Sweetpotato starch thermal properties and its noodle quality were analyzed using a rapid predictive method based on near-infrared spectroscopy （NIRS）. This method was established based on a total of 93 sweetpotato g...Sweetpotato starch thermal properties and its noodle quality were analyzed using a rapid predictive method based on near-infrared spectroscopy （NIRS）. This method was established based on a total of 93 sweetpotato genotypes with diverse genetic background. Starch samples were scanned by NIRS and analyzed for quality properties by reference methods. Results of statistical modelling indicated that NIRS was reasonably accurate in predicting gelatinization onset temperature （To） （standard error of prediction SEP=2.014 ℃, coefficient of determination RSQ=0.85）, gelatinization peak temperature （Tp） （SEP=-1.371 ℃, RSQ=0.89）, gelatinization temperature range （Tr） （SEP=2.234 ℃, RSQ=0.86）, and cooling resistance （CR） （SEP=0.528, RSQ=0.89）. Gelatinization completion temperature （To）, enthalpy of gelatinization （△H）, cooling loss （CL） and swelling degree （SWD）, were modelled less well with RSQ between 0.63 and 0.84. The present results suggested that the NIRS based method was sufficiently accurate and practical for routine analysis of sweetpotato starch and its noodle quality.展开更多
Jasmonate ZIM-domain(JAZ)proteins are key repressors of the jasmonate signaling pathway and are involved in plant stress responses.However,their roles in starch biosynthesis in cereal crops remain unclear.In this stud...Jasmonate ZIM-domain(JAZ)proteins are key repressors of the jasmonate signaling pathway and are involved in plant stress responses.However,their roles in starch biosynthesis in cereal crops remain unclear.In this study,we identified a locus associated with starch content on chromosome 5A by a genome-wide association study(GWAS).At this locus,a gene(TraesCS5A02G204900)encoding a JAZ protein(TaJAZ1)was found to be highly expressed in grains.CRISPR/Cas9-induced mutants were generated to investigate the role of TaJAZ1 in starch biosynthesis.Phenotypic characterization revealed significant alterations in starch granule size,crystallinity,and digestibility.Specifically,the two mutant lines(tajaz1-abd#1 and tajaz1-abd#2)exhibited increased total starch(12.5%and 17.6%,respectively),amylose(79.3%and 72.1%,respectively),resistant starch(88.5%and 96.8%,respectively),and grain yield per plant(103.8%and 58.8%,respectively).Furthermore,the mutation of TaJAZ1 significantly increased the expression levels of TaSBEI,TaAGPS1,TaAGPL1 and TaGBSSI,but decreased the expression levels of TaSSIIa,TaSSIIb and TaSBEIIa by binding to their promoters.Taken together,our results demonstrate that TaJAZ1 is a negative regulator of starch biosynthesis and grain yield.These findings not only provide novel insights into wheat starch biosynthesis regulation,but also contribute to potential genes for breeding wheat varieties of better quality and higher yield.展开更多
Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results...Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.展开更多
For the purpose of alleviating the adverse effect of paste aging on the properties of corn starch film, a series of electroneutrally quaternized/sulfosuccinylated starches（EQSS） with different degrees of substitutio...For the purpose of alleviating the adverse effect of paste aging on the properties of corn starch film, a series of electroneutrally quaternized/sulfosuccinylated starches（EQSS） with different degrees of substitution（DS） were synthesized via the quaternization/sulfosuccination of acid-thinned corn starch（ATS） by varying the amounts of N-（3-chloro-2-hydroxypropl） trimethylammonium chloride, maleic anhydride, and sodium hydrogen sulfite. The influence of paste aging on the properties of starch film cast from heat-induced starch paste was investigated and the properties were explored in terms of tensile strength, elongation, work at break, degree of crystallinity, and flex-fatigue resistance. The experimental results showed that the paste ageing generated adverse influence on the elongation, work at break, and flex-fatigue resistance of starch film. Further experiments showed that electroneutral quaternization/sulfosuccination of starch were able to alleviate the negative effect of paste ageing on the elongation, work at break, and flex-fatigue resistance, thereby obviously enhancing the elongation, work at break and flex-fatigue resistance, and thus reducing the drawback of brittleness. The enhancement depended on the amounts of the substituents introduced. With the increase in DS value, the elongation and work at break as well as flex-fatigue resistance continuously rose, whereas the tensile strength gradually reduced.展开更多
The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total...The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total starch and amylose content as compared to DF. Starch granules of DF were oval shape with rough surface while DS and PDS were relatively smooth by SEM. According to XRD measurements, FT-IR spectroscopy and 13 C CP/MAS NMR spectroscopy, all samples displayed C-type crystalline pattern, and PDS displayed the highest relative crystallinity and short-range order structure. However, DF contained the greatest content of the amorphous-phase. DF displayed the absorption peaks at 1730 and 1560 cm^-1 related to the characteristic groups of lipid and protein using FT-IR spectroscopy. Furthermore, DF exhibited significantly higher pasting temperature while DS displayed the great peak and breakdown viscosity, as well as PDS had the highest setback and final viscosity, presumably due to the chemical composition and structural differences. DF exhibited the highest gelatinization temperature whereas PDS displayed the greatest gelatinization enthalpy. The pasting and gelatinization properties of flour and starch might be related to the relative crystallinity, short-range order structure or the interactions between starch and its associated compounds. The results allow the improvement in the manufacture of Dioscorea opposita Thunb. flour and starch with desirable pasting and gelatinization properties.展开更多
Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synt...Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.展开更多
A plastidic adenosine triphosphate（ATP）/adenosine diphosphate（ADP） transporter（AATP） is responsible for importing ATP from the cytosol into plastids. In dicotyledonous plants, increasing ATP supply is a potentia...A plastidic adenosine triphosphate（ATP）/adenosine diphosphate（ADP） transporter（AATP） is responsible for importing ATP from the cytosol into plastids. In dicotyledonous plants, increasing ATP supply is a potential way to facilitate anabolic synthesis in heterotrophic plastids. In this study, a gene encoding the AATP protein, named Ib AATP, was isolated from sweetpotato（Ipomoea batatas（L.） Lam.）. Transcripts of Ib AATP were predominantly detected in the storage roots and leaves and were induced by exogenous sucrose and subjected to circadian rhythm. Transient expression of Ib AATP in tobacco and onion epidermal cells revealed the plastidic localization of Ib AATP. The overexpression of Ib AATP in sweetpotato significantly increased the starch and amylose contents and led to enlarged starch granules. The IbA ATP-overexpressing plants showed altered fine structure of amylopectin, which contained an increased proportion of chains with a degree of polymerization（DP） of 10–23 and a reduced number of chains with a DP of 5–9 and 24–40. In addition, starch from the transgenic plants exhibited different pasting properties. The transcript levels of starch biosynthetic genes, including Ib AGP, Ib GBSSI, Ib SSIIV, and Ib SBE, were differentially regulated in the transgenic plants. These results revealed the explicit role of Ib AATP in the starch biosynthesis of sweetpotato and indicated that this gene has the potential to be used to improve starch content and quality in sweetpotato and other plants.展开更多
A facile and green synthetic approach for fabrication of starch-stabilized magnetite nanoparticles was implemented at moderate temperature. This synthesis involved the use of iron salts, potato starch,sodium hydroxide...A facile and green synthetic approach for fabrication of starch-stabilized magnetite nanoparticles was implemented at moderate temperature. This synthesis involved the use of iron salts, potato starch,sodium hydroxide and deionized water as iron precursors, stabilizer, reducing agent and solvent respectively. The nanoparticles（NPs） were characterized by UV-vis, PXRD, HR-TEM, FESEM, EDX, VSM and FT-IR spectroscopy. The ultrasonic assisted co-precipitation technique provides well formation of highly distributed starch/Fe3O4-NPs. Based on UV–vis analysis, the sample showed the characteristic of surface plasmon resonance in the presence of Fe3O4-NPs. The PXRD pattern depicted the characteristic of the cubic lattice structure of Fe3O4-NPs. HR-TEM analysis showed the good dispersion of NPs with a mean diameter and standard deviation of 10.68 4.207 nm. The d spacing measured from the lattice images were found to be around 0.30 nm and 0.52 nm attributed to the Fe3O4 and starch, respectively. FESEM analysis confirmed the formation of spherical starch/Fe3O4-NPs with the emission of elements of C, O and Fe by EDX analysis. The magnetic properties illustrated by VSM analysis indicated that the as synthesized sample has a saturation magnetization and coercivity of 5.30 emu/g and 22.898 G respectively.Additionally, the FTIR analysis confirmed the binding of starch with Fe3O4-NPs. This method was cost effective, facile and eco-friendly alternative for preparation of NPs.展开更多
Starch is the major component of wheat flour and serves as a multifunctional ingredient in food industry. The objective of the present study was to investigate starch granule size distribution of Chinese wheat cultiva...Starch is the major component of wheat flour and serves as a multifunctional ingredient in food industry. The objective of the present study was to investigate starch granule size distribution of Chinese wheat cultivars, and to compare structure and functionality of starches in four leading cultivars Zhongmai 175, CA12092, Lunxuan 987, and Zhongyou 206. A wide variation in volume percentages of A- and B-type starch granules among genotypes was observed. Volume percentages of A- and B-type granules had ranges of 68.4–88.9% and 9.7–27.9% in the first cropping seasons, 74.1–90.1% and 7.2–25.3% in the second. Wheat cultivars with higher volume percentages of A- and B-type granules could serve as parents in breeding program for selecting high and low amylose wheat cultivars, respectively. In comparison with the B-type starch granules, the A-type granules starch showed difference in three aspects：（1） higher amount of ordered short-range structure and a lower relative crystallinity,（2） higher gelatinization onset（To） temperatures and enthalpies（ΔH）, and lower gelatinization conclusion temperatures（Tc）,（3） greater peak, though, and final viscosity, and lower breakdown viscosity and pasting temperature. It provides important information for breeders to develop potentially useful cultivars with particular functional properties of their starches suited to specific applications.展开更多
Sweetpotato(Ipomoea batatas)starch is in high demand globally as a food and industrial product.However,the regulatory mechanisms governing starch biosynthesis and starch properties in this important crop remain largel...Sweetpotato(Ipomoea batatas)starch is in high demand globally as a food and industrial product.However,the regulatory mechanisms governing starch biosynthesis and starch properties in this important crop remain largely unknown.Here we identified a natural allelic variant in the promoter of IbNAC22,encoding a NAC(NAM,ATAF1/2,and CUC2)transcription factor,which is closely linked to starch content in sweetpotato.In high-starch sweetpotato varieties,the T/C haplotype and a 13-bp deletion in the IbNAC22 promoter resulted in higher transcriptional activity.The high-starch IbNAC22 haplotype is more prevalent in regions of China where the sweetpotato starch industry is well developed,indicating that this advantageous allele type has been utilized in breeding starchy sweetpotato varieties in China.IbNAC22 is highly expressed in storage roots and starch-rich sweetpotato accessions.Overexpression of IbNAC22 significantly improved starch and amylose contents,as well as granule size and gelatinization temperature,and decreased starch crystallinity,whereas IbNAC22 knockdown had the opposite effects.IbNAC22 directly activates the expression of IbGBSSI,a key gene for amylose biosynthesis,but suppresses the expression of IbSBEI,a key gene for amylopectin biosynthesis.IbNAC22 directly interacts with IbNF-YA10.Overexpressing of IbNF-YA10 significantly improved starch and amylose contents,and starch gelatinization temperature,but decreased granule size,crystallinity,and amylopectin chain length distribution.IbNF-YA10 directly activates IbAGPL and IbGBSSI,which are key genes involved in starch and amylose biosynthesis.IbNAC22–IbNF-YA10 heterodimers further enhance the IbNF-YA10-induced activation of IbAGPL and IbGBSSI.These findings increase our understanding of starch biosynthesis and starch properties and provide strategies and candidate genes for the improvement of starchy root and tuber crops.展开更多
Dumpling is one of the most important traditional wheat products in China. Dumpling quality is determined by the characteristics of both flour and filling, thus improvement of flour quality plays an important role in ...Dumpling is one of the most important traditional wheat products in China. Dumpling quality is determined by the characteristics of both flour and filling, thus improvement of flour quality plays an important role in improving dumpling quality. Thirty-nine Shandong winter wheat cultivars and advanced lines sown in Jinan, Shandong Province, China, in the 2008-2009 cropping season were used to determine genetic variation in Chinese raw dumpling quality and its relationship with flour characteristics. Large variations were observed for protein quality parameters in comparison with starch properties. Variation in color of the raw dumpling sheet was broader than that of sensory evaluation parameters of boiled dumpling among tested wheat cultivars, indicating the large influence of filling on dumpling color. Two cultivars, Jimai 20 and Zimai 12, were identified as possessing very good quality of raw dumpling, and 21 cultivars and advanced lines showed good quality. Protein and total starch content influenced the L＊ value of raw dumpling sheets. L＂ value at 0 and 2 h after sheeting were significantly influenced by protein content （r=-0.46 and -0.52, P〈0.01） and total starch content （r=0.55 and 0.57, P〈0.01）, respectively. Flour yellow pigment was significantly corrected with a＊ （r=-0.67 and -0.62, P〈0.01） and b＊ （r=0.87 and 0.84, P〈0.01） value of raw dumpling sheets at 0 and 2 h after sheeting, respectively. Gluten strength parameters such as farinograph mixing tolerance index （MTI, r=-0.55, P〈0.01） were positively associated with appearance. MTI and energy were also significantly and positively correlated with elasticity of raw dumpling, with r=-0.54 and 0.47 （P〈0.01）. The positive relationships between peak viscosity （r=0.51, P〈0.01）, breakdown （r=0.54, P〈0.01）, and smoothness of raw dumpling were also observed. Therefore, it is suggested that breeding programs should give more attention to gluten strength and starch pasting parameters for raw dumpling quality improvement.展开更多
基金Project supported by the Hi-Tech Research and Development Pro-gram (863) of China (No. 2004AA241180), and the Scientific Re-search Foundation for the Returned Overseas Chinese Scholars of State Education Ministry, and the Science and Technology Depart-ment of Zhejiang Province, China
文摘Sweetpotato starch thermal properties and its noodle quality were analyzed using a rapid predictive method based on near-infrared spectroscopy （NIRS）. This method was established based on a total of 93 sweetpotato genotypes with diverse genetic background. Starch samples were scanned by NIRS and analyzed for quality properties by reference methods. Results of statistical modelling indicated that NIRS was reasonably accurate in predicting gelatinization onset temperature （To） （standard error of prediction SEP=2.014 ℃, coefficient of determination RSQ=0.85）, gelatinization peak temperature （Tp） （SEP=-1.371 ℃, RSQ=0.89）, gelatinization temperature range （Tr） （SEP=2.234 ℃, RSQ=0.86）, and cooling resistance （CR） （SEP=0.528, RSQ=0.89）. Gelatinization completion temperature （To）, enthalpy of gelatinization （△H）, cooling loss （CL） and swelling degree （SWD）, were modelled less well with RSQ between 0.63 and 0.84. The present results suggested that the NIRS based method was sufficiently accurate and practical for routine analysis of sweetpotato starch and its noodle quality.
基金financially supported by the projects of National Key Research and Development Program of China(2021YFF1000203)the National Natural Science Foundation of China(32171924)+1 种基金the Support Plan for Scientific and Technological Innovation Talents in Colleges and Universities of Henan Province(23HASTIT038)the Graduate Joint Training Base Project of Henan Province(YJS2024JD18).
文摘Jasmonate ZIM-domain(JAZ)proteins are key repressors of the jasmonate signaling pathway and are involved in plant stress responses.However,their roles in starch biosynthesis in cereal crops remain unclear.In this study,we identified a locus associated with starch content on chromosome 5A by a genome-wide association study(GWAS).At this locus,a gene(TraesCS5A02G204900)encoding a JAZ protein(TaJAZ1)was found to be highly expressed in grains.CRISPR/Cas9-induced mutants were generated to investigate the role of TaJAZ1 in starch biosynthesis.Phenotypic characterization revealed significant alterations in starch granule size,crystallinity,and digestibility.Specifically,the two mutant lines(tajaz1-abd#1 and tajaz1-abd#2)exhibited increased total starch(12.5%and 17.6%,respectively),amylose(79.3%and 72.1%,respectively),resistant starch(88.5%and 96.8%,respectively),and grain yield per plant(103.8%and 58.8%,respectively).Furthermore,the mutation of TaJAZ1 significantly increased the expression levels of TaSBEI,TaAGPS1,TaAGPL1 and TaGBSSI,but decreased the expression levels of TaSSIIa,TaSSIIb and TaSBEIIa by binding to their promoters.Taken together,our results demonstrate that TaJAZ1 is a negative regulator of starch biosynthesis and grain yield.These findings not only provide novel insights into wheat starch biosynthesis regulation,but also contribute to potential genes for breeding wheat varieties of better quality and higher yield.
基金Funded by the Fundamental Research Funds for the Central Universities(DL13CB13)the China Postdoctoral Science Foundation Funded Project(No.2014M550178)the National Natural Science Foundation of China(No.31200442)
文摘Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.
基金Funded by the Open Project Program of Key Laboratory of Eco-Textiles,Ministry of Education,China(No.KLET0617)the Scientific Research Fund of Talent Introduction of Anhui Polytechnic University(No.2016YQQ004)
文摘For the purpose of alleviating the adverse effect of paste aging on the properties of corn starch film, a series of electroneutrally quaternized/sulfosuccinylated starches（EQSS） with different degrees of substitution（DS） were synthesized via the quaternization/sulfosuccination of acid-thinned corn starch（ATS） by varying the amounts of N-（3-chloro-2-hydroxypropl） trimethylammonium chloride, maleic anhydride, and sodium hydrogen sulfite. The influence of paste aging on the properties of starch film cast from heat-induced starch paste was investigated and the properties were explored in terms of tensile strength, elongation, work at break, degree of crystallinity, and flex-fatigue resistance. The experimental results showed that the paste ageing generated adverse influence on the elongation, work at break, and flex-fatigue resistance of starch film. Further experiments showed that electroneutral quaternization/sulfosuccination of starch were able to alleviate the negative effect of paste ageing on the elongation, work at break, and flex-fatigue resistance, thereby obviously enhancing the elongation, work at break and flex-fatigue resistance, and thus reducing the drawback of brittleness. The enhancement depended on the amounts of the substituents introduced. With the increase in DS value, the elongation and work at break as well as flex-fatigue resistance continuously rose, whereas the tensile strength gradually reduced.
基金Supported by the National Natural Science Foundation of China(No.31701552)Leading Talents Support Program of Science and Technology Innovation in Fujian Province(KRC16002A)Excellent Talents Support Program of Colleges and Universities in Fujian Province(JA14094)
文摘The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total starch and amylose content as compared to DF. Starch granules of DF were oval shape with rough surface while DS and PDS were relatively smooth by SEM. According to XRD measurements, FT-IR spectroscopy and 13 C CP/MAS NMR spectroscopy, all samples displayed C-type crystalline pattern, and PDS displayed the highest relative crystallinity and short-range order structure. However, DF contained the greatest content of the amorphous-phase. DF displayed the absorption peaks at 1730 and 1560 cm^-1 related to the characteristic groups of lipid and protein using FT-IR spectroscopy. Furthermore, DF exhibited significantly higher pasting temperature while DS displayed the great peak and breakdown viscosity, as well as PDS had the highest setback and final viscosity, presumably due to the chemical composition and structural differences. DF exhibited the highest gelatinization temperature whereas PDS displayed the greatest gelatinization enthalpy. The pasting and gelatinization properties of flour and starch might be related to the relative crystallinity, short-range order structure or the interactions between starch and its associated compounds. The results allow the improvement in the manufacture of Dioscorea opposita Thunb. flour and starch with desirable pasting and gelatinization properties.
基金supported by the Major Program of National Agricultural Science and Technology of China(NK20220607)the Sichuan Science and Technology Program,China(2023YFH0041)。
文摘Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.
基金supported by the National Natural Science Foundation of China(31371680)the Beijing Food Crops Innovation Consortium Programthe China Agriculture Research System(CARS-11)
文摘A plastidic adenosine triphosphate（ATP）/adenosine diphosphate（ADP） transporter（AATP） is responsible for importing ATP from the cytosol into plastids. In dicotyledonous plants, increasing ATP supply is a potential way to facilitate anabolic synthesis in heterotrophic plastids. In this study, a gene encoding the AATP protein, named Ib AATP, was isolated from sweetpotato（Ipomoea batatas（L.） Lam.）. Transcripts of Ib AATP were predominantly detected in the storage roots and leaves and were induced by exogenous sucrose and subjected to circadian rhythm. Transient expression of Ib AATP in tobacco and onion epidermal cells revealed the plastidic localization of Ib AATP. The overexpression of Ib AATP in sweetpotato significantly increased the starch and amylose contents and led to enlarged starch granules. The IbA ATP-overexpressing plants showed altered fine structure of amylopectin, which contained an increased proportion of chains with a degree of polymerization（DP） of 10–23 and a reduced number of chains with a DP of 5–9 and 24–40. In addition, starch from the transgenic plants exhibited different pasting properties. The transcript levels of starch biosynthetic genes, including Ib AGP, Ib GBSSI, Ib SSIIV, and Ib SBE, were differentially regulated in the transgenic plants. These results revealed the explicit role of Ib AATP in the starch biosynthesis of sweetpotato and indicated that this gene has the potential to be used to improve starch content and quality in sweetpotato and other plants.
基金supported by the Malaysian Ministry of High Education and Universiti Teknologi Malaysia (UTM) under Tier 1 grant (No. Q.K130000.2543.12H95)
文摘A facile and green synthetic approach for fabrication of starch-stabilized magnetite nanoparticles was implemented at moderate temperature. This synthesis involved the use of iron salts, potato starch,sodium hydroxide and deionized water as iron precursors, stabilizer, reducing agent and solvent respectively. The nanoparticles（NPs） were characterized by UV-vis, PXRD, HR-TEM, FESEM, EDX, VSM and FT-IR spectroscopy. The ultrasonic assisted co-precipitation technique provides well formation of highly distributed starch/Fe3O4-NPs. Based on UV–vis analysis, the sample showed the characteristic of surface plasmon resonance in the presence of Fe3O4-NPs. The PXRD pattern depicted the characteristic of the cubic lattice structure of Fe3O4-NPs. HR-TEM analysis showed the good dispersion of NPs with a mean diameter and standard deviation of 10.68 4.207 nm. The d spacing measured from the lattice images were found to be around 0.30 nm and 0.52 nm attributed to the Fe3O4 and starch, respectively. FESEM analysis confirmed the formation of spherical starch/Fe3O4-NPs with the emission of elements of C, O and Fe by EDX analysis. The magnetic properties illustrated by VSM analysis indicated that the as synthesized sample has a saturation magnetization and coercivity of 5.30 emu/g and 22.898 G respectively.Additionally, the FTIR analysis confirmed the binding of starch with Fe3O4-NPs. This method was cost effective, facile and eco-friendly alternative for preparation of NPs.
基金financial support from the National Natural Science Foundation of China (31171547,31401651)
文摘Starch is the major component of wheat flour and serves as a multifunctional ingredient in food industry. The objective of the present study was to investigate starch granule size distribution of Chinese wheat cultivars, and to compare structure and functionality of starches in four leading cultivars Zhongmai 175, CA12092, Lunxuan 987, and Zhongyou 206. A wide variation in volume percentages of A- and B-type starch granules among genotypes was observed. Volume percentages of A- and B-type granules had ranges of 68.4–88.9% and 9.7–27.9% in the first cropping seasons, 74.1–90.1% and 7.2–25.3% in the second. Wheat cultivars with higher volume percentages of A- and B-type granules could serve as parents in breeding program for selecting high and low amylose wheat cultivars, respectively. In comparison with the B-type starch granules, the A-type granules starch showed difference in three aspects：（1） higher amount of ordered short-range structure and a lower relative crystallinity,（2） higher gelatinization onset（To） temperatures and enthalpies（ΔH）, and lower gelatinization conclusion temperatures（Tc）,（3） greater peak, though, and final viscosity, and lower breakdown viscosity and pasting temperature. It provides important information for breeders to develop potentially useful cultivars with particular functional properties of their starches suited to specific applications.
基金supported by the Earmarked Fund for CARS10-Sweetpotatothe 2115 Talent Development Program of China Agricultural University。
文摘Sweetpotato(Ipomoea batatas)starch is in high demand globally as a food and industrial product.However,the regulatory mechanisms governing starch biosynthesis and starch properties in this important crop remain largely unknown.Here we identified a natural allelic variant in the promoter of IbNAC22,encoding a NAC(NAM,ATAF1/2,and CUC2)transcription factor,which is closely linked to starch content in sweetpotato.In high-starch sweetpotato varieties,the T/C haplotype and a 13-bp deletion in the IbNAC22 promoter resulted in higher transcriptional activity.The high-starch IbNAC22 haplotype is more prevalent in regions of China where the sweetpotato starch industry is well developed,indicating that this advantageous allele type has been utilized in breeding starchy sweetpotato varieties in China.IbNAC22 is highly expressed in storage roots and starch-rich sweetpotato accessions.Overexpression of IbNAC22 significantly improved starch and amylose contents,as well as granule size and gelatinization temperature,and decreased starch crystallinity,whereas IbNAC22 knockdown had the opposite effects.IbNAC22 directly activates the expression of IbGBSSI,a key gene for amylose biosynthesis,but suppresses the expression of IbSBEI,a key gene for amylopectin biosynthesis.IbNAC22 directly interacts with IbNF-YA10.Overexpressing of IbNF-YA10 significantly improved starch and amylose contents,and starch gelatinization temperature,but decreased granule size,crystallinity,and amylopectin chain length distribution.IbNF-YA10 directly activates IbAGPL and IbGBSSI,which are key genes involved in starch and amylose biosynthesis.IbNAC22–IbNF-YA10 heterodimers further enhance the IbNF-YA10-induced activation of IbAGPL and IbGBSSI.These findings increase our understanding of starch biosynthesis and starch properties and provide strategies and candidate genes for the improvement of starchy root and tuber crops.
基金supported by an international collaboration project on wheat improvement from the Ministry of Agriculture of China (2006GR)
文摘Dumpling is one of the most important traditional wheat products in China. Dumpling quality is determined by the characteristics of both flour and filling, thus improvement of flour quality plays an important role in improving dumpling quality. Thirty-nine Shandong winter wheat cultivars and advanced lines sown in Jinan, Shandong Province, China, in the 2008-2009 cropping season were used to determine genetic variation in Chinese raw dumpling quality and its relationship with flour characteristics. Large variations were observed for protein quality parameters in comparison with starch properties. Variation in color of the raw dumpling sheet was broader than that of sensory evaluation parameters of boiled dumpling among tested wheat cultivars, indicating the large influence of filling on dumpling color. Two cultivars, Jimai 20 and Zimai 12, were identified as possessing very good quality of raw dumpling, and 21 cultivars and advanced lines showed good quality. Protein and total starch content influenced the L＊ value of raw dumpling sheets. L＂ value at 0 and 2 h after sheeting were significantly influenced by protein content （r=-0.46 and -0.52, P〈0.01） and total starch content （r=0.55 and 0.57, P〈0.01）, respectively. Flour yellow pigment was significantly corrected with a＊ （r=-0.67 and -0.62, P〈0.01） and b＊ （r=0.87 and 0.84, P〈0.01） value of raw dumpling sheets at 0 and 2 h after sheeting, respectively. Gluten strength parameters such as farinograph mixing tolerance index （MTI, r=-0.55, P〈0.01） were positively associated with appearance. MTI and energy were also significantly and positively correlated with elasticity of raw dumpling, with r=-0.54 and 0.47 （P〈0.01）. The positive relationships between peak viscosity （r=0.51, P〈0.01）, breakdown （r=0.54, P〈0.01）, and smoothness of raw dumpling were also observed. Therefore, it is suggested that breeding programs should give more attention to gluten strength and starch pasting parameters for raw dumpling quality improvement.
