[Objective] The aim was to optimize the culture conditions for asexual reproduction system of Populus euramericana 108.[Method] Orthogonal designs were adopted optimize the culture conditions of the regeneration syste...[Objective] The aim was to optimize the culture conditions for asexual reproduction system of Populus euramericana 108.[Method] Orthogonal designs were adopted optimize the culture conditions of the regeneration system for direct differentiation from leaves and induced callus from stems of P.euramericana 108 aseptic seeding.[Result] Leaves of P.euramericana 108 directly regenerated and differentiated under illumination,while stem segments preferred to regenerate and differentiate through callus induction under illumination.The differentiation medium of adventitious buds from leaves was MS medium （agar 7.0 g/L,pH 6.0,sucrose 20 g/L） added with 0.6 mg/L 6-BA and 0.2 mg/L NAA; callus induction medium of stem segments was WPM solid medium added with 0.75 mg/L KT and 1.5 mg/L 2,4-D.Rooting induction medium for adventitious buds was WPM solid culture （sucrose 30 g/L） added with 2.0 mg/L IBA.[Conclusion] The culture conditions for regeneration system of differentiation from leaves and induced callus of stems were optimized,which provides basis for the construction of tissue culture and genetic transformation system.展开更多
The different resistance of cotton (Gossypium hirsutum L.) cultivars to crude toxin of Verticillium dah/iae(VD) was correlated with the activities of chitinase and β-1, 3-glucanase in callus cells. The activities of ...The different resistance of cotton (Gossypium hirsutum L.) cultivars to crude toxin of Verticillium dah/iae(VD) was correlated with the activities of chitinase and β-1, 3-glucanase in callus cells. The activities of chitinase and β-1, 3-glucanase in the callus cells treated with the VD-toxin were increased to the higher level at earlier time point in resistant cultivars than these in the susceptible cultivars. Exogenous salicylic acid (SA) induced the accumulation of chitinase and β -1,3-glucanase, which resulted in the resistance of callus cells to the VD. toxin. Western blot using a polyclonal antibody against β -1,3-glucanase identified 28 kD protein that was induced by VD-toxin, SA, or VD-toxin plus SA.展开更多
Abstract： A simple optimized microplate-based method to assay endo-1,4-β-mannosidase activity was described as an improved high-throughput screening method. A series of experimental conditions were optimized. It is ...Abstract： A simple optimized microplate-based method to assay endo-1,4-β-mannosidase activity was described as an improved high-throughput screening method. A series of experimental conditions were optimized. It is revealed that the optimum measurement procedure is as follows： adding 50μL of diluted enzyme sample and 50 μL substrate, incubating at 45 ℃ for exactly 5 min in micro-plate, mixing with 100 μL 3,5-dinitrosalicylic acid （DNS） reagent, maintaining at boiling point for 15 rain, cooling down to room temperature before determining the ABS value at 540 nm using an ELISA micro-plate reader. The reaction volume of the optimized microplate-assay is reduced to 200μL from 2 500 μL used in the standard β-mannanase macro-assay. The optimized micro-assay is significantly more sensitive in all of the 643 candidates during endo-1,4-β-mannosidase screening. Statistical analyses show that the sensitivity of the optimized micro-method is significantly greater than that of the macro-assay. The optimized method is convenient, fast, and cheap for high throughput enzyme screening.展开更多
A study was conducted on the isolation of poplar （Populusxeurarnaricana （Dode） Guineir cv. I -72/58） wood components with aqueous acetic acid （AcOH） containing small amounts of sulfuric acid. The reaction time, ...A study was conducted on the isolation of poplar （Populusxeurarnaricana （Dode） Guineir cv. I -72/58） wood components with aqueous acetic acid （AcOH） containing small amounts of sulfuric acid. The reaction time, concentration of acetic acid, ratio of liquor to wood, and concentration of acid catalyst were investigated to examine their effects on the fractionation of wood components. The three main separated components were characterized. The results showed that the optimum conditions for fractionation of poplar wood components were： 0.3% H2SO4 in reaction solution, ratio of liquor to wood 6, reflux time 3 h, and 90% AcOH. The residues were mainly composed of a-Cellulose and hemicellulose, The water insoluble precipitate （acetic acid lignin, AcL） had a low weight-average molecular weight range from 341 to 253 （Mw） and a narrow molecular weight distribution from 1.1 to 1.2. The sugar analysis revealed the solubilized products resulted mainly from hemicellulose and exited as monosaccharides.展开更多
文摘[Objective] The aim was to optimize the culture conditions for asexual reproduction system of Populus euramericana 108.[Method] Orthogonal designs were adopted optimize the culture conditions of the regeneration system for direct differentiation from leaves and induced callus from stems of P.euramericana 108 aseptic seeding.[Result] Leaves of P.euramericana 108 directly regenerated and differentiated under illumination,while stem segments preferred to regenerate and differentiate through callus induction under illumination.The differentiation medium of adventitious buds from leaves was MS medium （agar 7.0 g/L,pH 6.0,sucrose 20 g/L） added with 0.6 mg/L 6-BA and 0.2 mg/L NAA; callus induction medium of stem segments was WPM solid medium added with 0.75 mg/L KT and 1.5 mg/L 2,4-D.Rooting induction medium for adventitious buds was WPM solid culture （sucrose 30 g/L） added with 2.0 mg/L IBA.[Conclusion] The culture conditions for regeneration system of differentiation from leaves and induced callus of stems were optimized,which provides basis for the construction of tissue culture and genetic transformation system.
文摘The different resistance of cotton (Gossypium hirsutum L.) cultivars to crude toxin of Verticillium dah/iae(VD) was correlated with the activities of chitinase and β-1, 3-glucanase in callus cells. The activities of chitinase and β-1, 3-glucanase in the callus cells treated with the VD-toxin were increased to the higher level at earlier time point in resistant cultivars than these in the susceptible cultivars. Exogenous salicylic acid (SA) induced the accumulation of chitinase and β -1,3-glucanase, which resulted in the resistance of callus cells to the VD. toxin. Western blot using a polyclonal antibody against β -1,3-glucanase identified 28 kD protein that was induced by VD-toxin, SA, or VD-toxin plus SA.
基金Project(31000350)supported by the National Natural Science Foundation of China
文摘Abstract： A simple optimized microplate-based method to assay endo-1,4-β-mannosidase activity was described as an improved high-throughput screening method. A series of experimental conditions were optimized. It is revealed that the optimum measurement procedure is as follows： adding 50μL of diluted enzyme sample and 50 μL substrate, incubating at 45 ℃ for exactly 5 min in micro-plate, mixing with 100 μL 3,5-dinitrosalicylic acid （DNS） reagent, maintaining at boiling point for 15 rain, cooling down to room temperature before determining the ABS value at 540 nm using an ELISA micro-plate reader. The reaction volume of the optimized microplate-assay is reduced to 200μL from 2 500 μL used in the standard β-mannanase macro-assay. The optimized micro-assay is significantly more sensitive in all of the 643 candidates during endo-1,4-β-mannosidase screening. Statistical analyses show that the sensitivity of the optimized micro-method is significantly greater than that of the macro-assay. The optimized method is convenient, fast, and cheap for high throughput enzyme screening.
文摘A study was conducted on the isolation of poplar （Populusxeurarnaricana （Dode） Guineir cv. I -72/58） wood components with aqueous acetic acid （AcOH） containing small amounts of sulfuric acid. The reaction time, concentration of acetic acid, ratio of liquor to wood, and concentration of acid catalyst were investigated to examine their effects on the fractionation of wood components. The three main separated components were characterized. The results showed that the optimum conditions for fractionation of poplar wood components were： 0.3% H2SO4 in reaction solution, ratio of liquor to wood 6, reflux time 3 h, and 90% AcOH. The residues were mainly composed of a-Cellulose and hemicellulose, The water insoluble precipitate （acetic acid lignin, AcL） had a low weight-average molecular weight range from 341 to 253 （Mw） and a narrow molecular weight distribution from 1.1 to 1.2. The sugar analysis revealed the solubilized products resulted mainly from hemicellulose and exited as monosaccharides.
