Authors:W. J. Szypuła, A. K. Kiss, A. Pietrosiuk, M. Świst, W. Danikiewicz, and O. Olszowska
This article is the first report describing a new validated method to determine the content of HupA in Huperzia selago (Huperziaceae) from wild population and obtained in in vitro culture using the chaotropic mobile phase. An aqueous-organic (acetonitrile) mobile phase with an added chaotropic salt (NaPF6) was used. The system of mobile phases ensured very high selectivity and efficiency at up to N = 6683 ± 963 theoretical plates calculated for isocratic mode. A Hypercosil GOLD column, C18 250 × 4.6 mm, and a Hypercosil GOLD precolumn, 5UM 10 × 4 mm, were employed for detection at four wavelengths, 230 nm being analytical. The regression coefficient (R2) of the calibration was 0.9993 over the range 25–1252 μg mL−1. The recovery rates were 98.36–105.1% with RSD <2.9%. The intra- and inter-day precisions, expressed as RSD, ranged from 1.2% to 2.7%. LOD for HupA was 14 ng mL−1 for a signal-to-noise ratio of 3:1. The limit of quantification was 140 ng mL−1. The huperzine A (HupA) content of the plant material ranged from 0.65 mg g−1 dry weight (d.w.) to 1.59 mg g−1 d.w. (material from wild plants) and from 0.44 to 1.10 mg g−1 d.w. (material from in vitro cultures). Interestingly, in our study, plants of H. selago derived from wild population had one of the highest HupA concentrations recorded for a club moss (1.59 mg g−1 d.w.). The findings demonstrate that H. selago, found in Europe and North America, is an alternative source of HupA, richer than H. serrata. In order to confirm that HupA was present in the alkaloid extracts, HPLC-ESI-MS/MS analyses of the patterns were performed in the positive ion mode. The fragmentation quasi-molecular ion of the standard HupA (m/z = 243, [M+H]+) and the ion with m/z = 243 found in the samples were identical, confirming the compound as HupA.
Authors:Árpád Illés, Csaba Bojtor, Seyed Mohammad Nasir Mousavi, L. Csaba Marton, Péter Ragán, and János Nagy
rootworm contamination, of which the important advantages of the former modeling methods (visual calculation methods, sticky insect traps) are their low costs and their easy and quick application. These methods provide a relative estimate for population
Authors:A. Ochoa, J. Fechine, J.C. Escalona, J. García, S.G. dos Santos, and M. Sobral da Silva
Excoecaria lucida Sw. is an evergreen shrub widely distributed in Cuba and throughout the Caribbean region. In spite of its extended traditional use as antiasthmatic and antimicrobial by the local population, scientific reports on the species are almost nonexistent. This paper focuses on the isolation and characterization of compounds present in the crude extract of E. lucida Sw. leaves through the combined use of chromatographic and spectroscopic techniques (medium pressure liquid chromatography, thin-layer chromatography, gas chromatography, nuclear magnetic resonance 1H, and mass spectrometry). A total of 15 nonpolar substances were identified in the four main fractions obtained; some of these substances could be related with the antimicrobial properties attributed to the species.
Authors:Q. Bui, J. Sherma, B. Fried, and J.K. Hines
Prions of the baker’s yeast Saccharomyces cerevisiae allow for the inheritance of complex traits based solely on the acquisition of cytoplasmic protein aggregates and confer distinctive phenotypes to the cells which harbor them, creating heterogeneity within an otherwise clonal cell population. These phenotypes typically arise from a loss-of-function of the prion-forming protein that is unable to perform its normal cellular function( s) while sequestered in prion amyloid aggregates, but the specific biochemical consequences of prion infection are poorly understood. To begin to address this issue, we initiated a direct investigation into the potential control that yeast prions exert over fungal lipid content by utilizing the prions [URE3] and [PSI+], the first two prions discovered in yeast. We utilized silica gel high-performance thin-layer chromatography (HPTLC)—densitometry to conduct pair-wise quantifications of the relative levels of free sterols, free fatty acids, and triacylglycerols [petroleum ether—diethyl ether—acetic acid (80:20:1) mobile phase, phosphomolybdic acid (PMA) detection reagent]; steryl esters and squalene (hexane—petroleum ether—diethyl ether—acetic acid (50:20;5:1), PMA]; and phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol (chloroform– diethyl ether—acetic acid (65:25:4.5), cupric sulfate—phosphoric acid) in otherwise clonal prion-infected ([PSI+] or [URE3]) and prion-free ([psi−] or [ure-o]) cells in two growth phases: log-phase and stationary phase. Our analysis revealed multiple statistically significant differences (p < 0.00625) between prion-infected and prion-free cells. Interestingly, prion-induced changes varied dramatically by growth phase, indicating that prions exert differential influences on cell physiology between log and stationary growth. Further experimental replication and extension of the analysis to other prions is expected to resolve additional physiological effects of prion infection. This investigation demonstrates that HPTLC—densitometry is an effective method for studying prion-induced alterations in lipid content in yeast.
Mulliken overlap populations of the clusters with the adsorbates were employed to determine the crystal orbital overlap population (COOP) [ 58 ]. DOS and COOP spectra were plotted using Gaussian curves with the full width at half-minimum arbitrarily equal
Authors:K. Alloun, O. Benchabane, M. Hazzit, F. Mouhouche, A. Baaliouamer, A. Chikhoune, and A. Benchabane
Northern Algeria is widely used by local population as food additive and in Algerian folk medicine for its antitussive, antiseptic, expectorant, anti-helmintic, and anti-spasmodic properties [ 3 ].
The herbal plant, like other production, can be
Authors:Samiuela Lee, Christa E. Nath, Ben W. R. Balzer, Craig R. Lewis, Toby N. Trahair, Antoinette C. Anazodo, and Peter J. Shaw
later confirmed in a population pharmacokinetic analysis [ 3 ] and in a recent exposure–response analysis that was conducted in 225 adults with ALK-positive non-small-cell lung cancer in which steady-state trough concentration was used as the clinically
Authors:Akifumi Eguchi, Takeshi Enomoto, Norimichi Suzuki, Miho Okuno, and Chisato Mori
of PCBs. However, sample size was insufficient, and further investigation is required to assess the exposure of the Japanese population to PCBs.
These studies were supported by grants for
), occupy a large share of the pharmaceutical market due to the increase in the elderly population, many of whom have hypertension. BBs are competitive antagonists at β-adrenergic receptor sites and are used to treat cardiovascular disorders, such as