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The chemotaxonomy, Phylogeny and Biological activity of the genus Eriocephalus L. (Asteraceae) species
Abstract
the research was based chemotaxonomy, phylogeny and biological activity of 22 species of the genus Eriocephalus found in southern Africa
... Industrially, the oils from .E. punctulatus ("Cape chamomile") and .E. africanus ("Cape snowbush") have a wide application in perfumes, skin care preparations and as blend oils in beauty care products. The aromatherapeutic properties of the former oil include being an analgesic, anti-allergic, antidepressant, antiseptic, and anti-inflammatory and as a diuretic among its numerous applications ( Mierendorff et al., 2003;Njenga, 2005). ...
... Despite the extensive traditional and commercial use of this indigenous genus, scientific data confirming its biological activity is lacking. On the other hand, the presence of various classes of flavonoids noted in species of this genus ( Zdero et al., 1987;Wollenweber and Mann, 1989;Bohm and Stuessy, 2001;Njenga, 2005), necessitate further analysis for the presence of new biologically active constituents such as anti-oxidants. Flavonoids are known to have a broad spectrum of biochemical activities including effects on immune and inflammatory responses and thus it is important to screen the species of the genus under study to document phyto-and ethnomedical properties. ...
... Flavonoids are among the naturally occurring plant secondary metabolites that have been reported to have broad pharmacological activity including strong anti-oxidant, diuretic and diaphoretic properties. The anti-oxidant activity noted in most of the species could be attributed to the presence of flavones and flavanones that were abundant in the leaf extracts (Njenga, 2005). Further study should be conducted to evaluate their toxicity profiles and safety indices. ...
The genus Eriocephalus (Asteraceae) is endemic to South Africa where some of the species are used traditionally to treat dermal infections, gastro-intestinal disorders, and upper respiratory tract infections. In vitro screening for the presence of anti-oxidants was carried out on acetone leaf extracts of 22 species (80 samples) collected from wild populations using the 2,2, diphenyl-1-picryhydrazyl (DPPH) radical scavenging method. The extracts showed moderate activity with the IC50 values ranging between 21.5 μg ml−1 (E. punctulatus) and 79 μg ml−1. The hydrodistilled essential oils were also tested but did not show activity at the starting concentration of 100 μg ml−1. Essential oils of seventeen species were screened for the presence of inhibitors of 5-lipoxygenase enzyme. The IC50 values ranged between 19 μg ml−1 (E. africanus) and 98.9 μg ml−1. Variation between and within natural populations with respect to the activities tested is also documented.
... africanus and E. africanus var. paniculatum were recommended in traditional medicine for the treatment of oedema, disorders and dermal infections (Njenga 2005). The species E. punctulatus combined with Metalasia muricata has been explored by local African tribes, such as southern Sotho, to fumigate the hut of persons suffering from a cold or to perfume bodies after death (Njenga 2005). ...
... paniculatum were recommended in traditional medicine for the treatment of oedema, disorders and dermal infections (Njenga 2005). The species E. punctulatus combined with Metalasia muricata has been explored by local African tribes, such as southern Sotho, to fumigate the hut of persons suffering from a cold or to perfume bodies after death (Njenga 2005). ...
Essential oil (EO) from Eriocephalus africanus L. leaves was evaluated against the growth of some phytopathogenic bacteria including Agrobacerium tumifaciens, Dickeya solani, Erwinia amylovora, Pseudomonas cichorii and Serratia pulmithica using the disc diffusion method and minimum inhibitory concentration (MIC) evaluation. Ten compounds in the EO with dominance of Artemisia ketone (2,5,5-trimethyl-2,6-heptadien-4-one) (77.92%) and ledol (19.92%) were revealed. The antibacterial activity indicated efficacy of essential oil against majority of strains isolated. The most effective action was recorded against D. solani, by 7.5 and 10 µL of oil, with 18.33 mm and 100 μg/mL as zone inhibition and MIC, respectively, whereas the lowest activity was exhibited against P. cichorii (diameter inhibition = 6.66 mm at 10 µL of oil, MIC = 100 μg/mL). The strain S. pulmithica appears to be resistant to the oil when the activity is measured by 10 µL of oil but its growth inhibition was reported with a MIC of 100 μg/mL.
... In this system, many species of birds use seed material from plants in the genus Eriocephalus to construct their nests [17]. Eriocephalus plants are highly aromatic [18] and produce many small seed heads that are surrounded by white, cotton-like fluff (figure 1). Birds that incorporate Eriocephalus seed material into their nests may benefit in diverse ways. ...
... Eriocephalus (Asteraceae; wild rosemary) are highly aromatic, perennial shrubs native to southern Africa [18]. In the most recent taxonomic treatment of this group, Müller et al. [33] recognized 32 species within the genus Eriocephalus based on morphology. ...
Characterizing many species interactions as mutualisms can be misleading because some members of the interaction derive greater fitness benefits at the expense of other members. We provide detailed natural history data on a suspected bird-plant mutualism in South Africa where many species of birds use fluffy Eriocephalus seed material to construct their nests, potentially dispersing seeds for the plant. We focus on a common bird, Prinia maculosa, which invests heavily in gathering Eriocephalus material. Prinias spent 5 of their median 6-day nest construction period adding seed material to their nests and frequently travelled outside their territory boundary to gather Eriocephalus material. Yet, prinias gathered primarily Eriocephalus fluff and actively avoided gathering seeds. The average prinia nest contained only 6.6 seeds, but contained fluff from 579 seeds. These data suggest that prinias provide limited dispersal benefits to Eriocephalus plants. By contrast, the large amounts of Eriocephalus fluff in prinia nests, and the effort that prinias invest in gathering it, suggest that prinias benefit from constructing their nests with Eriocephalus material. We end by outlining hypotheses for possible fitness benefits that Eriocephalus material could provide prinias and other birds.
... Also, an aqueous extract of E. africanus has been proved to significantly attenuate nociception and pyrexia in in vivo mice models, thus confirming its analgesic and antipyretic properties (Amabeoku et al., 2000). Moreover, antipyretic, analgesic, anti-allergic, antidepressant, antiseptic, anti-inflammatory and antioxidant properties were reported for acetone extracts and essential oils of E. africanus leaves (Njenga, 2005). ...
... As indicated in Table 4, the IC 50 estimated for the stems extracts was 17 ± 1 lg/mL, 57 ± 4 lg/mL and 418 ± 27 lg/mL for DPPH Å scavenging, reducing power and lipid peroxidation assays respectively, while that of the leaves extracts was 28 ± 4 lg/mL, 96 ± 8 lg/mL and 333 ± 18 lg/mL, respectively. Interestingly, the IC 50 herein estimated for DPPH Å scavenging was lower than that previously described for acetone extracts from leaves, which ranged from 38 to 50 lg/mL (Njenga, 2005). This could be due to various aspects including different preparative procedures of the plant extracts, timing of collection of the plant material, geographical origin and variability between plants, soil composition and others not considered. ...
Eriocephalus africanus, an Asteraceae plant endemic from South Africa and naturalized in the Mediterranean region, is commonly used in culinary and in traditional medicine. Despite the claimed health benefits attributed to this plant by the folk medicine, there is still a lack of scientific data to support this information.
The present study describes the main phenolic composition of hydroethanolic extracts from stems and leaves of E. africanus, along with the assessment of their antioxidant properties. The identification of the phenolic constituents on the stems and leaves from E. africanus was carried out by LC-DAD-ESI/MSn, and the structures of the two major HPLC-eluted compounds were further confirmed by NMR analysis.
Both extracts were rich in mono- and di-caffeoylquinic acids, which accounted for approximately 90% and 74% of total quantified phenolics, for the stems and leaves extracts, respectively. Besides, eriodictyol-hexuronide was found in considerable amounts in the extract from the leaves. One must highlight that these compounds together with other minor phenolic acids (namely other caffeoyl, ferulic and protocatechuic acid derivatives) and flavonoids (including hesperetin and eriodictyol) were herein identified for the first time.
Furthermore, through three in vitro methods, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH·) radical scavenging, ferric reducing antioxidant power and lipid peroxidation inhibition capacity assays, the antioxidant capacity of the extracts was measured, revealing promising properties.
Overall, these results are an important contribution for the elucidation of the phenolic composition of E. africanus, as well as for the understanding of the biological properties of this medicinal plant species.
... Prominent representatives of the Asteraceae in this order, amongst others Eriocephalus spp., Stoebe plumosa and Euryops walterorum, also have close relatives in the grasslands and adjacent Karoo vegetation in South Africa (cf. Nordenstam 1966;Müller et al. 2001;Njenga 2005), indicating a biogeographic relationship to these biomes, rather than the surrounding savanna biome. ...
Background: The Great Escarpment of southern Africa takes the form of an extended mountainous highland in central-western Namibia, commonly referred to as the ‘Khomas Hochland’. It is regarded as an area of high botanical diversity. Yet only few localised studies on the vegetation composition are available. The Khomas Hochland is formed on the southern part of the Damara Orogen and dominated by metamorphosed sediments. Climatically it forms a transition between the hot desert of the Namib and the slightly cooler hot steppe in the inland.Objectives: To classify and provide syntaxonomical descriptions of the vegetation of the Khomas Hochland.Methods: A dataset comprising 1151 relevés and 914 species was compiled from various surveys, mostly collected under, and to the standards of, the umbrella project ‘Vegetation Survey of Namibia’. For first classifications, the data set was reduced to a synusial set consisting of trees, shrubs, dwarf shrubs and grasses only.Results: The classification resulted in four major landscape units, being the Pre-Namib and Escarpment zone, the Khomas Hochland proper, riverine habitats as well as surrounding lowlands. The classification was further refined using Cocktail procedures to produce 30 associations, one with four sub-associations. These are described in this paper.Conclusion: A classification of synoptic data grouped the associations into five orders and one undefined cluster of associations on specialised desert habitats. Four of these orders correspond to the habitat types identified in the first classification. The fifth order, the Senegalio hereroensis–Tarchonanthoetalia camphorathi, represents high mountains of the central Khomas Hochland, which link biogeographically to the grassland biome in South Africa.
... It requires simple and fast methods to achieve a first path to explore the chemodiversity of wild populations. In that respect, as reported by Pothier et al., (2001) ;Taylor, (2001) ;Njenga, (2005) ;Chapman, (2009) and Franz, (2010); thin layer chromatography (TLC) can be considered as a useful methodology because of its simplicity, speed, reliability, economy and possibility of using in field conditions. Many recent reviews enhanced the increasing interest of thyme cultivation due to its wide range of applications derived from its biological activity and sensory characteristics: it is used in medical and pharmacological applications (Sáez, F. & Stahl-Biskup, 2002;Reddy et al., 2014;Hosseinzadeh, 2015;Miraj & Kiani, 2016;Kuete, 2017), and in food preservation (Embuscado, 2015), for example. ...
Chemodiversity of wild populations of aromatic plants is a valuable source of essential oils, whose composition may be suitable for specific purposes according their biological activity. Furthermore, knowing the intrapopulational variability based on individual analysis has allowed characterizing atypical profiles, which can reach high levels of active compounds. Obviously, it requires the treatment of a high number of individual samples. In this work, a methodology to characterize T. vulgaris profiles in an area of recognized biodiversity was proposed and applied. After Thin Layer Chromatography (TLC) screening data of 85 individual samples, 7 groups, and 13 individuals were classified. Then, 20 samples were subjected to GC/MS and GC/FID analysis, respectively. These data were subjected to Hierarchical Agglomerative, Discriminant Analysis and ANOVA, which finally highlighted five profiles: (1) based on the camphane skeleton (camphene, camphor and borneol), (2) rich in the oxygenated sesquiterpenic fraction, (3) rich in 1,8-cineole, with appreciable amounts of camphor and borneol (typical chemotype from Eastern Iberian Peninsula), (4) camphor and terpinen-4-ol as major compounds, and (5) linalool chemotype. It should be noted that the percentages of the main compounds in these groups were higher than some of those described in the literature for similar chemotypes. In summary, the preliminary screening by TLC, grouping individuals with similar profiles, allowed establishing a quick first approximation to the chemodiversity of T. vulgaris in the studied area. Furthermore, the analysis of unclassified and potentially atypical individuals has also provided valuable information to establish the final profiles.
The distinct blue essential oil obtained from Eriocephalus sp. (Asteraceae) is known in commerce as Cape chamomile and has become an important ingredient in flavour and fragrance formulations. To date, it is commonly accepted that Cape chamomile oil is obtained from Eriocephalus punctulatus. Samples of E. tenuifolius DC (n = 35) and E. punctulatus DC (n = 17) were collected from different localities in South Africa and Lesotho. The hydrodistilled essential oil was analysed by gas chromatography coupled to mass selective detector and flame ionisation detector (GC–MS-FID). The GC–MS data was exported to MetAlign™ for spectral alignment and differentiation. The mid-infrared red (MIR) spectral data was processed using principal component analysis (PCA), partial least squares (PLS) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) algorithms. The oil from E. punctulatus showed a different profile from the commercial sample which mostly contained 1,8-cineole, piperitone, yomogi alcohol and pogostol. MetAlign™ successfully discriminated between the oil obtained from the two species and this data together with multivariate analysis showed that the commercial oil was similar to E. tenuifolius oil. Using the MIR data, a three component OPLS-DA model was constructed which convincingly discriminated between E. tenuifolius and E. punctulatus oil. The developed model further predicted the botanical origin of the commercial oils to be E. tenuifolius. The statistical performance of the model was excellent with an R2X (cum) = 0.897; R2Y (cum) = 0.991 and Q2Y (cum) = 0.987.
Essential oils from the aerial parts of three Eriocephalus africanus L. var. africanus populations were analysed by means of GC–FID and GC–MS. Sixty-one constituents were identified, representing more than 96% of the total oil composition. Artemisia ketone (56.46–56.58%), intermedeol (9.19–11.63%) and γ-eudesmol (4.26–5.64%) were the main compounds. Application of the Pearson correlation coefficient showed high similarity between the nine samples analysed. Copyright © 2007 John Wiley & Sons, Ltd.
The investigation of nine Eriocephalus species afforded in addition to known compounds 40 new ones: 10 guaianolides, eight eudesmanolides, a germacranolide, a sesquiterpene lactone with new carbon skeleton, 18 derivatives of costic acid, a seco-eudesmane diketone and a chrysanthemol derivative. The structures were elucidated by high field NMR spectroscopy and a few chemical transformations. The chemotaxonomy of the genus is discussed briefly.