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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Phytochemical and Antibacterial Analysis of Echinacea Purpurea (L.) Moench Throughout Seasonal Development

Daley, Elizabeth 07 February 2019 (has links)
Echinacea purpurea is consumed as a natural health product around the world. Due to the genus’ ethnobotanical relevance, the phytochemistry of Echinacea has been extensively studied, revealing a variety of bioactive metabolites including caffeic acid derivatives and alkylamides. Whereas seasonal trends in root chemistry have been established, trends in other plant parts are relatively understudied. Similarly, few studies have evaluated the effects of organic plant growth substances in field trials. With increased demand for organic products, industry is looking for alternative ways to optimize yields and medicinal properties. For this thesis, my first objective was to quantify the concentrations of E. purpurea’s secondary metabolites across organic treatments throughout the plant’s first growth year to determine optimal harvesting time and conditions in all parts of the plant. The second objective was to determine how seasonal variations affect its potential bioactivity through inhibition of Pseudomonas aeruginosa. Plants were grown in field plots treated with four different organic treatments: water (control), high cytokinin, low cytokinin, and fish oils; samples were collected biweekly from May-September. Dried plants were separated into major plant parts and were extracted exhaustively in 70% EtOH. Using high-pressure liquid chromatography (HPLC), concentrations of alkylamides and select caffeic acid derivatives were quantified in all samples and compared across plant part, developmental stage, and organic fertilizers. It was determined that while there were no major differences between treatments, phytochemical concentrations changed throughout the season in all plant parts; revealing that aerial parts of the plant also bioactive secondary metabolites and should not be excluded from future studies. Following this study, an MIC50 assay was used to test these extracts against P. aeruginosa PA14. It was noted that seasonality effects of phytochemistry were not consistent with bioactivity and that there were no significant differences between extract and carrier control. While the antibiotic activity of root extracts varied seasonally, the flower extract exhibited the most consistent antibiotic potential. The results presented in this thesis will not only aid in industry practices and yield optimization but, through filling knowledge gaps on seasonality and organic treatments in field trials, will increase the understanding of E. purpurea’s chemistry and related bioactivity, with implications on both the medicinal properties and eco-physiology of the species.
2

The reactions of Claviceps purpurea to variations of environment

McCrea, Adelia, January 1900 (has links)
Thesis (Ph. D.)--University of Michigan, 1930. / Cover title. "Reprinted from the American journal of botany, vol. XVIII, no. 1 ... January, 1931." "Literature cited": p. 76-78.
3

In vivo evaluation of immunomodulatory properties of crude extracts of Echinacea species and fractions isolated from Echinacea Purpurea

Spence, Katherine Marie January 2002 (has links)
This thesis describes the in vivo evaluation of orally administered extracts of Echinacea species, and fractions obtained from Echinacea purpurea for specific immunostimulatory function induced in Balb/c mice by immunization with microbial vaccines. Two vaccines were used for this purpose in this study. The first vaccine used consisted of whole-cell formalin-killed Salmonella typhimurium vaccine, which is known to induce production of specific antibodies but no delayed-type hypersensitivity response considered as an indicator of the cell-mediated immune response. The second vaccine was a commercial acellular pertussis vaccine (DTaP) consisting of inactivated diphtheria and tetanus toxoids and native or inactivated virulence factors of Bordetella pertussis (the etiological agent of whooping cough) which is known to induce a humoral immune response but with controversial reports about performance in the induction of cell-mediated immunity. Both vaccines were administered intraperitoneally, whereas the herbal extracts and fractions were administered by oral gavage. The phytochemical profile of the ethanolic extracts of Echinacea purpurea, Echinacea pallida, Echinacea angustifolia and one commercial product "Echinacea Triplex" and three fractions prepared from Echinacea purpurea, namely polysaccharides, phenolics and alkylamides, was determined by thin-layer chromatography, high-performance liquid chromatography and/or by chemical analytical techniques. Statistically significant increases in specific anti-Salmonella typhimurium serum antibody were obtained for the Echinacea purpurea, Echinacea angustifolia and Echinacea Triplex [Trade Mark] treatment groups, and also for groups receiving treatment with fractions obtained from Echinacea purpurea, namely, polysaccharide, alkylamide and phenolic fractions. Statistically significant increases in the anti-B pertussis serum antibodies were also obtained in the young Echinacea Triplex [Trade Mark] group vaccinated with the DTaP vaccine. Significant enhancement of serum interleukin-12 titres was observed in the Echinacea Triplex [Trade Mark] as well as the phenolic fraction treatment groups which were vaccinated with killed Salmonella typhimurium vaccine. Of the groups vaccinated with the DTaP vaccine, only Echinacea Triplex [Trade Mark] displayed statistically significant increases in mean interleukin-12 titre compared to the placebo in both young and old groups, however Echinacea purpurea, and Echinacea angustifolia both displayed significant increases in mean interleukin-12 titre in the young treatment mice. Increases in interferon-gamma levels in mice orally dosed with phenolic, polysaccharide or alkylamide fractions of Echinacea purpurea and vaccinated with the killed Salmonella typhimurium vaccine were also observed, however these need to be repeated for confirmation, and statistical analysis.
4

Ežiuolės (Echinacea Moench.) genties rūšių anatominės ir morfologinės sandaros savitumai / Anatomic and morfological structure singularity Echinacea (Echinacea Moench.) genus spieces

Atkočiūnaitė, Stasė 16 August 2007 (has links)
Nuo 2004 metų buvo pradėta tirti blyškiosios ežiuolės (Echinacea pallida (Nutt.) Nutt) anatominė ir morfologinė sandara, atlikti lapo, stiebo ir šaknies tyrimai. Tęsiant pradėtą darbą magistriniame darbe, tyrimo objektu buvo pasirinktos dvi (Echinacea Moench.) genties rūšys: blyškioji (Echinacea pallida (Nutt.) Nutt) ir rausvažiedė (Echinacea purpurea (L.) Moench.). Išanalizavus ežiuolės (Echinacea Moench.) genties rūšių vegetatyvinių organų anatominę sandarą, darbe pateikti išsamūs jų sandaros aprašymai, nurodomi anatominiai diagnostiniai požymiai bei kiekybiniai savitumai. Ištyrus blyškiosios (Echinacea pallida) ir rausvažiedės (Echinacea purpurea L.) ežiuolių vegetatyvinių organų anatominę sandarą visuose pavyzdžiuose nustatyta heterobatmija. Ežiuolės (Echinacea Moench.) lapuose didžiausią diagnostinę reikšmę turi žiotelinio aparato pagalbinių ląstelių skaičius ir išsidėstymas. Blyškiosios ežiuolės ( Echinacea pallida) lapalakščiui būdingas anomocitinis žiotelinio aparato tipas. Šio tipo žiotelinis aparatas apsuptas 3 pagalbinėmis ląstelėmis, viena iš kurių žymiai mažesnė už kitas dvi. Rausvažiedės ežiuolės (Echinacea purpurea L.) lapalakščiui būdingas anomocitinis žiotelinio aparato tipas. Tai toks žiotelinio aparato tipas, kai varstomosios ląstelės apsuptos nuo 2 iki 6 pagalbinių ląstelių, kurios nesiskiria nuo epidermio ląstelių nei dydžiu, nei forma. Tiriant ežiuolės (Echinacea Moench.) genties rūšių epidermio sandarą nustatyta, kad žiotelinis aparatas išsidėsto... [toliau žr. visą tekstą] / Anatomical characteristic of Echinacea Moench. genus species is presented in this work. Then are reseached there species of Echinacea Moench.: E. purpurea, E. palaida and E. angustifolia. The description and comparison of overgraund stems, leaves, rhizomes and roots anatomic structure of there species are presented in this work, also diagnostic characters and quantative characteristic are specified. After anglyzis of anatomical structure of Echinacea Moench axial organs it was established heterobatmia. By anatomical characters comparison exodermis structure in the stems is of great diagnostic `importance. Exodermis lamellosity is constant character. The number of auxiliary cells of stomatal aparatus and their situation are of great diagnostic importance in the leaves. E. purpurea leaf has anomacitical stomatal aparatus type. The means, stomatal guard cells are surrounded by from 2 to 6 auxilaliary celle, which doesn't differ from epidermis cells. E. pallida leaft has anisocitical atomatal aparatus type. The stomatal guard cells of this are surrounded then other. Striking differences are characteristic to the structure and situation of secretory tissue in the anglyzis of anatomical structure of Echinacea Moench rhizomes. All analyzed plants have schizogenic glands. Epitelium cells lamellosity and inner canal cavity in the schizogenic glanda are different in the different species of plants. One Echinacea Moench. is different from another in lamelloity of suber tissue in... [to full text]
5

A study on the effect of a homoeopathic complex formula consisting of Echinacea purpurea tincture, Echinacea angustifolia tincture, Bapstisia tinctoria tincture and Thuja occidentalis D1 on circulating leukocytes

Davey, Karen Lee 05 February 2014 (has links)
M.Tech. (Homoeopathy) / The purpose of this study is to determine the effect of the homoeopathic complex formula consisting of , Echinacea angustifolia tincture, Baptisia tinctoria tincture and Thuja occidentalis D1 on circulating leukocytes. These medicinal plants have immune enhancing properties and an effect on leukocytes. Leukocytes play an important role in the body's defence system. 54 volunteers participated in a randomised double blind placebo controlled trial. An initial full blood count before treatment served as a base-line control for each volunteer. A total of 15ml of the medication placebo was administered over 3 hours. After the last dose, a further three blood samples were drawn at 90 minute intervals. Blood analysis included a differential leukocyte count. The trial was conducted over a single 6 hour period. The homoeopathic medication caused a decrease in circulating leukocytes, specifically lymphocytes. The efficacy of this medicationas an immunostimulant should be confirmed on a larger study sample.
6

Echinacea purpurea vid symtomlindring av akuta luftvägsinfektioner : Har Echinaforce® och extrakt av Echinacea purpurea effekt vid behandling av hosta och feber under influensa A?

Smrkovic, Amina January 2023 (has links)
Bakgrund Influensa är en akut respiratorisk infektion som orsakas av ett negativt RNA-virus. Insjuknade i influensa sker ofta under vintertid. Influensa finns i fyra olika typer, A-D. A är den vanligaste sorten under influensasäsong och påverkar både människor och djur, medan D påverkar främst grisar och nötkreatur. Influensa kännetecknas av att det börjar med en frossa och med en snabbt stigande feber (över 40℃) samt med muskelvärk och med en märkbar sjukdomskänsla. Efteråt sprids infektionen till luftvägarna, där det uppkommer symtom i form av torrhosta. Influensa sprids genom luftburna aerosoler eller genom dropp- och kontaktsmitta. Influensaviruset tar sig in i cellen via sina ytproteiner hemagglutinin (HA) och neuraminidas (NA) och sedan tar det sig in till värdcellens kärna, vilket leder till replikation av viruset. Vid influensasäsongen ges vaccinationer till personer som är över 65 år, och till är gravida och till personer som har någon underliggande kronisk sjukdom. Detta görs för att förhindra allvarlig sjukdom och för att kunna minska antalet komplikationer och dödsfall under influensasäsongen. Neuraminidashämmare som exempelvis oseltamivir och zanamivir kan ges för smärtlindring under influensan i fem dagar. Växten Echinacea purpurea och dess extrakt används som behandling av luftvägsinfektioner exempelvis hosta och vid inflammatoriska tillstånd, som exempelvis bronkit. Studier på olika extrakt av Echinacea purpurea har visat ökade halter av cytokiner som exempelvis TNF-α, IL-1 och IFN- β. Det har även visat en ökad aktivitet av fagocyterna och makrofager. En ökad mobilitet har också setts hos både leukocyter och aktivering av NK-celler. Syfte Syftet med arbetet var att undersöka om Echinacea purpurea har en symtomlindrande effekt på influensa A, speciellt på symtom som feber och hosta. Metod Publicerade vetenskapliga artiklar söktes i databasen Pubmed och OneSearch. Sökorden för artiklarna var “Influenza AND Echinacea purpurea” eller “Echinacea AND flu” I OneSearch användes sökorden “Influenza AND Echinacea purpurea”.ResultatStudierna visar att symtomen hosta och feber reducerades vid användning av Echinacea purpurea extrakt under behandling av influensa A. Behandlingen med Echinacea purpurea hade en bättre verkan vid användningen av en högre dos av extraktet (2000 mg) och om det användes några dagar innan influensasymtom uppträdde eller vid början av influensasymtom. Slutsats Utifrån de publicerade resultaten av de fyra studierna verkar Echinacea purpurea ha en mildrande effekt på hosta och feber under akuta luftvägsinfektioner. Det visade att dosen som hade mest effekt i dessa studier, var 2000 mg av växtextrakt från Echinacea purpurea. Dessa resultat erhölls vid behandling av i övrigt friskaindivider som endast hade förkylningssymtom eller influensasymtom, vilket gör att Echinacea purpurea extrakt kan ha andra effekter om det används på kroniskt sjuka individer. Flera äldre vaccinerar sig mot influensa, vilket gör att Echinacea purpurea extrakt har mer gynnsam effekt på yngre personer som har drabbats av influensa t.ex. barn eller unga vuxna. / Background Influenza is an acute respiratory infection which is caused by a negative stranded RNA-virus. Infection usually happens during the winter season. There are four different types of influenza, A-D. Type A is the most common one and affects both humans and animals, while type D has only been detected in pigs and cattle. Influenza starts with chills with a quickly rising fever (over 40℃) together with muscle pains. Afterwards the infection spreads to the airways, where the symptoms of dry cough arise. Influenzaspreads through airborne aerosols or through contact. The influenza virus enters the hostcell through the surface proteins HA and NA, while later entering the nucleus where the replication of the virus occurs. Before the flu season begins, people over the age of 65, pregnant women and patients with a chronic disease are vaccinated. This is done to prevent serious diseases that may occur during the flu and to lower the rate of secondary infections and also to prevent death. Medications such as oseltamivir and zanamivir can be given to treat the infection; however, they are mostly used to relieve symptoms. Echinacea purpurea is a traditionally used medicinal plant which has been used to treat respiratory tract infections like respiratory infections and inflammatory conditions such as bronchitis. Studies on different extracts of Echinacea purpurea have shown that they increase levels of TNF-ɑ, IL-1 and IFN-β as well as an increase of macrophages and other phagocytes after treatment with Echinacea extract. Similarly, the extract has shown an increased mobility of leukocytes and activation of Natural Killer-cells. Aim The aim of this study was to examine if treatment with medications containing extracts of Echinacea purpurea relieved symptoms such as, cough and fever, when used in the treatment of influenza A. Method The previously published articles were searched for by using the databases Pubmed and OneSearch. The words used in the search for published articles were “Influenza AND Echinacea purpurea” or ”Echinacea AND flu” in Pubmed. In the database, OneSearch the words “Influenza AND Echinacea purpurea'' were used. Results The selected studies showed that the symptoms such as cough and fever, were reduced in studied patients that used Echinacea purpurea extracts during the treatment of influenza A. Infection was verified through nasal swabs that then were screened. The results showed that the treatment was more effective when using a dose of 2000 mg of Echinacea purpurea extract. Moreover the treatment was effective when used a few days before symptoms occurred or at the beginning of a respiratory tract infection. Conclusion The results from the four studies suggested that the extract from Echinacea purpureareduces cough and fever during acute respiratory infections. The dosage of 2000 mg Echinacea purpurea extract had the most effect. However the extracts were tested on healthy people that only had common cold symptoms or influenza symptoms, thus different results could have been obtained if the effects were tested on unhealthy individuals.
7

Optimization and investigation of Echinacea tablets with "basis granulate" technology / Optimisation et investigation de comprimés d'Echinacea en utilisant la technologie de "granulés de base"

Qusaj, Ylber 01 February 2013 (has links)
La fabrication d’un médicament sous forme de comprimés à base d'une plante fraîche reste actuellement encore un véritable enjeu et ce, à cause de la variabilité qui peut exister dans les différents lots d'extraits de plantes ainsi qu’à la limite imposée par les techniques de fabrication de comprimés existantes actuellement. Différents problèmes rencontrés avec la formulation actuelle de ce type de comprimés ont été observés tels que : les propriétés physiques du comprimé (très faible dureté des comprimés et temps de désagrégation assez long), goût désagréable, grande variabilité (variabilité de l'extrait sec) et mauvaise stabilité de la substance médicamenteuse. Des observations antérieures ont indiqué que la stabilité de la substance médicamenteuse dans les comprimés d'Echinacea purpurea ainsi que le goût peuvent être améliorés en la mélangeant avec de la bêta-cyclodextrine (β-CD). Dans la thèse de doctorat, une formulation actuelle commercialisée de comprimés d’Echinacea purpurea a été réalisée par la technique de la granulation par voie humide, avec un mélangeur à cisaillement élevé. Dans la formulation, presque la totalité de l'excipient (lactose monohydraté) est mouillé par le concentré d'Echinacea purpurea. Afin de réduire la quantité d'excipients à granuler et à sécher et d’obtenir un produit avec moins cher des couts de matériaux premières, un procédé de granulation classique a été proposé où seulement une fraction de la quantité totale de charge (cellulose microcristalline (MCC)) est utilisée pour la granulation et le séchage; le reste de la charge (sorbitol) est ajouté après la granulation. Ce granulat peut servir de matériau de base des différents comprimés. Dans les différentes expérimentations réalisées, la teinture d’Echinacea purpurea a été utilisée comme modèle pour l'optimisation de la fabrication des comprimés à base de plantes. L'objectif de la thèse était par conséquent de développer une nouvelle formulation de comprimés d’Echinacea purpurea en utilisant un procédé de granulation classique. Avec une meilleure maîtrise de la granulation humide (WGP) et son influence sur les propriétés physiques des comprimés, ceux-ci doivent être optimisés du point du vue de la stabilité de l'ingrédient actif qui se présente sous forme solide (alkylamides) et des propriétés physiques des comprimés, en particulier le taux de dissolution et les propriétés physiques des comprimés. / One current formulation of Echinacea tablets which is examined in the present thesis is to produce tablets in a wet granulation process (WGP) with a high shear mixer. During the manufacturing, almost the whole amount of the excipient (lactose monohydrate) is wetted by Echinacea purpurea concentrate. In order to reduce the amount of excipients being granulated and dried by a basis granulate method was proposed where only a fraction of the total amount of filler (Microcrystalline cellulose, MCC) is used for granulation and drying, the rest of the filler (sorbitol) is added after granulation. This granulate can serve as basis material for different tablets.Purpose: in the PhD thesis, tablets containing Echinacea purpurea tincture were used as a model for the optimization of herbal tablets. The aim of the dissertation was to develop a new Echinaforce formulation based on the “Basis Granulate” technology. With deeper understanding of the WGP and its influence on the physical tablet properties, the new Echinaforce tablets should be optimized in term of cost of goods, taste of tablets, stability of the active ingredient in solid forms (alkylamides) and the physical tablet properties of Echinaforce tablets, especially the dissolution rate and the compaction properties of the final tablet.
8

Evaluating disease reaction of western Canadian spring wheat cultivars (Triticum spp.) to natural and artificial infection with Claviceps purpurea (Fr.) Tul.

2013 June 1900 (has links)
Ergot, caused by the fungal pathogen Claviceps purpurea (Fr.) Tul., attacks the floral organs of many grassy species resulting in sclerotia production rather than grain. Infection causes reduced yields, downgrading, and poisoning if consumed by humans or animals. Few recent studies have been conducted on ergot in wheat (Triticum spp.), and prevention is the only means of control. The objectives of this study were to determine if western Canadian spring wheat differed in reaction to infection with C. purpurea and if levels of inoculum would affect disease intensity in a field setting. Three variables were measured for the field experiments to determine disease reaction, including percent sclerotia by weight, number of sclerotia per spike, and weight per sclerotium. In the first experiment, nine wheat cultivars were tested using three inoculum levels. No significant differences were detected among inoculum levels. In the second and third experiments, ninety-two cultivars were studied in field and controlled conditions. Honeydew production, sclerotial size, and the percent of florets aborted were added as variables in the growth chamber experiment. Pearson correlations were calculated using cultivar means for the field and controlled environments. Results indicate that there are differences in disease reaction among cultivars and market classes, but these differences varied depending on the evaluation method used. In the field, CWAD wheat had the smallest sclerotia, but had more per spike compared to the CWRS and CWES market classes. There were no significant differences among these market classes for percent sclerotia by weight. In the growth chamber, CWAD wheat generally had the lowest ergot infection levels. When comparing the market classes within T. aestivum (CWRS, CPS, and CWES), there were no significant differences except for honeydew production. The correlation between environments was not significant for any of the variables, suggesting alternate resistance mechanism expression. In the field, reduced infection may be due to an escape mechanism, while artificial inoculation in a controlled environment may detect a physiological resistance mechanism. However, a group of cultivars with Grandin parentage showed promising results in both environments, and might confer resistance that could be integrated into disease resistance breeding programs.
9

Bioremediation of Contaminated Soils by Echinacea purpurea and Arbuscular Mycorrhizal Fungi

Pretorius, Travers January 2015 (has links)
As a potential bioremediation system for contaminated soils, I evaluated the use of an arbuscular mycorrhizal (AM) fungus, Glomus intraradices on roots and shoots uptake of polycyclic aromatic hydrocarbons (PAHs), alkyl PAHs, and toxic metals in Echinacea purpurea, in using a controlled 20-week greenhouse study and a complimentary 2-year field study. E. purpurea seeds were either inoculated with the mycorrhizal fungus (AM) or not inoculated (non-AM) and grown in soil provided by the National Capital Commission (NCC) that have known contamination. In the greenhouse study, AM inoculation increased the uptake of alkyl PAHs in the roots of E. purpurea. The AM inoculation showed no effect on root uptake of PAHs and toxic metals over the 20-week study period. However, when I calculated the uptake rates (k1) for PAHs between both treatments, the AM treated roots ha 10-fold higher k1 values than non-AM treated roots. The soil concentrations of PAHs were found to increase over time with AM inoculation, suggesting, that AM fungi are causing a solvent depletion through root uptake of minerals and carbon, which concentrates the more hydrophobic PAHs in soils. Alkyl PAHs and metals showed no change over time amongst any of the treatments. Assessing the performance of AM fungi on the uptake of contaminants under field conditions, only PAHs showed increased bioaccumulation in the shoots of E. purpurea with AM inoculation. Alkyl PAHs and metals in plant material were unaffected by the AM inoculation, but increased significantly from year 1 to year 2. The uptake rates among treatments were similar, with non-AM roots having slightly greater uptake. Soil concentrations of PAHs and alkyl PAHs were unaffected over the course of the experiment. Our control soil, however, showed significant increases in concentration from year 1 to year 2 with alkyl PAHs. These results quantified the influence of AM hyphae-mediated uptake of organic and inorganic contaminant transfer from soil to plants and the bioaccumulation kinetics for contaminants by E. purpurea that will be useful for environmental models and phytoremediation strategies.
10

Understanding the evolutionary potential of weeds: Baker’s weediness traits, tolerance to competition, and the general purpose genotype

Chaney, Lindsay 17 October 2014 (has links)
No description available.

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