Magnolia sinica is one of the most threatened trees endemic to Southeast Yunnan.Based on our investigations,only 52 individuals and eight populations are found in the wild.M.sinica has been categorized as Critically E...Magnolia sinica is one of the most threatened trees endemic to Southeast Yunnan.Based on our investigations,only 52 individuals and eight populations are found in the wild.M.sinica has been categorized as Critically Endangered on the IUCN Red List and identified as a "Plant Species with Extremely Small Populations(PSESP)".Its fruit/seed set is very low and seedlings are rarely found in the wild.It is hypothesized that it may encounter obstacles to reproductive success.This study,therefore,focuses on its reproductive biology,knowledge of which is essential for effective conservation.Flowers of this species are protogynous and nocturnal,and possess a two-day rhythm of sexual presentation.For the first night of anthesis,the flowers are in the pistillate stage during which tepals open at dusk and close approx.1 h later(except for the open outer ones).They remain closed until the next afternoon,when flowers,now in the staminate stage,re-open and remain so until the tepals drop.Nocturnal beetles enter into the flowers and remain trapped throughout the night as the flower closes,during which time they feed on tepals.Pollen-gathering bees are found to visit the re-opened flowers and the beetles are released during this stage.Two species of Pleocomidae and Curculionidae beetles appear to be effective pollinators.M.sinica is a self-compatible,pollinator-dependent species,and its fruit/seed set can be significantly increased by hand-pollination.No functional seed dispersers have been found in its extant natural habitats.These findings suggest that it may face both pollination and seed disperser insufficiencies in its current fragmented habitats,which may account for its low regeneration.Here we propose conservation strategies based on our findings.展开更多
A new tetrastilbene named carasinol D （1） was isolated from the roots of Caragana sinica. Its structure was elucidated by spectroscopic analysis. Compound 1 was obtained from carasinol B （2） by an acid-catalyzed c...A new tetrastilbene named carasinol D （1） was isolated from the roots of Caragana sinica. Its structure was elucidated by spectroscopic analysis. Compound 1 was obtained from carasinol B （2） by an acid-catalyzed conversion.展开更多
Distribution and abundance of Pseudeuphausia sinica off the Changjiang River Estuary （30 ° 00′ – 32 ° 00′ N, 122 ° 00′ –123 ° 30 ′E）, the East China Sea were studied in relation to environm...Distribution and abundance of Pseudeuphausia sinica off the Changjiang River Estuary （30 ° 00′ – 32 ° 00′ N, 122 ° 00′ –123 ° 30 ′E）, the East China Sea were studied in relation to environmental features associated with the regional warming. P. sinica is a subtropical species. Off the Changjiang River Estuary, its abundance reached maximum in summer. To examine spatial and temporal changes of P. sinica off the Changjiang River Estuary, the authors have combined all available sampling data in 1979, 1981, and 2000–2007. This database shows that a significant increase in abundances of P. sinica was observed in spring of 2000–2007 as compared with 1979, 1981. The abundance of P. sinica increased from 0.18–0.21 ind./m 3 in 1979 and 1981 to 0.68–4.00 ind./m 3 in 2000–2007. Accordingly, the sea temperature increased obviously from spring of 1979, 1981 to the 2000s. The authors further found a positive relationship between average surface temperature and average abundance of P. sinica. Regional warming, together with the release of predator induced stress due to a sharp decline in the abundance of its predator （e.g., fishes）, were thought to be responsible for the increase in abundance of P. sinica in water off the Changjiang River Estuary.展开更多
The objectives of this study were to investigate the effects of successive continuous generation （SCG） cuttings of Buxus sinica var. parvifolia on the rejuvenation of ortets at the hormone level, detect levels of in...The objectives of this study were to investigate the effects of successive continuous generation （SCG） cuttings of Buxus sinica var. parvifolia on the rejuvenation of ortets at the hormone level, detect levels of indoleacetic acid （IAA）, abscisic acid （ABA）, isopentenyladenosine （iPA）, zeatin riboside （ZR） and gibberellin4 （GA4） during the rooting process of different generations by means of enzyme-linked immunosorbent assay （ELISA） technology and statistically analyze the rooting characteristics of cuttings. The results show that, the root systems of subsequent generations （generation 1998, 2000） developed satisfactorily, only a few initial generation （generation 1990, 1994） cuttings rooted and the root growth was inhibited. Around the period of callus formation and root projection through the epidermis, there was a marked, regular variation in the levels of IAA, ABA and GA4 between the initial generations and subsequent generations.展开更多
In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were c...In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(FT-IR) and 1D and 2D Nuclear Magnetic Resonance(NMR).FT-IR spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon.展开更多
Yang Tian et al.（2017）recognize bed-load-dominated and suspended-load-dominated hyperpycnites in the Beilaishi section,but we maintain that only Fig.1b is well consistent with their descriptions.The interface existi...Yang Tian et al.（2017）recognize bed-load-dominated and suspended-load-dominated hyperpycnites in the Beilaishi section,but we maintain that only Fig.1b is well consistent with their descriptions.The interface existing in the lower part separates it into two thin-bedded grading deposits then with climbing ripples in Fig.展开更多
Two new minor constituents,musinisins A(1)and B(2),together with five known compounds(3-7),were isolated from the aerial parts of Munronia sinica.Their structures were established by means of spectroscopic methods and...Two new minor constituents,musinisins A(1)and B(2),together with five known compounds(3-7),were isolated from the aerial parts of Munronia sinica.Their structures were established by means of spectroscopic methods and the absolute stereochemistry of 1 was determined by single crystal X-ray experiment.Compound 4 showed antiangiogenic activity evaluated by a zebrafish model and apoptosis-inducing effect on A549 lung cancer cells.展开更多
A new flavonol glycoside, 5,7,3,4 tetrahydroxy 3 methoxyflavonol 3 O β D glucopyranoside(1) was isolated along with quercetin(2), quercetin 3 O α L rhamnopyranoside(3), quercetin 3 O β D ...A new flavonol glycoside, 5,7,3,4 tetrahydroxy 3 methoxyflavonol 3 O β D glucopyranoside(1) was isolated along with quercetin(2), quercetin 3 O α L rhamnopyranoside(3), quercetin 3 O β D glucopyranoside(4) and kaempferol 3 O β D (6' O p coumaroyl) glucopyranoside(5) from Anaphalis sinica Hance. Their structures were determined on the basis of spectral data(MS, UV, IR, 1H and 13 C NMR). The structure of compound 1 was confirmed by X ray crystallographic analysis.展开更多
Two polysaccharides (ESP-A1 and ESP-A2) were isolated from the cold water extract of Ephedra sinica Stapf and purified through ethanol precipitation, deproteinization and by ion exchange and gel-filtration chromatogra...Two polysaccharides (ESP-A1 and ESP-A2) were isolated from the cold water extract of Ephedra sinica Stapf and purified through ethanol precipitation, deproteinization and by ion exchange and gel-filtration chromatography. Their molecular weight was determined using high performance size exclusion chromatog-raphy and evaporative light scattering detector (HPSEC-ELSD) and their monosaccharide composition was analyzed by high performance capillary electrophoresis (HPCE) based on pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). It was shown that ESP-A1 consisted of xylose, arabinose, glucose, mannose and galactose and ESP-A2 consisted of xylose, arabinose, rhamnose and galactose, in a molar ratio (%) of 3.2: 61.1: 11.1: 12.9: 11.6 and 20.6: 67.7: 5.0: 6.7, respectively. The molecular weights (Mw) of ESP-A1 and ESP-A2 were 5.83 × 104 Da and more than 200 × 104 Da, respectively. To the best of our knowledge, two neutral polysaccharides are now being reported for the first time in this study.展开更多
基金supported financially by the NSFC-Yunnan joint fund to support key projects to W.B.Sun(Grant no.U1302262)the Young Academic and Technical Leader Raising Foundation of Yunnan Province to G.Chen(2015HB091)
文摘Magnolia sinica is one of the most threatened trees endemic to Southeast Yunnan.Based on our investigations,only 52 individuals and eight populations are found in the wild.M.sinica has been categorized as Critically Endangered on the IUCN Red List and identified as a "Plant Species with Extremely Small Populations(PSESP)".Its fruit/seed set is very low and seedlings are rarely found in the wild.It is hypothesized that it may encounter obstacles to reproductive success.This study,therefore,focuses on its reproductive biology,knowledge of which is essential for effective conservation.Flowers of this species are protogynous and nocturnal,and possess a two-day rhythm of sexual presentation.For the first night of anthesis,the flowers are in the pistillate stage during which tepals open at dusk and close approx.1 h later(except for the open outer ones).They remain closed until the next afternoon,when flowers,now in the staminate stage,re-open and remain so until the tepals drop.Nocturnal beetles enter into the flowers and remain trapped throughout the night as the flower closes,during which time they feed on tepals.Pollen-gathering bees are found to visit the re-opened flowers and the beetles are released during this stage.Two species of Pleocomidae and Curculionidae beetles appear to be effective pollinators.M.sinica is a self-compatible,pollinator-dependent species,and its fruit/seed set can be significantly increased by hand-pollination.No functional seed dispersers have been found in its extant natural habitats.These findings suggest that it may face both pollination and seed disperser insufficiencies in its current fragmented habitats,which may account for its low regeneration.Here we propose conservation strategies based on our findings.
基金This project is supported by the National Natural Science Foundation of China （No. 39270800）；the Major Subject of the Science and Technology Commission of Shanghai Municipality （No. 06DZ19709）.
文摘A new tetrastilbene named carasinol D （1） was isolated from the roots of Caragana sinica. Its structure was elucidated by spectroscopic analysis. Compound 1 was obtained from carasinol B （2） by an acid-catalyzed conversion.
基金The National Key Program for Fundamental Research and Development(973 Project)under contract No.2010CB428705the Special Research Fund for the National Non-profit Institutes under contract No.2009T04the Major Research Plan of the National Natural Science Foundation of China under contract No.90511005
文摘Distribution and abundance of Pseudeuphausia sinica off the Changjiang River Estuary （30 ° 00′ – 32 ° 00′ N, 122 ° 00′ –123 ° 30 ′E）, the East China Sea were studied in relation to environmental features associated with the regional warming. P. sinica is a subtropical species. Off the Changjiang River Estuary, its abundance reached maximum in summer. To examine spatial and temporal changes of P. sinica off the Changjiang River Estuary, the authors have combined all available sampling data in 1979, 1981, and 2000–2007. This database shows that a significant increase in abundances of P. sinica was observed in spring of 2000–2007 as compared with 1979, 1981. The abundance of P. sinica increased from 0.18–0.21 ind./m 3 in 1979 and 1981 to 0.68–4.00 ind./m 3 in 2000–2007. Accordingly, the sea temperature increased obviously from spring of 1979, 1981 to the 2000s. The authors further found a positive relationship between average surface temperature and average abundance of P. sinica. Regional warming, together with the release of predator induced stress due to a sharp decline in the abundance of its predator （e.g., fishes）, were thought to be responsible for the increase in abundance of P. sinica in water off the Changjiang River Estuary.
基金the National Natural Science Foundation of China （Grant No. 30070633）.
文摘The objectives of this study were to investigate the effects of successive continuous generation （SCG） cuttings of Buxus sinica var. parvifolia on the rejuvenation of ortets at the hormone level, detect levels of indoleacetic acid （IAA）, abscisic acid （ABA）, isopentenyladenosine （iPA）, zeatin riboside （ZR） and gibberellin4 （GA4） during the rooting process of different generations by means of enzyme-linked immunosorbent assay （ELISA） technology and statistically analyze the rooting characteristics of cuttings. The results show that, the root systems of subsequent generations （generation 1998, 2000） developed satisfactorily, only a few initial generation （generation 1990, 1994） cuttings rooted and the root growth was inhibited. Around the period of callus formation and root projection through the epidermis, there was a marked, regular variation in the levels of IAA, ABA and GA4 between the initial generations and subsequent generations.
基金Major State Basic Research Projects of China(973-2010CB732204)Specific Programs in Graduate Science and Technology Innovation of Beijing Forestry University(BLYJ201110)
文摘In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(FT-IR) and 1D and 2D Nuclear Magnetic Resonance(NMR).FT-IR spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon.
文摘Yang Tian et al.（2017）recognize bed-load-dominated and suspended-load-dominated hyperpycnites in the Beilaishi section,but we maintain that only Fig.1b is well consistent with their descriptions.The interface existing in the lower part separates it into two thin-bedded grading deposits then with climbing ripples in Fig.
基金supported financially by the Bureau of Science and Technology of Kunming City.
文摘Two new minor constituents,musinisins A(1)and B(2),together with five known compounds(3-7),were isolated from the aerial parts of Munronia sinica.Their structures were established by means of spectroscopic methods and the absolute stereochemistry of 1 was determined by single crystal X-ray experiment.Compound 4 showed antiangiogenic activity evaluated by a zebrafish model and apoptosis-inducing effect on A549 lung cancer cells.
文摘A new flavonol glycoside, 5,7,3,4 tetrahydroxy 3 methoxyflavonol 3 O β D glucopyranoside(1) was isolated along with quercetin(2), quercetin 3 O α L rhamnopyranoside(3), quercetin 3 O β D glucopyranoside(4) and kaempferol 3 O β D (6' O p coumaroyl) glucopyranoside(5) from Anaphalis sinica Hance. Their structures were determined on the basis of spectral data(MS, UV, IR, 1H and 13 C NMR). The structure of compound 1 was confirmed by X ray crystallographic analysis.
文摘Two polysaccharides (ESP-A1 and ESP-A2) were isolated from the cold water extract of Ephedra sinica Stapf and purified through ethanol precipitation, deproteinization and by ion exchange and gel-filtration chromatography. Their molecular weight was determined using high performance size exclusion chromatog-raphy and evaporative light scattering detector (HPSEC-ELSD) and their monosaccharide composition was analyzed by high performance capillary electrophoresis (HPCE) based on pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). It was shown that ESP-A1 consisted of xylose, arabinose, glucose, mannose and galactose and ESP-A2 consisted of xylose, arabinose, rhamnose and galactose, in a molar ratio (%) of 3.2: 61.1: 11.1: 12.9: 11.6 and 20.6: 67.7: 5.0: 6.7, respectively. The molecular weights (Mw) of ESP-A1 and ESP-A2 were 5.83 × 104 Da and more than 200 × 104 Da, respectively. To the best of our knowledge, two neutral polysaccharides are now being reported for the first time in this study.
