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Karl Wah Keung Tsim - One of the best experts on this subject based on the ideXlab platform.
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phylogeny of Astragalus in china molecular evidence from the dna sequences of 5s rrna spacer its and 18s rrna
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Tina T X Dong, Clarles Clarke, Zong H Song, Zhaoning Ji, Chunkeung Lo, Karl Wah Keung TsimAbstract:Radix Astragali (root of Astragalus; Huangqi) is a traditional Chinese medicine commonly used as an immunostimulant, hepatoprotective, diuretic, antidiabetic, analgesic, expectorant, and sedative drug. Although the species of Radix Astragali have been defined as Astragalus membranaceus and A. membranaceus var. mongholicus in Pharmacopoeia of China, their taxonomy remains controversial. The phylogenetic relationships among 10 Astragalus taxa, which are commonly found in China including A. membranaceus, A. membranaceus var. mongholicus, Astragalus propinquus, Astragalus lepsensis, Astragalus aksuensis, Astragalus hoantchy, Astragalus hoantchy subsp. dshimensis, Astragalus lehmannianus, Astragalus sieversianus, and Astragalus austrosibiricus, were determined using the DNA sequences of the 5S ribosomal RNA (5S rRNA) spacer, internal transcribed spacer region (ITS), and 18S rRNA coding region. The 5S rRNA spacer, ITS, and 18S rRNA, amplified by polymerase chain reaction from the isolated genomic DNAs, were seq...
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species identification of radix astragali huangqi by dna sequence of its 5s rrna spacer domain
Phytochemistry, 2000Co-Authors: Jinao Duan, Tina T X Dong, Karl Wah Keung TsimAbstract:Abstract About 300 species and varieties of Astragalus are identified in China, making the identification of the origin of a particular Astragalus species on the consumer market difficult. A molecular genetic approach was developed to identify various species of Astragalus . Although the 5S-rRNA coding sequence is conserved in higher eukaryotes, the spacer domain of the 5S-rRNA gene has great diversity among different species. The 5S-rRNA spacer domain was amplified by polymerase chain reaction (PCR) from the isolated genomic DNA, and the PCR products (∼300 bp) covering the 5S-rRNA spacer domain were sequenced. The nucleotide sequences of Astragalus membranaceus , A. membranaceus var. mongholicus , A. lehmannianus , A. hoantchy , and of one closely related species Hedysarum polybotrys (Hongqi), were determined. Diversity in DNA sequence and restriction enzyme mapping among various species was found in their 5S-rRNA spacer domains. This is the first report on the detection of 5S-rRNA spacer region sequence of Astragalus , and the results could be used for genetic identification of Huangqi.
Michael J Donoghue - One of the best experts on this subject based on the ideXlab platform.
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monophyly of aneuploid Astragalus fabaceae evidence from nuclear ribosomal dna internal transcribed spacer sequences
American Journal of Botany, 1993Co-Authors: Martin F Wojciechowski, Michael J Sanderson, Bruce G Baldwin, Michael J DonoghueAbstract:Evolutionary relationships within Astragalus L. (Fabaceae) were inferred from nucleotide sequence variation in nuclear ribosomal DNA of both New World and Old World species. The internal transcribed spacer regions (ITS) of 1 8S-26S nuclear ribosomal DNA from representatives of 26 species of Astragalus, three species of Oxytropis DC., and two outgroup taxa were analyzed by polymerase chain reaction amplification and direct DNA sequencing. The length of the ITS 1 region within these taxa varied from 221 to 231 bp, while ITS 2 varied in length from 207 to 217 bp. Of the aligned, unambiguous positions, approximately 34% were variable in each spacer region. In pairwise comparisons among Astragalus species and outgroup taxa, sequence divergence at these sites ranged from 0 to 18.8% in ITS 1 and from 0 to 21.7% in ITS 2. Parsimony analyses of these sequences resulted in a well-resolved phylogeny that is highly concordant with previous cytogenetic and chloroplast DNA evidence for a major phylogenetic division in the genus. These data suggest that the New World aneuploid species of Astragalus form a monophyletic but morphologically cryptic group derived from euploid species of Old World (Eurasian) origin, which are consequently paraphyletic.
Tina T X Dong - One of the best experts on this subject based on the ideXlab platform.
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phylogeny of Astragalus in china molecular evidence from the dna sequences of 5s rrna spacer its and 18s rrna
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Tina T X Dong, Clarles Clarke, Zong H Song, Zhaoning Ji, Chunkeung Lo, Karl Wah Keung TsimAbstract:Radix Astragali (root of Astragalus; Huangqi) is a traditional Chinese medicine commonly used as an immunostimulant, hepatoprotective, diuretic, antidiabetic, analgesic, expectorant, and sedative drug. Although the species of Radix Astragali have been defined as Astragalus membranaceus and A. membranaceus var. mongholicus in Pharmacopoeia of China, their taxonomy remains controversial. The phylogenetic relationships among 10 Astragalus taxa, which are commonly found in China including A. membranaceus, A. membranaceus var. mongholicus, Astragalus propinquus, Astragalus lepsensis, Astragalus aksuensis, Astragalus hoantchy, Astragalus hoantchy subsp. dshimensis, Astragalus lehmannianus, Astragalus sieversianus, and Astragalus austrosibiricus, were determined using the DNA sequences of the 5S ribosomal RNA (5S rRNA) spacer, internal transcribed spacer region (ITS), and 18S rRNA coding region. The 5S rRNA spacer, ITS, and 18S rRNA, amplified by polymerase chain reaction from the isolated genomic DNAs, were seq...
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species identification of radix astragali huangqi by dna sequence of its 5s rrna spacer domain
Phytochemistry, 2000Co-Authors: Jinao Duan, Tina T X Dong, Karl Wah Keung TsimAbstract:Abstract About 300 species and varieties of Astragalus are identified in China, making the identification of the origin of a particular Astragalus species on the consumer market difficult. A molecular genetic approach was developed to identify various species of Astragalus . Although the 5S-rRNA coding sequence is conserved in higher eukaryotes, the spacer domain of the 5S-rRNA gene has great diversity among different species. The 5S-rRNA spacer domain was amplified by polymerase chain reaction (PCR) from the isolated genomic DNA, and the PCR products (∼300 bp) covering the 5S-rRNA spacer domain were sequenced. The nucleotide sequences of Astragalus membranaceus , A. membranaceus var. mongholicus , A. lehmannianus , A. hoantchy , and of one closely related species Hedysarum polybotrys (Hongqi), were determined. Diversity in DNA sequence and restriction enzyme mapping among various species was found in their 5S-rRNA spacer domains. This is the first report on the detection of 5S-rRNA spacer region sequence of Astragalus , and the results could be used for genetic identification of Huangqi.
Martin F Wojciechowski - One of the best experts on this subject based on the ideXlab platform.
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evidence on the monophyly of Astragalus fabaceae and its major subgroups based on nuclear ribosomal dna its and chloroplast dna trnl intron data
Systematic Botany, 1999Co-Authors: Martin F Wojciechowski, Michael J Sanderson, Jerming HuAbstract:Phylogenetic relationships among 115 species representing the legume genus Astragalus and 12 related genera were inferred from an analysis of nucleotide sequence variation in the internal transcribed spacers and 5.8S gene of nuclear ribosomal DNA. For a subset of these taxa, the ITS data were supplemented by sequences from the chloroplast trnL intron. Phylogenies derived from maximum parsimony and neighbor- joining analyses of sequence and insertion/ deletion characters all suggest that the vast majority of Astragalus is monophyletic (with the exception of "outlier" species). All New World Astragalus species with aneuploid chromosome numbers (n = 11-15) form a monophyletic group ("Neo-Astragalus"), which now includes the Mediterranean aneuploid Astragalus echinatus. Other Old World aneuploid species are not closely related to Neo-Astragalus, but rather are found among Old World euploid (n = 8, 16) groups. Similarly, the relatively few North American species with euploid numbers are not the closest relatives to Neo-Astragalus but are dispersed among divergent Old World groups that include both aneuploid and euploid species. The histor- ically allied genus Oxytropis is not nested within Astragalus, but forms a separate clade within the larger "Astragalean" clade. The proposed segregate genera Astracantha (Eurasian) and Orophaca (North American) are clearly nested within Astragalus s. str. South American species of Astragalus are nested within Neo- Astragalus and comprise at least two independently derived clades (along with their close North American relatives), as previously suggested by morphology. Parsimony reconstructions of characters that have been used in the traditional subgeneric taxonomy of the genus were examined and show high levels of homoplasy. Preliminary estimates of the absolute rate of species diversification in Astragalus suggest it may be higher than in some other, often cited, continental or insular adaptive radiations in angiosperms.
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monophyly of aneuploid Astragalus fabaceae evidence from nuclear ribosomal dna internal transcribed spacer sequences
American Journal of Botany, 1993Co-Authors: Martin F Wojciechowski, Michael J Sanderson, Bruce G Baldwin, Michael J DonoghueAbstract:Evolutionary relationships within Astragalus L. (Fabaceae) were inferred from nucleotide sequence variation in nuclear ribosomal DNA of both New World and Old World species. The internal transcribed spacer regions (ITS) of 1 8S-26S nuclear ribosomal DNA from representatives of 26 species of Astragalus, three species of Oxytropis DC., and two outgroup taxa were analyzed by polymerase chain reaction amplification and direct DNA sequencing. The length of the ITS 1 region within these taxa varied from 221 to 231 bp, while ITS 2 varied in length from 207 to 217 bp. Of the aligned, unambiguous positions, approximately 34% were variable in each spacer region. In pairwise comparisons among Astragalus species and outgroup taxa, sequence divergence at these sites ranged from 0 to 18.8% in ITS 1 and from 0 to 21.7% in ITS 2. Parsimony analyses of these sequences resulted in a well-resolved phylogeny that is highly concordant with previous cytogenetic and chloroplast DNA evidence for a major phylogenetic division in the genus. These data suggest that the New World aneuploid species of Astragalus form a monophyletic but morphologically cryptic group derived from euploid species of Old World (Eurasian) origin, which are consequently paraphyletic.
Galina Jeney - One of the best experts on this subject based on the ideXlab platform.
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chinese herbs Astragalus radix and ganoderma lucidum enhance immune response of carp cyprinus carpio and protection against aeromonas hydrophila
Fish & Shellfish Immunology, 2009Co-Authors: Laszlo Ardo, Kim D Thompson, Zsigmond Jeney, Alexandra Adams, Galina JeneyAbstract:Abstract The effect of Chinese herbs (Astragalus radix and Ganoderma lucidum) on immune response of carp was investigated. Fish were fed diets containing Astragalus (0.5%), Ganoderma (0.5%) and combination of two herbs (Astragalus 0.5% and Ganoderma 0.5%) for 5 weeks. Other groups of fish were vaccinated (i.p.) against Aeromonas hydrophila/Aeromonas salmonicida (Shering Plough, Essex, U.K.) at the beginning of the experiment and fed the same diets as described above. Control fish (negative control) and fish vaccinated only (positive control) were fed basal diets without supplements of herbs. The respiratory burst activity, phagocytosis, lysozyme activity and circulatory antibody titres in plasma were monitored. Following 5 weeks after feeding, fish were infected with A. hydrophila and mortalities were recorded. The results of this study showed that feeding non-vaccinated and vaccinated carp with combination of Astragalus and Ganoderma stimulated respiratory burst activity, phagocytosis of phagocytic cells in blood and lysozyme and circulatory antibody titres in plasma in vaccinated carp. Fish challenged with A. hydrophila had variable survival. The best survival (60%) was in vaccinated group fed with both herbs, while almost 90% of control fish (negative control) and 60% of fish vaccinated only (positive control) died.
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effect of two chinese herbs Astragalus radix and scutellaria radix on non specific immune response of tilapia oreochromis niloticus
Aquaculture, 2006Co-Authors: Galina Jeney, Timea Racz, Pao Xu, Zsigmond JeneyAbstract:The effect of two Chinese herbs (Astragalus radix and Scutellaria radix) on non-specific immune response of tilapia, Oreochromis niloticus, was investigated. Three-month-old tilapia with an average initial weight of 62.8 ± 5.40 g were fed diets containing four doses of Astragalus radix (0; 0.1; 0.5 and 1.0%) and four doses of Scutellaria radix (0; 0.1; 0.5 and 1.0%) for 4 weeks. Respiratory burst activity (extracellular superoxide anion production), phagocytosis by isolated blood leukocytes (neutrophils and monocytes) and lysozyme activity in plasma were investigated 1, 2, 3 and 4 weeks after feeding. Both Astragalus radix and Scutellaria radix can modulate the innate immune system of tilapia. The results of this study showed that feeding tilapia with 0.1 and 0.5% Astragalus radix for 1 week enhanced lysozyme activity and for 3 weeks stimulated phagocytosis by phagocytic blood cells, however, respiratory burst activity of phagocytic cells was not increased. On the other hand, inhibition of phagocytosis and respiratory burst activity was found when tilapia was fed with medium and high doses of Scutellaria radix, but not lysozyme activity. There were no significant differences among groups fed with different doses of both herbs. The optimal doses of Astragalus were 0.1% and 0.5% with an optimal feeding period of 3 weeks. Further work is needed to establish the stimulatory dose and optimal time of feeding of Scutellaria.
