Ironstone Separations Inc.

MS, United States

Ironstone Separations Inc.

MS, United States
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Perera W.H.,Ironstone Separations Inc. | Avula B.,University of Mississippi | Khan I.A.,University of Mississippi | McChesney J.D.,Ironstone Separations Inc.
Rapid Communications in Mass Spectrometry | Year: 2017

Rationale: Steviol glycosides with an ent-kaurene core are being used in the Food Industry as non-caloric sweeteners. These compounds are chemically similar in terms of sugar types and sugar arrangements. In order to assign sugar positions, we describe herein the dissociation pattern for steviol glycosides under varying collision energies. Methods: Steviol glycosides (1 mg/mL, 2 μL) were automatically injected into the mass spectrometer by direct infusion using a 100-well tray autosampler. The mass spectrometric analysis was performed using a quadrupole time-of-flight (QTOF) tandem mass spectrometer (model #G6530A; Agilent Technologies, Palo Alto, CA, USA) equipped with an electrospray ionization (ESI) source with Jet Stream technology. Results: Dissociation of several natural and prepared steviol glycosides was carefully studied by ESI-QTOF-MS/MS using a range of collision energies: 10, 20, 30, 40, 50, 60, 70 and 80 eV. This procedure allowed us to establish the dissociation pattern for steviol glycosides, and thus the sugar arrangement in the branched oligosaccharide portion linked at position C-13 of steviol, and also infer the sugar arrangement at C-19. Conclusions: Those steviol glycosides with a monosaccharide or less hindered disaccharides at position C-19 are cleaved at low collision energy (10 eV) while highly hindered disaccharides and trisaccharides are cleaved at 40 eV. However, sugars attached at C-13 cleave at highest collision energies in the following order: the C-3 sugar, followed by the C-2 sugar and finally the sugar directly linked at C-13. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.


Abreu Miranda M.,University of Sao Paulo | Lemos M.,University of Sao Paulo | Alves Cowart K.,Ironstone Separations Inc. | Rodenburg D.,Ironstone Separations Inc. | And 4 more authors.
Journal of Ethnopharmacology | Year: 2015

Abstract Ethnopharmacological relevance Solanum cernuum Vell. (Solanaceae) is a Brazilian medicinal plant, traditionally known as "panaceia". Its folk name is probably due to its wide range of applications in traditional medicine including the treatment of ulcers. Aim of the study To evaluate the gastroprotective activities of the hydroethanolic extract (ESC) of S. cernuum and its major isolated compounds using in vivo gastric ulcer models. Material and methods The ESC extract was obtained by maceration followed by percolation of the dried and powdered leaves of S. cernuum in ethanol:water (7:3). The major compounds in the extract were isolated by applying various preparative chromatographic techniques. The gastroprotective activity was evaluated in mice using different gastric ulcer-induced models. The anti-Helicobacter pylori activity was performed using the agar-well diffusion and broth microdilution methods. Results The ESC extract showed gastroprotective effects in the assay of acute gastric ulcer-induced by HCl/EtOH, nonsteroidal anti-inflammatory drug, and acetic acid-induced chronic ulcer protocols. The results also demonstrated that the gastroprotection induced by ESC extract is related to the activity of nitric oxide and endogenous sulfhydryls, which are important gastroprotective factors. The ESC extract and the alkaloid cernumidine did not show activity against H. pylori in the concentrations tested. Conclusions The present study showed that the crude extract of S. cernuum possessed gastroprotective activity which corroborating the traditional use of this plant for the treatment of gastric ulcers. The isolated flavonoids, quercitrin and afzelin as well as the phenylpropanoid, isoferulic acid are suggested to be the compounds responsible for the gastroprotective activity of S. cernuum extract. © 2015 Published by Elsevier Ireland Ltd.


PubMed | Louisiana State University, St Jude Childrens Research Hospital and Ironstone Separations Inc.
Type: Journal Article | Journal: Journal of natural products | Year: 2016

Two new diterpene glycosides have been isolated from a commercial extract of the leaves of Stevia rebaudiana. Compound 1 was shown to be 13-[(2-O--d-glucopyranosyl-3-O--d-glucopyranosyl--d-xylopyranosyl)oxy]ent-kaur-16-en-19-oic acid -d-glucopyranosyl ester (rebaudioside R), while compound 2 was determined to be 13-[(2-O--d-glucopyranosyl--d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid 2-O--l-rhamnopyranosyl--d-glucopyranosyl ester (rebaudioside S). Six additional known compounds were identified, dulcoside B, 13-[(2-O--d-xylopyranosyl--d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid -d-glucopyranosyl ester, eugenol diglucoside, rebaudioside G, 13-[(2-O-6-deoxy--d-glucopyranosyl-3-O--d-glucopyranosyl--d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid -d-glucopyranosyl ester, and rebaudioside D (3), respectively. The structures of 1 and 2 were determined based on comprehensive 1D and 2D NMR (COSY, HSQC, and HMBC) studies. A high-quality crystal of compound 3 allowed confirmation of its structure by X-ray diffraction.


PubMed | University of Florida, University of Mississippi, National University of Pharmacy, St Jude Childrens Research Hospital and Ironstone Separations Inc.
Type: | Journal: Phytochemistry | Year: 2016

Two diterpene glycosides were isolated from a commercial Stevia rebaudiana leaf extract. One was found to be 13-[(2-O--d-glucopyranosyl-3-O--d-glucopyranosyl--d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid-(2-O--d-xylopyranosyl-3-O--d-glucopyranosyl- -d-glucopyranosyl) ester (rebaudioside T), whereas the other was determined to be 13-[(2-O--d-glucopyranosyl-3-O--d-glucopyranosyl--d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid-(6-O--l-arabinopyranosyl--d-glucopyranosyl) ester (rebaudioside U). In addition, five C-19 sugar free derivatives were prepared and identified as follows: 13-[(2-O--l-rhamnopyranosyl--d-glucopyranosyl)]oxy]kaur-16-en-19-oic acid (dulcoside A


PubMed | U.S. Army, University of Mississippi and Ironstone Separations Inc.
Type: | Journal: Malaria journal | Year: 2016

The clinical utility of primaquine (PQ), used as a racemic mixture of two enantiomers, is limited due to metabolism-linked hemolytic toxicity in individuals with genetic deficiency in glucose-6-phosphate dehydrogenase. The current study investigated differential metabolism of PQ enantiomers in light of the suggestions that toxicity and efficacy might be largely enantioselective.Stable isotope (13)C-labelled primaquine and its two enantiomers (+)-PQ, (-)-PQ were separately incubated with cryopreserved human hepatocytes. Time-tracked substrate depletion and metabolite production were monitored via UHPLC-MS/MS.The initial half-life of 217 and 65min; elimination rate constants () of 0.19 and 0.64h(-1); intrinsic clearance (Clint) of 2.55 and 8.49 (L/min)/million cells, which when up-scaled yielded Clint of 6.49 and 21.6 (mL/min)/kg body mass was obtained respectively for (+)- and (-)-PQ. The extrapolation of in vitro intrinsic clearance to in vivo human hepatic blood clearance, performed using the well-stirred liver model, showed that the rate of hepatic clearance of (+)-PQ was only 45% that of (-)-PQ. Two major primary routes of metabolism were observed-oxidative deamination of the terminal amine and hydroxylations on the quinoline moiety of PQ. The major deaminated metabolite, carboxyprimaquine (CPQ) was preferentially generated from the (-)-PQ. Other deaminated metabolites including PQ terminal alcohol (m/z 261), a cyclized side chain derivative from the aldehyde (m/z 241), cyclized carboxylic acid derivative (m/z 257), a quinone-imine product of hydroxylated CPQ (m/z 289), CPQ glucuronide (m/z 451) and the glucuronide of PQ alcohol (m/z 437) were all preferentially generated from the (-)-PQ. The major quinoline oxidation product (m/z 274) was preferentially generated from (+)-PQ. In addition to the products of the two metabolic pathways, two other major metabolites were observed: a prominent glycosylated conjugate of PQ on the terminal amine (m/z 422), peaking by 30min and preferentially generated by (+)-PQ; and the carbamoyl glucuronide of PQ (m/z 480) exclusively generated from (+)-PQ.Metabolism of PQ showed enantioselectivity. These findings may provide important information in establishing clinical differences in PQ enantiomers.


McChesney J.D.,Ironstone Separations Inc. | Rodenburg D.L.,Ironstone Separations Inc.
Current Opinion in Biotechnology | Year: 2014

Methodology is reviewed which significantly enhances the economics and efficiency of larger scale preparative normal phase chromatography. Maintenance of hydration of the silica media and regeneration and re-equilibration of the column after each separation is demonstrated to allow repeated use of the column without loss of performance or requirement of repacking. © 2013.


PubMed | University of Mississippi and Ironstone Separations Inc.
Type: | Journal: Rapid communications in mass spectrometry : RCM | Year: 2016

Steviol glycosides with an ent-kaurene core are being used in the Food Industry as non-caloric sweeteners. These compounds are chemically similar in terms of sugar types and sugar arrangements. In order to assign sugar positions, we describe herein, the dissociation pattern for steviol glycosides under varying collision energies.Steviol glycosides (1mg/mL, 2L) were automatically injected into the mass spectrometer by direct infusion using a 100-well tray autosampler. The mass spectrometric analysis was performed using a quadrupole time of flight (QTOF-MS/MS) (Model #G6530A, Agilent Technologies, Palo Alto, CA, USA) equipped with an electro spray ionization source (ESI) with Jet Stream technology.Dissociation of several natural and prepared steviol glycosides were carefully studied by ESI-QTOF-MS/MS ranging collision energies: 10, 20, 30, 40, 50, 60, 70 and 80eV. This procedure allowed us to establish the dissociation pattern for steviol glycosides and thus the sugar arrangement in the branched oligosaccharide portion linked at position C-13 of steviol and also infer the sugar arrangement at C-19.Those steviol glycosides with a monosaccharide or less hindered disaccharides at position C-19 are cleaved at low collision energy (10eV) while highly hindered disaccharides and trisaccharides are cleaved at 40eV. However, sugars attached at C-13 cleave at highest collision energies in the following order: the C-3 sugar, followed by the C-2 sugar and finally the sugar directly linked directly at C-13.


Patent
Ironstone Separations Inc. | Date: 2011-07-07

This application discloses, in part, 1) a stationary phase column and compression designs for preparative chromatography, 2) a method of improving performance of silica gel chromatography by controlling the hydration of silica gel and acidifying the mobile phase, and 3) a method of extending the life of a silica gel column packing by cleaning or regenerating the silica gel stationary phase.


Patent
Ironstone Separations Inc. | Date: 2014-08-22

In one embodiment, the present application discloses compositions and methods of solubilizing pterostilbene or resveratrol, or mixture thereof in aqueous media.


Patent
Ironstone Separations Inc. | Date: 2014-01-03

This application discloses, in part, 1) a stationary phase column and compression designs for preparative chromatography, 2) a method of improving performance of silica gel chromatography by controlling the hydration of silica gel and acidifying the mobile phase, and 3) a method of extending the life of a silica gel column packing by cleaning or regenerating the silica gel stationary phase.

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