Abstract
Ricinus communis
has been utilized traditionally as medicine to treat inflammatory related diseases including wounds, sores, and boils. The leaves of
R. communis
were sequentially extracted with
n
-hexane, dichloromethane, acetone, and methanol using serial exhaustive extraction method. Antioxidant activity of all crude extracts was quantitatively measured against 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical molecules using ABTS
+
assay. Cytotoxic effect and anti-inflammatory activity of
R. communis
leaves extracts were evaluated on Human Caucasian skin fibroblast and Raw 264.7 macrophage cell lines, respectively. Methanol extract had the highest percentage free radical (ABTS
+
) scavenging activity of 95% at 2.50 mg/mL, acetone 91%, dichloromethane 62%, and hexane the least (50%). Percentage scavenging activity of ABTS
+
free radical molecules increases with increase in concentrations of the plant extracts. Hexane and dichloromethane extracts had more than 90% cell viability at 100
µ
g/mL after 24 and 48 hours of exposure. Methanol extract had LC
50
of 784
µ
g/mL after 24-hour exposure, hexane had 629.3
µ
g/mL and dichloromethane 573.6
µ
g/mL, and 544.6
µ
g/mL was the lowest with acetone extract. The study present the first report on the scavenging activity of
R. communis
leaf extracts against ABTS
+
radicals and cytotoxic effects on human Caucasian skin fibroblast cell lines.