J Ethnopharmacol. 1980 Sep; 2(3): 279-90.

Phototoxic and antibiotic activities of plants of the Asteraceae used in folk medicine.

Wat CK, Johns T, Towers GH.

Ethanolic extracts of forty-four commercial herbal drugs and two fresh plants used in folk medicine, all species of the Asteraceae, were examined for their phototoxic and antibiotic activities against Escherichia coli, Saccharomyces cerevisiae and Candida albicans. Twenty samples were found to be active as either phototoxic and/or antibiotic agents and their phototoxic effects correlate with the presence of polyacetylenes and thiophenes.