Anti-Inflammatory Activity of Selected Plants from Saudi Arabia

Thirteen selected Saudi Arabian plants, belonging to seven different families, were tested for possible anti-inflammatory activity using the carrageenin-induced paw edema model in rats. The methanolic extracts of Vernonia schimperi, Trichodesma trichodesmoides var. tomentosum, and Anabasis articulata exhibited the highest anti-infl ammatory activity. The active extracts were further subjected to fractionation with chloroform, ethyl acetate, and n-butanol and tested together with their mother liquor for their anti-infl ammatory activity in the same rat model. The most potent fractions were the n-butanol fractions of Anabasis articulata and Vernonia shimperi and the aqueous mother liquor of Trichodesma trichodesmoides. Nevertheless, the three potent methanolic extracts showed higher anti-infl ammatory activities than their individual fractions. The antioxidant properties were assessed by their in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activities. It was concluded that the anti-inflammatory activity is dependent, at least in part, on the reduction of prostaglandin (PGE2) and tumour necrosis factor-α (TNF-α) levels and cyclooxygenase-2 (COX-2) activity.