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1.

Objective

Diterpene alkaloids are secondary plant metabolites and chemotaxonomical markers with a strong biological activity. These compounds are characteristic for the Ranunculaceae family, while their occurrence in other taxa is rare. Several species of the Spiraea genus (Rosaceae) are examples of this rarity. Screening Spiraea species for alkaloid content is a chemotaxonomical approach to clarify the classification and phylogeny of the genus. Novel pharmacological findings make further investigations of Spiraea diterpene alkaloids promising.

Results

Seven Spiraea species were screened for diterpene alkaloids. Phytochemical and pharmacological investigations were performed on Spiraea chamaedryfolia, the species found to contain diterpene alkaloids. Its alkaloid-rich fractions were found to exert a remarkable xanthine-oxidase inhibitory activity and a moderate antibacterial activity. The alkaloid distribution within the root was clarified by microscopic techniques.
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2.
An analysis of indicator values of four Saussurea DC. species, S. baicalensis (Adams) B. L. Rob., S. frolowii Ledeb., S. salicifolia (L.) DC., and S. schanginiana (Wydl.) Fisch. ex Serg., have been carried out by the method of indicator scales of soil moisture and nutrient availability and salinity in more than 1600 relevés. The size of their ecological ranges and the values of their competitiveness in phytocenoses are determined. As a result of a comparison of the locality of local populations within the ecological range and their occurrence, the vulnerability of S. baicalensis, S. frolowii, S. salicifolia, and S. schanginiana in the Kuznetsk Alatau is evaluated. The types of rarity for these species in the Kuznetsk Alatau are determined.  相似文献   

3.
Fossil leaves and associated reproductive structures from the Kundur locality, Amur Region, are examined. A new genus of the unlobed platanaceous leaves, Kunduriphyllum gen. nov. (Platanaceae) is described based on distinctive morphological and epidermal features. The similarity of epidermal characteristics and identical biological damage suggest that the leaves Kunduriphyllum kundurense gen. et comb. nov., staminate inflorescences Kundurianthus, and infructescences Kunduricarpus could be assigned to a single plant.  相似文献   

4.
The history of studying the genus Diaphorus is described. Seventeen species have been studied. A key to species of the genus Diaphorus of the Palaearctic fauna, including 37 species, and a catalogue of the Palaearctic species with synonyms are given. Diaphorus oldenbergi Parent, 1925 is regarded as a synonym of the species D. nigrotibia Strobl, 1893 (syn. n.). The new species Diaphorus sublautus sp. n. from Azerbaijan is described. Lectotypes of D. dolichocercus Stackelberg, D. parenti Stackelberg, D. ussuriensis Stackelberg, and D. varifrons Becker are designated.  相似文献   

5.
The photosynthetic rate, light saturation point, light compensation point, changes in the MDA and SOD activities, and protein expression of two different drought-resistance species, Spiraea fritschiana and Spiraea trichocarpa, were assessed in this study. Furthermore, the drought-resistant physiological mechanisms of both species were analyzed at the protein level. The photosynthetic capacities of two Spiraea species decreased under drought stress, and the light saturation point and light compensation point decreased. However, their capacities to use weak light increased. Spiraea fritschiana, which demonstrated a stronger drought resistance, showed a better ability to adapt to weak light than S. trichocarpa. The content of MDA in S. fritschiana was notably lower than that in S. trichocarpa, indicating that the concentration of the membrane peroxidation products of S. fritschiana was less than those of S. trichocarpa. Compared with S. trichocarpa, S. fritschiana’s SOD activity was higher, and its ability to remove ROS was also better. Sixty-six proteins were identified with significantly different expression behavior and included regulatory, redox homeostasis, metabolism and energy, and cytoskeleton proteins. The results showed that the photosynthesis of S. trichocarpa was significantly affected by the drought stress. Enzymes in photosynthesis changed significantly; the expression of the RuBisCo large subunit decreased; and RuBisCo carboxylase, the chlorophyll a–b binding protein, ATP synthase, OEC 33 kD photosystem II protein and 23 kD OEC protein greatly increased. In addition, four antioxidant enzymes greatly increased, GroES chaperonin decreased, and eIF5A significantly increased under light stress. When S. fritschiana Schneid encountered serious drought stress, in addition to those enzymes that changed significantly under light drought stress in S. trichocarpa Nakai, NAD(P)H-quinone oxidoreductase and eIF5A were up-regulated. Specifically, three heat-shock proteins were induced. The expression of the enzymes of the two Spiraea that were related to photosynthesis, oxidation–reduction and regulation were all affected, but their species and expression patterns were different. In S. trichocarpa Nakai and S. fritschiana Schneid, there were significant changes in the proteins related to energy metabolism and the proteins related to energy transport, respectively. Thus, we considered that, in the case of protein involvement, the differences in the metabolic pathways and adjustment levels might contribute to S. trichocarpa having a weaker drought tolerance than S. fritschiana.  相似文献   

6.
Nowadays, a search for sources of the most biologically active antioxidant compounds among various herbs is an urgent problem. In this connection, several succulent plants from the Aloe genus are of special interest, because their preparations are widely used in domestic medicine. In this study, we measured the antioxidant activity (AOA) of an alcoholic extract of leaves of 15 Aloe species by amperometric and chemiluminescent methods and performed a comparative analysis of the results. We observed a considerable difference between the AOA values for the several Aloe species and explained this fact. The most active antioxidant among the samples proved to be the A. pillansii representative of the Aloe genus. Both methods demonstrated that the extracts from leaves of this Aloe species exhibited the high AOA. The A. broomii and A. spinosissima also had rather high AOA along with the A. pillansii and A. arborescens. The newly discovered Aloe species could be as promising a source of biologically active compounds as the traditionally used A. arborescens and A. vera.  相似文献   

7.
Taxus media is an important species in the family Taxaceae with high medicinal and commercial value. Overexploitation and illegal trade have led T. media to a severe threat of extinction. In addition, T. media and other Taxus species have similar morphological traits and are easily misidentified, particularly during the seedling stage. The purpose of this study is to develop a species-specific marker for T. media. Through a screening of 36 start codon targeted (SCoT) polymorphism primers, among 15 individuals of 4 Taxus species (T. media, T. chinensis, T. cuspidate and T. fuana), a clear species-specific DNA fragment (amplified by primer SCoT3) for T. media was identified. After isolation and sequencing, a DNA sequence with 530 bp was obtained. Based on this DNA fragment, a primer pair for the sequence-characterized amplified region marker was designed and named MHSF/MHSR. PCR analysis with primer pair MHSF/MHSR revealed a clear amplified band for all individuals of T. media but not for T. chinensis, T. cuspidate and T. fuana. Therefore, this marker can be used as a quick, efficient and reliable tool to identify T. media among other related Taxus species. The results of this study will lay an important foundation for the protection and management of T. media as a natural resource.  相似文献   

8.
Two new species of Arachnothryx (Guettardeae, Rubiaceae) from the cloud forest of the Sierra Norte of Oaxaca, Mexico are described and illustrated. Arachnothryx axillaris together with A. heteranthera are the only two species in the genus with axillary inflorescences, but otherwise they are not similar. The new species is more similar to A. capitellata, but it differs in pubescence and inflorescence morphology. Arachnothryx flores-olverae can be confused with A. buddleioides mainly because they share discolorous leaves with densely tomentose pubescence, but they differ in stipule and inflorescence morphology. With these two new species the Sierra Norte of Oaxaca becomes more evidently the main hotspot of species diversity for the genus.  相似文献   

9.
Central European wet meadows are diminished by abandonment of cultivation measures, drainage, pollution, intensive agriculture and climate change during the last decades. In addition, original wet meadow communities can be threatened by immigrating neophytes. Typical invasive species in wet meadows are the steeplebushes Spiraea tomentosa and Spiraea douglasii, but their impact on the indigenous arthropod fauna is unknown. The present study therefore investigates Spiraea-induced changes in ground- and herb dwelling spiders in Spiraea sites, uncultivated meadows with interspersed Spiraea sp. and mowed meadows without Spiraea sp. using pitfall traps and sweep netting. Light intensity, vegetation height and coverage differed significantly between the Spiraea sites and the mowed meadows. In consequence, the activity density of ground-dwelling spiders was much lower in the Spiraea sites and their habitat preferences differed significantly from the two meadow types. Species preferring forests and forest edges were more abundant in invaded sites whereas specimens preferring open habitats decreased. Although the vegetation height and coverage of mowed meadows and cultivated meadows did not differ remarkably, uncultivated meadows contained less spiders of open dry habitats whereas forest species increased. In contrast, differences between herb dwelling spider assemblages of the three habitat types were not significant. Based on the results of the project, the risk of steeple bush invasion and management methods of wet meadows are discussed.  相似文献   

10.
11.
A new species of Stemodia (Plantaginaceae) from the Caatinga of northern Minas Gerais, Brazil, is described and illustrated. Stemodia perfoliata was first collected by Auguste de Saint-Hilaire, ca. 200 years ago, and remained unnamed until now. The new species is characterized by the connate-perfoliate leaves, a unique feature in the genus. We provide notes on morphology, geographic distribution and conservation status of S. perfoliata, along with a key to differentiate it from the similar species that occur in Brazil: S. durantifolia, S. hyptoides, S. maritima, S. palustris and S. stricta.  相似文献   

12.
Till this day, there is not much known about the phylogeny of the Secale genus; therefore, in our research, we tried to shed some lights on the issue of rye (Secale genus) taxonomy. The genetic diversity and phylogenetic relationships were evaluated using 13,842 DArTseq? polymorphic markers. The model-based clustering (STRUCTURE software) separated our 84 samples into three main clusters: perennial cluster, annual cluster, and S. sylvestre cluster. The same result was obtained using Neighbour Joining tree and self-organizing maps. Secale sylvestre, S. strictum, and S. cereale are the three main species of the Secale genus. Three samples of rye are in basal positions in phylogenetic trees. These accessions share ancient morphological characters and are probably the ancestors of different lineages within Secale. Annual Secale taxa, with the exception of S. sylvestre, create one mutual taxon. We have found out that the semi-perennial taxa of S. cereale var. multicaule and S. strictum subsp. ciliatoglume are genetically closest to the annual species of S. cereale. Phylogenetic signals for semi-perennial and annual taxa are also present in S. strictum subsp. africanum. SNP-based analysis revealed that evolution of annual S. cereale has already begun in S. strictum subsp. africanum. The results showed that S. vavilovii cannot be considered as a separate species but a subspecies of S. cereale Secale cereale subsp. dighoricum is a hybrid. It is still not clear whether we can consider S. strictum subsp. strictum and S. strictum subsp. kuprijanovii as two separate species.  相似文献   

13.
Five species of the hyalinatus species-group of the genus Sphecodes Latreille 1804 (Hymenoptera, Halictidae) are reviewed. Sphecodes maruyamanus Tsuneki and S. murotai Tsuneki are found in Russia for the first time, and S. hyalinatus Hagens is newly recorded from the Kuril Islands (Kunashir). Illustrated keys to males and females of all the species of the S. hyalinatus species-group are provided. An updated checklist of 37 species of the genus Sphecodes is given.  相似文献   

14.
The composition and distribution of the species of the genus Scalaspira Conrad, 1862 in the Eocene-Oligocene of western Kazakhstan are revised. Following Tembrock we assign this genus to Buccinidae and synonymize Aquilofusus Kautsky, 1925 with it. The stratigraphic interval studied contains at least eight species. Three species are new: S. alexeevi (Middle? and Upper Eocene, Chegan Formation), S. korobkovi, and S. kumsuatensis (Upper Oligocene, Karatomak Beds).  相似文献   

15.
16.
The review presents the results of scientometric analysis of data on the level of study and chemical diversity of flavonoids of the Scutellaria L. genus species of the world’s flora. Flavonoid composition in 63 species of skullcap is reported, together with the data on distribution in plants, structure, and sources of 301 flavonoids belonging to the groups of flavones, flavanones, flavanonols, flavonols, chalcones, isoflavones, flavolignans, and bioflavonoids. The greatest number of flavonoids was shown to be isolated from plants of S. indica, S. baicalensis, S. barbata, S. amoena, S. prostrata, S. galericulata, S. discolor, S. ramosissima, and S. supina. Scientometric studies indicate the constantly growing interest in the study of species of the Scutellaria L. genus by scientists of various branches of science, including phytochemists, biologists, and pharmacologists. Information provided in the review can be used to address issues of chemosystematics of plants of the Scutellaria L. genus.  相似文献   

17.
The genus Phaeophilacris Walk. is divided into two subgenera: Phaeophilacris s. str. and Speluncacris Sjöst. The latter name, originally proposed as a generic one and synonymized with Phaeophilacris s. l., is restored as a subgeneric name. The former genera Opilionacris Sjöst. and Cavernacris Sjöst. previously synonymized with Phaeophilacris s. l. are considered as synonyms of the subgenus Speluncacris. Four new species (Ph. (S.) malawi sp. n., Ph. (S.) boldyrevi sp. n., Ph. (S.) dmitrievi sp. n., and Ph. (S.) gigantea sp. n.) and three new subspecies (Ph. (S.) bredoides mangochi subsp. n., Ph. (S.) bredoides mutinondo subsp. n., and Ph. (Ph.) townsendi aethiopica subsp. n.) of the genus Phaeophilacris are described.  相似文献   

18.
19.
One new genus, two new subgenera, and eight new species from Ecuador, Brazil, and Venezuela are described. The former genus Hattersleya Nischk et Otte is considered as a subgenus of the genus Neoacla Des. Acla multivenosa Chop., A. reticulata Chop., A. vicina Chop., Selvacla choreutes Otte, S. salvator Otte, S. alsiosus Otte, and S. sophos Otte are transferred to the genus Neoacla, and Desutteria epiplatys Nischk et Otte, to the genus Silvastella Des.-Gr. New data on the geographical and ecological distribution of some species are given.  相似文献   

20.
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