• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 6
  • 3
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 13
  • 13
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 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.
11

Caracteriza??o molecular e avalia??o de resist?ncia a chumbo e c?dmio em bact?rias isoladas de rizosferas de plantas coletadas em Santo Amaro (BA)

Souza, Adriana Fidelis Couto 13 March 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2015-11-12T01:11:08Z No. of bitstreams: 1 Disserta??o Adriana Fidelis - Vers?o Definitiva.pdf: 9437752 bytes, checksum: f708082e56eba193c45496d67cab5993 (MD5) / Made available in DSpace on 2015-11-12T01:11:08Z (GMT). No. of bitstreams: 1 Disserta??o Adriana Fidelis - Vers?o Definitiva.pdf: 9437752 bytes, checksum: f708082e56eba193c45496d67cab5993 (MD5) Previous issue date: 2013-03-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In the 1960? the mining company Plumbum Mineradora was installed in the Satate of Bahia, Brazil. This company, which produced lead ingots for 33 years, left over 400,000 tons of slag, which contained, among other pollutants, cadmium and lead. These metals are currently found in the soil surrounding the old factory, in concentrations considered highly toxic. A study was started to investigate possible bioremediation in the area with the isolation of bacteria from the rhizosphere of local plants, followed by the test in their performance in metals contaminant tolerance. Finally, identification of the bacteria was made based on molecular marker 16S rRNA. The isolation protocol was carry out using Nutrient Agar and after obtaining a pure culture. The isolates were then subjected to tests of Minimum Inhibitory Concentration (CIM). Each isolate served as a source for extraction of DNA for molecular analysis with 16S rRNA region. Among the rhizospheres collected, those from which the greatest number of species were isolated from plants with a perennial habit, among them the castor bean (Ricinus communis L.) and emba?ba (Cecropia pachystachya Tr?cul) which together comprised approximately 38% of all species of bacteria obtained. Interestingly, from the castor bean (an exotic plant in Brazil), 2/3 of the bacteria were Gram negative, while from the emba?ba (a native plant of Brazil), ? of the bacteria isolated were of Gram positive. Regardless of the classification of Gram, the bacteria studied showed higher tolerance to lead; 70% of Gram negative bacteria showed conspicuous morphological changes, whereas of those that were Gram positive, only 13% demonstrated. In addition, these bacteria have been identified by molecular analysis using the 16S rRNA marker. The used methodology based on analysis of parsimony and distance trees. As a result, the region 16S was able to identify only 22% of species while the remain species could only be identified to genus or to infra-generic groups. Therefore, the data suggest that the Gram negative and Gram positive bacteria have distinct mechanisms of adaptation in environments polluted by lead and cadmium and that the 16S region is not an efficient universal barcode marker, which should be used only as the first step on the identification of bacteria. Although this study does not provide a final parameter for ecological factors under consideration here, it provides an insight into the influence of the plant habitat on bacterial communites, and the role of Gram in the mechanisms of tolerance. It is hope to explore these aspects in the further studies. / Na d?cada de 60, a empresa de minera??o Plumbum Mineradora foi instalada no Estado da Bahia, Brasil. Esta empresa, a qual produziu lingotes de chumbo por 33 anos, deixou mais de 400.000 toneladas de esc?ria, a qual continha, dentre outros poluentes, c?dmio e chumbo. Estes metais s?o, atualmente, encontrados no solo do entorno das antigas instala??es da f?brica, em concentra??es consideradas altamente t?xicas. Este estudo come?ou a investigar a biorremedia??o da ?rea com o isolamento de bact?rias das rizosferas de plantas locais, seguido por testar a toler?ncia das bact?rias a esses metais. Finalmente, a identifica??o de bact?rias foi feita baseada no marcador molecular 16S rRNA. O protocolo de isolamento foi realizado em meio de Agar Nutriente e ap?s a obten??o de cultura pura, os isolados foram submetidos a testes de Concentra??o Inibit?ria M?nima (CIM). Cada isolado serviu de fonte para extra??es de DNA para an?lise molecular com a regi?o 16S rRNA. Dentre as rizosferas coletadas, as que mais se destacaram em rela??o a quantidade de esp?cies isoladas foram as plantas de h?bito perene, dentre elas, a mamona (Ricinus comunis L.) e a emba?ba (Cecropia pachystachya Tr?cul), que abrigaram juntas aproximadamente 38% de todas as esp?cies de bact?rias obtidas. Interessante notar que da mamona (uma planta ex?tica no Brasil), 2/3 das bact?rias foram Gram negativas, enquanto que da emba?ba (uma planta nativa do Brasil), 3/4 das bact?rias isoladas foram Gram positivas. Independentemente da classifica??o do Gram, as bact?rias apresentaram maior resist?ncia ao chumbo; 70% das Gram negativas apresentaram mudan?as morfol?gicas acentuadas, enquanto que estas, nas Gram positivas, manifestaram-se em apenas 13%. Al?m disso, estas bact?rias foram identificadas por meio de an?lise molecular, com o uso do marcador 16S rRNA. A metodologia usada foi baseada em an?lise de ?rvores de parcim?nia e dist?ncia. Como resultado, a regi?o 16S foi capaz de identificar 22% das esp?cies, enquanto que para o restante mostrou-se eficiente para classifica??o at? g?nero ou para agrupamentos infragen?ricos. Portanto, os dados sugerem que as bact?rias Gram negativas e Gram positivas possuem mecanismos de adapta??es distintos em ambientes polu?dos por chumbo e c?dmio e que a regi?o 16S n?o ? eficiente como marcador universal tipo ?c?digo de barras?, o qual deve ser utilizado apenas como a primeira ferramenta de identifica??o de bact?rias isoladas. Apesar deste estudo n?o servir como par?metro definitivo para considera??es ecol?gicas, ele fornece conhecimento sobre a influ?ncia do h?bito da planta sobre a comunidade bacteriana e o papel da estrutura morfol?gica das bact?rias (Gram) nos mecanismos de toler?ncia. Espera-se que estes dados possam ser explorados em estudos posteriores.
12

Определение микропримесей тяжелых металлов в лекарственном растительном сырье и препаратах на его основе методом вольтамперометрии : магистерская диссертация / Determination of trace metals of heavy metals in medicinal plant materials and preparations based on it by the method of voltammetry

Ахмерова, А. Р., Akhmerova, A. R. January 2019 (has links)
Master's thesis: "Determination of trace metals of heavy metals in medicinal plant materials and preparations based on it by the method of voltammetry." Pages 72, figures 33, tables 10, bibliographic names 19. The objects of the study were the olive leaflet CO (BCR No. 62), medicinal plant raw materials of the roots of cinchata, flax seeds, rosehips, blueberry and horsetail shoots, tincture of the Bashkir balsam “Agidel”, oil extract “Vitaon”, dry extract “Plantaglyutsid” and collection “ Pancreatitis. Objective: To develop a method for sample preparation and determination of trace impurities of lead and cadmium in medicinal plant raw materials and preparations based on it using stripping voltammetry. Analysis of the literature data showed that the best method for the determination of heavy metals in medicinal plant materials and preparations based on it is the method of inversion voltammetry, which allows to detect trace contaminants in the studied solutions. The samples were prepared by the method of microwave decomposition on the installation "MARS" in a closed system and the method of acid decomposition on the installation of the company "Hach Company" in the open system. The optimal conditions for sample preparation at the MARS facility were selected for the analyzed objects: sample weight, oxidizer composition, number of decomposition stages, power, time and temperature of sample processing. Decomposition in an open system was carried out according to a standard procedure. Sample preparation at the installation of the Hach Company allows for the analysis of IR by the IV method to obtain baselines at the level of pure solutions and clear, well-measured signals of metals, and to find microprisms of heavy metals in larger quantities than when preparing samples by microwave decomposition under optimally selected conditions. / Магистерская диссертация: «Определение микропримесей тяжелых металлов в лекарственном растительном сырье и препаратах на его основе методом вольтамперометрии». Страниц 72, рисунков 33, таблиц 10 , библиографических наименований 19. Объектами исследования служили СО листьев оливы (BCR № 62), лекарственное растительное сырьё корневищ лапчатки, семян льна, плодов шиповника, побегов черники и хвоща, настойка башкирского бальзама «Агидель», масляный экстракт «Витаон», сухой экстракт «Плантаглюцид» и сбор «Панкреатит». Цель работы: Разработка методики пробоподготовки и определения микропримесей свинца и кадмия в лекарственном растительном сырье и препаратах на его основе методом инверсионной вольтамперометрии. Анализ литературных данных показал, что оптимальным методом определения тяжёлых металлов в лекарственном растительном сырье и препаратах на его основе является метод инверсионной вольтамперометрии, позволяющий обнаруживать микропримеси в исследуемых растворах. Пробы были подготовлены методом микроволнового разложения на установке «MARS» в закрытой системе и методом кислотного разложения на установке фирмы «Hach Company» в открытой системе. Для анализируемых объектов были подобраны оптимальные условия пробоподготовки на установке «MARS»: масса навески, состав окислителя, количество стадий разложения, мощность, время и температура обработки пробы. Разложение в открытой системе было проведено по стандартной методике. Пробоподготовка на установке фирмы «Hach Company» позволяет при анализе ИР методом ИВ получать базовые линии на уровне чистых растворов и чёткие, хорошо измеряемые сигналы металлов, и находить микропримиси тяжёлых металлов в большем количестве, чем при подготовке проб методом микроволнового разложения при оптимально подобранных условиях.
13

Study on the growth and tolerance ability of Polygonum hydropiper L. and Hymenachne acutigluma (Steud.) Gilliland on Pb and Cd polluted soil

Chu, Thi Thu Ha 08 December 2015 (has links)
Two plant species including Polygonum hydropiper L. and Hymenachne acutigluma (Steud.) Gilliland were investigated in their resistance to lead (Pb) and cadmium (Cd) pollution in the soil. Lead-contaminated soil samples were collected from the lead recycling village Dong Mai, Chi Dao commune, Van Lam district, Hung Yen province, Vietnam that had Pb level up to 192,185 mg.kg-1, dry weight (DW). Cadmium-contaminated soil samples were due to supplement of CdCl2.21/2H2O to alluvial soil. Results showed that both species were highly resistant to Pb, however P.hydropiper was better. Similarly, the Cd resistance was higher for P.hydropiper than for H.acutigluma. No morpho-abnormalities of P.hydropiper regarding the impact of lead were recorded, whereas for H.acutigluma, the young leaves had white colour after two months of planting in soil containing lead levels of 192,185 mg.kg-1. The response of both species with Cd in soils included yellowing leaves, withering branches and even dying after 5-15 days exposed to Cd. Lead contents accumulated in above-ground parts of both plants were up to 4,650 and 3,161 mg.kg-1, DW, corresponding to P.hydropiper and H.acutigluma. From the research results on lead resistance and accumulation of two plant species studied, it is suggested that the two species are lead hyperaccumulators can be used for phytoremediation technology to clean contaminated soil. / Hai loài thực vật gồm nghể răm Polygonum hydropiper L. và bấc nhọn Hymenachne acutigluma (Steud.) Gilliland được nghiên cứu về khả năng chống chịu ô nhiễm chì (Pb) và cadmi (Cd) trong đất. Mẫu đất ô nhiễm chì được thu từ làng nghề tái chế chì Đông Mai, xã Chỉ Đạo, huyện Văn Lâm, tỉnh Hưng Yên, Việt Nam có hàm lượng chì lên đến 192.185 mg.kg-1, tính theo trọng lượng khô (DW). Mẫu đất ô nhiễm Cd là do được bổ sung CdCl2.21/2H2O vào đất phù sa. Kết quả cho thấy cả hai loài đều có sức chống chịu chì rất cao, tuy nhiên nghể răm có khả năng tốt hơn. Tương tự như vậy, sức chống chịu Cd của nghể răm cũng cao hơn của bấc nhọn. Không có dấu hiệu bất thường nào của nghể răm đối với tác động của chì được ghi nhận, trong khi ở bấc nhọn thì lá non có màu trắng sau hai tháng trồng trên đất có hàm lượng chì 192.185 mg.kg-1. Phản ứng của cả hai loài thực vật với Cd trong đất gồm có hiện tượng vàng lá, héo ngọn và thậm chí chết sau 5-15 ngày phơi nhiễm với Cd. Hàm lượng chì được tích lũy cao trong phần trên mặt đất của cả hai loài thực vật lên tới 4.650 và 3.161 mg.kg-1, DW, tương ứng cho loài P.hydropiper và H.acutigluma. Từ kết quả nghiên cứu về khả năng chống chịu và tích lũy chì của hai loài thực vật nghiên cứu, có thể đề xuất đây là hai loài siêu tích lũy chì có thể sử dụng trong công nghệ làm sạch đất ô nhiễm.

Page generated in 0.0273 seconds