Antimicrobial activity of selected Iranian medicinal plants against a broad spectrum of pathogenic and drug multiresistant micro-organisms.

The antimicrobial activities of 44 methanolic extracts from different parts of Iranian indigenous plant species used in traditional medicines of Iran were tested against a panel of 35 pathogenic and multiresistant bacteria and 1 yeast. The antimicrobial efficacy was determined using Müller-Hinton agar in Petri dishes seeded by a multiple inoculator and minimal inhibition concentration (MIC) method. The 21 most active extracts (MIC < 0·3 mg ml(-1) for one or several micro-organisms) were submitted to a more refined measurement. The best antibacterial activity was obtained by 10 plants. Microdilution assays allowed to determinate the MIC and MBC of the 21 most active extracts. The lowest achieved MIC value was 78 µg ml(-1), with 4 extracts. This work confirms the antimicrobial activity of assayed plants and suggests further examination to identify the chemical structure of their antimicrobial compounds. Significance and impact of the study: This study describes the antimicrobial screening of Iranian plant extracts chosen according to traditional practice against 36 microbial strains, from reference culture collections or recent clinical isolates, and enables to select 4 candidates for further chemical characterization and biological assessment: Dorema ammoniacum, Ferula assa-foetida, Ferulago contracta (seeds) and Perovskia abrotanoides (aerial parts). This may be useful in the development of potential antimicrobial agents, from easily harvested and highly sustainable plant parts. Moreover, the weak extent of cross-resistance between plant extracts and antibiotics warrants further research and may promote a strategy based on less potent but time-trained products.

Amazonian plants from Peru used by Quechua and Mestizo to treat malaria with evaluation of their activity.

Indigenous Quechua and Mestizo populations from distinct areas in Loreto, Peru, were interviewed about traditional medication for the treatment of malaria. An ethnographic survey concerning the native theory of illness aetiology in the specific case of malaria permitted the elaboration of an efficient ethnopharmacological enquiry. The survey took place on three main zones corresponding to villages on the Napo and the Pastaza rivers (for the Quechua), and in the surroundings of Iquitos (for the Mestizos) and led to the collection of 14 plants. Serial extractions in hexane, dichloromethane, and methanol were performed on the different parts of the plants collected. The extracts were then tested for antiplasmodial activity in vitro. Seven plants displayed antiplasmodial activity (IC(50) from 2 to 25 microg/mL) and usually low cytotoxicity, indicating their antiplasmodial specificity. The results give scientific validation to the traditional medical knowledge of Quechua and Mestizo populations from Loreto and confirm a source of potentially active plants.