Medicinal plants are used in traditional medicine throughout the world. In addition to this, certain communities consider medicinal plants to be safer than drugs and able to treat more than one ailment. This study aimed to evaluate the cytotoxicity and anti-inflammatory effects of Euclea crispa (leaf), Eulea natalensis (leaf), Schkuhria pinnata (leaf), Ziziphus mucronata (leaf), Ziziphus mucronata (fruits), Lippia javanica (leaf), Vernonia oligocephala (leaf), Clerodendrum myricoides (leaf), and Erythrina lysistemon (leaf) in C2C12, and RAW 264.7 cells. Plants were extracted with 90% methanol (1 g/10 ml) and diluted in distilled water to give a final concentration of 10 mg/ml. C2C12, and RAW 264.7 cells were treated for 24 h with various concentrations of plant extracts (10 -1000 µg/ml). Cytotoxicity was evaluated with Alamar Blue and crystal violet cell viability assays. RAW 264.7 cells were stimulated with lipopolysaccharide (LPS) to produce nitric oxide (NO). Thereafter, the antiinflammatory effect of the plant extracts was assessed by their ability to inhibit NO production, using the Griess reagent assay. None of the plants extracts demonstrated cytotoxic effects at the concentrations used against RAW 264.7 cells with LC 50 value >1000 µg/ml. However, a degree of cytotoxicity in all plant extracts against C2C12 cells in higher concentrations was observed with LC 50 <1000 µg/ml. All plant extracts demonstrated some degree of anti-inflammatory effect. However, plant extracts exhibited marked anti-inflammatory activities. These were Clerondendrum myricoides (35% -89%), Lippia javanica (26% -77%), Erythrina lysistemon (23% -76%), Schkuhria pinnata (27% -65%), and Vernonia oligocephala (16% -58%) with IC50 value >1000 µg/ml. The present findings suggest that these plants' extracts may serve as a promising therapeutic agent for inflammatory diseases and authenticates their use in traditional medicine.

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