title: Antimicrobial activities of the methanol extract and compounds from the twigs of Dorstenia mannii (Moraceae).
abstract: BACKGROUND
  Dorstenia mannii (Moraceae) is a medicinal herb used traditionally for the treatment of many diseases. In the present study, the methanol extract of D. mannii and nine of its isolated compounds, namely dorsmanin A (1), B (2), C (3), D (4), E (6), F (7), G (8) dorsmanin I (9) and 6,8-diprenyleriodictyol (5), were tested for their antimicrobial activities against yeast, Mycobacteria and Gram-negative bacteria.
  
  
  METHODS
  The microplate alamar blue assay (MABA) and the broth microdilution method were used to determine the minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) of the above extract and compounds on a panel of bacterial species.
  
  
  RESULTS
  The results of the MIC determinations demonstrated that the methanol extract as well as compounds 3 and 8 were able to prevent the growth of all the fourteen studied microorganisms within the concentration range of 4 to 1024 μg/ml. The lowest MIC value for the methanol extract (64 μg/ml) was obtained on Candida albicans. The lowest value for individual compounds (4 μg/ml) was recorded with compounds 3 on Pseudomonas aeruginosa PA01 and 7 on Eschericia coli ATCC strain. The MIC values recorded with compounds 3 on P. aeruginosa PA01, 6 on C. albicans,7 on P. aeruginosa PA01 and K. pneumoniae ATCC strain and C. albicans,and 8 on P. aeruginosa PA01, PA124, P. stuartii, M. tuberculosis MTCS1 were lower than or equal to those of the reference drugs. MMC values not greater than 1024 μg/ml were recorded on all studied microorganisms with compounds 3 and 8.
  
  
  CONCLUSIONS
  The overall results of the present investigation provided evidence that the crude extract of D. mannii as well as some of its compounds such compounds 3 and 8 could be a potential source of natural antimicrobial products.
authors: Department of Biochemistry, Faculty of Science, University of Dschang, Cameroon. armkuete@yahoo.fr
authors: Armelle T
authors: AT
authors: Mbaveng
authors: Victor
authors: V
authors: Kuete
authors: Bathelemy
authors: B
authors: Ngameni
authors: Veronique P
authors: VP
authors: Beng
authors: Bonaventure T
authors: BT
authors: Ngadjui
authors: Jacobus J Marion
authors: JJ
authors: Meyer
authors: Namrita
authors: N
authors: Lall
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D029586:Moraceae / Q000737:chemistry*; D009161:Mycobacterium / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018547:Plant Stems / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D005419:Flavonoids; D010936:Plant Extracts; C478608:dorsmanin C; C478609:dorsmanin F; C576546:dorsmanin G