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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

The effects of nitrogen on the chemical composition of yarrow (Achillea millefolium L. complex) /

Russell, Fiona E. 01 January 2001 (has links) (PDF)
No description available.
2

An improved isolation method for achilleine, an alkaloid from Achillea millefolium linne

Landers, Roy March, 1934- January 1958 (has links)
No description available.
3

In vivo, in vitro micropropagation and chemical characterisation of medicinal compounds in chamomile and yarrow species (Asteraceae)

Mahmood, Banaz January 2018 (has links)
The Asteraceae family is frequently used to describe several medicinal plants which contain various phytochemical compounds including phenols, flavonoids and terpenoids. Among the Asteraceae family German chamomile (Matricaria chamomilla L.) and yarrow (Achillea millefolium L.) plants are extant species used in contemporary medicine. These phytochemical compounds have been traditionally used since ancient times in health care systems worldwide as a source of medicines. The use of micropropagation is essential to improve and increase these active compounds via plant tissue culture within a short period of time using the application of key plant growth regulators (PGRs). Furthermore, quantitative and qualitative analysis using high performance liquid chromatography- ultraviolet detector (HPLC-UV) and gas chromatography- flame ionisation detector (GC-FID) of potential medicinal compounds expressed by both chamomile and yarrow are important points. The protocol of in vitro shoots, roots and callus formation of chamomile and yarrow seeds culture were investigated using Murashige and Skoog (MS) medium supplemented with different concentrations of plant growth regulators (PGRs). MS culture medium containing 0.5 mgL-1 IAA and 1.0 mgL-1 of GA3 were found to be the best culture medium for chamomile and yarrow seeds. In this project in vitro and in vivo growth rates of selected plant species were also investigated. In the earlier growth stages yarrow plants were found to grow much quicker than chamomile, while the yield of chamomile flowers was significantly (p ≤ 0.001) more than yarrow flowers. The phenolic, flavonoid and terpenoid compounds content of leaves and flowers of plants produced from both cultures were also studied. HPLC-UV analysis showed that chlorogenic acid, apigenin-7-O-glucoside and luteolin dominated as the main phenol and flavonoid compounds recovered in both in vitro and in vivo chamomile and yarrow cultures. However, GC-FID analysis indicated that farnesene and nerolidol were detected as the main terpenoid compounds present in the two culture conditions used to grow chamomile and yarrow plants. Moreover, this research examines how chamomile and yarrow plants can produce and improve their phytochemical compounds content not only under well-watered conditions but also under drought stress conditions. The main phenol and flavonoid compounds of chlorogenic acid, caffeic acid, apig-7-glucoside, umbelliferon and luteolin were found in chamomile and yarrow varieties grown under both well-watered and drought stress conditions using (HPLC-UV), however farnesene, nerolidol, chamazulene, α-(-)- bisabol and bisabolol oxide A were observed in the plant essential oils (EOs) using Soxhlet extraction and GC-FID analysis. The antibacterial activity of plant EOs was also investigated using disc diffusion and 96 well plates. In vivo chamomile EO showed the highest antibacterial activity against gram-positive and gram-negative bacteria strains. In addition, in vitro yarrow EO showed the greatest effect on the death of bacteria strains.
4

The edaphic ecology of two western North American composite species /

Cooke, Sarah Spear. January 1994 (has links)
Thesis (Ph. D.)--University of Washington, 1994. / Vita. Includes bibliographical references (leaves [252]-272).
5

An Ethnobotanical, Pharmacological, and Phytochemical Analysis of Achillea millefolium L. by Parts

Kachura, Alexandra 30 November 2018 (has links)
This thesis investigated the pharmacology and phytochemistry of Achillea millefolium L. (yarrow) flowers, roots, stems, and leaves based on ethnobotanical reports in North America, with a focus on applications in a respiratory model. Seasonal changes in the phytochemical profile of yarrow were also assessed. A comprehensive dataset of medicinal Asteraceae was created after collecting ethnobotanical reports from the Native American Ethnobotany (NAEB) database. Using residual and binomial analyses, 14 tribes of Asteraceae were quantitatively evaluated and ranked within ten therapeutic categories as either over- or under-selected for treatment by North American indigenous peoples. Flora belonging to the Anthemideae tribe were over-utilized as pulmonary aids, particularly species of Achillea. Yarrow was selected for further analysis in the subsequent chapters of this thesis. The respiratory pharmacology of yarrow was examined by testing the immunomodulatory effects of four plant parts in an in vitro assay using BEAS-2B human bronchial epithelial cells. Concentrations of the pro-inflammatory cytokines IL-6 and IL-8 were quantified using ELISA kits. Flowers demonstrated significant anti-inflammatory activity at 40 μg/ml in both assays, and also at 20 μg/ml in the IL-8 assay, suggesting a dose-dependent response. Roots displayed significant pro-inflammatory activity at all concentrations. A second mechanism of action via the endocannabinoid system was tested through inhibitory enzyme assays for fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), in which the flowers and roots were most active. Since extracts of the four plant parts exhibited significantly different bioactivities, active metabolites previously identified in yarrow were quantified in each part through the targeted profiling of phenolics and alkylamides using analytical chromatographic techniques. Phenolic compounds were found at highest concentrations in the flowerheads, while alkylamides were detected predominantly within roots. An accompanying phenological analysis of alkylamide and phenolic levels in all parts was explored. Collectively, this research provides the first integrated comparison of yarrow ethnobotany, bioactivity, and phytochemistry across different parts of the plant, contributing novel insights into the traditional, contemporary, and future uses of one of North America’s most important medicinal plants.
6

Determinação do perfil cromatográfico e avaliação da atividade do extrato etanólico de Achillea millefolium sobre Colletotrichum gloeosporioides / DETERMINATION OF CROMATOGRAPHIC PROFLE AND EVALUATION OF THE ACTIVITY OF EXTRACT ETHANOLIC Achillea millefolium ON Colletotrichum gloeosporioides

Duque, Fernanda Farias 27 February 2013 (has links)
Made available in DSpace on 2016-12-23T13:23:26Z (GMT). No. of bitstreams: 1 Fernanda Farias Duque.pdf: 807222 bytes, checksum: 0c1dd87b5f8f95ab1e7791bac3f4860c (MD5) Previous issue date: 2013-02-27 / A Achillea millefolium, conhecida como mil-folhas ou aquiléia, é uma planta da família Asteraceae e possui atividade como antibacteriana, antifúngica, antitumoral, cicatrizante, antioxidante e antiedematosa. O objetivo deste trabalho foi determinar o perfil cromatográfico e avaliar a atividade fungicida in vitro do extrato etanólico de A. millefolium sobre Colletotrichum gloeosporioides causador da antracnose em frutos de mamão. Partes da planta foram coletadas em dois meses diferentes e separadas em flores, folhas e ramos. Os bioensaios foram realizados com os extratos etanólicos secos, obtido por técnica de maceração e concentrado em evaporador rotativo sob pressão reduzida. Estes extratos foram submetidos a cromatografia preparativa em camada delgada (CCD) sendo obtidas cinco frações. Estas frações foram diluídas, separadamente, em 150μL de DMSO e incorporada em BDA. Após solidificação do meio, um disco de 0,6cm de diâmetro com o fungo foi colocado no centro da placa de petri e incubado a 28 ± 2°C. Após crescimento avaliou-se o crescimento radial do micélio. O delineamento experimental utilizado foi análise fatorial e as médias foram comparadas pelo teste de Tukey a 5% de probabilidade. A atividade antifúngica foi evidenciada contra C. gloeosporioides sendo que as frações F4 e F5 de folha e flor coletadas em outubro tiveram a maior porcentagem de inibição do crescimento micelial. O perfil cromatográfico das frações do extrato foi realizado através de analises utilizando HPLC-DAD e GC-MS. Através das análises utilizando HPLC e GC da folha coletada em outubro foi possível detectar a presença de ácido cumárico, ácido ferúlico e rutina nas frações F4 e F5 / The Achillea millefolium, known as mil-folhas or aquilea, is a plant of the Asteraceae family and possesses activity as antibacterial, antifungal, antitumor, healing, antioxidant and antiedematosa. The aim of this study was to determine the elution profile and evaluate the in vitro antifungal activity of the ethanol extract of A. millefolium on Colletotrichum gloeosporioides causing anthracnose on papaya fruits. Parts of the plant were collected in two different months and separated into flowers, leaves and branches. Bioassays were performed with dry ethanolic extracts obtained by maceration technique and concentrated in a rotary evaporator under reduced pressure. These extracts were subjected to preparative thin layer chromatography (TLC) was obtained five fractions. These fractions were diluted separately in 150μL of DMSO and incorporated in BDA. After solidification of the medium, a disc of 0.6 cm diameter with the fungus was placed in the center of a petri dish and incubated at 28 ± 2°C. After growth evaluated the radial growth of the mycelium. The experimental design was factorial analysis and the means were compared by Tukey test at 5% probability. The antifungal activity was observed against C. gloeosporioides whereas fractions F4 and F5 of leaf and flower collected in october had the highest percentage of mycelial growth inhibition. The chromatographic profile of the fractions of the extract was performed by analysis using HPLC-DAD and GC-MS. Through analysis using HPLC and GC leaf collected in october was possible to detect the presence of coumaric acid, ferulic acid and rutin in fractions F4 and F5
7

Atividade biológica e parâmetros bioquímicos e fisiológicos influenciados por fatores abióticos em Achillea millefolium L / Biological activity and biochemical and physiological parameters influenced by abiotic factors in Achillea millefolium L.

Lima, Milene Conceição 05 April 2013 (has links)
Made available in DSpace on 2014-08-20T13:59:06Z (GMT). No. of bitstreams: 1 tese_milene_conceicao_lima.pdf: 1117046 bytes, checksum: 61412e1bba4614df5d623d5245902770 (MD5) Previous issue date: 2013-04-05 / Several abiotic factors can coordinate or alter metabolic processes of growth and development plants such light, temperature, water availability, climate, soil nutrition and inorganic compounds. The objective of this study was to evaluate performance of A. millefolium L. (yarrow) against abiotic factors. To achieve this objective were have conducted two experiments in which the first was observed antimicrobial activity in vitro and essential oil yield of yarrow grown with nitrogen levels (0, 75 and 150 kg urea ha-1) and subjected different levels of shading 0% (full light) and 70% (70% shading). The second experiment were observed growth characteristics, production photosynthetic pigments, antioxidant enzymes activity, concentrations hydrogen peroxide, malondialdehyde, ascorbate and deidroascorbato, antioxidant activity by method DPPH and secondary metabolites synthesis in yarrow cultivated under light conditions (full light and blue, red and black shade net) and subjected different collection periods (eight weeks shading, two and four weeks after shading). The results show that oil yield extracted from flowers was stimulated by medium nitrogen level and full light increased the oil yield extracted from leaves. The highest essential oil yield was observed in reproductive structures. Antimicrobial activity of oil was confirmed against microorganisms species. Yeast strains were inhibited by the lowest concentration. The dry mass of leaves and flowers was favored in plants grown under full light. The content of chlorophyll a and b were higher in plants cultivated under blue net, total chlorophyll content was lower in plants under full light and plants two weeks after shading was increase of chlorophyll a, b and total, equivalent did not shaded plants. Catalase activity increased plants acclimated to high light intensity and low light did not stimulate ascorbate peroxidase, but increased superoxide dismutase and content of hydrogen peroxide. Lipid peroxidation was reduced presence of the spectrum blue and red light and low light intensity generated by nets black and blue, reduced accumulation of ascorbate. Content of deidroascorbato increased acclimation process to sunlight and antioxidant activity was more pronounced extracts of flowers. Levels total phenols and flavonoids were stimulated by full light. Oil yield extracted from flowers was higher than leaves. Major metabolite oil extracted from leaves was farnesol and flowers were farnesol and chamazulene. Results for medicinal species A. millefolium L. indicated that light intensity, light quality, collection periods and nitrogen fertilization influence growth, photosynthetic pigments production, secondary metabolites and antioxidant response. / Diversos fatores abióticos podem coordenar ou alterar os processos metabólicos de crescimento e desenvolvimento em plantas como a luz, temperatura, disponibilidade hídrica, clima, nutrição do solo e compostos inorgânicos. O objetivo deste estudo foi avaliar o comportamento de A. millefolium L. (mil-folhas) frente aos fatores abióticos. Para atingir este objetivo foram realizados dois experimentos, na qual no primeiro foi verificada a atividade antimicrobiana in vitro e rendimento do óleo essencial de mil-folhas cultivada com concentrações de nitrogênio (0, 75 e 150 Kg ureia ha-1) e submetida a diferentes níveis de sombreamento 0% (luz plena) e 70% (sombreamento 70%). No segundo experimento foram avaliadas características de crescimento, produção de pigmentos fotossintéticos, atividade de enzimas antioxidantes, teores de peróxido de hidrogênio, malondialdeído, ascorbato e deidroascorbato, atividade antioxidante pelo método DPPH e síntese de metabólitos secundários em mil-folhas cultivada sob condições de luminosidade (luz plena e sombreamento com malha azul, vermelha e preta) e submetida a diferentes períodos de coleta (oito semanas de sombreamento, duas e quatro semanas após o sombreamento). Os principais resultados mostram que o rendimento do óleo extraído de flores foi estimulado pela concentração nitrogenada intermediária e o extraído de folhas foi favorecido pela luz plena, sendo maior nas estruturas reprodutivas. A atividade antimicrobiana do óleo foi confirmada frente aos microrganismos, sendo as cepas fúngicas inibidas pela menor concentração. A massa seca das folhas e flores foi favorecida nas plantas cultivadas com luz plena. Os teores de clorofila a e b foram maiores nas plantas cultivadas com a malha azul, o conteúdo de clorofila total foi menor nas plantas sob luz plena e em plantas com duas semanas após o sombreamento ocorreu um incremento de clorofila a, b e total, equivalendo-se às plantas não sombreadas. A atividade da catalase aumentou em plantas aclimatadas em alta intensidade de luz e a baixa luminosidade não estimulou a ascorbato peroxidase, mas incrementou a superóxido dismutase e o teor de peróxido de hidrogênio. A peroxidação lipídica foi reduzida na presença dos espectros de luz azul e vermelha e a baixa intensidade de luz, gerada pelas malhas preta e azul, reduziu o acúmulo de ascorbato. O conteúdo de deidroascorbato aumentou em processo de aclimatação à luz solar e a atividade antioxidante foi mais acentuada em extratos de flores. Os teores de fenois e flavonoides totais foram estimulados pela luz plena. O rendimento do óleo extraído de flores foi maior em relação ao de folhas. O metabólito majoritário do óleo extraído de folhas foi o farnesol e os extraídos de flores foram o farnesol e camazuleno. Os resultados encontrados para a espécie medicinal A. millefolium L. indicaram que a intensidade luminosa, qualidade de luz, períodos de coleta e fertilização nitrogenada influenciam no crescimento, produção de pigmentos fotossintéticos, de metabólitos secundários e resposta antioxidante.
8

Multifaceted effects of competition and plant-soil feedbacks on Achillea millefolium grown in soil from a riparian meadow : Emil Karlsson - Umeå University - Thesis project - 60 hp

Karlsson, Emil January 2021 (has links)
Competition between plant individuals and how plants alter soil properties are key processes which drive changes in plant communities over time. Estimating the relative importance of these processes and how they affect plant growth in different ecological contexts and communities is an active area of research. Furthermore, interdependencies between the two processes have been suggested to occur in many cases, but research in this area is also lacking. In this study, soil conditioned by common yarrow (Achillea millefolium) was collected from field plots and was then used in a growth chamber competition experiment, which controlled for plant-soil feedbacks. Measured soil properties such as soil pH, soil nitrogen, and soil texture were primarily used as background data in the experiment. Field parameters such as light availability, plant density, and grass to forbs ratio were used to predict optimal A. millefolium habitat in relation to other vascular plant species. The results indicate that A. millefolium was a weaker competitor than cornflower (Centaurea cyanus), while a positive plant-soil feedback effect was observed by A. millefolium grown in field soil. Intraspecific competition had a strong negative effect on A. millefolium growth when grown in non-conditioned soil, but not when grown in A. millefolium conditioned soil. Finally, competition and plant-soil feedbacks appeared to be additively affecting A. millefolium growth, meaning the plant-soil feedback effect did not have a disproportionate effect on competitive outcomes, or vice versa. The findings of this study can be of interest to conservationists or farmers who wish to predict how plant communities respond to plant competition and plant-soil feedbacks as processes.
9

A study of the growth and development of yarrow (Achillea millefolium L.)

Bourdot, G. W. January 1980 (has links)
The response of yarrow (Achillea millefolium L.) seedlings to reduced light, interference from barley (Hordeum vulgare) and some aspects of regeneration from rhizomes were the subject of investigations from 1976 until 1980. Seedlings grown under four intensities of photosynthetically active radiation (100, 46.8, 23.7 and 6.4% of full summer daylight) were harvested on six occasions and the changes with time in the logarithms of leaf area, leaf, stem, root and total dry weights per plant were described by polynomial regression equations. Relative growth (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA) and leaf weight ratio (LWR) were derived directly from the growth curves. SLA and LWR increased with increased shading causing LAR to rise, while NAR declined. Response curves of RGR on light intensity, derived from linear regressions of LAR and NAR on the logarithm of relative light intensity predicted maximum RGR to occur at light intensities which decreased with time. This was a consequence of ontogenetic changes in LAR, and changes in NAR apparently related to self shading. Linear regressions of LAR and NAR at a constant total plant dry weight of 1.62 g showed that the increase in LAR almost completely compensated for the reduction in NAR down to approximately 40% full daylight, and maximum RGR was predicted to occur at 59% full daylight. The light compensation point was estimated to be 3.6% full daylight. Yarrow populations established from 25 and 50 10 cm rhizome fragments m⁻² were grown alone and with barley at 194 or 359 plants m⁻². The barley populations were also grown alone. Growth analysis employing the regression technique showed the RGR of yarrow was reduced by barley from before jointing (Feekes Scale, Stage 6) as a consequence of reduced NAR. The NAR of yarrow was significantly reduced in the continued presence of barely, which by the time of the final barely harvest resulted in 91 and 94% reduction in the accumulated yarrow dry matter at 194 and 359 barely plants m⁻² respectively. The proportion of total dry matter allocated to seed and rhizome was also reduced by barley but the barley was unaffected by the yarrow. During the autumn and early winter, after removal of the barley, the suppressed yarrow had a higher RGR than the unsuppressed population, owing to higher LAR and NAR. Rhizome growth was vigorous during both autumn and winter in all yarrow populations, but the RGR of rhizome dry matter was higher in the suppressed yarrow during the autumn. This resulted in a progressive reduction in the difference in rhizome dry matter between suppressed and unsuppressed populations. Several aspects of the development and regenerative potential of rhizomes were investigated. In the first experiment, plants were established from seed and rhizome fragments and harvested on several occasions. Plants from both propagules formed rhizomes on which approximately 97% of auxiliary buds remained dormant, as long as the plants were undisturbed. Buds on rhizomes attached to the parent plant formed rhizome branches when the apex was damaged, had emerged from the soil, or in situations where internodes were congested. In the second experiment, rhizome fragments of 4, 8 and 16 cm in length were planted in soil at depths of 0, 2.5, 5.0, 10.0, 20.0 and 30.0 cm. All fragments on the soil surface died without forming shoots owing to desiccation whilst 100% mortality at 20 and 30 cm was probably the result of flooding. Within the 2.5 to 10.0 cm range, an increasing percentage of fragments survived (produced an aerial shoot(s)) as burial depth was reduced and fragment length increased. Within this depth range, the percentage of buds which had become active on undecayed fragments declined with increased length and burial depth. In the third experiment, single-node rhizome pieces were excised from rhizomes retrieved from field populations over a one year period, and incubated at 25°C for 10 days in darkness. More than 90% of buds formed vertical shoots throughout the year, indicating there was no period of innate dormancy in isolated buds. The effect of time of planting on the pattern of early regenerative development was assessed in the fourth experiment, in which 10 cm rhizome fragments were planted at 5 cm depth in soil on two occasions (in November and April). The developmental pattern was the same regardless of month of planting and new rhizomes were initiated at nodes on the vertical subterranean shoots when 5 to 6 aerial leaves had developed. The planted rhizome fragments declined in dry weight and a minimum weight occurred at about the time when rhizome initiation began.

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