Objective: To investigate the toxicity of aqueous extract of Guibourtia tessmannii(Harms) J. Leonard(G. tessmannii) and evaluate its safety.Methods: NMRI mice were used to determine the acute toxicity of G. tessmannii...Objective: To investigate the toxicity of aqueous extract of Guibourtia tessmannii(Harms) J. Leonard(G. tessmannii) and evaluate its safety.Methods: NMRI mice were used to determine the acute toxicity of G. tessmannii.Increasing concentrations of the plant extracts were administered intraperitoneally or by force-feeding. General behavior and death were monitored and recorded daily for 7 days.In order to determine the sub-acute toxicity of the extract, several doses were administered by oral gavage daily for 28 days in adult Wistar rats. Different parameters were assessed including body weight, food and water intake, biochemical parameters and several vital organ weights.Results: LD50 of 328.78 mg/kg was obtained by i.p. route and more than 5 000 mg/kg was obtained in acute toxicity by oral route. In sub-acute toxicity, no significant alteration was observed in body weight or vital organs, food and water intake, and biochemical parameters.Conclusions: The results showed that the aqueous extract of G. tessmannii has low toxicity intraperitoneally and no sub-acute toxicity via oral intake.展开更多
Triumfetta cordifolia and Bridelia thermifolia are two shrubs from tropical region of Africa. Their gums are traditionally extracted from fresh barks and used in traditional recipes (thickening and aromatization of sa...Triumfetta cordifolia and Bridelia thermifolia are two shrubs from tropical region of Africa. Their gums are traditionally extracted from fresh barks and used in traditional recipes (thickening and aromatization of sauces, improvement of the swelling of maize and bean cakes) and in the process of decantation of traditional beer. In order to valorize these barks in dried form, study of the effect of drying temperature on the rheological properties of their gums was carried out. In this respect, the fresh barks were dried at 40℃, 50℃, 60℃, 70℃ and 80℃ and the viscosity of their extracts was measured. The drying kinetic of the barks showed two falling rate periods represented by two drying constants?k1 and k2. The absolute viscosity of the extracts decreased beyond drying temperatures higher than 70℃ and 80℃respectively for T cordifolia and B. Thermifolia. The decreasing viscosity is attributed mainly to a reorganization of polysaccharide chains. The temperatures range lower than 70℃ could be retained to dry the barks and to extract gums without deteriorating their properties.展开更多
The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated...The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.展开更多
Using 57 Fe Mssbauer effect, the chemical states of iron components were investigated for the barks of Platycladus orientalis, Cedrus deodara and Platanus acerifolia sampled from Lanzhou City, Ch...Using 57 Fe Mssbauer effect, the chemical states of iron components were investigated for the barks of Platycladus orientalis, Cedrus deodara and Platanus acerifolia sampled from Lanzhou City, China. All bark samples showed two overlapping doublets with large and small quadruple splitting. Only Platycladus orientalis's barks exhibited one sextet. Based on Mssbauer parameters, they were attributed to paramagnetic ferrous, paramagnetic ferric and magnetic iron, respectively. For the sampling site which is about 6 kilometers from Lanzhou Steel Factory, the ratio of ferrous to ferric was higher in the sample of Platanus acerifolia's barks, whereas the barks of Platycladus orientalis and Cedrus deodara gave similar values of this ratio. Platycladus orientalis was the most effective in accumulating iron complexes in barks among the three trees. Platanus acerifolia's barks sampled at Lanzhou Steel Factory's area exhibited higher absolute intensities of iron components and lower ration of ferrous to ferric, indicating that industrial air pollution is a contributing factor in accumulating iron compounds in the tree barks of this region.展开更多
Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in ...Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest stands.The research was carried out in the Babiog orski National Park.The research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle gradation.Control plots were located in undisturbed stands.The research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 mm.Wood samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was found.Wood characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture conditions.Poorer decomposition of wood in the gaps regardless of the species is related to lower moisture.The wood species covered by the study differed in the decomposition rate.Spruce wood samples were characterized by a significantly higher decomposition rate compared to beech wood samples.Our research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.展开更多
Spruce-dominated forests are commonly exposed to disturbances associated with mass occurrences of bark beetles.The dieback of trees triggers many physical and chemical processes in the ecosystem resulting in rapid cha...Spruce-dominated forests are commonly exposed to disturbances associated with mass occurrences of bark beetles.The dieback of trees triggers many physical and chemical processes in the ecosystem resulting in rapid changes in the vegetation of the lower forest layers.We aimed to determine the response of non-tree understory vegetation to the mass dieback of Norway spruce(Picea abies)in the first years after the disturbance caused by the European spruce bark beetle(Ips typographus)outbreak.Our study area was the Białowieża Biosphere Reserve covering the Polish part of the emblematic Białowieża Forest,in total 597km^(2).The main data source comprised 3,900 phytosociological relevés(combined spring and summer campaigns)collected from 1,300 systematically distributed forest sites in 2016–2018–the peak years of the bark beetle outbreak.We found that the understory responded immediately to mass spruce dieback,with the most pronounced changes observed in the year of the disturbance and the subsequent year.Shade-tolerant forest species declined in the initial years following the mass spruce dieback,while hemicryptophytes,therophytes,light-demanding species associated with non-forest seminatural communities,as well as water-demanding forest species,expanded.Oxalis acetosella,the most common understory species in the Białowieża Forest,showed a distinct fluctuation pattern,with strong short-term expansion right after spruce dieback,followed by a gradual decline over the next 3–4 years to a cover level 5 percentage points lower than before the disturbance.Thus,our study revealed that mass spruce dieback selectively affects individual herb species,and their responses can be directional and non-directional(fluctuation).Furthermore,we demonstrated that the mass dieback of spruce temporarily increases plant species diversity(α-diversity).展开更多
Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particle...Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particles of fine(0.2 to 1.0 mm),medium(1.0 to 2.5 mm),and coarse(2.5 to 12.0 mm)sizes,derived from the bark of Leucaena leucocephala,were hot-pressed using a heating plate at 175℃for 7 min to create single-layer particleboards measuring 320 mm×320 mm×10 mm,targeting a density of 700 kg/m^(3).Subsequently,the samples were trimmed and conditioned at 20℃and 65%relative humidity.In this study,we compared bark particleboard bonded with urea formaldehyde(UF)adhesive to fine-sized particleboard bonded with demethylated lignin adhesive.The results indicated that bark particleboards utilizing demethylated lignin and UF adhesives exhibited similar qualities.Coarse particleboard showed differences in modulus of elasticity(MOE)and modulus of rupture(MOR),while medium-sized particles exhibited significant variations in moisture content(MC)and water absorption(WA).Furthermore,the thickness swelling of coarse and medium-sized particles under wet and oven-dried conditions exhibited notable distinctions.Overall,the demethylated lignin adhesive extracted from L.leucocephala bark demonstrated similar quality to UF adhesive,with particle size correlating inversely to the strength of the bark particleboard.展开更多
Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this w...Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica extracts.Yield by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of extracts.These are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic acid.The identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion inhibitors.This information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the tannin.Thermomechanical analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.展开更多
Turmoil caused by major refinancing plans of listed companies in the mainland stock market leads regulators to vow stricter approval processes On March 5,shareholders of Ping An Insurance(Group)Co.of China Ltd. (Ping ...Turmoil caused by major refinancing plans of listed companies in the mainland stock market leads regulators to vow stricter approval processes On March 5,shareholders of Ping An Insurance(Group)Co.of China Ltd. (Ping An)passed a refinancing plan of 120 billion yuan($17 billion)at its first interim meeting of the year with an overwhelming 92 percent in favor.展开更多
The fruits of the Sea buckthorn(Hippophae rhamnoides L.)are a popular plant food and a valuable health product.Cultivating plants produces a lot of leaves with fine branches as an unnecessary residue,which needs valor...The fruits of the Sea buckthorn(Hippophae rhamnoides L.)are a popular plant food and a valuable health product.Cultivating plants produces a lot of leaves with fine branches as an unnecessary residue,which needs valorization.The aim of the study was to estimate(by HPLC-MS/MS)the qualitative and quantitative content of polyphenolic compounds in different parts of H.rhamnoides(HR),and to determine the level of antioxidant activity of leaves and fruits(by DPPH,ABTS methods and ferrozine test).Up to 19 compounds were identified in different parts of HR.The fruits are rich in flavonoids,including various glycosides of flavonols isorhamnetin,quercetin,and kaempferol.Two isorhamnetin glycosides were not identified in the leaves,while isorhamnetin-3-rhamnosylglactosides and the ellagitannins hippophaenin B,stachyurin and casuarinin were present only in the leaves of the plant.The bark and roots contained considerably more catechins,but minimal flavonols than the fruits and leaves of HR.The total phenolics and flavonols were most abundant in water infusions from leaves of HR(especially quercetin-3-O-glucoside-7-O-rhamnoside),compared to methanolic extracts.No significant differences in the quantitative and qualitative content of the fresh and dried leaves were detected.The highest antioxidant activity by all three methods was detected in the leaves of HR.In addition to the fruits,the leaves may have a perspective as a source of biologically active substances of HR.展开更多
Infection of plum bark necrosis stem pitting associated virus(PBNSPaV)has been reported in many Prunus species in several countries,causing significant economic losses.The very small proteins encoded by plant viruses ...Infection of plum bark necrosis stem pitting associated virus(PBNSPaV)has been reported in many Prunus species in several countries,causing significant economic losses.The very small proteins encoded by plant viruses are often overlooked due to their short sequences and uncertain significance.However,numerous studies have indicated that they might play important roles in the pathogenesis of virus infection.The role of small hydrophobic protein P6,encoded by the open reading frame 2 of PBNSPaV,has not been well explored.In this study,we amplified the P6 fragment from a PBNSPaV isolate by RT-PCR using specific primers and found that it is 174 bp long and encodes a protein of approximately 6.3 kD with a transmembrane domain.Subcellular localization analysis of P6 proteins in tobacco leaves showed that P6 localizes to the cytomembrane and nuclear membrane.To further clarify the pathogenicity of P6 proteins,we constructed a PVX-P6 expression vector by inserting the p6 fragment into a potato virus X(PVX)-based vector and transformed it into Agrobacterium tumefaciens GV3101.Infiltration of Nicotiana benthamiana(N.benthamiana)with the PVX vector-transformed A.tumefaciens led to slight mosaic symptoms at 14 days of post-inoculation.Meanwhile,infiltration with the PVX-P6 vector-transformed A.tumefaciens resulted in no significant symptoms.These results demonstrated that heterologous expression of P6 in N.benthamiana could not enhance the pathogenicity of PVX.Our study indicates that P6 may not be a potential pathogenic factor associate with the causing of symptoms,and the mode of action of PBNSPaV-P6 protein remains to be further studied.展开更多
基金Supported by the doctoral training funds no.84722652USTM/4802 AC-USTM,of the University of Sciences and Technique of Masuku
文摘Objective: To investigate the toxicity of aqueous extract of Guibourtia tessmannii(Harms) J. Leonard(G. tessmannii) and evaluate its safety.Methods: NMRI mice were used to determine the acute toxicity of G. tessmannii.Increasing concentrations of the plant extracts were administered intraperitoneally or by force-feeding. General behavior and death were monitored and recorded daily for 7 days.In order to determine the sub-acute toxicity of the extract, several doses were administered by oral gavage daily for 28 days in adult Wistar rats. Different parameters were assessed including body weight, food and water intake, biochemical parameters and several vital organ weights.Results: LD50 of 328.78 mg/kg was obtained by i.p. route and more than 5 000 mg/kg was obtained in acute toxicity by oral route. In sub-acute toxicity, no significant alteration was observed in body weight or vital organs, food and water intake, and biochemical parameters.Conclusions: The results showed that the aqueous extract of G. tessmannii has low toxicity intraperitoneally and no sub-acute toxicity via oral intake.
文摘Triumfetta cordifolia and Bridelia thermifolia are two shrubs from tropical region of Africa. Their gums are traditionally extracted from fresh barks and used in traditional recipes (thickening and aromatization of sauces, improvement of the swelling of maize and bean cakes) and in the process of decantation of traditional beer. In order to valorize these barks in dried form, study of the effect of drying temperature on the rheological properties of their gums was carried out. In this respect, the fresh barks were dried at 40℃, 50℃, 60℃, 70℃ and 80℃ and the viscosity of their extracts was measured. The drying kinetic of the barks showed two falling rate periods represented by two drying constants?k1 and k2. The absolute viscosity of the extracts decreased beyond drying temperatures higher than 70℃ and 80℃respectively for T cordifolia and B. Thermifolia. The decreasing viscosity is attributed mainly to a reorganization of polysaccharide chains. The temperatures range lower than 70℃ could be retained to dry the barks and to extract gums without deteriorating their properties.
基金supported by JASSO(Japan Student Services Organization)DPP Grant 2016(Faculty of Forestry,UGM)
文摘The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species.
文摘Using 57 Fe Mssbauer effect, the chemical states of iron components were investigated for the barks of Platycladus orientalis, Cedrus deodara and Platanus acerifolia sampled from Lanzhou City, China. All bark samples showed two overlapping doublets with large and small quadruple splitting. Only Platycladus orientalis's barks exhibited one sextet. Based on Mssbauer parameters, they were attributed to paramagnetic ferrous, paramagnetic ferric and magnetic iron, respectively. For the sampling site which is about 6 kilometers from Lanzhou Steel Factory, the ratio of ferrous to ferric was higher in the sample of Platanus acerifolia's barks, whereas the barks of Platycladus orientalis and Cedrus deodara gave similar values of this ratio. Platycladus orientalis was the most effective in accumulating iron complexes in barks among the three trees. Platanus acerifolia's barks sampled at Lanzhou Steel Factory's area exhibited higher absolute intensities of iron components and lower ration of ferrous to ferric, indicating that industrial air pollution is a contributing factor in accumulating iron compounds in the tree barks of this region.
基金financed by the National Science Centre,Poland:decision no.DEC 2020/39/B/NZ9/00372 and decision no.DEC-2021/43/O/NZ9/00066。
文摘Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest stands.The research was carried out in the Babiog orski National Park.The research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle gradation.Control plots were located in undisturbed stands.The research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 mm.Wood samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was found.Wood characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture conditions.Poorer decomposition of wood in the gaps regardless of the species is related to lower moisture.The wood species covered by the study differed in the decomposition rate.Spruce wood samples were characterized by a significantly higher decomposition rate compared to beech wood samples.Our research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.
文摘Spruce-dominated forests are commonly exposed to disturbances associated with mass occurrences of bark beetles.The dieback of trees triggers many physical and chemical processes in the ecosystem resulting in rapid changes in the vegetation of the lower forest layers.We aimed to determine the response of non-tree understory vegetation to the mass dieback of Norway spruce(Picea abies)in the first years after the disturbance caused by the European spruce bark beetle(Ips typographus)outbreak.Our study area was the Białowieża Biosphere Reserve covering the Polish part of the emblematic Białowieża Forest,in total 597km^(2).The main data source comprised 3,900 phytosociological relevés(combined spring and summer campaigns)collected from 1,300 systematically distributed forest sites in 2016–2018–the peak years of the bark beetle outbreak.We found that the understory responded immediately to mass spruce dieback,with the most pronounced changes observed in the year of the disturbance and the subsequent year.Shade-tolerant forest species declined in the initial years following the mass spruce dieback,while hemicryptophytes,therophytes,light-demanding species associated with non-forest seminatural communities,as well as water-demanding forest species,expanded.Oxalis acetosella,the most common understory species in the Białowieża Forest,showed a distinct fluctuation pattern,with strong short-term expansion right after spruce dieback,followed by a gradual decline over the next 3–4 years to a cover level 5 percentage points lower than before the disturbance.Thus,our study revealed that mass spruce dieback selectively affects individual herb species,and their responses can be directional and non-directional(fluctuation).Furthermore,we demonstrated that the mass dieback of spruce temporarily increases plant species diversity(α-diversity).
基金the financial support provided by UMS Great(GUG0217-1/2018),which played a crucial role in the completion of this study.
文摘Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particles of fine(0.2 to 1.0 mm),medium(1.0 to 2.5 mm),and coarse(2.5 to 12.0 mm)sizes,derived from the bark of Leucaena leucocephala,were hot-pressed using a heating plate at 175℃for 7 min to create single-layer particleboards measuring 320 mm×320 mm×10 mm,targeting a density of 700 kg/m^(3).Subsequently,the samples were trimmed and conditioned at 20℃and 65%relative humidity.In this study,we compared bark particleboard bonded with urea formaldehyde(UF)adhesive to fine-sized particleboard bonded with demethylated lignin adhesive.The results indicated that bark particleboards utilizing demethylated lignin and UF adhesives exhibited similar qualities.Coarse particleboard showed differences in modulus of elasticity(MOE)and modulus of rupture(MOR),while medium-sized particles exhibited significant variations in moisture content(MC)and water absorption(WA).Furthermore,the thickness swelling of coarse and medium-sized particles under wet and oven-dried conditions exhibited notable distinctions.Overall,the demethylated lignin adhesive extracted from L.leucocephala bark demonstrated similar quality to UF adhesive,with particle size correlating inversely to the strength of the bark particleboard.
基金supported by the Institut de la Francophonie pour le Developpement Durable(IFDD/Canada)/Projet de Deploiement des Technologies et Innovations Environnementales(PDTIE)funded by Organisation Internationale de la Francophonie(OIF)the Organisation of African,Caribbean and Pacific States and the European Union(EU)(FED/220/421-370)the Local Materials Promotion Authority(MIPROMALO)of the Ministry of Scientific Research and Innovation of Cameroon who made it possible for this scientific work to be carried out.
文摘Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica extracts.Yield by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of extracts.These are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic acid.The identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion inhibitors.This information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the tannin.Thermomechanical analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.
文摘Turmoil caused by major refinancing plans of listed companies in the mainland stock market leads regulators to vow stricter approval processes On March 5,shareholders of Ping An Insurance(Group)Co.of China Ltd. (Ping An)passed a refinancing plan of 120 billion yuan($17 billion)at its first interim meeting of the year with an overwhelming 92 percent in favor.
基金supported by the European Union in the MSCA4Ukraine project ID Number 1232466.
文摘The fruits of the Sea buckthorn(Hippophae rhamnoides L.)are a popular plant food and a valuable health product.Cultivating plants produces a lot of leaves with fine branches as an unnecessary residue,which needs valorization.The aim of the study was to estimate(by HPLC-MS/MS)the qualitative and quantitative content of polyphenolic compounds in different parts of H.rhamnoides(HR),and to determine the level of antioxidant activity of leaves and fruits(by DPPH,ABTS methods and ferrozine test).Up to 19 compounds were identified in different parts of HR.The fruits are rich in flavonoids,including various glycosides of flavonols isorhamnetin,quercetin,and kaempferol.Two isorhamnetin glycosides were not identified in the leaves,while isorhamnetin-3-rhamnosylglactosides and the ellagitannins hippophaenin B,stachyurin and casuarinin were present only in the leaves of the plant.The bark and roots contained considerably more catechins,but minimal flavonols than the fruits and leaves of HR.The total phenolics and flavonols were most abundant in water infusions from leaves of HR(especially quercetin-3-O-glucoside-7-O-rhamnoside),compared to methanolic extracts.No significant differences in the quantitative and qualitative content of the fresh and dried leaves were detected.The highest antioxidant activity by all three methods was detected in the leaves of HR.In addition to the fruits,the leaves may have a perspective as a source of biologically active substances of HR.
基金funded by the National Natural Science Foundation of China(32102143)Shandong Province Natural Sciences Foundation of China(ZR2019PC011 and ZR2020QC122)+1 种基金Scientific Research Foundation for Ph.D.Programs of Zaozhuang University(2018BS040 and 2018BS042)Science and Technology Program of Zaozhuang(2019NS03).
文摘Infection of plum bark necrosis stem pitting associated virus(PBNSPaV)has been reported in many Prunus species in several countries,causing significant economic losses.The very small proteins encoded by plant viruses are often overlooked due to their short sequences and uncertain significance.However,numerous studies have indicated that they might play important roles in the pathogenesis of virus infection.The role of small hydrophobic protein P6,encoded by the open reading frame 2 of PBNSPaV,has not been well explored.In this study,we amplified the P6 fragment from a PBNSPaV isolate by RT-PCR using specific primers and found that it is 174 bp long and encodes a protein of approximately 6.3 kD with a transmembrane domain.Subcellular localization analysis of P6 proteins in tobacco leaves showed that P6 localizes to the cytomembrane and nuclear membrane.To further clarify the pathogenicity of P6 proteins,we constructed a PVX-P6 expression vector by inserting the p6 fragment into a potato virus X(PVX)-based vector and transformed it into Agrobacterium tumefaciens GV3101.Infiltration of Nicotiana benthamiana(N.benthamiana)with the PVX vector-transformed A.tumefaciens led to slight mosaic symptoms at 14 days of post-inoculation.Meanwhile,infiltration with the PVX-P6 vector-transformed A.tumefaciens resulted in no significant symptoms.These results demonstrated that heterologous expression of P6 in N.benthamiana could not enhance the pathogenicity of PVX.Our study indicates that P6 may not be a potential pathogenic factor associate with the causing of symptoms,and the mode of action of PBNSPaV-P6 protein remains to be further studied.