الفهرس 
Title : Development of a standardized extract for ameliorating metabolic syndrome from the natural sweetener stevia rebaudiana (BERT.)
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Abstract
Stevia rebaudiana Bertoni. (Family Asteraceae) has gained commercial importance as a natural no calorie sweetener, owing to its content of steviol glycosides (stevioside and rebaudiosides) (SVGs). Besides its sweetness properties, SVGs are effective as hypoglycemic and antioxidant.Total Aqeoues Extract (TAqE) and Total Ethanolic extract (TEE) of the leaves were fractionated on Di-aion HP-20 to yield steviosides rich fraction (SRF) and flavonoids rich fraction (FRF), respectively. Total phenolic content was found to be 127.96 ± 0.51 æg as gallic acid equivalent/100gm dry powder,while total flavonoid content was 50.55 ± 5.7 æg/mg extract.UPLC-HRMS profiling of the secondary metabolites revealed tentative identification of 29 compounds. SRF has the highest inhibitory action on Ü-amylase and Ü-glucosidase with IC50 values of 203.8 ±1.3 and 118.5±1.2, respectively and the highest inhibitory action on lipase with IC50 value of 60.5 ±1.5. Of the extracts tested, both TEE and FRF showed potent antioxidant activities (IC50 values of 403.5±16 æg/ml and 301.61±48.41 æg/ml, respectively.DNA fingerprinting revealed that 3 cultivars tested, Canadian {u2260}Nubareya and Canadian {u2260}Ismelia are more genetically related.Two flavonoids ;quercetin-3-O-rhamnoside and Apigenin-7-O-rhamnopyranoside were isolated from FRF, and two SVGs; stevioside and rebaudioside A were isolated from SRF. Jhanol and Ý-Sitosterol were isolated from the acetone fraction of Diaion Hp-20.Biologically guided study of the leaf extracts revealed the prevalence of the Aqoues extract over the Ethanolic in controlling hyperglycemia and hyperlipidemia associated with metabolic syndrome