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Robert G Chapman - One of the best experts on this subject based on the ideXlab platform.
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an effective identification and quantification method for ginkgo biloba flavonol glycosides with targeted evaluation of adulterated products
Phytomedicine, 2016Co-Authors: Ana Mani, Jaclyn Thomson, Flavie Peudru, Junzeng Zhang, Sarah Chen, Robert G ChapmanAbstract:Abstract Background Ginkgo biloba L. (Ginkgoaceae) leaf extract is one of the most popular herbal products on the market, as it contains flavone glycosides (≥ 24%) and terpene lactones (≥ 6%), which are proposed to have significant physiological effects. Unfortunately, the challenging financial climate has resulted in a natural health product market containing adulterated ginkgo products. Purpose 42 ginkgo samples were analyzed to establish an HPLC profile for authentic ginkgo and common ginkgo adulterants, and to develop a method capable of easily detecting adulteration in ginkgo commercial products. Method In this study an efficient and targeted HPLC analysis method was established that is capable of distinguishing flavonol glycosides and aglycones simultaneously for the evaluation of ginkgo powdered extracts (PEs) and finished products in a single, 13 min run. Thirteen ginkgo leaf samples, fifteen standardized powdered extracts, and fourteen commercially available ginkgo products have been analyzed using this new HPLC method. Chromatograms were compared to six standard reference materials: one flavonol glycoside (rutin), three aglycones (quercetin, kaempferol and isorhamnetin), and two isoflavones (genestin and genistein). The quantitative chromatographic data was interpreted by principal component analysis (PCA), which assisted in the detection of unexpected chromatographic features in various adulterated botanical products. Results Only three of the commercially available ginkgo finished products tested in this study were determined to be authentic, with flavonol glycoside rutin, and aglycones quercetin, kaempferol, and isorhamnetin found to be common adulterants in the ginkgo powdered extract and finished product samples. Conclusion Despite evidence of adulteration in most of the samples, each of the samples discussed herein met most of the current pharmacopeial standards. It is therefore critical that a preliminary evaluation be utilized to detect adulteration in commercial ginkgo products, prior to the acid hydrolysis procedure utilized in the current testing methods.
Michael L Christianson - One of the best experts on this subject based on the ideXlab platform.
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differences in the scaling of area and mass of ginkgo biloba Ginkgoaceae leaves and their relevance to the study of specific leaf area
American Journal of Botany, 2011Co-Authors: Karl J Niklas, Michael L ChristiansonAbstract: Premise of the study: The manner in which the area of the leaf lamina ( A ) scales with respect to the dry mass of the lamina ( M ) is an important functional trait that is correlated with whole-plant growth rates and habitat preferences across diverse species. However, the extent to which the scaling between these two variables differs among leaves collected from different types of shoots within the canopy of a tree is poorly understood. Should they exist, signifi cant differences in the A vs. M scaling relationship within canopies would raise a number of important questions, in particular what constitutes an adequate sampling procedure to determine the whole-canopy A vs. M relationship. Methods: To address this issue, we used a large data set representing 13 biologically distinct categories of leaves sampled from mega- and microsporangiate trees of the dioecious gymnosperm Ginkgo biloba . Key results: Analyses of the data for these 13 categories of leaves identify seven statistically signifi cantly different modes of A vs. M scaling that result in signifi cant differences in how specifi c leaf area (SLA) changes as M varies within the canopies of Ginkgo . Conclusions : These results indicate that the protocols used to sample leaves for the analysis of foliar functional traits such as specifi c leaf area need to acknowledge and cope with the effects of leaf and shoot polymorphisms on the quantifi cation of functional traits (and on the construction and testing of hypotheses about these traits).
Cheng Quan - One of the best experts on this subject based on the ideXlab platform.
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a new tertiary ginkgo Ginkgoaceae from the wuyun formation of jiayin heilongjiang northeastern china and its paleoenvironmental implications
American Journal of Botany, 2010Co-Authors: Cheng Quan, Zhiyan 周志炎 ZhouAbstract:The living fossil Ginkgo, a relict of a once dominant gymnosperm, existed and flourished early in the Mesozoic, but only a vague outline of its evolutionary history in the Tertiary has been unveiled. Here we describe a new species, Ginkgo jiayinensis sp. nov., from the Wuyun Formation of Jiayin, China, which is another well-established Tertiary species based on leaf fossils besides G. adiantoides. The most remarkable feature of the new species is the amphistomatic leaves, likely representing a distinct evolutionary line of the genus in this time interval. Ginkgo jiayinensis is similar to the co-occurring G. adiantoides and extant G. biloba in the lower cuticle, but the two latter species clearly differ in having hypostomatic leaves. Ginkgo biloba is used as the nearest living equivalent (NLE) species for both G. adiantoides and G. jiayinensis in reconstructing paleo-CO(2), as it has been used for other fossil species with either hypostomatic or amphistomatic leaves. The two Tertiary species are almost identical in stomatal index in abaxial cuticles (8.4 and 8.5, respectively), showing no strong differences in response to atmospheric CO(2). Amphistomatic G. jiayinensis would therefore have used a different ecological strategy from that of G. adiantoides of the same bed.
Gaetan Guignard - One of the best experts on this subject based on the ideXlab platform.
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insights into the leaf cuticle fine structure of ginkgoites skottsbergii lundblad from the albian of patagonia and its relationship within Ginkgoaceae
Review of Palaeobotany and Palynology, 2016Co-Authors: Gaetan Guignard, Georgina M Del Fueyo, Liliana Villar De Seoane, Martin A Carrizo, Maiten Lafuente A DiazAbstract:New specimens of Ginkgoites skottsbergii Lundblad collected from the Albian Kachaike Formation at the type locality in Santa Cruz Province, Argentina are characterized with additional scanning and transmission electron microscopic observations and EDS elemental analysis. The micromorphology of the amphistomatic and 12-segmented leaf of G. skottsbergii shows a smooth lamina with straight and pitted anticlinal and slightly granulate periclinal walls, abundant epicuticular wax on the petiole surface, and monocyclic to partially dicyclic stomatal apparatuses with between six and eight papillate to non-papillate, finely striated subsidiary cells and guard cells with smooth walls. Palaeoenvironmental considerations suggest that G. skottsbergii was a mesophytic plant. The TEM studies of ordinary epidermal cell cuticles and subsidiary and guard cell cuticles reveal the general ultrastructural features of Ginkgoaceae. Using confidence intervals based on 30 statistical measurements and the Mann–Whitney test for five measurements of EDS ratios of the elements, 33 ultrastructural characters were identified that enabled discussion at different taxonomic levels. Comparisons with the previously studied Ginkgoites ticoensis Archangelsky reveal that 14 of these characteristics could be species features that reinforce the identity of G. skottsbergii, and 19 could be genus features. EDS analysis and comparisons with G. ticoensis yielded five ratios using Cl, N, K, S, and Ca, revealing seven ratios of potential species interest and eight ratios at the genus level among the three zones evaluated in the leaf cuticle of each species. A three-dimensional reconstruction of the cuticle and an ultrastructural identification key for each of the three types of cuticle are also provided, i.e., from the ordinary epidermal cell and the subsidiary and guard cells of the stomatal apparatus. Fruitful statistical comparisons with two previously studied ginkgos allow discussion of the relationships within the Ginkgoaceae with respect to 18 features, six of them being potentially significant at the genus level and four at the family level.
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Leaf Cuticle Anatomy and the Ultrastructure of Ginkgoites ticoensis Archang. from the Aptian of Patagonia
International Journal of Plant Sciences, 2013Co-Authors: Georgina M Del Fueyo, Gaetan Guignard, Liliana Villar De Seoane, Sergio ArchangelskyAbstract:The leaf cuticle of the Ginkgoites ticoensis Archang. type material from the Aptian Anfiteatro de Tico Formation in Patagonia, Argentina, is fully characterized with additional scanning and transmission electron microscopic observations. Many new anatomical and ultrastructural cuticular features are identified in the four-lobed leaf of G. ticoensis: the leaf shows a hypostomatic and papillate laminae, straight and pitted anticlinal and granulate periclinal walls, actinocytic stomata with between five and seven papillate, striate subsidiary cells, and guard cells with anticlinal smooth walls. The TEM studies on ordinary epidermal cells, papillae, subsidiary cells, and guard cells reveal general ultrastructural features of Ginkgoaceae: an outer polylamellate layer A made with A1 and a granular inner layer A2; A1 with an upper part A1U with continuous and straight translucent lamellae; a lower part A1L with significantly disrupted and waving translucent lamellae; and the fibrillar cuticular layer B1 as the i...
Chengxin Fu - One of the best experts on this subject based on the ideXlab platform.
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development of the first chloroplast microsatellite loci in ginkgo biloba Ginkgoaceae
Applications in Plant Sciences, 2013Co-Authors: Mingshui Zhao, Chengxin Fu, Yunpeng ZhaoAbstract:Premise of the study: To investigate population genetics, phylogeography, and cultivar origin of Ginkgo biloba, chloroplast microsatellite primers were developed. Methods and Results: Twenty-one chloroplast microsatellite markers were identified referring to the two published chloroplast genomes of G. biloba. Polymorphisms were assessed on four natural populations from the two refugia in China. Eight loci were detected to be polymorphic in these populations. The number of alleles per locus ranged from three to seven, and the unbiased haploid diversity per locus varied from 0.441 to 0.807. Conclusions: For the first time, we developed 21 chloroplast microsatellite markers for G. biloba, including 13 monomorphic and eight polymorphic ones within the assessed natural populations. These markers should provide a powerful tool for the study of genetic variation of both natural and cultivated populations of G. biloba, as well as cultivars.
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eleven novel microsatellite markers developed from the living fossil ginkgo biloba Ginkgoaceae
Conservation Genetics, 2009Co-Authors: Yeye Chen, Bicai Guan, Chengxin FuAbstract:Ginkgo biloba L. (Ginkgoaceae), a famous and widely cultivated plant, is often referred to as a living fossil. Here we isolated and characterized 11 polymorphic microsatellite loci from G. biloba using a modified biotin-capture method. These loci showed high levels of allelic diversity, alleles sizes ranged from 4 to 16 per locus with polymorphism information content ranging from 0.432 to 0.909 (average = 0.752). The observed and expected heterozygosities ranged from 0.208 to 0.708 (average = 0.484) and from 0.501 to 0.934 (average = 0.795), respectively. These microsatellite markers can be used as genetic markers for further studies on genetic diversity, genetic structure and the gene flow among populations of this species.
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phylogeography of a living fossil pleistocene glaciations forced ginkgo biloba l Ginkgoaceae into two refuge areas in china with limited subsequent postglacial expansion
Molecular Phylogenetics and Evolution, 2008Co-Authors: Wei Gong, Chengxin Fu, Chuan Chen, Christoph Dobes, Marcus A KochAbstract:Ginkgo biloba is one of the most famous and therefore intensively studied living fossils. The Ginkgoaceae was suggested to have originated in the early Permian approximately 280 mya, and at the height of their worldwide radiation consisted of least 16 genera that were distributed in temperate forests. However, China's G. biloba is the only species of this genus which has survived until today. Using a phylogeograph- ical approach we analyzed the history of this remnant from the past. G. biloba is native to China and has been distributed less than 300 years ago by humans throughout all temperate regions of the world. Sep- arate from this human influence, native Chinese populations of G. biloba have been affected by the cycles of glaciation and deglaciation of the Pleistocene era, similar to many other global plant species. We used molecular markers from the nuclear (AFLPs) and plastid genomes (trnK intron, trnS-trnG intergenic spacer), and based on these data, glacial survival of Gingko populations within two refugia in Southwest- ern and Eastern China, respectively, is suggested. Specifically, for the first time, this study provides evi- dence of the existence of a refuge area in Eastern China on the West Tianmu Mountains. We can not support any extensive postglacial range expansion from these refuge areas. Furthermore, AFLP data indi- cate substantial genetic differentiation among populations from Southwestern, Eastern and Central China. We also hypothesize that this evidence supports that as a long-lived dioecious plant, G. biloba dis- plays high levels of intra-populational genetic diversity that have been maintained in most populations, regardless if they are native or reforested stands. Furthermore, we provide evidence that planted trees from Europe, Japan, Korea and America were introduced multiple times from Eastern China.
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assessing genetic diversity of ginkgo biloba l Ginkgoaceae populations from china by rapd markers
Biochemical Genetics, 2004Co-Authors: Lang Shen, Xin Zhang, Xiaoyong Chen, Chengxin FuAbstract:Genetic diversity and differentiation of nine populations of Ginkgo biloba L. (Ginkgoaceae) from China were evaluated using RAPD. Of 47 clear and repeatable RAPD bands, 46 were polymorphic (overall polymorphism = 97.9%). A ranged from 1.57 to 1.83 with a mean of 1.75. Mean H e was 0.3159 (0.2429–0.3603). The Shannon index ranged from 0.3432 to 0.5119 with a mean of 0.4489. The G ST was 0.1609 and AMOVA analysis indicated 89% of the variation within populations. UPGMA clustered the 9 populations into two groups: one containing only population JF and the other including 8 populations. Genetic diversity and differentiation of Chinese populations were higher than those of Korean and North American populations, which are ultimately descended from China, as reported previously.