- First Derivative of the Stevia rebaudiana Glycoside Steviolbioside Containing Thiazolylhydrazone Moieties
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A derivative of the Stevia rebaudiana glycoside steviolbioside in which two molecules containing thiazolylhydrazone groups on C-16 atoms were connected through a polymethylene linker to their carboxylic functionalities was synthesized for the first time.
- Sharipova,Garifullin,Andreeva,Strobykina, I. Yu.,Kataev
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- Quantitation of sweet steviol glycosides by means of a HILIC-MS/MS-SIDA approach
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Meeting the rising consumer demand for natural food ingredients, steviol glycosides, the sweet principle of Stevia rebaudiana Bertoni (Bertoni), have recently been approved as food additives in the European Union. As regulatory constraints require sensitive methods to analyze the sweet-tasting steviol glycosides in foods and beverages, a HILIC-MS/MS method was developed enabling the accurate and reliable quantitation of the major steviol glycosides stevioside, rebaudiosides A-F, steviolbioside, rubusoside, and dulcoside A by using the corresponding deuterated 16,17-dihydrosteviol glycosides as suitable internal standards. This quantitation not only enables the analysis of the individual steviol glycosides in foods and beverages but also can support the optimization of breeding and postharvest downstream processing of Stevia plants to produce preferentially sweet and least bitter tasting Stevia extracts.
- Well, Caroline,Frank, Oliver,Hofmann, Thomas
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- Production and physicochemical assessment of new stevia amino acid sweeteners from the natural stevioside
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New stevia amino acid sweeteners, stevia glycine ethyl ester (ST-GL) and stevia l-alanine methyl ester (ST-GL), were synthesised and characterised by IR, NMR (1H NMR and 13C NMR) and elemental analysis. The purity of the new sweeteners was determined by HPLC and their sensory properties were evaluated relative to sucrose in an aqueous system. Furthermore, the stevia derivatives (ST-GL and ST-AL) were evaluated for their acute toxicity, melting point, solubility and heat stability. The novel sweeteners were stable in acidic, neutral or basic aqueous solutions maintained at 100 °C for 2 h. The sweetness intensity rate of the novel sweeteners was higher than sucrose. Stevia amino acid (ST-GL and ST-AL) solutions had a clean sweetness taste without bitterness when compared to stevioside. The novel sweeteners can be utilised as non-caloric sweeteners in the production of low-calorie food.
- Khattab, Sherine N.,Massoud, Mona I.,Jad, Yahya El-Sayed,Bekhit, Adnan A.,El-Faham, Ayman
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- Synthesis and antituberculosis activity of derivatives of Stevia rebaudiana glycoside steviolbioside and diterpenoid isosteviol containing hydrazone, hydrazide, and pyridinoyl moieties
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Conjugates of the antituberculosis drug isoniazid (isonicotinyl hydrazine) and isomeric hydrazides of nicotinic and α-picolinic acid with glycoside steviolbioside from the Stevia rebaudiana plant and the product of its acid hydrolysis, diterpenoid isosteviol, were synthesized. In addition, isosteviol hydrazide and hydrazone derivatives as well as conjugates containing two isosteviol moieties joined by a dihydrazide linker were obtained. The parental compounds and their synthetic derivatives were found to inhibit the in vitro growth of Mycobacterium tuberculosis (H37RV). The measured minimal concentrations of stevioside and steviolbioside, at which the growth of M. tuberculosis was inhibited by 100% (MIC), were 7.5 and 3.8 μg/ml, respectively. MIC values for steviolbioside and isosteviol conjugates with hydrazides of pyridine carbonic acid were within the ranges of 5-10 and 10-20 μg/ml, respectively. The maximal inhibitory effect against M. tuberculosis was shown by the isosteviol conjugates with adipic acid dihydrazide (MIC 1.7 and 3.1 μg/ml). Antituberculosis activities of the tested compounds were higher than the activity of antituberculosis drug Pyrizanamide (MIC 20 μg/ml) but lower than that of antituberculosis drug isoniazid (MIC 0.02-0.04 μg/ml). Pleiades Publishing, Ltd., 2011.
- Kataev,Strobykina,Andreeva,Garifullin,Sharipova,Mironov,Chestnova
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- Enzymic production of sweet stevioside derivatives: transglucosylation by glucosidases.
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For the purpose of improving sweetness and a further study on the structure-sweetness relationship of steviol glycosides, transglycosylation of stevioside by a variety of commercial glucosidases was investigated. It was revealed that two alpha-glucosidases gave glucosylated products. Transglucosylation of stevioside by Pullulanase and pullulan exclusively afforded three products, 13-O-[beta-maltotriosyl-(1----2)-beta-D-glucosyl]-19-O-beta-D-g luc osyl- steviol (1), 13-O-[beta-maltosyl-(1----2)-beta-D-glucosyl]-19-O-beta-D-glucosyl- steviol (2) and 13-O-beta-sophorosyl-19-O-beta-maltotriosyl-steviol (3). All of these products have already been obtained by trans-alpha-1,4-glucosylation of stevioside by the cyclodextrin glucanotransferase starch system, and 1 and 2 have been proven to be tasty and potent sweeteners. Transglucosylation of stevioside by Biozyme L and maltose afforded three new products, 4, 5 and 6, the structures of these compounds being elucidated as 13-O-beta-sophorosyl-19-O-beta-isomaltosyl-steviol (4), 13-O-[beta-isomaltosyl(1----2)-beta-D-glucosyl]-19-O-beta-D-glucosyl- steviol (5) and 13-O-[beta-nigerosyl-(1----2)-beta-D-glucosyl]-19-O-beta-D- glucosyl-steviol (6). A significantly high quality of taste was evaluated for 4.
- Lobov,Kasai,Ohtani,Tanaka,Yamasaki
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- Human psychometric and taste receptor responses to steviol glycosides
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Steviol glycosides, the sweet principle of Stevia Rebaudiana (Bertoni) Bertoni, have recently been approved as a food additive in the EU. The herbal non-nutritive high-potency sweeteners perfectly meet the rising consumer demand for natural food ingredients in Europe. We have characterized the organoleptic properties of the most common steviol glycosides by an experimental approach combining human sensory studies and cell-based functional taste receptor expression assays. On the basis of their potency to elicit sweet and bitter taste sensations, we identified glycone chain length, pyranose substitution, and the C16 double bond as the structural features giving distinction to the gustatory profile of steviol glycosides. A comprehensive screening of 25 human bitter taste receptors revealed that two receptors, hTAS2R4 and hTAS2R14, mediate the bitter off-taste of steviol glycosides. For some test substances, e.g., stevioside, we observed a decline in sweet intensity at supra-maximum concentrations. This effect did not arise from allosteric modulation of the hTAS1R2/R3 sweet taste receptor but might be explained by intramolecular cross-modal suppression between the sweet and bitter taste component of steviol glycosides. These results might contribute to the production of preferentially sweet and least bitter tasting Stevia extracts by an optimization of breeding and postharvest downstream processing.
- Hellfritsch, Caroline,Brockhoff, Anne,Staehler, Frauke,Meyerhof, Wolfgang,Hofmann, Thomas
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- Synthesis of thiazolylhydrazones of the Stevia rebaudiana glycoside steviolbioside
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Thiazolylhydrazones of the Stevia rebaudiana glycoside steviolbioside were synthesized for the first time.
- Sharipova,Garifullin,Andreeva,Strobykina, I. Yu.,Kataev
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- Functionalization of the double bond in the glycoside of the Stevia rebaudiana plant steviolbioside, as a way to macrocyclic glycosides
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The C16=C17 bond in the glycoside steviolbioside from the plant Stevia rebaudiana was oxidized for the first time. Ketone, thiosemicarbazone, and oxime of steviolbioside with a heptaacetylated sophorosyl fragment, as well as binuclea
- Sharipova,Garifullin,Andreeva,Strobykina,Bazanova,Kataev
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- INHIBITORS OF ANTIBIOTIC RESISTANCE MEDIATED BY ARN T
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The present invention relates to diterpene compounds of general formula (I) capable of contrasting the antibiotic-resistance mediated by the ArnT enzyme, to their use as a medicament, in particular for use as an adjuvant of an antibiotic therapy in the treatment of antibiotic-resistant bacterial infections. The invention relates also to associations of one or more of the compounds of formula (I) with at least another active ingredient, in particular an antibacterial agent and/or an antibiotic, and compositions comprising one or more compounds of formula (I) or the association according to the present invention and at least one pharmaceutically acceptable excipient and/or carrier as well as to products, in particular medical devices, comprising at least a compound, an association or a composition according to the present invention. Moreover, the invention relates to the use of compounds of formula (I) to sensitize a bacterium to an antibacterial agent or an antibiotic, for example, colistin (polymyxin E) or polymyxin B and to an in vivo or in vitro method for sensitizing a bacterium to an antibacterial agent or an antibiotic comprising the exposure of said bacterium to one or more compounds of formula (I) together with colistin.
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Page/Page column 27-28
(2021/01/29)
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- NATURAL AND SYNTHETIC DITERPENE GLYCOSIDES, COMPOSITIONS AND METHODS
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Novel diterpene glycosides isolated from Stevia extract as well as diterpene glycosides that are synthetically prepared are provided herein. Compositions and consumables comprising the novel diterpene glycosides are also provided herein. Methods of enhancing the sweetness and/or flavor of consumables using the novel diterpene glycosides, methods of preparing compositions and consumables comprising the novel diterpene glycosides, methods of purifying the novel diterpene glycosides and methods of synthesizing the diterpene glycosides are also provided.
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Page/Page column 99; 111-112; 121-122
(2019/08/12)
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- Synthesis and Antimicrobial Activity of Glucuronosyl Derivatives of Steviolbioside from Stevia rebaudiana
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Glucuronosyl derivatives of the glycoside steviolbioside from Stevia rebaudiana were synthesized for the first time. Steviolbioside exhibited selective bacteriostatic and bactericidal activity against S. aureus ATCC 209p with minimum inhibitory concentration (MIC) of 62.5 μg/mL, which corresponded to the activity of the antibiotic chloramphenicol.
- Sharipova,Andreeva,Strobykina, I. Yu.,Voloshina,Strobykina,Kataev
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p. 1107 - 1111
(2017/11/27)
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- Validation of an HPLC method for direct measurement of steviol equivalents in foods
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Steviol glycosides are intense natural sweeteners used in foods and beverages. Their acceptable daily intake, expressed as steviol equivalents, is set at 0-4 mg/kg body weight. We report the development and validation of a RP-HPLC method with fluorometric detection of derivatized isosteviol, formed by acid hydrolysis of steviol glycosides. Dihydroisosteviol was used as an internal standard. Using this method, the amount of steviol equivalents in commercial steviol glycoside mixtures and different foods can be directly quantified. The method was successfully tested on strawberry jam, low-fat milk, soft drink, yogurt and a commercial mixture of steviol glycosides. Calibration curves were linear between 0.01 and 1.61 mM steviol equivalents, with a quantification limit of 0.2 nmol. The % RSD of intra-day precision varied between 0.4% and 4%, whereas inter-day precision varied between 0.4% and 5%, for high and medium concentrations, and between 3% and 8% for low concentrations. Accuracy of the analysis varied between 99% and 115%.
- Bartholomees, Uria,Struyf, Tom,Lauwers, Olivier,Ceunen, Stijn,Geuns, Jan M.C.
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p. 270 - 275
(2015/06/08)
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- Enzymatic preparation of a natural sweetener rubusoside from specific hydrolysis of stevioside with β-galactosidase from Aspergillus sp.
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Rubusoside is a precious bioactive sweetener which mainly exists in Chinese sweet tea plant (Rubus suavissimus S. Lee), while stevioside is an abundant natural sweetener with bitter aftertaste. In this work, a β-galactosidase from Aspergillus sp. presented specific hydrolytic activity on β-1,2 glucosidic linkage of stevioside, and converting stevioside to rubusoside. The hydrolytic activity was weak on the natural stevioside analogs, which makes the process a promising approach to produce rubusoside and utilize stevioside. The highest steviosides conversion was 98.3%, accompanying with a rubusoside yield of 91.4%.
- Wan, Hui-Da,Tao, Guan-Jun,Kim, Doman,Xia, Yong-Mei
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experimental part
p. 12 - 17
(2012/10/08)
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- TOTAL SYNTHESIS OF STEVIOSIDE
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Steviol 2 was transformed into stevioside 1 by applying the stereoselective methods of glycosidation.
- Ogawa, Tomoya,Nozaki, Michio,Matsui, Masanao
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p. 2641 - 2648
(2007/10/02)
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