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1.
The only available ethnobotanical information on Pteronia incana has been recorded by the Montagu Museum in the Western Cape Province of South Africa. It was reported that the plant is used to treat influenza, fever, kidney ailments and backache. In common with other species of Pteronia, the plant contains an essential oil reminiscent of pine turpentine oil with β-pinene, limonene, 1,8-cineole, myrcene, spathulenol, p-cymene and methyleugenol as main compounds present in all or most of the samples, with smaller amounts of α-pinene, sabinene, γ-terpinene, terpinen-4-ol, biclogermacrene, globulol and α-bisabolol in some of the distillates. We investigated the oil composition of 11 individual plants collected at three geographically distant localities but found limited variation, both within and between populations. Leaf sections of P. incana showed that it is anatomically similar to P. divaricata in the presence of a secretory duct associated with the main vascular bundle (and often other bundles as well), in addition to glandular and non-glandular trichomes on both leaf surfaces. One yeast (Cryptococcus neoformans), two Gram-negative bacteria (Moraxella catarrhalis and Klebsiella pneumoniae) and one Gram-positive bacterium (Mycobacterium smegmatis) were selected for antimicrobial activity studies using the minimum inhibitory concentration (MIC) microtitre plate method. The results showed that methanol:dichloromethane (MeOH:CH2Cl2) extracts were active against M. smegmatis (lowest MIC values of 0.5–0.8 mg/ml) and C. neoformans (lowest MIC values of 0.5–2.0 mg/ml). The essential oil was most active against C. neoformans (lowest MIC value of 0.3 mg/ml). These results provide a scientific rationale for the use of P. incana in Cape herbal medicine.  相似文献   

2.
The essential oils of the aerial parts of nine species of Hypericum (Hypericum barbatum, Hypericum hirsutum, Hypericum linarioides, Hypericum maculatum, Hypericum olympicum, Hypericum perforatum, Hypericum richeri, Hypericum rumeliacum and Hypericum tetrapterum), collected from different locations in Southeast Serbia, were obtained by steam distillation and analyzed by GC and GC–MS. The essential oils investigated were characterized by a high content of non-terpene compounds and a low content of monoterpenes. The contents of non-terpenes, monoterpenes and sesquiterpenes in oils of the species H. barbatum, H. richeri and H. rumeliacum (section Drosocaprium) were similar and these oils were characterized by high contents of fatty acids. The oils of H. hirsutum and H. linarioides (section Taeniocarpium) contained a high percentage of n-nonane. There were similarities in contents of non-terpenes and sesquiterpenes in oils of species that belong to the section Hypericum (H. maculatum, H. perforatum and H. tetrapterum). The oil of H. olympicum differed from others by higher terpene content. A comparison was also carried out of the chemical composition of the essential oils from flower, leaf and stem of H. perforatum and it revealed that the highest concentration of non-terpene compounds was found in the flower and stem oil, while a high concentration of sesquiterpenes was characteristic for leaf oil. There were significant differences in the concentrations of the same compounds in the essential oils of H. maculatum, H. olympicum and H. perforatum, collected in different years from the same location which could be explained by seasonal differences. All data were statistically processed with principal component analysis and cluster analysis. The main conclusion from the above data is that genetic and environmental factors both play a role in determining the composition of essential oils of the Hypericum species studied.  相似文献   

3.
Available ethnobotanical information on Pteronia onobromoides (first recorded in 1685) indicates that the plant was once of considerable cultural and commercial importance and that it was powdered, mixed with fat, and applied to the skin for cosmetic and/or medicinal purposes. Sâb, as well as Son or San, are considered to be the original Nama names for this aromatic bush and also the origin of various names for San people, such as Sonqua and Bushman. A study of the leaf anatomy showed that essential oil is produced in globose oil glands situated below some of the vascular bundles in the spongy parenchyma, adjacent to the palisade parenchyma. The oil is relatively complex but contains a combination of myrcene, limonene, 1,8-cineole and p-cymene as main compounds, with smaller amounts of sabinene, trans-linalooloxide, linalool, terpinen-4-ol, α-terpineol, eugenol, thymol and α-phellandrene. Dichloromethane extracts exhibited antibacterial activity (especially against Staphylococcus epidermidis) with MIC values as low as 0.83 mg/ml. Other solvent extracts and the essential oil itself were less active. The results show that the traditional method of mixing powdered leaves with fat and applying it to the skin may have had deodorant, disinfectant and medicinal benefits.  相似文献   

4.
Widdringtonia is the only genus of the 16 genera of Cupressaceae present in South Africa. This genus is represented by three species in South Africa; W. nodiflora, W. schwarzii and W. cedarbergensis (= W. juniperoides) and the latter listed as critically endangered. Cedarwood oil (generally obtained from Juniperus species) is widely used as a fragrance material in several consumer products, however, no data has been published on the volatiles of the Clanwilliam cedar (W. cedarbergensis) native to South Africa. The essential oil composition of the wood and leaf oil isolated by hydro-distillation were analysed by GC–MS. The two oils were distinctly different. Twenty compounds representing 93.8% of the total oil were identified in the leaf oil which was dominated by terpinen-4-ol (36.0%), sabinene (19.2%), γ-terpinene (10.4%), α-terpinene (5.5%) and myrcene (5.5%). Twenty six compounds representing 89.5% of the total were identified in the wood oil with the predominance of thujopsene (47.1%), α-cedrol (10.7%), widdrol (8.5%) and cuparene (4.0%).  相似文献   

5.
Aeollanthus suaveolens Mart. ex Spreng belongs to Lamiaceae family, and in the Amazon this species is cultivated by natives’ people, this medicinal plant is popularly known as Catinga-de-mulata, being used by the population for general pain treatment. The present study analyzed the effects of light intensity on the anatomy, secretory structures, histochemistry and composition of essential oil of leaf and stem of A. suaveolens. The anatomical structure were observed in response to two light intensities, namely 50% (half shade, HS) and 100% (full sun, FS) light. Histochemical analyses were performed to detect lipids, essential oils, alkaloids, phenolic compounds, sesquiterpene lactones, mucilage, and tannins. Secretory structures were observed under a scanning electron microscope. The results obtained in the present work indicate that the light intensity can affect the histochemistry and structures of A. suaveolens. Cross sections of the leaves and stem revealed glandular trichomes on both leaf surfaces as well as the stem surface. Essential oil was detected by histochemical analyses in all types of secretory trichomes. These anatomical and histochemical responses suggest modifications to protect the photosynthetic apparatus from excess light, in addition we note that in the chemical composition of the essential oil the class of hydrocarbons sesquiterpene prevailed.  相似文献   

6.
A highly localised new species from the Cederberg Mountains near Wuppertal in the Western Cape Province is described. Annesorhiza asparagoides B.-E. Van Wyk, collected for the first time in 2009, differs from all other species of Annesorhiza (and the closely related Chamarea) in the unusual leaf structure, with crowded, subsessile, acicular leaf segments, resulting in dense, bottlebrush-like pinnae. The new species has a cluster of 10 or more slender roots, small (< 150 mm long), sparsely hairy leaves and small (± 8 mm long), oblong, conspicuously ribbed, homomericarpic fruits.  相似文献   

7.
Rhaponticum carthamoides (Willd.) Iljin is a perennial herb, commonly known as a maral root or Russian leuzea, which has been used for centuries in eastern parts of Russia for its marked medicinal properties. This review based on 117 literary sources, with many of them being originally published in non-English languages (mainly in Russian), discusses the current knowledge of traditional uses, chemistry, biological effects and toxicity of this species. Several different classes of compounds were previously isolated from various parts of R. carthamoides of which the main groups are steroids, particularly ecdysteroids, and phenolics (flavonoids and phenolic acids) accompanied with polyacetylenes, sesquiterpene lactones, triterpenoid glycosides and terpenes (essential oil). A comprehensive account of the chemical constituents is given in this review (figures of 120 structures are shown). Various types of preparations, extracts and individual compounds derived from this species have been found to possess a broad spectrum of pharmacological effects on several organs such as the brain, blood, cardiovascular and nervous systems as well as on different biochemical processes and physiological functions including proteosynthesis, work capacity, reproduction, and sexual function. Moreover, the extracts and preparations from the plant, which are hopefully safe, exhibited various additional biological effects e.g. antioxidant, immunomodulatory, anticancerogenic, antimicrobial, antiparasitic and insect antifeedant or repellent activities. The results of data analysis on the chemical, pharmacological and toxicological characteristics of R. carthamoides support the view that this species has beneficial therapeutic properties and indicate its potential as an effective adaptogenic herbal remedy. Finally, some suggestions for further research on chemical and pharmacological properties are given in this review.  相似文献   

8.
毛竹浸提液对苦槠幼苗生长的化感效应   总被引:1,自引:0,他引:1  
为探讨毛竹(Phyllostachys edulis)扩张过程中潜在的化感作用,选择苦槠(Castanopsis sclerophylla(Lindl)Schott)为研究对象。采用水浸提的方法,用毛竹茎叶、枯落物和土壤3部分浸提液浇灌苦槠幼苗,以蒸馏水处理作为对照,对比分析质量浓度分别为0.1、0.05、0.02 g/mL的3个浓度梯度浸提液处理下苦槠幼苗生长指标及各项光合生理指标的差异。结果表明,毛竹浸提液对苦槠幼苗苗高、地径和叶绿素相对含量的影响大体上呈现高浓度抑制低浓度促进的双重浓度效应。不同来源毛竹浸提液的化感效应不尽相同,土壤浸提液对苦槠幼苗生长和光合生理均呈现抑制作用,而茎叶、枯落物浸提液低浓度时为促进作用。毛竹潜在的化感作用,在其扩张过程中可能会干扰森林主要树种更新,从而对森林群落产生威胁。  相似文献   

9.
Multivariate analysis of leaf shape, anatomy, and Fourier-transform infrared (FTIR) data of 27 Camellia species with secretory structures (sects. Archecamellia, Stereocarpus, Furfuracea, Chrysantha), together with three species from related genera, Gordonia and Tutcheria (Theacea), was conducted to clarify some taxonomic problems. Our results show that crystals occurring in adaxial epidermal cells are firstly observed in Chrysantha species, and the secretory structures described are in fact cork warts. Furthermore, we introduce a form coefficient (F c) to assess the shape of epidermal cells, since they are usually irregular and difficult to describe. Pearson correlation analysis indicates that F c is useful to assess epidermal cell shape. Principal component analysis (PCA) of leaf shape indicates that two species from section Archecamellia and two species from section Stereocarpus are significantly different from those in section Furfuracea. Cluster analysis of FTIR data visualizes the degree of affinity among the 30 species examined here, which is consistent with the cluster analysis (CA) of anatomical data, as illustrated in the dendrogram. Therefore, our study indicates that integrated leaf characters based on leaf shape, anatomy, and FTIR data are useful in the taxonomic treatment of Camellia species with secretory structures. Taxonomic controversies among the Camellia species with secretory structures could thus be successfully addressed using only a few intact or small portions of leaves. Moreover, our results tend to support that Chrysantha species should not be merged into section Archecamellia, and that section Heterogenea should not be recognized in taxonomic treatments of Camellia species with secretory structures.  相似文献   

10.
The antifungal activities of cinnamon oil, clove oil, anise oil, and peppermint oil, and their main components (cinnamaldehyde, eugenol, trans-anethole, and menthol, respectively) against molds identified from areca palm leaf sheath (Mucor dimorphosporus, Penicillium sp., Aspergillus niger, and Rhizopus sp.) were investigated. An agar dilution method was employed to determine the minimum inhibitory concentration (MIC) of essential oils and their main components. Zone inhibition tests and the inhibitory effect of the leaf sheath dip-treated with essential oils against those molds were examined. Major components of essential oils on the leaf sheath during storage were quantified by gas chromatography analysis. The MIC values of essential oils on agar and on the leaf sheath were identical. With an MIC of 50 ??g ml−1, cinnamon oil had the strongest inhibitory effect. At their MICs the oils were capable of providing protection against mold growth on the leaf sheath for at least 12 weeks during storage at 25 °C and 100% RH. Scanning electron microscope examination showed that essential oils prevented spore germination. Except for menthol in peppermint oil, the main components of the essential oils, which were fairly stable over the storage period, largely contributed to the antifungal activity.  相似文献   

11.
Fifteen prenylated or geranylated flavanones and flavanonols were isolated from the leaf extracts of different Glycosmis species collected in Thailand and Malaysia. All structures were elucidated by spectroscopic methods, especially 1D and 2D NMR. Six compounds were described for the first time and two were only known so far as synthetic products. The chemotaxonomic significance of flavanoid accumulation within the genus Glycosmis is highlighted.  相似文献   

12.
荆条叶性状对野外不同光环境的表型可塑性   总被引:3,自引:0,他引:3  
杜宁  张秀茹  王炜  陈华  谭向峰  王仁卿  郭卫华 《生态学报》2011,31(20):6049-6059
光照是影响植物生长和分布的重要环境因子。对生长在野外5种不同光环境下(林外、阔叶林林缘、阔叶林林下、针叶林林窗和针叶林林下)的荆条的叶片进行取样研究,通过对光合作用光响应曲线、叶绿素荧光、叶绿素含量、叶片氮磷含量以及叶片形态的测量,来反映荆条对不同光环境的表型可塑性。研究结果表明,荆条叶片对于野外不同的光环境具有很好的适应机制,叶片功能性状受到结构性状的调节。低光下通过高的比叶面积(SLA)、单位质量叶绿素含量、光系统II最大量子产量,低的暗呼吸速率、光饱和点、光补偿点、叶绿素a,b的比值来提高对光能的利用效率,维持生长;高光下则通过与SLA有关的叶片结构的变化对光合作用进行调节。大多数的叶性状只受到日光照总量的影响,SLA的大小与日最高光强有关,可以对不同日变化模式的光照做出迅速的响应,是适应不同光照的敏感指标。尽管光照是不同光环境下影响荆条叶性状的主要环境因子,土壤养分含量同样会对叶性状产生影响,高土壤养分下的高叶长与叶柄长的比值体现了植物对资源获取和支撑结构之间分配的权衡。  相似文献   

13.
The leaf essential oils of 10 species of Ocotea (Lauraceae) from Monteverde, Costa Rica (Ocotea floribunda, Ocotea holdridgeana, Ocotea meziana, Ocotea sinuata, Ocotea tonduzii, Ocotea valeriana, Ocotea veraguensis, Ocotea whitei, and two undescribed species, Ocotea new species “los llanos”, and Ocotea new species “small leaf”) have been obtained by hydrodistillation and analyzed by GC–MS in order to discern the differences and similarities between the volatile chemical compositions of these species. The principal common constituents of the 10 species of Ocotea were α-pinene, β-pinene, β-caryophyllene, and germacrene-D.  相似文献   

14.
The essential oil composition from the aerial parts of a new Eryngium species from Australia, Eryngium rosulatum P.W. Michael ined., has been analysed by GC and GC/MS. A total of 34 compounds have been identified representing around 80% of the total oil. The main constituents of the oil were found to be β-elemene (16.0%) and bicyclogermacrene (12.5%). Other representative compounds were identified as δ-elemene (7.0%) and (E)-caryophyllene (5.9%). The sesquiterpene fraction (75.0%) was predominant in the essential oil of this species, most of these were hydrocarbons (53.8%). This paper represents the first study on this new, undescribed Australian species and its chemical composition.  相似文献   

15.
The geographical distribution and analysis of the essential oils of species from three sections of Hypericum L. (Guttiferae/Clusiaceae/Hypericaceae) from Portugal are presented. Hypericum perfoliatum (section Drosocarpium) grows wild in the centre and south of Portugal; Hypericum humifusum and Hypericum linarifolium are both from section Oligostema, the former occurring throughout the country, while the second is distributed mainly in the north and centre; Hypericum pulchrum (section Taeniocarpium) is confined to the littoral north of Portugal. The essential oils were obtained by distillation–extraction, hydrodistillation and distillation in a modified Marcusson apparatus from the dried aerial parts of the different populations and were analysed by GC and GC–MS. Monoterpene hydrocarbons constituted the main fraction in all oils (43–69%, 53–85%, 28–45% and 48–65% for H. perfoliatum, H. humifusum, H. linarifolium and H. pulchrum, respectively). Sesquiterpene hydrocarbons (2–13%, 6–18%, 21–27% and 16–18%, respectively) and a third fraction of non-terpenic compounds (20–29%, 3–16%, 2–14% and 5–11%, respectively) from the four species attained relatively high amounts in all oils. Within each species, no major differences were detected in the essential oil composition, despite the fact that different locations, phenological phases and extraction methodologies were used. Notwithstanding the dominance of α-pinene in all four species' oils, cluster and principal components analysis on the identified components showed that the range of α-pinene, β-pinene and n-nonane supported a separation of the four species. The essential oil composition of the four species showed some qualitative resemblances, which correlate well with the taxonomical classification based on morphological characters.  相似文献   

16.
The essential oils extracted from the embedded foliar secretory cavities of many Eucalyptus species are of economic value as pharmaceuticals and fragrance additives. Recent studies have indicated that Eucalyptus secretory cavities may not be exclusively involved in the biosynthesis and storage of essential oils. Therefore, we selected three species upon which to perform an examination of the contents of foliar secretory cavities: Eucalyptus froggattii, E. polybractea and E. globulus. This paper describes the isolation and structural characterization of two non-volatile glucose monoterpene esters, which we have named cuniloside B and froggattiside A, from within the secretory cavities of these species, and shows the presence of these compounds in solvent extracts of the leaves from two other species of Eucalyptus. Both compounds were found in high proportions relative to the essential oils extracted from the leaves. We propose that many other carbohydrate monoterpene esters previously isolated from bulk leaf extracts of various Eucalyptus species may also be localized within the non-volatile fraction of foliar secretory cavities.  相似文献   

17.
A new orchid, Disa albomagentea, is described from the Hottentots Holland Mountains in the Western Cape Province of South Africa. It is an obligately fire-dependent species closely related to Disa obtusa (sect. Disella), from which it can be easily distinguished by the larger flowers, i.e. galea 7-9 mm long versus 4-7 mm long, which are patent and bicoloured, i.e. magenta, white and not spotted versus purple brown, white to cream to greenish, and variously purple spotted. It appears to be endemic to seeps and marshes on the high peaks.  相似文献   

18.
A fungus causing zonate leaf blight diseases in various evergreen and deciduous woody plant species in Japan was characterized by a discoid multicellular propagule arising from a hyaline sclerotium-like structure in the leaf tissue and dark-coloured microconidia produced enteroblastically from the terminal cells on the surface of the discoid propagules. Myrioconium-like microconidiophores also producing microconidia were occasionally produced in culture. No teleomorphic characteristics were observed on the fungus. Molecular analysis based on the partial nu-rDNA sequence data revealed that the fungus was phylogenetically related to the Sclerotiniaceae, Leotiomycetes, and Ascomycota. Because the morphology and sequence data of this fungus does not coincide with those of any known anamorphic fungi, Haradamyces foliicola is proposed here as a new anamorphic genus and species for this fungus.  相似文献   

19.
The relative efficiency of incorporation of the exogenously supplied primary precursors [2-14C]acetate, [U-14C]glucose and [U-14C]sucrose into essential oil was determined in the immature leaves of threeCymbopogon species(C. martinii,C. winterianus andC. flexuosus). Acetate was most efficiently incorporated into essential oil inC. winterianus andC. flexuosus, whereas glucose was the best precursor inC. martinii. The observations are consistent when expressed as radioactivity [Bq] of essential oil per leaf, as percent incorporation or moles of precursors utilized for essential oil synthesis. Thus, there is selectivity in the efficiency of precursor utilization for the oil synthesis inCymbopogon species.  相似文献   

20.
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