The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphor...The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphorylated maize starches with a similar range of amylose content(AC)as controls.The starch property results showed that a higher SPC is associated with lower turbidity,storage and loss modulus after storage,and water solubility,but higher swelling power(SP)and pasting viscosities.These findings suggested that SPC inhibited molecular rearrangement during storage and starch leaching during heating,and enhanced swelling and viscosities due to increased hydration and water uptake caused by the repulsion effect of phosphate groups and a less ordered crystalline structure.Increased SPC also resulted in lower resistant starch(RS)content in a native granular state but higher RS after retrogradation.Pearson correlations further indicated that SPC/C3P/C6P were positively correlated with peak(r^(2)=0.925,0.873 and 0.930,respectively),trough(r^(2)=0.994,0.968 and 0.988,respectively),and final viscosities(r^(2)=0.981,0.968 and 0.971,respectively).Notably,SPC,mainly C3P,exhibited a significantly positive correlation with SP(r^(2)=0.859)and setback viscosity(r^(2)=0.867),whereas SPC,mainly C6P,showed a weak positive correlation with RS after retrogradation(r^(2)=0.746).However,SPC had no significant correlations with water solubility,turbidity and rheology properties,which were more correlated with AC.These findings are helpful for the food industry to select potato starches with desired properties based on their contents of SPC,C3P,or C6P.展开更多
An effective method of producing small neutral carbon dusters Cn （n = 1-6） is described. The small carbon dusters （positive or negative charge or neutral） are formed by plasma which are produced by a high power 53...An effective method of producing small neutral carbon dusters Cn （n = 1-6） is described. The small carbon dusters （positive or negative charge or neutral） are formed by plasma which are produced by a high power 532nm pulse laser ablating the surface of the metal Mn rod to react with small hydrocarbons supplied by a pulse valve, then the neutral carbon clusters are extracted and photo-ionized by another laser （266nm or 355nm） in the ionization region of a linear time-of-flight mass spectrometer. The distributions of the initial neutral carbon dusters are analysed with the ionic species appeared in mass spectra. It is observed that the yield of small carbon dusters with the present method is about 10 times than that of the traditional widely used technology of laser vaporization of graphite.展开更多
Aim and Method Comparative molecular field analysis (CoMFA), a threedimensional quantitative structure-activity relationship (3D-QSAR) method was applied to a novelseries of C-3 substituted 4, 6-dichloioindole-2-carbo...Aim and Method Comparative molecular field analysis (CoMFA), a threedimensional quantitative structure-activity relationship (3D-QSAR) method was applied to a novelseries of C-3 substituted 4, 6-dichloioindole-2-carboxylic acids to study the relationship betweentheir structure and the affinity for the glycine site of the NMDA receptor. Result Hie coefficientsof cross-validation q^2 and non cross-validation r^2 for the model established by the study are0.744 and 0.993, respectively, the value of variance ratio F is 261.343, and standard error estimate(SE) is 0.039. Conclusion These values indicate that the CoMFA model may have a good prediction forthe activity of C-3 substituted 4, 6-dichloroin-dole-2-carboxylic acids. As a consequence, thepredicted activity values of new designed compounds supports our conclusion from the model.展开更多
基金the China Scholarship Council funding(CSC,202006150028)for her PhD study at the University of Copenhagen,Denmark.
文摘The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphorylated maize starches with a similar range of amylose content(AC)as controls.The starch property results showed that a higher SPC is associated with lower turbidity,storage and loss modulus after storage,and water solubility,but higher swelling power(SP)and pasting viscosities.These findings suggested that SPC inhibited molecular rearrangement during storage and starch leaching during heating,and enhanced swelling and viscosities due to increased hydration and water uptake caused by the repulsion effect of phosphate groups and a less ordered crystalline structure.Increased SPC also resulted in lower resistant starch(RS)content in a native granular state but higher RS after retrogradation.Pearson correlations further indicated that SPC/C3P/C6P were positively correlated with peak(r^(2)=0.925,0.873 and 0.930,respectively),trough(r^(2)=0.994,0.968 and 0.988,respectively),and final viscosities(r^(2)=0.981,0.968 and 0.971,respectively).Notably,SPC,mainly C3P,exhibited a significantly positive correlation with SP(r^(2)=0.859)and setback viscosity(r^(2)=0.867),whereas SPC,mainly C6P,showed a weak positive correlation with RS after retrogradation(r^(2)=0.746).However,SPC had no significant correlations with water solubility,turbidity and rheology properties,which were more correlated with AC.These findings are helpful for the food industry to select potato starches with desired properties based on their contents of SPC,C3P,or C6P.
基金Support by the National Natural Science Foundation of China under Grant No 29973039, Department of Education of Jiangsu Province （No JHB05-04）, and Southeast University （No XJ0510195）.
文摘An effective method of producing small neutral carbon dusters Cn （n = 1-6） is described. The small carbon dusters （positive or negative charge or neutral） are formed by plasma which are produced by a high power 532nm pulse laser ablating the surface of the metal Mn rod to react with small hydrocarbons supplied by a pulse valve, then the neutral carbon clusters are extracted and photo-ionized by another laser （266nm or 355nm） in the ionization region of a linear time-of-flight mass spectrometer. The distributions of the initial neutral carbon dusters are analysed with the ionic species appeared in mass spectra. It is observed that the yield of small carbon dusters with the present method is about 10 times than that of the traditional widely used technology of laser vaporization of graphite.
文摘Aim and Method Comparative molecular field analysis (CoMFA), a threedimensional quantitative structure-activity relationship (3D-QSAR) method was applied to a novelseries of C-3 substituted 4, 6-dichloioindole-2-carboxylic acids to study the relationship betweentheir structure and the affinity for the glycine site of the NMDA receptor. Result Hie coefficientsof cross-validation q^2 and non cross-validation r^2 for the model established by the study are0.744 and 0.993, respectively, the value of variance ratio F is 261.343, and standard error estimate(SE) is 0.039. Conclusion These values indicate that the CoMFA model may have a good prediction forthe activity of C-3 substituted 4, 6-dichloroin-dole-2-carboxylic acids. As a consequence, thepredicted activity values of new designed compounds supports our conclusion from the model.
