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The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol) obtained from Brazilian Drosera species (D. communis, D. montana var. montana, D. brevifolia, D. villosa var. graomogolensis, D. villosa var. villosa, Drosera sp. 1, and Drosera sp. 2 ) were tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecium (ATCC23212), Pseudomonas aeruginosa (ATCC27853), Escherichia coli (ATCC11229), Salmonella choleraesuis (ATCC10708), Klebsiella pneumoniae (ATCC13883), and Candida albicans (a human isolate). Better antimicrobial activity was observed with D. communis and D. montana var. montana ethyl acetate extracts. Phytochemical analyses from D. communis, D. montana var. montana and D. brevifolia yielded 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin); long chain aliphatic hydrocarbons were isolated from D. communis and from D. villosa var. villosa, a mixture of long chain aliphatic alcohols and carboxylic acids, was isolated from D. communis and 3b-O-acetylaleuritolic acid from D. villosa var. villosa.

Species of the carnivorous genus Drosera L. have long been a source of valuable natural products. The various phytochemicals characteristic of these species, particularly 1,4-naphthoquinones and flavonoids, have contributed to the diverse utilization of sundews in traditional medicine systems worldwide. A growing number of studies have sought to investigate the comparative phytochemistry of Drosera species for improved sources of pharmaceutically important compounds. The outcomes of these studies are here collated, with emergent trends discussed in detail. Important factors which affect production of secondary metabolites in plants are critically examined, such as environmental influences and in vitro culture, and recommendations subsequently presented based on this. Explicitly, the current review aims to i) present an updated, comprehensive listing of the phytochemical constituents of the genus (including quantitative data where available), ii) summarize important factors which may influence the production of phytopharmaceuticals in plants, and iii) recommend guidelines for future research based on the above, including improved standardization and quality control. We have also included a section discussing future perspectives of research on Drosera spp. based on three different research lines i) the potential to produce much needed lead compounds for treatment of tuberculosis, ii) the potential role of anthocyanins in nitrogen transport, and iii) research into 'Natural Deep Eutectic' solvents produced by Drosera spp. in the droplets or 'dew' employed to capture insect prey., (Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.)