Ethnobotanical study and phytochemical screening of six medicinal plants used in traditional medicine in the Northeastern Sahara of Algeria (area of Ouargla)

An ethnobotanical survey was undertaken to collect information from traditional healers on the use of plants (Atriplex halimus L., Searsia tripartita (Ucria) Moffett, Limoniastrum guyonianum Durieu ex Boiss., Haplophyllum tuberculatum Juss., Tamarix gallica L. and Nitraria retusa (Forssk.) Asch.) in folkloric medicine of Ouargla (Algeria), using a predesigned questionnaire. The studied plants were screened for the presence of secondary metabolites. The traditional healers in the study area used the investigated species for the treatment of various diseases. The average of the informant consensus factor (FIC) value for all ailment categories was 0.93, with the highest number of species being used for digestive problems (449) followed by dermatological symptoms (154) and nervous disorders (144). These pathologies were mainly treated by leaves in the form of decoction, representing the dominant formulation. The oral administration which regrouped the major form of usage, which was in form of drink, was most exercised. The phytochemical analysis showed the presence of polyphenolic compounds and saponins in almost all tested plants. For the other metabolites classes, results varied between plants. The multi-uses of species demonstrated the importance of these plants and the diversity of the ancestral knowledge. Key words: Ethnobotanical study, spontaneous plants, traditional pharmacopeia, phytochemical analysis, Ouargla.