Table 2.

Antiproliferative activity of the synergistic combination and each component

Sample	IC50a ± SDb (µg ml)
Heteropyxis natalensis (µg ml− 1)	35.56 ± 0.16
Melaleuca alternifolia (% v/v)	> 5 × 10− 2
Mentha piperita (% v/v)	1 × 10− 2 ± 4 × 10− 4
Camellia sinensis (µg ml− 1)	> 400c
Synergistic plant combination: Heteropyxis natalensis at 62.5 µg ml− 1 Melaleuca alternifolia at 0.001% v/v Mentha piperita at 0.001% v/v Camellia sinensis at 40 µg ml− 1	> 400
Actinomycin D (µg ml− 1)	1.6 × 10− 3 ± 2.8 × 10− 4

^aIC₅₀: 50% inhibitory concentration of viability; ^bSD: standard deviation; ^cThe highest concentration tested