Table of Contents Page Acknowledgements
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TABLE OF CONTENTS PAGE ACKNOWLEDGEMENTS.....................................................................................................i LIST OF TABLES...............................................................................................................ii LIST OF FIGURES............................................................................................................iii ABREVIATIONS...............................................................................................................iv ABSTRACT.........................................................................................................................v 1. INTRODUCTION...........................................................................................................1 2. OBJECTIVES..................................................................................................................8 2.1. General objectives......................................................................................................8 2.2. Specific objectives.....................................................................................................8 3. MATERIALS AND METHODS.....................................................................................9 3.1. Ethnobotanical study.................................................................................................9 3.1.1.The study area...................................................................................................11 3.1.2. Data collection method 3.2. Toxicity and Antimalarial studies...........................................................................12 3.2.1. Basis for the selection of plant species used for in vivo antimalarial study................................................................................12 3.2.2. Description of plant species used in the study.................................................12 3.2.3. Plant extraction................................................................................................13 3.2.4. Toxicity test.....................................................................................................13 3.2.5. In vivo antimalarial test....................................................................................13 3.2.6. Data analysis....................................................................................................14 4. RESULTS......................................................................................................................16 4.1. Ethnobotanical study results..............................................................................16 4.2. Toxicity and antimalarial study results..............................................................21 5. DISCUSSION................................................................................................................26 6. CONCLUSION..............................................................................................................34 7. RECOMMENDATIONS...............................................................................................35 8. REFERENCES..............................................................................................................37 9. ANNEXES.....................................................................................................................44 LIST OF FIGURES PAGE Figure 1. Map of the Afar National Regional state of Ethiopia showing the study area, the Awash Fentale District……………………………………….10 Figure 2. Plant parts utilized in management of malaria in Awash Fentale District…….......................................................................................................20 Figure 3. Habit of the plant species used in management of malaria in Awash Fentale District………………………………………………………..20 Iii LIST OF TABLES PAGE Table 1. Antimalarial Plant species collected from Awash Fentale District of the Afar region of Ethiopia …………………….....................17 Table 2.list of plant species used for malaria treatment by frequency in Awash Fentale District……………………………………………......18 Table 3.Plant species commonly used in the traditional treatment of malaria by kebeles in Awash Fentale District…………………………………....19 Table 4.Body weight of P.berghi infected mice after the administration of Aloe sp. and C. rotundifolia aqueous extracts………………………….....21 Table 5.Body weight of P.berghi infected mice after the administration of Aloe sp. and C. rotundifolia ethanol extracts.............................................22 Table 6. Activity of water and ethanol extracts of Aloe sp. leaves against Plasmodium berghei in mice…………………………............................24 Table 7. Activity of water and ethanol extracts of Cadaba rotundifolia leaves against Plasmodium berghei in mice....................................................... 26 ii ABSTRACT Ethnobotanical study of antimalarial medicinal plants in Awash Fentale district was carried out between November and December 2007. Semi-structured interview was used to gather medicinal plant knowledge of the Afar people residing in Awash Fentale District. Sampled informants were interviewed about their knowledge of use of medicinal plants, plant parts used, practices and management systems against malaria. The local names of medicinal plants and their habits were also recorded. During the survey, a total of 19 antimalarial medicinal plant species were reported. These plants were collected from four kebeles in the study area. With regard to preparations, remedies are mainly done by crushing plant parts to make infusion or decoction with cold or hot water. Oral application is widely used in almost all practitioners. The leaf is the most common part of the plants used (44 %) followed by stem (22 %). Shrubs and trees were plants with higher frequencies to treat malaria accounting for 63 % and 21 % of the plants, respectively. Crude water and ethanol extracts obtained from the leaves of Aloe sp. and Cadaba rotundifolia were tested in vivo for antimalarial activity on a total of 160 Swiss albino mice. Each mouse in the study was infected intraperitonially with blood samples taken from mice previously infected with Plasmodium berghei (chloroquine sensitive) after dilution so that 0.2ml contained 106-107 infected erythrocytes. The extracts were given orally to the infected mice starting from three hours following infection. Antimalarial activity was evaluated by taking blood smears on the fifth day of infection. This study showed that ethanol extracts obtained from the leaves of C. rotundifolia and Aloe sp. suppressed parasitemia significantly (53.73% and 49.07%, respectively) at 900mg/kg. However, aqueous crude extracts obtained from the leaves of both C. rotundifolia and Aloe sp. (40.8% and 31.7%, respectively) did not show significant suppressive effect on parasitemia as compared to their ethanol extracts. The non-toxic properties of these plants up to a dose of 1500mg/kg was also revealed. Key words: Aloe sp., Antimalarial activity, Cadaba rotundifolia, Ethnobotany, In vivo, Medicinal plants, Plasmodium berghei. V ADDIS ABABA UNIVERSITY SCHOOL OF GRADUATE STUDIES Ethnobotanical survey of plants used to treat malaria in the Awash –Fentale District of the Afar Region of Ethiopia and in vivo screening of some selected plants for their antimalarial activities. BY NEGA ALELIGN Thesis Submitted to the Research and Graduate Studies of the Addis Ababa University in Partial Fulfillment of Requirements of the Degree of Master of Science in Biology (Biomedical sciences) JULY, 2008 ADDIS ABABA UNIVERSITY SCHOOL OF GRADUATE STUDIES Ethnobotanical survey of plants used to treat malaria in the Awash- Fentale District of the Afar Region of Ethiopia and in vivo screening of some selected plants for their antimalarial activities. By Nega Alelign A Thesis Presented to the School of Graduate Studies of the Addis Ababa University in Partial Fulfillment of the Requirements for the Degree of Master of Science in Biology Approved by Examining Board: Dr. Mirutse Giday (Advisor) Ato Abebe Animut (Advisor) Dr. Tilahun Teklehaymanot (Advisor) Dr. Yalemtsehay Mekonnen (Examiner) Ato Mengistu Legesse (Examiner) (Chairman) July, 2008 Declaration I, the undersigned, declare that this thesis is my own work. It has not been presented in other universities, colleges or institutions, seeking for similar degree or other purposes. All sources of materials used for the thesis have been duly acknowledged. Name: Nega Alelign Signature: Date: ACKNOWLEDGEMENTS I deeply express my gratitude to my advisors, Dr. Mirutse Giday, Ato Abebe Animut and Dr. Tilahun Teklehaymanot for initiating the research problem and for their keen interest in supervising and giving comments during my work. I am also grateful to thank Ato Engdawork Mulleta , for his unreserved assistance in plant material extraction, W/o Kokebe G/Michael and W/o Baysasaw G/Medhin for their help in laboratory work. Ato Girma Kebede for his ethausticated help in preserving the experimental mice and secretaries of the ALIPB for their help during the study. I would also like to thank the Aklilu Lemma Institute of Pathobiology for providing me financial support for my research work. Ato Mengistu Legesse is also thanked for his help in facilitating the laboratory work. My thanks also go to my friends Ibrahim Issa and Abrham Getu for their encouragement during my stay in the university. Finally, I would like to extend my great appreciation to my father Ato Alelign Yesuf (May Allah gives His Mercy) who