With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during gra...With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during grain filling, and theirrelationships with the filling rate, gel consistency (GC), alkali spreading value (ASV) and amylose content (AC) werestudied. The results showed that changes in activities of ADPGPase, SSase and Q-enzyme exhibited a single peak duringgrain filling, and the time of the activity peaks for the former two enzymes was earlier than that of the maximum grain-fillingrate (Tmax), and the time reaching the peak for Q-enzyme was synchronous with Tmax. The activities at early grain fillingstage, and the mean and maximum activities of each enzyme during grain filling period were positively and significantly orvery significantly correlated with the mean and maximum grain filling rate and starch content (mg grain-1) in the grains.Activities of ADPGPase at all grain filling stages and those of Q-enzyme at the early and mid filling stages were notsignificantly correlated the cooking quality (GC, ASV and AC). SSase activities at the early filling stage were significantlyand negatively correlated with GC and ASV, and positively correlated with AC. Activities of SSase at mid and late grainfilling stages and Q-enzyme at the late filling stage were significantly and positively correlated with GC and ASV, andnegatively correlated with AC. Spraying zeatin or abscisic acid at early grain filling stage could obviously regulate theactivities of ADPGPase, SSase and Q-enzyme in the grains.展开更多
Based on the sweet potato starch,cationic starch,acetic starch and cationic-acetic compoundedly modified starch were made through chemical denaturalization.The above three kinds of static rheological parameter and dyn...Based on the sweet potato starch,cationic starch,acetic starch and cationic-acetic compoundedly modified starch were made through chemical denaturalization.The above three kinds of static rheological parameter and dynamic rheological parameter were measured,respectively.The experimental result reveals that the thermal stability of starchy viscosity increases after chemical denaturalization.Under the condition of identical shearing rate,the shear stress of cationic-acetic ester compoundedly modified sweet potato starch paste is the largest among these kinds of sweet potato starch.This attributes to a phenomenon of shearing thinning.Furthermore,raw sweet potato starch has a larger gel intensity than that of modified starch.展开更多
[Objectives] Rice-Tartary buckwheat is a special type of Tartary buckwheat with easy hulling thin shell.This study was conducted to characterize the carbohydrate metabolism,quality and yield and provide a basis for fo...[Objectives] Rice-Tartary buckwheat is a special type of Tartary buckwheat with easy hulling thin shell.This study was conducted to characterize the carbohydrate metabolism,quality and yield and provide a basis for food processing and breeding of rice-Tartary buckwheat.[Methods]The local rice-Tartary buckwheat‘cv.Xiaomiqiao’(XMQ) was used to explore the characteristics of photosynthesis,starch synthesis enzyme activities,traits of yield and quality,as compared to Tartary buckwheat‘cv.Jinqiao 2’(JQ2).[Results]XMQ showed significantly lower values of net photosynthetic rate,ADPGase activity and starch synthase activity at one or more periods during grain filling than JQ2.The effective branch number and grain number per plant of XMQ were similar to that of JQ2 regardless of different years,but the 1 000-grain weight was significantly lighter that resulted in the significantly lower yield.XMQ accumulated similar contents of starch(amylose,amylopectin) and protein(glutelin,albumin,prolamin,globulin) to those of JQ2,but exhibited significantly lower flavonoid content.The values of peak viscosity and hot paste viscosity in XMQ were similar to those of JQ2,but the values of cool paste viscosity,breakdown and setback were significantly lower.In conclusion,XMQ showed low yield due to the insufficient of photosynthesis and starch synthesis.XMQ exhibited high nutritional quality as well as normal Tartary buckwheat and stored 18.88 mg/g of flavonoid,that might be consumed as daily diet.[Conclusions]The present results will provide a basis for utilization and improvement of rice-Tartary buckwheat.展开更多
基金supported by the National Natural Science Foundation of China(30370828)the Natural Science Foundation of Jiangsu Province,China(BK2003041)
文摘With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during grain filling, and theirrelationships with the filling rate, gel consistency (GC), alkali spreading value (ASV) and amylose content (AC) werestudied. The results showed that changes in activities of ADPGPase, SSase and Q-enzyme exhibited a single peak duringgrain filling, and the time of the activity peaks for the former two enzymes was earlier than that of the maximum grain-fillingrate (Tmax), and the time reaching the peak for Q-enzyme was synchronous with Tmax. The activities at early grain fillingstage, and the mean and maximum activities of each enzyme during grain filling period were positively and significantly orvery significantly correlated with the mean and maximum grain filling rate and starch content (mg grain-1) in the grains.Activities of ADPGPase at all grain filling stages and those of Q-enzyme at the early and mid filling stages were notsignificantly correlated the cooking quality (GC, ASV and AC). SSase activities at the early filling stage were significantlyand negatively correlated with GC and ASV, and positively correlated with AC. Activities of SSase at mid and late grainfilling stages and Q-enzyme at the late filling stage were significantly and positively correlated with GC and ASV, andnegatively correlated with AC. Spraying zeatin or abscisic acid at early grain filling stage could obviously regulate theactivities of ADPGPase, SSase and Q-enzyme in the grains.
基金Project(2007FJ1007) supported by the Science Foundation of Hunan Province,China
文摘Based on the sweet potato starch,cationic starch,acetic starch and cationic-acetic compoundedly modified starch were made through chemical denaturalization.The above three kinds of static rheological parameter and dynamic rheological parameter were measured,respectively.The experimental result reveals that the thermal stability of starchy viscosity increases after chemical denaturalization.Under the condition of identical shearing rate,the shear stress of cationic-acetic ester compoundedly modified sweet potato starch paste is the largest among these kinds of sweet potato starch.This attributes to a phenomenon of shearing thinning.Furthermore,raw sweet potato starch has a larger gel intensity than that of modified starch.
基金Supported by National Natural Science Foundation of China(31660366)Natural Science Foundation of Guizhou Province(QKH CG[2019]4336,QKH ZC[2019]2298,QKH LH[2017]7359,QKH PT[2017]5726)。
文摘[Objectives] Rice-Tartary buckwheat is a special type of Tartary buckwheat with easy hulling thin shell.This study was conducted to characterize the carbohydrate metabolism,quality and yield and provide a basis for food processing and breeding of rice-Tartary buckwheat.[Methods]The local rice-Tartary buckwheat‘cv.Xiaomiqiao’(XMQ) was used to explore the characteristics of photosynthesis,starch synthesis enzyme activities,traits of yield and quality,as compared to Tartary buckwheat‘cv.Jinqiao 2’(JQ2).[Results]XMQ showed significantly lower values of net photosynthetic rate,ADPGase activity and starch synthase activity at one or more periods during grain filling than JQ2.The effective branch number and grain number per plant of XMQ were similar to that of JQ2 regardless of different years,but the 1 000-grain weight was significantly lighter that resulted in the significantly lower yield.XMQ accumulated similar contents of starch(amylose,amylopectin) and protein(glutelin,albumin,prolamin,globulin) to those of JQ2,but exhibited significantly lower flavonoid content.The values of peak viscosity and hot paste viscosity in XMQ were similar to those of JQ2,but the values of cool paste viscosity,breakdown and setback were significantly lower.In conclusion,XMQ showed low yield due to the insufficient of photosynthesis and starch synthesis.XMQ exhibited high nutritional quality as well as normal Tartary buckwheat and stored 18.88 mg/g of flavonoid,that might be consumed as daily diet.[Conclusions]The present results will provide a basis for utilization and improvement of rice-Tartary buckwheat.
