication stage withapical meristem, height, leaf number, and root presence were increased. Values werehigh when interacting with BAP.
... properties, stevia extracts possess other therapeutic effects such anti-hyperglycemic, anti-hypertensive, anti-inflammatory, anti-tumor, anti-diarrhea, diuretic and immunomodulatory effects (Chatsudthipong and Muanprasat, 2009). Also, stevia contains phytochemical compounds that help to reduce blood sugar, cholesterol and blood pressure and phenolic compounds such as flavonoids, phenolics are known to possess potential antioxidant properties (Shukla et al., 2011;Ramya et al., 2014) . The steviol glycosides which include as rebaudioside A and stevioside are the cause of their sweetness and stevioside differs from rebaudioside A by having one less glucose moiety (Wheeler et al., 2008) . ...
This study was carried out to evaluate effect of stevia extracts and some of its derivatives (chlorogenic acid, CGA and stevioside, S) on metabolic dysfunctions and contractile functions of soleus muscle and glucose transporter 4 (GLUT4) expression in STZ-induced type 1 diabetic rats. Forty-eight male Sprague Dawely rats were divided into 6 equal groups 1) normal control (NC) group; normal rats received 0.75 ml normal saline, 2) DM groups; diabetic rats received 0.75 ml normal saline, 3) DM+ I(insulin); as DM group but rats received 1.0 IU mixtard insulin/100 g, 4) DM + MSE group; as DM but rats received 200 mg/ kg of methanolic extract of stevia, 5) DM+ S as DM but rats received 2 mg /kg of pure stevioside and 6) DM+ CGA as DM but rats received 10 mg / kg of pure chlorogenic acid. Four weeks after drug treatment, serum fasting glucose, insulin and lipid parameters (TG, TC, LDL and HDL), the expression of GLUT4 by real time PCR and contractile parameters of soleus muscle of rats were measured. DM showed significant increase in FBS, LDL, TG and TC with significant decrease in fasting insulin, HDL, GLUT4 expression and contractile parameters of soleus muscle (p< 0.05). Treatment with MSE, stevioside or CGA caused significant decrease in FBS, LDL, TG and TC and significant increase in fasting insulin, HDL, GLUT4 expression and contractile parameters of soleus muscle (p< 0.05). We concluded that STZ-induced type 1 MD is manifested by hyperglycemia and dyslipidemia and impaired contractile functions of slow type skeletal muscle fibres with down regulation GLUT4 expression. These deleterious effects might be corrected by treatment with methanolic stevia extracts, pure stevioside or CGA.
... Stevia also contains phytochemical compounds e.g. stevioside, rebaudioside A and steviol that help to reduce blood sugar, cholesterol and blood pressure, and flavonoids and phenolics compounds such as SR-3, SR-1, SR-5, SR-2 are known to possess potential antioxidant properties (Ramya et al., 2014). The present work was therefore designed to study the effects of muscle exercise and methanolic stevia extracts and a combination of both on the outcome of renal I/R injury in a rat model. ...
... Stevia also contains phytochemical compounds e.g. stevioside, rebaudioside A and steviol that help to reduce blood sugar, cholesterol and blood pressure, and flavonoids and phenolics compounds such as SR-3, SR-1, SR-5, SR-2 are known to possess potential antioxidant properties (Ramya et al., 2014). The present work was therefore designed to study the effects of muscle exercise and methanolic stevia extracts and a combination of both on the outcome of renal I/R injury in a rat model. ...
Background:
The present work was designed to study the effects of methanolic stevia extracts and aerobic exercise and combination of both on renal I/R injury in male rats.
Methods:
60 adult male Sprague-Dawley rats were subdivided into five equal groups as sham, control, exercise, stevia, and stevia plus exercise group. After 5 weeks of exercise and stevia, animals were exposed to 45 min of left renal ischemia and right nephrectomy followed by reperfusion. Serum creatinine, creatinine clearance, fractional Na excretion (FENa+), malondialdehyde (MDA), reduced glutathione (GSH) and catalase (CAT) levels in kidney tissues were measured. Also, renal histopathology and the expression of caspase-3 by immunohistochemical examination were done.
Results:
The results showed that stevia, exercise or combination of stevia and exercise caused a significant decrease in serum level of creatinine (p < 0.001) and FENa+ (p < 0.001) and an increase in creatinine clearance (p < 0.001). Moreover, this caused a significant decrease in (MDA; p < 0.046) and an increase in GSH (p < 0.01) and CAT (p < 0.01), as well as causing a significant decrease in caspase 3 expression compared to the control group.
Conclusions:
Pretreatment with either stevia or exercise of combination of both seem to have protective effects on renal I/R injury. However, the protective effect of exercise against renal I/R injury seems to be less than stevia. These effects might be due to attenuation of oxidative stress and apoptosis in kidney tissues.
... properties, stevia extracts possess other therapeutic effects such anti-hyperglycemic, anti-hypertensive, anti-inflammatory, anti-tumor, anti-diarrhea, diuretic and immunomodulatory effects (Chatsudthipong and Muanprasat, 2009). Also, stevia contains phytochemical compounds that help to reduce blood sugar, cholesterol and blood pressure and phenolic compounds such as flavonoids, phenolics are known to possess potential antioxidant properties (Shukla et al., 2011;Ramya et al., 2014) . The steviol glycosides which include as rebaudioside A and stevioside are the cause of their sweetness and stevioside differs from rebaudioside A by having one less glucose moiety (Wheeler et al., 2008) . ...
This study was carried out to evaluate effect of stevia extracts and some of its derivatives (chlorogenic acid, CGA and stevioside, S) on metabolic dysfunctions and contractile functions of soleus muscle and glucose transporter 4 (GLUT4) expression in STZ-induced type 1 diabetic rats. Forty-eight male Sprague Dawely rats were divided into 6 equal groups 1) normal control (NC) group; normal rats received 0.75 ml normal saline, 2) DM groups; diabetic rats received 0.75 ml normal saline, 3) DM+ I(insulin); as DM group but rats received 1.0 IU mixtard insulin/100 g, 4) DM + MSE group; as DM but rats received 200 mg/ kg of methanolic extract of stevia, 5) DM+ S as DM but rats received 2 mg /kg of pure stevioside and 6) DM+ CGA as DM but rats received 10 mg / kg of pure chlorogenic acid.
... Furthermore, an upsurge of interest in the therapeutic potential of plants and their addition to food products has been observed, with an increased interest in the use of the natural sweetener Stevia rebaudiana Bertoni (Korir et al., 2014). Stevia leaves have been shown to exert antioxidant and antimicrobial activity and could be a useful tool to ensure safety and quality of food products (Ramya et al., 2014). dramatic impact on color quality and may also affect nutritional properties (Guo et al., 2014). ...
A fruit juice-stevia beverage was processed using pulsed electric fields (PEF), a non-thermal preservation technology, with the purpose of investigating the feasibility of PEF for bioactive compounds and steviol glycosides enhancement and its impact on physicochemical properties. Variable ranges of response surface methodology were 20–40 kV/cm (electric field strength), 100–360 μs (treatment time) and 0-2.5% (w/v) stevia. After PEF, ascorbic acid was retained by more than 74%. Some of the analyzed PEF treatments resulted in an enhancement of total anthocyanins and carotenoids. The best results for rebaudioside A/stevioside ratio were obtained when PEF was applied at 30 kV/cm for 230 μs. Hydroxymethylfurfural content and total color differences were maximum at the highest electric field strength assayed (40 kV/cm). PEF conducted at 21 kV/cm during 360 μs with 2.5% stevia led to the beverage with the greatest content in bioactive compounds and sweetening properties with minimal color changes.
... Stevia rebaudiana (Bertoni) is a small perennial herb belonging to the family Asteraceae [1]. The plant is native to Paraguay and Brazil, and produces high potency low calorie sweeteners, stevioside and rebaudioside which are about 250-300 times sweeter than sucrose [2,3,4,5]. ...
Stevia rebaudiana (Bertoni) Bertoni (Asteraceae) is a small perennial herb which is widely cultivated for its sweet leaves and possesses 250-300 times the sweetness than sucrose due to the presence of steviol glycosides (mainly stevioside and rebaudioside). It is commonly known as candy leaf, sweet leaf and sugar leaf. Even though, this plant has been studied extensively for its sweetness, information on therapeutically important active components presence in stevia is scattered or lacking. Therefore, the present study was undertaken to determine the distribution of Total Phenolic Content (TPC), Total Flavonoid Content (TFC) and Total Antioxidant Capacity (TAC) of different parts and different leaf positions of S. rebaudiana. Leaf fresh weight, dry weight and leaf area at different leaf positions were recorded. The TAC, TPC and TFC were determined using Ferric Reducing Antioxidant Power Assay (FRAP), modified Folin-Ciocalteu colorimetric method and calorimetric method respectively. Leaf fresh weight and leaf dry weight were increased with the maturity. All tested plant parts demonstrated the presence of TPC, TFC and TAC. The significantly higher TPC, TFC and TAC were reported in leaves than other parts of plant. The order of increase of active components was leaf>flower>stem>branch>root. TPC, TFC and TAC of different leaf positions revealed that TAC, was decreased gradually from immature to mature leaf (1 st leaf>2 nd leaf>3 rd leaf>4 th leaf>5 th leaf). Moreover, all tested phytochemicals (phenolics and flavonoids) and antioxidant capacity were significantly higher in extracts prepared from the first leaf. Interestingly, a strong significant correlations were observed between TAC and tested secondary metabolites (TFC, R 2 =0.85). The results of the present study are vital important in cultivation, harvesting and quality control aspects of S. rebaudiana.
... The main steviol glycosides found in Stevia are stevioside (4-13% of dry weight leaves) with a sweetening power of 200 to 300, and rebaudioside A (2-4%), with a sweetening power of 250 to 450 (Mehrotas, 2014). Besides sweetening properties, Stevia leaves are also considered to possess antioxidant, antimicrobial, and antifungal activities (Ramya, Manogaran, Joey, Keong, & Katherasan, 2014). ...
The aim of this work was to investigate the potential use of non-conventional technologies (microwaves, ultrasounds, pulsed electric fields and high voltage electrical discharges) to enhance the extraction of high-added value compounds (mainly stevioside and rebaudioside A), and antioxidants (total phenolic compounds, flavonoids, chlorophylls, and carotenoids), from Stevia rebaudiana leaves. After treatment at equivalent energy, a supplementary diffusion was performed until 1 h. Results demonstrated that when water (100%) was used as solvent, the maximum recovery of stevioside (50.8±0.1 mg/g) was obtained after ultrasound-assisted extraction, while microwave allowed the highest yields of rebaudioside A (22.7±0.1 mg/g). However, pulsed electric field technology was the most efficient technology to recover stevioside (44.2±0.1 mg/g) and rebaudioside A (22.4±0.3 mg/g) when using 50% ethanol-water. Results obtained through this work pave the way toward the possible scaling-up of some of these non-conventional technologies for a multistep selective extraction of valuable compounds from Stevia leaves.
... Furthermore, an upsurge of interest in the therapeutic potential of plants and their addition to food products has been observed, with an increased interest in the use of the natural sweetener Stevia rebaudiana (Stevia) Bertoni [1]. Stevia leaves have been shown to exert antioxidant properties, which stem from their high levels of flavonoids and phenolic compounds [2]. ...
During the processing of liquid foods, ascorbic acid may be altered, thus reducing beneficial health effects. For this reason, the degradation kinetics of ascorbic acid were determined in a fruit juice mixture (papaya and mango) sweetened with Stevia rebaudiana (SR) infusion after treatment by pulsed electric field (PEF) processing. The variable ranges were 20-40 kV/cm (electric field strength, E) during 100-360 μs (time treatment, t). The degradation equation was AA (mg/100 mL) = 26.842 - 0.101·E - 0.003·t- 10.371·%Stevia + 2.865·%Stevia2, demonstrating the use of PEF as an alternative to pasteurization treatments. However, results show the need to optimize treatment conditions whenever there is a change in the matrix (food) or some processing factor.
... They can interfere with the oxidation process, chelating catalytic metals and also act as oxygen scavengers (Lemus-Mondaca et al., 2012). Antioxidant-based drug formulations can be used for the prevention and treatment of complex diseases like atherosclerosis, stroke, diabetes, Alzheimer's disease and cancer (Ramya et al., 2014). Biologically active substances found in plants also exhibit effects on macrophages which play central role in inflammatory diseases and produce many pro-inflammatory cytokines, such as interleukin-6 (IL-6), tumor necrosis factor-(TNF-), and interleukin-1 (IL-1). ...
Preparation of stevia chocolate is an innovative, futuristic research in the field of functional food preparation which may enhance the medicinal value without an adverse effect to the human health. During the research, chocolate were prepared with natural sweetener stevia and its effect were investigated. The chocolate is prepared using cocoa powder, milk powder, stevia, unsalted butter, cocoa butter, cranberries and agar-agar. Two samples were made by addition of starch as a bulking agent. For flavor enhancement cranberry was chosen for the all sample preparation. On the basis of obtained results i.e.; sensory, physical and nutritional properties, sample 1 having cocoa butter 15 ml, unsalted butter 35 ml, cocoa powder 25 gm, stevia 25 gm, starch 25 gm, milk powder 25 gm, cranberry 2gm, agar-agar 5 ml and sample 2 having cocoa butter 15 ml, unsalted butter 40 ml, cocoa powder 25 gm, starch 50 gm, stevia 30 gm, milk powder 25 gm, cranberry 2gm, agar-agar 2 ml. The sensory analysis is done on the basis of 9-point hedonic scale. The overall acceptability score of sample 1 is 8 & sample 2 is 7 out of 9 points. The nutritive value of sample 1 chocolate were fat 13.08%, protein 13.47%, sugar 14.22, moisture content 9.93%, ash 3.48%, starch 11.47%. All the quality value of developed samples is noted. It was noted that the sensory, physical and nutritive qualities were improved due to incorporation of acceptable level of stevia at certain proportion. Stevia chocolate showed good quality characteristics on all the considered parameters. Results obtained were satisfactory & the developed chocolate is acceptable. Thus health benefits in the form of sugar free chocolate can tickle the taste buds of the consumers & influence them for consuming it for a healthy well-being. Hence, development & utilization of such functional foods will not only improve the nutritional status of the population but also helps those suffering from many diseases.
The human sweet taste receptor (T1R2) monomer—a member of the G-protein coupled receptor family that detects a wide variety of chemically and structurally diverse sweet tasting molecules, is known to pose a significant threat to human health. Protein that lack crystal structure is a challenge in structure-based protein design. This study focused on the interaction of the T1R2 monomer with rebaudioside A (Reb-A), a steviol glycoside with potential use as a natural sweetener using in-silico and biosensing methods. Herein, homology modelling, docking studies, and molecular dynamics simulations were applied to elucidate the interaction between Reb-A and the T1R2 monomer. In addition, the electrochemical sensing of the immobilised T1R2-Reb-A complex with zinc oxide nanoparticles (ZnONPs) and graphene oxide (GO) were assessed by testing the performance of multiwalled carbon nanotube (MWCNT) as an adsorbent experimentally. Results indicate a strong interaction between Reb-A and the T1R2 receptor, revealing the stabilizing interaction of the amino acids with the Reb-A by hydrogen bonds with the hydroxyl groups of the glucose moieties, along with a significant amount of hydrophobic interactions. Moreover, the presence of the MWCNT as an anchor confirms the adsorption strength of the T1R2-Reb-A complex onto the GO nanocomposite and supported with electrochemical measurements. Overall, this study could serve as a cornerstone in the development of electrochemical immunosensor for the detection of Reb-A, with applications in the food industry.
RESUMEN Stevia rebaudiana Bertoni (stevia) es una planta con potencial industrial, debido a que contiene glucósidos diterpenos, que le confieren propiedades edulcorantes. Además, la planta tiene propiedades medicinales y es usada como anticancerígena, antidepresiva, antiviral, antimicrobiana, y el control de la hipertensión y la obesidad, que son motivo de estudios recientes. Industrialmente, los glucósidos de stevia se usan para la preparación de alimentos y es un ingrediente de jugos, néctares, bebidas carbonatadas, pastelería, confitería, yogurt, chicles, entre otros. Sin embargo, el porcentaje bajo de germinación de las semillas limita la propagación de la planta por esta vía. Como una alternativa se realiza la propagación por métodos asexuales, a través de esquejes o brotes laterales; pero el número de propágulos es limitado y hay problemas de transmisión de enfermedades, lo que probablemente afecta la concentración de los compuestos de mayor interés. Por ello se realizan estudios usando nuevas estrategias de propagación de esta especie. En esta revisión se presenta una descripción de las características del cultivo de S. rebaudiana y del estado del arte del uso de herramientas biotecnológicas basadas en la micropropagación para la obtención de plántulas sanas de S. rebaudiana.
RESUMEN Stevia rebaudiana Bertoni (stevia) es una planta con potencial industrial, debido a que contiene glucósidos diterpenos, que le confieren propiedades edulcorantes. Además, la planta tiene propiedades medicinales y es usada como anticancerígena, antidepresiva, antiviral, antimicrobiana, y el control de la hipertensión y la obesidad, que son motivo de estudios recientes. Industrialmente, los glucósidos de stevia se usan para la preparación de alimentos y es un ingrediente de jugos, néctares, bebidas carbonatadas, pastelería, confitería, yogurt, chicles, entre otros. Sin embargo, el porcentaje bajo de germinación de las semillas limita la propagación de la planta por esta vía. Como una alternativa se realiza la propagación por métodos asexuales, a través de esquejes o brotes laterales; pero el número de propágulos es limitado y hay problemas de transmisión de enfermedades, lo que probablemente afecta la concentración de los compuestos de mayor interés. Por ello se realizan estudios usando nuevas estrategias de propagación de esta especie. En esta revisión se presenta una descripción de las características del cultivo de S. rebaudiana y del estado del arte del uso de herramientas biotecnológicas basadas en la micropropagación para la obtención de plántulas sanas de S. rebaudiana.
Purpose: The aim of the present study was to investigate antimicrobial activity of the various extracts of Stevia rebaudiana leaves. Method: Stevia rebaudiana Bertoni leaves were extracted in water, methanol, ethyl acetate and hexane and their antimicrobial activities were examined against few selected microorganisms including B. subtilis, S. aureus, M. luteus, S. marcenscens, P. aeruginosa, B. megaterium, E. coli, P. vulgaris, Yeast, A. niger and R. oligoporus using cup plate method. Results: Water extract of Stevia leaf showed activity against B. subtilis and S. aureus only. Methanol extract gave the highest zone of inhibition against P. aeruginosa whereas minimum zone of inhibition was found against S. aureus and yeast. B. megaterium and yeast were found to be highly susceptible towards ethyl acetate and hexane extracts, respectively whereas A. niger and B. subtilis were found to be least susceptible against ethyl acetate and hexane extracts, respectively. Hexane extract showed the highest activity against yeast among the tested microorganisms. Conclusion: The study confirms the possible antimicrobial potentiality of the leaf extract of Stevia rebaudiana.
Amaranthus hybridus, Brachiaria brizantha and Panicum maximum are wild cereal grains that have been consumed mainly in times of drought especially in the Manicaland Province, which is the worst-hit province in Zimbabwe whenever there are droughts. Methanolic extract solutions were prepared from sun-dried A. hybridus, B. brizantha and P. maximum grains. We studied the phenolic compound content and antioxidant properties including high-performance liquid chromatography, 1-diphenyl-2-pierylhydrazyl radical scavenging and reducing power. B. brizantha was found to contain the highest phenolic compound concentration of 3.180 ± 0.072 mgGA/100 mg, while A. hybridus was found to have the least phenolic compound concentration of 1.127 ± 0.133 mgGA/100 mg. The grains were found to contain caffeic acid, ferulic acid, p-coumaric acid, p-hydroxybenzoic acid and protocatechuic acid. P. maximum had the highest DPPH scavenging capacity and the highest reducing power as well. A. hybridus had the least reducing power and required 20.33 mg of sample equivalent per milliliter to reduce Fe3+ to Fe2+.
Antioxidant activity of methanolic extracts from root, leaf, stem and flower of Stevia rebaudiana (Bertoni) was investigated. The high amounts of Phenols, Flavonoids and Tannins were found in methanolic root and leaf extract among all parts, at the value of 16.75±0.35, 1.68±1.38, 12.56±5.78 and 11.04±3.16, 2.73±1.44, 12.98±2.17mg/g respectively. Total antioxidant activity of root, stem, leaves and flower was assessed by 2,2'-azino-bis-3-ethylbenzo-thi8azoline-6-sulfonic acid (ABTS) radical scavenging activity assay as well as 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Root extract showed highest (64.23±8.35 mM) TEAC 2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) radical scavenging activity; and Leaf, stem, flower showed 56.26±16.87 mM, 49.28±12.87 mM and 46.49±13.13 mM respectively. SOD, Catalase and peroxidase enzymatic assays were carried out to determine antioxidative potential of extracts, and the root extract was found to have highest activities 4.84±0.22, 8.6±0.45 and 2.24±0.05 respectively.Zones of inhibition at 500 mg ml-1 concentration are indicative of effective antibacterial activity of S.rebaudiana against B.subtilis NCIM 2708 and E.coli DM 4100.These results reveal that S. rebaudiana is an excellent antioxidant, and especially root and leaf show higher antioxidant effect and antibacterial activity.
A procedure has been outlined for plant regeneration and antimicrobial screening of a medicinal herb, Stevia rebaudiana Bertoni, through in vitro culture of nodal segments with axillary buds. Murashige and Skoog (MS) medium supplemented with 2.0 mg/L N 6 -benzyl amino purine and 1.13 mg/L indole-3-acetic acid in combination were found to be most effective in inducing bud break and growth, and in initiating multiple shoot proliferation at the rate of 39 microshoots per nodal explant after 30 d of culture. By repeated subculturing a high-frequency multiplication rate was established for production of elite lines of Stevia rebaudiana. Elongated shoots were transferred to rooting medium. MS medium supplemented with 2.0 mg/L indole-3-butyric acid was found to be best for rooting. In vitro and in vivo grown leaf extracts in different solvent system were screened for potential antimicrobial activity against medically important bacterial and fungal strains by agar well diffusion method. The chloroform and methanol extract exhibited a concentration dependent antibacterial and antifungal inhibition. Both in vitro and in vivo dried leaf extract showed similar antimicrobial activity. Therefore, commercial manufacture of active constituents from these improved elite lines would be useful and profitable.
Optimal conditions were developed for the HPLC-ESI-MS and supercritical fluid extraction of stevioside fromStevia rebaudiana leaves. In the HPLC-ESI-MS of this compound, the negative ion mode showed higher sensitivity than both UV and the positive
ion mode. In developing an alternative extraction method for stevioside using SFE, the effect of temperature, pressure, and
percentage of modifier was evaluated on the extraction yield. Although sufficient extractability was not obtained by pure
CO2 under any conditions of temperature and pressure, the addition of a modifier dramatically improved the extraction yield of
stevioside, making it comparable to organic solvent extraction. Among the modifiers evaluated, the mixture of methanol and
water showed greater extraction efficiency than the others. The extraction yield by CO2-methanol-water (80:16:4) was found to be 150% of conventional organic extraction. In addition to improving the extraction
yield, SFE obviously provided a higher purity of stevioside in the final extract.
The chemical composition of the hydrodistilled essential oils of Stevia rebaudiana Bertoni leaves, grown for the first time in an experimental field in Bangladesh, was analysed by GC–MS. Sixty two compounds representing 92.27 % of the total leaf oils were identified, of which α-cadinol (2.98 %), caryophyllene oxide (1.23 %), (-)-spathulenol (2.21 %) and β-Guaiene (0.32 %), were the major components. Thus, the monoterpenes and sesquiterpenes were the predominant constituents of the oils. The leaves contained some new essential oil compounds, such as ledene oxide-(ΙΙ), beta.-guaiene, geranyl vinyl ether, tricyclo [5.2.2.0 (1, 6)] undecan-3-ol, indole, aristolene epoxide, 1, 2, 3, 5, 6, 7, 8, 8a-octahydro-1, 4-dione and 2, 6, 6-trimethyl-2-cyclohexene-1, 4-dione identified for the first time.
Leaf extract of Stevia rebaudiana promotes effects on certain physiological systems such as the cardiovascular and renal and influences hypertension and hyperglycemia. Since these activities may be correlated with the presence of antioxidant compounds, leaf and callus extracts of Stevia rebaudiana were evaluated for their total phenols, flavonoids content and total antioxidant capacity. Total phenols and flavonoids were analyzed according to the Folin–Ciocalteu method and total antioxidant activity of water and methanolic extracts of stevia leaves and callus was assessed by ferric reducing/antioxidant power (FRAP) assay as well as 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The total phenolic compounds were found to be 25.18 mg/g for stevia leaves and 35.86 mg/g for callus on dry weight basis. The flavonoids content was found to be 21.73 and 31.99 mg/g in the leaf and callus, respectively. The total antioxidant activity was expressed as mg equivalent of gallic acid, ascorbic acid, BHA and trolox per gram on dry weight basis. Total antioxidant activity found was ranged from 9.66 to 38.24 mg and 11.03 to 36.40 mg equivalent to different standards in water and methanolic extract of stevia leaves, respectively. In case of stevia callus, it was found to be 9.44 to 37.36 mg for water extract and 10.14 to 34.37 mg equivalent to standards for methanolic extract. The concentrations required for 50% inhibition (IC50) of DPPH radicals were 11.04, 41.04 and 57.14 μg/mL for gallic acid, trolox and butylated hydroxyanisole (BHA), respectively. The percent inhibition of DPPH radical of various extracts of stevia leaves and callus found were ranged from 33.17% to 56.82%. The highest percent of inhibition was observed in methanolic extract of callus.
Purpose: The purpose of the study is to evaluate the antimicrobial and antitumor activities of Stevia rebaudiana (Asteraceae) leaf extracts. Methods: Four solvent extracts (ethyl acetate, acetone, chloroform and water) of Stevia rebaudiana leaves were investigated against Staphylococcus aureus , Salmonella typhi , Escherichia coli , Bacillus subtilis , Aeromonas hydrophila and Vibrio cholerae by using agar well diffusion method. Candida albicans , Cryptococcus neoformans , Trichophyton mentagrophytes and Epidermophyton species were used to test anti-yeast and antifungal activity. The cytotoxic effects of the extracts on Vero and HEp2 cells were assayed using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT]. Results: Among the four extracts tested, acetone extract had effective antibacterial potential, followed by ethyl acetate extract. The acetone extract showed greater activity against Gram-positive than against Gram-negative organisms. All the extracts were active against Epidermophyton species and Candida albicans . The 1:8 dilution of the acetone extract was non-toxic to normal cells and also had both anticancer and anti-proliferative activities against cancerous cells. Conclusion: The study confirms the antimicrobial and antitumor activities of Stevia rebaudiana leaves extracted using various solvents, and is therefore, a potential drug that requires further studies and development.
Stevia plants are a good source of carbohydrates (61.93% d.w.), protein (11.41% d.w.), crude fiber (15.52% d.w.), minerals (K, 21.15; Ca, 17.7; Na, 14.93 and Mg, 3.26 mg/100 g d.w. and Cu, 0.73; Mn, 2.89; Fe, 5.89 and Zn, 1.26 mg/100 g d.w.) also essential amino acids were found in amounts higher than those recommended by FAO and WHO for adults as well as non-essential amino acids. Stevioside was extracted and purified from the dried Stevia leaves by three methods. The first one, extraction by hot water (65°C) at different ratios of leaves to water (1:15 -1:75). The optimum ratio was 1:35 in which the maximum stevioside content was obtained (7.53%), recovery of stevioside was 80.21% and purity related to depigmentation was 97.56%. The second method, extraction by methanol at ratio 4:1 methanol/leaves and purification, recovery of stevioside was 94.90% and purity was 81.53%. The third method,extraction by mixture of methanol/water (4:1) and purification, recovery of stevioside and purity were 92.34 and 79.81%, respectively. Physical and chemical characteristics of the extracted stevioside were studied. Stevioside extractions were analyzed by HPLC in which the highest amount of stevioside (23.20%) was obtained in methanol extract. Also, organolyptic characteristics of extractions indicate that this sweetener has been applied as substitutes for sucrose in different drinks and baking products.
In the present study, in order to maximize the yield of total carbohydrates from Stevia rebaudiana Bertoni, Stevia LUYU-131 was used as test material, and response surface methodology (RSM) was employed to optimize the ultrasound-assisted extraction condition. The results indicated the optimal extraction conditions were an extraction temperature of 68°C, a sonic power of 60W and an extraction time of 32min. Using the ultrasound-assisted extraction, the yield of extracts increased by a factor of 1.5 at the lower extraction temperature (68°C) and the extraction time (32min) substantially shortened compared with that of classical extraction. The components analysis of crude extracts revealed that the relative amount of rebaudioside A increased in the ultrasound-assisted extracts as compared with extracts obtained by classical process, and the ultrasound-assisted extracts had better quality.
Essential oil (EO), water extract (WE), and methanol–water (MWE) (50/50 v:v) were prepared from Stevia rebaudiana Bertoni leaves. Their chemicals compounds, antioxidant, anti-inflammation and antimicrobial activities were evaluated. The EO was analyzed by gas chromatography/mass spectrometry. The WE, and MWE compounds were identified by RP-HPLC. In EO, carvacrol, caryophyllene, caryophyllene oxide, spathulenol, cardinol, α-pinene, limonene, isopinocarveol and ibuprofen were identified as major compounds. Furthermore, in the WE and MWE, the major compounds were, quercetin dihydrate, protocatechuic acid and quercetin glucosyl. These results show that S. rebaudiana EO and extracts possess high antioxidant, anti-inflammation and antimicrobial properties. The antimicrobial and antifungal activities of the extracts (EO, WE, MWE) were tested on Staphylococcus aureus; Bacillus subtillis; Escherichia coli; Pseudomonas aeruginosa; Aspergillus niger and Candida albicans, the lowest activity was founded on the EO extract.
A promising method of micropropagation of Stevia rebaudiana Bertoni has been developed with an aim to increase the biomass, survivability of the plantlets and stevioside production, using chlorocholine chloride (CCC). Microshoots transferred to the MS medium containing different combinations CCC and IBA were found to be most effective in terms of growth pattern, hardening ability of the plantlets and stevioside content, compared to MS medium containing either IBA or CCC. Among other combinations tested, MS medium supplemented with 3mg/l CCC and 3mg/l IBA was found most effective in inducing significant changes like reduced shoot length, increased number of roots, higher leaf size, increased biomass and chlorophyll retaining capacity, higher survival percentage and most importantly the elevated stevioside content. Collectively, the major observations of this research indicate that application of CCC in micropropagation of S. rebaudiana Bertoni is a promising approach and has commercial prospects.
METHODS for measuring antioxidants and appraising antioxidant activity appear to be of two general types. If the chemical nature of the antioxidant is known, one may strive for a test specific for the compound or group of interest; for example, the nitroprusside test for sulphydryl groups. Alternatively one may observe the inhibition of some natural oxidative process such as the β-oxidation of fats, as a function of the added antioxidant.
A very rapid and efficient regeneration method has been established using mature expiants ofStevia rebaudiana Bert. Adventitious shoots were induced from nodal expiants of field-grown plants on four basal media supplemented with various
combinations of auxins and cytokinins. The best performance (23.4 ± 2.1 shoots per expiant) was obtained on a Murashige and
Skoog (MS) medium containing 2 mg L-1 IAA and 0.5 mg L-1 kinetin. Roots were then produced when thesein vitro- regenerated shoots were transferred to an MS medium supplemented with 3% sucrose and 2 mg L-1 IBA. When acclimatized to soil, the rooted plants had a 98.4% survival rate. Following transplantation in the field, stevioside
contents were similar between the regenerated plants (10.68 mg g-1 dry weight) and the mother plants (12.01 mg g-1 dw).
This study was designed to examine the in vitro antioxidant activities of the methanol extracts of four Helichrysum species (Helichrysum noeanum Boiss., H. chionophilum Boiss. & Bal., H. plicatum DC. subsp. plicatum, H. arenarium (L.) Moench. subsp. aucheri (Boiss.) Davis & Kuphicha). The extracts were screened for their possible antioxidant activitiy by two complementary test systems, namely DPPH free radical-scavenging and β-carotene/linoleic acid systems. In the first case, non-polar subfractions of the methanol extracts of Helichrysum species studied did not show any antioxidant activity, while the most active one was H. chionophilum (IC50 =40.5 μg/ml) among the polar subfractions. In the β-carotene/linoleic acid test system, inhibition rates of the oxidation of linoleic acid of H. noeanum and H. arenarium were very close to each other. The inhibition rate of the synthetic antioxidant BHT was determined to be 96%. Since the polar extracts of Helichrysum species dealt with here exhibited interesting antioxidant activities when compared to BHT, we believe that it would be useful to take the results into consideration as an alternative for food processing industries.
Stevioside is a natural sweetener extracted from leaves of Stevia rebaudiana Bertoni, which is commercially produced by conventional (chemical/physical) processes. This article gives an overview of the stevioside structure, various analysis technique, new technologies required and the advances achieved in recent years. An enzymatic process is established, by which the maximum efficacy and benefit of the process can be achieved. The efficiency of the enzymatic process is quite comparable to that of other physical and chemical methods. Finally, we believe that in the future, the enzyme-based extraction will ensure more cost-effective availability of stevioside, thus assisting in the development of more food-based applications.
The use of (1)H NMR spectroscopy for the characterization of Stevia rebaudiana extracts is presented. The developed method allows qualitative and quantitative determination of the major steviol glycosides in purified extracts and fractions obtained from various stages of the purification process. Moreover, it proved to be a powerful tool to differentiate between glycosides which are naturally occurring in the stevia plant and artifacts formed in the course of the manufacturing process. Identification of steviol glycosides was achieved by the use of 2D NMR techniques, whereas quantification is based on qHNMR using anthracene as internal standard. The solvent mixture pyridine-d(5)-DMSO-d(6) (6:1) enabled satisfactory separation of the signals to be integrated. Validation of the method was performed in terms of specificity, precision, accuracy, linearity, robustness, and stability. Quantitative results were compared to those obtained with the JECFA HPLC-UV method and were found to be in reasonable agreement. NMR analysis does not rely on the use of reference compounds and enables significantly faster analysis compared to HPLC-UV. Thus, NMR represents a feasible alternative to HPLC-based methods for the quality control of Stevia rebaudiana extracts.
In existing processes, extraction and refining of glycoside based sweeteners from stevia leaves involves many process steps including extraction by organic solvents. The purpose of the present study was to develop a process of extraction and refining of sweeteners with reduced number of unit operations and minimization and/or elimination of chemical usage including organic solvents. It was found that water was very effective for extracting glycosides at selected pH and temperatures. It was also shown that a multi-stage membrane process was successfully able to concentrate the glycoside sweeteners. Based on the preliminary results, it appears that bitter-tasting components were washed out from the sweetener concentrate in the nanofiltration process. This work also has demonstrated that a membrane-based separation process for refining glycoside-based sweeteners could be viable and needs to be investigated further. Yes
The aim of this study was to assess the in vitro potential of ethanolic leaf extract of Stevia rebaudiana as a natural antioxidant. The DPPH activity of the extract (20, 40, 50, 100 and 200 microg/ml) was increased in a dose dependent manner, which was found in the range of 36.93-68.76% as compared to ascorbic acid 64.26-82.58%. The IC(50) values of ethanolic extract and ascorbic acid in DPPH radical scavenging assay were obtained to be 93.46 and 26.75 microg/ml, respectively. The ethanolic extract was also found to scavenge the superoxide generated by EDTA/NBT system. Measurement of total phenolic content of the ethanolic extract of S. rebaudiana was achieved using Folin-Ciocalteau reagent containing 61.50 mg/g of phenolic content, which was found significantly higher when compared to reference standard gallic acid. The ethanolic extract also inhibited the hydroxyl radical, nitric oxide, superoxide anions with IC(50) values of 93.46, 132.05 and 81.08 microg/ml, respectively. However, the IC(50) values for the standard ascorbic acid were noted to be 26.75, 66.01 and 71.41 microg/ml respectively. The results obtained in this study clearly indicate that S. rebaudiana has a significant potential to use as a natural antioxidant agent.
Stevioside and rebaudioside-A are major low-calorie diterpene steviol glycosides in the leaves of Stevia rebaudiana. They are widely used as natural sweeteners for diabetic patients, but the long extraction procedures required and the optimisation of product yield present challenging problems.
To develop a rapid and effective methodology for the extraction of stevioside and rebaudioside-A from S. rebaudiana leaves and to compare yields using different extraction techniques.
Dried and powdered leaves of S. rebaudiana were extracted by conventional, ultrasound and microwave-assisted extraction techniques using methanol, ethanol and water as single solvents as well as in binary mixtures. Conventional cold extraction was performed at 25 degrees C for 12 h while ultrasound extraction was carried out at temperature of 35 +/- 5 degrees C for 30 min. Microwave-assisted extraction (MAE) was carried out at a power level of 80 W for 1 min at 50 degrees C.
MAE yielded 8.64 and 2.34% of stevioside and rebaudioside-A, respectively, while conventional and ultrasound techniques yielded 6.54 and 1.20%, and 4.20 and 1.98% of stevioside and rebaudioside-A, respectively.
A rapid and efficient method has been developed for the extraction of stevioside and rebaudioside-A in optimum yields using MAE procedure. This method has the advantage of rapid extraction and fast screening of a large number of S. rebaudiana samples for assessment of planting material. MAE saves considerable time, energy and has implications in the quality assessment of stevioside and rebaudioside-A prior to their industrial production from the leaves of S. rebaudiana.
Thirteen essential oils were examined for their antioxidant activity using three different assay systems. Jasmine, parsley seed, rose, and ylang-ylang oils inhibited hexanal oxidation by over 95% after 40 days at a level of 500 microg/mL in the aldehyde/carboxylic acid assay. Scavenging abilities of the oils for the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical ranged from 39% for angelica seed oil to 90% for jasmine oil at a level of 200 microg/mL. The greatest inhibitory activity toward malonaldehyde (MA) formation from squalene upon UV-irradiation was obtained from parsley seed oil (inhibitory effect, 67%), followed by rose oil (46%), and celery seed oil (23%) at the level of 500 microg/mL. The main compounds of oils showing high antioxidant activity were limonene (composition, 74.6%) in celery seed, benzyl acetate (22.9%) in jasmine, alpha-pinene (33.7%) in juniper berry, myristicin (44%) in parsley seed, patchouli alcohol (28.8%) in patchouli, citronellol (34.2%) in rose, and germacrene (19.1%) in ylang-ylang.
http://dx.doi.org/10.1021 /jf062959x Cite this article as: Manoharan Ramya Studies on biochemical and medicinal properties of Stevia rebaudiana grown In vitro
- A Wei
- T Shibamoto
Wei A and Shibamoto T. Antioxidant activities and volatile
constituents of various essential oils. Journal of Agricultural and
Food Chemistry 2007; 55: 1737-1742. http://dx.doi.org/10.1021
/jf062959x
Cite this article as:
Manoharan Ramya, Sivasangari Manogaran, Kok Joey, Teh Wooi
keong, Sarveisan Katherasan. Studies on biochemical and medicinal
properties of Stevia rebaudiana grown In vitro. Int. J. Res. Ayurveda
Pharm. 2014;5(2):169-174 http://dx.doi.org/10.7897/2277-4343.05234
Chromatographic determination of stevioside in leaf parts of in vitro and in vivo regenerated plants of Stevia rebaudiana
- H Kaur
Kaur H. Chromatographic determination of stevioside in leaf parts
of in vitro and in vivo regenerated plants of Stevia rebaudiana.
International Journal of Natural Products Research 2011; 1(4): 44-48.
Comparative antimicrobial potential of different extracts of leaves of Stevia rebaudiana Bert
- K Das
- R Dang
- N Gupta
Das K, Dang R and Gupta N. Comparative antimicrobial potential
of different extracts of leaves of Stevia rebaudiana Bert.
International Journal of Natural and Engineering Sciences 2008;
3(1): 65-68.