CANDIDATE MEDICINAL PLANT SPECIES OF DJIBOUTIAN PHARMACOPEIA FOR TESTING PHARMACOLOGICAL ACTIVITIES ON COMMON MICROBIAL DISEASES Original Article FATOUMA MOHAMED ABDOUL-LATIF 1* , DJALTOU ABOUBAKER OSMAN 1 , ABDIRAHMAN ELMI FOURREH 1 , ALSHAIMAA HASSAN-ABDALLAH 1 , ALI MERITO 1 , SOUAD HASSAN 1 , ZEMEDE ASFAW 2 , ENSERMU KELBESSA 2 1 Medicinal Research Institute, Centre d’Etudes et de Recherche de Djibouti, Route de L’aéroport, BP: 486 Djibouti, Djibouti, 2 Received: 19 Mar 2015 Revised and Accepted: 12 Aug 2016 Department of Plant Biology and Biodiversity Management, College of Natural Sciences, Addis Ababa University, P. O. Box 3434, Addis Ababa, Ethiopia Email: fatouma_abdoulatif@yahoo.fr ABSTRACT Objective: The aim of the study was to conduct an ethnobotanical study focused on the medicinal plants used in Randa (Djibouti) for testing pharmacological activities on common microbial diseases. Methods: Plant Ratio (PR), Index of Performance (IP) and the high Informant Consensus Factors (ICF) were calculated to select candidate medicinal species with a pharmacological potential. Results: From this previous work, it was found that the high Informant Consensus Factors, ICF (0.82) for the category of microbial diseases turned out to merit further perusal. The findings particularly gave an imminent insight that stimulated additional investigations and analyses. Different factors, including Plant Ratio (PR) and Index of Performance (IP) were employed for comparison leading to the selection of 18 candidates species, for subsequent pharmacological screening, and testing for antimicrobial activities. Comparison of the information with that accessed from the literature implicitly hinted that the Djiboutian traditional medical system shares much in common with other traditional medical systems. At least six out of the 18 species have not been pharmacologically tested before. Conclusion: The comparison of differents factors (IP2, PR and FL’) of plants screening have showed that 18 plants species of Randa region, have good healing potential for infectious diseases. This may inspire continued research to build a comprehensive ethnobotanical and ethnopharmacological profiles of the species anticipated to be of the most promising potential for Djibouti and beyond. Keywords: Traditional medicinal plants, Djibouti, Randa, Statistical analysis © 2016 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4. 0/) DOI: http://dx.doi.org/10.22159/ijpps.2016v8i10.5788 INTRODUCTION Many clinically useful prescription drugs have originated from traditional medicinal plants. Since there are many traditional medicinal plants widely used by the society in Randa (Djibouti), it is worth subjecting these plants to investigation for the discovery of drugs with an anticipation of obtaining new bioactive substances. Randa with its unique climate and vegetation [1] may disclose some endemic species which have not been tested previously. Poorly developed prevention system and resistance to drugs are the two main factors aggravating microbial infections in Djibouti [2-4]. This is related to the high prevalence in Djibouti of infectious diseases, probably caused by poverty and the general unhygienic conditions observed in many parts of Randa region. After identifying traditional medicinal plants in Randa (Djibouti) by interviewing and conducting discussions with informants, priority diseases/disease categories were screened [5, 6]. Almost 20% of the medicinal plants recorded were those used by the people against infections [1]. This study aims at a selection of medicinal plants used for the care of cases of infectious diseases, and which have pharmacology properties. To further strengthen the validity of the present work, a critical literature review was made followed by a simple comparison of the selected medicinal plants with the previous data gathered from the literature. MATERIALS AND METHODS As mentioned previously [1], the ethnobotanical study was conducted in Tadjourah District of Randa region in Djibouti, where 184 informants were interviewed from July 2010 to February 2011. In this first study, the Informant Consensus Factor (ICF) was calculated for each ailment category to identify the agreements of the informants on the reported cures for the group of diseases [7, 8] and the Fidelity Level (FL’) Index shows the percentage of informants claiming the use of a certain plant for the same ailment. We introduced additional statistical analysis for identifying candidate plants. Plant ratio (PR) Plant ratios towards a disease indicating the top ranking plants for a given disease, was calculated as PR = (Ip/It) ×100, where Ip is the number of informants who independently indicated the use of a species for the same ailment and It is the total number of informants who mentioned any plant for the same disease. Ratios were rejected if Ip (the number of informants) that mentioned any plant for a particular disease is less than 15 in order to make certain that plants with higher consensus among community members are used for the analysis. Index of performance (Ip2) [9] To illustrate the selectivity of a plant for a specific ailment, a comparison was made between the expected and the observed values of the proportion of citation of a plant for a speci fic disease. The difference (P1–P2) between the two proportions was then used to de fine an Ip2 performance index which ranged from 0 to 3 according to an arbitrary scale rationalized for the purpose. The calculation P1–P2 was made as follows: P1 = C1/C2 P2 = C3/C4 C1 = number of citations of a plant A for treating a specific disease B, International Journal of Pharmacy and Pharmaceutical Sciences ISSN- 0975-1491 Vol 8, Issue 10, 2016