[ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of...[ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of polysaccharides, the inhibition action on O2^- of polysaccharides, MDA production of lipid peroxidation were measured by Fenton reaction, self oxidation system of C6H3（ OH）3 and TBA method respectively. [ Result] The half scavenging concentration on ·OH of potysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme was 6.79 and 6.75 mg/ml respectively. As to their half inhibition concentration on O2 , the data was 3, 04 and 3.44 mg/ml respectively. Two kinds of Dendrobium polysaccharides bothhad inhibitory actions on lipid peroxidation of liver homogenate induced by auto-oxidation and inducedoxidation, and they could alleviate oxidation damages of mice liver mitochondria induced by Vc-Fe2＋ system. [Conclusion] Two kinds of Dendrobium polysacchaddes both had remarkable anti-oxidation activity in vitro.展开更多
A new bibenzyl derivative, 3,4-dihydroxy-4,5-dimethoxy bibenzyl, was isolated from a orchid Dendrobium moniliforme. The structure elucidation and 1H,13C NMR assignments were achieved by spectroscopic method.
A new bibenzyl glycoside has been isolated from the stems of Dendrobium moniliforme (L.) Sw. (Orchidaceae). Its structure has been identified on the basis of spectroscopic and chemical methods.
Fusarium moniliforme(F.moniliforme) and its secondary metabolite fumonisin pose a severe threat to food safety,and searching for effective antimicrobial agents is a focus of current research.In this study,the secondar...Fusarium moniliforme(F.moniliforme) and its secondary metabolite fumonisin pose a severe threat to food safety,and searching for effective antimicrobial agents is a focus of current research.In this study,the secondary structure of Sub3 was analyzed by circular dichroism,meanwhile,the inhibition rate of Sub3 against spores,mycelia of F.moniliforme and infected maize was studied.To explore the possible inhibition mechanisms,morphological and structural changes of spores treated with Sub3 at0,1/2 MIC(minimum inhibitory concentration) and MIC were observed by scanning electron microscopy and transmission electron microscopy;the cell wall integrity,membrane integrity,reactive oxygen species,mitochondrial membrane potential,ATP synthase activity,redox reactions,and the nuclear damage of F.moniliforme were also investigated.The results showed that Sub3 was mostly in the state of random in deionized water,while mainly showed the β-sheet structure in the hydrophobic environment of 50% Trifluoroethanol(TFE) solution,indicating that Sub3 might generate partial structure deformation when acting on the cell membrane;and its MIC on F.moniliforme spores was 0.2 g/L.Under the 1/2 MIC and MIC,the inhibition rates of Sub3 against F.moniliforme infected maize were 34.3% and75.6%,respectively.The results of inhibition mechanisms revealed that the defective pathogenicity of F.moniliforme caused by Sub3 was attributed to damages on both the cell wall and the cell membrane,which might upset balance of intracellular redox system and mitochondrial energy metabolism and trigger nucleus damage,ultimately leading to cell death.Meanwhile,Sub3 could diminished ATP synthase enzyme activity in a dose-dependent manner.The results provided direct evidence for inhibition of F.moniliforme infection of maize by Sub3,and useful knowledge applicable for food preservation.展开更多
Fusarium moniliforme Sheld.is a rice pathogenic fungus and causes the disease called Bakanae,which has increasingly damaged rice production in the recent years. Trichoderma spp. has been one of the most widely used bi...Fusarium moniliforme Sheld.is a rice pathogenic fungus and causes the disease called Bakanae,which has increasingly damaged rice production in the recent years. Trichoderma spp. has been one of the most widely used biological control agent of plant disease. By geneticaly labelling F. moniliforme with the GFP reporter gene, we have studied the antagonistic action of Trichoderma viride against this pathogenic fungus. The binary GFP reporter vector pCHF3-35S∷GFP was constructed, which carries the gfp gene driven by the CaMv35S promoter. The vector was transformed into F. moniliforme via Agrobacterium.The mycoparasitism of T.viride against F.moniliforme was tested by dual culture and examined with fluorescence microscope. The result of the dual culture showed that the T.viride maintained a strong competitive ability against F. moniliforme , by growing on the top of the pathogen colony. Fluorescence microscope observation indicated that attacked hyphae of F. moniliform were distorted, swollen or broken. This indicate an enzymatic by T.viride to degrade the host cell walls and used the cell contents as a source of nutrients (Fig 1) .展开更多
[ Objective] The study aimed to investigate the effects of silicon on physiology and biochemistry of Dendrobium moniliforme plantlets under low tempera- ture stress. [ Method ] By using Dendrobium monilforme as the ex...[ Objective] The study aimed to investigate the effects of silicon on physiology and biochemistry of Dendrobium moniliforme plantlets under low tempera- ture stress. [ Method ] By using Dendrobium monilforme as the experimental material, different concentrations of Na2SiO3 （0, O. 2, 0.4, 0.6, 0.8, 1.0, 5.0 and 10.0 mmol/L） was added to the basic medium[ 1/2MS ＋ 6-BA （0.1mg/L） ＋ NAA （ 1 mg/L） ＋ agar （7.2 g/L） ＋ sucrose （30 g/L） ] for tissue culture; af- ter hardening and transplanting, Dendrobium moniliforme plantlets were treated under low temperature stress at 4 ~C for 0, 24 and 48 h, in order to investigate the physiological response of Dendrobium ranniliforme leaves to different concentrations of Na2SiO3. [ Result] Under low temperature stress at 4℃, Dendrob/um mon//i- fortns leaves have certain osmotic regulation ability, and the three osmotic regulation substances show different variation trends at different stages. Appropriate con- centration of NshSiO3 can increase the contents of free proline, soluble sugar and soluble protein to varying degrees, reduce MDA content and further improve the cold resistance of Dendrobium moniliforme plantlets. The order of the effects of Na2SiO~ on various physiological indicators is ： free proline 〉 MDA 〉 soluble sugar （or soluble protein）. According to the correlation analysis among various physiological indicators, free proline, soluble sugar, soluble protein and MDA contents can all be used as reference indicators to identify the cold resistance of Dendrobium moniliforme. [ Conclusion] The addition of Na2SiO3 （0.4 retool/L） can moder- ately decrease the thermal energy for normal growth of Dendrobium moniliforme, which is conducive to reducing the cost of cultivation. Key words Na2SiO3 ;Dendrobium monlifforme;Low temperature stress;Physiological and biochemical characteristics展开更多
Fusarium monilljorme, a fungus of established carcinogenic potential, is one of the most common fungal contaminants of maize, millet and other grains in Linxian County, China. Fusarin C, a major product of F. monilljo...Fusarium monilljorme, a fungus of established carcinogenic potential, is one of the most common fungal contaminants of maize, millet and other grains in Linxian County, China. Fusarin C, a major product of F. monilljorme grown on corn in the laboratory, is mutagenic in Salmonella tester strains and in V79 cells. Fusarin C showed several characteristics of malignant transformation including the implantation of the rat esophageal epithelial cell line (RE ?525) in nude mice. The present work demonstrated that fusarin C can induce esophageal and forestomach carcinomas in DBA mice and Wistar rats, and thus the experimental results substantiated further the carcinogenicity of fusarin C.展开更多
文摘[ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of polysaccharides, the inhibition action on O2^- of polysaccharides, MDA production of lipid peroxidation were measured by Fenton reaction, self oxidation system of C6H3（ OH）3 and TBA method respectively. [ Result] The half scavenging concentration on ·OH of potysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme was 6.79 and 6.75 mg/ml respectively. As to their half inhibition concentration on O2 , the data was 3, 04 and 3.44 mg/ml respectively. Two kinds of Dendrobium polysaccharides bothhad inhibitory actions on lipid peroxidation of liver homogenate induced by auto-oxidation and inducedoxidation, and they could alleviate oxidation damages of mice liver mitochondria induced by Vc-Fe2＋ system. [Conclusion] Two kinds of Dendrobium polysacchaddes both had remarkable anti-oxidation activity in vitro.
文摘A new bibenzyl derivative, 3,4-dihydroxy-4,5-dimethoxy bibenzyl, was isolated from a orchid Dendrobium moniliforme. The structure elucidation and 1H,13C NMR assignments were achieved by spectroscopic method.
文摘A new bibenzyl glycoside has been isolated from the stems of Dendrobium moniliforme (L.) Sw. (Orchidaceae). Its structure has been identified on the basis of spectroscopic and chemical methods.
基金sponsored by grants from the Natural Science Foundation of China (31972176)the Cultivation Programme for Young Backbone Teachers in Henan University of Technology (21420114)+1 种基金the Innovative Funds Plan of Henan University of Technology (2020ZKCJ01)the National Key Research and Development Project of China(Project No.2019YFC1605303-04)
文摘Fusarium moniliforme(F.moniliforme) and its secondary metabolite fumonisin pose a severe threat to food safety,and searching for effective antimicrobial agents is a focus of current research.In this study,the secondary structure of Sub3 was analyzed by circular dichroism,meanwhile,the inhibition rate of Sub3 against spores,mycelia of F.moniliforme and infected maize was studied.To explore the possible inhibition mechanisms,morphological and structural changes of spores treated with Sub3 at0,1/2 MIC(minimum inhibitory concentration) and MIC were observed by scanning electron microscopy and transmission electron microscopy;the cell wall integrity,membrane integrity,reactive oxygen species,mitochondrial membrane potential,ATP synthase activity,redox reactions,and the nuclear damage of F.moniliforme were also investigated.The results showed that Sub3 was mostly in the state of random in deionized water,while mainly showed the β-sheet structure in the hydrophobic environment of 50% Trifluoroethanol(TFE) solution,indicating that Sub3 might generate partial structure deformation when acting on the cell membrane;and its MIC on F.moniliforme spores was 0.2 g/L.Under the 1/2 MIC and MIC,the inhibition rates of Sub3 against F.moniliforme infected maize were 34.3% and75.6%,respectively.The results of inhibition mechanisms revealed that the defective pathogenicity of F.moniliforme caused by Sub3 was attributed to damages on both the cell wall and the cell membrane,which might upset balance of intracellular redox system and mitochondrial energy metabolism and trigger nucleus damage,ultimately leading to cell death.Meanwhile,Sub3 could diminished ATP synthase enzyme activity in a dose-dependent manner.The results provided direct evidence for inhibition of F.moniliforme infection of maize by Sub3,and useful knowledge applicable for food preservation.
文摘Fusarium moniliforme Sheld.is a rice pathogenic fungus and causes the disease called Bakanae,which has increasingly damaged rice production in the recent years. Trichoderma spp. has been one of the most widely used biological control agent of plant disease. By geneticaly labelling F. moniliforme with the GFP reporter gene, we have studied the antagonistic action of Trichoderma viride against this pathogenic fungus. The binary GFP reporter vector pCHF3-35S∷GFP was constructed, which carries the gfp gene driven by the CaMv35S promoter. The vector was transformed into F. moniliforme via Agrobacterium.The mycoparasitism of T.viride against F.moniliforme was tested by dual culture and examined with fluorescence microscope. The result of the dual culture showed that the T.viride maintained a strong competitive ability against F. moniliforme , by growing on the top of the pathogen colony. Fluorescence microscope observation indicated that attacked hyphae of F. moniliform were distorted, swollen or broken. This indicate an enzymatic by T.viride to degrade the host cell walls and used the cell contents as a source of nutrients (Fig 1) .
基金Supported by College-level Fund of Sichuan Agricultural University(64070113)
文摘[ Objective] The study aimed to investigate the effects of silicon on physiology and biochemistry of Dendrobium moniliforme plantlets under low tempera- ture stress. [ Method ] By using Dendrobium monilforme as the experimental material, different concentrations of Na2SiO3 （0, O. 2, 0.4, 0.6, 0.8, 1.0, 5.0 and 10.0 mmol/L） was added to the basic medium[ 1/2MS ＋ 6-BA （0.1mg/L） ＋ NAA （ 1 mg/L） ＋ agar （7.2 g/L） ＋ sucrose （30 g/L） ] for tissue culture; af- ter hardening and transplanting, Dendrobium moniliforme plantlets were treated under low temperature stress at 4 ~C for 0, 24 and 48 h, in order to investigate the physiological response of Dendrobium ranniliforme leaves to different concentrations of Na2SiO3. [ Result] Under low temperature stress at 4℃, Dendrob/um mon//i- fortns leaves have certain osmotic regulation ability, and the three osmotic regulation substances show different variation trends at different stages. Appropriate con- centration of NshSiO3 can increase the contents of free proline, soluble sugar and soluble protein to varying degrees, reduce MDA content and further improve the cold resistance of Dendrobium moniliforme plantlets. The order of the effects of Na2SiO~ on various physiological indicators is ： free proline 〉 MDA 〉 soluble sugar （or soluble protein）. According to the correlation analysis among various physiological indicators, free proline, soluble sugar, soluble protein and MDA contents can all be used as reference indicators to identify the cold resistance of Dendrobium moniliforme. [ Conclusion] The addition of Na2SiO3 （0.4 retool/L） can moder- ately decrease the thermal energy for normal growth of Dendrobium moniliforme, which is conducive to reducing the cost of cultivation. Key words Na2SiO3 ;Dendrobium monlifforme;Low temperature stress;Physiological and biochemical characteristics
文摘Fusarium monilljorme, a fungus of established carcinogenic potential, is one of the most common fungal contaminants of maize, millet and other grains in Linxian County, China. Fusarin C, a major product of F. monilljorme grown on corn in the laboratory, is mutagenic in Salmonella tester strains and in V79 cells. Fusarin C showed several characteristics of malignant transformation including the implantation of the rat esophageal epithelial cell line (RE ?525) in nude mice. The present work demonstrated that fusarin C can induce esophageal and forestomach carcinomas in DBA mice and Wistar rats, and thus the experimental results substantiated further the carcinogenicity of fusarin C.
