The bulbs of the South African Drimia altissima (Asparagaceae or Hyacinthaceae sensu APGII) have yielded a range of previously undescribed bufadienolides, drimianins A-G ( 1 - 7 ), the known bufadienolides bovogenin A ( 8 ), 3β- O- β-d - glucopyranosylbovogenin A ( 9 ), scillaren F ( 10 ), and altoside ( 11 ), the known homoisoflavonoid (3 S ) - 3-(4'-methoxybenzyl)-5,6,7-trimethoxychroman-4-one (urgineanin C), the sesquiterpenoids 1β,6α-dihydroxy-4(15)-eudesmene and 6α-hydroxy-4(15)-eudesmen-1-one, polybotrin, adenosine, and 9 R -hydroxy-(10 E ,12 Z )-octadecadienoic acid ethyl ester. The bufadienolides isolated were tested at 10 μM in the NCI-60 cancer cell screen, and nine of these were selected for further screening at five concentrations. Drimianins C ( 3 ) and E ( 5 ) showed activity at the nanomolar level against a number of human cancer cell lines in the NCI-60 screen.

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Ethnopharmacological relevance Viral respiratory infections are amongst the most common infections globally, with most of the world's population contracting at least one infection annually. Numerous plant species are used in traditional southern African healing systems to treat these diseases and to alleviate the symptoms. Despite this, the therapeutic potential of these plants against viral respiratory diseases remains poorly explored. Aim of the study The aim of this study was to document the southern African plant species used in traditional medicine to treat viral respiratory infections. We also examined the extent of scientific evaluations of southern African plant species against the respiratory-infective viruses, with the aim of stimulating interest in this area and focusing on future studies. Materials and methods We undertook an extensive review of ethnobotanical books, reviews and primary scientific studies to identify southern African plants which are used in traditional southern African medicine to treat viral respiratory diseases. This information was used to identify gaps in the current research that require further study. Results Two hundred and fifty-seven southern African plant species were identified as traditional therapies for viral respiratory diseases. Surprisingly, only one of those species (as well as twenty-one other species not recorded for these purposes) has been evaluated for the ability to block respiratory virus production. Furthermore, most of these studies screened against a single viral strain and none of those studies examined the mechanism of action of the plant preparations. Conclusions Despite well documented records of the use of southern African plants to treat respiratory viral diseases, the field is poorly explored. Nearly all of the plant species used in traditional healing systems to treat these diseases are yet to be tested. Substantial further work is required to verify the efficacy of these traditional medicines.

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The inadequacy of information impedes society's competence to find out the cause or degree of a problem or even to avoid further losses in an ecosystem. It becomes even harder to identify all the biological resources at risk because there is no exhaustive inventory of either fauna or flora of a particular region. Coastal forests of Kenya are located in the southeast part of Kenya and are distributed mainly in four counties: Kwale, Kilifi, Lamu, and Tana River County. They are a stretch of fragmented forests ca. 30-120 km away from the Indian Ocean, and they have existed for millions of years. Diversity of both fauna and flora is very high in these relicts and the coastal forests of Eastern Africa, extending along the coast from Somalia through Kenya and Tanzania to Mozambique, are ranked among the priority biodiversity hotspot in the world. In spite of the high plant species richness and their importance towards supporting the livelihoods of the communities that live around them, floristic studies in these forests have remained poorly investigated. Hence, based on numerous field investigations, plant lists from published monograph/literature, and data from BRAHMS (Botanical Records and Herbarium Management System) database at East African herbarium (EA), we present a detailed checklist of vascular plants recorded in this region. Our results show that Kenyan coastal forests play an essential role in the flora of Kenya and the plant diversity of the coastal forests of East Africa. The checklist represents 176 families, 981 genera, 2489 species, 100 infraspecific taxa, 90 endemic plants species, 72 exotic species, and 120 species that are included in the current IUCN Red List of Threatened Species as species of major concern. We also discovered three new species to the world from these relicts. Thus, Kenyan coastal forests present a remarkable and significant center of plant diversity.

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Phylogenetic analysis aims to produce a bifurcating tree, which disregards conflicting signals and displays only those that are present in a large proportion of the data. However, any character (or tree) conflict in a dataset allows the exploration of support for various evolutionary hypotheses. Although data-display network approaches exist, biologists cannot easily and routinely use them to compute rooted phylogenetic networks on real datasets containing hundreds of taxa. Here, we constructed an original neighbour-net for a large dataset of Asparagales to highlight the aspects of the resulting network that will be important for interpreting phylogeny. The analyses were largely conducted with new data collected for the same loci as in previous studies, but from different species accessions and greater sampling in many cases than in published analyses. The network tree summarised the majority data pattern in the characters of plastid sequences before tree building, which largely confirmed the currently recognised phylogenetic relationships. Most conflicting signals are at the base of each group along the Asparagales backbone, which helps us to establish the expectancy and advance our understanding of some difficult taxa relationships and their phylogeny. The network method should play a greater role in phylogenetic analyses than it has in the past. To advance the understanding of evolutionary history of the largest order of monocots Asparagales, absolute diversification times were estimated for family-level clades using relaxed molecular clock analyses.

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Background Previous phylogenetics studies of Asparagales, although extensive and generally well supported, have left several sets of taxa unclearly placed and have not addressed all relationships within certain clades thoroughly (some clades were relatively sparsely sampled). One of the most important of these is sampling within and placement of Nolinoideae (Ruscaceae s.l.) of Asparagaceae sensu Angiosperm Phylogeny Group (APG) III, which subfamily includes taxa previously referred to Convallariaceae, Dracaenaaceae, Eriospermaceae, Nolinaceae and Ruscaceae. Methods A phylogenetic analysis of a combined data set for 126 taxa of Ruscaceae s.l. and related groups in Asparagales based on three nuclear and plastid DNA coding genes, 18S rDNA (1796 bp), rbcL (1338 bp) and matK (1668 bp), representing a total of approx. 4·8 kb is presented. Parsimony and Bayesian inference analyses were conducted to elucidate relationships of Ruscaceae s.l. and related groups, and parsimony bootstrap analysis was performed to assess support of clades. Key results The combination of the three genes results in the most highly resolved and strongly supported topology yet obtained for Asparagales including Ruscaceae s.l. Asparagales relationships are nearly congruent with previous combined gene analyses, which were reflected in the APG III classification. Parsimony and Bayesian analyses yield identical relationships except for some slight variation among the core asparagoid families, which nevertheless form a strongly supported group in both types of analyses. In core asparagoids, five major clades are identified: (1) Alliaceae s.l. (sensu APG III, Amarylidaceae-Agapanthaceae-Alliaceae); (2) Asparagaceae-Laxmanniaceae-Ruscaceae s.l.; (3) Themidaceae; (4) Hyacinthaceae; (5) Anemarrhenaceae-Behniaceae-Herreriaceae-Agavaceae (clades 2-5 collectively Asparagaceae s.l. sensu APG III). The position of Aphyllanthes is labile, but it is sister to Themidaceae in the combined maximum-parsimony tree and sister to Anemarrhenaceae in the Bayesian analysis. The highly supported clade of Xanthorrhoeaceae s.l. (sensu APG III, including Asphodelaceae and Hemerocallidaceae) is sister to the core asparagoids. Ruscaceae s.l. are a well-supported group. Asparagaceae s.s. are sister to Ruscaceae s.l., even though the clade of the two families is weakly supported; Laxmanniaceae are strongly supported as sister to Ruscaceae s.l. and Asparagaceae. Ruscaceae s.l. include six principal clades that often reflect previously named groups: (1) tribe Polygonateae (excluding Disporopsis); (2) tribe Ophiopogoneae; (3) tribe Convallarieae (excluding Theropogon); (4) Ruscaceae s.s. + Dracaenaceae + Theropogon + Disporopsis + Comospermum; (5) Nolinaceae, (6) Eriospermum. Conclusions The analyses here were largely conducted with new data collected for the same loci as in previous studies, but in this case from different species/DNA accessions and greater sampling in many cases than in previously published analyses; nonetheless, the results largely mirror those of previously conducted studies. This demonstrates the robustness of these results and answers questions often raised about reproducibility of DNA results, given the often sparse sampling of taxa in some studies, particularly the earliest ones. The results also provide a clear set of patterns on which to base a new classification of the subfamilies of Asparagaceae s.l., particularly Ruscaceae s.l. (= Nolinoideae of Asparagaceae s.l.), and examine other putatively important characters of Asparagales.

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