In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations an...In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations and extraction cycles were experimental factors.Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids.The optimal extraction parameters were solid/liquid ratio 1:50 g/mL,ultrasonic power 316 W,ethanol concentration 50%,4 extraction cycles.In the optimized condition,the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g.展开更多
We investigated the combined effects of soil moisture and light intensity on the growth, development and ecophysiological characteristics of one-year old Amorpha fruticosa seedlings. Soil moisture and light intensity ...We investigated the combined effects of soil moisture and light intensity on the growth, development and ecophysiological characteristics of one-year old Amorpha fruticosa seedlings. Soil moisture and light intensity influenced the ecophysiological characteristics of Amorpha fruticosa seedlings. Soil moisture resulted in the decreases of growth rate, individual size, net photosynthetic rate, transpiration rate, leaf water loss rate (WLR), and biomass accumulation of plant parts, and led to increased leaf water saturation deficit (WSD). Under water stress, more photosynthetic products were allocated to root growth. With decreasing light intensity, net photosynthetic rate, transpiration rate, chla/b, water saturation deficit, water use efficiency, water loss rate and biomass accumulation declined, while Chla, Chlb, Chla+b and carotenoids (Car) increased and more photosynthetic products were allocated to stem and leaf growth. Maximum growth vigor, net photosynthetic rate and total biomass accumulation in Amorpha fruticosa seedlings was recorded at 75 80% soil water-holding capacity and 100% light density in greenhouse environments.展开更多
Objective:To evaluate the protective effect of Woodfordia fruticosa Kurz flowers against experimentally induced liver toxicity in rats.Methods:Two different doses of methanol extract of Woodfordia fruticosa(WFM) were ...Objective:To evaluate the protective effect of Woodfordia fruticosa Kurz flowers against experimentally induced liver toxicity in rats.Methods:Two different doses of methanol extract of Woodfordia fruticosa(WFM) were evaluated for the hepatoprotective activity against diclofenac sodium induced hepatotoxicity in rats.Various biochemical parameters like alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP),total protein(TP),albumin(ALB),blood urea nitrogen(BUN) from serum;total protein(TP),glutathione (GSH) levels,catalase(CAT) and glutathione peroxidase(GPx) activities from liver were studied; histopathologic changes of liver were also evaluated.Results:WFM effectively reduced the elevated levels of serum ALT,AST,ALP and BUN,enhanced the reduced TP,ALB and hepatic GSH,CAT,GPx activity.The histopathological analysis suggested that WFM decreased the degree of liver fibrosis induced by diclofenac.Conclusions:This study demonstrates the hepatoprotective activity of WFM and thus scientifically support the use of this plant in traditional medicine for the treatment of liver disorders.展开更多
Dasiphora fruticosa comprises male,female and hermaphrodite plants,which are distributed sympatrically in some populations on the Qinghai-Tibet Plateau.To explore what governs the coexistence of these three sexual phe...Dasiphora fruticosa comprises male,female and hermaphrodite plants,which are distributed sympatrically in some populations on the Qinghai-Tibet Plateau.To explore what governs the coexistence of these three sexual phenotypes,we investigated the DNA contents,pollen and ovule production,pollen deposition,and performed hand-pollination in both hermaphroditic and dioecious individuals of D.fruticosa.Flow cytometry confirmed that the DNA content of males and females were almost twice as much as that of the hermaphrodites.Male and female flowers produced more pollen grains and ovules than hermaphroditic flowers.Hand-pollinated treatments showed that unisexual flowers were sterile in one sexual function and bisexual flowers were fertile for both functions,but no sterile seeds were produced between unisexual and bisexual flowers.Our findings imply that polyploidy is related to gender dimorphism,and both are likely to play a strong role in the coexistence of two cryptic biological species of D.fruticosa(low ploidy hermaphroditic species and high ploidy dioecious species)in the Qinghai-Tibet Plateau.展开更多
A new isoflavone was obstained from the medicinal herb Amorpha fruticosa. It was elucidated asbenzopyran- 12-one, 1,4,10,11 - tetrahydro-6′-[8′-(hydroxymethy1)etheny1]-2,3-dimethoxy-8′-O-β-glucopyranosy1-O-α-D-...A new isoflavone was obstained from the medicinal herb Amorpha fruticosa. It was elucidated asbenzopyran- 12-one, 1,4,10,11 - tetrahydro-6′-[8′-(hydroxymethy1)etheny1]-2,3-dimethoxy-8′-O-β-glucopyranosy1-O-α-D-arabinoside by spectroscopic methods including UV, IR, 1D NMR and 2D NMR techniques. And the activity against acetaminophen-induced hepatotoxicity of this compound was also studied, and found this compound can protect liver obviously from hepatotoxicity induced by acetaminophen (AAP). ?2009 Ting Guo Kang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
Objective:To investigate the role of water-soluble extract of Salvia fruticosa(Creek sage)(S.fruticosa) leaves in reducing both intrinsic cellular and H_2O_2-induced DNA oxidation in cultured human embryonic kidney 29...Objective:To investigate the role of water-soluble extract of Salvia fruticosa(Creek sage)(S.fruticosa) leaves in reducing both intrinsic cellular and H_2O_2-induced DNA oxidation in cultured human embryonic kidney 293 cells.S.fruiicosa.native to the Eastern-Mediterranean basin,is widely used as a medicinal herb for treatment of various diseases.Methods:Dried leaves of 5.fruticosa were extracted in phosphate buffer saline and purified using both vacuum and high pressure filtrations.Each mL of the preparation contained(7.1±1.0)mg of extract.HEK-293 cells were incubated in one set with S.fruticosa extract in the presence of 0.1 mmol/L H_2O_2,and in the other set with the addition of the extract alone.The DNA oxidation was measured using fluorescence upon fluorescein isothiocyanate derivarization of 8-oxoguanine moieties.The fluorescence was measured using flow cytometry technique.Results:Cells incubated 3 h with 150μL extract and exposed to 0.1 mmol/L H_2O_2 showed lower intensity of fluorescence,and thus lower DNA oxidation.Moreover,cells incubated 3 h with 100μl.of the extract showed lower intensity of fluorescence,and thus lower intrinsic cellular DNA oxidation compared to control(without S.fruticosa).Conchisions:The results from this study suggest that the water-soluble extract of S.fruticosa leaves protects against both H_2O_2-induced and intrinsic cellular DNA oxidation in human embryonic kidney 293 cells.展开更多
Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash crop.Kn...Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash crop.Knowledge about the impacts of maternal saline environment on seed attributes of this important euhalophyte is lacking.This study investigated the effects of maternal salinity on yield,size and stress tolerance of S.fruticosa seeds.Seedlings of S.fruticosa were grown in a green net house under increasing maternal salinity levels(0,300,600 and 900 mM NaCl)until seed production.Total yield,size,stress tolerance and germination of the descended seeds under different maternal saline conditions were examined.Plants grown under saline conditions(300,600 and 900 mM NaCl)produce a substantially higher quantity of seeds than plants grown under non-saline condition(0 mM NaCl).Low maternal salinity(300 mM NaCl)improves seed size.Seeds produced under all maternal salinity levels display a higher tolerance to low temperature(night/day thermoperiod of 10℃/20℃),whereas seeds produced under 300 mM NaCl maternal saline condition show a better tolerance to high temperature(night/day thermoperiod of 25℃/35℃)during germination.Seeds from all maternal saline conditions germinate better in the 12 h photoperiod(12 h light/12 h dark)than in the dark(24 h dark);however,seeds produced from low and moderate maternal saline conditions(300 and 600 mM NaCl)show a higher germination in the dark than those from control and high maternal saline conditions(0 and 900 mM NaCl).In general,maternal salinity is found to improve yield,size and stress tolerance of S.fruticosa seeds.展开更多
[Objectives]To study the effects of Fruticosa potentilla L.on the expression of key enzymes and hormones related to glucose and lipid metabolism in T2DM rats.[Methods]The ethyl acetate fraction of 95%methanol extract ...[Objectives]To study the effects of Fruticosa potentilla L.on the expression of key enzymes and hormones related to glucose and lipid metabolism in T2DM rats.[Methods]The ethyl acetate fraction of 95%methanol extract of F.potentilla(MEE)was administered orally to the T2DM rats,and the level of glucose and expression of insulin,resistin,leptin,glucokinase(GK)and glucose-6-phosphatase(G-6-Pase)in the rats were measured and detected.[Results]In the T2DM rats administered with MEE,the postprandial blood glucose level decreased,the expression levels of resistin,leptin and G-6-Pase were down-regulated,and the expression levels of insulin and GK were up-regulated(P<0.05,P<0.01).[Conclusions]F.potentilla can reduce effectively postprandial blood glucose level,regulate the expression of a variety of enzymes and hormones related to glucose and lipid metabolism and recover partially the insulin level in T2DM rats to achieve resistance to T2DM.展开更多
A method based on degenerate Oligo primed polymerase chain reaction (PCR) and random amplification of cDNA end (RACE) PCR for cloning a full length cDNA is described. An Amorpha fruticosa cDNA clone encoding UDP gluco...A method based on degenerate Oligo primed polymerase chain reaction (PCR) and random amplification of cDNA end (RACE) PCR for cloning a full length cDNA is described. An Amorpha fruticosa cDNA clone encoding UDP glucose pyrophosphorylase (UGP), a key enzyme producing UDP glucose in the synthesis of sucrose and cellulose, is cloned by using this method. We design 5’ RACE primers based on UGPA1 fragment, which obtains from degenerate PCR. Inverse PCR and nested PCR enable cloning of the remainder 5’ and 3’ end fragments of the gene. The deduced amino acid sequence exhibits significant homology with the other UGP genes cloned. This method is more simple and inexpensive than screening cDNA library, and can be easily adapted to clone other genes.展开更多
Aims Recent studies have shown that alpine meadows on the Qinghai-Tibetan plateau act as significant CO_(2)sinks.On the plateau,alpine shrub meadow is one of typical grassland ecosystems.The major alpine shrub on the ...Aims Recent studies have shown that alpine meadows on the Qinghai-Tibetan plateau act as significant CO_(2)sinks.On the plateau,alpine shrub meadow is one of typical grassland ecosystems.The major alpine shrub on the plateau is Potentilla fruticosa L.(Rosaceae),which is distributed widely from 3200 to 4000 m.Shrub species play an important role on carbon sequestration in grassland ecosystems.In addition,alpine shrubs are sensitive to climate change such as global warming.Considering global warming,the biomass and productivity of P.fruticosa will increase on Qinghai-Tibetan Plateau.Thus,understanding the carbon dynamics in alpine shrub meadow and the role of shrubs around the upper distribution limit at present is essential to predict the change in carbon sequestration on the plateau.However,the role of shrubs on the carbon dynamics in alpine shrub meadow remains unclear.The objectives of the present study were to evaluate the magnitude of CO_(2)exchange of P.fruticosa shrub patches around the upper distribution limit and to elucidate the role of P.fruticosa on ecosystem CO_(2)fluxes in an alpine meadow.Methods We used the static acrylic chamber technique to measure and estimate the net ecosystem productivity(NEP),ecosystem respiration(Re),and gross primary productivity(GPP)of P.fruticosa shrub patches at three elevations around the species’upper distribution limit.Ecosystem CO_(2)fluxes and environmental factors were measured from 17 to 20 July 2008 at 3400,3600,and 3800 m a.s.l.We examined the maximum GPP at infinite light(GPPmax)and maximum Re(Remax)during the experimental time at each elevation in relation to aboveground biomass and environmental factors,including air and soil temperature,and soil water content.Important Findings Patches of P.fruticosa around the species’upper distribution limit absorbed CO_(2),at least during the daytime.Maximum NEP at infinite light(NEPmax)and GPPmax of shrub patches in the alpine meadow varied among the three elevations,with the highest values at 3400 m and the lowest at 3800 m.GPPmax was positively correlated with the green biomass of P.fruticosa more strongly than with total green biomass,suggesting that P.fruticosa is the major contributor to CO_(2)uptake in the alpine shrub meadow.Air temperature influenced the potential GPPat the shrub-patch scale.Remax was correlated with aboveground biomass and Remax normalized by aboveground biomass was influenced by soil water content.Potentilla fruticosa height(biomass)and frequency increased clearly as elevation decreased,which promotes the large-scale spatial variation of carbon uptake and the strength of the carbon sink at lower elevations.展开更多
In order to explore the feasibility of cryopreservation storage on forest tree seeds, germination of Amorpha fruticosa and Platycladus orientalis seeds with moisture content (MC) changing was tested after storage in l...In order to explore the feasibility of cryopreservation storage on forest tree seeds, germination of Amorpha fruticosa and Platycladus orientalis seeds with moisture content (MC) changing was tested after storage in liquid nitrogen of -196 oC for 30 d. The results showed that both species of seeds can keep high germination percentage after cryopreservation. For A. fruticosa, the germination percentage of seeds was the highest when 4.1% MC was used for storage, and for P. orientalis it was the highest when 6.0% MC was used for storage. It is feasible for both species of seeds to be stored in liquid nitrogen.展开更多
The present study was designed to investigate the chemical constituents of the roots of Cudrania fruticosa Wight. Compounds were isolated by various column chromatographic methods including silica gel, polyamide, seph...The present study was designed to investigate the chemical constituents of the roots of Cudrania fruticosa Wight. Compounds were isolated by various column chromatographic methods including silica gel, polyamide, sephadex LH-20, and semi-preparative HPLC. Their structures were elucidated by a combination of 1D and 2D NMR techniques, mass spectrometry, and chemical methods. Two new xanthones, Cudraxanthone T and U(1-2), along with four known compounds(3-6) were isolated from the roots of Cudrania fruticosa Wight.展开更多
基金supported by Central University Basic Research Funds(2572014CA27),(2572018DB01)Heilongjiang Province Natural Fund(C200913)
文摘In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations and extraction cycles were experimental factors.Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids.The optimal extraction parameters were solid/liquid ratio 1:50 g/mL,ultrasonic power 316 W,ethanol concentration 50%,4 extraction cycles.In the optimized condition,the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g.
基金supported by National Science Foundation of China (No.31270374)Independent Innovation Foundation of Shandong University (No.2011DX008)+1 种基金Natural Science Foundation of Shandong Province,China (No.2009ZRB01875ZR2010CM062)
文摘We investigated the combined effects of soil moisture and light intensity on the growth, development and ecophysiological characteristics of one-year old Amorpha fruticosa seedlings. Soil moisture and light intensity influenced the ecophysiological characteristics of Amorpha fruticosa seedlings. Soil moisture resulted in the decreases of growth rate, individual size, net photosynthetic rate, transpiration rate, leaf water loss rate (WLR), and biomass accumulation of plant parts, and led to increased leaf water saturation deficit (WSD). Under water stress, more photosynthetic products were allocated to root growth. With decreasing light intensity, net photosynthetic rate, transpiration rate, chla/b, water saturation deficit, water use efficiency, water loss rate and biomass accumulation declined, while Chla, Chlb, Chla+b and carotenoids (Car) increased and more photosynthetic products were allocated to stem and leaf growth. Maximum growth vigor, net photosynthetic rate and total biomass accumulation in Amorpha fruticosa seedlings was recorded at 75 80% soil water-holding capacity and 100% light density in greenhouse environments.
基金University Grants Commission,New Delhi,India for providing financial support as JRF
文摘Objective:To evaluate the protective effect of Woodfordia fruticosa Kurz flowers against experimentally induced liver toxicity in rats.Methods:Two different doses of methanol extract of Woodfordia fruticosa(WFM) were evaluated for the hepatoprotective activity against diclofenac sodium induced hepatotoxicity in rats.Various biochemical parameters like alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP),total protein(TP),albumin(ALB),blood urea nitrogen(BUN) from serum;total protein(TP),glutathione (GSH) levels,catalase(CAT) and glutathione peroxidase(GPx) activities from liver were studied; histopathologic changes of liver were also evaluated.Results:WFM effectively reduced the elevated levels of serum ALT,AST,ALP and BUN,enhanced the reduced TP,ALB and hepatic GSH,CAT,GPx activity.The histopathological analysis suggested that WFM decreased the degree of liver fibrosis induced by diclofenac.Conclusions:This study demonstrates the hepatoprotective activity of WFM and thus scientifically support the use of this plant in traditional medicine for the treatment of liver disorders.
基金supported by the Natural Science Foundation of China (31570385)
文摘Dasiphora fruticosa comprises male,female and hermaphrodite plants,which are distributed sympatrically in some populations on the Qinghai-Tibet Plateau.To explore what governs the coexistence of these three sexual phenotypes,we investigated the DNA contents,pollen and ovule production,pollen deposition,and performed hand-pollination in both hermaphroditic and dioecious individuals of D.fruticosa.Flow cytometry confirmed that the DNA content of males and females were almost twice as much as that of the hermaphrodites.Male and female flowers produced more pollen grains and ovules than hermaphroditic flowers.Hand-pollinated treatments showed that unisexual flowers were sterile in one sexual function and bisexual flowers were fertile for both functions,but no sterile seeds were produced between unisexual and bisexual flowers.Our findings imply that polyploidy is related to gender dimorphism,and both are likely to play a strong role in the coexistence of two cryptic biological species of D.fruticosa(low ploidy hermaphroditic species and high ploidy dioecious species)in the Qinghai-Tibet Plateau.
基金supported by the Science and Technology of Dalian(No.2008E11SF168).
文摘A new isoflavone was obstained from the medicinal herb Amorpha fruticosa. It was elucidated asbenzopyran- 12-one, 1,4,10,11 - tetrahydro-6′-[8′-(hydroxymethy1)etheny1]-2,3-dimethoxy-8′-O-β-glucopyranosy1-O-α-D-arabinoside by spectroscopic methods including UV, IR, 1D NMR and 2D NMR techniques. And the activity against acetaminophen-induced hepatotoxicity of this compound was also studied, and found this compound can protect liver obviously from hepatotoxicity induced by acetaminophen (AAP). ?2009 Ting Guo Kang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金Supported by Cleveland State University and Jordan University of Science and Technologygrant number 20130097
文摘Objective:To investigate the role of water-soluble extract of Salvia fruticosa(Creek sage)(S.fruticosa) leaves in reducing both intrinsic cellular and H_2O_2-induced DNA oxidation in cultured human embryonic kidney 293 cells.S.fruiicosa.native to the Eastern-Mediterranean basin,is widely used as a medicinal herb for treatment of various diseases.Methods:Dried leaves of 5.fruticosa were extracted in phosphate buffer saline and purified using both vacuum and high pressure filtrations.Each mL of the preparation contained(7.1±1.0)mg of extract.HEK-293 cells were incubated in one set with S.fruticosa extract in the presence of 0.1 mmol/L H_2O_2,and in the other set with the addition of the extract alone.The DNA oxidation was measured using fluorescence upon fluorescein isothiocyanate derivarization of 8-oxoguanine moieties.The fluorescence was measured using flow cytometry technique.Results:Cells incubated 3 h with 150μL extract and exposed to 0.1 mmol/L H_2O_2 showed lower intensity of fluorescence,and thus lower DNA oxidation.Moreover,cells incubated 3 h with 100μl.of the extract showed lower intensity of fluorescence,and thus lower intrinsic cellular DNA oxidation compared to control(without S.fruticosa).Conchisions:The results from this study suggest that the water-soluble extract of S.fruticosa leaves protects against both H_2O_2-induced and intrinsic cellular DNA oxidation in human embryonic kidney 293 cells.
基金The authors would like to thank the Higher Education Commission of Pakistan for the provision of funds.
文摘Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash crop.Knowledge about the impacts of maternal saline environment on seed attributes of this important euhalophyte is lacking.This study investigated the effects of maternal salinity on yield,size and stress tolerance of S.fruticosa seeds.Seedlings of S.fruticosa were grown in a green net house under increasing maternal salinity levels(0,300,600 and 900 mM NaCl)until seed production.Total yield,size,stress tolerance and germination of the descended seeds under different maternal saline conditions were examined.Plants grown under saline conditions(300,600 and 900 mM NaCl)produce a substantially higher quantity of seeds than plants grown under non-saline condition(0 mM NaCl).Low maternal salinity(300 mM NaCl)improves seed size.Seeds produced under all maternal salinity levels display a higher tolerance to low temperature(night/day thermoperiod of 10℃/20℃),whereas seeds produced under 300 mM NaCl maternal saline condition show a better tolerance to high temperature(night/day thermoperiod of 25℃/35℃)during germination.Seeds from all maternal saline conditions germinate better in the 12 h photoperiod(12 h light/12 h dark)than in the dark(24 h dark);however,seeds produced from low and moderate maternal saline conditions(300 and 600 mM NaCl)show a higher germination in the dark than those from control and high maternal saline conditions(0 and 900 mM NaCl).In general,maternal salinity is found to improve yield,size and stress tolerance of S.fruticosa seeds.
基金Supported by National Natural Science Foundation of China(No.81460652)Key Research and Development and Achievements Transformation Program of Qinghai Province(No.2018-SF-144)Project Funded by Key Laboratory of Medicinal Animal and Plant Resources of Qinghai-Tibet Plateau in Qinghai Province(No.2017-z-y25)
文摘[Objectives]To study the effects of Fruticosa potentilla L.on the expression of key enzymes and hormones related to glucose and lipid metabolism in T2DM rats.[Methods]The ethyl acetate fraction of 95%methanol extract of F.potentilla(MEE)was administered orally to the T2DM rats,and the level of glucose and expression of insulin,resistin,leptin,glucokinase(GK)and glucose-6-phosphatase(G-6-Pase)in the rats were measured and detected.[Results]In the T2DM rats administered with MEE,the postprandial blood glucose level decreased,the expression levels of resistin,leptin and G-6-Pase were down-regulated,and the expression levels of insulin and GK were up-regulated(P<0.05,P<0.01).[Conclusions]F.potentilla can reduce effectively postprandial blood glucose level,regulate the expression of a variety of enzymes and hormones related to glucose and lipid metabolism and recover partially the insulin level in T2DM rats to achieve resistance to T2DM.
文摘A method based on degenerate Oligo primed polymerase chain reaction (PCR) and random amplification of cDNA end (RACE) PCR for cloning a full length cDNA is described. An Amorpha fruticosa cDNA clone encoding UDP glucose pyrophosphorylase (UGP), a key enzyme producing UDP glucose in the synthesis of sucrose and cellulose, is cloned by using this method. We design 5’ RACE primers based on UGPA1 fragment, which obtains from degenerate PCR. Inverse PCR and nested PCR enable cloning of the remainder 5’ and 3’ end fragments of the gene. The deduced amino acid sequence exhibits significant homology with the other UGP genes cloned. This method is more simple and inexpensive than screening cDNA library, and can be easily adapted to clone other genes.
基金JSPS-KOSEF-NSFC A3 Foresight Program(Quantifying and Predicting Terrestrial Carbon Sinks in East Asia:Toward a Network of Climate Change Research).
文摘Aims Recent studies have shown that alpine meadows on the Qinghai-Tibetan plateau act as significant CO_(2)sinks.On the plateau,alpine shrub meadow is one of typical grassland ecosystems.The major alpine shrub on the plateau is Potentilla fruticosa L.(Rosaceae),which is distributed widely from 3200 to 4000 m.Shrub species play an important role on carbon sequestration in grassland ecosystems.In addition,alpine shrubs are sensitive to climate change such as global warming.Considering global warming,the biomass and productivity of P.fruticosa will increase on Qinghai-Tibetan Plateau.Thus,understanding the carbon dynamics in alpine shrub meadow and the role of shrubs around the upper distribution limit at present is essential to predict the change in carbon sequestration on the plateau.However,the role of shrubs on the carbon dynamics in alpine shrub meadow remains unclear.The objectives of the present study were to evaluate the magnitude of CO_(2)exchange of P.fruticosa shrub patches around the upper distribution limit and to elucidate the role of P.fruticosa on ecosystem CO_(2)fluxes in an alpine meadow.Methods We used the static acrylic chamber technique to measure and estimate the net ecosystem productivity(NEP),ecosystem respiration(Re),and gross primary productivity(GPP)of P.fruticosa shrub patches at three elevations around the species’upper distribution limit.Ecosystem CO_(2)fluxes and environmental factors were measured from 17 to 20 July 2008 at 3400,3600,and 3800 m a.s.l.We examined the maximum GPP at infinite light(GPPmax)and maximum Re(Remax)during the experimental time at each elevation in relation to aboveground biomass and environmental factors,including air and soil temperature,and soil water content.Important Findings Patches of P.fruticosa around the species’upper distribution limit absorbed CO_(2),at least during the daytime.Maximum NEP at infinite light(NEPmax)and GPPmax of shrub patches in the alpine meadow varied among the three elevations,with the highest values at 3400 m and the lowest at 3800 m.GPPmax was positively correlated with the green biomass of P.fruticosa more strongly than with total green biomass,suggesting that P.fruticosa is the major contributor to CO_(2)uptake in the alpine shrub meadow.Air temperature influenced the potential GPPat the shrub-patch scale.Remax was correlated with aboveground biomass and Remax normalized by aboveground biomass was influenced by soil water content.Potentilla fruticosa height(biomass)and frequency increased clearly as elevation decreased,which promotes the large-scale spatial variation of carbon uptake and the strength of the carbon sink at lower elevations.
基金subsidized by the project of "Study on Coming back of Vegetation and Technology of Afforestation in Northwest Farming and Pasturing Mixed Area with Serious Corrosion(2006BAD03A0308)"which is a part of "Study on Key Technology of Afforestation in Barren Site (2006BAD03A03)".
文摘In order to explore the feasibility of cryopreservation storage on forest tree seeds, germination of Amorpha fruticosa and Platycladus orientalis seeds with moisture content (MC) changing was tested after storage in liquid nitrogen of -196 oC for 30 d. The results showed that both species of seeds can keep high germination percentage after cryopreservation. For A. fruticosa, the germination percentage of seeds was the highest when 4.1% MC was used for storage, and for P. orientalis it was the highest when 6.0% MC was used for storage. It is feasible for both species of seeds to be stored in liquid nitrogen.
基金supported by the National Natural Science Foundation of China(No.81172949)the Program for Excellent Talents of Liaoning Province of China(No.LR2013058)
文摘The present study was designed to investigate the chemical constituents of the roots of Cudrania fruticosa Wight. Compounds were isolated by various column chromatographic methods including silica gel, polyamide, sephadex LH-20, and semi-preparative HPLC. Their structures were elucidated by a combination of 1D and 2D NMR techniques, mass spectrometry, and chemical methods. Two new xanthones, Cudraxanthone T and U(1-2), along with four known compounds(3-6) were isolated from the roots of Cudrania fruticosa Wight.