Previous phytochemical investigation of the leaves and seeds of Pittosporum angustifolium Lodd.led to the isolation and structural elucidation of polyphenols and triterpene saponins.Evaluation for cytotoxicity of isol...Previous phytochemical investigation of the leaves and seeds of Pittosporum angustifolium Lodd.led to the isolation and structural elucidation of polyphenols and triterpene saponins.Evaluation for cytotoxicity of isolated saponins revealed that the predominant structural feature for a cytotoxic activity are acyl substituents at the oleanane aglycon backbone.The present work reports the results of a screening of 10 selected acylated saponins for their potential to inhibit the human DNA-topoisomerase I,giving rise to IC50 values in a range of 2.8-46.5 lM.To clarify the mode of observed cytotoxic action and,moreover,to distinguish from a pure surfactant effect which is commonly accompanied with saponins,these results indicate an involvement of the topoisomerase I and its role as a possible target structure for a cytotoxic activity.In addition,computational predictions of the fitting of saponins to the topoisomerase I-DNA complex,indicate a similar binding mode to that of clinically used topoisomerase I inhibitors.Graphical Abstract Ten acylated triterpene saponins from Pittosporum angustifolium were investigated for their potential to inhibit the human DNA-topoisomerase I and computational predictions of the fitting of saponins to the topoisomerase I-DNA complex were carried out.展开更多
Marine macroalgal sulfated fucose-containing polysaccharides,like fucoidan,have drawn significant attention due to their biotechnological potentials,such as anti-cancer,antioxidant,and anti-cholinesterase activities.T...Marine macroalgal sulfated fucose-containing polysaccharides,like fucoidan,have drawn significant attention due to their biotechnological potentials,such as anti-cancer,antioxidant,and anti-cholinesterase activities.The fucoidan derived from brown macroalgae Sargassum angustifolium species(FSA)was investigated for its cytotoxic effects and alterations in cell proliferation,and cell cycle-related gene expression in the present study occurred on NB4 cell line.The results showed that FSA would induce p53,p21,pro-apoptotic genes and increase expression of the p15 gene as a cell arrest marker.Also,FSA inhibited the anti-apoptotic effect of the Bcl-2 gene and decreased dnmt-1 gene expression.FSA significantly exhibited potent 2,2-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging activity(p<0.05)with an IC_(50) value of 0.157 mg/mL and showed moderate anti-acetylcholinesterase activity with an IC_(50) value of 1.20μg/mL.These results indicated the potential of FSA for the development of therapeutic or preventive agents of cancer and Alzheimer’s disease mainly through cytotoxic effect and AChE(acetylcholinesterase)inhibition as well as additional antioxidant capacities.展开更多
One new Daphniphyllum alkaloid,daphnioldhanol A(1),together with three known ones,were isolated from the stem part of Daphniphyllum angustifolium Hutch.Their structures were elucidated by spectroscopic methods and com...One new Daphniphyllum alkaloid,daphnioldhanol A(1),together with three known ones,were isolated from the stem part of Daphniphyllum angustifolium Hutch.Their structures were elucidated by spectroscopic methods and comparing with the literature data.Compound 2 is a new natural product,but known by synthesis as a racemate.Compound 1 exhibited week cytotoxic activity against Hela cell line with IC50 of 31.9μM.展开更多
Allelopathic plants are important resources for the discovery of bioherbicides.Rosebay willowherb[Chamaenerion angustifolium(L.)Scop.syn.Epilobium angustifolium L.]widely distributes in Western Asia,Europe,and North A...Allelopathic plants are important resources for the discovery of bioherbicides.Rosebay willowherb[Chamaenerion angustifolium(L.)Scop.syn.Epilobium angustifolium L.]widely distributes in Western Asia,Europe,and North America,and behaves as a dominant species within the community due to the production of substances that restrict growth of other plants.This study aims at investigating the allelopathic potential of rosebay willowherb by evaluation of the effects of aqueous extracts from different parts on seed germination and seedling growth in lettuce(Lactuca sativa L.),as well as measuring the accumulation of reactive oxygen species and structural analysis of root tips via scanning electron and transmission electron microscopy.It was observed that the aqueous extracts from the leaves of rosebay willowherb had the strongest inhibitory effect on the germination index,germination energy and total germination of lettuce seeds,followed by capsular fruits and flowers,and the inhibition effect of stems was the weakest.All aqueous extracts(100 mg/mL)showed a significant inhibitory effect on radicle elongation of lettuce seedlings.Additionally,after treatment with the aqueous extract of rosebay willowherb leaves,accumulation of reactive oxygen species increased in columella cells,which correlated with disruption of root tip structure.展开更多
文摘Previous phytochemical investigation of the leaves and seeds of Pittosporum angustifolium Lodd.led to the isolation and structural elucidation of polyphenols and triterpene saponins.Evaluation for cytotoxicity of isolated saponins revealed that the predominant structural feature for a cytotoxic activity are acyl substituents at the oleanane aglycon backbone.The present work reports the results of a screening of 10 selected acylated saponins for their potential to inhibit the human DNA-topoisomerase I,giving rise to IC50 values in a range of 2.8-46.5 lM.To clarify the mode of observed cytotoxic action and,moreover,to distinguish from a pure surfactant effect which is commonly accompanied with saponins,these results indicate an involvement of the topoisomerase I and its role as a possible target structure for a cytotoxic activity.In addition,computational predictions of the fitting of saponins to the topoisomerase I-DNA complex,indicate a similar binding mode to that of clinically used topoisomerase I inhibitors.Graphical Abstract Ten acylated triterpene saponins from Pittosporum angustifolium were investigated for their potential to inhibit the human DNA-topoisomerase I and computational predictions of the fitting of saponins to the topoisomerase I-DNA complex were carried out.
基金The Iran National Science Foundation under contract No. 96015033
文摘Marine macroalgal sulfated fucose-containing polysaccharides,like fucoidan,have drawn significant attention due to their biotechnological potentials,such as anti-cancer,antioxidant,and anti-cholinesterase activities.The fucoidan derived from brown macroalgae Sargassum angustifolium species(FSA)was investigated for its cytotoxic effects and alterations in cell proliferation,and cell cycle-related gene expression in the present study occurred on NB4 cell line.The results showed that FSA would induce p53,p21,pro-apoptotic genes and increase expression of the p15 gene as a cell arrest marker.Also,FSA inhibited the anti-apoptotic effect of the Bcl-2 gene and decreased dnmt-1 gene expression.FSA significantly exhibited potent 2,2-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging activity(p<0.05)with an IC_(50) value of 0.157 mg/mL and showed moderate anti-acetylcholinesterase activity with an IC_(50) value of 1.20μg/mL.These results indicated the potential of FSA for the development of therapeutic or preventive agents of cancer and Alzheimer’s disease mainly through cytotoxic effect and AChE(acetylcholinesterase)inhibition as well as additional antioxidant capacities.
基金the National Natural Science Foundation of China(No.31770392 to YTD)the Science and Technology Program of Yunnan Province(2018ZF013 to YTD)The authors are grateful to the analytical group of the Laboratory of Phytochemistry,Kunming Institute of Botany,Chinese Academy of Sciences,for recorded spectra.
文摘One new Daphniphyllum alkaloid,daphnioldhanol A(1),together with three known ones,were isolated from the stem part of Daphniphyllum angustifolium Hutch.Their structures were elucidated by spectroscopic methods and comparing with the literature data.Compound 2 is a new natural product,but known by synthesis as a racemate.Compound 1 exhibited week cytotoxic activity against Hela cell line with IC50 of 31.9μM.
基金This research was funded by Shandong Provincial Natural Science Foundation,China,Grant No.ZR2018BD030Guangdong Key Laboratory of Marine Material Medica,Grant No.LMM2020-6.
文摘Allelopathic plants are important resources for the discovery of bioherbicides.Rosebay willowherb[Chamaenerion angustifolium(L.)Scop.syn.Epilobium angustifolium L.]widely distributes in Western Asia,Europe,and North America,and behaves as a dominant species within the community due to the production of substances that restrict growth of other plants.This study aims at investigating the allelopathic potential of rosebay willowherb by evaluation of the effects of aqueous extracts from different parts on seed germination and seedling growth in lettuce(Lactuca sativa L.),as well as measuring the accumulation of reactive oxygen species and structural analysis of root tips via scanning electron and transmission electron microscopy.It was observed that the aqueous extracts from the leaves of rosebay willowherb had the strongest inhibitory effect on the germination index,germination energy and total germination of lettuce seeds,followed by capsular fruits and flowers,and the inhibition effect of stems was the weakest.All aqueous extracts(100 mg/mL)showed a significant inhibitory effect on radicle elongation of lettuce seedlings.Additionally,after treatment with the aqueous extract of rosebay willowherb leaves,accumulation of reactive oxygen species increased in columella cells,which correlated with disruption of root tip structure.
