title: A comparative study of the antimicrobial and phytochemical properties between outdoor grown and micropropagated Tulbaghia violacea Harv. plants.
abstract: OBJECTIVE
  The study aimed to compare the antimicrobial and phytochemical properties of in vitro cultured and outdoor grown Tulbaghia violacea plants in the quest to validate the use of micropropagated plants as alternatives to outdoor grown plants in traditional medicine. Tulbaghia violacea is used extensively in South African traditional medicine for HIV/AIDS patients and in the treatment of gastrointestinal ailments, asthma, fever and tuberculosis.
  
  
  METHODS
  Extracts of micropropagated and outdoor grown Tulbaghia violacea plants were evaluated for their antibacterial and antifungal activities against Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus and a fungus Candida albicans using microdilution methods. Saponins and phenolic compounds including condensed tannins, gallotannins and flavonoids were quantitatively determined using spectrophotometric methods. A qualitative test for saponins was also carried out.
  
  
  RESULTS
  The petroleum ether (PE) extracts of micropropagated plants and dichloromethane (DCM) extracts of outdoor grown plants showed good antibacterial activity, each against two bacterial test strains. PE extracts of micropropagated plants showed the best antibacterial activity with a minimum inhibitory concentration (MIC) of 0.39 mg/ml against Bacillus subtilis. Good MIC (<1mg/ml) and minimum fungicidal concentration (MFC) values of 0.78 mg/ml were only obtained in DCM extracts of outdoor grown plants. MIC and MFC values for water and ethanol extracts of both micropropagated and outdoor grown plants were similar and in the range 3.125-12.5mg/ml. Total phenolics, gallotannins, flavonoids and saponins were significantly higher in micropropagated plants than in outdoor grown ones. In all cases, the amounts of phytochemical compounds in micropropagated plants were more than twice that of outdoor grown plants except for condensed tannins.
  
  
  CONCLUSIONS
  The results form a good basis for the use of Tulbaghia violacea micropropagated plants as a complement to the outdoor grown plants in traditional medicine.
authors.affiliation: Research Centre for Plant Growth and Development, School of Biological and Conservation Sciences, University of KwaZulu-Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa.
authors.forename: B
authors.initials: B
authors.lastname: Ncube
authors.forename: V N P
authors.initials: VN
authors.lastname: Ngunge
authors.forename: J F
authors.initials: JF
authors.lastname: Finnie
authors.forename: J
authors.initials: J
authors.lastname: Van Staden
mesh_terms: D000473:Alkanes / Q000737:chemistry; D000490:Allium / Q000737:chemistry* / Q000254:growth & development; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D007711:Klebsiella pneumoniae / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000032:analysis; D010936:Plant Extracts / Q000494:pharmacology*; D012503:Saponins / Q000032:analysis; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000473:Alkanes; D000890:Anti-Infective Agents; D010636:Phenols; D010936:Plant Extracts; D012503:Saponins; C004544:naphtha