Sampling within the Conophytum-clade was therefore greatly expanded and phylogenetic sequence data from ten plastid gene regions and the nuclear ITS region were generated and analysed. Three main subclades were recovered in the phylogenetic analyses, the one comprising woody shrubs or shrublets and the other two highly reduced shrublets. The phylogenetic position of the as yet unplaced multilocular genus Arenifera was also clariﬁed and together with Octopoma and Cheiridopsis is shown to be non-monophyletic. As such generic circumscriptions are assessed and revised using morphological and phylogenetic data. doi:10.1016/j.sajb.2015.03.109
Effects of seed ﬂavonoid and anthocyanin content on the symbiotic performance of Bradyrhizobium-inoculated Bambara groundnut (Vigna subterranea L.) landraces D.K. Puozaaa, B.D.K. Ahiaborb, F.D. Dakorac a Department of Crop Sciences, Tshwane University of Technology, Private Bag X680, Pretoria 0001, South Africa b CSIR-Savanna Agricultural Research Institute, Ghana c Chemistry Department, Tshwane University of Technology, Private Bag X680, Pretoria 0001, South Africa The legume-Rhizobium symbiosis is initiated by the release of seed and root exudates in the form of ﬂavonoids and anthocyanins which act as chemical signals to compatible soil bacteria in the rhizosphere. The seed of different legume genotypes has been demonstrated to contain varying amounts of these phenolic compounds. Bambara groundnut is the third most important food legume in most of sub-Saharan Africa and is widely included in cropping systems due to its ability to ﬁx N2 and provide a cheaper source of dietary protein. A study was conducted with the objectives to determine ﬂavonoid and anthocyanin concentrations, estimate N-ﬁxing capacity and assess response to Bradyrhizobium inoculation of Bambara groundnut landraces with different seed coat colours. Seed extracts of four landraces identiﬁed by their seed coat colours as Blackeye, Black-mottled, Red-mottled and Cream were assayed to quantify ﬂavonoid and anthocyanin contents using spectrometry. Field experiments were set up at four locations in Ghana and South Africa. N2 ﬁxation was determined using 15N isotopic method by mass spectrometry. Results revealed signiﬁcant differences among the genotypes for both ﬂavonoid and anthocyanin levels. Black-mottled had greater concentrations of these phenolic compounds. Cream recorded the least anthocyanin content but its ﬂavonoid concentration was higher than that of Red-mottled. The concentrations of these compounds were affected by the time of storage of the seed but not the environment under which the crop was harvested. Nodulation, δ15N, %Ndfa, N-ﬁxed (kg.ha- 1) and soil N uptake varied among the landraces in both countries. In Ghana, Blackmottled showed the least δ15N value of +0.51‰ while in South Africa Red-mottled recorded the least value (+3.22‰). Hence these genotypes ﬁxed greater amounts of N compared to the other landraces. Blackmottled was also superior in grain production. The response of the test genotypes to Bradyrhizobium inoculation was highly dependent on environment.
Cancer is considered to be one of the major causes of death worldwide. Cancer occurrence and cancer related death numbers seem to be increasing in Africa, Asia and Central and South America. Currently, more than 100 000 cases are reported each year in South Africa. Skin cancer is considered the most prevalent cancer in South Africa. The current study focused on four indigenous South African plants and the potential of their ethanolic extracts of different plant parts for anticancer activity against squamous cell (A431) carcinoma. The plants were investigated for their cytotoxicity on a human skin cancer cell line and a non-cancerous cell line using the sodium 3′-[1(phenyl amino carbonyl)3,4-tetrazolium]-bis-[4-methoxy-6-nitrobenzene] sulfonic acid hydrate (XTT) Cell Proliferation Kit II. The extract's antioxidant activity was determined by measuring the extract's ability to scavenge 2, 2-diphenyl1-picrylhydrazyl radical (DPPH); nitric oxide (NO) radical and the superoxide (O−2) radical. The mechanism of action of the extracts was determined using confocal microscopy. The ethanolic fruit extract of CM (Combretaceae) showed the highest cytotoxic activity on the A431 cells with an IC50 of 26.9 μg/ml, whereas the IC50 values of the other extracts (Euclea crispa, Sideroxylon inerme and Terminalia prunioides) ranged from 41.8 μg/ml to 158.6 μg/ml. The CM fruit extract also showed high inhibition of the DPPH free radical (5.1 μg/ml) but not for the nitric oxide free radical (180.3 μg/ml) or the superoxide radical (166.7 μg/ml). Furthermore, the A431 cells showed signs of apoptotic cell death after exposure with various concentrations (12.5 μg/ml to 50 μg/ml) of the CM fruit extract. CM showed signiﬁcant activity against A431 cells and high radical scavenging activity against the DPPH free radical. From the confocal microscopy images morphological characteristics of apoptosis were observed. doi:10.1016/j.sajb.2015.03.111
Ethonobotanical inventory of tree species within home-gardens of Tshamutilikwa village in Thulamela Municipality, Limpopo Province, South Africa M. Ramashamba, M.P. Tshisikhawe Department of Botany, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa The study documents and identiﬁes tree species which are found within home-gardens (ngade), tree species recorded were classiﬁed into families, also the utilization option and plant parts used around Thulamela local municipality. This study was carried out within forty ﬁve home-gardens in Tshamutilikwa village of Thulamela local municipality. Thirty tree species were documented and categorized according to their uses and plant parts which are being used. The most dominant family was Fabaceae (n = 5) followed by Anacardiceae (n = 2) and Combretaceae (n = 2). Most of the tree species found were used by local people to support their daily nutritional uptake (e.g. Mangifera indica and Persea americana). Home-gardens serve as ex-situ conservation because they conserve gene and protect some of the endangered species. Species found within the home-gardens are used for food (41%), medicines (49%), ﬁrewood (8%) and beverages (2%). Plant part utilization is mainly in the form of fruits (33%), leaves (20%), roots (15%), stem barks (15%) and whole plant (15%).
doi:10.1016/j.sajb.2015.03.110 doi:10.1016/j.sajb.2015.03.112 Anticancer activity and mechanism of action of plant extracts on squamous cell carcinoma S. Rademan, D. Berrington, D. Bodiba, N. Lall Department of Plant Sciences, University of Pretoria, Pretoria 0002, South Africa
Investigating the potential of a traditional medicinal plant as an adjuvant remedy in the treatment of breast cancer A. Rautenbacha,⁎, T. Goldswainb, T. Davisb, A. Krygsmanb, A.-M. Engelbrechtb, N.P. Makungaa