Evaluation of Athrixia bush tea for cytotoxicity, antioxidant activity, caffeine content and presence of pyrrolizidine alkaloids
Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, Private Bag X04, Onderstepoort, 0110, South Africa; Department of Pharmacology, School of Medicine, Faculty of Health Sciences, PO Box 2034, Pretoria, 0001, South Africa
McGaw, L.J., Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, Private Bag X04, Onderstepoort, 0110, South Africa; Steenkamp, V., Department of Pharmacology, School of Medicine, Faculty of Health Sciences, PO Box 2034, Pretoria, 0001, South Africa; Eloff, J.N., Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, Private Bag X04, Onderstepoort, 0110, South Africa
In South Africa, Athrixia phylicoides DC. (bush tea) is widely used as a beverage, cough remedy and purgative. The commercialization of this tea in a similar vein to rooibos (Aspalathus linearis), is being considered. Traditional infusions and decoctions, as well as water and ethanol extracts, were prepared and screened. A related species, Athrixia elata Sond. (daisy tea), was included in many of the assays as a comparison. Extracts of Athrixia phylicoides and Athrixia elata were tested for toxic effects to brine shrimp larvae and the Vero kidney cell line. In both assays, the traditional preparations and aqueous extracts had little effect, but the ethanol extracts were relatively toxic. Antioxidant activity comparable to that found in rooibos was established. No detectable levels of caffeine were present in the Athrixia extracts following analysis using TLC and I/HCl spray reagent. Neither screening using spectrophotometry nor confirmation using gas chromatography-mass spectrometry analyses showed evidence of pyrrolizidine alkaloids in Athrixia phylicoides. Although a wider range of studies needs to be conducted prior to commercialization, these results support the development of bush tea as a healthy alternative to caffeine-containing beverages. © 2006 Elsevier Ireland Ltd. All rights reserved.
antioxidant; Athrixia extract; berberine; caffeine; cytotoxic agent; podophyllotoxin; pyrrolizidine alkaloid; unclassified drug; animal cell; animal experiment; Artemia; article; Asteraceae; Athrixia; Athrixia elata; Athrixia phylicoides; drug cytotoxicity; drug isolation; nonhuman; Vero cell; Animals; Antioxidants; Artemia; Beverages; Caffeine; Cell Line; Drug Toxicity; Humans; Kidney; Plant Extracts; Plants, Medicinal; Pyrrolizidine Alkaloids; Solvents; South Africa; Artemia; Aspalathus linearis; Asteraceae; Athrixia