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Josef Caslavský - One of the best experts on this subject based on the ideXlab platform.
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comparison of two different solvents employed for pressurised fluid extraction of Stevioside from stevia rebaudiana methanol versus water
Analytical and Bioanalytical Chemistry, 2007Co-Authors: Elena Varaďova Ostra, Pavel Karásek, Karolínka Benešová, Pavla Kotlaříková, Michal Roth, Josef CaslavskýAbstract:Pressurised fluid extraction using water or metha- nol was employed for the extraction of Stevioside from Stevia rebaudiana Bertoni. The extraction method was optimised in terms of temperature and duration of the static or the dynamic step. Extracts were analysed by liquid chromatography followed by UV and mass-spectrometric (MS) detections. Thermal degradation of Stevioside was the same in both solvents within the range 70-160 °C. Methanol showed better extraction ability for isolation of Stevioside from Stevia rebaudiana leaves than water within the range 110-160 °C. However, water represents the green alternative to methanol. The limit of detection of Stevioside in the extract analysed was 30 ng for UV detection and 2 ng for MS detection.
Kjeld Hermansen - One of the best experts on this subject based on the ideXlab platform.
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antihyperglycemic effects of Stevioside in type 2 diabetic subjects
Metabolism-clinical and Experimental, 2004Co-Authors: Soren Gregersen, Per Bendix Jeppesen, Jens J Holst, Kjeld HermansenAbstract:Stevioside is present in the plant Stevia rebaudiana Bertoni (SrB). Extracts of SrB have been used for the treatment of diabetes in, for example, Brazil, although a positive effect on glucose metabolism has not been unequivocally demonstrated. We studied the acute effects of Stevioside in type 2 diabetic patients. We hypothesize that supplementation with Stevioside to a test meal causes a reduction in postprandial blood glucose. Twelve type 2 diabetic patients were included in an acute, paired cross-over study. A standard test meal was supplemented with eithe r1go fStevioside o r1go fmaize starch (control). Blood samples were drawn at 30 minutes before and for 240 minutes after ingestion of the test meal. Compared to control, Stevioside reduced the incremental area under the glucose response curve by 18% (P .013). The insulinogenic index (AUCi,insulin/AUCi,glucose) was increased by approximately 40% by Stevioside compared to control (P < .001). Stevioside tended to decrease glucagon levels, while it did not significantly alter the area under the insulin, glucagon-like peptide 1, and glucose-dependent insulinotropic polypeptide curves. In conclusion, Stevioside reduces postprandial blood glucose levels in type 2 diabetic patients, indicating beneficial effects on the glucose metabolism. Stevioside may be advantageous in the treatment of type 2 diabetes.
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antihyperglycemic and blood pressure reducing effects of Stevioside in the diabetic goto kakizaki rat
Metabolism-clinical and Experimental, 2003Co-Authors: Per Bendix Jeppesen, S Gregersen, S E D Rolfsen, M Jepsen, Michele Colombo, Andreas Agger, Jianzhong Xiao, Mogens Kruhoffer, Torben F Orntoft, Kjeld HermansenAbstract:Stevioside, a glycoside present in the leaves of the plant, Stevia rebaudiana Bertoni (SrB), has acute insulinotropic effects in vitro. Its potential antihyperglycemic and blood pressure–lowering effects were examined in a long-term study in the type 2 diabetic Goto-Kakizaki (GK) rat. Rats were fed 0.025 g · kg−1 · d−1 of Stevioside (purity > 99.6%) for 6 weeks. An intra-arterial catheter was inserted into the rats after 5 weeks, and conscious rats were subjected to arterial glucose tolerance test (2.0 g · kg−1) during week 6. Stevioside had an antihyperglycemic effect (incremental area under the glucose response curve [IAUC]): 985 ± 20 (Stevioside) versus 1,575 ± 21 (control) mmol/L × 180 minutes, (P <.05), it enhanced the first-phase insulin response (IAUC: 343 ± 33 [Stevioside] v 136 ± 24 [control] μU/mL insulin × 30 minutes, P <.05) and concomitantly suppressed the glucagon levels (total AUC: 2,026 ± 234 [Stevioside] v 3,535 ± 282 [control] pg/mL × 180 minutes, P <.05). In addition, Stevioside caused a pronounced suppression of both the systolic (135 ± 2 v 153 ± 5 mm Hg; P <.001) and the diastolic blood pressure (74 ± 1 v 83 ± 1 mm Hg; P <.001). Bolus injections of Stevioside (0.025 g · kg−1) did not induce hypoglycemia. Stevioside augmented the insulin content in the β-cell line, INS-1. Stevioside may increase the insulin secretion, in part, by induction of genes involved in glycolysis. It may also improve the nutrient-sensing mechanisms, increase cytosolic long-chain fatty acyl-coenzyme A (CoA), and downregulate phosphodiesterase 1 (PDE1) estimated by the microarray gene chip technology. In conclusion, Stevioside enjoys a dual positive effect by acting as an antihyperglycemic and a blood pressure–lowering substance; effects that may have therapeutic potential in the treatment of type 2 diabetes and the metabolic syndrome. Copyright 2003, Elsevier Science (USA). All rights reserved.
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Stevioside induces antihyperglycaemic insulinotropic and glucagonostatic effects in vivo studies in the diabetic goto kakizaki gk rats
Phytomedicine, 2002Co-Authors: Per Bendix Jeppesen, S Gregersen, K K Alstrup, Kjeld HermansenAbstract:Summary Extracts of leaves from the plant Stevia rebaudiana Bertoni have been used in the traditional treatment of diabetes in Paraguay and Brazil. Recently, we demonstrated a direct insulinotropic effect in isolated mouse islets and the clonal beta cell line INS-1 of the glycoside Stevioside that is present in large quantity in these leaves. Type 2 diabetes is a chronic metabolic disorder that results from defects in both insulin and glucagon secretion as well as insulin action. In the present study we wanted to unravel if Stevioside in vivo exerts an antihyperglycaemic effect in a nonobese animal model of type 2 diabetes. An i.v. glucose tolerance test (IVGT) was carried out with and without Stevioside in the type 2 diabetic Goto-Kakizaki (GK) rat, as well as in the normal Wistar rat. Stevioside (0.2 g/kg BW) and D-glucose (2.0 g/kg BW) were administered as i.v. bolus injections in anaesthetized rats. Stevioside significantly suppressed the glucose response to the IVGT in GK rats (incremental area under the curve (IAUC): 648 ± 50 (Stevioside) vs 958 ± 85 mM × 120 min (control); P
Josef Čáslavský - One of the best experts on this subject based on the ideXlab platform.
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Comparison of two different solvents employed for pressurised fluid extraction of Stevioside from Stevia rebaudiana: Methanol versus water
Analytical and Bioanalytical Chemistry, 2007Co-Authors: Jaroslav Pól, Elena Varaďová Ostrá, Pavel Karásek, Karolínka Benešová, Pavla Kotlaříková, Michal Roth, Josef ČáslavskýAbstract:Pressurised fluid extraction using water or methanol was employed for the extraction of Stevioside from Stevia rebaudiana Bertoni. The extraction method was optimised in terms of temperature and duration of the static or the dynamic step. Extracts were analysed by liquid chromatography followed by UV and mass-spectrometric (MS) detections. Thermal degradation of Stevioside was the same in both solvents within the range 70-160 degrees C. Methanol showed better extraction ability for isolation of Stevioside from Stevia rebaudiana leaves than water within the range 110-160 degrees C. However, water represents the green alternative to methanol. The limit of detection of Stevioside in the extract analysed was 30 ng for UV detection and 2 ng for MS detection.
Per Bendix Jeppesen - One of the best experts on this subject based on the ideXlab platform.
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antihyperglycemic effects of Stevioside in type 2 diabetic subjects
Metabolism-clinical and Experimental, 2004Co-Authors: Soren Gregersen, Per Bendix Jeppesen, Jens J Holst, Kjeld HermansenAbstract:Stevioside is present in the plant Stevia rebaudiana Bertoni (SrB). Extracts of SrB have been used for the treatment of diabetes in, for example, Brazil, although a positive effect on glucose metabolism has not been unequivocally demonstrated. We studied the acute effects of Stevioside in type 2 diabetic patients. We hypothesize that supplementation with Stevioside to a test meal causes a reduction in postprandial blood glucose. Twelve type 2 diabetic patients were included in an acute, paired cross-over study. A standard test meal was supplemented with eithe r1go fStevioside o r1go fmaize starch (control). Blood samples were drawn at 30 minutes before and for 240 minutes after ingestion of the test meal. Compared to control, Stevioside reduced the incremental area under the glucose response curve by 18% (P .013). The insulinogenic index (AUCi,insulin/AUCi,glucose) was increased by approximately 40% by Stevioside compared to control (P < .001). Stevioside tended to decrease glucagon levels, while it did not significantly alter the area under the insulin, glucagon-like peptide 1, and glucose-dependent insulinotropic polypeptide curves. In conclusion, Stevioside reduces postprandial blood glucose levels in type 2 diabetic patients, indicating beneficial effects on the glucose metabolism. Stevioside may be advantageous in the treatment of type 2 diabetes.
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antihyperglycemic and blood pressure reducing effects of Stevioside in the diabetic goto kakizaki rat
Metabolism-clinical and Experimental, 2003Co-Authors: Per Bendix Jeppesen, S Gregersen, S E D Rolfsen, M Jepsen, Michele Colombo, Andreas Agger, Jianzhong Xiao, Mogens Kruhoffer, Torben F Orntoft, Kjeld HermansenAbstract:Stevioside, a glycoside present in the leaves of the plant, Stevia rebaudiana Bertoni (SrB), has acute insulinotropic effects in vitro. Its potential antihyperglycemic and blood pressure–lowering effects were examined in a long-term study in the type 2 diabetic Goto-Kakizaki (GK) rat. Rats were fed 0.025 g · kg−1 · d−1 of Stevioside (purity > 99.6%) for 6 weeks. An intra-arterial catheter was inserted into the rats after 5 weeks, and conscious rats were subjected to arterial glucose tolerance test (2.0 g · kg−1) during week 6. Stevioside had an antihyperglycemic effect (incremental area under the glucose response curve [IAUC]): 985 ± 20 (Stevioside) versus 1,575 ± 21 (control) mmol/L × 180 minutes, (P <.05), it enhanced the first-phase insulin response (IAUC: 343 ± 33 [Stevioside] v 136 ± 24 [control] μU/mL insulin × 30 minutes, P <.05) and concomitantly suppressed the glucagon levels (total AUC: 2,026 ± 234 [Stevioside] v 3,535 ± 282 [control] pg/mL × 180 minutes, P <.05). In addition, Stevioside caused a pronounced suppression of both the systolic (135 ± 2 v 153 ± 5 mm Hg; P <.001) and the diastolic blood pressure (74 ± 1 v 83 ± 1 mm Hg; P <.001). Bolus injections of Stevioside (0.025 g · kg−1) did not induce hypoglycemia. Stevioside augmented the insulin content in the β-cell line, INS-1. Stevioside may increase the insulin secretion, in part, by induction of genes involved in glycolysis. It may also improve the nutrient-sensing mechanisms, increase cytosolic long-chain fatty acyl-coenzyme A (CoA), and downregulate phosphodiesterase 1 (PDE1) estimated by the microarray gene chip technology. In conclusion, Stevioside enjoys a dual positive effect by acting as an antihyperglycemic and a blood pressure–lowering substance; effects that may have therapeutic potential in the treatment of type 2 diabetes and the metabolic syndrome. Copyright 2003, Elsevier Science (USA). All rights reserved.
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Stevioside induces antihyperglycaemic insulinotropic and glucagonostatic effects in vivo studies in the diabetic goto kakizaki gk rats
Phytomedicine, 2002Co-Authors: Per Bendix Jeppesen, S Gregersen, K K Alstrup, Kjeld HermansenAbstract:Summary Extracts of leaves from the plant Stevia rebaudiana Bertoni have been used in the traditional treatment of diabetes in Paraguay and Brazil. Recently, we demonstrated a direct insulinotropic effect in isolated mouse islets and the clonal beta cell line INS-1 of the glycoside Stevioside that is present in large quantity in these leaves. Type 2 diabetes is a chronic metabolic disorder that results from defects in both insulin and glucagon secretion as well as insulin action. In the present study we wanted to unravel if Stevioside in vivo exerts an antihyperglycaemic effect in a nonobese animal model of type 2 diabetes. An i.v. glucose tolerance test (IVGT) was carried out with and without Stevioside in the type 2 diabetic Goto-Kakizaki (GK) rat, as well as in the normal Wistar rat. Stevioside (0.2 g/kg BW) and D-glucose (2.0 g/kg BW) were administered as i.v. bolus injections in anaesthetized rats. Stevioside significantly suppressed the glucose response to the IVGT in GK rats (incremental area under the curve (IAUC): 648 ± 50 (Stevioside) vs 958 ± 85 mM × 120 min (control); P
Pavel Karásek - One of the best experts on this subject based on the ideXlab platform.
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comparison of two different solvents employed for pressurised fluid extraction of Stevioside from stevia rebaudiana methanol versus water
Analytical and Bioanalytical Chemistry, 2007Co-Authors: Elena Varaďova Ostra, Pavel Karásek, Karolínka Benešová, Pavla Kotlaříková, Michal Roth, Josef CaslavskýAbstract:Pressurised fluid extraction using water or metha- nol was employed for the extraction of Stevioside from Stevia rebaudiana Bertoni. The extraction method was optimised in terms of temperature and duration of the static or the dynamic step. Extracts were analysed by liquid chromatography followed by UV and mass-spectrometric (MS) detections. Thermal degradation of Stevioside was the same in both solvents within the range 70-160 °C. Methanol showed better extraction ability for isolation of Stevioside from Stevia rebaudiana leaves than water within the range 110-160 °C. However, water represents the green alternative to methanol. The limit of detection of Stevioside in the extract analysed was 30 ng for UV detection and 2 ng for MS detection.
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Comparison of two different solvents employed for pressurised fluid extraction of Stevioside from Stevia rebaudiana: Methanol versus water
Analytical and Bioanalytical Chemistry, 2007Co-Authors: Jaroslav Pól, Elena Varaďová Ostrá, Pavel Karásek, Karolínka Benešová, Pavla Kotlaříková, Michal Roth, Josef ČáslavskýAbstract:Pressurised fluid extraction using water or methanol was employed for the extraction of Stevioside from Stevia rebaudiana Bertoni. The extraction method was optimised in terms of temperature and duration of the static or the dynamic step. Extracts were analysed by liquid chromatography followed by UV and mass-spectrometric (MS) detections. Thermal degradation of Stevioside was the same in both solvents within the range 70-160 degrees C. Methanol showed better extraction ability for isolation of Stevioside from Stevia rebaudiana leaves than water within the range 110-160 degrees C. However, water represents the green alternative to methanol. The limit of detection of Stevioside in the extract analysed was 30 ng for UV detection and 2 ng for MS detection.
