E.E. Elgorashi

Isolation of captan from Cyrtanthus suaveolens: the effect of pesticides on the quality and safety of traditional medicine

Bioassay-guided fractionation of dichloromethane extracts of Cyrtanthus suaveolens using the Salmonella/microsome assay (strain TA98) led to the isolation of captan [ N -(trichloromethylthio)cyclohex-4-ene-1,2-diccarboximide] at a concentration of 100mg kg −xa01 of dry plant material. Captan is a pesticide used on a large scale on agricultural and horticultural crops. It is known for its mutagenic, genotoxic and teratogenic effects. Issues of quality and safety of traditional medicinal plants grown commercially in South Africa and the need for the establishment of good agricultural practices are discussed.

Kaempferol, a mutagenic flavonol from Helichrysum simillimum:

Helichrysum simillimum is native to South Africa. It is used for the treatment of coughs, colds, fever, infections, headache, and menstrual pain. Extracts of this species showed mutagenic effects in the Salmonella/microsome assay. The aim of this study was to isolate and determine the mutagenic constituents of H. simillimum. Bioassay-guided fractionation of 90% aqueous methanol extracts, using Salmonella typhimurium TA98, led to the isolation of the flavonol kaempferol.

Effect of Cadmium Accumulation on Anti-Inflammatory Activity in Two Eucomis Species

Eucomis species (Hyacinthaceae) are widely used in South Africa as traditional medicine. The bulbs are used to alleviate a variety of symptoms including pain and inflammation. High levels of cyclooxygenase-1 and -2 (COX-1 and COX-2) inhibitory activity have been associated with certain Eucomis species. The aim of this study was to quantify cadmium (Cd) accumulation and examine its effect on COX-1 and COX-2 anti-inflammatory activity in Eucomis autumnalis and Eucomis humilis. Cadmium application at 2xa0mgxa0L−1 over a 6xa0week period revealed a substantial difference in total Cd accumulation in E. autumnalis and E. humilis (40.2 and 15.3xa0mg Cd kg−1, respectively). When supplied with Cd at 2xa0mgxa0L−1, E. humilis bulbous extracts showed lower inhibitory activity than the control for both COX-1 and COX-2. E. autumnalis bulbous extracts had greater COX-1 activity compared to the control. While COX-2 activity was suppressed. Researchers should be aware of the effect of environmental contaminants when reporting on biological activity of crude plant extracts.