Background: Arctotis arctotoides
,
Gasteria bicolor
and
Pittosporum viridiflorum
are commonly used in the Eastern Cape, South Africa by traditional
healers for the treatment of opportunistic fungal infections in HIV/AIDS patients. Unfortunately, there is a dearth of published data regarding the
toxicity of the selected plants, despite the fact that experimental screening of toxicity is crucial to guarantee the safety of the users.
Materials and Methods: Therefore, it was decided to evaluate the cytotoxicity of the hexane and acetone extracts of the medicinal plants against the
Chang Liver cell line using the
in vitro MTT assay. Different concentrations of the extracts were added into 24-hour cultured cells and incubated for
72 hours under specific condition (37 °C, 5% CO
2). Cell survival was evaluated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium
bromide (MTT) assay.
Results: Depending on the dosage and duration of treatment, the cytotoxic effects of
Gasteria bicolor and
Pittosporum viridiflorum were considered
relatively weak (but not entirely absent) and less of a toxicity risk.
Arctotis arctotoides extracts were the most toxic both in terms of IC
50 values as
well as the steeper slope of the dose response curve. The IC
50 values for the acetone and hexane extracts of this plant were 17.4 and 12.4 μg/ml
respectively.
Conclusion: These relatively low values raise concern for potential hepatotoxic effects and deserve further investigation or at least a warning to
potential users.
