Abstracts (IC50 =92 μg/ml). All the other extracts showed little or no activity. Hexane extract was the only extract that showed reverse transcriptase extract inhibitory effect with an IC50 of 74 μg/ml. Antigonococcal and cytotoxicity investigations are underway. The preliminary results support the use of the herbal mixture for the treatment of sexually transmitted diseases by traditional healers. doi:10.1016/j.sajb.2017.01.126 355 considered the former taxon to possibly be conspecific with P. amatymbica. Polygala nodiflora is also classified as a Data Deficient Taxon (DDT), which means it is difficult to ascertain the species’ status when assessing conservation status of a taxon. This study was based on morphological character examination and comparison of the two species using herbarium specimens. Field studies to rediscover the species at the type locality area was also undertaken. The results indicate that P. nodiflora is distinctly a separate species from P. amatymbica. The presentation also discusses the conservation status of P. nodiflora. doi:10.1016/j.sajb.2017.01.128 Studies on the medicinally important southern African Rhynchosia species (Phaseoleae, Fabaceae): Their taxonomy, ethnobotany, phytochemistry and antimicrobial activity M.S. Mothogoane, A.N. Moteetee Department of Botany and Plant Biotechnology, University of Johannesburg (APK Campus), PO Box 524, Johannesburg 2006, South Africa E-mail address: M.Mothogoane@sanbi.org.za (M.S. Mothogoane) Since Baker’s revision of the South African species of Rhynchosia Lour. (Fabaceae) in 1923, the number of species has risen from 59 to 72. Taxonomic studies in the genus in southern Africa have mainly been at sectional level, but studies on the type section have lagged behind. It is evident that due to its morphological variation, this section comprises several complexes. Work is ongoing to identify and study these complexes; however previous reports based on the flora of Tropical Africa have identified three complexes which taxonomically pose “maximum difficulty”. These are the R. minima (L.) DC., R. totta (Thunb.) DC. and R. viscosa (Roth) DC. complexes, the latter does not occur in South(ern) Africa, while a revision of the R. totta complex has been completed. A number of species in the genus are also recorded to be used traditionally for medicinal purposes, however, the information is scattered. In addition, these species are yet to be subjected to any biological activity assays and their chemical properties are also not known. The aim of this study therefore is to conduct taxonomic studies of South African Rhynchosia Lour. species used traditionally for medicinal purposes, with special emphasis on a revision of the Rhynchosia minima (L.) DC. group. The study will also evaluate ethnobotanical uses, phytochemical properties, as well as antimicrobial activity of these species. In this presentation, progress made thus far is reported. doi:10.1016/j.sajb.2017.01.127 Taxonomic study of Polygala nodiflora and its conservation status M.S. Mothogoanea, N.A. Nyilab a South African National Biodiversity Institute, Pretoria National Botanical Gardens, National Herbarium, Private Bag X101, Silverton 0184, South Africa b Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, UNISA Science Campus, Florida 1710, Johannesburg, South Africa E-mail address: M.Mothogoane@sanbi.org.za (M.S. Mothogoane) Polygala nodiflora Chodat was first described by in 1913 from a single specimen. This specimen was collected in the Lydenburg district in Mpumalanga, South Africa. The species is most closely related to P. amatymbica Eckl. & Zeyh., which is widely distributed from the Eastern Cape upwards along the eastern parts of South Africa to Limpopo Province. The latest revision of the genus Antimicrobial activity and safety of two Newtonia spp. (Fabaceae) with potential for alleviating infectious diarrhoea K.E. Motlhatlego, J.N. Eloff, L.J. McGaw Phytomedicine Programme, Department of Paraclinical Sciences, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa E-mail address: katlego.motlhatlego@gmail.com (K.E. Motlhatlego) Diarrhoea may be caused by infection with microbial pathogens, intestinal inflammation, food allergy and drug intolerance. Diarrhoea causes high mortality and morbidity especially in children and immunocompromised patients. Newtonia buchananii (Baker) G.C.C.Gilbert & Boutique and Newtonia hildebrandtii var. hildebrandtii were selected based on good preliminary antimicrobial activity and low cytotoxicity. Newtonia species are used traditionally in southern Africa to treat stomachache and infectious diseases. This study aims to evaluate the efficacy of these plants against diarrhoea by evaluating antimicrobial activities and safety of the leaf, stem and seed extracts. The serial microdilution method was used to determine minimum inhibitory concentrations (MIC) and bioautography was used to detect number of antimicrobial components against three Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus and Enterococcus faecalis), three Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium) and two fungi (Candida albicans and Cryptococcus neoformans). Cytotoxicity against Vero cells using the MTT assay was evaluated. Newtonia buchananii had strong antimicrobial effect against P. aeruginosa with MIC=20 μg/ml and moderate activity of 40 μg/ml against B. cereus while N. hildebrandtii had the highest antibacterial activity against Bacillus cereus with MIC=80 μg/ml. MIC values of N. buchananii and N. hildebrandtii against both fungi was 160 and 310 μg/ml respectively. The extracts were relatively nontoxic with IC50 values of 30-750 μg/ml. Selectivity index values as high as 25 were reached. The acetone extracts of both N. buchananii and N. hildebrandtii had good antimicrobial activity against a range of bacteria and fungi strains implicated in diarrhoea. Bioguided isolation of the active component(s) and evaluation of the mechanism of action is ongoing. doi:10.1016/j.sajb.2017.01.129 An up to date assessment of the conservation status of all South African species H. Mtshali, L. Von Staden, D. Raimondo Threatened Species Programme, South African National Biodiversity Institute, PO, Box 52099, Berea Road, Durban 4007, South Africa E-mail address: mtshalih@botanicalsociety.org.za (H. Mtshali)