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1.
Baccharis dracunculifolia DC. and Baccharis microdonta DC. (Asteraceae) are woody species morphologically similar growing in Uruguay, where not taxonomists people often confuse them in field conditions. As the essential oil of B. dracunculifolia (‘vassoura’ oil) is highly prized by the flavor and fragrance industry, the correct differentiation of the two species is a key factor in exploiting them profitably and reasonably. To differentiate both Baccharis species, in this work their volatile expression profiles were studied as an alternative tool to determine authenticity and quality. Volatile organic compounds (VOCs) were monthly extracted during an entire year from aerial parts of wild populations by simultaneous distillation extraction (SDE), and studied by gas chromatography/mass spectrometry (GC/MS; identification) and conventional gas chromatography (GC-FID; component abundances determination). Enantioselective gas chromatography/mass spectrometry (Es-GC/MS) was applied in the search of parameters able to ensure genuineness of each species extract. Qualitative VOCs profiles were found to be similar for both species, being β-pinene, limonene, spathulenol, caryophyllene oxide, and viridiflorol the main components. However, the abundance of those VOCs were two to ten times higher in B. dracunculifolia than in B. microdonta during the year of study. These Baccharis spp. showed species-specific patterns of VOCs expression according to the seasonality, and interestingly, oxygenated compounds (trans-pinocarveol and myrtenal) increased their abundances at full-flowering stages. The enantiomeric distribution of selected monoterpenes (α- and β-pinenes, limonene, linalool, terpinen-4-ol, and α-terpineol) presented differential values for both Baccharis spp., meaning that Es-GC might be a useful tool for differentiating chemically both species in Uruguay for genuineness determination purposes.  相似文献   

2.
Chemical bioprospecting is an important tool for generating knowledge regarding local human‐threatened floras and for conservation management. For Baccharis L. (Asteraceae), several volatile components have been reported for Brazil, Argentina, Bolivia, and Chile as a result of bioprospection, but not for Uruguayan flora, which is composed of more than 50 native species. In this work, through collection of aerial parts of different species and volatile simultaneous‐distillation extraction and gas chromatography‐mass spectrometry analyses, twelve native species of Baccharis were studied (B. articulata, B. cultrata, B. genistifolia, B. gibertii, B. gnaphalioides, B. ochracea, B. phyteumoides, B. punctulata, B. crispa, B. dracunculifolia, B. linearifolia subsp. linearifolia, and B. spicata). A detailed analysis of the male and female volatile composition was conducted for the last four species. The profiles of B. cultrata, B. genistifolia, B. gibertii, and B. gnaphalioides are reported for the first time. Because half of the species analyzed in this work are in Uruguay and are threatened or potentially threatened by human economic activities, the importance of their conservation as natural, sustainable resources is highlighted.  相似文献   

3.
Baccharis is a widespread genus belonging to the Asteraceae family that includes almost 400 species exclusively from the Americas. Even when studied in detail, the taxonomic classification among species from this genus is not yet fully defined. Within the framework of our study of the volatile composition of the Baccharis genus, four species (B. trimera, B. milleflora, B. tridentata, and B. uncinella) were collected from the ‘Campos de Cima da Serra’ highlands of the Brazilian state of Rio Grande do Sul. The aerial parts were dried and extracted by the simultaneous distillation extraction (SDE) procedure. This is the first time that SDE has been applied to obtain and compare the volatile‐extract composition in the Baccharis genus. Characterization of the volatile extracts allowed the identification of 180 peaks with many coeluting components; these latter being detailed for the first time for this genus. The multivariate statistical analyses allowed separating the volatile extracts of the four populations of Baccharis into two separate groups. The first one included the B. milleflora, B. trimera, and B. uncinella volatile extracts. The three species showed a high degree of similarity in their volatile composition, which was characterized by the presence of high contents of sesquiterpene compounds, in particular of spathulenol. The second group comprised the extract of B. tridentata, which contained α‐pinene, β‐pinene, limonene, and (E)‐β‐ocimene in high amounts.  相似文献   

4.
Baccharis spicata, a species native to South America (southern Brazil, Paraguay, Uruguay, and northeastern and central Argentina) is reported for the first time from Europe. In September 2015, two naturalized populations were detected in the surroundings of Porto (Matosinhos and Vila do Conde) in Portugal. Based on literature data, the species’ taxonomy and nomenclature are analyzed and it is described and illustrated. Furthermore, its ecology, habitat, biology, and possible vector of introduction are discussed. Finally, its invasive potential for the European Union is assessed, based on climatic variables and two different risk assessment methods.  相似文献   

5.
Baccharis plants have been used since ancient times in American traditional medicine. Baccharis chilco is a perennial shrub of temperate regions of South America that grows well in rainfall forests of Colombia. Neither chemical composition nor biological studies of this plant have ever been reported. Two caffeoylquinic acid (CQA) derivatives, 5‐O‐[(E)‐caffeoyl]quinic acid ( 1 ) and 3,5‐di‐O‐[(E)‐caffeoyl]quinic acid ( 3 ), and rosmarinic acid ( 2 ) have been isolated from B. chilco growing wild in Colombia, using the on‐line HPLC‐DAD‐DPPH radical‐scavenging detection technique as guidance. In the course of the purification work, L ‐chiro‐inositol ( 4 ) was also isolated. Structures of the four isolated compounds were determined by spectroscopic methods. Antioxidants 2 and 3 exhibited high antiradical activities evaluated by the 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH.) assay, although somewhat lower than that of the reference compound ascorbic acid. The on‐line HPLC‐DAD‐DPPH technique allowed a rapid pinpointing of antioxidants in the studied EtOH extract, and the facile guided isolation of the target molecules.  相似文献   

6.
Climate has an important influence on the distribution and abundance of invasive species. Habitat suitability for invasive plants could shift with a changing climate and management practices may need to shift in response. Anecdotal evidence suggests that groundsel bush (Baccharis halimifolia) has declined in abundance over the past 50 years in Australia, co-incident with the introduction of a suite of biological control agents. While biological control may be responsible for this decline, here we investigate an alternative hypothesis—that long-term change in the favourability of the climate may have changed growth conditions for groundsel bush throughout its Australian range. We also predict what may happen to the future distribution of this species, using a bioclimatic modelling technique (CLIMEX). We found a significant reduction in the favourability for growth of B. halimifolia over the past 50 years at 29 sites in Australia. Under a likely IPCC future climate scenario prediction (decrease in rainfall and increase in temperature), the favourability for growth of B. halimifolia will continue to decrease in Queensland and its distribution may move further south into New South Wales and Victoria. We conclude that climate alone may have had a significant effect on the distribution and abundance of B. halimifolia and future priorities for management of B. halimifolia should focus on its southern distribution. Determining the success of the biological control programme in isolation from the observed climate effects will be difficult. Given the likelihood of future climate change worldwide evaluation of biological control programmes in general will need to also account for climate effects.  相似文献   

7.
A new species of Baccharis L. sect. Caulopterae DC. (Compositae) of the high altitude grasslands of Southern Brazil is presented: Baccharis sphagnophila A. A. Schneid. & G. Heiden. The new species is described, illustrated and compared with similar species.  相似文献   

8.
The chemical composition and seasonal variation throughout one year of the essential oils from leaves of Baccharis microdonta and B. elaeagnoides, collected in Campos do Jordão, SP, were investigated. The composition of the latter species has been described for the first time. By GC (RI) and GC/MS analysis, 43 compounds were identified, and a predominance of oxygenated sesquiterpene derivatives was found in both species. The main components of the B. microdonta oils were elemol ( 31 ; 11.7–30.6%), spathulenol ( 34 ; 4.7–9.1%), β‐caryophyllene ( 19 ; 3.7–6.2%), and germacrene D ( 24 ; 2.9–12.2%), and those of the B. elaeagnoides oils were 34 (10.1–21.5%), viridiflorol ( 35 ; 3.6–18.4%), 24 (0.9–13.8%), and 19 (3.5–9.4%). The identified compounds were grouped according to their respective C‐skeletons, and the percentages of occurrence of the C‐skeletons in the essential oils of leaves collected in the four seasons allowed identifying the preferential accumulation of different types of C‐skeletons as well as the seasonal variation of the biosynthetic routes over the studied period.  相似文献   

9.
10.
Several Baccharis species are popularly known in traditional medicine as “carquejas”, “vassouras”, “ervas-santas” and “mio-mios”, and are used as anti-inflammatories, digestives, and diuretics. This study aimed to investigate the chemical compositions and cytotoxic activities of essential oils (EOs) of six Baccharis species belonging to subgenus Coridifoliae, namely B. albilanosa, B. coridifolia, B. erigeroides, B. napaea, B. ochracea, and B. pluricapitulata. GC/MS analyses of the EOs showed that the oxygenated sesquiterpenes spathulenol (7.32–38.22 %) and caryophyllene oxide (10.83–16.75 %) were the major components for all the species. The EOs of almost all species were cytotoxic against cancer (BT-549, KB, SK-MEL and SK-OV-3) and normal kidney (VERO and LLC-PK1) cell lines, whereas B. erigeroides EO showed cytotoxicity only against LLC-PK1. This article augments the current knowledge about the chemical-biological properties of Baccharis subgenus Coridifoliae and discusses the therapeutic potentials of these economically unexploited plants.  相似文献   

11.
The investigation of ten Baccharis species afforded in addition to known compounds eight new diterpenes, four ent-labdanes, three kaurenes and a clerodane derivative. Furthermore, two new p-hydroxyacetophenones, a flavone, 3′-methoxyxanthomicrol and two matricaria ester derivatives were isolated. The structures were elucidated by spectroscopic methods and a few chemical transformations. The chemotaxonomic situation of the large genus is discussed briefly.  相似文献   

12.
13.
The ability of two plant-produced macrocyclic trichothecenes (baccharinoid B4 and roridin E) to induce callus growth of two trichothecene-producing Baccharis species (B. coridifolia and B. megapotamica) and two nontrichothecene-producing species (B. halimifolia and B. neglecta) was investigated. Roridin E had no effect in the induction of callus of B. coridifolia, a roridin-producing plant, but induced callus of nonroridin-producing plants (B. megapotamica, B. halimifolia, and B. neglecta). Baccharinoid B4 stimulated callus growth of B. megapotamica, a baccharinoid-producing plant, and inhibited growth of B. coridifolia, B. halimifolia, and B. neglecta callus tissues. The ability of roridin E to induce callus was most effective at concentrations of 10–8 and 10–6 M and when synergistically coupled with auxin, 2,4-dichlorophenoxyacetic acid (2,4-D). The ability of baccharinoid B4 to stimulate callus growth appeared to increase with increased concentration in the culture medium. Analysis of callus cultures grown in medium amended with roridin E showed that B4, roridin E, and 8-hydroxyroridin E and verrucarols were formed in the tissues but not in the medium. The results of this study indicated that while the callus-inducing ability of roridin E seemed to be nonspecies-specific in nature, the ability of B4 to stimulate callus was a highly species-specific phenomena. Callus-inducing activity of roridin E may depend on the capacity of plant species to transform exogenous roridin E into baccharinoids or other macrocyclic trichothecene derivatives.  相似文献   

14.
Species diagnosis is of the utmost importance to both pest management and plant quarantine services. Because of difficulties in the morphological diagnosis of spider mites, molecular techniques are of great value to rapidly and accurately diagnose closely related species. We examined four species of genus Tetranychus (the green and red forms of T. urticae, and T. kanzawai, T. phaselus and T. truncatus), which are found in Korea and are of significance to plant quarantine services. DNA samples isolated from a single egg, larva or adult weighed 64–188 ng. We designed species‐specific primers by performing sequence alignment for 107 sequences of the ribosomal internal transcribed spacer 2 (ITS2) region, which we obtained from GenBank, and sequences generated in this study. Specific nucleotides of each species were selected for designing primers specific for each species. Each species‐specific primer pair, when used to perform PCR analyses, detected only the species from which it originated. However, a T. urticae‐specific primer pair did not discriminate between the green and red forms of this species. These species‐specific primers can be applied in practice for the rapid and accurate diagnosis of spider mite species in plant quarantine and in agricultural fields.  相似文献   

15.
Emine Aslan  Dogan Arslan 《Phyton》2020,89(4):1091-1099
The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium Turra. and Hypericum scabrum L. species which are naturally distributed in the flora of Siirt province, Turkey. Hypericin contents of Hypericum species grown in different geographical aspects (North, South, East, and West), and it was measured at different harvest times (full blooming and post blooming period). In the current study, it has been determined that total hypericin content varies considerably according to aspects, plant developmental stages (ontogenetic variance), and species. According to species x aspect interaction, the highest total hypericin content was recorded from the west aspect (3.13 mg/g) in Hypericum triquetrifolium, while, the lowest hypericin content was also obtained from the west aspect (1.22 mg/g) in Hypericum scabrum. When the highest total hypericin content was analyzed according to aspect x species x harvest time interaction, the highest total hypericin content was produced from Hypericum triquetrifolium at the harvest of west aspect with 5.28 mg/g, while the minimum amount of hypericin was obtained from the same aspect in Hypericum scabrum with 0.50 mg/g. In species x harvest time interaction, the highest total hypericin content was obtained from the full bloom (3.10 mg/g) harvest in Hypericum triquetrifolium, while the lowest hypericin was obtained from the full bloom (1.26 mg/g) harvest in Hypericum scabrum. The data suggest that the average total hypericin content was 2.26 mg/g in Hypericum triquetrifolium and 1.28 mg/g in Hypericum scabrum.  相似文献   

16.
A new yeast species, Kazachstania wufongensis, is proposed in this paper based on six strains isolated from soil in Taiwan. The species may produce one to four ellipsoidal ascospores in each ascus, directly transformed from diploid cells. Genus assignment and distinction of the species from other recognized species of Kazachstania is based on morphological and physiological characteristics, and on phylogenetic analysis of nucleotide sequences of the D1/D2 domains of the large subunit (LSU) rRNA gene. Sequence analysis of the D1/D2 domains of the LSU rRNA gene reveals that K. wufongensis is a member of the Kazachstania exigua complex, and its phylogenetically closest relatives are K. exigua, K. barnettii, K. bulderi, and K. turicensis. The species can be further differentiated from the other phylogenetically related species based on internal transcribed spacer sequence and electrophoretic karyotype. Therefore, the new species Kazachstania wufongensis sp. nov. is proposed. The type strain of this new species, which was isolated from forest soil in Wufong, Hsinchu, Taiwan, is FN21S03T (=CBS 10886T = BCRC 23138T).  相似文献   

17.
18.
Desmos caudatus C. E. C. Fisch. (Annonaceae), a species of small tree known only from a couple of collections from the south of Burma, is transferred to Meiogyne. This is the first record of the genus from Burma.  相似文献   

19.
20.
Two species of nematodes, Angiostoma coloaense n. sp. and Aulacnema monodelphis n. g., n. sp. (Angiostomatidae: Rhabditida) are described from terrestrial molluscs of Vietnam. Both species are characterised by a long bowl-shaped buccal cavity and typically angiostomatid male bursal alae, spicules and gubernaculum. The new genus, Aulacnema n. g., is erected for the first reported monodelphic angiostomatid. Angiostoma coloaense n. sp. can be distinguished from other species of Angiostoma Dujardin, 1845 by having a buccal cavity length greater than its width and the absence of tail spikes on both males and females.  相似文献   

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