Planta Med 2014; 80 - P1L29
DOI: 10.1055/s-0034-1394687

In vitro anti-HIV and -TB activities of Annona muricata and Artemisia afra extracts

M van de Venter 1, M Pruissen 1, T Koekemoer 1, A Sowemimo 2, S Govender 1
  • 1Department of Biochemistry and Microbiology, Nelson Mandela Metropolitan University, Port Elizabeth, 6031, South Africa
  • 2Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria

Mycobacterium tuberculosis and Human Immuno-Deficiency Virus (HIV) have a high prevalence in Africa. The development and spread of drug resistant tuberculosis is a serious problem which is exacerbated by tuberculosis (TB) co-infection in HIV patients. Traditional medicinal plants like Annona muricata and Artemisia afra are used for respiratory ailments and antiviral therapies respectively. The aim of this study was to evaluate Annona muricata (ethanol extract) and Artemisia afra (ethanol and aqueous extracts) for inhibitory activities against M. tuberculosis and HIV. In vitro bioassays for anti-TB activity included: microplate alamar blue assay (MABA) and ρ-iodonitrotetrazolium chloride assays while anti-HIV activity was determined using an HIV-1 reverse transcriptase colorimetric ELISA kit and HIV-1 integrase colorimetric immunoassay. Cytotoxicity of plant extracts were assessed by the MTT assay on Chang Liver and HepG2 cells. Interactions of plant extracts with drug metabolic pathways were evaluated with the Glutathione-S-Transferase and CYP3A4 assay kits. A. muricata ethanol extract exhibited anti-TB activity with MIC 125 µg/mL. Artemisia afra aqueous extract showed weak HIV-1 reverse transcriptase inhibition while the ethanol extracts of A. afra and A. muricata showed inhibition of HIV-1 integrase activity with IC50 s < 100 µg/ml. A. muricata was cytotoxic at IC50 of 30 µg/mL and 77 µg/mL on Chang Liver and HepG2 cells respectively, whilst A. afra aqueous and ethanol extracts were not cytotoxic to both cell lines. A. afra ethanol extract caused a 76.7% inhibition of GST activity at 62 µg/ml, while A. afra (aq) and A. muricata had a slight effect. All extracts inhibited CYP3A4 activity, however the ethanol extracts of A. muricata and A. afra showed greater inhibition than the aqueous A. afra extract (IC50 s 4.5, 25 and 200 µg/ml, respectively). These extracts could be an important source of compounds for treatment of M. tuberculosis and HIV respectively.

Keywords: HIV, Mycobacterium tuberculosis, Annona muricata, Artemisia afra, herb-drug interaction