Twenty nature identical essential oil constituents from seven structural groups were tested for antimalarial, antimicrobial, antioxidant and toxicity properties. The compounds displayed antimalarial activity (IC50 values ranging from 0.9 to 1528.8 μM) with varying toxicity (IC50 values ranging from 5.5 to 1358.4 μM). The data indicates that (-)-pulegone, (E-& Z-)-(±)-nerolidol, linalyl acetate and (+)-α-pinene have the most potent antimalaial activity. Carvacrol (MIC values ranging from <1.66 to 13.3 mM) followed by geraniol (MIC values: 19.5-51.9 mM) displayed the broadest spectrum of antimicrobial activity. The least toxic of the tested compounds, eugenol, was the only compound with antioxidant activity comparable to ascorbic acid. The results demonstrate that the 20 compounds individually display variable biological activity, although further research is required to determine how they may interact when combined.