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Screening and phytochemical characterization of a South African herbal concoction for anti-HIV-1 activityHlatshwayo, Vincent Nkosinathi January 2017 (has links)
A dissertation submitted to the Faculty of Science under the School of
Molecular and Cell Biology, University of the Witwatersrand, Johannesburg,
in fulfilment of the requirements for the degree of Master in Science.
Johannesburg, June 2017. / In South Africa, the anti-HIV-1 activity of various indigenous plants has not been
studied extensively. Most of the phytochemical screening work has focused on
anti-cancer activity with less attention given to infectious diseases. A large
proportion of South Africans (70-80%) still rely on traditional medicines for
treatment of various ailments. And, therefore, there is a need to evaluate and
validate the effectiveness of the traditional medicines. The aim of this study was
to identify, screen, phytochemically characterize and isolate bioactive compounds
from a South African herbal extract that exhibit the best anti-HIV-1 activity.
Three extracts were prepared: an ethanol extract, a dereplicated ethanol extract
and an aqueous extract from a herbal concoction comprised of a mixture of six
plants. These herbal concoctions were investigated for anti-HIV-1 subtype C
activity.
Phytochemical profiling of the ethanol- and dereplicated ethanol- extracts from
the herbal concoctions showed the presence of intermediate polar compounds
(flavonoids, alkaloids, sugars and terpenes) for both extracts, while the aqueous
extract contained predominantly highly polar compounds.
Anti-HIV-1 screening of the three extracts showed that the ethanol and
dereplicated ethanol herbal- extracts had the best anti-reverse transcriptase
activity. The ethanol extract had mean IC50 values of 56.53, 53.96 and 55.39
μg/ml against MJ4, Du179 and CM9 HIV-1 subtypes C isolates, respectively. The
dereplicated ethanol extract had mean IC50 values of 51.87, 47.56 and 52.81
μg/ml against MJ4, Du179 and CM9 HIV-1 isolates, respectively. The aqueous
extract was inactive against HIV-1 activity.
Moreover, both the ethanol- and dereplicated ethanol- extracts showed activity
against HIV neutralization. The ethanol- and dereplicated ethanol- extracts had
mean IC50 values of 36.33 and 32.06 μg/ml, respectively. Furthermore, they also
potently neutralized Vesicular stomatitis virus (VSV) yielding mean IC50 values
of 24.91 and 20.82 μg/ml for ethanol- and dereplicated ethanol- extracts,
respectively. All extracts were inactive against Murine leukemia virus (MLV).
The isolation and phytochemical characterization of the bioactive compound(s)
was done by utilizing various chromatographic and spectroscopic methods. Four
homoisoflavanoids were isolated and tested for anti-HIV-1 subtype C activity.
Three compounds (1, 3a and 3b) were inactive while compound 2 was found to be
bioactive against HIV-1 reverse transcriptase (RT) and yielded mean IC50 values
of 7.23 ± 1.88, 12.83 ± 0.41 & 12.81 ± 0.10 μg/ml for MJ4, CM9 and Du179
HIV-1 subtype C isolates, respectively. Compound 2 had a mean CC50 value of
23.08 ± 0.1981 μg/ml against HEK293T cells.
Overall, the data suggested that ethanol- and dereplicated ethanol- herbal extracts
possess direct and indirect anti-HIV-1 activity. They possess a cocktail of
phytochemicals that can inhibit HIV-1 RT, HIV-1 entry. Furthermore, these
extracts possess phytochemicals that can lower the activation of inflammatory
responses during an infection and, hence, reduction in the number new cells
infected during the course of HIV-1 infection. Moreover, they possess
phytochemicals that have antioxidant activity which, in relation to HIV infection,
results in a boosted immune system response in order to ward off the virus. / MT 2017
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The design of a risk assessment model to determine the impact of the herbal medicine trade on the Witwatersrand on resources of indigenous plant speciesWilliams, Vivienne Linda 08 August 2008 (has links)
Exploitation of botanical resources has resulted in significant decreases in the sizes of some plant populations, especially for species that have a high commercial value and are important to the lives and livelihoods of rural communities. Medicinal plant resources are used and traded commercially in both rural areas and urban centres, and over-exploitation has become a deterministic factor in the extinction risks to certain species. The main aim of the study was to design a risk assessment model to determine the impact of the medicinal plant trade on the Witwatersrand (centred around Johannesburg) on indigenous plant resources. The goal was to incorporate trade variables correlated with harvesting risks together with biological characteristics of the harvested species to predict which species are most threatened by the trade and are thus high on the list for conservation priority.
The study required semi-quantitative surveys of the medicinal plants sold by traders in the Witwatersrand to be conducted. In 1994 and 2001, the plants sold in 50 muti shops and by 100 vendors in the Faraday Street market respectively were inventoried. Quantitative trade data were also captured, including volume, pricing structures and plant size (e.g. bark thickness and bulb diameter). A scientific sampling strategy was adhered to throughout the study to add statistical validity to the results. In a novel approach to analysing ethnobotanical data, the frequency of plant occurrences in the markets was analysed using measures (analysed by EstimateS) of species diversity traditionally used in ecology. The measures allowed for sampling strategies and sizes to be compared between data sets and for the number of species likely to be sold in the region to be estimated. Furthermore, data sets could be compared in terms of species richness, diversity, evenness and complimentarity.
Another novel approach taken in the thesis was to estimate the number of individual plants harvested annually by gatherers, specifically the number of trees that are debarked and the number of whole bulbs that are removed. In order to estimate the number of trees debarked, a study was conducted to determine the relationship between bark thickness and stem diameter for six species. The results made it possible to estimate the condition of the resource in the wild from market records (i.e. bark thicknesses) and to see how the availability of larger trees has declined for species such as Warburgia salutaris between 1994 and 2001. Results for bulbs showed that there has been a significant decrease in the diameter of Eucomis autumnalis bulbs present in the markets in the same period, suggesting significant levels of resource depletion.
The thesis explored the use of a multivariate methodology for assessing the extinction risks of species and assigning species harvested for the medicinal plant trade to various hierarchies of risk and conservation priority. Hierarchical and non-hierarchical cluster analysis (Ward’s and K-means respectively) methods were found to be effective in assigning species to clusters of similar risk and conservation priority. From a combined list of 392 ethnospecies recorded in the muti shops and Faraday market, a short-list of 119 higher risk species was identified using four to five trade variables. This list was further reduced to 87 species to ascertain conservation priorities based on the additional inclusion of seven biological variables in the assessment. From this list, approximately 31 species were identified as having higher conservation priority and would be candidates for further research, management and protection within the ambit of conservation and sustainable utilisation programmes. These species would further benefit from Orange Listing or having their IUCN Red List status re-evaluated.
The methods developed in this study are recommended for other ethnobotanical studies. Furthermore, the risk assessment method could be applied to the assessment of species similarly traded in other medicinal plant markets or applied to the assessment of species under threat from other stressors at a regional, provincial and/or national level using the appropriate variables.
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Guardiãs das folhas: mobilização identitária de raizeiras do cerrado e a autorregulação do ofício / Guardians of the leaves: the identity mobilization of the raizeiras of the Brazilian cerrado and ploy´s self-regulationD\'Almeida, Sabrina Soares 10 September 2018 (has links)
O presente trabalho propõe uma reflexão acerca da recente mobilização de raizeiras do cerrado em torno do que denominam como a identidade da raizeira. Organizadas em torno da Articulação Pacari, estas raizeiras vêm se mobilizando, desde 1998, com o objetivo de reivindicar o direito de praticar a medicina tradicional. Contudo, sua atuação extrapolou o campo da saúde propriamente dito ao adentrar em arenas de debates e demandas nas quais são discutidas questões como território, identidade, cultura, etnia, entre outros temas caros aos povos e comunidades tradicionais brasileiros. Isso se justifica porque estas raizeiras, desde 2006, são reconhecidas enquanto um dos gruposmembro da Comissão Nacional de Desenvolvimento Sustentável dos Povos e Comunidades Tradicionais (CNPCT). Ao articular duas pautas de importância global a saúde e o meio ambiente estas raizeiras produzem para si um novo espaço de atuação, ressignificam práticas e saberes e vão, aos poucos, tecendo sua narrativa identitária em torno da qual passam a organizar suas reivindicações por direitos. / The actual assignment implies a thinking over the recent mobilization of the raizeiras of the Brazilian cerrado upon the topic ´raizeira´s identity´. These raizeiras are arranged within the surroundings of the Pacari Joint; they started to gather in 1998, reclaiming their rights to practice traditional medicine. Nonetheless, their actions extrapolated issues in the human health field scarcely; their actions in arena of debates and demands do now include issues such as territory, identity, culture, ethnicity, amongst other matters dear to traditional Brazilian people and communities. That is justifiable because in 2006 these raizeiras were embodied as a member group of the National Commission of Sustainable Development of Traditional People and Communities (Comissão Nacional de Desenvolvimento Sustentável dos Povos e Comunidades Tradicionais, CNPCT). When articulating two schedules of global significance health and environment these raizeiras generate for themselves a new acting room; they give new meaning to practices and knowledge, and they go little by little weaving their identity narrative around which they begin to organize their claims for rights.
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Quantitative and qualitative optimization of antimicrobial bioactive constituents of Helichrysum cymosum using hydroponics technologyMatanzima, Yonela January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Horticulture
in the Faculty of Applied Sciences
at the Cape Peninsula University of Technology / The high demand for medicinal plants has favoured over-exploitation of wild plants. The
search for alternative and sustainable methods of medicinal plant cultivation is imperative and
desirable. Biotechnological approaches particularly hydroponic technology has the potential
for large scale plant cultivation and production of secondary metabolites. The current study
aims at optimizing the production of antimicrobial secondary metabolites by an indigenous
South African medicinal plant species (Helichrysum cymosum) through hydroponics N and K
fertilization. In Chapter 1, the conceptual framework and justifications of the study are
presented. In Chapter 2 the research objective was to discern the optimal potassium (K)
supplement level for H. cymosum by evaluating the effects of different hydroponic K levels
on growth, K-leaf content, and anti-Fusarium oxysporum f.sp.glycines (Ascomycota:
Hypocreales) and total activities. Six weeks old seedlings of H. cymosum were treated with
varied concentrations of K in the form of potassium chloride, potassium nitrate and
monopotassium phosphate (58.75, 117.5, 235 and 470 ppm). These concentrations were based
on a modification of Hoagland’s hydroponic nutrient formula. Plants were maintained under
greenhouse conditions and growth parameters (plant height and number of leaves) were
recorded weekly. At 8 weeks post treatment, plants were harvested and fresh weights were
recorded and tissue nutrient content analysed. Sub-samples of the aerial parts of plants grown
in the different treatments were air dried, extracted with acetone and tested against F.
oxysporum. Plants exposed to 235 ppm K showed a marked increase in leaf number, plant
height and fresh weight. Overall there was no significant difference (P > 0.05) among the
treatments with respect to tissue nutrient content; K ranged from 3.56 ± 0.198 to 4.67 ± 0.29
%. The acetone extraction yield increased with increasing K fertilization: 58.75 ppm (16.67 ±
2.35 mg), 117.5 ppm (22.5 ± 4.79 mg), 235 ppm (210 ± 38.5 mg) but dropped to 40 ± 4.08
mg at 470 ppm K. Results from the anti-F. oxysporum bioassay showed that 58.75 and 235 ppm K treatments produced the most bioactive acetone extracts; MIC values of 0.49 and
0.645 mg/l, respectively. Acetone extracts obtained from plants exposed to 235 ppm K
yielded the highest total activity, comparatively (P < 0.05). In conclusion, the optimum
nutrient K level for growing H. cymosum hydroponically was 235 ppm.
Chapter 3 focused on another important macro nutrient N and the objective was to determine
the optimum nutrient requirements for growing the medicinal plant, Helichrysum cymosum
(L.) (Asteraceae), hydroponically. Experiments were conducted to assess the effects of varied
nitrogen (N) concentrations supplied as nitrate and ammonium on growth, tissue nutrient
content, antimicrobial and total activities of acetone extracts of aerial parts. Treatments were
based on a modified Hoagland’s nutrient formula. Six week old rooted cuttings were treated
with 52.5 ppm, 105 ppm, 210 ppm and 420 ppm of N. Leaf number and stem height (cm)
were recorded at weekly intervals and leaf analysis conducted. The effects of N treatments on
plant growth parameters varied significantly among treatments; 52.5 ppm of N yielded the
tallest plants (height) [19.4 ± 0.7 cm], while 105 ppm N yielded the maximum leaf number
(68.1 ± 6.2) as well as maximum fresh weight of aerial parts was obtained with 105 ppm
(15.12 ± 1.68 g). Nitrogen content of plant tissue ranged between 0.53 ± 0.03 and 4.74 ±
0.29% (d, f, 3, 12; f=14; P ≤ 0.002) depending on treatments. Powdered aerial parts (5 g) of
H. cymosum obtained from the different N treatments were extracted with 100 ml of acetone.
N treatment significantly affected the yield of crude extracts, which ranged from 87.5 ± 15.5
(52.5 ppm) to 230 ± 23.5 mg (105 ppm). Acetone extracts of plants that were exposed to
varied N treatments were screened for anti-Fusarium oxysporum activity using minimum
inhibitory concentration (MIC) method. The MIC value (0.073 ± 0.014 mg/ml) obtained with
acetone extracts of plants exposed to 52.5 ppm N was significantly lower compared to the
MICs of the other N treatments (105 [0.47 ± 0 and 0.705 ± 0.135 mg/ml], 210 [0.234 and 0.47
mg/ml] and 420 ppm [0.29 ± 0.101 mg/ml]) at 24 and 48 hours respectively. However, the
total activities of extracts obtained among the four N treatments, which ranged from 0.062 ±
0.02 to 0.26 ± 0.06 ml/g was not statistically different at 24 or 48 hours (P > 0.05). LC-MS
analysis of acetone extracts of H. cymosum plants obtained from the four treatments hinted
that known anti-microbial agents such as apigenin, quercetin, kaempferol, helihumulone and
quinic acids were present in the extracts and the quantity of helihumulone increased with
increased nutrient N level.
These results suggest that H. cymosum may be cultivated hydroponically and that the
antimicrobial activity and/or the phytochemical profile of the crude acetone extracts is
affected by nutrient nitrogen levels. Hydroponic cultivation of plants may be able to alleviate
to an extent the pressure on wild medicinal plants.
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20+1 cartas : travessias em direção a uma psicanálise em MoçambiqueYusuf, Yanisa January 2018 (has links)
Esta escrita está metaforizada com a ideia de uma travessia, a minha travessia. Uma Moçambicana, com o desejo de conhecer uma Psicanálise voltada a questões da Saúde Mental e que participe ativamente da construção de Políticas Públicas se encontrou e se reconheceu como pesquisadora, entre idas e vindas de dois países com histórias tão parecidas e, ao mesmo tempo, tão diferentes, mas que têm na sua constituição marcas profundas da colonização à qual estiveram submetidos durante anos. Em Moçambique, a Independência conta com apenas 42 anos, sendo assim um país novo e em construção da sua identidade. Para compor esta pesquisa, vários reencontros com o meu país foram necessários.Pelo desejo de poder construir uma Psicanálise capaz de dialogar com as especificidades de um povo único e singular como o moçambicano, me parece necessário pensar sobre a Saúde Mental moçambicana e também conhecer melhor a Medicina Tradicional, que é uma prática de cuidado com o outro que existe há milénios no continente africano. Através de cartas dirigidas a pessoas que vêm compondo este caminho comigo, e de entrevistas aos vários profissionais de saúde que se dedicam à escuta do sofrimento dentro da minha terra natal, me proponho a pensar numa interlocução entre a Medicina Tradicional e os saberes provenientes de uma lógica ocidental, a fim de que se possa construir práticas de cuidado capazes de dialogar com a cultura moçambicana. / This writing is metaphorized using the idea of a journey, my journey. A Mozambican, with the desire of knowing a psychoanalysis focused on Mental Health issues and actively participating in the construction of Public Policies, found herself and became a researcher, between comings and goings of two countries with stories that are so similar and, at the same time, so different, but which have in their constitution profound marks of colonization they have been subjected to for years. In Mozambique, independence is only 42 years old, so it is still a new country and is still building its identity. In order to compose this research, several reunions with my country were necessary, and for the desire of building a Psychoanalysis able to engage with the particularities of a unique and particular people like the Mozambican, I believe it is necessary to think about the Mozambican Mental Health and also to get to know Traditional Medicine, which is a practice of caring for the other that has existed for millennia on the African continent. Through letters addressed to people who have been composing this path with me, and interviews with the various health professionals who dedicate themselves to listen to suffering within my native land, it is proposed to think of an interlocution between traditional medicine and the knowledge from a Western logic, so that care practices capable of dialoguing with Mozambican culture can be built.
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The Nigerian healthcare system: A study of access to affordable essential medicines and healthcareObuaku-Igwe, Chinwe Christopher January 2015 (has links)
Philosophiae Doctor - PhD / The concepts of availability, affordability, accessibility and acceptability otherwise known as the 4As of ATM are key factors that influence access to essential medicines in any given health system. However, the exact scale and extent to which these 4As affect various populations in Nigeria remains unknown. This study investigates the Nigerian healthcare system with special focus on access to quality and affordable essential medicines in three Nigerian States; Abuja, Kaduna and Nassarawa, by drawing upon primary data, using qualitative and quantitative research methods.
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Pill, Plant or Pray? Siwan Berbers’ experiences of illness, cure and reliefEriksson, Stephanie, Johansson, Maria January 2008 (has links)
This study is a part of the Minor Field Study Programme funded by the Swedish International Development Cooperation Agency (Sida). The study was carried out during the spring of 2008 in the oasis of Siwa. Siwa is situated in the western desert of Egypt. The authors had been informed about the health care resources available and that people only to some extent used those. The study has a qualitative approach and the essay is based on the experiences of seven respondents. The aim of the study is to describe Siwan Berbers’ experiences of illness, cure and relief. Semi structural interviews were conducted and the data was analysed through a qualitative content analysis. The result was compiled into three themes which further were divided into sub themes. The themes were: “the idea of illness”, “explanation models to illness” and “relief and cure”. The result shows that the views on causes to illness affect the actual choice of cure and relief chosen. Furthermore, financial aspects are considered and it is also essential to feel confidence to the caregiver in order to achieve cure and relief. The result is discussed in relation to the background and relevant literature concerning cultural and developing issues. This Minor Field Study is important since it enlightens some of the factors a person takes into consideration when he or she selects alternatives for cure and relief during the illness experience. / <p>Program: Sjuksköterskeutbildning</p><p>Uppsatsnivå: C</p>
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In vitro determination of efficacy of indigenous plant extracts used for internal parasites control by small-holder livestock farmers in Chief Albert Luthuli Municipality, Mpumalanga Province, South AfricaShiba, Mlungisi Richard January 2018 (has links)
Thesis (M. Agricultural Management (Animal Production)) -- University of Limpopo, 2018 / Ethno veterinary medicine practices are popular among the resource constrained small-holder farmers. Nonetheless, the effectiveness of traditional remedies particularly the indigenous plants has not been extensively documented. Hence, this study was conducted to determine efficacy of indigenous plant extracts used by small-holder farmers in Chief Albert Luthuli Local Municipality, Mpumalanga Province, South Africa for internal parasites control. Information on indigenous plants used for the control of internal parasites of livestock by local farmers in the study area was gathered through a questionnaire survey. A total of 188 livestock farmers (both males and females) of mixed ages were interviewed. Thirteen different plants were frequently mentioned by the respondents as remedies for livestock internal parasites. Of these, seven plants could be identified up to their families and species. Plant species collected were Dicerocaryum sp (50%), Pappeacapensis (61%), Aloe ferox (90%), Helichrysum sp (56%), Senecio congestus (83%), Senecio barbertonicus (67%) and Gardenia sp (73%). These plants were extracted using distilled water and analysed to determine their efficacy through in vitro assays; Egg hatch, larval development and larval mortality assays. All the assays were performed at different concentrations of 2.5mg/ml, 5.0mg/ml and 7.5mg/ml. The nematode third stage larvae were incubated for 24hr, 48hr and 72hr during the larval mortality assay. The present study showed that all the seven-plant species under investigation possessed some anthelmintic activities of varying strength. The highest egg hatch inhibition was observed from the extracts of Senecio barbertonicus with 100 % and the lowest from Dicerocaryum eriocarpum with 2.25 %, for larval development the highest was Gardenia sp 100 % and the lowest Helichrysum sp 26 % at concentration 7.5 mg/mL respectively. Whereas, the highest in larval mortality assay was Senecio barbertonicus and Gardenia sp achieved 100 % after 48hrs and the lowest was Dicerocaryum eriocarpum with49.89 % after 72hrs at concentration 7.5 mg/mL respectively. The use of other different forms of extraction media is recommended because different results can observe and be compared with the results of the present study. Toxicity studies on the indigenous plants observed to have stronger anthelmintic activities would assist in the future recommendation of these remedies for large scale or commercial use as anthelmintic drugs.
Keywords: ethno veterinary medicine, gastrointestinal parasites, anthelmintic
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Sociological perceptions of harvesting, husbandry and sustainable utilization of redundant second-hatched chicks of wild hornbills, eagles and owls at Makuleke Community and the surrounding villagesMakatu, Shumani Elsie January 2000 (has links)
Thesis (M. A. (Sociology)) -- University of the North, 2000 / Refer to the document / NRF (National Research Foundation)
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Various antimalarial strategies in Indonesia to fight Plasmodium falciparum / Différentes stratégies en Indonésie pour combattre Plasmodium falciparumRamadani, Arba Pramundita 20 July 2017 (has links)
Le paludisme demeure un problème de santé publique mondial qui risque de s'aggraver avec la résistance de Plasmodium falciparum aux thérapies combinées à base d'artémisinine (ACT), médicaments antipaludiques les plus récents et les plus efficaces. Mon travail avait pour but de proposer différents axes d'élimination du paludisme en Indonésie. Une première partie a consisté à rechercher de nouveaux médicaments antipaludiques à partir de données ethnobotaniques indonésiennes. Parmi les 25 extraits bruts réalisés à partir de plantes médicinales indonésiennes utilisées traditionnellement dans le traitement du paludisme, sept ont montré une activité antipaludique intéressante (CI50 <5 µg/mL) et certains d'entre eux se sont révélés également actifs sur 2 autres pathogènes Babesia divergens et Leishmania infantum. La deuxième partie de ce travail était axée sur les composés organométalliques synthétiques. Les études de relations structure-activité de ces complexes organométalliques d'or (I) -NHC ont permis de sélectionner un composé actif sur P. falciparum avec une CI50 de 320nM. La troisième partie du travail a été consacrée à l'étude de la résistance de P. falciparum à l'artémisinine et à ses dérivés. La corrélation entre le polymorphisme de PfK13 et la résistance à l'artémisinine a été clairement établie grâce à des études de génétique inverse avec des souches de laboratoire résistantes et sensibles et des isolats cliniques Cambodgiens. Cette résistance a été mise en évidence in vitro par un test de survie parasitaire appelé RSA(0-3h). Par les mêmes méthodes génétique et phénotypique, la cartographie de la distribution du polymorphisme de PfK13 en Indonésie a été réalisée dans la zone de Kupang sur des patients infectés par P. falciparum. Cependant au moment de la collecte des échantillons de sang, la prévalence de P. falciparum a montré une diminution spectaculaire empêchant la poursuite de l'étude clinique. Face au faible nombre de patients admissibles avec un paludisme à P. falciparum, aucun résultat concluant n'a pu être obtenu. En conclusion, les plantes médicinales indonésiennes et les composés synthétiques sont potentiellement intéressants comme point de départ chimique pour de nouveaux médicaments antipaludiques. En ce qui concerne la résistance à l'artémisinine, aucun échec thérapeutique ou parasitologique après traitement par ACT n'a été signalé, pour le moment, en Indonésie. Cependant, les zones de résistance de P. falciparum aux ACT dans le Sud-Est asiatique sont relativement proches et nécessitent, en Indonésie, un suivi des variations de la chimiosensibilité du paludisme à P. falciparum et du polymorphisme de PfK13, responsable de la résistance à l'artémisinine. / Malaria remains a global public health problem and worsening with the resistance of Plasmodium falciparum to Artemisinin-based Combination Therapies (ACTs), the latest and most effective antimalarial drugs. My project aimed to provide insight into malaria elimination in Indonesia. The first part was to look for new antimalarial drugs based on Indonesian ethnobotanical data. Among 25 crude extracts realized on Indonesian traditional medicinal plants, seven showed a good antimalarial activity (IC50 < 5µg/mL) and some of them were also active against Babesia divergens and Leishmania infantum. The second part of the study focused on chemosynthetic organometallic compounds. The structure- activity relationships study on organometallic gold(I)-NHC complexes led to a very active compound on P. falciparum with an IC50 of 320nM. The third part of this work was dedicated to the study of P. falciparum resistance to artemisinin and its derivatives. The correlation between PfK13 polymorphism and artemisinin resistance has been clearly established thanks to reverse genetic with resistant and sensitive laboratory strains and clinical isolates from Cambodia. This resistance was evidenced in vitro throughout a parasite survival assay called RSA(0-3h). By the same genotypic and phenotypic methods, mapping of PfK13 polymorphism distribution in Indonesia was performed in Kupang on P. falciparum malaria patients. However, at the time of P. falciparum blood samples collection, prevalence showed a dramatic decrease hindering the continuation of the clinical study. Facing to the very small number of eligible patients with a P. falciparum malaria, no conclusive results has been obtained. In conclusion, medicinal plants and synthetic compounds are potentially interesting as chemical starting point for new antimalarial drugs. Concerning artemisinin resistance, any treatment failure or delayed cure with ACTs has yet to be reported in Indonesia. However, because Indonesia is relatively close to the Southeast Asian areas of resistance, the possible occurrence of such cases in Indonesia must be anticipated by determining the variations of P. falciparum malaria chemo-sensitivity and by following PfK13 polymorphism, responsible for artemisinin resistance.
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