Abstract
The First Australians had well-developed healing systems. Groote Eylandt inhabitants used a variety of plant species to treat diarrhoea and other gastrointestinal illnesses. This study was undertaken to test, identify, and evaluate traditional medicines to treat these conditions against gastrointestinal bacterial, protozoal, and viral pathogens, as well as against cancer cell proliferation. Six plant species (Buchanania obovata Engl., Casuarina equisetifolia L., Eucalyptus tetrodonta F. Muell., Planchonia careya (F. Muell.) R. Knuth, Terminalia carpentariae C. T. White, and Vigna vexillata (L.) A. Rich.) were selected from a survey of a panel of elders from the Warnindhilyagwa tribe and compared with the published literature. Decoctions prepared according to traditional methods were screened for growth inhibitory activity of a panel of diarrhoea-causing bacterial pathogens by disc diffusion and liquid dilution MIC assays. Inhibitory activity against the gastrointestinal protozoal parasite Giardia duodenalis and antiproliferative activity against human colorectal (Caco2) and cervical (HeLa) cancer cell lines were evaluated using MTS-based colorimetric cell proliferation assays. Preliminary antiviral screening was accomplished using an MS2 bacteriophage plaque reduction assay. Toxicity was evaluated using Artemia franciscana nauplii mortality and HDF cell viability bioassays. All traditional medicines tested inhibited bacterial growth, often with MIC values substantially <1000 μg/mL. T. carpentariae was particularly noteworthy, with MIC values of 230–350 μg/mL against Citrobacter freundii, Salmonella newport, Shigella sonnei, Staphylococcus aureus, and Staphylococcus epidermidis. This species also had MICs 450–950 μg/mL against all other bacterial pathogens. B. obovata Engl. and E. tetrodonta were also good inhibitors of bacterial growth, albeit with substantially higher MIC values than determined for T. carpentariae. The T. carpentariae decoction was also the best inhibitor of MS2 phage replication (IC50 = 427 μg/mL) and Caco2 and HeLa proliferation (IC50 values of 885 and 85 μg/mL, respectively). None of the extracts were particularly strong inhibitors of Giardia duodenalis growth. All decoctions were nontoxic in the Artemia nauplii and HDF cell viability bioassays, indicating their suitability for therapeutic use.
Highlights
Introduction e World HealthOrganization (WHO) has estimated that nearly nine million children under the age of five die every year as a result of diarrhoea [1]
Plants have long been used in traditional healing systems to treat diarrhoea. ese traditional medicines may be given as single-component therapies or they may be prescribed in combination to target the multiple negative effects of Evidence-Based Complementary and Alternative Medicine diarrhoea. e activity of several of the herbal preparations used traditionally to treat diarrhoea and other gastrointestinal diseases has already been validated by rigorous scientific evaluation. is is true for plant medicines used in traditional Indian healing systems [4,5,6] and in traditional Chinese medicine (TCM) [7, 8]
In previous studies in our group, we have studied the antiproliferative activity of plant extracts against Caco2 and human colorectal (Caco2) and cervical (HeLa) (American Type Culture Collection, USA) carcinoma cell lines [25]
Summary
Introduction e World HealthOrganization (WHO) has estimated that nearly nine million children under the age of five die every year as a result of diarrhoea [1]. Plants have long been used in traditional healing systems to treat diarrhoea. E First Australians had a good understanding of the medicinal properties of Australian plants and had used them successfully for at least 50,000 years to treat a variety of illnesses. Little of this information has been recorded as the First Australians did not have a written language. Compounding the problem, the First Australians consist of diverse groups, with individual communities having their own language, culture, customs, and belief systems, as well as their own traditional knowledge. The ethnobotany of the inhabitants of Groote Eylandt has been relatively well recorded, allowing for selection of relevant species to treat microbial pathogens [9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
