Zulu medicinal plants with antibacterial activity

Aqueous, methanolic and ethyl acetate extracts of 14 plants used in traditi onal Zulu medicine for treatment of ailments of an infectious nature were s creened for antibacterial activity. Most of the activity detected was again st Gram-positive bacteria. Tuber bark extracts of Dioscorea sylvatica had a ctivity against Gram-negative Escherichia coli and extracts of Dioscorea dr egeana, Cheilanthes viridis and Vernonia colorata were active against Pseud omonas aeruginosa. The highest antibacterial activity was found in extracts of C. viridis, D. dregeana, D. silvatica, Melianthus comosus and V. colora ta. In general, methanolic extracts exhibited higher activity than aqueous and ethyl acetate extracts. (C) 2000 Elsevier Science Ireland Ltd. All righ ts reserved.