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1.
Biomed Chromatogr ; 34(3): e4751, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31756271

RESUMEN

A simple, rapid and accurate stability-indicating HPLC assay was developed for the determination of acyclovir and lidocaine in topical formulations. Chromatographic separation of acyclovir and lidocaine was achieved using a reversed-phase C18 column and a gradient mobile phase (20 mm ammonium acetate pH 3.5 in water and acetonitrile). The degradation products of acyclovir and lidocaine in the samples were analyzed by ultra performance liquid chromatography-time of flight mass spectrometry. The HPLC method successfully resolved the analytes from the impurities and degradation products in the topical formulation. Furthermore, the method detected the analytes from the human skin leachables following the extraction of the analytes in the skin homogenate samples. The method showed linearity over wide ranges of 5-500 and 10-200 µg/ml for acyclovir and lidocaine in the topical product, respectively, with a correlation coefficient (r2 ) >0.9995. The relative standard deviations for precision, repeatability, and robustness of the method validation assays were <2%. The skin extraction efficiency for acyclovir and lidocaine was 92.8 ± 0.7% and 91.3 ± 3.2%, respectively, with no interference from the skin leachables. Thus, simultaneous quantification of acyclovir and lidocaine in the topical formulations was achieved.


Asunto(s)
Aciclovir/análisis , Aciclovir/química , Cromatografía Líquida de Alta Presión/métodos , Lidocaína/análisis , Lidocaína/química , Estabilidad de Medicamentos , Humanos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Piel/química
2.
AAPS PharmSciTech ; 21(8): 304, 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-33150503

RESUMEN

Hispolon is a small molecular weight polyphenol that has antioxidant, anti-inflammatory, and anti-proliferative activities. Our recent study has demonstrated hispolon as a potent apoptosis inducer in melanoma cell lines. Doxorubicin is a broad spectrum first-line treatment for various kinds of cancers. In this study, co-delivery of doxorubicin and hispolon using a liposomal system in B16BL6 melanoma cell lines for synergistic cytotoxic effects was investigated. Liposomes were prepared using a lipid film hydration method and loaded with doxorubicin or hispolon. The formulations were characterized for particle size distribution, release profile, and encapsulation efficiency (EE). In addition, in vitro cytotoxicity, in vitro cell apoptosis, and cellular uptake were evaluated. Liposomes exhibited small particle size (mean diameter ~ 100 nm) and narrow size distribution (polydispersity index (< 0.2) and high drug EE% (> 90%). The release from liposomes showed slower release compared to free drug solution as an additional time required for the release of drug from the liposome lipid bilayer. Liposome loaded with doxorubicin or hispolon exhibited significantly higher cytotoxicity against B16BL6 melanoma cells as compared to doxorubicin solution or hispolon solution. Likewise, co-delivery of hispolon and doxorubicin liposomes showed two-fold and three-fold higher cytotoxicity, as compared to hispolon liposomes or doxorubicin liposomes, respectively. In addition, co-delivery of doxorubicin and hispolon in liposomes enhanced apoptosis more than the individual drugs in the liposome formulation. In conclusion, the co-delivery of hispolon and doxorubicin could be a promising therapeutic approach to improve clinical outcomes against melanoma.


Asunto(s)
Antibióticos Antineoplásicos/uso terapéutico , Catecoles/administración & dosificación , Doxorrubicina/análogos & derivados , Melanoma/tratamiento farmacológico , Animales , Antibióticos Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Humanos , Membrana Dobles de Lípidos , Melanoma/patología , Tamaño de la Partícula , Polietilenglicoles/administración & dosificación
3.
Rapid Commun Mass Spectrom ; 31(5): 419-429, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-27957780

RESUMEN

RATIONALE: Estuaries are dynamic ecosystems, providing vital habitat for unique organisms of great ecological and commercial importance. The influx of natural and synthetic steroid hormones into estuaries poses risks to these organisms and to broader ecosystem health. However, detecting these trace level pollutants in estuarine water and sediment requires improved analytical techniques. METHODS: We describe an optimized ultrahigh-performance chromatography/tandem mass spectrometry (UHPLC/MS/MS) method for simultaneous quantitation of four classes of steroid hormones (estrogens, glucocorticoids, androgens and progestins) in sediment samples collected from an Alabama estuary. Sediment samples were homogenized using Hydromatrix (HM) sorbent and extracted with methanol and water (70%, v/v). Centrifuged extracts were purified using an Agilent Bond Elut QuEChERS dispersive-SPE kit to eliminate interfering substances that could negatively influence the ionization process. Chromatographic separation was achieved on a Poroshell 120 Phenyl-Hexyl column using an Agilent 1290 Infinity II UHPLC pump. Quantitation was carried out using an Agilent triple quadrupole mass spectrometer equipped with a JetStream/ESI source in dual mode. RESULTS: Chromatographic separation and better peak resolution were accomplished on an Agilent Poroshell 120 Phenyl-Hexyl column using a binary gradient method with a mobile phase consisting of 1 mM ammonium fluoride in water and a mixture of methanol/acetonitrile. A dynamic multiple reaction monitoring (MRM) method was developed by optimizing various MS parameters. The method was used to analyze target steroid hormones in estuarine sediments. A total of ten steroid hormones were detected at trace amounts in estuarine sediments. CONCLUSIONS: The optimized analytical method described here involves reasonably simple sample preparation and simultaneous trace level quantitation of four classes (estrogens, glucocorticoids, androgens and progestins) of steroid hormones in a single experimental run. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Disruptores Endocrinos/análisis , Sedimentos Geológicos/química , Esteroides/análisis , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisis , Alabama , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
4.
Bioorg Med Chem ; 23(9): 2148-2158, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25842364

RESUMEN

Phytochemicals play an important role in cancer therapy. Hispolon and 26 of its analogs (9 known and 17 new) were synthesized and evaluated for their antiproliferative activities in a panel of six independent human cancer cell lines using the in vitro cell-based MTT assay. Among the hispolon analogs tested, compound VA-2, the most potent overall, produced its most significant effect in the colon cancer cell lines HCT-116 (IC50 1.4 ± 1.3 µM) and S1 (IC50 1.8 ± 0.9 µM) compared to its activity in the normal HEK293/pcDNA3.1 cell line (IC50 15.8±3.7 µM; p<0.01 for each comparison). Based on our results, VA-2 was about 9- to 11-times more potent in colon cancer cells and 2- to 3-times more potent in prostate cancer cells compared to HEK293/pcDNA3.1 cells. Morphological analysis of VA-2 showed significant reduction of cell number, while the cells' sizes were also markedly increased and were obvious at 68 h of treatment with 1 µM in HCT-116 (colon) and PC-3 (prostate) cancer cells. A known analog, compound VA-4, prepared by simple modifications on the aromatic functional groups of hispolon, inhibited prostate and colon cancer cell lines with IC50 values <10 µM. In addition, hispolon isoxazole and pyrazole analogs, VA-7 and VA-15 (known), respectively, have shown significant activity with the mean ICv values in the range 3.3-10.7 µM in all the cancer cell lines tested. Activity varied among the analogs in which aromatic functional groups and ß-diketone functional groups are modified. But the activity of analogs VA-16 to VA-27 was completely lost when the side chain double-bond was hydrogenated indicating the crucial role of this functionality for anticancer activity. Furthermore, many of the compounds synthesized were not substrates for the ABCB1-transporter, the most common cause of multidrug resistance in anti-cancer drugs, suggesting they may be more effective anticancer agents.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Catecoles/farmacología , Diseño de Fármacos , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Catecoles/síntesis química , Catecoles/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Perros , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HEK293 , Humanos , Células MCF-7 , Células de Riñón Canino Madin Darby/efectos de los fármacos , Ratones , Estructura Molecular , Células 3T3 NIH , Relación Estructura-Actividad
5.
Biomed Chromatogr ; 29(5): 716-21, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25298219

RESUMEN

A simple, sensitive and stability-indicating high-performance liquid chromatographic (HPLC) assay method was developed and validated for a bioactive peptide, lysine-proline-valine (KPV) in aqueous solutions and skin homogenates. Chromatographic separation was achieved on a reversed phase Phenomenex C18 column (4.6 × 250 mm, packed with 5 µm silica particles) with a gradient mobile phase consisting of 0.1% trifluoroacetic acid (TFA) in water (A) and 0.1% TFA in acetonitrile (B). The proposed HPLC method was validated with respect to accuracy, precision, linearity, repeatability, limit of detection (LOD) and limit of quantitation (LOQ). The calibration curve was linear with a correlation coefficient (r) of 0.9999. Relative standard deviation values of accuracy and precision experiments were <2. The LOD and LOQ of KPV were 0.01 and 0.25 µg/mL, respectively. Under stress conditions (acid, alkali and hydrogen peroxide) KPV yielded lys-pro-diketopiperazine as major degradation product, which was identified by flow injection MS analysis. The developed HPLC method was found to be efficient in separating the active peptide from its degradation products generated under various stress conditions. Also, the validated method was able to separate KPV from other peaks arising from endogenous components of the skin homogenate.


Asunto(s)
Antiinflamatorios/química , Cromatografía Líquida de Alta Presión/métodos , Péptidos/química , Piel/química , Estabilidad de Medicamentos , Humanos , Límite de Detección
6.
Phytother Res ; 29(9): 1404-1411, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26096804

RESUMEN

Traditional knowledge, in vitro studies, and studies using animal models suggest that Tridax procumbens L. exhibits blood glucose-lowering properties and antiinflammatory effects. In this study, we evaluated the blood glucose-lowering effect of T. procumbens supplementation in individuals with type 2 diabetes. An extract (asava) of T. procumbens L. was prepared following Ayurveda guidelines. Chemical and microbial analyses indicated presence of phenolics, flavonoids, and carotenoids, and absence of microbial contamination, aflatoxins, heavy metals, and pesticide residues. A chemical fingerprint of T. procumbens L. asava, developed using Ultra high pressure liquid chromatography/electron spray ionization-mass spectrometry (UPLC/ESI-MS) in negative mode, suggest the presence of several compounds including polyphenols. T. procumbens asava demonstrated strong total antioxidant capacity, Fe3+ reducing potential, Fe2+ chelation, H2 O2 scavenging activity, and inhibition of lipid peroxidation. We recruited 20 type 2 diabetic individuals from Kolhapur, India. Participants received 15 mL of T. procumbens asava, twice daily, for 4 weeks, while continuing their prescribed antidiabetic medications. Fasting blood glucose decreased by 11% in men (p < 0.01) and 20% in women (p < 0.05), and post-prandial blood glucose concentrations were lowered by 26% in men (p < 0.001) and 29% in women (p < 0.001) following 4 weeks of asava supplementation. No adverse events or side effects were reported. This is the first clinical study demonstrating a significant blood glucose-lowering effect of T. procumbens asava in type 2 diabetes. Copyright © 2015 John Wiley & Sons, Ltd.

7.
Endocrinology ; 164(12)2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37767721

RESUMEN

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are widely used in a variety of industrial processes and manufacturing of consumer products. Current efforts by the manufacturing industry will limit use of long-chain or legacy PFAS represented by perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) and replace with short-chain or emerging PFAS such as perfluorobutanoic acid (PFBA) and perfluorobutane sulfonic acid (PFBS). However, there is little to no information on the toxicity of new and emerging PFAS. Therefore, we performed experiments in growing Long-Evans male rats to investigate effects of low-dose prepubertal and pubertal exposures to PFAS on gonadal steroid hormone secretion. The results demonstrated that both legacy and emerging PFAS have the capacity to regulate testicular steroidogenesis. For instance, prepubertal exposures to PFOS, PFBA, and PFBS increased serum and testicular testosterone concentrations. Exposure to PFBA increased testicular 17ß-estradiol (E2) concentrations, and PFOS and PFBS both decreased serum E2 concentrations while stimulating testicular E2 secretion. The data also demonstrated additive effects due to legacy and emerging PFAS mixtures compared with the individual chemicals. The gonadal effects due to PFAS exposures occurred at nanomolar concentrations, which approximate PFAS levels in the environment. Taken together, the present study supports the need for development of cost-effective and sustainable filtration media for different processes to remove PFAS from water and other sources of exposure. Current action by regulatory agencies such as the US Environmental Protection Agency to limit use of PFAS in the manufacture of consumer products will protect public health.


Asunto(s)
Ácidos Alcanesulfónicos , Fluorocarburos , Ratas , Animales , Masculino , Ratas Long-Evans , Ácidos Alcanesulfónicos/toxicidad , Fluorocarburos/toxicidad , Gónadas
8.
Pharm Biol ; 50(10): 1289-96, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22900515

RESUMEN

CONTEXT: Euterpe oleracea Mart. (Arecaceae) fruits and their dietary supplements are gaining much popularity internationally. Anthocyanins and their aglycons are responsible for the dense color of açaí fruit and are associated with a wide spectrum of health promoting effects. OBJECTIVE: Quantitative analysis of anthocyanins in açaí dietary supplement raw materials; processed açaí powder (ADSR-1), organic açaí powder (ADSR-2), and nonorganic açaí powder (ADSR-3) by quadrupole-time-of-flight liquid chromatography/mass spectrometry (Q-TOF LC/MS) have been reported in this study. MATERIALS AND METHODS: The chromatographic separation for anthocyanins was achieved using a C-18 column with a gradient of 0.1% formic acid in water and 0.1% formic acid in methanol and acetonitrile (50:50, v/v). MS and MS/MS experiments were carried out on an electrospray ionization-Q-TOF LC/MS. RESULTS: Except for ASDR-2, all the açaí samples were found to have cyanidin 3-glucoside (1), cyanidin 3-sambubioside (2), cyanidin 3-rutinoside (3), and peonidin 3-rutinoside (4). ASDR-2 contained anthocyanins 1 and 3. Among the açaí samples quantified, ADSR-3 showed higher concentration of anthocyanins compared to other raw materials and capsules tested in this study. DISCUSSION AND CONCLUSION: The anthocyanins 1-4 present in ADSR-3 were 27.13 ± 0.37, 1.76 ± 0.04, 31.07 ± 0.49, and 3.46 ± 0.08 mg/100 g dry wt, respectively. The LOQ values for anthocyanins 1-4 were in the range of 2.44-9.76 ng/mL. Accuracy of the method was assessed by performing a recovery experiments. The intraday and interday variations (RSDs) were <10%. This is the first report on quantitation of anthocyanins in açaí dietary supplement raw materials and capsules.


Asunto(s)
Antocianinas/análisis , Arecaceae/química , Suplementos Dietéticos/análisis , Antocianinas/aislamiento & purificación , Cápsulas , Cromatografía Liquida/métodos , Límite de Detección , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
9.
Sci Total Environ ; 836: 155524, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35489494

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) have been previously detected near suspected sources in Alabama, but the overall extent of contamination across the state is unknown. This study evaluated the spatial distribution of 17 PFAS within the ten major river basins in Alabama and provided insights into their transport and fate through a mass flux analysis. Six PFAS were identified in 65 out of the 74 riverine samples, with mean ∑6PFAS levels of 35.2 ng L-1. The highest ∑6PFAS concentration of 237 ng L-1 was detected in the Coosa River, a transboundary river that receives discharges from multiple sources in Alabama and Georgia. PFAS distribution was not observed to be uniform across the state: while the Coosa, Alabama, and Chattahoochee rivers presented relatively high mean ∑6PFAS concentrations of 191, 100 and 28.8 ng L-1, respectively, PFAS were not detected in the Conecuh, Escatawpa, and Yellow rivers. Remaining river systems presented mean ∑6PFAS concentrations between 7.94 and 24.7 ng L-1. Although the short-chain perfluoropentanoic acid (PFPeA) was the most detected analyte (88%), perfluorobutanesulfonic acid (PFBS) was the substance with the highest individual concentration of 79.4 ng L-1. Consistent increases in the mass fluxes of PFAS were observed as the rivers flowed through Alabama, reaching up to 63.3 mg s-1, indicating the presence of numerous sources across the state. Most of the mass inputs would not have been captured if only aqueous concentrations were evaluated, since concentration is usually heavily impacted by environmental conditions. Results of this study demonstrate that mass flux is a simple and powerful complementary approach that can be used to broadly understand trends in the transport and fate of PFAS in large river systems.


Asunto(s)
Ácidos Alcanesulfónicos , Fluorocarburos , Contaminantes Químicos del Agua , Alabama , Ácidos Alcanesulfónicos/análisis , Monitoreo del Ambiente/métodos , Fluorocarburos/análisis , Ríos , Agua/análisis , Contaminantes Químicos del Agua/análisis
10.
Planta Med ; 77(15): 1749-53, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21567357

RESUMEN

Our current research on applications of mass spectrometry to natural product drug discovery against malaria aims to screen plant extracts for new ligands to Plasmodium falciparum thioredoxin reductase (PfTrxR) followed by their identification and structure elucidation. PfTrxR is involved in the antioxidant defense and redox regulation of the parasite and is validated as a promising target for therapeutic intervention against malaria. In the present study, detannified methanol extracts from Guatteria recurvisepala, Licania kallunkiae, and Topobea watsonii were screened for ligands to PfTrxR using ultrafiltration and liquid chromatography/mass spectrometry-based binding experiments. The PfTrxR ligand identified in the extract of Guatteria recurvisepala displayed a relative binding affinity of 3.5-fold when incubated with 1 µM PfTrxR. The ligand corresponding to the protonated molecule m/z 282.2792 [M+ H]+ was eluted at a retention time of 17.95 min in a 20-min gradient of 95% B consisting of (A) 0.1%formic acid in 95% H2O-5% ACN, and (B) 0.1% formic acid in 95% ACN-5% H2O in an LC-QTOF-MS.Tandem MS of the protonated molecule m/z 282.2792 [M + H]+, C18H36NO (DBE: 2; error: 1.13 ppm) resulted in two daughter ions m/z 265.2516[M + H-NH3]+ (DBE: 3; error: 0.35 ppm) and m/z 247.2405 [M + H-NH3-H2O] +, (DBE: 4; error:2.26 ppm). The PfTrxR ligand was identified as oleamide and confirmed by comparison of the retention time, molecular formula, accurate mass,and double bond equivalence with the standard oleamide. This is the first report on the identification of oleamide as a PfTrxR ligand from Guatteria recurvisepala R. E. Fr. and the corresponding in vitro activity against P. falciparum strain K1 (IC50 4.29 µg/mL).


Asunto(s)
Antimaláricos/química , Guatteria/química , Ácidos Oléicos/química , Extractos Vegetales/química , Plasmodium falciparum/enzimología , Reductasa de Tiorredoxina-Disulfuro/metabolismo , Animales , Antimaláricos/aislamiento & purificación , Línea Celular , Supervivencia Celular , Cromatografía Liquida , Chrysobalanaceae/química , Descubrimiento de Drogas , Concentración 50 Inhibidora , Ligandos , Espectrometría de Masas , Melastomataceae/química , Ácidos Oléicos/aislamiento & purificación , Panamá , Extractos Vegetales/aislamiento & purificación , Ratas , Estándares de Referencia , Ultrafiltración
11.
Artículo en Inglés | MEDLINE | ID: mdl-19454555

RESUMEN

Tea prepared from the aerial parts of Antigonon leptopus is used as a remedy for cold and pain relief in many countries. In this study, A. leptopus tea, prepared from the dried aerial parts, was evaluated for lipid peroxidation (LPO) and cyclooxygenase (COX-1 and COX-2) enzyme inhibitory activities. The tea as a dried extract inhibited LPO, COX-1 and COX-2 enzymes by 78%, 38% and 89%, respectively, at 100 µg/mL. Bioassay-guided fractionation of the extract yielded a selective COX-2 enzyme inhibitory phenolic aldehyde, 2,3,4-trihydroxy benzaldehyde. Also, it showed LPO inhibitory activity by 68.3% at 6.25 µg/mL. Therefore, we have studied other hydroxy benzaldehydes and their methoxy analogs for LPO, COX-1 and COX-2 enzymes inhibitory activities and found that compound 1 gave the highest COX-2 enzyme inhibitory activity as indicated by a 50% inhibitory concentration (IC(50)) at 9.7 µg/mL. The analogs showed only marginal LPO activity at 6.25 µg/mL. The hydroxy analogs 6, 7 and 9 showed 55%, 61% and 43% of COX-2 inhibition at 100 µg/mL. However, hydroxy benzaldehydes 3 and 12 showed selective COX-1 inhibition while compounds 4 and 10 gave little or no COX-2 enzyme inhibition at 100 µg/mL. At the same concentration, compounds 14, 21 and 22 inhibited COX-1 by 83, 85 and 70%, respectively. Similarly, compounds 18, 19 and 23 inhibited COX-2 by 68%, 72% and 70%, at 100 µg/mL. This is the first report on the isolation of compound 1 from A. leptopus tea with selective COX-2 enzyme and LPO inhibitory activities.

12.
Anal Chem ; 82(9): 3616-21, 2010 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-20394394

RESUMEN

Shikimate kinase (SK) and other enzymes in the shikimate pathway are potential targets in the discovery of antimicrobial agents. In the current study, an ultrafiltration-liquid chromatography/mass spectrometry (UF-LC/MS) ligand based binding assay and an LC/MS based functional assay for Mycobacterium tuberculosis shikimate kinase (MtSK) were developed. Compounds 1, 2, 3, and 4 were tested for MtSK (1 microM) at a concentration of 1 microM. In order to evaluate the MtSK inhibitory activity, compounds 1-4 were tested at concentrations ranging from 0.05 to 1 microM, and the enzymatic activity was assessed by quantifying shikimate-3-phosphate (S3P) by LC/MS after 60 min incubation with 2 mM shikimic acid as a substrate. The EC(50) values of compounds 1, 2, 3, and 4 were 0.30, 0.24, 0.07, and 0.18 microM, respectively. The ligands and the S3P were analyzed using positive and negative electrospray LC/MS, respectively. The calibration curve for S3P was prepared with concentrations ranging from 4 to 125 microg/mL, and the lower detection limit (LOD) of S3P was identified as 1.95 microg/mL (9.75 ng on-column). This is the first application of UF-LC/MS and LC/MS in the development of ligand-binding and functional assays, respectively as a useful approach to screen MtSK inhibitors.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Mycobacterium tuberculosis/enzimología , Fosfotransferasas/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Ligandos , Límite de Detección , Estructura Molecular , Unión Proteica , Ácido Shikímico/metabolismo , Transducción de Señal
13.
Phytother Res ; 23(7): 987-92, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19152372

RESUMEN

Investigation of the methanol extract of Aswagandha (Withania somnifera) roots for bioactive constituents yielded a novel withanolide sulfoxide compound (1) along with a known withanolide dimer ashwagandhanolide (2) with an S-linkage. The structure of compound 1 was established by extensive NMR and MS experiments. Compound 1 was highly selective in inhibiting cyclooxygenase-2 (COX-2) enzyme by 60% at 100 microm with no activity against COX-1 enzyme. The IC(50) values of compound 1 against human gastric (AGS), breast (MCF-7), central nervous system (SF-268) and colon (HCT-116) cancer cell lines were in the range 0.74-3.63 microm. Both S-containing dimeric withanolides, 1 and 2, completely suppressed TNF-induced NF-kappaB activation when tested at 100 microm. The isolation of a withanolide sulfoxide from W. somnifera roots and its ability to inhibit COX-2 enzyme and to suppress human tumor cell proliferation are reported here for the first time. In addition, this is the first report on the abrogation of TNF-induced NF-kappaB activation for compounds 1 and 2.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , FN-kappa B/antagonistas & inhibidores , Sulfóxidos/farmacología , Witanólidos/farmacología , Línea Celular Tumoral , Ergosterol/análogos & derivados , Ergosterol/farmacología , Humanos , Estructura Molecular , Extractos Vegetales/farmacología , Raíces de Plantas/química , Sulfóxidos/aislamiento & purificación , Withania/química , Witanólidos/aislamiento & purificación
14.
Chemosphere ; 237: 124472, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31394445

RESUMEN

Endocrine disrupting chemicals (EDCs) are natural or synthetic compounds that can interfere with the endocrine systems of humans and wildlife. EDCs can pass through wastewater treatment systems, or run off from urban areas or agricultural operations, into natural water bodies, exposing resident and migratory organisms to complex EDC mixtures. Some phytoestrogenic polyphenolics (PEPP) are known or suspected EDCs; however, their contribution to total EDC burden in natural surface water systems is largely unknown. We describe a rapid, sensitive, and reproducible quantitative method for analysis of 15 PEPP in estuarine sediment and water, using ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-MS/MS). The method provides excellent peak resolution, peak separation, and rapid run times (method separation/total run time: 8/12.5 min). With two exceptions, spiking experiments demonstrated that the percent recoveries for target PEPP in sediment and water samples were within acceptable analytical validation limits. LOD and LOQ values ranged from 0.004 to 0.010 ng/injection and 0.013-0.032 ng/injection, respectively. The validated method was used for PEPP analysis of sediment and water samples collected from 11 locations within the Perdido Bay estuary in coastal Alabama. No PEPP above the LOD were detected in sediment samples. The mammalian-derived lignin enterolactone was observed at low concentrations in water throughout the estuary, and significantly, at elevated concentrations at two locations associated with small-scale septic systems (3.66 ±â€¯0.27 ng L-1 and 4.01 ±â€¯0.33 ng L-1) and a large wastewater treatment system (4.56 ±â€¯0.24 ng L-1 and 5.69 ±â€¯0.43 ng L-1).


Asunto(s)
4-Butirolactona/análogos & derivados , Disruptores Endocrinos/análisis , Estuarios , Lignanos/análisis , Fitoestrógenos/análisis , Contaminantes Químicos del Agua/análisis , 4-Butirolactona/análisis , Alabama , Cromatografía Líquida de Alta Presión/métodos , Monitoreo del Ambiente , Humanos , Espectrometría de Masas en Tándem/métodos , Aguas Residuales/química
15.
Food Chem ; 110(4): 991-6, 2008 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26047291

RESUMEN

The tender shoots of Calamus ornatus, one of the food items consumed by the native people, Kanawan Aytas, in the Bataan region of the Philippines, have not been studied before. A bioassay-guided investigation of its methanolic extract afforded non-nutritive functional agents (NFAs), steroidal saponins 1-3, along with its aglycone (4). The NFAs 1-4 inhibited cyclooxygenase enzymes, COX-1 and -2, by 47%, 43%, 33%, and 53% and 71%, 75%, 78%, and 73%, respectively, at 28.2, 24.2, 21.2 and 60.4µM. Treatment of breast (MCF-7), CNS (SF-268), lung (NCI-H460), colon (HCT-116) and gastric (AGS) cancer cell lines with the extract at 100µg/ml reduced cell proliferation. Similarly, the pure NFAs 2 and 3 reduced the cell viability of breast, CNS, lung, colon and gastric cancer cell lines by 37.5%, 22.4%, 53.3%, 58.2%, 40.3% and 29.8%, 21.3%, 45.6%, 37.1%, 25.0%, respectively, at 24.2 and 21.2µM. The 50% reduction in cell viability (IC50) concentrations of 2 and 3 against these cancer cell lines were 8.8, 6.1, 7.5, 23.8, 12.1 and 3.8, 7.1, 3.3, 14.3, 12.1µM, respectively. This is the first report on the isolation of steroidal saponins from C. ornatus shoots and their antiinflammatory and tumor cell proliferation inhibitory activities. Therefore, our results suggest that the Kanawan Aytas may yield health benefits from rattan-shoots in their diet.

16.
Talanta ; 190: 95-102, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30172548

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) represent a large group of synthetic organic compounds which, as a result of their unique chemical properties, render them extremely recalcitrant to environmental degradation. Research concerning the environmental, ecological, and human health effects of PFAS has focused on long aliphatic chain (> C7) compounds having no ether bonds. For new, less studied, or previously unknown PFAS (≤ C7 with ether bonds), there is little to no information about their environmental behavior, transport, fate, exposure, and toxicological effects. LC-MS/MS has proven effective for detection and quantitation of some PFAS, however, straightforward analytical methods for simultaneous trace quantitation of broad mixtures of PFAS in varied complex environmental media, available to a wide range of researchers and also suitable for routine monitoring, remain critical needs. Here we describe a simple, rapid, sensitive, and reproducible quantitative analytical method for trace analysis and monitoring of 23 PFAS in estuarine water, using ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-MS/MS). The developed MRM method allows simultaneous trace quantitation of a broad mixture of PFAS, including 13 perfluoroalkyl carboxylic acids, 8 perfluoroalkyl sulfonates, and 2 short-chain perfluoroethers. The method provides better peak resolution and peak separation, and shorter run times (method separation/total run time: 6/8 min) compared to those of existing analytical methods. Percent recoveries for the validated method ranged from 78.54 to 112.61. LOD and LOQ values ranged from 0.48 to 1.68 pg/injection and 1.71 to 5.40 pg/injection, respectively. The validated method was used for quantitative PFAS analysis of estuarine water samples collected from 16 locations within the Perdido Bay estuary in coastal Alabama.

17.
J Agric Food Chem ; 55(20): 8165-9, 2007 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-17822290

RESUMEN

The red coloration of apple skin is mainly due to anthocyanins that are reported to possess health benefits. The aim of the present study was to determine the anthocyanin content in three underutilized Malus pumila Mill cultivars, Cranberry, Kerr, and Niedzwetzkyana, and confirm their anti-inflammatory and antioxidant activities. Our analysis revealed that the three cultivars studied contained primarily cyanidin-3-O-glucosyl rutinoside (1) at >99%. The anthocyanin was purified by C-18 medium pressure liquid chromatography and characterized by NMR spectral methods. The quantification of anthocyanins in M. pumila cultivars revealed that Cranberry, Kerr, and Niedzwetzkyana contained 1.12, 0.55, and 0.36 mg/g of fresh weight of 1, respectively. The lipid peroxidation (LPO) and cyclooxygenase enzyme (COX) inhibitory activities of 1 in water were compared with the activities of cyanidin-3-O-rutinoside (2) and cyanidin-3-O-glucoside (3) found in cherries and berries. There is a significant increase in LPO and COX enzyme-inhibitory activities of anthocyanin when tested in water compared to using dimethylsulfoxide as the carrier. The LPO inhibition of anthocyanins 1, 2, and 3 were 53.3, 68.3, and 87.9, respectively, at a 0.25 microM concentration. They inhibited the COX-1 enzyme by 42.7, 45.2, and 50.4 and COX-2 by 52.7, 61.5, and 68.5, respectively, at 5 microM. The LPO inhibitory values for commercial standards, BHA, BHT, and TBHQ, were 85, 89, and 94%, respectively at 1 microM. Similarly, positive controls aspirin, celecoxib, and robecoxib inhibited COX-1 and -2 enzymes by 68.6, 40.7, and 0% and 26.6, 72.2, and 92.4%, respectively, at 60, 26, and 32 nM.


Asunto(s)
Antocianinas/análisis , Frutas/química , Malus/química , Antocianinas/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Glucósidos/análisis , Especificidad de la Especie
18.
J Agric Food Chem ; 52(23): 6916-9, 2004 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-15537296

RESUMEN

This study was performed to investigate the free radical scavenging active components from in vitro propagated medicinal herbs of the genus Dendrobium, namely, Dendrobium tosaense Makino and Dendrobium moniliforme SW, using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical antioxidative assay. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half-strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by reculturing on full-strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose, and 0.9% Difco agar. Healthy plantlets transferred to plastic trays containing moss or moss and tree fern successfully acclimatized (84-100%) in the greenhouse. Extracts were prepared from plants grown in the greenhouse for a period of 6 months. Methanolic extracts of D. tosaense and D. moniliforme scavenged DPPH at 95.9 and 83.4%, respectively, at a concentration of 0.4 mg/mL. Therefore, methanolic solubles of D. tosaense and D. moniliforme were subjected to bioguided fractionation and separation by column chromatographic methods individually. After chromatographic separation of these crude extracts, the obtained fractions (Dm 1, Dm 2, Dm 3, Dt 1, Dt 2, and Dt 3) were tested for their activity. Among them, fractions Dm 2 and Dt 1 showed significant antioxidant activity by DPPH radical antioxidative assay. Active fractions were purified further by column chromatography and resulted in identification of the antioxidant components alkyl ferulates from D. moniliforme and quercetin from D. tosaense.


Asunto(s)
Dendrobium/química , Depuradores de Radicales Libres/aislamiento & purificación , Compuestos de Bifenilo , Fraccionamiento Químico , Dendrobium/crecimiento & desarrollo , Picratos/química , Extractos Vegetales/química
19.
J Agric Food Chem ; 51(1): 95-9, 2003 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12502391

RESUMEN

Streptomyces padanus strain PMS-702 is an antagonist of Rhizoctonia solani AG-4, the causal agent of damping-off of cabbage. Treatment of cabbage seeds with the culture filtrate of S. padanus strain PMS-702 was effective in reducing the incidence of damping-off of cabbage. The major active ingredient from the culture filtrate of S. padanus strain PMS-702 was purified by silica gel column chromatography and identified as the polyene macrolide, fungichromin, by NMR and mass spectral data. Bioassay studies showed that fungichromin had a strong antifungal activity against R. solani AG-4, and its minimum inhibitory concentration (over 90% inhibition) was found to be 72 microg/mL. This is the first report of fungichromin from S. padanus as an active ingredient for the control of Rhizoctonia damping-off of cabbage.


Asunto(s)
Fungicidas Industriales/farmacología , Polienos/análisis , Rhizoctonia/efectos de los fármacos , Streptomyces/química , Brassica/microbiología , Macrólidos , Estructura Molecular , Polienos/aislamiento & purificación , Polienos/farmacocinética
20.
Food Chem ; 134(2): 1156-64, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23107743

RESUMEN

Chemical fingerprinting and mass profiling methods to identify biologically active compounds in botanical dietary supplements is gaining much attention in recent years. Euterpe oleracea (açaí) has been reported to be rich in health-beneficial chemical constituents. We have developed LC/MS based fingerprinting and mass profiling methods to identify fatty acids, anthocyanins and non-anthocyanin polyphenols in three processed raw materials; non-organic açaí powder (ADSR-1), raw-organic açaí powder (ADSR-2) and freeze-dried açaí powder (ADSR-3) that are used in the preparation of botanical dietary supplements. For LC/MS analysis of fatty acids and non-anthocyanin polyphenols, the açaí samples were extracted sequentially with dichloromethane followed by methanol. To study fingerprinting analysis of anthocyanins, açaí samples were extracted with acidic methanol-water. The LC separation of fatty acids, non-anthocyanin polyphenols and anthocyanins in açaí raw materials was achieved using a C18 column with a gradient mobile phase consisting of solvents A (0.1% formic acid in water), and B (0.1% formic acid in methanol). MS experiments were carried out with negative and positive mode electrospray ionization. LC/MS analysis of dichloromethane extracts of (ADSR-1), (ADSR-2) and (ADSR-3) açaí powders have shown to contain fatty acids, γ-linolenic acid, linoleic acid, palmitic acid, and oleic acid. Whereas, the fingerprinting analysis of methanol extracts of ADSR-1, ADSR-2 and ADSR-3 led to the identification of phenolic acids, anthocyanin and non-anthocyanin polyphenols. The results from our study may be useful for the authentication and quality assessment of açaí dietary supplement raw materials.


Asunto(s)
Arecaceae/química , Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Espectrometría de Masas/métodos , Extractos Vegetales/análisis , Antocianinas/análisis , Antocianinas/aislamiento & purificación , Ácidos Grasos/análisis , Ácidos Grasos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación
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