RESUMEN
Antioxidant stilbenoids, such as resveratrol, arachidin-1, and arachidin-3, have demonstrated beneficial effects on human health. Although resveratrol is commercially available, arachidin-1 and arachidin-3 are not, resulting in an opportunity to explore purification methods and to confirm biological activity. Recently, Arachis hypogaea hairy root cultures (produced via Agrobacterium rhizogenes-mediated transformation) were reported to secrete stilbenoids into liquid growth media upon elicitation in quantities sufficient for commercial production. The purpose of this study was to purify substantial quantities of resveratrol, arachidin-1, and arachidin-3 from A. hypogaea hairy root cultures using centrifugal partition chromatography (CPC), determine the antioxidant activity of these compounds using the thiobarbituric acid reactive substances (TBARS) assay, and determine the cytotoxicity of the compounds using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In a single run of CPC, resveratrol, arachidin-1, and arachidin-3 were separated to a purity of 97.1%, 97.0%, and 91.8%, respectively. Lipid oxidation was inhibited by a 27 and 7 µM dose for reference standards of resveratrol and arachidin-1, respectively, while oxidation was not inhibited up to a 27 µM dose for reference standard of arachidin-3. Oxidation was inhibited at a 14, 7, and 14 µM doses for CPC-purified resveratrol, arachidin-1, and arachidin-3, respectively. Arachidin-1 and arachidin-3 demonstrated cytotoxicity at 27 and 55 µM in RAW 264.7 and HeLa cell lines, respectively; while resveratrol exhibited no cytotoxicity to either cell line. These results demonstrate the integration of a production and purification system for the manufacturing of A. hypogaea-derived stilbenoids.
Asunto(s)
Antioxidantes/aislamiento & purificación , Arachis/química , Hemiterpenos/aislamiento & purificación , Raíces de Plantas/química , Estilbenos/aislamiento & purificación , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células HeLa , Hemiterpenos/metabolismo , Hemiterpenos/farmacología , Humanos , Ratones , Raíces de Plantas/citología , Resveratrol , Estilbenos/metabolismo , Estilbenos/farmacología , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismoRESUMEN
Cytochrome P450 2D6 (CYP2D6), an important CYP isoform with regard to drug-drug interactions, accounts for the metabolism of approximately 30% of all medications. To date, few studies have assessed the effects of botanical supplementation on human CYP2D6 activity in vivo. Six botanical extracts were evaluated in three separate studies (two extracts per study), each incorporating 16 healthy volunteers (eight females). Subjects were randomized to receive a standardized botanical extract for 14 days on separate occasions. A 30-day washout period was interposed between each supplementation phase. In study 1, subjects received milk thistle (Silybum marianum) and black cohosh (Cimicifuga racemosa). In study 2, kava kava (Piper methysticum) and goldenseal (Hydrastis canadensis) extracts were administered, and in study 3 subjects received St. John's wort (Hypericum perforatum) and Echinacea (Echinacea purpurea). The CYP2D6 substrate, debrisoquine (5 mg), was administered before and at the end of supplementation. Pre- and post-supplementation phenotypic trait measurements were determined for CYP2D6 using 8-h debrisoquine urinary recovery ratios (DURR). Comparisons of pre- and post-supplementation DURR revealed significant inhibition (approximately 50%) of CYP2D6 activity for goldenseal, but not for the other extracts. Accordingly, adverse herb-drug interactions may result with concomitant ingestion of goldenseal supplements and drugs that are CYP2D6 substrates.
Asunto(s)
Citocromo P-450 CYP2D6/metabolismo , Interacciones de Hierba-Droga , Hydrastis/efectos adversos , Fitoterapia , Extractos Vegetales/farmacología , Cimicifuga/metabolismo , Suplementos Dietéticos , Echinacea/metabolismo , Humanos , Hydrastis/metabolismo , Hypericum/metabolismo , Kava/metabolismo , Silybum marianum/metabolismoRESUMEN
Oxygen radical absorbance capacity (ORAC) values showed that methanolic extracts of Albizia julibrissin foliage displayed antioxidant activity. High performance liquid chromatography (HPLC) and mass spectrometry (MS) techniques were utilized in the identification of the compounds. The analysis confirmed the presence of three compounds in A. julibrissin foliage methanolic extract: an unknown quercetin derivative with mass of 610 Da, hyperoside (quercetin-3-O-galactoside), and quercitrin (quercetin-3-O-rhamnoside). Fast performance liquid chromatography (FPLC) was employed to fractionate the crude A. julibrissin foliage methanolic extract into its individual flavonoid components. The flavonoids were quantified in terms of mass and their respective contribution to the overall ORAC value. Quercetin glycosides accounted for 2.0% of total foliage.
Asunto(s)
Albizzia/química , Flavonoides/química , Glicósidos/química , Conservación de los Recursos Energéticos , Hojas de la PlantaRESUMEN
Phytochemical-mediated modulation of cytochrome P450 enzymes (CYPs) may underlie many herb-drug interactions. This study's purpose was to assess the effects of milk thistle and black cohosh supplementation on CYP3A activity and compare them to a clinically recognized inducer, rifampin, and inhibitor, clarithromycin. Healthy volunteers were randomly assigned to receive a standardized milk thistle (900 mg) or black cohosh (80 mg) supplement for 14 days. Subjects also received rifampin (600 mg) and clarithromycin (1000 mg) for 7 days as positive controls for CYP3A induction and inhibition, respectively. Midazolam was administered orally before and after each supplementation and control period. The effects of milk thistle, black cohosh, rifampin, and clarithromycin on midazolam pharmacokinetics were determined using noncompartmental techniques. Unlike those observed for rifampin and clarithromycin, midazolam pharmacokinetics was unaffected by milk thistle or black cohosh. Milk thistle and black cohosh appear to have no clinically relevant effect on CYP3A activity in vivo.
Asunto(s)
Antibacterianos/farmacología , Antibióticos Antituberculosos/farmacología , Cimicifuga/química , Claritromicina/farmacología , Citocromo P-450 CYP3A/metabolismo , Suplementos Dietéticos , Rifampin/farmacología , Silybum marianum/química , Adulto , Área Bajo la Curva , Citocromo P-450 CYP3A/biosíntesis , Inhibidores del Citocromo P-450 CYP3A , Interacciones Farmacológicas , Activadores de Enzimas/farmacología , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Hipnóticos y Sedantes/farmacocinética , Masculino , Midazolam/farmacocinética , Fenotipo , Caracteres SexualesRESUMEN
Kudzu (Pueraria lobata) foliage has been touted as a possible energy crop. High-performance liquid chromatography and mass spectrometry analysis of the methanolic kudzu foliage extracts confirmed the presence of robinin (kaempferol-3-O-robinoside-7-O-rhamnoside). Robinin accounted for 0.65 +/- 0.16% (dry basis) of kudzu biomass. Fast performance liquid chromatography (FPLC) was employed to fractionate robinin from the crude extract. The antioxidant capacity of robinin was evaluated by an oxygen radical absorbance capacity (ORAC) assay. The ORAC values of pure standard were compared with those of the extract fractions. One milligram of the FPLC-fractionated robinin generated an ORAC value of 5.15 +/- 2.00 micromol/mg of Trolox, whereas 1 mg of pure robinin generated an ORAC value of 12.34 +/- 0.45 micromol/mg of Trolox. Because of its antioxidant properties, robinin may be a flavonoid worth extracting prior to energy production.
Asunto(s)
Antioxidantes/análisis , Antioxidantes/química , Flavonoides/análisis , Flavonoides/química , Extractos Vegetales/química , Pueraria/metabolismo , Glicósidos/análisis , Glicósidos/química , Oxidación-Reducción , Extractos Vegetales/análisisRESUMEN
The aqueous extract of American skullcap (Scutellaria lateriflora L. (S. lateriflora), Lamiaceae) has been traditionally used by North American Indians as a nerve tonic and for its sedative and diuretic properties. Recent reports stated that flavonoids and possibly amino acids are responsible for the anxiolytic activity. As a part of our search for environmentally friendly solvents to extract the active components from medicinal plants, we used S. lateriflora in a comparison of accelerated solvent extraction (ASE) using water, and supercritical fluid extraction (SFE) using CO2 and 10% EtOH as modifier, at different temperatures. Flavonoids and amino acids were quantified by HPLC-UV and HPLC-MS, respectively. The flavonoid content was compared with conventional extraction methods (hot water extraction and 70% ethanol). The use of ASE at 85 degrees C with water as solvent gave the best results for flavonoid glycosides and amino acids, whereas SFE gave higher yields of flavonoid aglycones. However, the results obtained for total flavonoids were not significatively superior to hot water extraction or 70% aqueous EtOH extract.
Asunto(s)
Cromatografía con Fluido Supercrítico , Etanol , Extractos Vegetales/química , Scutellaria/química , Agua , Aminoácidos/análisis , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , SolventesRESUMEN
Seeds of milk thistle (Silybum marianum L. Gaertner) contain silymarins and ca. 25% (w/w) of oil. A pre-treatment step involving refluxing with petroleum ether is usually performed before extraction of the silymarins using organic solvents. This paper compares the extraction of whole and defatted milk thistle seeds in various solvents as a function of temperature. The extraction of whole seeds of milk thistle with water at 50, 70 and 85 degrees C was also examined: the yield of silymarin increased with increasing water temperature. In most cases, ethanol at 60 degrees C recovered the largest quantities of silymarins. However, boiling water proved to be an efficient extraction solvent for the more polar silymarins such as taxifolin and silychristin, even when using whole seeds. Extractions of defatted seed meal with boiling ethanol returned maximum yields of 0.62, 3.89, 4.04, and 6.86 mg/g defatted seed of taxifolin, silychristin, silybinin A and silybinin B, respectively. When extracting defatted seed meal with ethanol, yields of taxifolin, silybinin A and silybinin B were, respectively, 6.8-, 0.95-, 1.7- and 1.6-fold higher than when extracting whole seeds. When extracting with boiling water, the yields of silychristin, silybinin A, and silybinin B were 380, 47 and 50% higher for whole seeds compared with defatted seeds.