Nadja B. Cech

**Expertise: Analytical Chemistry, Mass Spectrometry, Medicinal Plant Chemistry **Education: B.S., Southern Oregon University, 1997--Ph.D., The University of New Mexico, 2001

There are 26 included publications by Nadja B. Cech :

TitleDateViewsBrief Description
Alkaloid Variation Among Epichloid Endophytes of Sleepygrass (Achnatherum robustum) and Consequences for Resistance to Insect Herbivores 2014 39 Epichloid endophytes are well known symbionts of many cool-season grasses that may alleviate environmental stresses for their hosts. For example, endophytes produce alkaloid compounds that may be toxic to invertebrate or vertebrate herbivores. Achnat...
Antimycobacterial Furofuran Lignans from the Roots of Anemopsis californica 2014 169 Topical preparations of Anemopsis californica have been used by Native American tribes in the southwestern United States and northern Mexico to treat inflammation and infections. We report results of bioassay-guided isolation conducted on a sample of...
CodY-Mediated Regulation of the Staphylococcus aureus Agr System Integrates Nutritional and Population Density Signals 2014 337 The Staphylococcus aureus Agr system regulates virulence gene expression by responding to cell population density (quorum sensing). When an extracellular peptide signal (AIP-III in strain UAMS-1, used for these experiments) reaches a concentration th...
Comparison of alkylamide yield in ethanolic extracts prepared from fresh versus dry Echinacea purpurea utilizing HPLC–ESI-MS 2009 251 Echinacea purpurea (L.) Moench, a top selling botanical medicine, is currently of considerable interest due to immunomodulatory, anti-inflammatory, antiviral and cannabinoid receptor 2 (CB2) binding activities of its alkylamide constituents. The purp...
Echinacea alkylamides inhibit interleukin-2 production by Jurkat T cells 2006 333 Alkylamides present in Echinacea species have reported immunomodulatory actions, yet their direct effects on T lymphocytes, key mediators of antiviral immunity, are poorly understood. We hypothesized that constituents present in ethanolic extracts of...
Echinacea and its alkylamides: Effects on the influenza A-induced secretion of cytokines, chemokines, and PGE2 from RAW 264.7 macrophage-like cells 2010 431 The goal of this study was to determine whether extracts and isolated alkylamides from Echinacea purpureawould be useful for prevention of the inflammatory response that accompanies infections with H1N1 influenza A. Seventeen extracts and 4 alkylamid...
Effects of herbal products and their constituents on human cytochrome P4502E1 activity 2007 565 Ethanolic extracts from fresh Echinacea purpurea and Spilanthes acmella and dried Hydrastis canadensis were examined with regard to their ability to inhibit cytochrome P4502E1 mediated oxidation of p-nitrophenol in vitro. In addition, individual cons...
Ethanolic Echinacea purpurea Extracts Contain a Mixture of Cytokine-Suppressive and Cytokine-Inducing Compounds, Including Some That Originate from Endophytic Bacteria 2015 219 Echinacea preparations, which are used for the prevention and treatment of upper respiratory infections, account for 10% of the dietary supplement market in the U.S., with sales totaling more than $100 million annually. In an attempt to shed light on...
Flavonolignans from Aspergillus iizukae, a Fungal Endophyte of Milk Thistle (Silybum marianum) 2014 98 Silybin A (1), silybin B (2), and isosilybin A (3), three of the seven flavonolignans that constitute silymarin, an extract of the fruits of milk thistle (Silybum marianum), were detected for the first time from a fungal endophyte, Aspergillus iizuka...
Goldenseal (Hydrastis canadensis L.) Extracts Synergistically Enhance the Antibacterial Activity of Berberine via Efflux Pump Inhibition 2010 266 Goldenseal (Hydrastis canadensis L.) is used to combat inflammation and infection. Its antibacterial activity in vitro has been attributed to its alkaloids, the most abundant of which is berberine. The goal of these studies was to compare the composi...
High performance liquid chromatography/electrospray ionization mass spectrometry for simultaneous analysis of alkamides and caffeic acid derivatives from Echinacea purpurea extracts 2006 405 Extracts of the plant Echinacea purpurea are widely used for medicinal purposes. Effective quality control of these extracts requires rapid methods to determine their chemical composition. A new method for analysis of caffeic acid derivatives and alk...
Inhibition of H1N1 influenza A virus growth and induction of inflammatory mediators by the isoquinoline alkaloid berberine and extracts of goldenseal (Hydrastis canadensis) 2011 413 In this study we tested whether the isoquinoline alkaloid berberine can inhibit the growth of influenza A. Our experiments showed strong inhibition of the growth of H1N1 influenza A strains PR/8/34 or WS/33 in RAW 264.7 macrophage-like cells, A549 hu...
Liver Enzyme-Mediated Oxidation of Echinacea purpurea Alkylamides: Production of Novel Metabolites and Changes in Immunomodulatory Activity 2006 1098 The medicinal plant Echinacea is widely used to treat upper respiratory infections and is reported to stimulate the human immune system. A major constituent class of Echinacea, the alkyl-amides, has immunomodulatory effects. Recent studies show that ...
Maplexins, new a-glucosidase inhibitors from red maple (Acer rubrum) stems 2012 233 Thirteen gallic acid derivatives including five new gallotannins, named maplexins A–E, were isolated from red maple (Acer rubrum) stems. The compounds were identified by spectral analyses. The maplexins varied in number and location of galloyl groups...
A Mass Spectrometry-Based Assay for Improved Quantitative Measurements of Efflux Pump Inhibition 2015 290 Bacterial efflux pumps are active transport proteins responsible for resistance to selectedbiocides and antibiotics. It has been shown that production of efflux pumps is up-regulatedin a number of highly pathogenic bacteria, including methicillin res...
Polyhydroxyanthraquinones as Quorum Sensing Inhibitors from the Guttates of Penicillium restrictum and Their Analysis by Desorption Electrospray Ionization Mass Spectrometry 2014 144 The endophytic fungus Penicillium restrictum was isolated from the stems of a milk thistle (Silybum marianum) plant. In culture, the fungus produced distinct red guttates, which have been virtually uninvestigated, particularly from the standpoint of ...
Quantitative analysis of autoinducing peptide I (AIP-I) from Staphylococcus aureus cultures using ultrahigh performance liquid chromatography–high resolving power mass spectrometry 2013 147 Staphylococcus aureus infections acquired in hospitals now cause more deaths per annum in the US than does HIV/AIDS. Perhaps even more alarming is the rise in community associated methicillin-resistant S. aureus (CA-MRSA) infections, which have sprea...
Quorum Quenching and Antimicrobial Activity of Goldenseal (Hydrastis canadensis) against Methicillin-Resistant Staphylococcus aureus (MRSA) 2012 994 The popular herbal remedy goldenseal (Hydrastis canadensis L.) is traditionally used to treat skin infections. With this study, we show activity of H. canadensis extracts in vitro against methicillin-resistant Staphylococcus aureus (MRSA). An extract...
Rapid Quantitation of Furanocoumarins and Flavonoids in Grapefruit Juice using Ultra-Performance Liquid Chromatography 2013 502 Introduction:Grapefruit juice can increase or decrease the systemic exposure of myriad oral medications, leading to untoward effects or reduced efficacy. Furanocoumarins in grapefruit juice have been established as inhibitors of cytochrome P450 3A (C...
Relative Importance of Basicity in the Gas Phase and in Solution for Determining Selectivity in Electrospray Ionization Mass Spectrometry 2008 190 Electrospray ionization mass spectrometry is a critically important technique for the determination of small molecules, but its application for this purpose is complicated by its selectivity. For positive ion ESI-MS analysis of basic analytes, severa...
The relative influences of acidity and polarity on responsiveness of small organic molecules to analysis with negative ion electrospray ionization mass spectrometry (ESI-MS) 2005 212 The purpose of the work presented here was to evaluate the influence of solution composition and analyte characteristics on responsiveness to analysis with negative ion electrospray ionization mass spectrometry. The responses of a series of structura...
Sarothrin from Alkanna orientalis Is an Antimicrobial Agent and Efflux Pump Inhibitor 2013 125 An Alkanna orientalis leaf and flower extract inhibited the growth of Staphylococcus aureus, a pathogen that causes an estimated 478000 hospitalizations in the US annually. Bioassay-guided fractionation of A. orientalis resulted in isolation of the f...
Small-molecule quorum quenchers to prevent Staphylococcus aureus infection 2013 307 Antibiotic-resistant bacteria are one of the most significant current threats to human health. The diminishing antibiotic development pipeline coupled with the propensity for bacterial pathogens to evolve resistance represents an ongoing crisis that ...
Synergy-Directed Fractionation of Botanical Medicines: A Case Study with Goldenseal (Hydrastis canadensis) 2011 49 It is often argued that the efficacy of herbal medicines is a result of the combined action of multiple constituents that work synergistically or additively. Determining the bioactive constituents in these mixtures poses a significant challenge. We h...
Temperature-sensitive anthocyanin production in flowers of Plantago lanceolata 2007 2085 Flower color in the weedy perennial Plantago lanceolata is phenotypically plastic. Darker flowers are produced at cooler ambient temperatures, and circumstantial evidence suggests that this is adaptive. The goal of this project was to investigate the...
w-Hydroxyemodin Limits Staphylococcus aureus Quorum Sensing-Mediated Pathogenesis and Inflammation 2015 97 Antibiotic-resistant pathogens are a global health threat. Small molecules that inhibit bacterial virulence have been suggested as alternatives or adjuncts to conventional antibiotics, as they may limit pathogenesis and increase bacterial susceptibil...