Evaluation of anti-acne activity of selected Sudanese medicinal plants

Acne vulgaris is the most common skin disease in the world, and the number of antibiotics resistant to acne-inducing bacterial strains has been increasing in the past years. Natural substances from plants are promising candidates to treat this disease. The methanol and 50 % (v/v) ethanol extracts of 29 plant species traditionally used in Sudan for treatment of a variety of diseases were tested in vitro for their potential anti-acne activity. The activities of these extracts were determined using an antibacterial assay against Propionibacterium acnes, a lipase inhibitory assay, and l,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay. The results showed that methanol and 50 % ethanol extracts of Terminalia laxiflora Engl & Diels wood exhibited good antibacterial activity (minimum inhibitory concentration 0.13 mg/ml). The 50 % ethanol extracts of Abrus precatorius L. seed, T. laxiflora Engl & Diels and methanol extract of Acacia nilotica (L.) pods showed lipase inhibitory activity more than 70 % at 500 μg/ml. The methanol extracts of A. nilotica (L.) pods showed the best DPPH radical scavenging activity (IC50 1.32 μg/ml). Total phenolic, flavonoid and total tannin contents of selected plant extracts shown anti-acne activities were investigated. Almost all selected extracts contained phenolic compound. The highest level of flavonoids (38.87 μg/mg) was detected in T. brownii bark, whereas the highest amount of tannin was detected in A. nilotica (L.) bark (88.01 %).