Astragalus Species Research Articles

Phenotypic and genetic diversity of rhizobia isolated from nodules of the legume genera Astragalus, Lespedeza and Hedysarum in northwestern China

Twenty-nine rhizobial isolates from root nodules of the wild Legumes Astragalus, Lespedeza and Hedysarum growing in the northwestern region of China, were characterized by numerical taxonomy, RFLP and sequencing of PCR-amplified 16S rDNA genes, and cross-nodulation with selected Legume species. Based on the results from numerical taxonomy, the isolates could be divided into two main groups (Clusters 1 and 2) and some single isolates at 82% similarity. CLuster 1 contained six isolates from Astragalus, Lespedeza and Hedysarum spp. Cluster 2 consisted of nine isolates from Astragalus and Hedysarum species. The phytogenetic analysis based on 16S rRNA gene sequences showed that SH199, representing cluster 1, belonged to the Rhizobium-Agrobacterium group, and SH290B, representing cluster 2, was closely related to R. galegae and R. huautlense.

Taxonomic and Distributional Notes on Some Astragalus L. (Fabaceae) in India

In this study the revised distribution records of 25 species of Astragalus L. in India has been provided along with correct nomenclature and taxonomic notes. In addition, the relationship, conservation status and Cibachrome photographs of the type materials for some species have also been included wherever found necessary. Based on field and herbarium studies nine species (i. e. A. alitschuri B. Fedtsch, A. charguschanus Freyn, A. contortuplicatus L., A. flemingii Ali, A. iodotropis Boiss. & Hohen, A. pyrrhotrichus Boiss., A. subumbellatus Klotz., A. stocksii Bunge, A. zacharensis Bunge) have been excluded, as they do not occur in the present political boundaries of India of 1971. Those species have also been discussed here which have been recently transferred from Astragalus to some other genera like Ophiocarpus (Bunge) Ikonn., Podolotus Benth. and Podlechiella Maassoumi & Kaz. Osaloo. The present investigation also reveals that about 12 species are not represented in Indian herbaria, while they have been recorded from India based on very old collections housed at different foreign herbaria. A new combination Caragana aegacanthoides (Parker) Chaudhary & Srivastava has been proposed based on Astragalus aegacanthoides Parker.

The use of seed proteins as revealed by SDS-PAGE in the taxonomy of some Astragalus species (Fabaceae)

T otal seed proteins of 20 Astragalus L. species belonging to 16 sections were electrophoretically analyzed using SDS-PAGE technique. Multivariate analysis (cluster and principal coordinate analysis) of the electrophoretic data showed heterogeneity between some taxa. This heterogeneity was discussed on the light of the controversy over the taxonomic position of Astragalus L. species. The relationships among the examined taxa have been demonstrated as cluster tree using SYSTAT-pc software. This tree illustrated that the studied taxa were separated into two major groups, the New World and the Old World species. The New World group include the species Astragalus wootoni, A. allochrous, A. palmeri, A. layneae, A. lentiginosus, A. nothoxys, A. minthorniae and A. nuttallianu. However , Astragalus coccineus, A. pectinatus and A. didymocarpus that considered from the New World, but separated in the Old World group. Astragalus layneae separated from the rest taxa in the New World group. This species was located in a separate section layneani. TheOld World group divided into three subgroups and discussed on the light of earlier classification.

Fatty acid composition of some Astragalus species from Turkey

In this study, the fatty acid contents of some Astragalus L. (Fabaceae) species from Turkey were determined by GC and GC-MS techniques. The seed oils of Astragalus sp. (A. echinops Aucher ex. Boiss., A. subrobustos Boriss., A. jodostachys, Boiss. & Buhse., A. falcatus Lam., A. fraxinifolius DC.) contained linolenic (between 23–41.%), linoleic (23–37%), and oleic acids (8–19%) as the major components. Fatty acid composition of the studied Astragalus taxa showed uniform fatty acid patterns. Palmitic and stearic acids were the major saturated fatty acids in the seed oils. The amounts of unsaturated fatty acids were higher than saturated fatty acids.

Taxonomy and floristic geographical distribution of the Chinese medicinal Huangqi

It is indicted definitely that the Chinese medicinal Huangqi plants have 3 species——Astragalus membranaceus(Fisch.) Bunge,A.mongholicus Bunge and A.brealimongolicus Y.Z.Zhao which is a new species;It is defined the floristic geographical elements of the 3 species: A.membranaceus is distributional species of the forest zone of northern east Asia-southern Siberia,A.mongholicus is distributional species of the forest-steppe zone of northern China,A.borealimongolicus is distributional species of steppe zone of northern Mongol Plateau; It is found that 3 species form obvious distribution pattern of geographical substitute.

Use of Fluorometry to Differentiate Among Clipped Species in the Genera Astragalus, Oxytropis, and Pleuraphis

A rapid and reproducible method to determine botanical composition of forage is an ecological and economic goal for range animal ecologists. Multidimensional fluorometry previously demonstrated the possibility of a unique optical approach for accurately determining species composition of clipped and digested plant materials. Fluorometry may be used to detect toxic plants in standing crop as well as diets by using electronic transitions in chemical structures at wavelengths between 370 and 580 nm. Grass hay (genus Pleuraphis) and 6 clipped forbs (4 species of Astragalus and 2 species of Oxytropis) were examined. The resulting spectral signatures were evaluated for differences in the blue and green regions of the visible spectrum using Principal Component Analysis (PCA). This represents the first published data using chemometrics to differentiate among fluorophores from these plant extracts. It was possible to distinguish between the grass and forbs and among forbs. Further research will be required to evaluate these same plant species in mixed diets and fecal samples.

Simultaneous analysis of seven astragalosides in Radix Astragali and related preparations by liquid chromatography coupled with electrospray ionization time‐of‐flight mass spectrometry

A method has been developed for the qualitative and quantitative analysis of pharmacologically active astragalosides isolated from several species of the genus Astragalus by high performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry. Seven astragalosides in Radix Astragali and their commercial pharmaceutical preparations were analyzed using the developed method. The extracted ion current chromatograms were obtained from the total ion current chromatogram using the m/z of [M+Na]+ ions produced by target compounds for peak determination. The limits of detection and limits of quantification were in the range of 0.10-0.22 ng and 0.22-0.52 ng in full scan mode, respectively. All calibration curves showed good linear regression (r2 > or = 0.9965) within the test range. The overall intra- and inter-day precision was less than 2.86% for peak area and the accuracy was higher than 92.9% on using ginsenoside I as internal standard. The assay was successfully utilized to analyze the major biologically active astragalosides in six samples of Astragalus membranaceus (Fisch.) Bge var. mongholicus (Bge.) Hsiao. and eight commercial preparations. The overall results demonstrate that this method is simple, selective, and suitable for the quality control of Chinese medicine and their preparation in the low nanogram range.

Bee Associates of Flowering Astragalus and Onobrychis Genebank Accessions at a Snake River Site in Eastern Washington

A 3 yr survey of the bee associates of flowering accessions of Astragalus and Onobrychis species was conducted in open-pollinated field nurseries at Central Ferry, Washington to gain insight into the potential for bee-mediated inter-accession out-crossing in these nurseries. Such nurseries are used by genebank managers at the USDA-ARS Western Regional Plant Introduction Station (WRPIS), Pullman, Washington, to multiply seed of accessions low in viability and/or supply. Fifty-two species of bees (Hymenoptera) in the Andrenidae (4 species), Apidae (18), Colletidae (1), Halictidae (5), and Megachilidae (24) were recorded. Species-rich genera were Bombus (8 species) and Osmia (16). One undescribed species of Osmia was collected. The bee fauna was more diverse on Astragalus (45 bee species) compared to Onobrychis (29 species). Among the 24 Astragalus and 13 Onobrychis species censused, bee diversity was highest on A. bungeanus Boiss. (24 bee species), A. chaborasicus Boiss. & Hausskn. (24 species), A. miser var. serotinus (A. Gray ex J.G. Cooper) Barney (14 species), A. cicer L. (13 species), A. schistosus Boiss. & Hohen. (12 species), A. onobrychis L. (11 species), A. podolobus Boiss. & Hohen. (11 species), and Onobrychis viciifolia Scop. (10 species). The presence of a rich bee fauna in WRPIS nurseries at Central Ferry, including documented pollinators of the allogamous species A. cicer and O. viciifolia, could complicate efforts to prevent hybridization and maintain genetic integrity of genebank accessions of allogamous plant species. Our results support a 1993 decision by WRPIS curators to discontinue the practice of clustering accessions of single species of Astragalus and Onobrychis in open-pollinated nurseries to regenerate seed.

RAPD and FAME analyses of Astragalus species growing in eastern Anatolia region of Turkey

Fatty acid (FAs) and RAPD profiles were used to examine phenotypic and genetic relationships between eight Astragalus species including Astragalus maximus Willd. var. maximus, Astragalus coadunatus Hub. Mor. & Chamb., Astragalus kurdicus Boiss. var. kurdicus, Astragalus lagurus Willd, Astragalus christianus L., Astragalus cicer L., Astragalus atrocarpus Champ & Matthews and Astragalus onobrychioides Bieb., which were wildly growing in eastern Anatolia region of Turkey. All of the eight Astragalus species tested in this study were separated based on the presence and composition of 45 different FAs. Four of the Astragalus species including A. coadunatus, A. lagurus, A. christianus, and A. atrocarpus were rich in terms of FA contents containing at least 22–31 different FAs. The relative proportions of two fatty acids, 16:0, and 18:1:ω8c were higher in these four Astragalus species. The remaining species have limited number of FAs with unique FAMEs profiles. Six of the 10 decamer primers examined were selected to find out genetic polymorphism in Astragalus species. A total of 98 polymorphic bands were observed, ranging in size from 250 bp to 3000 bp. The RAPD results suggested that A. atrocarpus, A. onobrychioides and A. kurdicus are closely related and completely different from the other species. Six genetically distinct groups were found among the species of Astragalus. High genetic variations among Astragalus species growing wildly in eastern Anatolia region of Turkey may imply the differences in their origins. The results in the present study suggested that both RAPD and FA analyses are useful for differentiation of Astragalus species.

Use of Fluorometry to Differentiate Among Clipped Species in the Genera Astragalus, Oxytropis, and Pleuraphis

A rapid and reproducible method to determine botanical composition of forage is an ecological and economic goal for range animal ecologists. Multidimensional fluorometry previously demonstrated the possibility of a unique optical approach for accurately determining species composition of clipped and digested plant materials. Fluorometry may be used to detect toxic plants in standing crop as well as diets by using electronic transitions in chemical structures at wavelengths between 370 and 580 nm. Grass hay (genus Pleuraphis) and 6 clipped forbs (4 species of Astragalus and 2 species of Oxytropis) were examined. The resulting spectral signatures were evaluated for differences in the blue and green regions of the visible spectrum using Principal Component Analysis (PCA). This represents the first published data using chemometrics to differentiate among fluorophores from these plant extracts. It was possible to distinguish between the grass and forbs and among forbs. Further research will be required to evaluate these same plant species in mixed diets and fecal samples.

Ecology of two geographically restricted Astragalus species (Fabaceae), A. bibullatus and A. tennesseensis, of the eastern United States

Abstract Jerry M. Baskin (Department of Biology, University of Kentucky, Lexington, KY, 40506-0225, U.S.A.; jmbask0@uky.edu) & Carol C. Baskin (Department of Biology, University of Kentucky, Lexington, KY, 40506-0225, U.S.A.; ccbask0@uky.edu and Department of Plant and Soil Science, University of Kentucky, Lexington, KY, 40546-0321, U.S.A.). Ecology of two geographically restricted Astragalus species (Fabaceae), A. bibullatus and A. tennesseensis, of the eastern United States. Brittonia 57: 345–353. 2005.—Astragalus bibullatus is endemic to limestone glades in the Central Basin of Tennessee, and except for one population in Illinois, A. tennesseensis is endemic to limestone glades in the Central Basin and in the Moulton Valley of Alabama. However, A. tennesseensis has been extirpated from four counties in Illinois, from its only known site in Indiana, from one county in Tennessee, and from one county in Alabama. Astragalus bibullatus is closely related to the geographically widespread Great Plains taxon A...

Spine anatomy and its systematic application in Astragalus sect. Rhacophorus s. L. (Fabaceae) in Iran

Cross sections of petioles in 35 species of Astragalus mainly belonging to sect. Rhacophorus were studied for circumscription of natural groups within the section and reliable characters in delimiting polymorphic species. The following characters were determined to be informative: number of parenchymatous cell layers in pith, diameter of median sclerenchymatous vascular bundle sheath and diameter of the cross section as whole. Astragalus amblolepis, A. andalanicus, A. floccosus, A. meyeri, A. paralipomenus, A. pycnocephalus and A. stenolepis are characterized by large pith and relatively large sclerenchymatous bundles. Most of these species belong to sect. Rhacophorus s. str., comprising large-flowered species as circumscribed by some taxonomists, but few species of sects. Stenonychium and Platonychium also show these features. Our results show that spine anatomy is not useful for circumscribing sections in spiny Astragalus, but applicable in delimiting small natural groups and circumscribing species.

Volatiles from Four Astragalus Species: Phenological Changes and their Chemotaxonomical Application

This paper shows the changes of the volatile compounds from four Astragalus species at three phenological stages: leaf development, flowering and fructification, which might be connected with the plant defense. After GC/MS analyses of Astragalus glycyphyllos L., A. hamosus L., A. cicer L. and A. spruneri Boiss., different groups of volatile compounds were found: hydrocarbons, alcohols, aldehydes and ketones, esters, terpenes, chlorinated compounds, etc. Identified volatiles were used for a cluster analysis in order to make chemotaxonomic conclusions for these evolutionary different species.

Analysis of sulfur and selenium assimilation in Astragalus plants with varying capacities to accumulate selenium

Several Astragalus species have the ability to hyperaccumulate selenium (Se) when growing in their native habitat. Given that the biochemical properties of Se parallel those of sulfur (S), we examined the activity of key S assimilatory enzymes ATP sulfurylase (ATPS), APS reductase (APR), and serine acetyltransferase (SAT), as well as selenocysteine methyltransferase (SMT), in eight Astragalus species with varying abilities to accumulate Se. Se hyperaccumulation was found to positively correlate with shoot accumulation of S-methylcysteine (MeCys) and Se-methylselenocysteine (MeSeCys), in addition to the level of SMT enzymatic activity. However, no correlation was observed between Se hyperaccumulation and ATPS, APR, and SAT activities in shoot tissue. Transgenic Arabidopsis thaliana overexpressing both ATPS and APR had a significant enhancement of selenate reduction as a proportion of total Se, whereas SAT overexpression resulted in only a slight increase in selenate reduction to organic forms. In general, total Se accumulation in shoots was lower in the transgenic plants overexpressing ATPS, PaAPR, and SAT. Root growth was adversely affected by selenate treatment in both ATPS and SAT overexpressors and less so in the PaAPR transgenic plants. Such observations support our conclusions that ATPS and APR are major contributors of selenate reduction in planta. However, Se hyperaccumulation in Astragalus is not driven by an overall increase in the capacity of these enzymes, but rather by either an increased Se flux through the S assimilatory pathway, generated by the biosynthesis of the sink metabolites MeCys or MeSeCys, or through an as yet unidentified Se assimilation pathway.

Correction to an effectively but non-validly published species of Astragalus (Leguminosae) from New Mexico

On page page 839 of A Utah Flora, ed. 3 (October 1993; Monte L. Bean Life Science Museum, Brigham Young University, Provo, Utah), a name was effectively but not validly published, due to inadvertent lack of a Latin diagnosis. That error is herein corrected and the name validated. The complete citation appears below. The new species of Astragalus is a tall, rush-like plant, 3-6 dm tall, from McKinley County, New Mexico. Its pods similar to those of A. wingatanus.

Growth inhibition of rhizobia isolated from arctic legumes (Astragalus and Oxytropis spp.) and sainfoin (Onobrychis viciifolia) by sainfoin seed diffusates

Cold-adapted arctic rhizobia (from Astragalus and Oxytropis species) were used in nodulation studies and field inoculation trials with a temperate forage legume, sainfoin (Onobrychis viciifolia), since they have the potential to improve symbiotic nitrogen fixation at low temperatures. A major concern in legume inoculation is the toxicity of seed and root tannins to rhizobia. We studied the effects of sainfoin seed diffusates on the growth of 47 arctic and 2 sainfoin strains of rhizobia. Growth of all tested strains on yeast-extract mannitol agar plate was inhibited to various degrees by sainfoin seed diffusates. There was no correlation between the zone of inhibition and the symbiotic effectiveness of each strain on sainfoin. However, growth inhibition was totally reversed by the addition of iron as Fe-EDTA in the agar medium. In liquid medium without iron, growth inhibition of an arctic strain was 94% after 4-day growth. With the addition of 100 µM Fe-EDTA, inhibition was only 5%, and with 100 µM Fe-citrate, 76 %. These results underline the importance of evaluating the toxicity effect under normal rhizospheric conditions.

Effects of triterpene saponins from Astragalus species on in vitro cytokine release

Roots of Astragalus species are used to treat leukemia and for wound healing in Turkish folk medicine. In order to evaluate this information, the effect of 13 cycloartane- and 1 oleanan-type triterpene saponins isolated from Turkish species ( Astragalus brachypterus, Astragalus cephalotes, Astragalus microcephalus, and Astragalus trojanus), as well as methanol extracts from the roots of three Astragalus species ( Astragalus cephalotes, Astragalus oleifolius and Astragalus trojanus) were studied. Cytokine concentrations of interleukins IL-1β, IL-8 and TNF-α after bacterial lipopolysaccharide (LPS) and IL-2, IL-4 and INF-γ after phorbolacetate (PHA) stimulation were determined using commercial enzyme-linked immunosorbent assay (ELISA) kits. All triterpene saponins tested in the present study showed a prominent IL-2 inducing activity between 35.9% and 139.6%. Among the extracts the highest score was obtained for Astragalus oleifolius (141.2%). Glycosides of 20,24-epoxy and 20,25-epoxy cycloartanes showed higher IL-2 inducing activity than those of acyclic-cycloartane derivatives as well as aglycone of 20,24-epoxy cycloartanes, cycloastrogenol. Especially the activity of Astragaloside VII, a tridesmosidic glycoside of cycloastrogenol, was the most remarkable. The oleanan-type triterpene saponin also showed a prominent IL-2 inducing activity. IL-2 is a cytokine produced by activated T cells, which has shown powerful immunostimulatory and antineoplastic properties. Accordingly, the IL-2 inducing activity of the triterpene saponins might be the mechanism involved in order to explain the immunomodulatory and anticancer effects of Astragalus species.

Biomedical Applications of Poisonous Plant Research

Research designed to isolate and identify the bioactive compounds responsible for the toxicity of plants to livestock that graze them has been extremely successful. The knowledge gained has been used to design management techniques to prevent economic losses, predict potential outbreaks of poisoning, and treat affected animals. The availability of these compounds in pure form has now provided scientists with tools to develop animal models for human diseases, study modes of action at the molecular level, and apply such knowledge to the development of potential drug candidates for the treatment of a number of genetic and infectious conditions. These advances are illustrated by specific examples of biomedical applications of the toxins of Veratrum californicum (western false hellebore), Lupinus species (lupines), and Astragalus and Oxytropis species (locoweeds).

Isozyme variation in some populations of a rare endemic species Astragalus submitis (Fabaceae) in Iran

Fresh leaves of 67 individuals belonging to 9 populations representing 5 morphs and two subspecies of Astragalus submitis, a rare endemic species in north Iran, were analyzed in respect to isozyme banding pattern. A total of 20 bands from three enzyme systems were recorded. The mean number of bands per presumed isozyme ranges from 3–3.3. The value of a Euclidean distance ranges from 0.265 to 1.281. The average value of H′, estimated for each population, ranged from 0.298 to 0.371. Data analysis was done using clustering method UPGMA. On the basis of Euclidean distance, the obtained dendrogram supports the recognition of A. submitis subsp. maassoumii as separate taxon, which is in agreement with morphological data.

Molecular systematics of the genus Astragalus L. (Fabaceae): Phylogenetic analyses of nuclear ribosomal DNA internal transcribed spacers and chloroplast gene ndh F sequences

Comparative sequencing of internal transcribed spacers (ITS) and 5.8S gene of nuclear ribosomal DNA was carried out to examine phylogenetic relationships among subgenera and sections of Old World Astragalus as well as the recent segregate genera Barnebyella and Ophiocarpus. For a subset of these taxa (43 accessions), the nrDNA ITS data were supplemented by sequences from the chloroplast ndhF gene. Phylogenetic trees resulting from separate analyses of the nrDNA ITS and ndhF sequences were in conflict mainly on the position and relationships of Ophiocarpus aitchisonii, Astragalus hemsleyi, A. grammocalyx, A. coelicolor, A. capito, A. epiglottis and A. annularis. Excluding these taxa, phylogenetic analysis of a combined nrDNA ITS-ndhF data matrix was also conducted, so that in the resulting tree, most clades were more resolved and better statistically supported than those were in the separate analyses. Our results indicate that the monotypic segregate genera Barnebyella (= A. migpo), Ophiocarpus (= A. ophiocarpus) and morphologically isolated annual species A. dipelta (= Didymopelta turkestanica), A. schmalhausenii (= Sewerzowia turkestanica) and A. vicarius (= S. vicaria) are clearly nested within Astragalus. Our results confirm earlier studies that shows A. vogelii is allied with the genera Colutea and Oxytropis rather than with any Astragalus species. It is therefore excluded from Astragalus and elevated to the new generic rank and named as Podlechiella Maassoumi and Kazempour Osaloo. None of the eight traditionally recognized Astragalus subgenera Epiglottis, Trimeniaeus, Phaca, Hypoglottis, Calycophysa, Tragacantha, Cercidothrix and Calycocystis are monophyletic. Similarly, the monophyly of Podlech’s new subgenera Trimeniaeus, Astragalus and Cercidothrix is not supported. Among the many species-rich sections analyzed here, only Cenanthrum, Chronopus, Laxiflori, Lotidium, Incani and Amodendron are monophyletic.