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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.
11

Approches biochimiques et bioinformatiques pour l'étude de la relation structure/fonction des peptides antimicrobiens d'origine végétale / Biochemical and bioinformatical approaches to study of the structure-function relationships of antimicrobial plant peptides

Hammami, Riadh 13 April 2009 (has links)
Des approches différentes mais complémentaires de bioinformatique et de biochimie ont été utilisées lors de cette étude dans le but d’identifier, d’étudier et de caractériser de nouveaux peptides antimicrobiens d’origine végétale. Dans un premier temps, et compte tenu de la grande diversité des peptides antimicrobiens mis au jour jusqu’à présent, nous nous somme fixé comme premier objectif de développer une plateforme informatique complète comprenant un logiciel, Scientific DataBase Maker (SciDBMaker) et une base de données baptisée PhytAMP. Cette plateforme permet l'extraction, l’analyse et le triage de données sur les protéines à partir de la base de données Swiss-Prot. Elle permet également de rassembler des informations taxonomiques, microbiologiques et physico-chimiques importantes sur les peptides antimicrobiens des plantes. Ainsi la constitution de cette plateforme ouvre de nouvelles perspectives informatives, en particulier celles relatives à la prédiction des relations structure / fonction en relation avec les organismes cibles et donc leur mode d’action. Dans un deuxième temps, une approche expérimentale a été utilisée afin d’évaluer le potentiel antimicrobien de quelques plantes spontanées issues des régions arides de la Tunisie. Ainsi, l’activité antimicrobienne d’Oudneya africana R. Br. (Brassicaceae), de Juniperus phoenicea L. (Cupressaceae) et de Pistacia atlantica Desf. (Anacardiaceae), trois espèces de plantes spontanées utilisées à des fins médicinales dans les zones arides de la Tunisie, de même que leurs propriétés physico-chimiques ont été évaluées. Les résultats obtenus ont montré la présence d’une activité antimicrobienne dans les trois plantes étudiées. Cette étude comparative a établi clairement le potentiel des plantes médicinales spontanées des régions arides de la Tunisie comme source d’agents antimicrobiens. Une étude poussée réalisée sur un extrait actif de l’une des trois plantes, Oudneya africana, a montré la présence de molécule peptidique de faible masse moléculaire ayant un très large spectre d’action antimicrobien. L’étude de cet extrait a été effectuée et a permis de mettre en évidence le potentiel d’exploitation aussi bien dans le secteur agroalimentaire que pharmaceutique de ces molécules bioactives naturelles. Notre travail constitue une contribution importante à l’étude des peptides antimicrobiens d’origine végétale. Des informations scientifiques très originales ont été générées tout au long de notre étude. Les connaissances fondamentales et appliquées générées ouvrent des perspectives multiples pour une exploration plus poussée de ce champ d’activité encore très peu exploité. / Different approaches but complementary in bioinformatics and biochemistry have been used during this study to identify, investigate and characterize new plant antimicrobial peptides. At first, and given the wide diversity of antimicrobial peptides uncovered so far, we have set the first goal to develop a platform that includes software, Scientific DataBase Maker (SciDBMaker) and a database PhytAMP. This platform allows the extraction, analysis and sorting of data on proteins from the Swiss-Prot database. It can also gather taxonomic, microbiological and physicochemical information on plant antimicrobial peptides. Thus the development of this platform opens up new informative prospects, particularly those relating to the prediction of structure / function in relation to the target organisms and thus their mode of action. In a second time, an experimental approach was used to evaluate the antimicrobial potential of some spontaneous plants from arid regions of Tunisia. Thus, the antimicrobial activity of Oudneya africana R. Br (Brassicaceae), Juniperus phoenicea L. (Cupressaceae) and Pistacia atlantica Desf. (Anacardiaceae), three spontaneous plant species used for medicinal purposes in the arid areas of Tunisia, as well as their physicochemical properties have been evaluated. The results showed the presence of antimicrobial activity in the three studied plants. This study has clearly established the potential of medicinal plants growing wild in arid regions of Tunisia as a source of antimicrobial agents. A study conducted on an active extract of one of three plants, Oudneya africana, showed the presence of peptide molecule of low molecular weight with a very broad spectrum antimicrobial action. The study of the extract was performed and revealed the potential of such bioactive natural molecules for exploitation in both the food and pharmaceutical industries. Our work is an important contribution to the study of plant antimicrobial peptides. Very original scientific informations have been generated throughout our study. The generated fundamental and applied knowledge open multiple perspectives for further exploration of this field of activity which still untapped.
12

Sobre veias d’águas e segredos da mata : Filosofia Ubuntu no Terreiro de Tambor de Mina

Saraiva, Luís Augusto Ferreira 26 February 2018 (has links)
Dissertação (mestrado)—Universidade de Brasília,Instituto de Ciências Humanas, Programa de Pós-Graduação em Metafísica, 2018. / Submitted by Raquel Viana (raquelviana@bce.unb.br) on 2018-06-25T20:50:38Z No. of bitstreams: 1 2018_LuísAugustoFerreiraSaraiva.pdf: 1557057 bytes, checksum: 353d92ffecb8658bea3f4f33c938e457 (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2018-06-29T16:54:44Z (GMT) No. of bitstreams: 1 2018_LuísAugustoFerreiraSaraiva.pdf: 1557057 bytes, checksum: 353d92ffecb8658bea3f4f33c938e457 (MD5) / Made available in DSpace on 2018-06-29T16:54:44Z (GMT). No. of bitstreams: 1 2018_LuísAugustoFerreiraSaraiva.pdf: 1557057 bytes, checksum: 353d92ffecb8658bea3f4f33c938e457 (MD5) Previous issue date: 2018-06-25 / O presente trabalho buscou fazer uma reflexão sobre o estudo da Filosofia Africana na potencialidade de compreender outros espaços de produção do conhecimento filosófico. Dessa forma, o estudo visa apresentar e discutir sobre a Filosofia Ubuntu, esta que é uma Filosofia da compreensão Bantu de mundo. Nesta pesquisa foi possível fazer uma leitura das noções de pessoa, e comunidade que são presentes no Tambor de Mina. O Tambor de Mina é uma religião originada da experiência negro africana no Brasil e que é bastante difundida no nordeste do país, em especial no Estado do Maranhão. A nossa intenção é fazer uma leitura do Tambor de Mina a partir da perspectiva Ubuntu e entender que as religiões afro-brasileiras e de matriz africana são produtoras de conceitos como também expressões da Filosofia. / Le présent travail a cherché à réfléchir sur l'étude de la philosophie africaine dans le potentiel de compréhension d'autres espaces de production de la connaissance philosophique. Ainsi, l'étude vise à présenter et à discuter de la Philosophie Ubuntu, qui est une Philosophie de la compréhension Bantu du monde. Dans cette recherche, il était possible de faire une lecture des notions de personne et de communauté qui sont présentes dans le Tambor de Mina. Le Tambor de Mina qui est une religion est issu de l'expérience africaine noire au Brésil et est très répandue dans le nord-est du pays, en particulier dans l'État du Maranhão. Notre intention est de faire une lecture du Tambor de Mina du point de vue d'Ubuntu et de comprendre que les religions afro-brésiliennes et africaines sont des producteurs de concepts et d'expressions de la philosophie.
13

O espaço diaspórico nas literaturas africanas de língua portuguesa

PEREIRA, Kleyton Ricardo Wanderley 12 February 2015 (has links)
Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-02-16T18:19:34Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Kleyton Pereira - TESE Letras-PPGL UFPE.pdf: 2120761 bytes, checksum: 92223cd6c83ce8d4bbed596db06e76a6 (MD5) / Made available in DSpace on 2016-02-16T18:19:34Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Kleyton Pereira - TESE Letras-PPGL UFPE.pdf: 2120761 bytes, checksum: 92223cd6c83ce8d4bbed596db06e76a6 (MD5) Previous issue date: 2015-02-12 / CAPES / O presente estudo investiga os espaços diaspóricos nas literaturas africanas de língua portuguesa. Para isso, partimos do pressuposto de que, construído a partir da intersecção entre diáspora, fronteira e deslocamentos, o espaço diaspórico está centrado nas configurações de poder e que, por isso, se transforma num espaço dinâmico de negociação (trans)cultural, uma encruzilhada de culturas. Primeiramente, procuramos construir o arcabouço teórico sobre a diáspora, distinguindo entre aquelas que são consideradas como históricas, das contemporâneas. Assim, entendemos que estas são caracterizadas pela heterogeneidade e estão vinculadas às dinâmicas do capitalismo global e aos efeitos do pós-colonialismo, numa interação complexa de relações de poder entre lugares de origem e fixação. Observamos que nas literaturas africanas de língua portuguesa, a experiência da diáspora é vivenciada de maneiras diferentes e pode provocar reações as mais diversas, tanto naqueles que retornam ao seu lugar de origem (quando retornam), quanto nos que os recebem (uma segunda pátria, talvez). Associado a essa ideia, problematizamos a questão do espaço a partir de um diálogo crítico e transdisciplinar entre seu conceito na teoria literária e as várias ciências que o consideram elemento fundamental de seus estudos, a saber, a Filosofia, a Geografia, a Sociologia, e outras. A partir desse entrelaçamento, foi possível elaborar uma síntese teórica para analisá-lo enquanto uma categoria ficcional que dialoga não só com os elementos internos da obra, foco narrativo, personagem, tempo, como também externos, o “espaço da identidade”. Por fim, analisamos algumas obras das literaturas africanas de língua portuguesa procurando identificar a construção e configuração dos espaços diaspóricos e, em consequência disso, a identidade cultural proveniente das relações entre os agentes da (pós)-colonização. A metodologia do nosso trabalho teve caráter bibliográfico e analítico, baseando-se nos pressupostos da teoria do romance e dos Estudos Culturais. Diante disso, percebemos que as obras escolhidas para compor nosso corpus de análise possibilitam compreender melhor, a partir da relação entre obra ficcional e seu contexto de produção, o processo de construção da configuração dinâmica do espaço e das diferentes identidades diaspóricas que compõem as matrizes culturais das sociedades dos países africanos de língua portuguesa. / The present study investigates diasporic spaces in the Literatures of Lusophone Africa. For this, we assume that, built from the intersection of diaspora, border and displacements, diasporic space is centered on power settings, therefore, becoming a dynamic space of (trans)cultural negotiation, a crossroad of cultures. Firstly, we engaged in the articulation of a theoretical framework on diaspora distinguishing between historical and contemporary diasporas. In this, we understand that contemporary diasporas are characterized by heterogeneity, the dynamics of global capitalism and the effects of post-colonialism, in a complex interplay of power relations between places of origin and fixation. We observed that in African Literature written in Portuguese, diaspora is experienced in different ways and cause different reactions on those who return to their place of origin and on those who receive them (a possible second homeland). Bearing this in mind, we discuss the issue of fictional space using a critical and transdisciplinary dialogue between its concept in literary theory and the various sciences which consider space as a key element for their studies -such as Philosophy, Geography, and Sociology. Based on this entanglement, it became possible to build a theoretical synthesis to analyze space as a fictional category that dialogues not only with the internal elements of a work of fiction, such as narrative focus, character, time, but also with external elements, the “space of identity”. Finally, we analyzed some works from African Literature written in Portuguese trying to identify the construction and layout of diasporic spaces and therefore the cultural identity resulting from the relationship between agents of the (post)-colonization. The methodology of our study was bibliographic and analytical, based on the theory of the novel and Cultural Studies. Finally, we realize that the works chosen as the corpus of analysis enable us to better understand from the relationship between the fictional work and its context, the construction process of the dynamic configuration of space and the different diasporic identities that make up the cultural matrix of societies from Portuguese-speaking African countries.
14

Contribuição para o conhecimento dos alcalóides indólicos de Burkea Africana Hook

Ferreira, Margarida Alice January 1971 (has links)
No description available.
15

La Inmigración Africana en Zaragoza . Espacio, discurso y memoria de los procesos migratorios en Aragón

Gallego Ranedo, Carmen 08 February 2002 (has links)
El objetivo general es conocer los procesos migratorios en Aragón y más concretamente de la inmigración de origen africano a Zaragoza.La aproximación teórica al fenómeno migratorio, desde varias disciplinas, ha puesto en evidencia la preocupación de los científicos sociales por explicarlas. Haciendo un repaso por las mismas, se ha visto que han pasado por las teorías de la modernización, al dependentismo y descansando actualmente en las articulacionista.Entendemos la emigración/inmigración como un proceso que se va configurando constantemente ya que es dinámico, por lo tanto no situacionista. Comprendemos estos actuales circuitos migratorios en un marco transnacional y dentro de unas desigualdades estructurales entre países del Norte con respecto a los del Sur.Tomando en cuenta las decisiones individuales, vemos la importancia de la pertenencia o no a una red social básica, auténtica agencia intermedia entre los individuos y los sistemas sociales. También valoramos la inclusión de la perspectiva de género en el análisis. En síntesis, para comprender los procesos migratorios internacionales actuales hay que tener en cuenta aspectos macroestructurales como microestructurales, la dimensión individual y la colectiva, la sociedad de origen y la receptora.Desde el punto de vista estructural, Aragón es tanto un lugar para emigrar como para residir, un sitio donde los desequilibrios y contradicciones del sistema capitalista expulsan, a la vez que atraen, a muchas personas. Hay un continuum migratorio, un proceso de sangría poblacional del medio rural hacia el urbano que viene a engordar la ya de por si macrocelafia zaragozana. En la situación actual se ve como hay una sustitución de los antiguos inmigrantes interiores por otros que llegan de otros países.La inmigración extranjera en Aragón es fundamentalmente compuesta por personas jóvenes, varones, que se ubican en los enclaves agrícolas en menor medida pero que sobre todo se instalan en Zaragoza capital.También nos han interesado los discursos sobre la presencia de esos "otros" dentro de la comunidad del "nosotros". Hemos analizado dos fuentes del discurso, por una parte, el de los medios de comunicación y más en concreto la prensa escrita regional, para concluir que son tanto espejo de lo que ocurre en la sociedad como motores de opinión pública.Finalmente, hemos recogido y analizado, en los tres últimos capítulos, el discurso de los propios inmigrantes de origen africano asentados en la ciudad de Zaragoza. Hemos descrito, analizado y comparado el proceso migratorio emprendidos por ellos, a través de relatos de vida, en donde se ha puesto en evidencia la importancia de la memoria migratoria y de las distintas estrategias de ocupación de un espacio físico y social. Hemos visto en antes, como momento en el cual se toma la decisión de emigrar y hemos podido descubrir el abanico causal que explicitan para dar cuenta de ese universo que presiona, a los individuos y a las familias, para emprender un viaje de impredecible retorno.El momento del tránsito, de rebasar fronteras geográficas, también lo hemos descrito e interpretado, pero también nos ha interesado averiguar la importancia vital que tiene rebasar las fronteras simbólicas.Por último, nos hemos detenido en el lugar de recepción, siendo Zaragoza el espacio en el cual hemos podido apreciar esas estrategias identitarias, esas dificultades encontradas, esas realidades a las cuales deben adaptarse y los distintos mecanismo de supervivencia en inmigración. / OF DOCTORAL THESIS "African Immigration in Saragossa. Space, Discourse and Memory in Migratory Processes in Aragon". By: Carmen GALLEGO RANEDOSupervisor: Joan Josep PUJADAS MUÑOZOverall objective: to establish what the migratory processes are in Aragon, specifically immigration of African origin into Zaragoza. Emigration/immigration is understood as a dynamic, constantly evolving process. These current migratory circuits are looked at in a transnational context, taking into account structural inequalities between southern hemisphere countries as opposed to northern.Having taken account of decisions taken by the individual, the importance of a basic social network, a real mediating agency between the individual and social systems, is acknowledged. Gender-specific perspective is also examined. In order to understand current international migratory processes one must look at issues of macro- as well as microstructures, the individual and the collective dimensions, the society of origin and the receiving society.From a structural point of view, Aragon is both a place to emigrate to and also a place in which to reside, a place where the imbalances and contradictions of the capitalist system serve to both attract and drive away many people. There is a migratory continuum, a process of population haemorrage from rural to urban areas, which further increases the already existing macrocephalalgia in Zaragoza. In the current situation we can see how previous, older patterns of internal migration are being replaced by immigration from other countries. Foreign immigration into Aragon consists in the main of young males, a minority of whom will settle in agricultural areas, but who will in the main settle in the city of Zaragoza itself. Another aspect of the research is the discourse surrounding the presence of the Other in our midst. Two main sources of discourse have been analysed: the media in general, and more specifically, regional/local press, the conclusion arrived at being that the latter are not only mechanisms contributing to the creation of public opinion, but also a mirror of our society.The last 3 chapters are given over to the analysis of the discourse of those African immigrants resident in the city of Zaragoza. Their migratory processes are described, analysed and compared, using their personal accounts of their experiences, which have revealed the importance of migratory memory and the various strategies adopted for occupying both social and physical space. The thesis looks at the past of these people, as being the location in which the decision to emigrate is taken: it has thus been possible to identify a range of causal factors which help paint a picture of the world in which people feel pressured to undertake journeys from which they may never return. The moment of transit, of crossing geographical borders, is also described and interpreted, as is the vital significance of crossing symbolic frontiers. Finally, close attention is paid to the place of reception, Zaragoza being the location in which it has been possible to reach an appreciation of the strategies adopted in order to establish identity, to deal with difficulties encountered, to deal with the realities to which people have to adapt, and to observe the various survival mechanisms of immigration.
16

Genetic variation in Cordia africana Lam. in Ethiopia

Abayneh Derero January 2007 (has links)
Zugl.: Göttingen, Univ., Diss., 2007
17

A Philosophical Analysis of Nihilism and Antiblack Racism

Johnson, Devon Ralston January 2013 (has links)
This dissertation offers a philosophical analysis of nihilism and antiblack racism. I argue that nihilism, the phenomenon espoused by Friedrich Nietzsche, is an implicit feature of antiblack racism. As a result of the implicit nihilism involved in antiblack racism, black existential life occupies a black nihilistic situation. In response to the black nihilistic situation, one can respond either weakly, as I argue is the case with Cornel West and Derrick Bell, or strongly, as I argue is the case with Frantz Fanon. I conclude that strong black nihilism is a healthy response to nihilism and antiblack racism because it is a trans-valuation of traditional forms of antiblack racist valuing, which exemplifies a commitment to the language and action of constructing non-decadent human worlds premised upon the existential freedom and responsibility of all human beings. / Philosophy
18

(Re)conceptualizing Intellectual Histories of Africana Studies: Preliminary Considerations

Myers, Joshua M. January 2011 (has links)
The overarching objective of this thesis outlines the preliminary rationale for the development of a comprehensive review of the sources that seek to understand disciplinarity, Africana Studies, and Africana intellectual histories. It is the conceptual overlay for an extended work that will eventually offer a (re)conceptualization of Africana Studies intellectual genealogies. / African American Studies
19

O pequeno contador em Os da minha rua, as formas do silêncio em Ondjaki

Oliveira , Julianny Katarine Aguiar de 24 July 2015 (has links)
Submitted by Andressa Lima (andressa@uepb.edu.br) on 2016-08-10T18:22:45Z No. of bitstreams: 1 PDF - Julianny Katarine Aguiar de Oliveira.pdf: 1047262 bytes, checksum: 03b8148e278c13b28d633f22268e70fd (MD5) / Approved for entry into archive by Luciana Medeiros (luciana@uepb.edu.br) on 2016-08-17T17:25:54Z (GMT) No. of bitstreams: 1 PDF - Julianny Katarine Aguiar de Oliveira.pdf: 1047262 bytes, checksum: 03b8148e278c13b28d633f22268e70fd (MD5) / Made available in DSpace on 2016-08-17T17:25:54Z (GMT). No. of bitstreams: 1 PDF - Julianny Katarine Aguiar de Oliveira.pdf: 1047262 bytes, checksum: 03b8148e278c13b28d633f22268e70fd (MD5) Previous issue date: 2015-07-24 / Este trabajo viene de una investigación poética en huellas de la memoria dejados por el escritor y poeta en su Ondjaki El libro de mi calle. Angola, nacido en 1977, dos años después de la independencia de su país, tuvo como su fondo de la infancia de la guerra civil de Angola, en la que muchos de los escritores que le precedieron se detuvo. El propósito de este escrito es entonces ver cómo el autor rompe este ciclo escrito sobre la guerra teniendo voz subalterna del bebé para traer al mundo otra Angola. Para ello, los detuvimos en el análisis de esa obra de cuentos, ya que en este encontramos una reunión de cuentos acerca de las emociones que rodean a esta "calle" que es en sí, Angola. Guiar nuestro ojo en la estética del silencio utilizados por el autor para escribir estas historias tienen como los estudios teóricos de Eni Puccinelli Orlandi en su libro Los caminos del silencio (2011), y GayatriSpivak en Can hablar el subalterno? (2010), que se encuentran tanto en los muelles para este análisis, como dos formas distintas de silencio de trabajo pueden verse: una en el discurso silencio del campo, y que revela el silencio como la condición humana. Conocemos la importancia de la voz para el estudio de las literaturas africanas en portugués, pero suponiendo que el silencio también dice que, desde el Ondjaki escritura, dialogaremos con voz contemporánea de la tradición / O presente trabalho nasce de uma investigação poética sobre os rastros de memória deixados pelo escritor e poeta Ondjaki em seu livro Os da minha rua. Angolano, nascido em 1977, dois anos após independência de seu país, teve como pano de fundo de sua infância a guerra civil angolana, sobre a qual, muitos dos escritores que o antecederam se detiveram. O objetivo dessa escrita é então ver como o autor rompe com esse ciclo de escritas sobre a guerra tomando a voz subalterna do infante para trazer ao mundo outra Angola. Para isso, nos detivemos a análise da referida obra de contos curtos, pois nesta encontramos uma reunião de contos sobre os afetos que envolvem essa ‗rua‘ que é em si, Angola. Norteando nosso olhar sobre a estética do silêncio utilizada pelo autor para escrever essas histórias teremos como aporte teórico os estudos da Eni Puccinelli Orlandi em seu livro As formas do silêncio (2011), e GayatriSpivak, em Pode o subalterno falar? (2010), pois encontramos em ambos as molas para essa análise, uma vez que duas formas distintas de trabalhar o silêncio são apresentadas: aquela no campo do discurso do silêncio, e essa revelando o silêncio enquanto condição humana. Sabemos a importância da voz para os estudos das literaturas africanas de língua portuguesa, mas é partindo do princípio de que o silêncio também fala que, a partir da escrita de Ondjaki, dialogaremos com a voz contemporânea da tradição.
20

Seasonal variation in essential oil composition, oil toxicity and the biological activity of solvent extracts of three South African Salvia species

Kamatou, GPP, Van Zyl, RL, Van Vuuren, SF, Figueiredo, AC, Barroso, JG, Pedro, LG, Viljoen, AM 26 November 2007 (has links)
Aromatic plants contain both volatile and non-volatile fractions and the chemical composition of these two fractions may be influenced by seasonal changes. The essential oil and solvent extracts of S. africana-caerulea, S. africana-lutea and S. lanceolata, collected at the same locality throughout the 2005 growing season, were compared in terms of essential oil composition, yields and biological activities. Mostly quantitative, rather than qualitative variationwas observed in the oil composition of each species.Major fluctuations in the composition of S. africana-caerulea oil included limonene (2–33%) and viridiflorol (2–24%). Levels of α-pinene (1–12%), myrcene (2–12%) and α-eusdesmol (trace-13%) fluctuated seasonally in the S. africana-lutea oil. In S. lanceolata, considerable changeswere noted for β-caryophyllene (1–19%), β-caryophyllene oxide (1–21%) and ledol (3–12%). The extract prepared from S. lanceolata harvested inwinterwas more active against Gram-positive bacteria. The S. africana-caerulea extract exhibited the most favourable antiplasmodial activity when harvested in winter (IC50 value: 12 μgml−1), which contrasts with the lowest anti-plasmodial activity of S. lanceolata obtained at the same period (IC50 value: 43 μgml−1). The anti-oxidant activity of the solvent extracts also displayed variation over seasons with thewinter collection of S. africana-lutea yielding the most favourable anti-oxidant activity (IC50 value: 10 μg ml−1). All the solvent extracts prepared from the winter collection exhibited the lowest toxicity (20bIC50 valuesb60 μg ml−1), while the three essential oils obtained from autumn collection were more toxic (0.03bIC50 valuesb0.4 μg ml−1).

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