Table 2.

Antioxidant activity [2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging and β-carotene-linoleic acid models] of 50% methanol extracts of four plants used by Batswana traditional health practitioners to treat skin diseases.

Plant	Plant Part Used	DPPH (EC50 µg/mL)	# Antioxidant (%)
Drimia sanguinea	Bulb	92.6 ± 4.34 d	64.8 ± 1.05 c
Elephantorrhiza elephantina	Rhizome	5.8 ± 0.46 a	84.7 ± 0.59 a
Helichrysum paronychioides	Whole plant	20.1 ± 0.42 b,c	84.4 ± 0.69 a
Senecio longiflorus	Stem and leaves	12.1 ± 0.35 a,b	75.3 ± 0.25 b

Positive controls, Ascorbic acid = 3.9 ± 0.18 µg/mL (for DPPH assay); BHT = 89.8 ± 0.29% (for β-carotene-linoleic acid assay). ^# Extracts and BHT were tested at 400 µg/mL in the β-carotene-linoleic acid assay. In each column, values (mean ± standard error, n = 3) with different letter(s) are significantly (p ≤ 0.05) different based on Tukey’s Multiple Comparison Test.