Reduced starch granule number per chloroplast in the dpe2/phs1 mutant is dependent on initiation of starch degradation.

PubMed

Malinova, Irina; Fettke, Joerg

2017-01-01

An Arabidopsis double knock-out mutant lacking cytosolic disproportionating enzyme 2 (DPE2) and the plastidial phosphorylase (PHS1) revealed a dwarf-growth phenotype, reduced starch content, an uneven distribution of starch within the plant rosette, and a reduced number of starch granules per chloroplast under standard growth conditions. In contrast, the wild type contained 5-7 starch granules per chloroplast. Mature and old leaves of the double mutant were essentially starch free and showed plastidial disintegration. Several analyses revealed that the number of starch granules per chloroplast was affected by the dark phase. So far, it was unclear if it was the dark phase per se or starch degradation in the dark that was connected to the observed decrease in the number of starch granules per chloroplast. Therefore, in the background of the double mutant dpe2/phs1, a triple mutant was generated lacking the initial starch degrading enzyme glucan, water dikinase (GWD). The triple mutant showed improved plant growth, a starch-excess phenotype, and a homogeneous starch distribution. Furthermore, the number of starch granules per chloroplast was increased and was similar to wild type. However, starch granule morphology was only slightly affected by the lack of GWD as in the triple mutant and, like in dpe2/phs1, more spherical starch granules were observed. The characterized triple mutant was discussed in the context of the generation of starch granules and the formation of starch granule morphology.

Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch.

PubMed

Wokadala, Obiro Cuthbert; Emmambux, Naushad Mohammad; Ray, Suprakas Sinha

2014-11-04

In this study, waxy and high amylose starches were modified through butyl-etherification to facilitate compatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and wettability tests showed that hydrophobic butyl-etherified waxy and high amylose starches were obtained with degree of substitution values of 2.0 and 2.1, respectively. Differential scanning calorimetry, tensile testing, and scanning electron microscopy (SEM) demonstrated improved PLA/starch compatibility for both waxy and high amylose starch after butyl-etherification. The PLA/butyl-etherified waxy and high amylose starch composite films had higher tensile strength and elongation at break compared to PLA/non-butyl-etherified composite films. The morphological study using SEM showed that PLA/butyl-etherified waxy starch composites had a more homogenous microstructure compared to PLA/butyl-etherified high amylose starch composites. Thermogravimetric analysis showed that PLA/starch composite thermal stability decreased with starch butyl-etherification for both waxy and high amylose starches. This study mainly demonstrates that PLA/starch compatibility can be improved through starch butyl-etherification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preparation of acetylated waxy, normal, and high-amylose maize starches with intermediate degrees of substitution in aqueous solution and their properties.

PubMed

Luo, Zhi-Gang; Shi, Yong-Cheng

2012-09-19

Acetylated waxy, normal, and high-amylose maize starches with intermediate degrees of substitution (DS) were prepared in aqueous solution with 20% (w/w) sodium hydroxide as a catalyst. The level of DS was in the order high-amylose maize starch > waxy maize starch > normal maize starch. Settling volume indicated that during the early reaction, normal maize starch swelled to a lesser extent compared with waxy and high-amylose maize starches. The settling volume of all three starches increased initially but decreased after long reaction time. Aggregation of granules was observed as DS increased. The A-type X-ray diffraction pattern of acetylated normal and waxy maize starches weakened as DS increased, whereas the diffraction peaks disappeared in acetylated high-amylose starch when DS was 0.95. Low DS promoted the swelling of the starches in water, but at high DS, the starches became more hydrophobic and the peak viscosity of acetylated starches decreased.

Effects of citric acid esterification on digestibility, structural and physicochemical properties of cassava starch.

PubMed

Mei, Ji-Qiang; Zhou, Da-Nian; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

2015-11-15

In this study, citric acid was used to react with cassava starch in order to compare the digestibility, structural and physicochemical properties of citrate starch samples. The results indicated that citric acid esterification treatment significantly increased the content of resistant starch (RS) in starch samples. The swelling power and solubility of citrate starch samples were lower than those of native starch. Compared with native starch, a new peak at 1724 cm(-1) was appeared in all citrate starch samples, and crystalline peaks of all starch citrates became much smaller or even disappeared. Differential scanning calorimetry results indicated that the endothermic peak of citrate starches gradually shrank or even disappeared. Moreover, the citrate starch gels exhibited better freeze-thaw stability. These results suggested that citric acid esterification induced structural changes in cassava starch significantly affected its digestibility and it could be a potential method for the preparation of RS with thermal stability. Copyright © 2015 Elsevier Ltd. All rights reserved.

Insights into molecular structure and digestion rate of oat starch.

PubMed

Xu, Jinchuan; Kuang, Qirong; Wang, Kai; Zhou, Sumei; Wang, Shuo; Liu, Xingxun; Wang, Shujun

2017-04-01

The in vitro digestibility of oat starch and its relationship with starch molecular structure was investigated. The in vitro digestion results showed that the first-order kinetic constant (k) of oat starches (OS-1 and OS-2) was lower than that of rice starch. The size of amylose chains, amylose content and degree of branching (DB) of amylopectin in oat starch were significantly higher than the corresponding parameters in rice starch. The larger molecular size of oat starch may account for its lower digestion rate. The fine structure of amylopectin showed that oat starch had less chains of DP 6-12 and DP>36, which may explain the small difference in digestion rate between oat and rice starch. The biosynthesis model from oat amylopectin fine structure data suggested a lower starch branching enzyme (SBE) activity and/or a higher starch synthase (SS) activity, which may decrease the DB of oat starch and increase its digestion rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

Physicochemical properties of kiwifruit starch.

PubMed

Li, Dongxing; Zhu, Fan

2017-04-01

Three varieties of golden kiwifruit (Actinidia chinensis) (Gold3, Gold9 and Hort16A) were collected at the commercial harvesting time, and physicochemical properties of starches from core and outer pericarp were studied. Starch contents (dry weight basis) in outer pericarp and core tissues ranged from 38.6 to 51.8% and 34.6 to 40.7%, respectively. All the kiwifruit starches showed B-type polymorph. Compared to the outer pericarp starches, amylose content and enzyme susceptibility of core starches were higher, and the degree of crystallinity, granule size and gelatinization parameters of core starches were somewhat lower. This suggests different biosynthetic properties between these two starches. The enthalpy changes of gelatinization of outer pericarp starches were high (∼21J/g). Rheological properties of outer pericarp starches were compared with normal maize and potato starches showed high yield stress of flow properties. This study revealed the unique properties of kiwifruit starch among various types of starches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of waxy and normal potato starch remaining granules after chemical surface gelatinization: pasting behavior and surface morphology.

PubMed

Huang, Junrong; Chen, Zhenghong; Xu, Yalun; Li, Hongliang; Liu, Shuxing; Yang, Daqing; Schols, Henk A

2014-02-15

To understand the contribution of granule inner portion to the pasting property of starch, waxy potato starch and two normal potato starches and their acetylated starch samples were subjected to chemical surface gelatinization by 3.8 mol/L CaCl2 to obtain remaining granules. Native and acetylated, original and remaining granules of waxy potato starch had similar rapid visco analyzer (RVA) pasting profiles, while those of two normal potato starches behaved obviously different from each other. All remaining granules had lower peak viscosity than the corresponding original granules. Contribution of waxy potato starch granule's inner portion to the peak viscosity was significant more than those of normal potato starches. The shell structure appearing on the remaining granule surface for waxy potato starch was smoother and thinner than that for normal potato starches as observed by scanning electron microscopy, indicating a more regular structure of shell and a more ordered packing of shell for waxy potato starch granules. The blocklet size of waxy potato starch was smaller and more uniform than those of normal potato starches as shown by atomic force microscopy images of original and remaining granules. In general, our results provided the evidence for the spatial structure diversity between waxy and normal potato starch granules: outer layer and inner portion of waxy potato starch granule had similar structure, while outer layer had notably different structure from inner portion for normal potato starch granule. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Other Double Helix--The Fascinating Chemistry of Starch

NASA Astrophysics Data System (ADS)

Hancock, Robert D.; Tarbet, Bryon J.

2000-08-01

Current textbooks deal only briefly with the chemistry of starch. A short review with 21 references is presented, describing the structure of starch and indicating the double helix structure of A-type and B-type starch. The structure of the starch granule is examined, pointing out the existence of growth rings of alternating crystalline and noncrystalline starch, with growing amylopectin molecules extending from the hilum (point of origin) to the surface of the starch granule. The swelling of starch granules in water, above the gelatinization temperature of about 60 °C, is discussed. The process of gelatinization involves unraveling of the starch helix and a manyfold increase in volume of the starch granule as water is imbibed and bound to the unraveled starch polymer by hydrogen bonding. Baking bread or pastries causes unraveling of the starch helix, and the process by which these products become stale corresponds primarily to the re-forming of the starch helix. The importance of this phenomenon in food science is discussed. The absorption of nonpolar linear molecules such as I2, or linear nonpolar portions of molecules such as n-butanol or fats and phospholipids, by the C-type helix of starch is examined. The way in which starch is structurally modified to retard staling is discussed in relation to food technology.

The Simultaneous Abolition of Three Starch Hydrolases Blocks Transient Starch Breakdown in Arabidopsis*

PubMed Central

Streb, Sebastian; Eicke, Simona; Zeeman, Samuel C.

2012-01-01

In this study, we investigated which enzymes are involved in debranching amylopectin during transient starch degradation. Previous studies identified two debranching enzymes, isoamylase 3 (ISA3) and limit dextrinase (LDA), involved in this process. However, plants lacking both enzymes still degrade substantial amounts of starch. Thus, other enzymes/mechanisms must contribute to starch breakdown. We show that the chloroplastic α-amylase 3 (AMY3) also participates in starch degradation and provide evidence that all three enzymes can act directly at the starch granule surface. The isa3 mutant has a starch excess phenotype, reflecting impaired starch breakdown. In contrast, removal of AMY3, LDA, or both enzymes together has no impact on starch degradation. However, removal of AMY3 or LDA in addition to ISA3 enhances the starch excess phenotype. In plants lacking all three enzymes, starch breakdown is effectively blocked, and starch accumulates to the highest levels observed so far. This provides indirect evidence that the heteromultimeric debranching enzyme ISA1-ISA2 is not involved in starch breakdown. However, we illustrate that ISA1-ISA2 can hydrolyze small soluble branched glucans that accumulate when ISA3 and LDA are missing, albeit at a slow rate. Starch accumulation in the mutants correlates inversely with plant growth. PMID:23019330

Thermal properties of partially hydrolyzed starch-glycerophosphatidylcholine complexes with various acyl chains.

PubMed

Siswoyo, Tri Agus; Morita, Naofumi

2003-05-07

Complexes of starch and monoacyl-sn-glycerophosphatidylcholine (GPC) containing various acyl (myristoyl, palmitoyl, and stearoyl) chains were subjected to hydrolysis with glucoamylase (EC 3.2.1.3). The enzyme hydrolyzed approximately 40% of starch control and 20-28% of starch-GPC complexes. Among the GPCs examined, 1- and 2-monomyristoyl-sn-GPC showed the highest resistance to enzyme hydrolysis, and the hydrolysis rate of starch-GPCs was greater with longer chains. Enzymatic hydrolysis strongly affected the thermal properties of the starch. After enzymatic hydrolysis of starch-GPC complexes for 24 h, their thermograms had broader peaks with lower enthalpies than the corresponding starch without enzyme; however, the starch-GPC complexes showed little change. The surface of starch-GPC granules was less eroded. These results showed that the increasing amount of starch-GPC complexes could be more resistant to hydrolysis.

Effects of protein in wheat flour on retrogradation of wheat starch.

PubMed

Xijun, Lian; Junjie, Guo; Danli, Wang; Lin, Li; Jiaran, Zhu

2014-08-01

Albumins, globulins, gliadins, and glutenins were isolated from wheat flour and the effects of those proteins on retrogradation of wheat starch were investigated. The results showed that only glutenins retarded retrogradation of wheat starch and other 3 proteins promoted it. The results of IR spectra proved that no S-S linkage formed during retrogradation of wheat starch blended with wheat proteins. Combination of wheat starch and globulins or gliadins through glucosidic bonds hindered the hydrolysis of wheat starch by α-amylase. The melting peak temperatures of retrograded wheat starch attached to different proteins were 128.46, 126.14, 132.03, 121.65, and 134.84 °C for the control with no protein, albumins, glutenins, globulins, gliadins groups, respectively, and there was no second melting temperature for albumins group. Interaction of wheat proteins and starch in retrograded wheat starch greatly decreased the endothermic enthalpy (△H) of retrograded wheat starch. Retrograded wheat starch bound to gliadins might be a new kind of resistant starch based on glycosidic bond between starch and protein. © 2014 Institute of Food Technologists®

Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism

PubMed Central

Shaik, Shahnoor S.; Obata, Toshihiro; Hebelstrup, Kim H.; Schwahn, Kevin; Fernie, Alisdair R.; Mateiu, Ramona V.; Blennow, Andreas

2016-01-01

Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365

Starch phosphorylation in potato tubers is influenced by allelic variation in the genes encoding glucan water dikinase, starch branching enzymes I and II, and starch synthase III

PubMed Central

Carpenter, Margaret A.; Joyce, Nigel I.; Genet, Russell A.; Cooper, Rebecca D.; Murray, Sarah R.; Noble, Alasdair D.; Butler, Ruth C.; Timmerman-Vaughan, Gail M.

2015-01-01

Starch phosphorylation is an important aspect of plant metabolism due to its role in starch degradation. Moreover, the degree of phosphorylation of starch determines its physicochemical properties and is therefore relevant for industrial uses of starch. Currently, starch is chemically phosphorylated to increase viscosity and paste stability. Potato cultivars with elevated starch phosphorylation would make this process unnecessary, thereby bestowing economic and environmental benefits. Starch phosphorylation is a complex trait which has been previously shown by antisense gene repression to be influenced by a number of genes including those involved in starch synthesis and degradation. We have used an association mapping approach to discover genetic markers associated with the degree of starch phosphorylation. A diverse collection of 193 potato lines was grown in replicated field trials, and the levels of starch phosphorylation at the C6 and C3 positions of the glucosyl residues were determined by mass spectrometry of hydrolyzed starch from tubers. In addition, the potato lines were genotyped by amplicon sequencing and microsatellite analysis, focusing on candidate genes known to be involved in starch synthesis. As potato is an autotetraploid, genotyping included determination of allele dosage. Significant associations (p < 0.001) were found with SNPs in the glucan water dikinase (GWD), starch branching enzyme I (SBEI) and the starch synthase III (SSIII) genes, and with a SSR allele in the SBEII gene. SNPs in the GWD gene were associated with C6 phosphorylation, whereas polymorphisms in the SBEI and SBEII genes were associated with both C6 and C3 phosphorylation and the SNP in the SSIII gene was associated with C3 phosphorylation. These allelic variants have potential as genetic markers for starch phosphorylation in potato. PMID:25806042

Impact of dry heating on physicochemical properties of corn starch and lysine mixture.

PubMed

Ji, Ying; Yu, Jicheng; Xu, Yongbin; Zhang, Yinghui

2016-10-01

Corn starch was modified with lysine by dry heat treatment and to investigate how they can affect the pasting and structural properties of the treated starches. Dry heating with lysine reduced the pasting temperature and resulting in viscosity increase. The particle size of heated starch-lysine mixture increased, suggesting that starch granules were cross-linked to lysine. After dry heating, the onset temperature, peak temperature and conclusion temperature of corn starch-lysine mixture were lower than those of other starches. The degree of crystallinity decreased for the starch after dry heat treatment while these heated starch samples still have the same X-ray diffraction types as the original starch. Copyright © 2016 Elsevier B.V. All rights reserved.

Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics

PubMed Central

Xu, Xuan; Dechesne, Annemarie; Visser, Richard G. F.; Trindade, Luisa M.

2016-01-01

Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines. PMID:27911907

Digestibility of starches isolated from stem and root tubers of arracacha, cassava, cush-cush yam, potato and taro.

PubMed

Lovera, Mighay; Pérez, Elevina; Laurentin, Alexander

2017-11-15

Digestibility of arracacha, cassava, cush-cush yam, potato and taro starches was evaluated. In vitro (potentially-available starch and total resistant starch) and in vivo digestibility in the rice weevil (Sitophilus oryzae) bioassay (survival, weight variation, α-amylase like activity [ALA], and uric acid excretion [UAE] as biomarkers) were estimated. In in vitro assays, all starches presented high resistant starch content (14-56%, dry basis), except for cassava starch. In in vivo assays, cush-cush yam and potato starches promoted higher ALA (>3 times) and UAE (>4 times) compare to a reference diet (cornstarch), in agreement to their low digestibility. These two biomarkers were related with resistant starch (r>0.81) and could be used to predict the starch bioavailability. This study demonstrates that the use of both in vitro and in vivo assays allows a better evaluation of starch digestibility, and may help to elucidate the final metabolic fate of starch digestion products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Insights into the multi-scale structure and digestibility of heat-moisture treated rice starch.

PubMed

Wang, Hongwei; Liu, Yufan; Chen, Ling; Li, Xiaoxi; Wang, Jun; Xie, Fengwei

2018-03-01

The digestibility and structural changes of rice starch induced by heat-moisture treatment (HMT) were investigated, and the relationships among the moisture content-starch structure-starch digestibility were revealed. HMT could simultaneously disorder and reassemble the rice starch molecules across multi-scale lengths and convert some fractions of rapidly-digestible starch (RDS) into slowly-digestible starch (SDS) and resistant starch (RS). In particular, the HMT rice starch with less than 30% moisture content showed a higher SDS+RS content (25.0%). During HMT, SDS and RS were preferably formed by the degraded starch molecules with M w between 4×10 5 and 4×10 6 g/mol, single helices and amylose-lipids complexes that were formed by degraded starch chains with higher thermal stability and crystalline lamellae with greater thicknesses. Thus, our research suggests a potential approach using HMT to control the digestion of starch products with desired digestibility. Copyright © 2017. Published by Elsevier Ltd.

Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics.

PubMed

Xu, Xuan; Dechesne, Annemarie; Visser, Richard G F; Trindade, Luisa M

2016-01-01

Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines.

Impact of amylosucrase modification on the structural and physicochemical properties of native and acid-thinned waxy corn starch.

PubMed

Zhang, Hao; Zhou, Xing; He, Jian; Wang, Tao; Luo, Xiaohu; Wang, Li; Wang, Ren; Chen, Zhengxing

2017-04-01

Recombinant amylosucrase from Neisseria polysaccharea was utilized to modify native and acid-thinned starches. The molecular structures and physicochemical properties of modified starches were investigated. Acid-thinned starch displayed much lower viscosity after gelatinization than did the native starch. However, the enzyme exhibited similar catalytic efficiency for both forms of starch. The modified starches had higher proportions of long (DP>33) and intermediate chains (DP 13-33), and X-ray diffraction showed a B-type crystalline structure for all modified starches. With increasing reaction time, the relative crystallinity and endothermic enthalpy of the modified starches gradually decreased, whereas the melting peak temperatures and resistant starch contents increased. Slight differences were observed in thermal parameters, relative crystallinity, and branch chain length distribution between the modified native and acid-thinned starches. Moreover, the digestibility of the modified starches was not affected by acid hydrolysis pretreatment, but was affected by the percentage of intermediate and long chains. Copyright © 2016 Elsevier Ltd. All rights reserved.

Porous starch extracted from Chinese rice wine vinasse: characterization and adsorption properties.

PubMed

Li, Hongyan; Jiao, Aiquan; Wei, Benxi; Wang, Yong; Wu, Chunsen; Jin, Zhengyu; Tian, Yaoqi

2013-10-01

Chinese rice wine vinasse (the fermentation residue after removal of the crude wine or beer) contains 20-30% residual native starch. These starches are partly hydrolyzed by amylase and glucoamylase during rice wine fermentation, indicating that it is a potential source of porous starch, which is a value-added material. In the present study, morphological, short-range order, crystalline, and thermal studies were determined to characterize the structural and chemical properties of vinasse starch. The results showed that vinasse starch granule had a rough and porous shape and was much more ordered than native starch. Vinasse starch also could tolerate a higher temperature than native starch. The water and oil adsorptive capacities of vinasse starch were 1.89 and 4.14 times higher than that of native rice starch. These results suggest that vinasse is an effective and economical source of porous starch for using as adsorbent. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Effect of high pressure on rheological and thermal properties of quinoa and maize starches.

PubMed

Li, Guantian; Zhu, Fan

2018-02-15

Quinoa starch has small granules with relatively low gelatinization temperatures and amylose content. High hydrostatic pressure (HHP) is a non-thermal technique for food processing. In this study, effects of HHP up to 600MPa on physical properties of quinoa starch were studied and compared with those of a normal maize starch. Both starches gelatinized at 500 and 600MPa. The pressure of 600MPa completely gelatinized quinoa starch as revealed by thermal analysis. Dynamic rheological analysis showed that HHP improved the gel stability of both starches during cooling. HHP had little effects on amylopectin recrystallization and gel textural properties of starch. Overall, quinoa starch was more susceptible to HHP than maize starch. The effects of HHP on some rheological properties such as frequency dependence were different between these two types of starches. The differences could be attributed to the different composition, granular and chemical structures of starch, and the presence of granule remnants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical, morphological and functional properties of Brazilian jackfruit (Artocarpus heterophyllus L.) seeds starch.

PubMed

Madruga, Marta Suely; de Albuquerque, Fabíola Samara Medeiros; Silva, Izis Rafaela Alves; do Amaral, Deborah Silva; Magnani, Marciane; Queiroga Neto, Vicente

2014-01-15

Starches used in food industry are extracted from roots, tubers and cereals. Seeds of jackfruit are abundant and contain high amounts of starch. They are discarded during the fruit processing or consumption and can be an alternative source of starch. The starch was extract from the jackfruit seeds and characterised to chemical, morphological and functional properties. Soft and hard jackfruit seeds showed starch content of 92.8% and 94.5%, respectively. Starch granules showed round and bell shape and some irregular cuts on their surface with type-A crystallinity pattern, similar to cereals starches. The swelling power and solubility of jackfruit starch increased with increasing temperature, showing opaque pastes. The soft seeds starch showed initial and final gelatinisation temperature of 36°C and 56°C, respectively; while hard seeds starch presented initial gelatinisation at 40°C and final at 61°C. These results suggest that the Brazilian jackfruit seeds starches could be used in food products. Copyright © 2013 Elsevier Ltd. All rights reserved.

Mixture design of rice flour, maize starch and wheat starch for optimization of gluten free bread quality.

PubMed

Mancebo, Camino M; Merino, Cristina; Martínez, Mario M; Gómez, Manuel

2015-10-01

Gluten-free bread production requires gluten-free flours or starches. Rice flour and maize starch are two of the most commonly used raw materials. Over recent years, gluten-free wheat starch is available on the market. The aim of this research was to optimize mixtures of rice flour, maize starch and wheat starch using an experimental mixture design. For this purpose, dough rheology and its fermentation behaviour were studied. Quality bread parameters such as specific volume, texture, cell structure, colour and acceptability were also analysed. Generally, starch incorporation reduced G* and increased the bread specific volume and cell density, but the breads obtained were paler than the rice flour breads. Comparing the starches, wheat starch breads had better overall acceptability and had a greater volume than maize-starch bread. The highest value for sensorial acceptability corresponded to the bread produced with a mixture of rice flour (59 g/100 g) and wheat starch (41 g/100 g).

Effect on in vitro starch digestibility of Mexican blue maize anthocyanins.

PubMed

Camelo-Méndez, Gustavo A; Agama-Acevedo, Edith; Sanchez-Rivera, Mirna M; Bello-Pérez, Luis A

2016-11-15

The purpose of this study was to evaluate the effect of blue maize extracts obtained by acid-methanol treatment on the nutritional in vitro starch fractions such as: rapidly digestive starch (RDS), slowly digestive starch (SDS) and resistant starch (RS) of native and gelatinized commercial maize starch. Chromatographic analysis (HPLC-DAD/ESI-MS) of blue maize extracts showed the presence of seven anthocyanins, where cyanidin-3-(6″-malonylglucoside) was the main. Blue maize extracts modified nutritional in vitro starch fractions (decrease of RDS) while RS content increased (1.17 and 2.02 times for native and gelatinized commercial maize starch, respectively) when anthocyanins extracts were added to starch up to 75% (starch weight). This preliminary observation provides the basis for further suitability evaluation of blue maize extract as natural starch-modifier by the possible anthocyanins-starch interaction. Anthocyanin extracts can be a suitable to produce functional foods with higher RS content with potential human health benefits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Resistant starch type V formation in brown lentil (Lens culinaris Medikus) starch with different lipids/fatty acids.

PubMed

Okumus, Bahar Nur; Tacer-Caba, Zeynep; Kahraman, Kevser; Nilufer-Erdil, Dilara

2018-02-01

This study aimed to characterize the brown lentil (Lens culinaris Medikus) starch and investigate the formation of amylose-lipid complexes (Resistant Starch Type V) by the addition of different lipids/fatty acids (10%, w/w) to both raw and cooked starch samples. Resistant starch content (measured by the official method of AACCI (Method 32-40), using the resistant starch assay kit) of raw brown lentil starch (BLS) increased significantly by the additions of lipids/fatty acids, starch sample complexed with HSO (hydrogenated sunflower oil) (14.1±0.4%) being the highest. For the cooked starch/lipid complexes, more profound effect was evident (22.2-67.7%). Peak, breakdown and trough viscosity values of the amylose-lipid complexed starches were significantly lower than that of BLS (p<0.05), while significant decreases in the setback and final viscosities were only detected in oil samples, but not in fatty acids. Each lipid in concern exerted different effects on the digestibility of starch and amylose-lipid complex formation while having no substantial differential effects on the thermal properties of starch depicted by differential scanning calorimetry (DSC). Amylose-lipid complex formation with suitable fatty acids/lipids seems a promising way of increasing resistant starch content of food formulations. Although the applications being quite uncommon yet, brown lentil seems to have potential both as a starch and also as a resistant starch source. Copyright © 2017 Elsevier Ltd. All rights reserved.

Proteome Profile of Starch Granules Purified from Rice (Oryza sativa) Endosperm.

PubMed

Xing, Shihai; Meng, Xiaoxi; Zhou, Lihui; Mujahid, Hana; Zhao, Chunfang; Zhang, Yadong; Wang, Cailin; Peng, Zhaohua

2016-01-01

Starch is the most important food energy source in cereals. Many of the known enzymes involved in starch biosynthesis are partially or entirely granule-associated in the endosperm. Studying the proteome of rice starch granules is critical for us to further understand the mechanisms underlying starch biosynthesis and packaging of starch granules in rice amyloplasts, consequently for the improvement of rice grain quality. In this article, we developed a protocol to purify starch granules from mature rice endosperm and verified the quality of purified starch granules by microscopy observations, I2 staining, and Western blot analyses. In addition, we found the phenol extraction method was superior to Tris-HCl buffer extraction method with respect to the efficiency in recovery of starch granule associated proteins. LC-MS/MS analysis showed identification of already known starch granule associated proteins with high confidence. Several proteins reported to be involved in starch synthesis in prior genetic studies in plants were also shown to be enriched with starch granules, either directly or indirectly, in our studies. In addition, our results suggested that a few additional candidate proteins may also be involved in starch synthesis. Furthermore, our results indicated that some starch synthesis pathway proteins are subject to protein acetylation modification. GO analysis and KEGG pathway enrichment analysis showed that the identified proteins were mainly located in plastids and involved in carbohydrate metabolism. This study substantially advances the understanding of the starch granule associated proteome in rice and post translational regulation of some starch granule associated proteins.

Powder and compaction characteristics of pregelatinized starches.

PubMed

Rojas, J; Uribe, Y; Zuluaga, A

2012-06-01

Pregelatinized starch is widely used as a pharmaceutical aid, especially as a filler-binder. It is known that the tableting performance of excipients could be affected by their source. The aim of this study was to evaluate the powder and tableting properties of pregelatinized starches obtained from yucca, corn and rice and compare those properties with those of Starch 1500. This material had the lowest particle size, and porosity and largest density and best flow. However, yucca starch and corn starch showed an irregular granule morphology, better compactibility and compressibility than Starch 1500. Their onset of plastic deformation and their strain rate sensitivity was comparable to that of Starch 1500. These two materials showed compact disintegration slower that Starch 1500. Conversely, rice starch showed a high elasticity, and friability, low compactibility, which are undesirable for direct compression. This study demonstrated the potential use of pregelatinized starches, especially those obtained from yucca and corn as direct compression filler-binders.

Physicochemical properties of rhizome starch from a traditional Chinese medicinal plant of Anemone altaica.

PubMed

Man, Jianmin; Cai, Jinwen; Cai, Canhui; Huai, Huyin; Wei, Cunxu

2012-06-20

This study investigated the physicochemical properties of rhizome starch of A. altaica for the first time. The results were compared to those obtained from two common starches (potato and rice). The rhizome had a starch content of 49.8%. Isolated starch granules were mostly oval in shape with a central Maltese cross and an average long axis of 6.25 μm. The starch contained 35.5% amylose and had lower gelatinization and pasting temperatures than rice and potato starches and a swelling power comparable to potato. Altaica starch had high breakdown and setback viscosities. X-ray diffraction revealed B-type starch with relative degree of crystallinity of 17.5%. Starch possessed a high susceptibility to hydrolysis by acid, porcine pancreatic α-amylase and Aspergillus niger amyloglucosidase when compared with potato and rice starches. Copyright © 2012 Elsevier Ltd. All rights reserved.

Engineering Potato Starch with a Higher Phosphate Content

PubMed Central

Xu, Xuan; Huang, Xing-Feng; Visser, Richard G. F.

2017-01-01

Phosphate esters are responsible for valuable and unique functionalities of starch for industrial applications. Also in the cell phosphate esters play a role in starch metabolism, which so far has not been well characterized in storage starch. Laforin, a human enzyme composed of a carbohydrate-binding module and a dual-specificity phosphatase domain, is involved in the dephosphorylation of glycogen. To modify phosphate content and better understand starch (de)phosphorylation in storage starch, laforin was engineered and introduced into potato (cultivar Kardal). Interestingly, expression of an (engineered) laforin in potato resulted in significantly higher phosphate content of starch, and this result was confirmed in amylose-free potato genetic background (amf). Modified starches exhibited altered granule morphology and size compared to the control. About 20–30% of the transgenic lines of each series showed red-staining granules upon incubation with iodine, and contained higher phosphate content than the blue-stained starch granules. Moreover, low amylose content and altered gelatinization properties were observed in these red-stained starches. Principle component and correlation analysis disclosed a complex correlation between starch composition and starch physico-chemical properties. Ultimately, the expression level of endogenous genes involved in starch metabolism was analysed, revealing a compensatory response to the decrease of phosphate content in potato starch. This study provides a new perspective for engineering starch phosphate content in planta by making use of the compensatory mechanism in the plant itself. PMID:28056069

21 CFR 178.3520 - Industrial starch-modified.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Industrial starch-modified. 178.3520 Section 178... SANITIZERS Certain Adjuvants and Production Aids § 178.3520 Industrial starch-modified. Industrial starch... provisions of this section. (a) Industrial starch-modified is identified as follows: (1) A food starch...

21 CFR 178.3520 - Industrial starch-modified.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Industrial starch-modified. 178.3520 Section 178... SANITIZERS Certain Adjuvants and Production Aids § 178.3520 Industrial starch-modified. Industrial starch... provisions of this section. (a) Industrial starch-modified is identified as follows: (1) A food starch...

Rheological properties of reactive extrusion modified waxy starch and waxy starch-polyacrylamide copolymer gels

USDA-ARS?s Scientific Manuscript database

The rheological properties of modified waxy starch and waxy starch-polyacrylamide graft copolymers prepared by reactive extrusion were investigated. Both materials can absorb huge amount of water and form gels. The modified waxy starch and waxy starch-polyacrylamide graft copolymer gels all exhibite...

Effect of genotype and environment on the concentrations of starch and protein in, and the physicochemical properties of starch from, field pea and fababean.

PubMed

Hood-Niefer, Shannon D; Warkentin, Thomas D; Chibbar, Ravindra N; Vandenberg, Albert; Tyler, Robert T

2012-01-15

The effects of genotype and environment and their interaction on the concentrations of starch and protein in, and the amylose content and thermal and pasting properties of starch from, pea and fababean are not well known. Differences due to genotype were observed in the concentrations of starch and protein in pea and fababean, in the onset temperature (To) and peak temperature (Tp) of gelatinization of fababean starch, and in the pasting, trough, cooling and final viscosities of pea starch and fababean starch. Significant two-way interactions (location × genotype) were observed for the concentration of starch in fababean and the amylose content, To, endothermic enthalpy of gelatinization (ΔH) and trough viscosity of fababean starch. Significant three-way interactions (location × year × genotype) were observed for the concentration of starch in pea and the pasting, trough, cooling and final viscosities of pea starch. Differences observed in the concentrations of starch and protein in pea and fababean were sufficient to be of practical significance to end-users, but the relatively small differences in amylose content and physicochemical properties of starch from pea and fababean were not. Copyright © 2011 Society of Chemical Industry.

Multi-scale structures and pasting characteristics of starch in whole-wheat flour treated by superfine grinding.

PubMed

Niu, Meng; Zhang, Binjia; Jia, Caihua; Zhao, Siming

2017-11-01

The multi-scale structures and pasting properties of starch in WWF were investigated after superfine grinding. Five particle size distributions of WWF and their corresponding starch were obtained. The grinding process reduced the particle size of WWF and starch. However, a slight increase of fragments from starch granules was observed with enhanced grinding strength because of the small decrease in starch particle size and the existence of other WWF components that undertook some of shearing force and friction during grinding. A prominent reduction in starch crystallinity was resulted due to the destruction of crystalline structure by grinding. Small-angle X-ray scattering analyses indicated the disordering in starch semi-crystalline lamellae with thinner lamellae thickness. Additionally, the 13 C Nuclear Magnetic Resonance spectra demonstrated the alterations in starch chain conformation by varying peak areas of starch carbons (C1 and C4). Along with these structural changes, Starch pasting characteristics showed substantial variations, indicating decreased viscosities and higher pasting stability. The results suggest that the grinding treatments influenced the structures and pasting properties of starch even at a non-separated state, the changes in starch structures were related to the variations in starch gelatinization characteristics. Copyright © 2017 Elsevier B.V. All rights reserved.

Recrystallization characteristics of high hydrostatic pressure gelatinized normal and waxy corn starch.

PubMed

Li, Wenhao; Tian, Xiaoling; Wang, Peng; Saleh, Ahmed S M; Luo, Qingui; Zheng, Jianmei; Ouyang, Shaohui; Zhang, Guoquan

2016-02-01

High hydrostatic pressure (HHP) can lead to starch gelatinization at room temperature, while the retrogradation mechanism of HHP gelatinized starch is not well known. HHP gelatinized normal and waxy corn starches were stored at room temperature for 192 h in order to investigate the retrogradation characteristics. The scanning electron microscopy (SEM), polarised light microscopy and differential scanning calorimetric (DSC) analysis showed that the pressurization of normal and waxy corn starch suspensions with concentration of 30% (w/v) at 600 MPa for 15 min resulted in a complete gelatinization. In addition, the pressure-gelatinized normal and waxy corn starch gels were stored and subjected to X-ray diffraction (XRD) analysis, resistant starch content determination, swelling power and pasting behavior. The retrograded normal maize and waxy maize starch showed a substantial loss of A-type crystallinity. Both pressure-gelatinized normal and waxy corn starches showed an increase in resistant starch content and relative crystallinity degree with the increase of storage time. In addition, restricted starch swelling power and lower pasting viscosities were observed for these two retrograded starches. The amylose molecule within starch granules has been regarded as the main factor to affect the structural and physicochemical properties during the retrogradation process of HHP-gelatinized starch granules. Copyright © 2015 Elsevier B.V. All rights reserved.

Slowly digestible waxy maize starch prepared by octenyl succinic anhydride esterification and heat-moisture treatment: glycemic response and mechanism.

PubMed

He, Jinhua; Liu, Jie; Zhang, Genyi

2008-01-01

The mechanism and molecular structure of the slowly digestible waxy maize starch prepared by octenyl succinic anhydride (OSA) esterification and heat-moisture treatment were investigated. The in vitro Englyst test showed a proportion of 28.3% slowly digestible starch (SDS) when waxy maize starch was esterified with 3% OSA (starch weight based, and it is named OSA-starch), and a highest SDS content of 42.8% was obtained after OSA-starch (10% moisture) was further heated at 120 degrees C for 4 h (named HOSA-starch). The in vivo glycemic response of HOSA-starch, which showed a delayed appearance of blood glucose peak and a significant reduction (32.2%) of the peak glucose concentration, further confirmed its slow digestion property. Amylopectin debranching analysis revealed HOSA-starch had the highest resistance to debranching enzymes of isoamylase and pullulanase, and a simultaneous decrease of K m and V m (enzyme kinetics) was also shown when HOSA-starch was digested by either alpha-amylase or amyloglucosidase, indicating that the slow digestion of HOSA-starch resulted from an uncompetitive inhibition of enzyme activity during digestion. Size exclusion chromatography analysis of HOSA-starch showed fragmented amylopectin molecules with more nonreducing ends that are favorable for RS conversion to SDS by the action of amyloglucosidase in the Englyst test. Further solubility analysis indicates that the water-insolubility of HOSA-starch is caused by OSA-mediated cross-linking of amylopectin and the hydrophobic interaction between OSA-modified starch molecules. The water-insolubility of HOSA-starch would decrease its enzyme accessibility, and the digestion products with attached OSA molecules might also directly act as the uncompetitive inhibitor to reduce the enzyme activity leading to a slow digestion of HOSA-starch.

Improved Starch Digestion of Sucrase-deficient Shrews Treated With Oral Glucoamylase Enzyme Supplements.

PubMed

Nichols, Buford L; Avery, Stephen E; Quezada-Calvillo, Roberto; Kilani, Shadi B; Lin, Amy Hui-Mei; Burrin, Douglas G; Hodges, Benjamin E; Chacko, Shaji K; Opekun, Antone R; Hindawy, Marwa El; Hamaker, Bruce R; Oda, Sen-Ichi

2017-08-01

Although named because of its sucrose hydrolytic activity, this mucosal enzyme plays a leading role in starch digestion because of its maltase and glucoamylase activities. Sucrase-deficient mutant shrews, Suncus murinus, were used as a model to investigate starch digestion in patients with congenital sucrase-isomaltase deficiency.Starch digestion is much more complex than sucrose digestion. Six enzyme activities, 2 α-amylases (Amy), and 4 mucosal α-glucosidases (maltases), including maltase-glucoamylase (Mgam) and sucrase-isomaltase (Si) subunit activities, are needed to digest starch to absorbable free glucose. Amy breaks down insoluble starch to soluble dextrins; mucosal Mgam and Si can either directly digest starch to glucose or convert the post-α-amylolytic dextrins to glucose. Starch digestion is reduced because of sucrase deficiency and oral glucoamylase enzyme supplement can correct the starch maldigestion. The aim of the present study was to measure glucogenesis in suc/suc shrews after feeding of starch and improvement of glucogenesis by oral glucoamylase supplements. Sucrase mutant (suc/suc) and heterozygous (+/suc) shrews were fed with C-enriched starch diets. Glucogenesis derived from starch was measured as blood C-glucose enrichment and oral recombinant C-terminal Mgam glucoamylase (M20) was supplemented to improve starch digestion. After feedings, suc/suc and +/suc shrews had different starch digestions as shown by blood glucose enrichment and the suc/suc had lower total glucose concentrations. Oral supplements of glucoamylase increased suc/suc total blood glucose and quantitative starch digestion to glucose. Sucrase deficiency, in this model of congenital sucrase-isomaltase deficiency, reduces blood glucose response to starch feeding. Supplementing the diet with oral recombinant glucoamylase significantly improved starch digestion in the sucrase-deficient shrew.

Resistant starch intakes in the United States.

PubMed

Murphy, Mary M; Douglass, Judith Spungen; Birkett, Anne

2008-01-01

Dietary fiber represents a broad class of undigested carbohydrate components. The components vary in chemical and physical nature and in their physiological outcomes. Resistant starch is starch that escapes digestion in the small intestine and that may be fermented in the large intestine. The purpose of this study was to estimate consumption of resistant starch by the US population and to identify key sources of dietary resistant starch. A database of resistant starch concentrations in foods was developed from the publicly available literature. These concentrations were linked to foods reported in 24-hour dietary recalls from participants in the 1999-2002 National Health and Nutrition Examination Surveys and estimates of resistant starch intakes were generated. The study population included 18,305 nonbreastfeeding individuals in the United States. The dietary intake of resistant starch was determined for 10 US subpopulations defined by age, sex, and race/ethnicity. Three estimates of resistant starch intake were made for each person based on the minimum, mean, and maximum concentrations of resistant starch in the foods consumed. Americans aged 1 year and older were estimated to consume approximately 4.9 g resistant starch per day based on mean resistant starch concentrations (range 2.8 to 7.9 g resistant starch per day). Breads, cooked cereals/pastas, and vegetables (other than legumes) contributed 21%, 19%, and 19% of total resistant starch intake, respectively, and were top sources of resistant starch. Findings from this study suggest that the estimated intake of resistant starch by Americans is approximately 3 to 8 g per person per day. These estimates of resistant starch intake provide a valuable reference for researchers and food and nutrition professionals and will allow for more accurate estimates of total intakes of carbohydrate compounds that escape digestion in the small intestine.

In vitro utilization of amylopectin and high-amylose maize (Amylomaize) starch granules by human colonic bacteria.

PubMed

Wang, X; Conway, P L; Brown, I L; Evans, A J

1999-11-01

It has been well established that a certain amount of ingested starch can escape digestion in the human small intestine and consequently enters the large intestine, where it may serve as a carbon source for bacterial fermentation. Thirty-eight types of human colonic bacteria were screened for their capacity to utilize soluble starch, gelatinized amylopectin maize starch, and high-amylose maize starch granules by measuring the clear zones on starch agar plates. The six cultures which produced clear zones on amylopectin maize starch- containing plates were selected for further studies for utilization of amylopectin maize starch and high-amylose maize starch granules A (amylose; Sigma) and B (Culture Pro 958N). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to detect bacterial starch-degrading enzymes. It was demonstrated that Bifidobacterium spp., Bacteroides spp., Fusobacterium spp., and strains of Eubacterium, Clostridium, Streptococcus, and Propionibacterium could hydrolyze the gelatinized amylopectin maize starch, while only Bifidobacterium spp. and Clostridium butyricum could efficiently utilize high-amylose maize starch granules. In fact, C. butyricum and Bifidobacterium spp. had higher specific growth rates in the autoclaved medium containing high-amylose maize starch granules and hydrolyzed 80 and 40% of the amylose, respectively. Starch-degrading enzymes were cell bound on Bifidobacterium and Bacteroides cells and were extracellular for C. butyricum. Active staining for starch-degrading enzymes on SDS-PAGE gels showed that the Bifidobacterium cells produced several starch-degrading enzymes with high relative molecular (M(r)) weights (>160,000), medium-sized relative molecular weights (>66,000), and low relative molecular weights (<66,000). It was concluded that Bifidobacterium spp. and C. butyricum degraded and utilized granules of amylomaize starch.

In Vitro Utilization of Amylopectin and High-Amylose Maize (Amylomaize) Starch Granules by Human Colonic Bacteria

PubMed Central

Wang, Xin; Conway, Patricia Lynne; Brown, Ian Lewis; Evans, Anthony John

1999-01-01

It has been well established that a certain amount of ingested starch can escape digestion in the human small intestine and consequently enters the large intestine, where it may serve as a carbon source for bacterial fermentation. Thirty-eight types of human colonic bacteria were screened for their capacity to utilize soluble starch, gelatinized amylopectin maize starch, and high-amylose maize starch granules by measuring the clear zones on starch agar plates. The six cultures which produced clear zones on amylopectin maize starch- containing plates were selected for further studies for utilization of amylopectin maize starch and high-amylose maize starch granules A (amylose; Sigma) and B (Culture Pro 958N). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to detect bacterial starch-degrading enzymes. It was demonstrated that Bifidobacterium spp., Bacteroides spp., Fusobacterium spp., and strains of Eubacterium, Clostridium, Streptococcus, and Propionibacterium could hydrolyze the gelatinized amylopectin maize starch, while only Bifidobacterium spp. and Clostridium butyricum could efficiently utilize high-amylose maize starch granules. In fact, C. butyricum and Bifidobacterium spp. had higher specific growth rates in the autoclaved medium containing high-amylose maize starch granules and hydrolyzed 80 and 40% of the amylose, respectively. Starch-degrading enzymes were cell bound on Bifidobacterium and Bacteroides cells and were extracellular for C. butyricum. Active staining for starch-degrading enzymes on SDS-PAGE gels showed that the Bifidobacterium cells produced several starch-degrading enzymes with high relative molecular (Mr) weights (>160,000), medium-sized relative molecular weights (>66,000), and low relative molecular weights (<66,000). It was concluded that Bifidobacterium spp. and C. butyricum degraded and utilized granules of amylomaize starch. PMID:10543795

Preparation of calcium- and magnesium-fortified potato starches with altered pasting properties.

PubMed

Noda, Takahiro; Takigawa, Shigenobu; Matsuura-Endo, Chie; Ishiguro, Koji; Nagasawa, Koichi; Jinno, Masahiro

2014-09-15

Calcium- and magnesium-fortified potato starches were prepared by immersion in various concentrations of CaCl2 and MgCl2 aqueous solutions, respectively. The pasting properties, i.e., peak viscosity and breakdown, of all the starches obtained above were analyzed using a Rapid Visco Analyzer. Furthermore, the gelatinization properties and in vitro digestibility of the representative calcium- and magnesium-fortified starches were tested. The maximum calcium content of the fortified potato starches was as high as 686 ppm with the addition of a high-concentration CaCl2 solution, while the calcium content of the control potato starch was 99 ppm. The magnesium content increased from 89 to 421 ppm by treatment of the potato starch with an MgCl2 solution. Markedly lower values of peak viscosity and breakdown were observed in calcium- and magnesium-fortified potato starches than in the control potato starch. However, the gelatinization temperature and enthalpy as well as resistant starch content of calcium- and magnesium-fortified potato starches were similar to those of the control potato starch. It is concluded that potato starches with altered pasting properties can be easily manufactured by the use of solutions containing high levels of calcium and magnesium.

Starch-Branching Enzymes Preferentially Associated with A-Type Starch Granules in Wheat Endosperm1

PubMed Central

Peng, Mingsheng; Gao, Ming; Båga, Monica; Hucl, Pierre; Chibbar, Ravindra N.

2000-01-01

Two starch granule-bound proteins (SGP), SGP-140 and SGP-145, were preferentially associated with A-type starch granules (>10 μm) in developing and mature wheat (Triticum aestivum) kernels. Immunoblotting and N-terminal sequencing suggested that the two proteins were different variants of SBEIc, a 152-kD isoform of wheat starch-branching enzyme. Both SGP-140 and SGP-145 were localized to the endosperm starch granules but were not found in the endosperm soluble fraction or pericarp starch granules younger than 15 d post anthesis (DPA). Small-size starch granules (<10 μm) initiated before 15 DPA incorporated SGP-140 and SGP-145 throughout endosperm development and grew into full-size A-type starch granules (>10 μm). In contrast, small-size starch granules harvested after 15 DPA contained only low amounts of SGP-140 and SGP-145 and developed mainly into B-type starch granules (<10 μm). Polypeptides of similar mass and immunologically related to SGP-140 and/or SGP-145 were also preferentially incorporated into A-type starch granules of barley (Hordeum vulgare), rye (Secale cereale), and triticale (× Triticosecale Wittmack) endosperm, which like wheat endosperm have a bimodal starch granule size distribution. PMID:10982441

Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate.

PubMed

Yang, Zhi; Swedlund, Peter; Gu, Qinfen; Hemar, Yacine; Chaieb, Sahraoui

2016-01-01

High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed.

Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate

PubMed Central

Yang, Zhi; Swedlund, Peter; Gu, Qinfen; Hemar, Yacine; Chaieb, Sahraoui

2016-01-01

High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed. PMID:27219066

Effects of pigeon pea and plantain starches on the compressional, mechanical, and disintegration properties of paracetamol tablets.

PubMed

Dare, Kunle; Akin-Ajani, Dorothy O; Odeku, Oluwatoyin A; Itiola, Oludele A; Odusote, Omotunde M

2006-03-01

A study has been made of the effects of pigeon pea starch obtained from the plant Cajanus cajan (L) Millisp. (family Fabaceae) and plantain starch obtained from the unripe fruit of Musa paradisiaca L. (family Musaceae) on the compressional, mechanical, and disintegration properties of paracetamol tablets in comparison with official corn starch BP. Analysis of compressional properties was done by using density measurements, and the Heckel and Kawakita equations, whereas the mechanical properties of the tablets were evaluated by using tensile strength (T--a measure of bond strength) and brittle fracture index (BFI--a measure of lamination tendency). The ranking for the mean yield pressure, P(y), for the formulations containing the different starches was generally corn < pigeon pea < plantain starch while the ranking for P(k), an inverse measure of the amount of plasticity, was pigeon pea < plantain < corn starch, which indicated that formulations containing corn starch generally exhibited the fastest onset of plastic deformation, whereas those formulations containing pigeon pea starch exhibited the highest amount of plastic deformation during tableting. The tensile strength of the tablets increased with increase in concentration of the starches while the Brittle Fracture Index decreased. The ranking for T was pigeon pea > plantain > corn starch while the ranking for BFI was corn > plantain > pigeon pea starch. The bonding capacity of the formulations was in general agreement with the tensile strength results. The disintegration time (DT) of the formulation increased with concentration of plantain and corn starches but decreased with concentration of pigeon pea starch. The general ranking of DT values was plantain < pigeon pea < corn starch. Notably, formulations containing pigeon pea starch exhibited the highest bond strength and lowest brittleness, suggesting the usefulness of pigeon pea starch in producing strong tablets with minimal lamination tendency. Plantain starch, on the other hand, would be more useful where faster disintegration of tablet is desired. The results show that the starches could be useful in various formulations depending on the intended use of the tablets with the implication that the experimental starches can be developed for commercial purposes.

Proteome Profile of Starch Granules Purified from Rice (Oryza sativa) Endosperm

PubMed Central

Xing, Shihai; Meng, Xiaoxi; Zhou, Lihui; Mujahid, Hana; Zhao, Chunfang; Zhang, Yadong; Wang, Cailin; Peng, Zhaohua

2016-01-01

Starch is the most important food energy source in cereals. Many of the known enzymes involved in starch biosynthesis are partially or entirely granule-associated in the endosperm. Studying the proteome of rice starch granules is critical for us to further understand the mechanisms underlying starch biosynthesis and packaging of starch granules in rice amyloplasts, consequently for the improvement of rice grain quality. In this article, we developed a protocol to purify starch granules from mature rice endosperm and verified the quality of purified starch granules by microscopy observations, I2 staining, and Western blot analyses. In addition, we found the phenol extraction method was superior to Tris-HCl buffer extraction method with respect to the efficiency in recovery of starch granule associated proteins. LC-MS/MS analysis showed identification of already known starch granule associated proteins with high confidence. Several proteins reported to be involved in starch synthesis in prior genetic studies in plants were also shown to be enriched with starch granules, either directly or indirectly, in our studies. In addition, our results suggested that a few additional candidate proteins may also be involved in starch synthesis. Furthermore, our results indicated that some starch synthesis pathway proteins are subject to protein acetylation modification. GO analysis and KEGG pathway enrichment analysis showed that the identified proteins were mainly located in plastids and involved in carbohydrate metabolism. This study substantially advances the understanding of the starch granule associated proteome in rice and post translational regulation of some starch granule associated proteins. PMID:27992503

Properties of foam and composite materials made o starch and cellulose fiber

USDA-ARS?s Scientific Manuscript database

Composite materials were made of starch and cellulose fibers. Pre-gelatinized starch was effective in dispersing pulp fiber in a starch matrix to form a viscous starch/fiber dough. The starch/fiber dough was a useful feedstock for various composite foam and plastic materials. Viscous blends of star...

Resistant starch: promise for improving human health.

PubMed

Birt, Diane F; Boylston, Terri; Hendrich, Suzanne; Jane, Jay-Lin; Hollis, James; Li, Li; McClelland, John; Moore, Samuel; Phillips, Gregory J; Rowling, Matthew; Schalinske, Kevin; Scott, M Paul; Whitley, Elizabeth M

2013-11-01

Ongoing research to develop digestion-resistant starch for human health promotion integrates the disciplines of starch chemistry, agronomy, analytical chemistry, food science, nutrition, pathology, and microbiology. The objectives of this research include identifying components of starch structure that confer digestion resistance, developing novel plants and starches, and modifying foods to incorporate these starches. Furthermore, recent and ongoing studies address the impact of digestion-resistant starches on the prevention and control of chronic human diseases, including diabetes, colon cancer, and obesity. This review provides a transdisciplinary overview of this field, including a description of types of resistant starches; factors in plants that affect digestion resistance; methods for starch analysis; challenges in developing food products with resistant starches; mammalian intestinal and gut bacterial metabolism; potential effects on gut microbiota; and impacts and mechanisms for the prevention and control of colon cancer, diabetes, and obesity. Although this has been an active area of research and considerable progress has been made, many questions regarding how to best use digestion-resistant starches in human diets for disease prevention must be answered before the full potential of resistant starches can be realized.

Resistant Starch: Promise for Improving Human Health12

PubMed Central

Birt, Diane F.; Boylston, Terri; Hendrich, Suzanne; Jane, Jay-Lin; Hollis, James; Li, Li; McClelland, John; Moore, Samuel; Phillips, Gregory J.; Rowling, Matthew; Schalinske, Kevin; Scott, M. Paul; Whitley, Elizabeth M.

2013-01-01

Ongoing research to develop digestion-resistant starch for human health promotion integrates the disciplines of starch chemistry, agronomy, analytical chemistry, food science, nutrition, pathology, and microbiology. The objectives of this research include identifying components of starch structure that confer digestion resistance, developing novel plants and starches, and modifying foods to incorporate these starches. Furthermore, recent and ongoing studies address the impact of digestion-resistant starches on the prevention and control of chronic human diseases, including diabetes, colon cancer, and obesity. This review provides a transdisciplinary overview of this field, including a description of types of resistant starches; factors in plants that affect digestion resistance; methods for starch analysis; challenges in developing food products with resistant starches; mammalian intestinal and gut bacterial metabolism; potential effects on gut microbiota; and impacts and mechanisms for the prevention and control of colon cancer, diabetes, and obesity. Although this has been an active area of research and considerable progress has been made, many questions regarding how to best use digestion-resistant starches in human diets for disease prevention must be answered before the full potential of resistant starches can be realized. PMID:24228189

Polymeric tannins significantly alter properties and in vitro digestibility of partially gelatinized intact starch granule.

PubMed

Amoako, Derrick B; Awika, Joseph M

2016-10-01

Excess calorie intake is a growing global problem. This study investigated effect of complexing partially gelatinized starch with condensed tannins on in vitro starch digestibility. Extracts from tannin and non-tannin sorghum, and cellulose control, were reacted with normal and waxy maize starch in 30% (30E) and 50% ethanol (50E) solutions at 70°C/20min. More tannins complexed with the 30E than 50E starches (mean 6.2 vs 3.5mg/g, respectively). In the 30E treatments, tannins significantly increased crystallinity, pasting temperature, peak viscosity, and slow digesting starch (from 100 to 274mg/g) in normal, but not waxy starch, suggesting intragranular cross-linking with amylose. Tannins doubled resistant starch (RS) to approx. 300mg/g in both starches. In 50E treatments, tannins made both maize starches behave like raw potato starch (>90% RS), suggesting granule surface interactions dominated. Non-tannin treatments generally behaved similar to cellulose. Condensed tannins could be used to favorably alter starch digestion profile. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecular disassembly of rice and lotus starches during thermal processing and its effect on starch digestibility.

PubMed

Wang, Shujun; Sun, Yue; Wang, Jinrong; Wang, Shuo; Copeland, Les

2016-02-01

The molecular disassembly of starch during thermal processing is a major determinant for the susceptibility of starch to enzymatic digestion. In the present study, the effects of thermal processing on the disassembly of the granular structure and the in vitro enzymatic digestibility of rice and lotus starches were investigated. After heating at 50 °C, rice and lotus starches did not show significant changes in granular morphology, long-range crystallinity and short-range molecular order. As the temperature increased to 60 °C, rice starch underwent a partial gelatinization followed by an incomplete disruption of granular morphology, crystallites and molecular order. In contrast, lotus starch was almost completely gelatinized at 60 °C. At 70 °C or higher, both starches were fully gelatinized with complete disruption of the micro and macro structures. Our results show that gelatinization greatly increased the in vitro enzymatic digestibility of both starches, but that the degree of disassembly of the starch structure during thermal processing was not a major determinant of the digestibility of gelatinized starch.

Performance of high amylose starch-composited gelatin films influenced by gelatinization and concentration.

PubMed

Wang, Wenhang; Wang, Kun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana; Liu, Anjun

2017-01-01

In order to study the impact of starch in film performance, high amylose corn starch was composited in gelatin films under different gelatinization conditions and, in high and low concentrations (10 and 50wt.%). It was found that hot water gelatinized starch (Gel-Shw) increased film mechanical strength and was dependent upon the starch concentration. The addition of an alkali component to the starch significantly enhanced the swelling of the starch granules and expedited the gelatinization process. Incorporation of starch, especially the alkalized starch (Sha), into the gelatin films decreased film solubility which improved its water resistance and water vapor permeability (WVP). Multiple techniques (DSC, TGA, FT-IR, and XRD) were used to characterize the process and results, including the crosslinking of the dissolved starch molecules and the particles formed from gelatinized starch during retrogradation process, which played an important role in improving the thermal stability of the composited gelatin films. Overall, the starch-gelatin composition provides a potential approach to improve gelatin film performance and benefit its applications in the food industry. Copyright © 2016 Elsevier B.V. All rights reserved.

Novel FT-IR Microspectroscopic Census of Simple Starch Granules for Octenyl Succinate Ester Modification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bai, Y.; Shi, Y; Wetzel, D

Fourier transform infrared (FT-IR) microspectroscopy was used to investigate reaction homogeneity of octenyl succinic anhydride modification on waxy maize starch and detect uniformity of blends of modified and native starches. For the first time, the level and uniformity of chemical substitution on individual starch granules were analyzed by FT-IR microspectroscopy. More than 100 starch granules of each sample were analyzed one by one by FT-IR microspectroscopy. In comparison to the native starch, modified starch had two additional bands at 1723 and 1563 cm{sup -1}, indicative of ester formation in the modified starch. For the 3% modification level, the degree ofmore » substitution (DS) was low (0.019) and the distribution of the ester group was not uniform among starch granules. For the modified starch with DS of 0.073, 99% of individual starch granules had a large carbonyl band area, indicating that most granules were modified to a sufficient extent that the presence of their carbonyl ester classified them individually as being modified. However, the octenyl succinate concentration varied between granules, suggesting that the reaction was not uniform. When modified starch (DS = 0.073) was blended with native starch (3:7, w/w) to achieve a mixture with an average DS of 0.019, FT-IR microspectroscopy was able to detect heterogeneity of octenyl succinate in the blend and determine the ratio of the modified starch to the native starch granules.« less

Flocculation and coalescence of droplets in oil-in-water emulsions formed with highly hydrolysed whey proteins as influenced by starch.

PubMed

Ye, Aiqian; Hemar, Yacine; Singh, Harjinder

2004-10-10

The effects of added unmodified amylopectin starch, modified amylopectin starch and amylose starch on the formation and properties of emulsions (4 wt.% corn oil) made with an extensively hydrolysed commercial whey protein (WPH) product under a range of conditions were examined. The rate of coalescence was calculated based on the changes in the droplet size of the emulsions during storage at 20 degrees C. The rates of creaming and coalescence in emulsions containing amylopectin starches were enhanced with increasing concentration of the starches during storage for up to 7 days. At a given starch concentration, the rate of coalescence was higher in the emulsions containing modified amylopectin starch than in those containing unmodified amylopectin starch, whereas it was lowest in the emulsions containing amylose starch. All emulsions containing unmodified and modified amylopectin starches showed flocculation of oil droplets by a depletion mechanism. However, flocculation was not observed in the emulsions containing amylose starch. The extent of flocculation was considered to correlate with the rate of coalescence of oil droplets. The different rates of coalescence could be explained on the basis of the strength of the depletion potential, which was dependent on the molecular weight and the radius of gyration of the starches. At high levels of starch addition (>1.5%), the rate of coalescence decreased gradually, apparently because of the high viscosity of the aqueous phase caused by the starch.

Physicochemical, digestibility and structural characteristics of starch isolated from banana cultivars.

PubMed

Agama-Acevedo, Edith; Nuñez-Santiago, Maria C; Alvarez-Ramirez, José; Bello-Pérez, Luis A

2015-06-25

Banana starches from diverse varieties (Macho, Morado, Valery and Enano Gigante) were studied in their physicochemical, structural and digestibility features. X-ray diffraction indicated that the banana starches present a B-type crystallinity pattern, with slight difference in the crystallinity level. Macho and Enano Gigante starches showed the highest pasting temperatures (79 and 78°C, respectively), whilst Valery and Morado varieties presented a slight breakdown and higher setback than the formers. Morado starch presented the highest solubility value and Valery starch the lowest one. The swelling pattern of the banana starches was in agreement with their pasting profile. All banana starches showed a shear-thinning profile. The resistant starch (RS) fraction was the main fraction in the uncooked banana starches. Morado variety showed the highest amount of slowly digestible starch (SDS) and the lowest RS content reported until now in banana starches. Banana starch cooked samples presented an important amount of SDS and RS. Molecular weight and gyration radius of the four banana starches ranged between 2.88-3.14×10(8)g/mol and 286-302nm, respectively. The chain-length distributions of banana amylopectin showed that B1 chains (DP 13-24) is the main fraction, and an important amount of long chains (DP≥37) are present. The information generated from this study can be useful to determine banana varieties for starch isolation with specific functionality. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparative Transcriptome Analysis Reveals Critical Function of Sucrose Metabolism Related-Enzymes in Starch Accumulation in the Storage Root of Sweet Potato

PubMed Central

Zhang, Kai; Wu, Zhengdan; Tang, Daobin; Luo, Kai; Lu, Huixiang; Liu, Yingying; Dong, Jie; Wang, Xin; Lv, Changwen; Wang, Jichun; Lu, Kun

2017-01-01

The starch properties of the storage root (SR) affect the quality of sweet potato (Ipomoea batatas (L.) Lam.). Although numerous studies have analyzed the accumulation and properties of starch in sweet potato SRs, the transcriptomic variation associated with starch properties in SR has not been quantified. In this study, we measured the starch and sugar contents and analyzed the transcriptome profiles of SRs harvested from sweet potatoes with high, medium, and extremely low starch contents, at five developmental stages [65, 80, 95, 110, and 125 days after transplanting (DAP)]. We found that differences in both water content and starch accumulation in the dry matter affect the starch content of SRs in different sweet potato genotypes. Based on transcriptome sequencing data, we assembled 112336 unigenes, and identified several differentially expressed genes (DEGs) involved in starch and sucrose metabolism, and revealed the transcriptional regulatory network controlling starch and sucrose metabolism in sweet potato SRs. Correlation analysis between expression patterns and starch and sugar contents suggested that the sugar–starch conversion steps catalyzed by sucrose synthase (SuSy) and UDP-glucose pyrophosphorylase (UGPase) may be essential for starch accumulation in the dry matter of SRs, and IbβFRUCT2, a vacuolar acid invertase, might also be a key regulator of starch content in the SRs. Our results provide valuable resources for future investigations aimed at deciphering the molecular mechanisms determining the starch properties of sweet potato SRs. PMID:28690616

Genome-wide analysis of starch metabolism genes in potato (Solanum tuberosum L.).

PubMed

Van Harsselaar, Jessica K; Lorenz, Julia; Senning, Melanie; Sonnewald, Uwe; Sonnewald, Sophia

2017-01-05

Starch is the principle constituent of potato tubers and is of considerable importance for food and non-food applications. Its metabolism has been subject of extensive research over the past decades. Despite its importance, a description of the complete inventory of genes involved in starch metabolism and their genome organization in potato plants is still missing. Moreover, mechanisms regulating the expression of starch genes in leaves and tubers remain elusive with regard to differences between transitory and storage starch metabolism, respectively. This study aimed at identifying and mapping the complete set of potato starch genes, and to study their expression pattern in leaves and tubers using different sets of transcriptome data. Moreover, we wanted to uncover transcription factors co-regulated with starch accumulation in tubers in order to get insight into the regulation of starch metabolism. We identified 77 genomic loci encoding enzymes involved in starch metabolism. Novel isoforms of many enzymes were found. Their analysis will help to elucidate mechanisms of starch biosynthesis and degradation. Expression analysis of starch genes led to the identification of tissue-specific isoenzymes suggesting differences in the transcriptional regulation of starch metabolism between potato leaf and tuber tissues. Selection of genes predominantly expressed in developing potato tubers and exhibiting an expression pattern indicative for a role in starch biosynthesis enabled the identification of possible transcriptional regulators of tuber starch biosynthesis by co-expression analysis. This study provides the annotation of the complete set of starch metabolic genes in potato plants and their genomic localizations. Novel, so far undescribed, enzyme isoforms were revealed. Comparative transcriptome analysis enabled the identification of tuber- and leaf-specific isoforms of starch genes. This finding suggests distinct regulatory mechanisms in transitory and storage starch metabolism. Putative regulatory proteins of starch biosynthesis in potato tubers have been identified by co-expression and their expression was verified by quantitative RT-PCR.

Changes of multi-scale structure during mimicked DSC heating reveal the nature of starch gelatinization

NASA Astrophysics Data System (ADS)

Wang, Shujun; Zhang, Xiu; Wang, Shuo; Copeland, Les

2016-06-01

A thorough understanding of starch gelatinization is extremely important for precise control of starch functional properties for food processing and human nutrition. Here we reveal the molecular mechanism of starch gelatinization by differential scanning calorimetry (DSC) in conjunction with a protocol using the rapid viscosity analyzer (RVA) to generate material for analysis under conditions that simulated the DSC heating profiles. The results from DSC, FTIR, Raman, X-ray diffraction and small angle X-ray scattering (SAXS) analyses all showed that residual structural order remained in starch that was heated to the DSC endotherm end temperature in starch:water mixtures of 0.5 to 4:1 (v/w). We conclude from this study that the DSC endotherm of starch at a water:starch ratio of 2 to 4 (v/w) does not represent complete starch gelatinization. The DSC endotherm of starch involves not only the water uptake and swelling of amorphous regions, but also the melting of starch crystallites.

Effects of grain development on formation of resistant starch in rice.

PubMed

Shu, Xiaoli; Sun, Jian; Wu, Dianxing

2014-12-01

Three rice mutants with different contents of resistant starch (RS) were selected to investigate the effects of grain filling process on the formation of resistant starch. During grain development, the content of RS was increased with grain maturation and showed negative correlations with the grain weight and the starch molecular weight (Mn, Mw) and a positive correlation with the distribution of molecular mass (polydispersity, Pd). The morphologies of starch granules in high-RS rice were almost uniform in single starch granules and exhibited different proliferation modes from common rice. The lower activities of ADP-glucose pyrophosphorylase and starch branching enzyme and the higher activity of starch synthase and starch de-branching enzyme observed in high-RS rice might be responsible for the formation of small irregular starch granules with large spaces between them. In addition, the lower molecular weight and the broad distribution of molecular weights lead to differences in the physiochemical properties of starch. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of waxy rice flour and cassava starch on freeze-thaw stability of rice starch gels.

PubMed

Charoenrein, Sanguansri; Preechathammawong, Nutsuda

2012-10-01

Repeatedly frozen and thawed rice starch gel affects quality. This study investigated how incorporating waxy rice flour (WF) and cassava starch (CS) in rice starch gel affects factors used to measure quality. When rice starch gels containing 0-2% WF and CS were subjected to 5 freeze-thaw cycles, both WF and CS reduced the syneresis in first few cycles. However CS was more effective in reducing syneresis than WF. The different composite arrangement of rice starch with WF or CS caused different mechanisms associated with the rice starch gel retardation of retrogradation, reduced the spongy structure and lowered syneresis. Both swollen granules of rice starch and CS caused an increase in the hardness of the unfrozen and freeze-thawed starch gel while highly swollen WF granules caused softer gels. These results suggested that WF and CS were effective in preserving quality in frozen rice starch based products. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of single and dual physical modifications on pinhão starch.

PubMed

Pinto, Vânia Zanella; Vanier, Nathan Levien; Deon, Vinicius Gonçalves; Moomand, Khalid; El Halal, Shanise Lisie Mello; Zavareze, Elessandra da Rosa; Lim, Loong-Tak; Dias, Alvaro Renato Guerra

2015-11-15

Pinhão starch was modified by annealing (ANN), heat-moisture (HMT) or sonication (SNT) treatments. The starch was also modified by a combination of these treatments (ANN-HMT, ANN-SNT, HMT-ANN, HMT-SNT, SNT-ANN, SNT-HMT). Whole starch and debranched starch fractions were analyzed by gel-permeation chromatography. Moreover, crystallinity, morphology, swelling power, solubility, pasting and gelatinization characteristics were evaluated. Native and single ANN and SNT-treated starches exhibited a CA-type crystalline structure while other modified starches showed an A-type structure. The relative crystallinity increased in ANN-treated starches and decreased in single HMT- and SNT-treated starches. The ANN, HMT and SNT did not provide visible cracks, notches or grooves to pinhão starch granule. SNT applied as second treatment was able to increase the peak viscosity of single ANN- and HMT-treated starches. HMT used alone or in dual modifications promoted the strongest effect on gelatinization temperatures and enthalpy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Changes of multi-scale structure during mimicked DSC heating reveal the nature of starch gelatinization

PubMed Central

Wang, Shujun; Zhang, Xiu; Wang, Shuo; Copeland, Les

2016-01-01

A thorough understanding of starch gelatinization is extremely important for precise control of starch functional properties for food processing and human nutrition. Here we reveal the molecular mechanism of starch gelatinization by differential scanning calorimetry (DSC) in conjunction with a protocol using the rapid viscosity analyzer (RVA) to generate material for analysis under conditions that simulated the DSC heating profiles. The results from DSC, FTIR, Raman, X-ray diffraction and small angle X-ray scattering (SAXS) analyses all showed that residual structural order remained in starch that was heated to the DSC endotherm end temperature in starch:water mixtures of 0.5 to 4:1 (v/w). We conclude from this study that the DSC endotherm of starch at a water:starch ratio of 2 to 4 (v/w) does not represent complete starch gelatinization. The DSC endotherm of starch involves not only the water uptake and swelling of amorphous regions, but also the melting of starch crystallites. PMID:27319782

Physicochemical properties and starch digestibility of whole grain sorghums, millet, quinoa and amaranth flours, as affected by starch and non-starch constituents.

PubMed

Srichuwong, Sathaporn; Curti, Delphine; Austin, Sean; King, Roberto; Lamothe, Lisa; Gloria-Hernandez, Hugo

2017-10-15

Minor grains such as sorghum, millet, quinoa and amaranth can be alternatives to wheat and corn as ingredients for whole grain and gluten-free products. In this study, influences of starch structures and other grain constituents on physicochemical properties and starch digestibility of whole flours made from these grains were investigated. Starches were classified into two groups according to their amylopectin branch chain-length: (i) quinoa, amaranth, wheat (shorter chains); and (ii) sorghum, millet, corn (longer chains). Such amylopectin features and amylose content contributed to the differences in thermal and pasting properties as well as starch digestibility of the flours. Non-starch constituents had additional impacts; proteins delayed starch gelatinization and pasting, especially in sorghum flours, and high levels of soluble fibre retarded starch retrogradation in wheat, quinoa and amaranth flours. Enzymatic hydrolysis of starch was restricted by the presence of associated protein matrix and enzyme inhibitors, but accelerated by endogenous amylolytic enzymes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Microstructure, thermal properties and crystallinity of amadumbe starch nanocrystals.

PubMed

Mukurumbira, Agnes; Mariano, Marcos; Dufresne, Alain; Mellem, John J; Amonsou, Eric O

2017-09-01

Amadumbe (Colocasia esculenta), commonly known as taro is a tropical tuber that produces starch-rich underground corms. In this study, the physicochemical properties of starch nanocrystals (SNC) prepared by acid hydrolysis of amadumbe starches were investigated. Two varieties of amadumbe corms were used for starch extraction. Amadumbe starches produced substantially high yield (25%) of SNC's. These nanocrystals appeared as aggregated and individual particles and possessed square-like platelet morphology with size: 50-100nm. FTIR revealed high peak intensities corresponding to OH stretch, CH stretch and H 2 O bending vibrations for SNCs compared to their native starch counterparts. Both the native starch and SNC exhibited the A-type crystalline pattern. However, amadumbe SNCs showed higher degree of crystallinity and slightly reduced melting temperatures than their native starches. Amadumbe SNCs presented similar thermal decomposition property as their native starches. Amadumbe starch nanocrystals may have potential application in biocomposite films due to their square-like platelet morphology. Copyright © 2017 Elsevier B.V. All rights reserved.

Morphology, structural and physicochemical properties of starch from the root of Cynanchum auriculatum Royle ex Wight.

PubMed

Liu, Jun; Wang, Xingchi; Wen, Fanting; Zhang, Shurong; Shen, Ruru; Jiang, Wei; Kan, Juan; Jin, Changhai

2016-12-01

The root of Cynanchum auriculatum Royle ex Wight is a traditional Chinese herbal medicine and healthy food. Although C. auriculatum has already been processed into starch for human consumption in China, the structural characterizations of C. auriculatum starch is still unknown. Therefore, the morphology, structural and physicochemical properties of C. auriculatum starch were investigated in this study. C. auriculatum starch exhibited both spherical and polygonal shapes with granule size ranging from 2 to 12μm. Some void cavities and serpentine channels were observed in the inner of starch granules. X-ray powder diffraction pattern revealed that C. auriculatum starch was a C B -type with relative crystallinity of 25.19%. Small-angle X-ray scattering spectrum indicated C. auriculatum starch had a lamellar repeat distance of 9.21nm. The proportions of single helix, double helix and amorphous components in C. auriculatum starch were 3.42%, 27.11% and 69.47%, respectively. The amylose content of C. auriculatum starch was 28.0% with the gelatinization temperature ranging from 59.3 to 70.1°C. The maximum weight loss rate of C. auriculatum starch appeared at 309°C. In addition, C. auriculatum starch showed higher swelling power than other starches tested. Our results suggest C. auriculatum starch will have wide applications in food industry. Copyright © 2016 Elsevier B.V. All rights reserved.

Quality evaluation of stiff porridges prepared from Irish potato (Solanum tuberosum) and pigeon pea (Cajanus cajan) starch blends.

PubMed

Abu, Joseph Oneh; Enyinnaya, Chinma Chiemela; James, Samaila; Okeleke, Ezinne

2012-06-01

Quality attributes of stiff porridges prepared from Irish potato and pigeon pea starch blends were studied. Starches were extracted from Irish potato and pigeon pea using a wet extraction method. Various ratios of the starches were mixed and analyzed for chemical, functional and pasting properties. The starch blends were then prepared into stiff porridges for sensory evaluation using a 20-man sensory panel. Substitution of Irish potato starch with pigeon pea starch led to increases in protein (0.15 to 1.2%), fat (0.26 to 0.56%) and ash (0.30 to 0.69%) while the amylose content of the starch blends decreased (from 23.8 to 18.4%) respectively. Functional properties such as bulk density (0.75 to 0.60 g/cm(3)), water absorption capacity (3.1 to 2.6 g water/ g sample) and dispersibility (58.6 to 42.7%) decreased significantly (P < 0.05) at the highest concentration (50%) of pigeon pea starch respectively. Pasting properties such as peak, breakdown, final and setback viscosities increased with increasing levels of pigeon pea starch while peak time and pasting temperature decreased. The sensory attributes of stiff porridges were not adversely affected by pigeon pea starch inclusion. Therefore it should be possible to incorporate up to 50% of low digestible pigeon pea starch into Irish potato starch from legumes such as pigeon pea as alternatives to cassava starch in the preparation of stiff porridges. Such porridges made from Irish potato and legume starches could provide additional incentive for individuals requiring decreased and or slow starch digestibility such as diabetics.

Mammalian mucosal α-glucosidases coordinate with α-amylase in the initial starch hydrolysis stage to have a role in starch digestion beyond glucogenesis.

PubMed

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R; Gidley, Michael J; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function.

Mammalian Mucosal α-Glucosidases Coordinate with α-Amylase in the Initial Starch Hydrolysis Stage to Have a Role in Starch Digestion beyond Glucogenesis

PubMed Central

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R.; Gidley, Michael J.; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function. PMID:23638112

Deficiency of Starch Synthase IIIa and IVb Alters Starch Granule Morphology from Polyhedral to Spherical in Rice Endosperm1

PubMed Central

Toyosawa, Yoshiko; Kawagoe, Yasushi; Matsushima, Ryo; Ogawa, Masahiro; Fukuda, Masako; Kumamaru, Toshihiro; Okazaki, Yozo; Kusano, Miyako; Saito, Kazuki; Toyooka, Kiminori; Sato, Mayuko; Ai, Yongfeng; Fujita, Naoko

2016-01-01

Starch granule morphology differs markedly among plant species. However, the mechanisms controlling starch granule morphology have not been elucidated. Rice (Oryza sativa) endosperm produces characteristic compound-type granules containing dozens of polyhedral starch granules within an amyloplast. Some other cereal species produce simple-type granules, in which only one starch granule is present per amyloplast. A double mutant rice deficient in the starch synthase (SS) genes SSIIIa and SSIVb (ss3a ss4b) produced spherical starch granules, whereas the parental single mutants produced polyhedral starch granules similar to the wild type. The ss3a ss4b amyloplasts contained compound-type starch granules during early developmental stages, and spherical granules were separated from each other during subsequent amyloplast development and seed dehydration. Analysis of glucan chain length distribution identified overlapping roles for SSIIIa and SSIVb in amylopectin chain synthesis, with a degree of polymerization of 42 or greater. Confocal fluorescence microscopy and immunoelectron microscopy of wild-type developing rice seeds revealed that the majority of SSIVb was localized between starch granules. Therefore, we propose that SSIIIa and SSIVb have crucial roles in determining starch granule morphology and in maintaining the amyloplast envelope structure. We present a model of spherical starch granule production. PMID:26747287

Enzymatically hydrolysed, acetylated and dually modified corn starch: physico-chemical, rheological and nutritional properties and effects on cake quality.

PubMed

Sahnoun, Mouna; Ismail, Nouha; Kammoun, Radhouane

2016-01-01

Corn starch was treated by enzymatic hydrolysis with Aspergillus oryzae S2 α-amylase, acetylation with vinyl acetate, and dual modification. The dual modified starch displayed a higher substitution degree than the acetylated starch and lower reducing sugar content than the hydrolysed starch. The results revealed that the cooling viscosity and amylose content of those products decrease (P < 0.05). An increase in moisture, water, and oil absorption capacity was observed for the acetylated starch and, which was less pronounced for the enzymatically hydrolysed starch but more pronounced for the enzymatically hydrolysed acetylated product. The latter product underwent an increase in resistant starch content, which is induced by a rise in hydrolysis time to attain about 67 % after 1 h of reaction. The modified starch samples were added to cake formulations at 5 and 10 % concentrations on a wheat flour basis and compared to native starch. The results revealed that when applied at 5 % concentrations, the modified starches reduced the hardness, cohesion, adhesion and chewiness of baked cakes and enhanced their elasticity, volume, height, crust color, and appearance as compared to native starch. These effects were more pronounced for the cake incorporating the dually modified starch.

Acetylated rice starches films with different levels of amylose: Mechanical, water vapor barrier, thermal, and biodegradability properties.

PubMed

Colussi, Rosana; Pinto, Vânia Zanella; El Halal, Shanise Lisie Mello; Biduski, Bárbara; Prietto, Luciana; Castilhos, Danilo Dufech; Zavareze, Elessandra da Rosa; Dias, Alvaro Renato Guerra

2017-04-15

Biodegradable films from native or acetylated starches with different amylose levels were prepared. The films were characterized according to the mechanical, water vapor barrier, thermal, and biodegradability properties. The films from acetylated high amylose starches had higher moisture content and water solubility than the native high amylose starch film. However, the acetylation did not affect acid solubility of the films, regardless of the amylose content. Films made from high and medium amylose rice starches were obtained; however low amylose rice starches, whether native or acetylated, did not form films with desirable characteristics. The acetylation decreased the tensile strength and increased the elongation of the films. The acetylated starch-based films had a lower decomposition temperature and higher thermal stability than native starch films. Acetylated starches films exhibited more rapid degradation as compared with the native starches films. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ionic liquids as novel solvents for biosynthesis of octenyl succinic anhydride-modified waxy maize starch.

PubMed

Li, Dandan; Zhang, Xiwen; Tian, Yaoqi

2016-05-01

Biosynthesis of octenyl succinic anhydride (OSA) starch was investigated using ionic liquids (ILs) as reaction media. Waxy maize starch was pretreated in 1-butyl-3-methylimidazolium chlorine and then esterified with OSA in 1-octyl-3-methylimidazolium nitrate by using Novozyme 435 as catalyst. The degree of substitution of OSA starch reached 0.0130 with 5 wt% starch concentration and 1 wt% lipase dosage based on ILs weight at 50 °C for 3h. The formation of OSA starch was confirmed by fourier transform infrared spectroscopy. Scanning electron microscopy and X-ray diffraction revealed that the morphology and crystal structure of starch were significantly destroyed. Thermogravimetric analysis showed that esterification decreased the thermal stability of starch. The successful lipase-catalyzed synthesis of OSA starch in ILs suggests that ILs are potential replacement of traditional organic solvents for starch ester biosynthesis. Copyright © 2016 Elsevier B.V. All rights reserved.

Preparation of low digestible and viscoelastic tigernut (Cyperus esculentus) starch by Bacillus acidopullulyticus pullulanase.

PubMed

Li, Xiaolei; Fu, Jingchao; Wang, Yujuan; Ma, Fumin; Li, Dan

2017-09-01

Tigernut starch is an underutilized food resource. In this study, pullulanase (PUL) hydrolysis was used to change its physiochemical properties for different food applications. The content of low digestible fractions, resistant starch and slow digestible starch, in PUL modified tigernut starch significantly increased from 2.03% to 25.08% (P<0.05) using 100U/g starch of PUL in the debranching reaction. The paste or dispersion of PUL modified tigernut starch had a significantly decreased viscoelasticity (P<0.05), but the paste still exhibited a typical property of pseudoplasticity. Molecular weight, amylopectin A B2 and B3 chain of PUL modified starch were lower, while amylose content, amylopectin B1 chain were higher than those of natural tigernut starch. The low digestible and viscous tigernut starch is highly valued as a component in some functional foods. Copyright © 2017 Elsevier B.V. All rights reserved.

Association mapping of starch chain length distribution and amylose content in pea (Pisum sativum L.) using carbohydrate metabolism candidate genes.

PubMed

Carpenter, Margaret A; Shaw, Martin; Cooper, Rebecca D; Frew, Tonya J; Butler, Ruth C; Murray, Sarah R; Moya, Leire; Coyne, Clarice J; Timmerman-Vaughan, Gail M

2017-08-01

Although starch consists of large macromolecules composed of glucose units linked by α-1,4-glycosidic linkages with α-1,6-glycosidic branchpoints, variation in starch structural and functional properties is found both within and between species. Interest in starch genetics is based on the importance of starch in food and industrial processes, with the potential of genetics to provide novel starches. The starch metabolic pathway is complex but has been characterized in diverse plant species, including pea. To understand how allelic variation in the pea starch metabolic pathway affects starch structure and percent amylose, partial sequences of 25 candidate genes were characterized for polymorphisms using a panel of 92 diverse pea lines. Variation in the percent amylose composition of extracted seed starch and (amylopectin) chain length distribution, one measure of starch structure, were characterized for these lines. Association mapping was undertaken to identify polymorphisms associated with the variation in starch chain length distribution and percent amylose, using a mixed linear model that incorporated population structure and kinship. Associations were found for polymorphisms in seven candidate genes plus Mendel's r locus (which conditions the round versus wrinkled seed phenotype). The genes with associated polymorphisms are involved in the substrate supply, chain elongation and branching stages of the pea carbohydrate and starch metabolic pathways. The association of polymorphisms in carbohydrate and starch metabolic genes with variation in amylopectin chain length distribution and percent amylose may help to guide manipulation of pea seed starch structural and functional properties through plant breeding.

Mechanical and barrier properties of maize starch-gelatin composite films: effects of amylose content.

PubMed

Wang, Kun; Wang, Wenhang; Ye, Ran; Xiao, Jingdong; Liu, Yaowei; Ding, Junsheng; Zhang, Shaojing; Liu, Anjun

2017-08-01

In order to obtain new reinforcing bio-fillers to improve the physicochemical properties of gelatin-based films, three types of maize starch, waxy maize starch (Ap), normal starch (Ns) and high-amylose starch (Al), were incorporated into gelatin film and the resulting film properties were investigated, focusing on the impact of amylose content. The thickness, opacity and roughness of gelatin film increased depending on the amylose content along with the starch concentration. The effects of the three starches on the mechanical properties of gelatin film were governed by amylose content, starch concentration as well as environmental relative humidity (RH). At 75% RH, the presence of Al and Ns in the gelatin matrix increased the film strength but decreased its elongation, while Ap exhibited an inverse effect. Starch addition decreased the oxygen permeability of the film, with the lowest value at 20% Al and Ns. All starches, notably at 30% content, led to a decrease in the water vapor permeability of the film at 90% RH, especially Ns starch. Furthermore, the starches improved the thermal stability of the film to some extent. Fourier transform infrared spectra indicated that some weak intermolecular interactions such as hydrogen bonding occurred between gelatin and starch. Moreover, a high degree of B-type crystallinity of starch was characterized in Gel-Al film by X-ray diffraction. Tailoring the properties of gelatin film by the incorporation of different types of maize starch provides the potential to extend its applications in edible food packaging. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Effects of sorghum (Sorghum bicolor (L.) Moench) tannins on alpha-amylase activity and in vitro digestibility of starch in raw and processed flours

USDA-ARS?s Scientific Manuscript database

The effect of condensed tannins (CT) on in vitro starch digestibility in cooked, wholegrain sorghum flours and on corn starch was investigated. CT extracts were also tested for their inhibitory effect on alpha-amylases. Rapidly digestible starch, slowly digestible starch, and resistant starch were n...

Characterisation of Physicochemical Properties of Propionylated Corn Starch and Its Application as Stabiliser

PubMed Central

Hong, Lee-Fen; Cheng, Lai-Hoong; Lee, Chong Yew

2015-01-01

Summary A series of propionylated starches with different degrees of substitution (DS) was synthesised and their physicochemical properties and application as a stabiliser were investigated. Starch propionates with moderate DS were prepared by esterification of native corn starch with propionic anhydride. By varying the reaction times of the esterification process, twelve starch propionates with DS of 0.47 to 0.94 were prepared. FTIR and NMR confirmed the introduction of propionyl groups to the starch. X-ray diffraction pattern showed reduced crystallinity in the starch propionates. The contact angle was found to increase proportionately with the increase in DS. Swelling power results showed that starch propionates were able to swell more than native corn starch at low temperature (40 °C). Oil-in- -water (O/W) emulsions prepared using starch propionates (DS of 0.64 to 0.86) showed exceptional stability when challenged by centrifugation stress test. These stable O/W emulsions had viscosities in the range of 1236.7–3330.0 mPa·s. In conclusion, moderately substituted short-chain (propionylated) starches could be a promising cold swelling starch, thickener and O/W emulsion stabiliser in food, pharmaceutical and cosmetic industries. PMID:27904359

Full-time response of starch subjected to microwave heating.

PubMed

Fan, Daming; Wang, Liyun; Zhang, Nana; Xiong, Lei; Huang, Luelue; Zhao, Jianxin; Wang, Mingfu; Zhang, Hao

2017-06-21

The effect of non-ionizing microwave radiation on starch is due to a gelatinization temperature range that changes starch structure and properties. However, the changes in starch upon microwave heating are observable throughout the heating process. We compared the effects on starch heating by microwaves to the effects by rapid and regular conventional heating. Our results show that microwave heating promotes the rapid rearrangement of starch molecules at low temperatures; starch showed a stable dielectric response and a high dielectric constant. Microwave heating changed the Cole-Cole curve and the polarization of starch suspension at low temperatures. A marked transition at 2.45 GHz resulted in a double-polarization phenomenon. At temperatures below gelatinization, microwave-induced dielectric rearrangement and changes in the polarization characteristics of starch suspensions reduced the absorption properties; at temperatures above gelatinization, these characteristics became consistent with conventional heating. Throughout the heating process, microwaves change the electrical response and polarization characteristics of the starch at low temperatures, but on the macro level, there is no enhancement of the material's microwave absorption properties. In contrast, with the warming process, the starch exhibited a "blocking effect", and the absorption properties of the starch quickly returned to the level observed in conductive heating after gelatinization.

Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative

PubMed Central

Sagnelli, Domenico; Kemmer, Gerdi Christine; Holse, Mette; Hebelstrup, Kim H.; Bao, Jinsong; Stelte, Wolfgang; Bjerre, Anne-Belinda; Blennow, Andreas

2017-01-01

Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO), an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi© plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material. PMID:28973963

Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative.

PubMed

Sagnelli, Domenico; Hooshmand, Kourosh; Kemmer, Gerdi Christine; Kirkensgaard, Jacob J K; Mortensen, Kell; Giosafatto, Concetta Valeria L; Holse, Mette; Hebelstrup, Kim H; Bao, Jinsong; Stelte, Wolfgang; Bjerre, Anne-Belinda; Blennow, Andreas

2017-09-30

Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO), an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi © plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material.

Comparison of gamma radiation effects on natural corn and potato starches and modified cassava starch

NASA Astrophysics Data System (ADS)

Teixeira, Bruna S.; Garcia, Rafael H. L.; Takinami, Patricia Y. I.; del Mastro, Nelida L.

2018-01-01

The objective of this work was to evaluate the effect of irradiation treatment on physicochemical properties of three natural polymers, i.e. native potato and corn starches and a typical Brazilian product, cassava starch modified through fermentation -sour cassava- and also to prepare composite hydrocolloid films based on them. Starches were irradiated in a 60Co irradiation chamber in doses up to 15 kGy, dose rate about 1 kGy/h. Differences were found in granule size distribution upon irradiation, mainly for corn and cassava starch but radiation did not cause significant changes in granule morphology. The viscosity of the potato, corn and cassava starches hydrogels decreased as a function of absorbed dose. Comparing non-irradiated and irradiated starches, changes in the Fourier transform infrared (FTIR) spectra in the 2000-1500 cm-1 region for potato and corn starches were observed but not for the cassava starch. Maximum rupture force of the starch-based films was affected differently for each starch type; color analysis showed that doses of 15 kGy promoted a slight rise in the parameter b* (yellow color) while the parameter L* (lightness) was not significantly affected; X-ray diffraction patterns remained almost unchanged by irradiation.

Molecular structure, functionality and applications of oxidized starches: A review.

PubMed

Vanier, Nathan Levien; El Halal, Shanise Lisie Mello; Dias, Alvaro Renato Guerra; da Rosa Zavareze, Elessandra

2017-04-15

During oxidation, the hydroxyl groups of starch molecules are first oxidized to carbonyl groups, then to carboxyl groups. The contents of the carbonyl and carboxyl groups in a starch molecule therefore indicate the extent of starch oxidation. The mechanisms of starch oxidation with different oxidizing agents, including sodium hypochlorite, hydrogen peroxide, ozone and sodium periodate, are described in this review. The effects of these oxidizing agents on the molecular, physicochemical, thermal, pasting and morphological properties of starch are described as well. In addition, the main industrial applications of oxidized starches are presented. The present review is important for understanding the effects of oxidation on starch properties, and this information may facilitate the development of novel oxidized starches for both food and non-food applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

High amylose starch consumption induces obesity in Drosophila melanogaster and metformin partially prevents accumulation of storage lipids and shortens lifespan of the insects.

PubMed

Abrat, Oleksandra B; Storey, Janet M; Storey, Kenneth B; Lushchak, Volodymyr I

2018-01-01

There are very few studies that have directly analyzed the effects of dietary intake of slowly digestible starches on metabolic parameters of animals. The present study examined the effects of slowly digestible starch with high amylose content (referred also as amylose starch) either alone, or in combination with metformin on the development, lifespan, and levels of glucose and storage lipids in the fruit fly Drosophila melanogaster. Consumption of amylose starch in concentrations 0.25-10% did not affect D. melanogaster development, whereas 20% starch delayed pupation and reduced the number of larvae that reached the pupal stage. Starch levels in larval food, but not in adult food, determined levels of triacylglycerides in eight-day-old adult flies. Rearing on diet with 20% starch led to shorter lifespan and a higher content of triacylglycerides in the bodies of adult flies as compared with the same parameters in flies fed on 4% starch diet. Food supplementation with 10mM metformin partly attenuated the negative effects of high starch concentrations on larval pupation and decreased triacylglyceride levels in adult flies fed on 20% starch. Long-term consumption of diets supplemented with metformin and starch decreased lifespan of the insects, compared with the diet supplemented with starch only. The data show that in Drosophila high starch consumption may induce a fat fly phenotype and metformin may partially prevent it. Copyright © 2017. Published by Elsevier Inc.

Gradually Decreasing Starch Branching Enzyme Expression Is Responsible for the Formation of Heterogeneous Starch Granules1[OPEN

PubMed Central

Hu, Pan; Chen, Zichun

2018-01-01

Rice (Oryza sativa) endosperm is mainly occupied by homogeneous polygonal starch from inside to outside. However, morphologically different (heterogeneous) starches have been identified in some rice mutants. How these heterogeneous starches form remains unknown. A high-amylose rice line (TRS) generated through the antisense inhibition of starch branching synthase I (SBEI) and SBEIIb contains four heterogeneous starches: polygonal, aggregate, elongated, and hollow starch; these starches are regionally distributed in the endosperm from inside to outside. Here, we investigated the relationship between SBE dosage and the morphological architecture of heterogeneous starches in TRS endosperm from the view of the molecular structure of starch. The results indicated that their molecular structures underwent regular changes, including gradually increasing true amylose content but decreasing amylopectin content and gradually increasing the ratio of amylopectin long chain but decreasing the ratio of amylopectin short chain. Granule-bound starch synthase I (GBSSI) amounts in the four heterogeneous starches were not significantly different from each other, but SBEI, SBEIIa, and SBEIIb showed a gradually decreasing trend. Further immunostaining analysis revealed that the gradually decreasing SBEs acting on the formation of the four heterogeneous granules were mainly due to the spatial distribution of the three SBEs in the endosperm. It was suggested that the decreased amylopectin in starch might remove steric hindrance and provide extra space for abundant amylose accumulation when the GBSSI amount was not elevated. Furthermore, extra amylose coupled with altered amylopectin structure possibly led to morphological changes in heterogeneous granules. PMID:29133372

Resistant starch improvement of rice starches under a combination of acid and heat-moisture treatments.

PubMed

Hung, Pham Van; Vien, Ngo Lam; Lan Phi, Nguyen Thi

2016-01-15

The effects of a combination of acid and heat-moisture treatment on formation of resistant starch (RS) and characteristics of high-amylose, normal and waxy rice starches were investigated in this study. The degrees of polymerization of the rice starches treated with citric acid, lactic acid or acetic acid were significantly reduced as compared to the native starches. The RS contents of acid and heat-moisture treated rice starches were in a range of 30.1-39.0%, significantly higher than those of native rice starches (6.3-10.2%) and those of heat-moisture treated rice starches (18.5-23.9%). The acid and heat-moisture treatments reduced swelling power and viscosity, but increased solubility of the starches, while the crystalline structure did not change. Among the organic acids used, citric acid had the most impact on starch characteristics and RS formation, followed by lactic acid and acetic acid. The results are useful in production of RS for functional food application. Copyright © 2015 Elsevier Ltd. All rights reserved.

Starch blockers--their effect on calorie absorption from a high-starch meal.

PubMed

Bo-Linn, G W; Santa Ana, C A; Morawski, S G; Fordtran, J S

1982-12-02

It has been known for more than 25 years that certain plant foods, such as kidney beans and wheat, contain a substance that inhibits the activity of salivary and pancreatic amylase. More recently, this antiamylase has been purified and marketed for use in weight control under the generic name "starch blockers." Although this approach to weight control is highly popular, it has never been shown whether starch-blocker tablets actually reduce the absorption of calories from starch. Using a one-day calorie-balance technique and a high-starch (100 g) meal (spaghetti, tomato sauce, and bread), we measured the excretion of fecal calories after normal subjects had taken either placebo or starch-blocker tablets. If the starch-blocker tablets had prevented the digestion of starch, fecal calorie excretion should have increased by 400 kcal. However, fecal calorie excretion was the same on the two test days (mean +/- S.E.M., 80 +/- 4 as compared with 78 +/- 2). We conclude that starch-blocker tablets do not inhibit the digestion and absorption of starch calories in human beings.

Tartary buckwheat (Fagopyrum tataricum Gaertn.) starch, a side product in functional food production, as a potential source of retrograded starch.

PubMed

Gao, Jinfeng; Kreft, Ivan; Chao, Guimei; Wang, Ying; Liu, Xiaojin; Wang, Li; Wang, Pengke; Gao, Xiaoli; Feng, Baili

2016-01-01

A starch rich fraction is a side product in Tartary buckwheat processing. This study investigated the fractions that are of technological and nutritional interest. Tartary buckwheat starch granules had a diameter of 3-14 μm, and presented a typical type "A" X-ray diffraction pattern. They contained nearly 39.0% amylose. The solubility of Tartary buckwheat starch was much lower at 70-90 °C (ranging within 9.9-10.4% at 90 °C) than that in maize (up to 49.3%) and potato (up to 85.0%) starch. The starch of one variety of Tartary buckwheat had significantly lower solubility at 70 °C and 80 °C than that of common buckwheat. The starch peak viscosity and breakdown were higher and pasting time was shorter in Tartary buckwheat than in that of the starch of common buckwheat. Tartary buckwheat starch had unique pasting and physicochemical properties, and is thereby capable of being exploited as a suitable raw material of retrograded starch in food processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Performance of Granular Starch with Controlled Pore Size during Hydrolysis with Digestive Enzymes.

PubMed

Benavent-Gil, Yaiza; Rosell, Cristina M

2017-12-01

Studies on porous starch have been directed to explore different industrial applications as bio-adsorbents of a variety of compounds. However, the analysis of starch digestibility is essential for food application. The objective of this study was to determine the impact of porous structure on in vitro starch digestibility. Porous starches were obtained using a range of concentrations of amyloglucosidase (AMG), α-amylase (AM), cyclodextrin-glycosyltransferase (CGTase) or branching enzyme (BE). Porous starches exhibited major content of digestible starch (DS) that increased with the intensity of the enzymatic treatment, and very low amount of resistant starch (RS). Porous starches behaved differently during in vitro hydrolysis depending on their enzymatic treatment. AMG was the unique treatment that increased the digestive amylolysis and estimated glycemic index, whereas AM, CGTase and BE reduced them. A significant relationship was found between the pore size and the severity of the amylolysis, suggesting that a specific pore size is required for the accessibility of the digestive amylase. Therefore, pore size in the starch surface was a limiting factor for digestion of starch granules.

The effect of amylose content and level of oxidation on the structural changes of acetylated corn starch and generation of free radicals.

PubMed

Pietrzyk, Sławomir; Fortuna, Teresa; Łabanowska, Maria; Juszczak, Lesław; Gałkowska, Dorota; Bączkowicz, Małgorzata; Kurdziel, Magdalena

2018-02-01

This study was aimed at determining the effect of starch oxidation on its acetylation, structure of starch granules, and generation of free radicals. Corn and waxy corn starches were oxidised by NaClO applied in doses of 10, 20, and 30g Cl/kg of starch, and then acetylated using acetic acid anhydride. The carboxyl, carbonyl, acetyl groups were determined in modified starches. Structural properties of starch granules were evaluated based on molecular weight distribution, gelatinisation, crystallinity, specific surface, intrinsic viscosity. EPR measurements were carried out to establish starch susceptibility to UV irradiation induced generation of free radicals. It was found that the number of carbon centered radicals was dependent on the kind of starch and its chemical modification. Study results allowed concluding that the applied modifications contributed to significant changes in starch granules that were determined not only by the amylose content of starch but also by the degree of its oxidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vivo quantification of plant starch reserves at micrometer resolution using X-ray microCT imaging and machine learning.

PubMed

Earles, J Mason; Knipfer, Thorsten; Tixier, Aude; Orozco, Jessica; Reyes, Clarissa; Zwieniecki, Maciej A; Brodersen, Craig R; McElrone, Andrew J

2018-03-08

Starch is the primary energy storage molecule used by most terrestrial plants to fuel respiration and growth during periods of limited to no photosynthesis, and its depletion can drive plant mortality. Destructive techniques at coarse spatial scales exist to quantify starch, but these techniques face methodological challenges that can lead to uncertainty about the lability of tissue-specific starch pools and their role in plant survival. Here, we demonstrate how X-ray microcomputed tomography (microCT) and a machine learning algorithm can be coupled to quantify plant starch content in vivo, repeatedly and nondestructively over time in grapevine stems (Vitis spp.). Starch content estimated for xylem axial and ray parenchyma cells from microCT images was correlated strongly with enzymatically measured bulk-tissue starch concentration on the same stems. After validating our machine learning algorithm, we then characterized the spatial distribution of starch concentration in living stems at micrometer resolution, and identified starch depletion in live plants under experimental conditions designed to halt photosynthesis and starch production, initiating the drawdown of stored starch pools. Using X-ray microCT technology for in vivo starch monitoring should enable novel research directed at resolving the spatial and temporal patterns of starch accumulation and depletion in woody plant species. No claim to original US Government works New Phytologist © 2018 New Phytologist Trust.

Extrusion and characterization of thermoplastic starch sheets from "macho" banana.

PubMed

Alanís-López, P; Pérez-González, J; Rendón-Villalobos, R; Jiménez-Pérez, A; Solorza-Feria, J

2011-08-01

Starch isolated from macho banana was oxidized by using 2.5% and 3.5% (w/w) of sodium hypochlorite. Native and oxidized starches with glycerol were processed using a conical twin screw extruder to obtain thermoplastic laminates or sheets, which were partially characterized. Oxidized banana starches presented higher moisture and total starch but lower ash, protein, lipids, and apparent amylose content than the native starch. Micrographs of sheets from oxidized starches showed wrinkles and cavities presumably caused by the plasticizer, but with less free glycerol and unplasticized starch granules than those from native starch. Sheets from oxidized starch showed a notorious increase in all thermal parameters (To, Tp, and ΔH), mechanical properties (tensile strength, elongation at break, and elasticity), and solubility. Banana starch X-ray diffraction patterns corresponded to a mixture of the A- and B-type polymorphs, with apparently slightly higher crystallinity in oxidized specimens than in native starch. A similar trend was observed in the corresponding sheets. Due to the pollution problem caused by the conventional plastics, there has been a renewed interest in biodegradable sheets, because they may have the potential to replace conventional packaging materials. Banana starch might be an interesting raw material to be used as edible sheet, coating or in food packaging, and preservation, because it is biodegradable, cheap, innocuous, and abundant. © 2011 Institute of Food Technologists®

Arabidopsis thaliana FAR-RED ELONGATED HYPOCOTYLS3 (FHY3) and FAR-RED-IMPAIRED RESPONSE1 (FAR1) modulate starch synthesis in response to light and sugar.

PubMed

Ma, Lin; Xue, Na; Fu, Xiaoyu; Zhang, Haisen; Li, Gang

2017-03-01

In living organisms, daily light/dark cycles profoundly affect cellular processes. In plants, optimal growth and development, and adaptation to daily light-dark cycles, require starch synthesis and turnover. However, the underlying molecular mechanisms coordinating daily starch metabolism remain poorly understood. To explore the roles of Arabidopsis thaliana light signal transduction proteins FAR-RED ELONGATED HYPOCOTYLS3 (FHY3) and FAR-RED-IMPAIRED RESPONSE1 (FAR1) in starch metabolism, the contents of starch and water-soluble polysaccharides, and the structure of starch granules were investigated in fhy3, far1 and fhy3 far1 mutant plants. Disruption of FHY3 or FAR1 reduced starch accumulation and altered starch granule structure in the fhy3-4, far1-2, and fhy3-4 far1-2 mutant plants. Furthermore, molecular and genetic evidence revealed that the gene encoding the starch-debranching enzyme ISOAMYLASE2 (ISA2) is a direct target of FHY3 and FAR1, and functions in light-induced starch synthesis. Our data establish the first molecular link between light signal transduction and starch synthesis, suggesting that the light-signaling proteins FHY3 and FAR1 influence starch synthesis and starch granule formation through transcriptional activation of ISA2. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Paraformaldehyde-Resistant Starch-Fermenting Bacteria in “Starch-Base” Drilling Mud

PubMed Central

Myers, G. E.

1962-01-01

Starch-fermenting bacteria were found in each of 12 samples of nonfermenting starch-base drilling mud examined. Of the 12 samples, 3 contained very active starch-fermenting gram-positive spore-bearing bacilli closely resembling Bacillus subtilis. Similar active starch-fermenting bacteria were found in fermenting starch-base drilling mud and in corn starch and slough water used to prepare such mud. The active starch-fermenting microorganisms completely hydrolyzed 1% (w/v) corn starch within 24 hr at 37.5 C. The active starch-fermenting bacteria isolated from fermenting drilling mud were capable of surviving 12 hr of continuous exposure to 0.1% (w/w) paraformaldehyde or 1 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, with no diminution in starch-fermenting ability. The same organisms fermented starch after 3 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, but not after 4 hr of exposure. The phenomenon of rapid disappearance of paraformaldehyde from fermenting drilling mud was observed in the laboratory using a modified sodium sulfite test. Paraformaldehyde, initially present in a concentration of 0.192 lb per barrel of mud, completely disappeared in 9 hr at 22 to 23 C. A significant decrease in paraformaldehyde concentration was detected 0.5 hr after preparation of the mud. It is suggested that the presence of relatively high concentrations of ammonia and chloride in the mud may facilitate the disappearance of paraformaldehyde. The failure of 0.1% (w/w) paraformaldehyde to inhibit the strong starch-fermenting microorganisms isolated from fermenting drilling mud, and the rapid disappearance of paraformaldehyde from the mud, explains the fermentation of starch which occurred in this mud, despite the addition of paraformaldehyde. PMID:13936949

Gelatinized to non-gelatinized starch ratio in the diet of Labeo rohita: effect on digestive and metabolic response and on growth.

PubMed

Kumar, V; Sahu, N P; Pal, A K; Kumar, S; Gupta, S K

2008-08-01

A 60-days experiment was conducted to study the optimum gelatinized (G) to non-gelatinized (NG) starch ratio in the diet of Labeo rohita juveniles with respect to digestive and metabolic response and on growth. Two-hundred and thirty-four juveniles (avg. wt 2.53 +/- 0.04 g) were randomly distributed in six treatment groups with each of three replicates. Six semipurified diets either containing NG and/or G corn starch viz., T(1) (100% NG, 0% G starch), T(2) (80% NG, 20% G starch), T(3) (60% NG, 40% G starch), T(4) (40% NG, 60% G starch), T(5) (20% NG, 80% G starch) and T(6) (0% NG, 100% G starch) were prepared. The dry matter digestibility and carbohydrate digestibility were highest (p < 0.05) in T(6) group and lowest in T(3) and T(4) groups. The amylase activity in intestine increased as G:NG level increased in the diet. Protease activity in intestine was highest in T(6) group and lowest in T(1) group. Similar trend was recorded for specific growth rate, protein efficiency ratio and apparent net protein utilization. Liver glycogen, hepatosomatic index and blood glucose level increased linearly with the increasing level of G starch in the experimental diet. The results indicate that higher nutrient digestibility and growth was recorded either at low (20% G starch, T(2)) or high (100% G starch, T(6)) G starch fed group. But high G starch fed group (T(6)) exhibits higher liver glycogen and blood glucose level, which may lead to stress due to long-term feeding. Hence, it is suggested that 20% G and 80% NG starch is optimum for better nutrient digestibility and growth in L. rohita juveniles.

Dynamic high-pressure microfluidization assisting octenyl succinic anhydride modification of rice starch.

PubMed

Li, Yu-Ting; Wang, Ri-Si; Liang, Rui-Hong; Chen, Jun; He, Xiao-Hong; Chen, Rui-Yun; Liu, Wei; Liu, Cheng-Mei

2018-08-01

Octenyl succinic anhydride (OSA) modified starch is widely used in food industries. In this study, rice starch (RS) was pretreated by dynamic high-pressure microfluidization (DHPM) and subsequently modified by OSA. The influence of DHPM on OSA modification of rice starch was investigated. Results showed that DHPM pretreatment enhanced the degree of substitution by changing the morphology and crystallinity of rice starch. Compared with the rice starch modified by OSA without DHPM pretreatment (OSA-RS), the DHPM-pretreated OSA starch (DHPM-OSA-RS) presented higher peak viscosity and lower pasting temperature. DHPM-OSA-RS also exhibited better emulsifying activity and emulsion stability. This study suggested that DHPM will provide an opportunity to change the physicochemical properties of starch, with the resulting starch being more suitable for chemical modification. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterisation of corn starch-based films reinforced with taro starch nanoparticles.

PubMed

Dai, Lei; Qiu, Chao; Xiong, Liu; Sun, Qingjie

2015-05-01

Taro starch nanoparticles (TSNPs) obtained by hydrolysis with pullulanase and the recrystallisation of gelatinised starch were used as reinforcing agents in corn starch films. The influence of TSNPs contents (0.5-15%) on the physical, mechanical, thermal, and structural properties of starch films was investigated. An increase in the concentration of TSNPs led to a significant decrease in the water vapour permeability (WVP) of films. The addition of TSNPs increased the tensile strength (TS) of films from 1.11 MPa to 2.87 MPa. Compared with pure starch films, the surfaces of nanocomposite films became uneven. The onset temperature (To) and melting temperature (Tm) of films containing TSNPs were higher than those of pure starch films. The addition of TSNPs improved the thermal stability of starch films. Copyright © 2014 Elsevier Ltd. All rights reserved.

Slowly digestible starch diets alter proximal glucosidase activity and glucose absorption

USDA-ARS?s Scientific Manuscript database

Sucrase-isomaltase (Si) and maltase-glucoamylase (Mgam) are mucosal glucosidases required for digestion of starch to glucose. Ablation of maltase-Mgam reduces in vivo starch digestion. We tested whether slowly digestible starch diets induce changes in glucosidase activities. Rice starch was encaps...

Phosphate fertilization changes the characteristics of 'Maçã' banana starch.

PubMed

Mesquita, Camila de Barros; Garcia, Émerson Loli; Bolfarini, Ana Carolina Batista; Leonel, Sarita; Franco, Célia Maria L; Leonel, Magali

2018-06-01

The unripe banana has been studied as a potential source of starch for use in various applications. Considering the importance of phosphorus in the biosynthesis of the starch and also the interference of this mineral in starch properties, in this study it was evaluated the effect of rates of phosphate fertilizer applied in the cultivation of 'Maçã' banana on the characteristics of the starch. Starches extracted from fruits from different treatments were analyzed for morphological characteristics, X-ray diffraction pattern, relative crystallinity, granule size, amylose, resistant starch and phosphorus levels, as well as, for pasting and thermal properties. Results showed that the phosphate fertilization has interference on the characteristics of the banana starch led to increase of phosphorus content and size of the granules, reduction of crystallinity and resistant starch content, decrease of viscosity peak, breakdown, final viscosity, setback, transitions temperatures and enthalpy. These changes caused by phosphate fertilizer conditions can be increase the applications of the 'Maçã' banana starch. Copyright © 2018. Published by Elsevier B.V.

A comparative study of annealing of waxy, normal and high-amylose maize starches: the role of amylose molecules.

PubMed

Wang, Shujun; Wang, Jinrong; Yu, Jinglin; Wang, Shuo

2014-12-01

The effect of annealing on starch structure and functionality of three maize starches (waxy, normal and high-amylose) was investigated, with the aim of understanding the role of amylose molecules during starch annealing. Amylose content, granular morphology and crystallinity of maize starches were little affected by annealing treatment. Annealing treatment did not alter the swelling power of waxy maize starch, but reduced the swelling power of normal and high-amylose maize starches. The thermal transition temperatures were increased, and the temperature range was decreased, but the enthalpy change was not affected greatly. The pasting viscosities of normal and waxy maize starches were decreased significantly, with the pasting temperature being little affected. The in vitro digestibility of three maize starches was not affected significantly by annealing treatment. Our results demonstrated that amylose molecules play an important role in the structural reorganization of starch granules during annealing treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gel characteristics and microstructure of fish myofibrillar protein/cassava starch composites.

PubMed

Fan, Mingcong; Hu, Ting; Zhao, Siming; Xiong, Shanbai; Xie, Jing; Huang, Qilin

2017-03-01

The changes in fish myofibrillar protein/cassava starch composites in the starch fraction range from 0 to 1, with their total content maintained at 60mg/mL, were investigated in terms of textural properties, rheological behaviours, morphology, spatial distribution and protein molecular structure. The results revealed that the starch fraction of 0.5 was a critical point for the conversion of the protein matrix to starch matrix and conversion of the gel from elastic to weak. Moreover, the protein-starch synergistic effect on the storage modulus was strongest at fractions of 0.5 and 0.6, due to the formation of a semi-interpenetrating network, with more amylose from the melted starch granules interpenetrated with the protein molecules, and the absorption of water by the starch granules to concentrate the protein matrix. Additionally, no covalent interaction between the protein and starch occurred with increasing starch fraction, thus having no significant influence on the protein secondary structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Starch Spherulites Prepared by a Combination of Enzymatic and Acid Hydrolysis of Normal Corn Starch.

PubMed

Shang, Yaqian; Chao, Chen; Yu, Jinglin; Copeland, Les; Wang, Shuo; Wang, Shujun

2018-06-13

This paper describes a new method to prepare spherulites from normal corn starch by a combination of enzymatic (mixtures of α-amylase and amyloglucosidase) and acid hydrolysis followed by recrystallization of the hydrolyzed products. The resulting spherulites contained a higher proportion of chains with a degree of polymerization (DP) of 6-12 and a lower proportion of chains with DP of 25-36, compared to those of native starch. The spherulites had an even particle size of about 2 μm and a typical B-type crystallinity. The amounts of long- and short-range molecular order of double helices in starch spherulites were larger, but the quality of starch crystallites was poorer, compared to that of native starch. This study showed an efficient method for preparing starch spherulites with uniform granule morphology and small particle size from normal corn starch. The ratios of α-amylase and amyloglucosidase in enzymatic hydrolysis had little effect on the structure of the starch spherulites.

[Effect of acetylation and oxidation on some properties of breadfruit (Artocarpus altilis) seed starch].

PubMed

Rincón, Alicia Mariela; Bou Rached, Lizet; Aragoza, Luis E; Padilla, Fanny

2007-09-01

Starch extracted from seeds of Artocarpus altilis (Breadfruit) was chemically modified by acetylation and oxidation, and its functional properties were evaluated and compared with these of native starch. Analysis of the chemical composition showed that moisture content was higher for modified starches. Ash, protein, crude fiber and amylose contents were reduced by the modifications, but did not alter the native starch granules' irregularity, oval shape and smooth surface. Acetylation produced changes in water absorption, swelling power and soluble solids, these values were higher for acetylated starch, while values for native and oxidized starches were similar. Both modifications reduced pasting temperature; oxidation reduced maximum peak viscosity but it was increased by acetylation. Hot paste viscosity was reduced by both modifications, whereas cold paste viscosity was lower in the oxidized starch and higher in the acetylated starch. Breakdown was increased by acetylation and reduced with oxidation. Setback value was reduced after acetylation, indicating it could minimize retrogradation of the starch.

Altering the rate of glucose release from starch-based foods by spray-drying with an extract from barley.

PubMed

Razzaq, Hussam A A; Sutton, Kevin H; Motoi, Lidia

2013-08-30

Health outcomes associated with sustained elevated blood glucose may be better managed by limiting glucose availability for uptake. Glucose release from consumed starch may be altered using various methods, but many are not suitable for high-carbohydrate foods. This study describes an approach to protect starch granules, while generally maintaining their physical characteristics, with an extract from barley using spray-drying. The use of the extract resulted in the coating of the starch granules with a film-like material composed of β-glucans and proteins. This coincided with a reduction in starch digestion and a significant increase in the indigestible (resistant) starch component. Substitution of the starch component in a model snack bar by the coated starch was also associated with lowering starch digestion in the bar. The barley extract provides a physical barrier that may limit the exposure of starch to the digestive enzymes and water, with a consequent reduction in starch digestion and the rate of glucose release. It is possible, therefore, to produce wheat starch with lower digestibility and glucose release rate that may be used as a healthier substitute in high-carbohydrate foods by coating the granules with polymers extracted from barley cereals through spray-drying. © 2013 Society of Chemical Industry.

Resistant starch: a promising dietary agent for the prevention/treatment of inflammatory bowel disease and bowel cancer.

PubMed

Higgins, Janine A; Brown, Ian L

2013-03-01

Resistant starch represents a diverse range of indigestible starch-based dietary carbohydrates. Resistant starch has been investigated in the past for its effects on bowel health (pH, epithelial thickness, and apoptosis of colorectal cancer cells); reduction in postprandial glycemia; increased insulin sensitivity; and effects on the gut microbiome. This review highlights advances as resistant starch gains clinical relevance as a potential treatment/preventive tool for diseases such as colorectal cancer (CRC) and diabetes. Recent articles have evaluated the comparative physiological effects of different types of resistant starch and investigated the effects of resistant starch on blood lipids, body weight, and defining resistant starch-induced changes to the micriobiome that may be important in health and disease. The most novel and relevant recent data describe a role for resistant starch in ameliorating inflammation; the use of resistant starch for optimal bowel health and prevention of CRC; and, further, that the systemic effects of resistant starch may be important for the treatment of other forms of cancer, such as breast cancer. This review describes advances in resistant starch research highlighting the gastrointestinal effects that are now being linked to systemic, whole body effects with clinical relevance. These effects have important implications for overall health and the prevention or amelioration of various chronic diseases.

Effect of amylose, particle size & morphology on the functionality of starches of traditional rice cultivars.

PubMed

Bhat, Farhan Mohiuddin; Riar, Charanjit Singh

2016-11-01

The research was carried out to investigate the effect of starch powder particle size, morphology, amylose content and varietal effect on physicochemical, X-ray diffraction pattern, thermal and pasting characteristics. The results indicated that starches isolated from seven traditional rice cultivars of temperate region of India have possessed higher yield (82.47-86.83%) with lower degree of granule damage and higher level of starch crystallinity (36.55-39.15%). The water and oil binding capacities were observed to correlate positively with amylose content. The bulk density and color parameters of starches were found to have linked with starch powder particle size coupled with arrangement and morphology of the starch granules. The rice cultivars having smaller starch powder particle size indicated lowest degree of crystallinity. Morphological studies revealed that the starches with tightly packed granules had greater mean granular width, while granules with openly spaced granular morphology depicted the higher values for mean granular length. The peak height index (PHI) among different starches ranged from 1.01 to 2.57 whereas the gelatinization range varied from 10.66 to 10.88. Concluding, the differences in distributional pattern of starch granule size and shape and powder particle size indicated a significant effect on the functional properties of starch. Copyright © 2016 Elsevier B.V. All rights reserved.

Starch Origin and Thermal Processing Affect Starch Digestion in a Minipig Model of Pancreatic Exocrine Insufficiency.

PubMed

Mößeler, Anne; Vagt, Sandra; Beyerbach, Martin; Kamphues, Josef

2015-01-01

Although steatorrhea is the most obvious symptom of pancreatic exocrine insufficiency (PEI), enzymatic digestion of protein and starch is also impaired. Low praecaecal digestibility of starch causes a forced microbial fermentation accounting for energy losses and meteorism. To optimise dietetic measures, knowledge of praecaecal digestibility of starch is needed but such information from PEI patients is rare. Minipigs fitted with an ileocaecal fistula with (n = 3) or without (n = 3) pancreatic duct ligation (PL) were used to estimate the rate of praecaecal disappearance (pcD) of starch. Different botanical sources of starch (rice, amaranth, potato, and pea) were fed either raw or cooked. In the controls (C), there was an almost complete pcD (>92%) except for potato starch (61.5%) which was significantly lower. In PL pcD of raw starch was significantly lower for all sources of starch except for amaranth (87.9%). Thermal processing increased pcD in PL, reaching values of C for starch from rice, potato, and pea. This study clearly underlines the need for precise specification of starch used for patients with specific dietetic needs like PEI. Data should be generated in suitable animal models or patients as tests in healthy individuals would not have given similar conclusions.

Water dynamics and retrogradation of ultrahigh pressurized wheat starch.

PubMed

Doona, Christopher J; Feeherry, Florence E; Baik, Moo-Yeol

2006-09-06

The water dynamics and retrogradation kinetics behavior of gelatinized wheat starch by either ultrahigh pressure (UHP) processing or heat are investigated. Wheat starch completely gelatinized in the condition of 90, 000 psi at 25 degrees C for 30 min (pressurized gel) or 100 degrees C for 30 min (heated gel). The physical properties of the wheat starches were characterized in terms of proton relaxation times (T2 times) measured using time-domain nuclear magnetic resonance spectroscopy and evaluated using commercially available continuous distribution modeling software. Different T2 distributions in both micro- and millisecond ranges between pressurized and heated wheat starch gels suggest distinctively different water dynamics between pressurized and heated wheat starch gels. Smaller water self-diffusion coefficients were observed for pressurized wheat starch gels and are indicative of more restricted translational proton mobility than is observed with heated wheat starch gels. The physical characteristics associated with changes taking place during retrogradation were evaluated using melting curves obtained with differential scanning calorimetry. Less retrogradation was observed in pressurized wheat starch, and it may be related to a smaller quantity of freezable water in pressurized wheat starch. Starches comprise a major constituent of many foods proposed for commercial potential using UHP, and the present results furnish insight into the effect of UHP on starch gelatinization and the mechanism of retrogradation during storage.

Effect of acid hydrolysis on morphology, structure and digestion property of starch from Cynanchum auriculatum Royle ex Wight.

PubMed

Wang, Xingchi; Wen, Fanting; Zhang, Shurong; Shen, Ruru; Jiang, Wei; Liu, Jun

2017-03-01

Effect of acid hydrolysis on the morphology, structure and digestion property of starch from Cynanchum auriculatum Royle ex Wight was investigated in this study. The hydrolysis degree of C. auriculatum starch rapidly increased to 63.69% after 4days and reached 78.67% at the end of 9days. Morphology observation showed that the starch granules remained intact during the first 4days of hydrolysis. However, serious erosion phenomenon was observed after 5days and starch granules completely fell into pieces after 7days. During acid hydrolysis process, the crystal type of hydrolyzed starch changed from original C B -type to final A-type. Small-angle X-ray scattering patterns showed the semi-crystalline growth rings started to be hydrolyzed after 4days. The proportions of single helix and amorphous components as well as amylose content in starch gradually decreased, whereas the proportion of double helix components continuously increased during acid hydrolysis. However, the contents of rapidly digestible starch, slowly digestible starch and resistant starch were almost constant during acid hydrolysis process, indicating the in vitro digestion property of C. auriculatum starch was not affected by acid hydrolysis. Our results provided novel information on the inner structure of C. auriculatum starch granules. Copyright © 2017 Elsevier B.V. All rights reserved.

The Starch Granule-Associated Protein EARLY STARVATION1 Is Required for the Control of Starch Degradation in Arabidopsis thaliana Leaves[OPEN

PubMed Central

Feike, Doreen; Seung, David; Graf, Alexander; Bischof, Sylvain; Ellick, Tamaryn; Coiro, Mario; Soyk, Sebastian; Eicke, Simona; Mettler-Altmann, Tabea; Lu, Kuan Jen; Trick, Martin; Zeeman, Samuel C.

2016-01-01

To uncover components of the mechanism that adjusts the rate of leaf starch degradation to the length of the night, we devised a screen for mutant Arabidopsis thaliana plants in which starch reserves are prematurely exhausted. The mutation in one such mutant, named early starvation1 (esv1), eliminates a previously uncharacterized protein. Starch in mutant leaves is degraded rapidly and in a nonlinear fashion, so that reserves are exhausted 2 h prior to dawn. The ESV1 protein and a similar uncharacterized Arabidopsis protein (named Like ESV1 [LESV]) are located in the chloroplast stroma and are also bound into starch granules. The region of highest similarity between the two proteins contains a series of near-repeated motifs rich in tryptophan. Both proteins are conserved throughout starch-synthesizing organisms, from angiosperms and monocots to green algae. Analysis of transgenic plants lacking or overexpressing ESV1 or LESV, and of double mutants lacking ESV1 and another protein necessary for starch degradation, leads us to propose that these proteins function in the organization of the starch granule matrix. We argue that their misexpression affects starch degradation indirectly, by altering matrix organization and, thus, accessibility of starch polymers to starch-degrading enzymes. PMID:27207856

Starch--value addition by modification.

PubMed

Tharanathan, Rudrapatnam N

2005-01-01

Starch is one of the most important but flexible food ingredients possessing value added attributes for innumerable industrial applications. Its various chemically modified derivatives offer a great scope of high technological value in both food and non-food industries. Modified starches are designed to overcome one or more of the shortcomings, such as loss of viscosity and thickening power upon cooking and storage, particularly at low pH, retrogradation characteristics, syneresis, etc., of native starches. Oxidation, esterification, hydroxyalkylation, dextrinization, and cross-linking are some of the modifications commonly employed to prepare starch derivatives. In a way, starch modification provides desirable functional attributes as well as offering economic alternative to other hydrocolloid ingredients, such as gums and mucilages, which are unreliable in quality and availability. Resistant starch, a highly retrograded starch fractionformed upon food processing, is another useful starch derivative. It exhibits the beneficial physiological effects of therapeutic and nutritional values akin to dietary fiber. There awaits considerable opportunity for future developments, especially for tailor-made starch derivatives with multiple modifications and with the desired functional and nutritional properties, although the problem of obtaining legislative approval for the use of novel starch derivatives in processed food formulations is still under debate. Nevertheless, it can be predicted that new ventures in starch modifications and their diverse applications will continue to be of great interest in applied research.

Acetylation of banana (Musa paradisiaca L.) and corn (Zea mays L.) starches using a microwave heating procedure and iodine as catalyst: II. Rheological and structural studies.

PubMed

Sánchez-Rivera, Mirna M; Almanza-Benitez, Sirlen; Bello-Perez, Luis A; Mendez-Montealvo, Guadalupe; Núñez-Santiago, María C; Rodriguez-Ambriz, Sandra L; Gutierrez-Meráz, Felipe

2013-02-15

The effect of iodine concentration on the acetylation of starches with low and moderate degree of substitution (DS<0.5) and its impact on the physicochemical feature and structural features was evaluated. The acetylated starches were prepared with 0.03 mol anhydroglucose unit, 0.12 mol of anhydride acetic, and 0.6, 0.9 or 1.4 mM of molecular iodine as catalyst in a sealed Teflon vessel using microwave heating (600 W/2 min). Pasting profile and rheological properties were obtained under steady flow; dynamic oscillatory test was used. Structural features were obtained by HPSEC-RI. In acetylated starches, DS and acetyl groups increased when the iodine concentration increased, corn starch showed higher values than banana starch. The viscosity of acetylated starches decreased relative to unmodified starches while, acetylated corn starch had lower value than acetylated banana starch. In the flow curves, a non-Newtonian pattern (shear-thinning) was shown in the pastes of native and modified starches. Storage modulus (G') and loss modulus (G") showed low dependence on frequency (G'αω(0.1); G"αω(0.2)) on frequency sweep test, which is characteristic of a viscoelastic gel. Debranched native banana and corn starches presented trimodal chain-length distribution. The pattern was maintained in the acetylated starches, but with different level of short and long chains. The structural differences in native and acetylated samples explain the rheological characteristics in both starches. Copyright © 2012 Elsevier Ltd. All rights reserved.

Leaf Starch Turnover Occurs in Long Days and in Falling Light at the End of the Day.

PubMed

Fernandez, Olivier; Ishihara, Hirofumi; George, Gavin M; Mengin, Virginie; Flis, Anna; Sumner, Dean; Arrivault, Stéphanie; Feil, Regina; Lunn, John E; Zeeman, Samuel C; Smith, Alison M; Stitt, Mark

2017-08-01

We investigated whether starch degradation occurs at the same time as starch synthesis in Arabidopsis ( Arabidopsis thaliana ) leaves in the light. Starch accumulated in a linear fashion for about 12 h after dawn, then accumulation slowed and content plateaued. Following decreases in light intensity, the rate of accumulation of starch declined in proportion to the decline in photosynthesis if the decrease occurred <10 h after dawn, but accumulation ceased or loss of starch occurred if the same decrease in light intensity was imposed more than 10 h after dawn. These changes in starch accumulation patterns after prolonged periods in the light occurred at both high and low starch contents and were not related to time-dependent changes in either the rate of photosynthesis or the partitioning of assimilate between starch and Suc, as assessed from metabolite measurements and 14 CO 2 pulse experiments. Instead, measurements of incorporation of 13 C from 13 CO 2 into starch and of levels of the starch degradation product maltose showed that substantial starch degradation occurred simultaneously with synthesis at time points >14 h after dawn and in response to decreases in light intensity that occurred >10 h after dawn. Starch measurements in circadian clock mutants suggested that the clock influences the timing of onset of degradation. We conclude that the propensity for leaf starch to be degraded increases with time after dawn. The importance of this phenomenon for efficient use of carbon for growth in long days and for prevention of starvation during twilight is discussed. © 2017 American Society of Plant Biologists. All Rights Reserved.

Effect of dry heating and ionic gum on the physicochemical and release properties of starch from Dioscorea.

PubMed

Vashisht, Deepika; Pandey, Anima; Hermenean, Anca; Yáñez-Gascón, Maria Josefa; Pérez-Sánchez, Horacio; Kumar, K Jayaram

2017-02-01

To meet the ever increasing industrial demand for excipients with desirable properties, modified starch is regarded as an alternative to it. With this in mind, the present study focuses on the modification of starches of Dioscorea from Jharkhand (India) using dry heat treatment with and without ionic gum. Modified starches were prepared using sodium alginate (1% w/w). Native and modified starches were subjected to heat treatment at 130°C for 2h and 4h. The effect of heating and ionic gum on the properties of Dioscorea starch was investigated. The amylose content, water holding capacity, micromeritic properties, swelling power, solubility and morphology of starches were evaluated. Dry heat treatment of starches without gum showed an increment in water-holding capacity after two-hours heating, but no such increment was found after four-hours heating. Oil binding capacity of starches modified with gum varied from 62% to 78%. Strongest effect of heat treatment occurred on the morphology of starches and thereby modified starches showed distorted surface morphology. Amylose content (21.09-21.89%) found to be decreased with the addition of gum which lead to decrease in paste clarity. Starches heated with gum at high-temperature resulted in restrict swelling and slight increase in solubility. Micromeritic properties of the modified starches showed the good flow properties. Further, the modified starches were investigated for in-vitro release studies and that the thermally modified derivatives can be a good prospect in slow release formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of Modified Tapioca Starch in Atmospheric Argon Plasma under Diverse Humidity by FTIR Spectroscopy

NASA Astrophysics Data System (ADS)

Deeyai, P.; Suphantharika, M.; Wongsagonsup, R.; Dangtip, S.

2013-01-01

Tapioca is economical crop grown in Thailand and continues to be one of the major sources of starch. Nowadays, tapioca starch has been widely used in industrial applications, however the native form of starch has limited the applications. Thus scientists try to modify the properties of starch for increasing the stability of the granules, pastes to low pH, heat, and shear during the food process. We modify the tapioca starch by plasma treatment under an argon atmosphere. The degree of modification is determined by following water content in the starch granules. The tablet samples of native starch are also prepared and compared with the plasma treated starch. Before plasma treatment, the starch tablets are stored under three different relative humilities (RH) including 11%, 68%, and 78%RH, respectively. The samples are characterized using FTIR spectroscopy associated with the degree of cross-linking. The results show that the water molecules are engulfed into the starch structure in two ways, a tight bond and a weak absorption of water molecules which is represented at two wave number of 1630 cm-1 and 3272 cm-1, respectively. The degree of cross-linking can be identified from the relative intensity of these two peaks with the C—O—H peak at 993 cm-1. The results show that the degree of cross-linking increase in the plasma treated starch. The degree of cross-linking of the treated starch with high relative humidity is less than that of the treated starch with low relative humidity.

Leaf Starch Turnover Occurs in Long Days and in Falling Light at the End of the Day1[OPEN

PubMed Central

Mengin, Virginie; Arrivault, Stéphanie

2017-01-01

We investigated whether starch degradation occurs at the same time as starch synthesis in Arabidopsis (Arabidopsis thaliana) leaves in the light. Starch accumulated in a linear fashion for about 12 h after dawn, then accumulation slowed and content plateaued. Following decreases in light intensity, the rate of accumulation of starch declined in proportion to the decline in photosynthesis if the decrease occurred <10 h after dawn, but accumulation ceased or loss of starch occurred if the same decrease in light intensity was imposed more than 10 h after dawn. These changes in starch accumulation patterns after prolonged periods in the light occurred at both high and low starch contents and were not related to time-dependent changes in either the rate of photosynthesis or the partitioning of assimilate between starch and Suc, as assessed from metabolite measurements and 14CO2 pulse experiments. Instead, measurements of incorporation of 13C from 13CO2 into starch and of levels of the starch degradation product maltose showed that substantial starch degradation occurred simultaneously with synthesis at time points >14 h after dawn and in response to decreases in light intensity that occurred >10 h after dawn. Starch measurements in circadian clock mutants suggested that the clock influences the timing of onset of degradation. We conclude that the propensity for leaf starch to be degraded increases with time after dawn. The importance of this phenomenon for efficient use of carbon for growth in long days and for prevention of starvation during twilight is discussed. PMID:28663333

Evaluation of conditioning time and temperature on gelatinized starch and vitamin retention in a pelleted swine diet.

PubMed

Lewis, L L; Stark, C R; Fahrenholz, A C; Bergstrom, J R; Jones, C K

2015-02-01

Two key feed processing parameters, conditioning temperature and time, were altered to determine their effects on concentration of gelatinized starch and vitamin retention in a pelleted finishing swine diet. Diet formulation (corn–soybean meal based with 30% distillers dried grains with solubles) was held constant. Treatments were arranged in a 2 × 3 factorial design plus a control with 2 conditioning temperatures (77 vs. 88°C) and 3 conditioner retention times (15, 30, and 60 s). In addition, a mash diet not subjected to conditioning served as a control for a total of 7 treatments. Samples were collected after conditioning but before pelleting (hot mash), after pelleting but before cooling (hot pellet), and after pelleting and cooling (cold pellet) and analyzed for percentage total starch, percentage gelatinized starch, and riboflavin, niacin, and vitamin D3 concentrations. Total percentage starch was increased by greater conditioning temperature (P = 0.041) but not time (P > 0.10), whereas higher temperature and longer time both increased (P < 0.05) percentage gelatinized starch, with increasing time resulting in a linear increase in percentage starch gelatinization (P = 0.013). The interaction between conditioning temperature and time increased percentage gelatinized starch (P = 0.003) but not percentage total starch (P > 0.10). Sample location also affected both percentage total starch and gelatinized starch (P < 0.05), with the greatest increase in percentage gelatinized starch occurring between hot mash and hot pellet samples. As expected, the pelleting process increased percentage gelatinized starch (P = 0.035; 7.3 vs. 11.7% gelatinized starch for hot mash vs. hot pellet samples, respectively), but there was no difference in total starch concentrations (P > 0.10). Finally, neither conditioning temperature nor time affected riboflavin, niacin, or vitamin D3 concentrations (P > 0.10). In summary, both increasing conditioningtemperature and time effect percentage gelatinized starch, but not to the extent of forcing the diet through a pelleting die.

New starch methodology to measure both soluble and insoluble starch

USDA-ARS?s Scientific Manuscript database

Starch is a natural sugarcane juice impurity that greatly influences raw sugar quality and affects factory and refinery processing. Since the advent of the USDA Starch Research method, the mechanisms in which starch concentration and physical form affects sugar crop processing, conversion, and end-g...

Starch poisoning

MedlinePlus

Cooking starch poisoning; Laundry starch poisoning ... Cooking and laundry starch are both made from vegetable products, most commonly: Corn Potatoes Rice Wheat Both are usually considered nonpoisonous (nontoxic), but ...

Starch aerogel beads obtained from inclusion complexes prepared from high amylose starch and sodium palmitate

USDA-ARS?s Scientific Manuscript database

Starch aerogels are a class of low density highly porous renewable materials currently prepared from retrograded starch gels and are of interest for their good surface area, porosity, biocompatibility, and biodegradability. Recently, we have reported on starches containing amylose-fatty acid salt h...

75 FR 879 - National Starch and Chemical Company Specialty Starches Division Including On-Site Leased Workers...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-06

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-62,282] National Starch and Chemical Company Specialty Starches Division Including On-Site Leased Workers From Page Employment, Island... Adjustment Assistance on December 13, 2007, applicable to workers of National Starch and Chemical Company...

40 CFR 406.100 - Applicability; description of the wheat starch and gluten subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... wheat starch and gluten subcategory. 406.100 Section 406.100 Protection of Environment ENVIRONMENTAL... Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten... operations utilizing wheat flour as a raw material for production of wheat starch and gluten (protein...

21 CFR 178.3520 - Industrial starch-modified.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Industrial starch-modified. 178.3520 Section 178... § 178.3520 Industrial starch-modified. Industrial starch-modified may be safely used as a component of..., transporting, or holding food, subject to the provisions of this section. (a) Industrial starch-modified is...

Some rheological properties of sodium caseinate-starch gels.

PubMed

Bertolini, Andrea C; Creamer, Lawrence K; Eppink, Mieke; Boland, Mike

2005-03-23

The influence of sodium caseinate on the thermal and rheological properties of starch gels at different concentrations and from different botanical sources was evaluated. In sodium caseinate-starch gels, for all starches with the exception of potato starch, the sodium caseinate promoted an increase in the storage modulus and in the viscosity of the composite gel when compared with starch gels. The addition of sodium caseinate resulted in an increase in the onset temperature, the gelatinization temperature, and the end temperature, and there was a significant interaction between starch and sodium caseinate for the onset temperature, the peak temperature, and the end temperature. Microscopy results suggested that sodium caseinate promoted an increase in the homogeneity in the matrix of cereal starch gels.

THE RESEARCH ON THERMAL PROPERTIES AND HYDROPHOBILITY OF THE NATIVE STARCH/HYDROLYSIS STARCH BLENDS WITH TREATED CaCO{sub 3} POWDER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, C.-I; Huang, C.-Y.

In this research, hydrolysis starch was added into the starch blends to study the thermal properties. The enthalpy of blends had a significant decrease to 109J/g as content of treated CaCO{sub 3} increased to 5wt%. The modified starch was degraded slightly to produce glucose in the hydrolysis treatment. The amount of glucose in native starch and hydrolysis starch was 0.09 {mu}mol and 0.14 {mu}mol by the DNS measurement. Moreover, CaCO{sub 3} treated with titanium coupling agent was also added to improve miscibility and hydrophobility in the starch blends. The contact angle of the blends increased from 60 deg. to 95more » deg. when 15wt% treated CaCO{sub 3} was added. Treated CaCO{sub 3} was confirmed to improve the hydrophobility of starch blends effectively.« less

Imidazole-based deep eutectic solvents for starch dissolution and plasticization.

PubMed

Zdanowicz, Magdalena; Spychaj, Tadeusz; Mąka, Honorata

2016-04-20

Potato starch and high-amylose starch were treated with imidazole-based deep eutectic solvents (DESs) as dissolution and plasticization media. Beside imidazole (IM) for two-component DESs preparation choline chloride (CC), glycerol (G) or carboxylic acids (citric or malic) were used. An influence of water content in starch (as well as an extra water in the starch/DES system) on polymer dissolution and plasticization processes was investigated. Dissolution and gelatinization of starch in DESs were followed via DSC and laser scanning microscopy. A rheometric characteristics revealed an influence of starch/DES system storage time on the plasticization process. The tendency to recrystallization of compression-molded-starch films was evaluated using XRD technique. High dissolution and plasticization effectiveness of CC/IM and G/IM and a low tendency to film retrogradation of thermoplasticized starch were noted. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of Microwave Irradiation on the Physicochemical and Digestive Properties of Lotus Seed Starch.

PubMed

Zeng, Shaoxiao; Chen, Bingyan; Zeng, Hongliang; Guo, Zebin; Lu, Xu; Zhang, Yi; Zheng, Baodong

2016-03-30

The objective of this study is to investigate the effect of microwave irradiation on the physicochemical and digestive properties of lotus seed starch. The physicochemical properties of lotus seed starch were characterized by light microscopy, (1)H NMR, FT-IR spectroscopy, and HPSEC-MALLS-RI. The starch-water interaction and crystalline region increased due to the changed water distribution of starch granules and the increase of the double-helix structure. The swelling power, amylose leaching, molecular properties, and radius of gyration reduced with the increasing microwave power, which further affected the sensitivity of lotus seed starch to enzymatic degradation. Furthermore, the resistant starch and slowly digestible starch increased with the increasing microwave irradiation, which further resulted in their decreasing hydrolysis index and glycemic index. The digestive properties of lotus seed starch were mainly influenced by the reduced branching degree of amylopectin and the strong amylose-amylose interaction.

Insights into the hierarchical structure and digestion rate of alkali-modulated starches with different amylose contents.

PubMed

Qiao, Dongling; Yu, Long; Liu, Hongsheng; Zou, Wei; Xie, Fengwei; Simon, George; Petinakis, Eustathios; Shen, Zhiqi; Chen, Ling

2016-06-25

Combined analytical techniques were used to explore the effects of alkali treatment on the multi-scale structure and digestion behavior of starches with different amylose/amylopectin ratios. Alkali treatment disrupted the amorphous matrix, and partial lamellae and crystallites, which weakened starch molecular packing and eventually enhanced the susceptibility of starch to alkali. Stronger alkali treatment (0.5% w/w) made this effect more prominent and even transformed the dual-phase digestion of starch into a triple-phase pattern. Compared with high-amylose starch, regular maize starch, which possesses some unique structure characteristics typically as pores and crystallite weak points, showed evident changes of hierarchical structure and in digestion rate. Thus, alkali treatment has been demonstrated as a simple method to modulate starch hierarchical structure and thus to realize the rational development of starch-based food products with desired digestibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion

PubMed Central

Crumpton-Taylor, Matilda; Pike, Marilyn; Lu, Kuan-Jen; Hylton, Christopher M; Feil, Regina; Eicke, Simona; Lunn, John E; Zeeman, Samuel C; Smith, Alison M

2013-01-01

Arabidopsis thaliana mutants lacking the SS4 isoform of starch synthase have strongly reduced numbers of starch granules per chloroplast, suggesting that SS4 is necessary for the normal generation of starch granules. To establish whether it plays a direct role in this process, we investigated the circumstances in which granules are formed in ss4 mutants. Starch granule numbers and distribution and the accumulation of starch synthase substrates and products were investigated during ss4 leaf development, and in ss4 mutants carrying mutations or transgenes that affect starch turnover or chloroplast volume. We found that immature ss4 leaves have no starch granules, but accumulate high concentrations of the starch synthase substrate ADPglucose. Granule numbers are partially restored by elevating the capacity for glucan synthesis (via expression of bacterial glycogen synthase) or by increasing the volumes of individual chloroplasts (via introduction of arc mutations). However, these granules are abnormal in distribution, size and shape. SS4 is an essential component of a mechanism that coordinates granule formation with chloroplast division during leaf expansion and determines the abundance and the flattened, discoid shape of leaf starch granules. PMID:23952675

Physical and mechanical properties of LDPE incorporated with different starch sources

NASA Astrophysics Data System (ADS)

Kormin, Shaharuddin; Kormin, Faridah; Dalour Hossen Beg, Mohammad; Bijarimi Mat Piah, Mohd

2017-08-01

In this study it was investigated the incorporation of different starches, such as sago starch, corn starch, potato starch, tapioca starch and wheat starch, in low-density polyethylene matrix (LDPE) to enhanced mechanical properties and to obtain partially biodegradable product with the aim to reduce the plastics wastes in the environment. For comparison, virgin LDPE, LDPE with different sources of starch blends were prepared and characterized under the same conditions. The starches were mixed to the LDPE using a twin screw extruder to guarantee the homogeneity of the formulations. The compound were shaping processed by injection moulding. The characterization of those compounds was done by physical (density, MFI), mechanical (Universal tensile machine). The addition of starch to LDPE reduced the MFI values, the tensile strength, elongation at break and impact strength, whereas the elastic modulus, flexural modulus and flexural strength increased. LDPE/SS show the good mechanical behavior compared to other formulation. The physical and mechanical properties were evident when 5 and 30 wt% were added. Water uptake increased with increased starch content and immersion time. The time taken for the composites to equilibrate was about one month even when they were immersed completely in water.

Characters related to higher starch accumulation in cassava storage roots

PubMed Central

Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

2016-01-01

Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

Characters related to higher starch accumulation in cassava storage roots.

PubMed

Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

2016-02-19

Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

Structural properties of hydrolyzed high-amylose rice starch by α-amylase from Bacillus licheniformis.

PubMed

Qin, Fengling; Man, Jianmin; Xu, Bin; Hu, Maozhi; Gu, Minghong; Liu, Qiaoquan; Wei, Cunxu

2011-12-14

High-amylose cereal starch has a great benefit on human health through its resistant starch (RS) content. Enzyme hydrolysis of native starch is very helpful in understanding the structure of starch granules and utilizing them. In this paper, native starch granules were isolated from a transgenic rice line (TRS) enriched with amylose and RS and hydrolyzed by α-amylase. Structural properties of hydrolyzed TRS starches were studied by X-ray powder diffraction, Fourier transform infrared, and differential scanning calorimetry. The A-type polymorph of TRS C-type starch was hydrolyzed faster than the B-type polymorph, but the crystallinity did not significantly change during enzyme hydrolysis. The degree of order in the external region of starch granule increased with increasing enzyme hydrolysis time. The amylose content decreased at first and then went back up during enzyme hydrolysis. The hydrolyzed starches exhibited increased onset and peak gelatinization temperatures and decreased gelatinization enthalpy on hydrolysis. These results suggested that the B-type polymorph and high amylose that formed the double helices and amylose-lipid complex increased the resistance to BAA hydrolysis. Furthermore, the spectrum results of RS from TRS native starch digested by pancreatic α-amylase and amyloglucosidase also supported the above conclusion.

Physicochemical properties, in-vitro digestibility and structural elucidation of RS4 from rice starch.

PubMed

Ashwar, Bilal Ahmad; Gani, Adil; Shah, Asima; Masoodi, Farooq Ahmad

2017-12-01

Starches extracted from four different rice cultivars were phosphorylated by using STMP/STPP to make modified food starches with high contents of type 4 resistant starch (RS4). The results revealed 10- fold improvement in RS4 content by the phosphorylation of starch. The phosphorus % and DS values of rice starches ranged from 0.33 to 0.35, and 0.016 to 0.018, respectively. FT-IR spectroscopy showed reduction of OH stretching band at 3290cm-1 and the appearance of PO at 1244-1266cm-1 which confirms crosslinking of starch with STMP/STPP. Phosphorylation was found to increase water absorption capacity, oil absorption capacity, bile-acid binding and lightness, whereas amylose content, swelling power, solubility index and light transmittance were decreased with phosphorylation. DSC analyses revealed increase in thermal transition temperatures of the crosslinked starches which suggests that the application of STMP/STPP as a crosslinker can improve the integrality and stability of starch. SEM micro-graphs revealed that phosphorylated rice starch granules retained their integrity, while some fissures appeared on the surface of some granules. XRD analysis revealed decreased crystallinity of RS4 rice starches. Copyright © 2017 Elsevier B.V. All rights reserved.

Amylopectin molecular structure reflected in macromolecular organization of granular starch.

PubMed

Vermeylen, Rudi; Goderis, Bart; Reynaers, Harry; Delcour, Jan A

2004-01-01

For lintners with negligible amylose retrogradation, crystallinity related inversely to starch amylose content and, irrespective of starch source, incomplete removal of amorphous material was shown. The latter was more pronounced for B-type than for A-type starches. The two predominant lintner populations, with modal degrees of polymerization (DP) of 13-15 and 23-27, were best resolved for amylose-deficient and A-type starches. Results indicate a more specific hydrolysis of amorphous lamellae in such starches. Small-angle X-ray scattering showed a more intense 9-nm scattering peak for native amylose-deficient A-type starches than for their regular or B-type analogues. The experimental evidence indicates a lower contrasting density within the "crystalline" shells of the latter starches. A higher density in the amorphous lamellae, envisaged by the lamellar helical model, explains the relative acid resistance of linear amylopectin chains with DP > 20, observed in lintners of B-type starches. Because amylopectin chain length distributions were similar for regular and amylose-deficient starches of the same crystal type, we deduce that the more dense (and ordered) packing of double helices into lamellar structures in amylose-deficient starches is due to a different amylopectin branching pattern.

Starch Characteristics Linked to Gluten-Free Products.

PubMed

Horstmann, Stefan W; Lynch, Kieran M; Arendt, Elke K

2017-04-06

The increasing prevalence of coeliac disease (CD) and gluten-related disorders has led to increasing consumer demand for gluten-free products with quality characteristics similar to wheat bread. The replacement of gluten in cereal-based products remains a challenge for scientists, due to its unique role in network formation, which entraps air bubbles. When gluten is removed from a flour, starch is the main component left. Starch is used as gelling, thickening, adhesion, moisture-retention, stabilizing, film forming, texturizing and anti-staling ingredient. The extent of these properties varies depending on the starch source. The starches can additionally be modified increasing or decreasing certain properties of the starch, depending on the application. Starch plays an important role in the formulation of bakery products and has an even more important role in gluten-free products. In gluten-free products, starch is incorporated into the food formulation to improve baking characteristics such as the specific volume, colour and crumb structure and texture. This review covers a number of topics relating to starch; including; an overview of common and lesser researched starches; chemical composition; morphology; digestibility; functionality and methods of modification. The emphasis of this review is on starch and its properties with respect to the quality of gluten-free products.

Rheological Properties and Electrospinnability of High-Amylose Starch in Formic Acid.

PubMed

Lancuški, Anica; Vasilyev, Gleb; Putaux, Jean-Luc; Zussman, Eyal

2015-08-10

Starch derivatives, such as starch-esters, are commonly used as alternatives to pure starch due to their enhanced mechanical properties. However, simple and efficient processing routes are still being sought out. In the present article, we report on a straightforward method for electrospinning high-amylose starch-formate nanofibers from 17 wt % aqueous formic acid (FA) dispersions. The diameter of the electrospun starch-formate fibers ranged from 80 to 300 nm. The electrospinnability window between starch gelatinization and phase separation was determined using optical microscopy and rheological studies. This window was shown to strongly depend on the water content in the FA dispersions. While pure FA rapidly gelatinized starch, yielding solutions suitable for electrospinning within a few hours at room temperature, the presence of water (80 and 90 vol % FA) significantly delayed gelatinization and dissolution, which deteriorated fiber quality. A complete destabilization of the electrospinning process was observed in 70 vol % FA dispersions. Optical micrographs showed that FA induced a disruption of starch granule with a loss of crystallinity confirmed by X-ray diffraction. As a result, starch fiber mats exhibited a higher elongation at break when compared to brittle starch films.

The Phosphoglucan Phosphatase Like Sex Four2 Dephosphorylates Starch at the C3-Position in Arabidopsis[W][OA

PubMed Central

Santelia, Diana; Kötting, Oliver; Seung, David; Schubert, Mario; Thalmann, Matthias; Bischof, Sylvain; Meekins, David A.; Lutz, Andy; Patron, Nicola; Gentry, Matthew S.; Allain, Frédéric H.-T.; Zeeman, Samuel C.

2011-01-01

Starch contains phosphate covalently bound to the C6-position (70 to 80% of total bound phosphate) and the C3-position (20 to 30%) of the glucosyl residues of the amylopectin fraction. In plants, the transient phosphorylation of starch renders the granule surface more accessible to glucan hydrolyzing enzymes and is required for proper starch degradation. Phosphate also confers desired properties to starch-derived pastes for industrial applications. In Arabidopsis thaliana, the removal of phosphate by the glucan phosphatase Starch Excess4 (SEX4) is essential for starch breakdown. We identified a homolog of SEX4, LSF2 (Like Sex Four2), as a novel enzyme involved in starch metabolism in Arabidopsis chloroplasts. Unlike SEX4, LSF2 does not have a carbohydrate binding module. Nevertheless, it binds to starch and specifically hydrolyzes phosphate from the C3-position. As a consequence, lsf2 mutant starch has elevated levels of C3-bound phosphate. SEX4 can release phosphate from both the C6- and the C3-positions, resulting in partial functional overlap with LSF2. However, compared with sex4 single mutants, the lsf2 sex4 double mutants have a more severe starch-excess phenotype, impaired growth, and a further change in the proportion of C3- and C6-bound phosphate. These findings significantly advance our understanding of the metabolism of phosphate in starch and provide innovative options for tailoring novel starches with improved functionality for industry. PMID:22100529

The phosphoglucan phosphatase like sex Four2 dephosphorylates starch at the C3-position in Arabidopsis.

PubMed

Santelia, Diana; Kötting, Oliver; Seung, David; Schubert, Mario; Thalmann, Matthias; Bischof, Sylvain; Meekins, David A; Lutz, Andy; Patron, Nicola; Gentry, Matthew S; Allain, Frédéric H-T; Zeeman, Samuel C

2011-11-01

Starch contains phosphate covalently bound to the C6-position (70 to 80% of total bound phosphate) and the C3-position (20 to 30%) of the glucosyl residues of the amylopectin fraction. In plants, the transient phosphorylation of starch renders the granule surface more accessible to glucan hydrolyzing enzymes and is required for proper starch degradation. Phosphate also confers desired properties to starch-derived pastes for industrial applications. In Arabidopsis thaliana, the removal of phosphate by the glucan phosphatase Starch Excess4 (SEX4) is essential for starch breakdown. We identified a homolog of SEX4, LSF2 (Like Sex Four2), as a novel enzyme involved in starch metabolism in Arabidopsis chloroplasts. Unlike SEX4, LSF2 does not have a carbohydrate binding module. Nevertheless, it binds to starch and specifically hydrolyzes phosphate from the C3-position. As a consequence, lsf2 mutant starch has elevated levels of C3-bound phosphate. SEX4 can release phosphate from both the C6- and the C3-positions, resulting in partial functional overlap with LSF2. However, compared with sex4 single mutants, the lsf2 sex4 double mutants have a more severe starch-excess phenotype, impaired growth, and a further change in the proportion of C3- and C6-bound phosphate. These findings significantly advance our understanding of the metabolism of phosphate in starch and provide innovative options for tailoring novel starches with improved functionality for industry.

Impact of the Soak and the Malt on the Physicochemical Properties of the Sorghum Starches

PubMed Central

Claver, Irakoze Pierre; Zhang, Haihua; Li, Qin; Zhu, Kexue; Zhou, Huiming

2010-01-01

Starches were isolated from soaked and malted sorghum and studied to understand their physicochemical and functional properties. The swelling power (SP) and the water solubility index (WSI) of both starches were nearly similar at temperatures below 50 °C, but at more than 50 °C, the starch isolated from malted sorghum showed lower SP and high WSI than those isolated from raw and soaked sorghum. The pasting properties of starches determined by rapid visco-analyzer (RVA) showed that malted sorghum starch had a lower viscosity peak value (86 BU/RVU) than raw sorghum starch (454 BU/RVU). For both sorghum, X-ray diffractograms exhibited an A-type diffraction pattern, typical of cereal starches and the relative degrees of crystallinity ranged from 9.62 to 15.50%. Differential scanning calorimetry (DSC) revealed that raw sorghum starch showed an endotherm with a peak temperature (Tp) at 78.06 °C and gelatinization enthalpies of 2.83 J/g whereas five-day malted sorghum starch had a Tp at 47.22 °C and gelatinization enthalpies of 2.06 J/g. Storage modulus (G′) and loss modulus (G″) of all starch suspensions increased steeply to a maximum at 70 °C and then decreased with continuous heating. The structural analysis of malted sorghum starch showed porosity on the granule’s surface susceptible to the amylolysis. The results showed that physicochemical and functional properties of sorghum starches are influenced by soaking and malting methods. PMID:21152287

Role of Orthophosphate and Other Factors in the Regulation of Starch Formation in Leaves and Isolated Chloroplasts

PubMed Central

Heldt, Hans W.; Chon, Chong Ja; Maronde, Dorothea; Herold, Alice; Stankovic, Zivko S.; Walker, David A.; Kraminer, Anna; Kirk, Martha R.; Heber, Ulrich

1977-01-01

Starch synthesis in leaves was increased by phosphate starvation or by treatments which decreased cytoplasmic orthophosphate levels (such as mannose feeding). Usually less than 30% of the total carbon fixed during CO2 assimilation was incorporated into starch in spinach (Spinacia oleracea L.), spinach beet (Beta vulgaris), and tobacco (Nicotiana tabacum) leaves. In isolated spinach chloroplasts, formation of starch from CO2 was usually less than in leaves. In the absence of significant levels of 3-phosphoglycerate, concentrations of phosphate as low as 1 mm (in the medium) or 10 mm (in the stroma) almost completely inhibited starch synthesis. The inhibitory action of phosphate could be overcome by 3-phosphoglycerate. The controlling factor of starch synthesis appeared to be the ratio of phosphoglycerate to orthophosphate rather than the stromal hexose monophosphate concentration, and it is suggested that this control is exerted via the phosphate translocator and the known allosteric regulation of ADP-glucose pyrophosphorylase. Starch synthesis was also favored by the presence of dihydroxyacetone phosphate and by high light and high temperature. Oxygen was inhibitory, probably owing to carbon drain into glycolate. Starch formation by intact chloroplasts could not be promoted by added glucose or glucose 6-phosphate. Starch mobilization in the dark was promoted by orthophosphate and phosphate-dependent mobilization was inhibited by phosphoglycerate. The principal products of starch breakdown in the presence of phosphate were the transport metabolites dihydroxyacetone phosphate and 3-phosphoglycerate. Formation of these compounds from starch was stimulated by ATP or oxaloacetate. In a phosphate-independent reaction, starch was also converted to neutral products such as maltose and glucose. The rates of phosphate-dependent starch degradation phosphorolysis were very much higher than those of starch hydrolysis for which there was no phosphate requirement. PMID:16660011

Two- and multi-step annealing of cereal starches in relation to gelatinization.

PubMed

Shi, Yong-Cheng

2008-02-13

Two- and multi-step annealing experiments were designed to determine how much gelatinization temperature of waxy rice, waxy barley, and wheat starches could be increased without causing a decrease in gelatinization enthalpy or a decline in X-ray crystallinity. A mixture of starch and excess water was heated in a differential scanning calorimeter (DSC) pan to a specific temperature and maintained there for 0.5-48 h. The experimental approach was first to anneal a starch at a low temperature so that the gelatinization temperature of the starch was increased without causing a decrease in gelatinization enthalpy. The annealing temperature was then raised, but still was kept below the onset gelatinization temperature of the previously annealed starch. When a second- or third-step annealing temperature was high enough, it caused a decrease in crystallinity, even though the holding temperature remained below the onset gelatinization temperature of the previously annealed starch. These results support that gelatinization is a nonequilibrium process and that dissociation of double helices is driven by the swelling of amorphous regions. Small-scale starch slurry annealing was also performed and confirmed the annealing results conducted in DSC pans. A three-phase model of a starch granule, a mobile amorphous phase, a rigid amorphous phase, and a crystalline phase, was used to interpret the annealing results. Annealing seems to be an interplay between a more efficient packing of crystallites in starch granules and swelling of plasticized amorphous regions. There is always a temperature ceiling that can be used to anneal a starch without causing a decrease in crystallinity. That temperature ceiling is starch-specific, dependent on the structure of a starch, and is lower than the original onset gelatinization of a starch.

Evaluation of a High Throughput Starch Analysis Optimised for Wood

PubMed Central

Bellasio, Chandra; Fini, Alessio; Ferrini, Francesco

2014-01-01

Starch is the most important long-term reserve in trees, and the analysis of starch is therefore useful source of physiological information. Currently published protocols for wood starch analysis impose several limitations, such as long procedures and a neutralization step. The high-throughput standard protocols for starch analysis in food and feed represent a valuable alternative. However, they have not been optimised or tested with woody samples. These have particular chemical and structural characteristics, including the presence of interfering secondary metabolites, low reactivity of starch, and low starch content. In this study, a standard method for starch analysis used for food and feed (AOAC standard method 996.11) was optimised to improve precision and accuracy for the analysis of starch in wood. Key modifications were introduced in the digestion conditions and in the glucose assay. The optimised protocol was then evaluated through 430 starch analyses of standards at known starch content, matrix polysaccharides, and wood collected from three organs (roots, twigs, mature wood) of four species (coniferous and flowering plants). The optimised protocol proved to be remarkably precise and accurate (3%), suitable for a high throughput routine analysis (35 samples a day) of specimens with a starch content between 40 mg and 21 µg. Samples may include lignified organs of coniferous and flowering plants and non-lignified organs, such as leaves, fruits and rhizomes. PMID:24523863

Physicochemical, morphological, and rheological characterization of Xanthosoma robustum Lego-like starch.

PubMed

Londoño-Restrepo, Sandra M; Rincón-Londoño, Natalia; Contreras-Padilla, Margarita; Acosta-Osorio, Andrés A; Bello-Pérez, Luis A; Lucas-Aguirre, Juan C; Quintero, Víctor D; Pineda-Gómez, Posidia; del Real-López, Alicia; Rodríguez-García, Mario E

2014-04-01

This work presents the physicochemical and pasting characterization of isolated mafafa starch and mafafa flour (Xanthosoma robustum). According to SEM images of mafafa starches in the tuber, these starches form Lego-like shaped structures with diameters between 8 and 35 μm conformed by several starch granules of wedge shape that range from 2 to 7 μm. The isolated mafafa starch is characterized by its low contents of protein, fat, and ash. The starch content in isolated starch was found to be 88.58% while the amylose content obtained was 35.43%. X-ray diffraction studies confirm that isolated starch is composed mainly by amylopectin. These results were confirmed by differential scanning calorimetry and thermo gravimetric analysis. This is the first report of the molecular parameters for mafafa starch: molar mass that ranged between 2×10(8) and 4×10(8) g/mol, size (Rg) value between 279 and 295 nm, and molecular density value between 9.2 and 9.7 g/(mol nm(3)). This study indicates that mafafa starch shows long chains of amylopectin this fact contributes to higher viscosity development and higher gel stability. The obtained gel phase is transparent in the UV-vis region. The viscosity, gel stability and optical properties suggest that there is potential for mafafa starch applications in the food industry. Copyright © 2014 Elsevier B.V. All rights reserved.

Chemical composition and functional properties of native chestnut starch (Castanea sativa Mill).

PubMed

Cruz, Bruno R; Abraão, Ana S; Lemos, André M; Nunes, Fernando M

2013-04-15

Starch isolation methods can change their physico-chemical and functional characteristics hindering the establishment of a starch-food functionality relation. A simple high yield and soft isolation method was applied for chestnut (Castanea sativa Mill) starch consisting in steeping and fruit disintegration in a 25 mM sodium bisulfite solution and purification by sedimentation. Starch integrity, physico-chemical composition, morphology and functional properties were determined, being observed significant differences from previous described methods for chestnut starch isolation. The X-ray pattern was of B-type, with a degree of crystallinity ranging from 51% to 9%, dependent on the starch moisture content. The onset, peak, and conclusion gelatinization temperatures were 57.1°C, 61.9°C and 67.9°C, respectively. Total amylose content was 26.6%, and there was not found any evidence for lipid complexed amylose. Swelling power at 90°C was 19 g/g starch, and the amount of leached amylose was 78% of the total amylose content. Native chestnut starch presents a type B pasting profile similar to corn starch but with a lower gelatinization (56.1°C) and peak viscosity (79.5°C) temperatures, making native chestnut starch a potential technological alternative to corn starch, especially in application where lower processing temperatures are needed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of citric acid concentration and hydrolysis time on physicochemical properties of sweet potato starches.

PubMed

Surendra Babu, Ayenampudi; Parimalavalli, Ramanathan; Rudra, Shalini Gaur

2015-09-01

Physicochemical properties of citric acid treated sweet potato starches were investigated in the present study. Sweet potato starch was hydrolyzed using citric acid with different concentrations (1 and 5%) and time periods (1 and 11 h) at 45 °C and was denoted as citric acid treated starch (CTS1 to CTS4) based on their experimental conditions. The recovery yield of acid treated starches was above 85%. The CTS4 sample displayed the highest amylose (around 31%) and water holding capacity its melting temperature was 47.66 °C. The digestibility rate was slightly increased for 78.58% for the CTS3 and CTS4. The gel strength of acid modified starches ranged from 0.27 kg to 1.11 kg. RVA results of acid thinned starches confirmed a low viscosity profile. CTS3 starch illustrated lower enthalpy compared to all other modified starches. All starch samples exhibited a shear-thinning behavior. SEM analysis revealed that the extent of visible degradation was increased at higher hydrolysis time and acid concentration. The CTS3 satisfied the criteria required for starch to act as a fat mimetic. Overall results conveyed that the citric acid treatment of sweet potato starch with 5% acid concentration and 11h period was an ideal condition for the preparation of a fat replacer. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of dietary starch source and concentration on equine fecal microbiota

USDA-ARS?s Scientific Manuscript database

Starch from corn is less susceptible to equine small intestinal digestion than starch from oats, and starch that reaches the hindgut can be utilized by the microbiota. The objective of the current study was to examine the effects of starch source on equine fecal microbiota. Thirty horses were assig...

Spectroscopic, calorimetric and structural analyses of the effects of hydrothermal treatment of rice beans and the extraction solvent on starch characteristics.

PubMed

González-Cruz, Leopoldo; Montañez-Soto, José Luis; Conde-Barajas, Eloy; Negrete-Rodríguez, María de la Luz Xochilt; Flores-Morales, Areli; Bernardino-Nicanor, Aurea

2018-02-01

The modification of the starches extracted from rice beans both with and without hydrothermal treatment was evaluated via scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared (FT-IR) and Raman spectroscopy. SEM indicated that the starch granules of rice beans exhibit wide variation in granule shape, showing the greatest size and modification of the surface when extracted with ethanol. It was found that the extraction solvent had no significant effect on the onset (T o ) and peak (T p ) temperatures of the starch, whereas hydrothermal treatment of rice beans decreased the T o , T p and ΔH of the starch. The modification of FT-IR spectra showed that hydrothermal treatment of rice beans and the solvent used in the extraction of starch affected starch crystallinity, mainly when ethanol was used. Raman spectroscopy revealed that the smaller changes in the starch bonds were due to the solvent used for starch extraction but that hydrothermal treatment disturbed all bonds in the starch. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation and characterization of resistant starch III from elephant foot yam (Amorphophallus paeonifolius) starch.

PubMed

Reddy, Chagam Koteswara; Haripriya, Sundaramoorthy; Noor Mohamed, A; Suriya, M

2014-07-15

The purpose of this study was to assess the properties of resistant starch (RS) III prepared from elephant foot yam starch using pullulanase enzyme. Native and gelatinized starches were subjected to enzymatic hydrolysis (pullulanase, 40 U/g per 10h), autoclaved (121°C/30 min), stored under refrigeration (4°C/24h) and then lyophilized. After preparation of resistant starch III, the morphological, physical, chemical and functional properties were assessed. The enzymatic and retrogradation process increased the yield of resistant starch III from starch with a concomitant increase increase in its water absorption capacity and water solubility index. A decrease in swelling power was observed due to the hydrolysis and thermal process. Te reduced pasting properties and hardness of resistant starch III were associated with the disintegration of starch granules due to the thermal process. The viscosity was found to be inversely proportional to the RS content in the sample. The thermal properties of RS increased due to retrogradation and recrystallization (P<0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of Multiple Freezing/Thawing Cycles on the Structural and Functional Properties of Waxy Rice Starch

PubMed Central

Tao, Han; Yan, Juan; Zhao, Jianwei; Tian, Yaoqi; Jin, Zhengyu; Xu, Xueming

2015-01-01

The structural and functional properties of non-gelatinized waxy rice starch were investigated after 1, 3, 7, and 10 freezing/thawing cycles. Freezing caused an increasing damaged starch from 1.36% in native waxy rice starch to 5.77% in 10 freezing/thawing-treated starch (FTS), as evidenced by the cracking surface on starch granules. More dry matter concentration was leached, which was characterized by high amylopectin concentration (4.34 mg/mL). The leaching was accompanied by a decrease in relative crystallinity from 35.19% in native starch to 31.34% in 10 FTS. Freezing treatment also led to significant deviations in the functional characteristics, for instance decreased gelatinization temperature range, enthalpy, and pasting viscosities. The resistant starch content of 10FTS significantly decreased from 58.9% to 19%, whereas the slowly digested starch content greatly increased from 23.8% in native starch to 50.3%. The increase in susceptibility to enzyme hydrolysis may be attributed to porous granular surface, amylopectin leaching, and the decrease in the relative crystallinity caused by freezing water. PMID:26018506

Effect of a small amount of sodium carbonate on konjac glucomannan-induced changes in thermal behavior of wheat starch.

PubMed

Zhou, Yun; Winkworth-Smith, Charles G; Wang, Yu; Liang, Jianfen; Foster, Tim J; Cheng, Yongqiang

2014-12-19

The effects of konjac glucomannan (KGM) on thermal behavior of wheat starch have been studied in the presence of low concentrations of Na2CO3 (0.1-0.2 wt% of starch). Confocal laser scanning microscopy (CLSM) allows the visualization of the starch gelatinization process and granule remnants in starch pastes. Heating the starch dispersion in KGM-Na2CO3 solution significantly delays granule swelling and inhibits amylose leaching, whereas Na2CO3 alone, at the same concentration, has little effect. Na2CO3 assists KGM in producing the extremely high viscosity of starch paste, attributing to a less remarkable breakdown of viscosity in subsequent heating, and protecting starch granules against crystallite melting. The distinct partially networked film around the surface of starch granules is evident in the CLSM images. We propose that Na2CO3 could trigger the formation of complexes between KGM and starch polymers, which exerts a protective effect on granular structure and modifying gelatinization characteristics of the mixtures. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of roasted pea flour/starch and encapsulated pea starch incorporation on the in vitro starch digestibility of pea breads.

PubMed

Lu, Zhan-Hui; Donner, Elizabeth; Liu, Qiang

2018-04-15

Oven or microwave roasting and alginate encapsulation of pea flour and starch to produce novel pea ingredients for enrichment of slowly digestible starch (SDS) and resistant starch (RS) content in pea bread were investigated. Pea flour treated either by oven roasting (160°C, 30min) or by microwave roasting (1.1kW, 6min) effectively retained its low starch digestibility similar to its native form (∼25% SDS; ∼60% RS). When oven roasting was applied to pea starch, SDS content increased triply compared to the fully boiled counterpart. Alginate encapsulation effectively controlled carbohydrate release to simulated gastric, intestinal and colonic fluids, and thus largely enriched the SDS and RS fractions in starch. Pea bread containing up to 37.5% of encapsulated roasted MPS pea starch not only provided high SDS and RS fractions (23.9% SDS and 30.2% RS) compared to a white bread control (0.2% SDS and 2.5% RS), but also provided an acceptable palatability. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

PubMed

Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

2014-10-01

The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

Transesterification of sago starch and waste palm cooking oil in densified CO2

NASA Astrophysics Data System (ADS)

Muljana, H.; Sugih, A. K.; Christina, N.; Fangdinata, K.; Renaldo, J.; Rudy; Heeres, H. J.; Picchioni, F.

2017-07-01

In this work, the synthesis of biodegradable and yet renewable thermoplastics materials through a transesterification reaction of sago starch and waste palm cooking oil (WPO) in densified CO2 as the solvent is reported. The aim of this research is to investigate the potential used of sago starch and WPO as raw materials in the thermoplastics starch synthesis. The starch esters was successfully synthesized using sago starch and WPO as reagent in densified CO2 as shown from the presence of carbonyl group (C=O, 1743 cm-1) in the FT-IR spectra coupled with the presence of the proton (1H-NMR) of the fatty acid in the starch backbone (0.8 - 2 ppm). The product crystallinity decreases as shown in XRD results and resulting with a change in the thermal properties (melting and crystalline temperature) of the products. In addition, the products show a different granular morphology and a higher hydrophobicity compared with native sago starch. This research shows the potential used of sago starch and WPO in the thermoplastics starch synthesis and opens a new perspective on the product application.

Effect of molecular weight of starch on the properties of cassava starch microspheres prepared in aqueous two-phase system.

PubMed

Xia, Huiping; Li, Bing-Zheng; Gao, Qunyu

2017-12-01

Starch microspheres (SMs) were fabricated in an aqueous two-phase system (ATPS). A series of starch samples with different molecular weight were prepared by acid hydrolysis, and the effect of molecular weight of starch on the fabrication of SMs were investigated. Scanning electron microscopy (SEM) showed that the morphologies of SMs varied with starch molecular weight, and spherical SMs with sharp contours were obtained while using starch samples with weight-average molecular weight (M¯w)≤1.057×10 5 g/mol. X-ray diffraction (XRD) results revealed that crystalline structure of SMs were different from that of native cassava starch, and the relative crystallinity of SMs increased with the molecular weight of starch decreasing. Differential scanning calorimetry (DSC) results showed peak gelatinization temperature (T p ) and enthalpy of gelatinization (ΔH) of SMs increased with decreased M¯wof starch. Stability tests indicated that the SMs were stable under acid environment, but not stable under α-amylase hydrolysis. Copyright © 2017. Published by Elsevier Ltd.

Do starch statoliths act as the gravisensors in cereal grass pulvini?

NASA Technical Reports Server (NTRS)

Song, I.; Lu, C. R.; Brock, T. G.; Kaufman, P. B.

1988-01-01

To determine if starch statoliths do, in fact, act as gravisensors in cereal grass shoots, starch was removed from the starch statoliths by placing 45-day-old intact barley plants (Hordeum vulgare cv 'Larker') in the dark at 25 degrees C for 5 days. Evidence from staining with I2-KI, scanning electron microscopy, and transmission electron microscopy indicated that starch grains were no longer present in plastids in the pulvini of plants placed in the dark for 5 days. Furthermore, gravitropic curvature response in these pulvini was reduced to zero, even though pulvini from vertically oriented plants were still capable of elongating in response to applied auxin plus gibberellic acid. However, when 0.1 molar sucrose was fed to the dark pretreated, starch statolith-free pulvini during gravistimulation in the dark, they not only reformed starch grains in the starch-depleted plastids in the pulvini, but they also showed an upward bending response. Starch grain reformation appeared to precede reappearance of the graviresponse in these sucrose-fed pulvini. These results strongly support the view that starch statoliths do indeed serve as the gravisensors in cereal grass shoots.

Preparation and characterization of non-crystalline granular starch and corresponding carboxymethyl starch.

PubMed

Zhang, Bao; Li, Xiaomin; Xie, Qiutao; Tao, Han; Wang, Wu; Chen, Han-Qing

2017-10-01

Native corn starch slurried in 50% ethanol solution was treated at 60°C, 70°C, 80°C, and 85°C, respectively. The resultant starches were investigated by polarized microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffractometry (XRD). The Maltese cross of ethanol-heating treated starch gradually weaken with increasing temperature and completely disappeared at 85°C. SEM data indicated the treated granular exhibited a rougher surface with more pores and grooves than native starch granular, but the shape of the treated starch was still intact. DSC and XRD data confirmed ethanol-heating treated starch changed from crystalline to non-crystalline structure at 85°C. The highest degree of substitution (DS) and corresponding reaction efficiency (RE) for the carboxymethylation of native starch were 0.66 and 36.7%, respectively, while the corresponding DS and RE for non-crystalline granular starches increased by 0.29 and 16.1% at the same reaction condition, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of multiple freezing/thawing cycles on the structural and functional properties of waxy rice starch.

PubMed

Tao, Han; Yan, Juan; Zhao, Jianwei; Tian, Yaoqi; Jin, Zhengyu; Xu, Xueming

2015-01-01

The structural and functional properties of non-gelatinized waxy rice starch were investigated after 1, 3, 7, and 10 freezing/thawing cycles. Freezing caused an increasing damaged starch from 1.36% in native waxy rice starch to 5.77% in 10 freezing/thawing-treated starch (FTS), as evidenced by the cracking surface on starch granules. More dry matter concentration was leached, which was characterized by high amylopectin concentration (4.34 mg/mL). The leaching was accompanied by a decrease in relative crystallinity from 35.19% in native starch to 31.34% in 10 FTS. Freezing treatment also led to significant deviations in the functional characteristics, for instance decreased gelatinization temperature range, enthalpy, and pasting viscosities. The resistant starch content of 10FTS significantly decreased from 58.9% to 19%, whereas the slowly digested starch content greatly increased from 23.8% in native starch to 50.3%. The increase in susceptibility to enzyme hydrolysis may be attributed to porous granular surface, amylopectin leaching, and the decrease in the relative crystallinity caused by freezing water.

Effect of high dietary starch levels on growth, hepatic glucose metabolism, oxidative status and immune response of juvenile largemouth bass, Micropterus salmoides.

PubMed

Lin, Shi-Mei; Shi, Chao-Ming; Mu, Ming-Ming; Chen, Yong-Jun; Luo, Li

2018-07-01

An experimental trial was conducted to investigate the effects of high dietary starch levels on growth, hepatic glucose metabolism enzyme, antioxidant capacity and immune responses of largemouth bass, Micropterus salmoides. Fish (initial body weight: 16.9 ± 0.24 g) were fed three isonitrogenous and isoenergetic semi-purified diets containing 5%, 10% and 20% wheat starch, respectively. The results indicated that fish fed 5% and 10% starch diets showed significantly better weight gain, specific growth rate (SGR), protein efficiency ratio (PER) and feed conversion ratio (FCR) compared with that fed 20% starch diet. Meanwhile, fish fed 20% starch diet had a significantly higher hepatic glycogen and muscle glycogen contents than those fed the other diets. The alanine amiotransferase (ALT) and aspartate transaminase (AST) activities, glucose and insulin contents in plasma increased significantly with dietary starch levels, whereas triglyceride content showed the opposite trend. In addition, the highest glucokinase (GK), pyruvate kinase (PK) and phosphofructokinase (PFK) activities in liver were also observed in fish fed 20% starch diet. However, both fructose-1,6-bisphosphatase (FBPase) and pyruvate carboxylase (PC) activities in liver decreased significantly as dietary starch levels increased. Moreover, the lower superoxide dismutase (SOD) and catalase (CAT), the higher malondialdehyde (MDA) contents in liver were observed in fish fed 20% starch diets. Compared to the 5% and 10% starch, the 20% starch could enhance the content of plasma nitric oxide (NO) and the activities of inducible nitric oxide synthase (iNOS) and alkaline phosphatase (ALP). Results demonstrate that the starch levels may affect growth performance and metabolic changes, which suggest that high-starch diets were inefficiently used as an energy source by M. salmoides juveniles. Excessive dietary starch contents could result in oxidative stress, suppress innate immunity, and thus affect the health status of M. salmoides. Copyright © 2018. Published by Elsevier Ltd.

Dietary starch intake modifies the relation between copy number variation in the salivary amylase gene and BMI.

PubMed

Rukh, Gull; Ericson, Ulrika; Andersson-Assarsson, Johanna; Orho-Melander, Marju; Sonestedt, Emily

2017-07-01

Background: Studies have shown conflicting associations between the salivary amylase gene ( AMY1 ) copy number and obesity. Salivary amylase initiates starch digestion in the oral cavity; starch is a major source of energy in the diet. Objective: We investigated the association between AMY1 copy number and obesity traits, and the effect of the interaction between AMY1 copy number and starch intake on these obesity traits. Design: We first assessed the association between AMY1 copy number (genotyped by digital droplet polymerase chain reaction) and obesity traits in 4800 individuals without diabetes (mean age: 57 y; 60% female) from the Malmö Diet and Cancer Cohort. Then we analyzed interactions between AMY1 copy number and energy-adjusted starch intake (obtained by a modified diet history method) on body mass index (BMI) and body fat percentage. Results: AMY1 copy number was not associated with BMI ( P = 0.80) or body fat percentage ( P = 0.38). We observed a significant effect of the interaction between AMY1 copy number and starch intake on BMI ( P -interaction = 0.007) and body fat percentage ( P -interaction = 0.03). Upon stratification by dietary starch intake, BMI tended to decrease with increasing AMY1 copy numbers in the low-starch intake group ( P = 0.07) and tended to increase with increasing AMY1 copy numbers in the high-starch intake group ( P = 0.08). The lowest mean BMI was observed in the group of participants with a low AMY1 copy number and a high dietary intake of starch. Conclusions: Our findings suggest an effect of the interaction between starch intake and AMY1 copy number on obesity. Individuals with high starch intake but low genetic capacity to digest starch had the lowest BMI, potentially because larger amounts of undigested starch are transported through the gastrointestinal tract, contributing to fewer calories extracted from ingested starch. © 2017 American Society for Nutrition.

PROTEIN TARGETING TO STARCH Is Required for Localising GRANULE-BOUND STARCH SYNTHASE to Starch Granules and for Normal Amylose Synthesis in Arabidopsis

PubMed Central

Seung, David; Soyk, Sebastian; Coiro, Mario; Maier, Benjamin A.; Eicke, Simona; Zeeman, Samuel C.

2015-01-01

The domestication of starch crops underpinned the development of human civilisation, yet we still do not fully understand how plants make starch. Starch is composed of glucose polymers that are branched (amylopectin) or linear (amylose). The amount of amylose strongly influences the physico-chemical behaviour of starchy foods during cooking and of starch mixtures in non-food manufacturing processes. The GRANULE-BOUND STARCH SYNTHASE (GBSS) is the glucosyltransferase specifically responsible for elongating amylose polymers and was the only protein known to be required for its biosynthesis. Here, we demonstrate that PROTEIN TARGETING TO STARCH (PTST) is also specifically required for amylose synthesis in Arabidopsis. PTST is a plastidial protein possessing an N-terminal coiled coil domain and a C-terminal carbohydrate binding module (CBM). We discovered that Arabidopsis ptst mutants synthesise amylose-free starch and are phenotypically similar to mutants lacking GBSS. Analysis of granule-bound proteins showed a dramatic reduction of GBSS protein in ptst mutant starch granules. Pull-down assays with recombinant proteins in vitro, as well as immunoprecipitation assays in planta, revealed that GBSS physically interacts with PTST via a coiled coil. Furthermore, we show that the CBM domain of PTST, which mediates its interaction with starch granules, is also required for correct GBSS localisation. Fluorescently tagged Arabidopsis GBSS, expressed either in tobacco or Arabidopsis leaves, required the presence of Arabidopsis PTST to localise to starch granules. Mutation of the CBM of PTST caused GBSS to remain in the plastid stroma. PTST fulfils a previously unknown function in targeting GBSS to starch. This sheds new light on the importance of targeting biosynthetic enzymes to sub-cellular sites where their action is required. Importantly, PTST represents a promising new gene target for the biotechnological modification of starch composition, as it is exclusively involved in amylose synthesis. PMID:25710501

Fusion proteins comprising the catalytic domain of mutansucrase and a starch-binding domain can alter the morphology of amylose-free potato starch granules during biosynthesis.

PubMed

Nazarian Firouzabadi, Farhad; Kok-Jacon, Géraldine A; Vincken, Jean-Paul; Ji, Qin; Suurs, Luc C J M; Visser, Richard G F

2007-10-01

It has been shown previously that mutan can be co-synthesized with starch when a truncated mutansucrase (GtfICAT) is directed to potato tuber amyloplasts. The mutan seemed to adhere to the isolated starch granules, but it was not incorporated in the starch granules. In this study, GtfICAT was fused to the N- or C-terminus of a starch-binding domain (SBD). These constructs were introduced into two genetically different potato backgrounds (cv. Kardal and amf), in order to bring GtfICAT in more intimate contact with growing starch granules, and to facilitate the incorporation of mutan polymers in starch. Fusion proteins of the appropriate size were evidenced in starch granules, particularly in the amf background. The starches from the various GtfICAT/SBD transformants seemed to contain less mutan than those from transformants with GtfICAT alone, suggesting that the appended SBD might inhibit the activity of GtfICAT in the engineered fusion proteins. Scanning electron microscopy showed that expression of SBD-GtfICAT resulted in alterations of granule morphology in both genetic backgrounds. Surprisingly, the amf starches containing SBD-GtfICAT had a spongeous appearance, i.e., the granule surface contained many small holes and grooves, suggesting that this fusion protein can interfere with the lateral interactions of amylopectin sidechains. No differences in physico-chemical properties of the transgenic starches were observed. Our results show that expression of granule-bound and "soluble" GtfICAT can affect starch biosynthesis differently.

Degradation of Glucan Primers in the Absence of Starch Synthase 4 Disrupts Starch Granule Initiation in Arabidopsis*

PubMed Central

Lu, Kuan-Jen; Stettler, Michaela; Streb, Sebastian

2016-01-01

Arabidopsis leaf chloroplasts typically contain five to seven semicrystalline starch granules. It is not understood how the synthesis of each granule is initiated or how starch granule number is determined within each chloroplast. An Arabidopsis mutant lacking the glucosyl-transferase, STARCH SYNTHASE 4 (SS4) is impaired in its ability to initiate starch granules; its chloroplasts rarely contain more than one large granule, and the plants have a pale appearance and reduced growth. Here we report that the chloroplastic α-amylase AMY3, a starch-degrading enzyme, interferes with granule initiation in the ss4 mutant background. The amy3 single mutant is similar in phenotype to the wild type under normal growth conditions, with comparable numbers of starch granules per chloroplast. Interestingly, the ss4 mutant displays a pleiotropic reduction in the activity of AMY3. Remarkably, complete abolition of AMY3 (in the amy3 ss4 double mutant) increases the number of starch granules produced in each chloroplast, suppresses the pale phenotype of ss4, and nearly restores normal growth. The amy3 mutation also restores starch synthesis in the ss3 ss4 double mutant, which lacks STARCH SYNTHASE 3 (SS3) in addition to SS4. The ss3 ss4 line is unable to initiate any starch granules and is thus starchless. We suggest that SS4 plays a key role in granule initiation, allowing it to proceed in a way that avoids premature degradation of primers by starch hydrolases, such as AMY3. PMID:27458017

A Study of Moisture Sorption and Dielectric Processes of Starch and Sodium Starch Glycolate : Theme: Formulation and Manufacturing of Solid Dosage Forms Guest Editors: Tony Zhou and Tonglei Li.

PubMed

Hiew, Tze Ning; Huang, Rongying; Popov, Ivan; Feldman, Yuri; Heng, Paul Wan Sia

2017-12-01

This study explored the potential of combining the use of moisture sorption isotherms and dielectric relaxation profiles of starch and sodium starch glycolate (SSG) to probe the location of moisture in dried and hydrated samples. Starch and SSG samples, dried and hydrated, were prepared. For hydrated samples, their moisture contents were determined. The samples were probed by dielectric spectroscopy using a frequency band of 0.1 Hz to 1 MHz to investigate their moisture-related relaxation profiles. The moisture sorption and desorption isotherms of starch and SSG were generated using a vapor sorption analyzer, and modeled using the Guggenheim-Anderson-de Boer equation. A clear high frequency relaxation process was detected in both dried and hydrated starches, while for dried starch, an additional slower low frequency process was also detected. The high frequency relaxation processes in hydrated and dried starches were assigned to the coupled starch-hydrated water relaxation. The low frequency relaxation in dried starch was attributed to the local chain motions of the starch backbone. No relaxation process associated with water was detected in both hydrated and dried SSG within the frequency and temperature range used in this study. The moisture sorption isotherms of SSG suggest the presence of high energy free water, which could have masked the relaxation process of the bound water during dielectric measurements. The combined study of moisture sorption isotherms and dielectric spectroscopy was shown to be beneficial and complementary in probing the effects of moisture on the relaxation processes of starch and SSG.

Suppression of starch synthase I expression affects the granule morphology and granule size and fine structure of starch in wheat endosperm

PubMed Central

2014-01-01

Studies in Arabidopsis and rice suggest that manipulation of starch synthase I (SSI) expression in wheat may lead to the production of wheat grains with novel starch structure and properties. This work describes the suppression of SSI expression in wheat grains using RNAi technology, which leads to a low level of enzymatic activity for SSI in the developing endosperm, and a low abundance of SSI protein inside the starch granules of mature grains. The amylopectin fraction of starch from the SSI suppressed lines showed an increased frequency of very short chains (degree of polymerization, dp 6 and 7), a lower proportion of short chains (dp 8–12), and more intermediate chains (dp 13–20) than in the grain from their negative segregant lines. In the most severely affected line, amylose content was significantly increased, the morphology of starch granules was changed, and the proportion of B starch granules was significantly reduced. The change of the fine structure of the starch in the SSI-RNAi suppression lines alters the gelatinization temperature, swelling power, and viscosity of the starch. This work demonstrates that the roles of SSI in the determination of starch structure and properties are similar among different cereals and Arabidopsis. PMID:24634486

The potential of resistant starch as a prebiotic.

PubMed

Zaman, Siti A; Sarbini, Shahrul R

2016-01-01

Resistant starch is defined as the total amount of starch and the products of starch degradation that resists digestion in the small intestine. Starches that were able to resist the digestion will arrive at the colon where they will be fermented by the gut microbiota, producing a variety of products which include short chain fatty acids that can provide a range of physiological benefits. There are several factors that could affect the resistant starch content of a carbohydrate which includes the starch granule morphology, the amylose-amylopectin ratio and its association with other food component. One of the current interests on resistant starch is their potential to be used as a prebiotic, which is a non-digestible food ingredient that benefits the host by stimulating the growth or activity of one or a limited number of beneficial bacteria in the colon. A resistant starch must fulfill three criterions to be classified as a prebiotic; resistance to the upper gastrointestinal environment, fermentation by the intestinal microbiota and selective stimulation of the growth and/or activity of the beneficial bacteria. The market of prebiotic is expected to reach USD 198 million in 2014 led by the export of oligosaccharides. Realizing this, novel carbohydrates such as resistant starch from various starch sources can contribute to the advancement of the prebiotic industry.

Effect of heat-moisture treatment on the structural, physicochemical, and rheological characteristics of arrowroot starch.

PubMed

Pepe, Larissa S; Moraes, Jaqueline; Albano, Kivia M; Telis, Vânia R N; Franco, Célia M L

2016-04-01

The effect of heat-moisture treatment on structural, physicochemical, and rheological characteristics of arrowroot starch was investigated. Heat-moisture treatment was performed with starch samples conditioned to 28% moisture at 100 ℃ for 2, 4, 8, and 16 h. Structural and physicochemical characterization of native and modified starches, as well as rheological assays with gels of native and 4 h modified starches subjected to acid and sterilization stresses were performed. Arrowroot starch had 23.1% of amylose and a CA-type crystalline pattern that changed over the treatment time to A-type. Modified starches had higher pasting temperature and lower peak viscosity while breakdown viscosity practically disappeared, independently of the treatment time. Gelatinization temperature and crystallinity increased, while enthalpy, swelling power, and solubility decreased with the treatment. Gels from modified starches, independently of the stress conditions, were found to have more stable apparent viscosities and higher G' and G″ than gels from native starch. Heat-moisture treatment caused a reorganization of starch chains that increased molecular interactions. This increase resulted in higher paste stability and strengthened gels that showed higher resistance to shearing and heat, even after acid or sterilization conditions. A treatment time of 4 h was enough to deeply changing the physicochemical properties of starch. © The Author(s) 2015.

Evaluation of the Disintegrant Properties of Native Starches of Five New Cassava Varieties in Paracetamol Tablet Formulations

PubMed Central

Adjei, Frank Kumah; Osei, Yaa Asantewaa; Kuntworbe, Noble

2017-01-01

The disintegrant potential of native starches of five new cassava (Manihot esculenta Crantz.) varieties developed by the Crops Research Institute of Ghana (CRIG) was studied in paracetamol tablet formulations. The yield of the starches ranged from 8.0 to 26.7%. The starches were basic (pH: 8.1–9.9), with satisfactory moisture content (≤15%), swelling capacity (≥20%), ash values (<1%), flow properties, and negligible toxic metal ion content, and compatible with the drug. The tensile strength (Ts), crushing strength (Cs), and friability (Ft) of tablets containing 5–10% w/w of the cassava starches were similar (p > 0.05) to those containing maize starch BP. The disintegration times of the tablets decreased with increase in concentration of the cassava starches. The tablets passed the disintegration test (DT ≤ 15 min) and exhibited faster disintegration times (p > 0.05) than those containing maize starch BP. The disintegration efficiency ratio (DER) and the disintegration parameter DERc of the tablets showed that cassava starches V20, V40, and V50 had better disintegrant activity than maize starch BP. The tablets passed the dissolution test for immediate release tablets (≥70% release in 45 min) with dissolution rates similar to those containing maize starch BP. PMID:28781909

Structure, morphology and functionality of acetylated and oxidised barley starches.

PubMed

El Halal, Shanise Lisie Mello; Colussi, Rosana; Pinto, Vânia Zanella; Bartz, Josiane; Radunz, Marjana; Carreño, Neftali Lenin Villarreal; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2015-02-01

Acetylation and oxidation are chemical modifications which alter the properties of starch. The degree of modification of acetylated and oxidized starches is dependent on the catalyst and active chlorine concentrations, respectively. The objective of this study was to evaluate the effect of acetylation and oxidation on the structural, morphological, physical-chemical, thermal and pasting properties of barley starch. Barley starches were acetylated at different catalyst levels (11%, 17%, and 23% of NaOH solution) and oxidized at different sodium hypochlorite concentrations (1.0%, 1.5%, and 2.0% of active chlorine). Fourier-transformed infrared spectroscopy (FTIR), X-ray diffractograms, thermal, morphological, and pasting properties, swelling power and solubility of starches were evaluated. The degree of substitution (DS) of the acetylated starches increased with the rise in catalyst concentration. The percentage of carbonyl (CO) and carboxyl (COOH) groups in oxidized starches also increased with the rise of active chlorine level. The presence of hydrophobic acetyl groups, carbonyl and carboxyl groups caused a partial disorganization and depolymerization of starch granules. The structural, morphological and functional changes in acetylated and oxidized starches varied according to reaction conditions. Acetylation makes barley starch more hydrophobic by the insertion of acetyl groups. Also the oxidation promotes low retrogradation and viscosity. All these characteristics are important for biodegradable film production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Starch Biosynthesis in Guard Cells But Not in Mesophyll Cells Is Involved in CO2-Induced Stomatal Closing1[OPEN

PubMed Central

Stephan, Aaron B.; Schroeder, Julian I.

2016-01-01

Starch metabolism is involved in stomatal movement regulation. However, it remains unknown whether starch-deficient mutants affect CO2-induced stomatal closing and whether starch biosynthesis in guard cells and/or mesophyll cells is rate limiting for high CO2-induced stomatal closing. Stomatal responses to [CO2] shifts and CO2 assimilation rates were compared in Arabidopsis (Arabidopsis thaliana) mutants that were either starch deficient in all plant tissues (ADP-Glc-pyrophosphorylase [ADGase]) or retain starch accumulation in guard cells but are starch deficient in mesophyll cells (plastidial phosphoglucose isomerase [pPGI]). ADGase mutants exhibited impaired CO2-induced stomatal closure, but pPGI mutants did not, showing that starch biosynthesis in guard cells but not mesophyll functions in CO2-induced stomatal closing. Nevertheless, starch-deficient ADGase mutant alleles exhibited partial CO2 responses, pointing toward a starch biosynthesis-independent component of the response that is likely mediated by anion channels. Furthermore, whole-leaf CO2 assimilation rates of both ADGase and pPGI mutants were lower upon shifts to high [CO2], but only ADGase mutants caused impairments in CO2-induced stomatal closing. These genetic analyses determine the roles of starch biosynthesis for high CO2-induced stomatal closing. PMID:27208296

Production and characterization of cellulose reinforced starch (CRT) films.

PubMed

Sudharsan, K; Chandra Mohan, C; Azhagu Saravana Babu, P; Archana, G; Sabina, K; Sivarajan, M; Sukumar, M

2016-02-01

Starch from Tamarind seed is considered to be a nonedible and inexpensive component, with many industrial applications. Extraction and characterization of tamarind seed starch was carried out for the synthesis of biopolymer. Tamarind seeds were collected, cleaned and further roasted, decorticated, and pulverized to get starch powder. Total starch content present in each tamarind seed is estimated to be around 65-70%. About 84.68% purified starch can be recovered from the tamarind seed. Defatted Tamarind seed starch has an amylose content of 27.55 wt.% and 72.45 wt.% of amylopectin. Morphological (SEM) and X-ray diffraction were used to evaluate crystallinity. Likewise, TGA and DSC of starch have also been analyzed. Thermal properties of starch obtained from tamarind seeds showed good thermal stability when compared to other starch sources such as Mesquite seed and Mango kernel. This study proved that the tamarind seed starch can be used as a potential biopolymer material. Thermo-stable biofilms were produced through initial optimization studies. Predictive response surface quadratic models were constructed for prediction and optimization of biofilm mechanical properties. Correlation coefficient values were calculated to me more than 0.90 for mechanical responses which implies the fitness of constructed model with experimental data. Copyright © 2015 Elsevier B.V. All rights reserved.

Starch Characteristics Linked to Gluten-Free Products

PubMed Central

Horstmann, Stefan W.; Lynch, Kieran M.; Arendt, Elke K.

2017-01-01

The increasing prevalence of coeliac disease (CD) and gluten-related disorders has led to increasing consumer demand for gluten-free products with quality characteristics similar to wheat bread. The replacement of gluten in cereal-based products remains a challenge for scientists, due to its unique role in network formation, which entraps air bubbles. When gluten is removed from a flour, starch is the main component left. Starch is used as gelling, thickening, adhesion, moisture-retention, stabilizing, film forming, texturizing and anti-staling ingredient. The extent of these properties varies depending on the starch source. The starches can additionally be modified increasing or decreasing certain properties of the starch, depending on the application. Starch plays an important role in the formulation of bakery products and has an even more important role in gluten-free products. In gluten-free products, starch is incorporated into the food formulation to improve baking characteristics such as the specific volume, colour and crumb structure and texture. This review covers a number of topics relating to starch; including; an overview of common and lesser researched starches; chemical composition; morphology; digestibility; functionality and methods of modification. The emphasis of this review is on starch and its properties with respect to the quality of gluten-free products. PMID:28383504

Protein and starch concentrates of air-classified field pea and zero-tannin faba bean for weaned pigs.

PubMed

Gunawardena, C K; Zijlstra, R T; Goonewardene, L A; Beltranena, E

2010-08-01

Air-classified pulse (non-oilseed legume) protein and starch may replace specialty protein and starch feedstuffs in diets for weaned pigs. In Exp. 1, three specialty protein sources (5% soy protein concentrate, 5% corn gluten meal, and 5% menhaden meal in the control diet) were replaced with 16% zero-tannin hulled or dehulled faba bean, or 17.5% field pea protein concentrate. In total, 192 group-housed pigs (2 gilts and 2 barrows per pen; BW = 7.5 +/- 1.4 kg) were fed wheat-based diets (3.60 Mcal/kg of DE and 3.3 g of standardized ileal digestible Lys/Mcal DE) over 28 d for 12 pen observations per each of 4 diets. Overall, protein source did not affect ADFI, ADG, or G:F. Apparent total tract digestibility (ATTD) of DM, GE, and P was greater (P < 0.05) for dehulled faba bean and field pea protein concentrate diets than the diet with 3 specialty protein sources. In Exp. 2, faba bean and field pea starch concentrates were compared with corn, wheat, tapioca, and potato starch as dietary energy sources. In total, 36 individually housed barrows (BW = 8.0 +/- 1.5 kg) were fed 1 of 6 diets for 15 d. Feces and urine were collected from d 8 to 14, and jugular blood was sampled after overnight fast and refeeding on d 15. Starch source did not affect N retention as a percentage of N intake. For d 0 to 14, ADFI of pigs fed field pea starch was greater (P < 0.05) than pigs fed corn, wheat, potato, and faba bean starch. Pigs fed tapioca, field pea, wheat, or corn starch grew faster (P < 0.05) than those fed faba bean or potato starch. For d 0 to 14, pigs fed corn or wheat starch had a 0.1 greater (P < 0.05) G:F than pigs fed faba bean, field pea, or potato starch. The ATTD of DM, GE, CP, and starch and the DE value of potato starch were much less (P < 0.05) than those of other starch diets. Postprandial plasma glucose was 4.9, 6.3, and 9 mmol/L greater (P < 0.05) for pigs fed tapioca than for pigs fed faba bean, wheat, and potato starch, respectively. However, postprandial plasma insulin tended to be 844 and 577 pmol/L greater (P < 0.10) for pigs fed faba bean and corn starch, respectively, than for pigs fed potato starch. The high insulin response of pigs fed faba starch could not be explained. In conclusion, air-classified pulse protein concentrates can replace specialty protein feedstuffs in diets for weaned pigs. Feeding air-classified pulse starch concentrates to starter pigs achieved a similar N retention as a percentage of N intake. The factors responsible for the reduced ADFI associated with feeding faba bean starch remain unclear.

Morphological and mechanical characterization of thermoplastic starch and its blends with polylactic acid using cassava starch and bagasse

USDA-ARS?s Scientific Manuscript database

This study aims the use of an agro waste coming from the industrialization of cassava starch, known as cassava bagasse (BG). This material contains residual starch and cellulose fibers which can be used to obtain thermoplastic starch (TPS) and /or blends reinforced with fibers. In this context, it w...

Physicochemical properties of maca starch.

PubMed

Zhang, Ling; Li, Guantian; Wang, Sunan; Yao, Weirong; Zhu, Fan

2017-03-01

Maca (Lepidium meyenii Walpers) is gaining research attention due to its unique bioactive properties. Starch is a major component of maca roots, thus representing a novel starch source. In this study, the properties of three maca starches (yellow, purple and black) were compared with commercially maize, cassava, and potato starches. The starch granule sizes ranged from 9.0 to 9.6μm, and the granules were irregularly oval. All the maca starches presented B-type X-ray diffraction patterns, with the relative degree of crystallinity ranging from 22.2 to 24.3%. The apparent amylose contents ranged from 21.0 to 21.3%. The onset gelatinization temperatures ranged from 47.1 to 47.5°C as indicated by differential scanning calorimetry. Significant differences were observed in the pasting properties and textural parameters among all of the studied starches. These characteristics suggest the utility of native maca starch in products subjected to low temperatures during food processing and other industrial applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analysis of Resistant Starches in Rat Cecal Contents Using Fourier Transform Infrared Photoacoustic Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Timothy J.; Ai, Yongfeng; Jones, Roger W.

Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) qualitatively and quantitatively measured resistant starch (RS) in rat cecal contents. Fisher 344 rats were fed diets of 55% (w/w, dry basis) starch for 8 weeks. Cecal contents were collected from sacrificed rats. A corn starch control was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. To calibrate the FTIR-PAS analysis, samples from each diet were analyzed using an enzymatic assay. A partial least-squares cross-validation plot generated from the enzymatic assay and FTIR-PAS spectral results for starch fitmore » the ideal curve with a R2 of 0.997. A principal component analysis plot of components 1 and 2 showed that spectra from diets clustered significantly from each other. This study clearly showed that FTIR-PAS can accurately quantify starch content and identify the form of starch in complex matrices.« less

Acetylated adipate of retrograded starch as RS 3/4 type resistant starch.

PubMed

Kapelko-Żeberska, M; Zięba, T; Spychaj, R; Gryszkin, A

2015-12-01

This study was aimed at producing acetylated adipate of retrograded starch (ADA-R) with various degrees of substitution with functional groups and at determining the effect of esterification degree on resistance and pasting characteristics of the produced preparations. Paste was prepared from native potato starch, and afterwards frozen and defrosted. After drying and disintegration, the paste was acetylated and crosslinked using various doses of reagents. An increase in the total degree of esterification of the produced ADA-R-preparation caused an increase in its resistance to the action of amyloglucosidase. Viscosity of the paste produced from ADA-R-preparation in a wide range of acetylation degrees was increasing along with increasing crosslinking of starch. The study demonstrated that acetylated adipate of retrograded starch may be classified as a preparation of RS 3/4 type resistant starch (retrograded starch/chemically-modified starch) with good texture-forming properties. The conducted modification offers the possibility of modeling the level of resistance of the produced preparation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of formulae for estimating amylose content, amylopectin chain length distribution, and resistant starch content based on the iodine absorption curve of rice starch.

PubMed

Nakamura, Sumiko; Satoh, Hikaru; Ohtsubo, Ken'ichi

2015-01-01

Not only amylose but also amylopectin greatly affects the gelatinization properties of rice starch and the quality of cooked rice grains. We here characterized the starches of 32 rice cultivars and evaluated the relationship between their iodine absorption curve, apparent amylose content (AAC), pasting property, resistant starch (RS) content, and chain length distribution of amylopectin. We found that the iodine absorption curve differed among the various sample rice cultivars. Using the wavelength at which absorbance becomes maximum on iodine staining of starch (λmax), we propose a novel index, "new λmax" (AAC/(λmax of sample rice starches-λmax of glutinous rice starch)). We developed the novel estimation formulae for AAC, RS contents, and amylopectin fractions with the use of λmax and "new λmax." These formulae would lead to the improved method for estimating starch properties using an easy and rapid iodine colorimetric method.

Cooking behavior and starch digestibility of NUTRIOSE® (resistant starch) enriched noodles from sweet potato flour and starch.

PubMed

Menon, Renjusha; Padmaja, G; Sajeev, M S

2015-09-01

The effect of a resistant starch source, NUTRIOSE® FB06 at 10%, 15% and 20% in sweet potato flour (SPF) and 5% and 10% in sweet potato starch (SPS) in reducing the starch digestibility and glycaemic index of noodles was investigated. While NUTRIOSE (10%) significantly reduced the cooking loss in SPF noodles, this was enhanced in SPS noodles and guar gum (GG) supplementation reduced CL of both noodles. In vitro starch digestibility (IVSD) was significantly reduced in test noodles compared to 73.6g glucose/100g starch in control SPF and 65.9 g in SPS noodles. Resistant starch (RS) was 54.96% for NUTRIOSE (15%)+GG (1%) fortified SPF noodles and 53.3% for NUTRIOSE (5%)+GG (0.5%) fortified SPS noodles, as against 33.8% and 40.68%, respectively in SPF and SPS controls. Lowest glycaemic index (54.58) and the highest sensory scores (4.23) were obtained for noodles with 15% NUTRIOSE+1% GG. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of pullulan on the water distribution, microstructure and textural properties of rice starch gels during cold storage.

PubMed

Chen, Long; Tian, Yaoqi; Tong, Qunyi; Zhang, Zipei; Jin, Zhengyu

2017-01-01

The effects of pullulan on the water distribution, microstructure and textural properties of rice starch gels during cold storage were investigated by low field-nuclear magnetic resonance (LF-NMR), scanning electron microscope (SEM), and texture profile analysis (TPA). The addition of pullulan reduced the transversal relaxation time of rice starch gels during cold storage. The microstructure of rice starch gel with 0.5% pullulan was denser and more uniform compared with that of rice starch without pullulan in each period of storage time. With regard to textural properties, 0.01% pullulan addition did not significantly change the texture of rice starch gels, while 0.5% pullulan addition appeared to reduce the hardness and retain the springiness of rice starch gels (P⩽0.05). The restriction effects of pullulan on water mobility and starch retrogradation were hypothesized to be mainly responsible for the water retention, gel structure maintenance, and modification of the textural attributes of rice starch gels. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of magnetic starch on the clarification of hematite tailings wastewater

NASA Astrophysics Data System (ADS)

Yue, Tao; Wu, Xiqing

2018-02-01

The magnetic starch solution, synthesized by mixing the caustic starch, the Fe2+ solution (in some cases containing the Zn2+, Cu2+, Mn2+ or Mg2+ ions) and H2O2 solution, was used as the flocculant to investigate its clarification effect on hematite tailings wastewater. Based on the clarification tests and adsorption analysis it was demonstrated that the magnetic starch produced better clarification effect than the caustic starch, and the adsorption of magnetic starch onto hematite tailings particles was also stronger than the caustic starch. AFM found that the magnetic interaction between magnetic seeds and hematite is characteristic of long range force and greatly strengthens the adsorption of magnetic seeds onto fine hematite for agglomeration. FTIR indicates the starch adsorbed onto the surfaces of hematite and magnetic seeds, thus acting as the bridging between hematite particles and magnetic seeds, resulting in an intensified coverage of the starch onto hematite and positive action in the clarification.

The effect of high hydrostatic pressure treatment on the molecular structure of starches with different amylose content.

PubMed

Szwengiel, Artur; Lewandowicz, Grażyna; Górecki, Adrian R; Błaszczak, Wioletta

2018-02-01

The effect of high hydrostatic pressure processing (650MPa/9min) on molecular mass distribution, and hydrodynamic and structural parameters of amylose (maize, sorghum, Hylon VII) and amylopectin (waxy maize, amaranth) starches was studied. The starches were characterized by high-performance size-exclusion chromatography (HPSEC) equipped with static light scattering and refractive index detectors and by Fourier Transform Infrared (FTIR) spectroscopy. Significant changes were observed in molecular mass distribution of pressurized waxy maize starch. Changes in branches/branch frequency, intrinsic viscosity, and radius of gyration were observed for all treated starches. The combination of SEC and FTIR data showed that α-1,6-glycosidic bonds are more frequently split in pressurized amaranth, Hylon VII, and waxy maize starch, while in sorghum and maize starches, the α-1,4 bonds are most commonly split. Our results show that the structural changes found for pressurized starches were more strongly determined by the starch origin than by the processing applied. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development and characterisation of composite films made of kefiran and starch.

PubMed

Motedayen, Ali Akbar; Khodaiyan, Faramarz; Salehi, Esmail Atai

2013-02-15

In this study, new edible composite films were prepared by blending kefiran with corn starch. Film-forming solutions of different ratios of kefiran to corn starch (100/0, 70/30, 50/50, 30/70) were cast at room temperature. The effects of starch addition on the resulting films' physical, mechanical and water-vapor permeability (WVP) properties were investigated. Increasing starch content from 0% to 50% (v/v) decreased the WVP of films; however, with further starch addition the WVP increased. Also, this increase in starch content increased the tensile strength and extensibility of the composite films. However, these mechanical properties decreased at higher starch contents. Dynamic mechanical thermal analysis (DMTA) curves showed that addition of starch at all levels increased the glass transition temperature of films. The electron scanning micrograph for the composite film was homogeneous, without signs of phase separation between the components. Thus, it was observed that these two film-forming components were compatible, and that an interaction existed between them. Copyright © 2012 Elsevier Ltd. All rights reserved.

Structural basis for the slow digestion property of native cereal starches.

PubMed

Zhang, Genyi; Venkatachalam, Mahesh; Hamaker, Bruce R

2006-11-01

Native cereal starches are ideal slowly digestible starches (SDS), and the structural basis for their slow digestion property was investigated. The shape, size, surface pores and channels, and degree of crystallinity of starch granules were not related to the proportion of SDS, while semicrystalline structure was critical to the slow digestion property as evidenced by loss of SDS after cooking. The high proportion of SDS in cereal starches, as compared to potato starch, was related to their A-type crystalline structure with a lower degree of perfection as indicated by a higher amount of shortest A chains with a degree of polymerization (DP) of 5-10. The A-type amorphous lamellae, an important component of crystalline regions of native cereal starches, also affect the amount of SDS as shown by a reduction of SDS in lintnerized maize starches. These observations demonstrate that the supramolecular A-type crystalline structure, including the distribution and perfection of crystalline regions (both crystalline and amorphous lamellae), determines the slow digestion property of native cereal starches.

Autophagy Contributes to Leaf Starch Degradation[C][W

PubMed Central

Wang, Yan; Yu, Bingjie; Zhao, Jinping; Guo, Jiangbo; Li, Ying; Han, Shaojie; Huang, Lei; Du, Yumei; Hong, Yiguo; Tang, Dingzhong; Liu, Yule

2013-01-01

Transitory starch, a major photosynthetic product in the leaves of land plants, accumulates in chloroplasts during the day and is hydrolyzed to maltose and Glc at night to support respiration and metabolism. Previous studies in Arabidopsis thaliana indicated that the degradation of transitory starch only occurs in the chloroplasts. Here, we report that autophagy, a nonplastidial process, participates in leaf starch degradation. Excessive starch accumulation was observed in Nicotiana benthamiana seedlings treated with an autophagy inhibitor and in autophagy-related (ATG) gene-silenced N. benthamiana and in Arabidopsis atg mutants. Autophagic activity in the leaves responded to the dynamic starch contents during the night. Microscopy showed that a type of small starch granule-like structure (SSGL) was localized outside the chloroplast and was sequestered by autophagic bodies. Moreover, an increased number of SSGLs was observed during starch depletion, and disruption of autophagy reduced the number of vacuole-localized SSGLs. These data suggest that autophagy contributes to transitory starch degradation by sequestering SSGLs to the vacuole for their subsequent breakdown. PMID:23564204

Infrared spectroscopy as a tool to characterise starch ordered structure--a joint FTIR-ATR, NMR, XRD and DSC study.

PubMed

Warren, Frederick J; Gidley, Michael J; Flanagan, Bernadine M

2016-03-30

Starch has a heterogeneous, semi-crystalline granular structure and the degree of ordered structure can affect its behaviour in foods and bioplastics. A range of methodologies are employed to study starch structure; differential scanning calorimetry, (13)C nuclear magnetic resonance, X-ray diffraction and Fourier transform infrared spectroscopy (FTIR). Despite the appeal of FTIR as a rapid, non-destructive methodology, there is currently no systematically defined quantitative relationship between FTIR spectral features and other starch structural measures. Here, we subject 61 starch samples to structural analysis, and systematically correlate FTIR spectra with other measures of starch structure. A hydration dependent peak position shift in the FTIR spectra of starch is observed, resulting from increased molecular order, but with complex, non-linear behaviour. We demonstrate that FTIR is a tool that can quantitatively probe short range interactions in starch structure. However, the assumptions of linear relationships between starch ordered structure and peak ratios are overly simplistic. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vitro digestion and physicochemical characteristics of corn starch mixed with amino acid modified by low pressure treatment.

PubMed

Ji, Ying

2018-03-01

The digestibility and molecular structure of corn starch mixed with amino acid modified by low-pressure treatment (LPT) was investigated. Amino acid induced a significant increase in the slowly digestible starch (SDS) and decrease in the rapidly digestible starch (RDS) after LPT. The reason is the formation of ester bond between the molecular chains of amino acid and starch. Low pressure treatment altered greatly the morphology of corn starch mixed with or without amino acid. After LPT, less ordered Maltese and more granule fragments were observed for starch-amino acid complex. An increase in size distribution was obvious after LPT and the size distribution curves provided from a new variety. We found that higher enthalpy and relative crystallinity of the starch-amino acid complex were associated with a higher SDS content. It can be inferred that LPT had a greater impact on the digestion and structural characterization of corn starch mixed with amino acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mechanical and thermal properties of promising polymer composites for food packaging applications

NASA Astrophysics Data System (ADS)

Abdellah Ali, S. F.

2016-07-01

Blending starches with biodegradable polycaprolactone (PCL) was used as a route to make processable thermoplastics. When developing biodegradable polymer composites it is important to use high concentrations of starch for legislative and cost reasons. The addition of starch has a significant effect on all physical properties including toughness, elongation at break and the rheological behaviour of the melt. To enhance the physical properties, we used cellulose acetate propionate (CAP) as a cellulose derivative with high amylase starch and PCL blends. It is suggested that the PCL/starch/CAP blends are partially miscible. It was found that the yield tensile strengths of most PCL/Starch/CAP blends were higher than that of pure PCL itself. There was a big difference between glass transition temperature values of PCL/Starch/CAP blends and the pure PCL glass transition temperature which indicates that no phase separation occurs. Addition of CAP to starch and PCL blends improved the mechanical and thermal properties even at high content of starch.

Morphological, Thermal, and Rheological Properties of Starches from Maize Mutants Deficient in Starch Synthase III.

PubMed

Zhu, Fan; Bertoft, Eric; Li, Guantian

2016-08-31

Morphological, thermal, and rheological properties of starches from maize mutants deficient in starch synthase III (SSIII) with a common genetic background (W64A) were studied and compared with the wild type. SSIII deficiency reduced granule size of the starches from 16.7 to ∼11 μm (volume-weighted mean). Thermal analysis showed that SSIII deficiency decreased the enthalpy change of starch during gelatinization. Steady shear analysis showed that SSIII deficiency decreased the consistency coefficient and yield stress during steady shearing, whereas additional deficiency in granule-bound starch synthase (GBSS) increased these values. Dynamic oscillatory analysis showed that SSIII deficiency decreased G' at 90 °C during heating and increased it when the paste was cooled to 25 °C at 40 Hz during a frequency sweep. Additional GBSS deficiency further decreased the G'. Structural and compositional bases responsible for these changes in physical properties of the starches are discussed. This study highlighted the relationship between SSIII and some physicochemical properties of maize starch.

Comparison of various types of starch when used in meat sausages.

PubMed

Skrede, G

1989-01-01

Technological and sensory properties of meat sausages formulated with 4·0% of either potato flour, modified (acetylated distarch phosphate) potato starch, wheat, corn or tapioca starch were compared. Sausages were analyzed after cooking at temperatures between 65 and 85°C followed by storage at 5°C and -25°C. Characteristics evaluated were weight loss during cooking and storage, instrumentally and sensory assessed firmness, taste and smell of sausages. The results revealed differences in the suitability of starches for use in meat sausages. Part of the differences could be ascribed to differences in gelatination properties of the starches. With the criteria used for evaluating quality, potato flour was rated as the best suited starch followed by wheat starch while tapioca was rated as the least suited. Corn starch required cooking temperatures above 75°C and showed relatively low freeze/thaw stability. The modified potato starch stored well both above and below the freezing point. Copyright © 1989. Published by Elsevier Ltd.

Thermal Properties of Starch From New Corn Lines as Impacted by Environment and During Line Development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lenihan, Elizabeth M

The objectives of this research were to further characterize exotic by adapted corn inbreds by studying the impact of environment on their starch thermal properties, and investigating the development of starch thermal properties during kernel maturation by using differential scanning calorimetry (DSC). A method to expedite identification of unusual starch thermal traits was investigated by examining five corn kernels at a time, instead of one kernel, which the previous screening methods used. Corn lines with known thermal functions were blended with background starch (control) in ratios of unique starch to control starch, and analyzed by using DSC. Control starch wasmore » representative of typical corn starch. The values for each ratio within a mutant type were unique (α < 0.01) for most DSC measurements. These results supported the five-kernel method for rapidly screening large amounts of corn germplasm to identify unusual starch traits. The effects of 5 growing locations on starch thermal properties from exotic by adapted corn and Corn Belt lines were studied using DSC. The warmest location, Missouri, generally produced starch with greater gelatinization onset temperature (T oG), narrower range of gelatinization (R G), and greater enthalpy of gelatinization (ΔH G). The coolest location, Illinois, generally resulted in starch with lower T oG, wider R G, and lower ΔH G. Starch from the Ames 1 farm had thermal properties similar to those of Illinois, whereas starch from the Ames 2 farm had thermal properties similar to those of Missouri. The temperature at Ames 2 may have been warmer since it was located near a river; however, soil type and quality also were different. Final corn starch structure and function change during development and maturity. Thus, the changes in starch thermal properties during 5 stages of endosperm development from exotic by adapted corn and Corn Belt lines at two locations were studied by using DSC. The T oG tended to decrease during maturation of the kernel, whereas theΔH G tended not to change. Retrogradation parameters did not vary greatly among days after pollination (DAP) and between locations. Genotypes were affected differently by environments and significant interactions were found between genotype, environment,and DAP.« less

Characterization and Prebiotic Effect of the Resistant Starch from Purple Sweet Potato.

PubMed

Zheng, Yafeng; Wang, Qi; Li, Baoyu; Lin, Liangmei; Tundis, Rosa; Loizzo, Monica R; Zheng, Baodong; Xiao, Jianbo

2016-07-19

Purple sweet potato starch is a potential resource for resistant starch production. The effects of heat-moisture treatment (HMT) and enzyme debranching combined heat-moisture treatment (EHMT) on the morphological, crystallinity and thermal properties of PSP starches were investigated. The results indicated that, after HMT or EHMT treatments, native starch granules with smooth surface was destroyed to form a more compact, irregular and sheet-like structure. The crystalline pattern was transformed from C-type to B-type with decreasing relative crystallinity. Due to stronger crystallites formed in modified starches, the swelling power and solubility of HMT and EHMT starch were decreased, while the transition temperatures and gelatinization enthalpy were significantly increased. In addition, HMT and EHMT exhibited greater effects on the proliferation of bifidobacteria compared with either glucose or high amylose maize starch.

Structure and physicochemical properties of starches in lotus (Nelumbo nucifera Gaertn.) rhizome

PubMed Central

Yu, Huaguang; Cheng, Libao; Yin, Jingjing; Yan, Shunjun; Liu, Kejun; Zhang, Fengmin; Xu, Bin; Li, Liangjun

2013-01-01

The type and content of starch are believed to be the most critical factors in determining the storage and processing quality of lotus rhizome species, and the intention of this study is to survey the structure and properties of starches isolated from rhizomes of two lotus cultivars using X-ray powder diffraction, solid-state nuclear magnetic resonance spectroscopy, attenuated total reflectance-Fourier transform infrared spectroscopy, scanning electron microscope, differential scanning calorimetry, and rapid viscosity analyzer (RVA). Starch in rhizome of cultivar Meirenhong exhibited C-type X-ray diffraction pattern, while starch in rhizome of cultivar Wawalian showed A-type pattern. 13C cross-polarization magic-angle spinning nuclear magnetic resonance (13C CP-MAS NMR) also confirmed the polymorphs. The relative crystallinity of two starches was quantitatively estimated from two methods and compared. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) results indicated that the external regions of the starch granules had a great level of ordered structure. Starch granules in Meirenhong showed oval-shaped granules, while starch granules in Wawalian were elongated and oval in shape with relatively large size. Gelatinization temperatures of starch in Meirenhong and Wawalian were 330.5 and 342.4 K, respectively, and the gelatinization temperature range of Meirenhong was significantly wider than that of Wawalian. Starch in rhizome of cultivar Meirenhong showed lower pasting temperature, lower hot and cool viscosities, lower setback, and higher peak viscosity and breakdown than those of Wawalian in RVA pasting profiles at 6% starch concentration. PMID:24804031

Using proteomic analysis to investigate uniconazole-induced phytohormone variation and starch accumulation in duckweed (Landoltia punctata).

PubMed

Huang, Mengjun; Fang, Yang; Liu, Yang; Jin, Yanling; Sun, Jiaolong; Tao, Xiang; Ma, Xinrong; He, Kaize; Zhao, Hai

2015-09-15

Duckweed (Landoltia punctata) has the potential to remediate wastewater and accumulate enormous amounts of starch for bioethanol production. Using systematical screening, we determined that the highest biomass and starch percentage of duckweed was obtained after uniconazole application. Uniconazole contributes to starch accumulation of duckweed, but the molecular mechanism is still unclear. To elucidate the mechanisms of high starch accumulation, in the study, the responses of L. punctata to uniconazole were investigated using a quantitative proteomic approach combined with physiological and biochemical analysis. A total of 3327 proteins were identified. Among these identified proteins, a large number of enzymes involved in endogenous hormone synthetic and starch metabolic pathways were affected. Notably, most of the enzymes involved in abscisic acid (ABA) biosynthesis showed up-regulated expression, which was consistent with the content variation. The increased endogenous ABA may up-regulate expression of ADP-glucose pyrophosphorylase to promote starch biosynthesis. Importantly, the expression levels of several key enzymes in the starch biosynthetic pathway were up-regulated, which supported the enzymatic assay results and may explain why there is increased starch accumulation. These generated data linked uniconazole with changes in expression of enzymes involved in hormone biosynthesis and starch metabolic pathways and elucidated the effect of hormones on starch accumulation. Thus, this study not only provided insights into the molecular mechanisms of uniconazole-induced hormone variation and starch accumulation but also highlighted the potential for duckweed to be feedstock for biofuel as well as for sewage treatment.

Preparation and Effect of Gamma Radiation on The Properties and Biodegradability of Poly(Styrene/Starch) Blends

NASA Astrophysics Data System (ADS)

Ali, H. E.; Abdel Ghaffar, A. M.

2017-01-01

Biodegradable blends based on Poly(styrene/starch) Poly(Sty/Starch) were prepared by the casting method using different contents of starch in the range of 0-20 wt% aiming at preparing disposable packaging materials. The prepared bio-blends were Characterized by Fourier transform infrared (FTIR), swelling behavior, mechanical properties, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). It was found that the swelling behavior slightly increased with increasing starch content and not exceeding 7.5%. The results showed that by increasing irradiation dose up to 5 kGy, the mechanical properties of the prepared PSty/10 wt% Starch blend film modified than other blend films, and hence it is selected. Also the water resistant increased, by irradiation of the selected PSty/10 wt% Starch blend film. The intermolecular hydrogen bonding interaction between Starch and PSty of the PSty/10 wt% Starch blend film promote a more homogenous blend film as shown in scanning electron microscopy (SEM). The prepared Poly(Sty/Starch) blends with different compositions and the selected irradiated PSty/10 wt% Starch blend were subjected to biodegradation in soil burial tests for 6 months using two different types of soils; agricultural and desert soils, then analyzed gravimetrically and by scanning electron microscopy (SEM). The results suggested that there is a possibility of using irradiated PSty/10 wt% Starch at a dose of 5 kGy as a potential candidate for packaging material.

Morphology, crystallinity, pasting, thermal and quality characteristics of starches from adzuki bean (Vigna angularis L.) and edible kudzu (Pueraria thomsonii Benth).

PubMed

Reddy, Chagam Koteswara; Luan, Fei; Xu, Baojun

2017-12-01

Starches were isolated from adzuki bean (Vigna angularis L.) and edible kudzu (Pueraria thomsonii Benth) and investigated for their physico-chemical, morphological, pasting, crystallinity, thermal and FT-IR spectroscopic characteristics. Statistical analysis of physico-chemical and functional characteristics showed significant (p<0.05) difference between isolated starches from adzuki bean and edible kudzu. The XRD pattern of starches from adzuki bean and edible kudzu showed A-type with reflections (2θ) at 15.0°, 17.03°, 17.89°, 23.18°and 15.12°, 17.03°, 17.77°, 23.3°, respectively. The starch granules from adzuki bean were smooth, round, oval to kidney or irregular while those of edible kudzu starch were spherical, hemispherical and polygonal. Edible kudzu starch exhibited high pasting temperature, gelatinization temperatures, enthalpy and less pasting parameters as compared to starch from adzuki bean. Peaks in FT-IR spectra of both starches shown its carbohydrate nature. Starch from adzuki bean showed high swelling power and solubility as compared to edible kudzu, and enhanced the swelling power and solubility of isolated starches with the temperature raised from 50°C and 90°C. Finally, this work offers data for the application of starches isolated from adzuki bean and edible kudzu that would be applicable for both food and non-food industries. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparative Emulsifying Properties of Octenyl Succinic Anhydride (OSA)-Modified Starch: Granular Form vs Dissolved State

PubMed Central

Marefati, Ali; Gutiérrez, Gemma; Wahlgren, Marie; Rayner, Marilyn

2016-01-01

The emulsifying ability of OSA-modified and native starch in the granular form, in the dissolved state and a combination of both was compared. This study aims to understand mixed systems of particles and dissolved starch with respect to what species dominates at droplet interfaces and how stability is affected by addition of one of the species to already formed emulsions. It was possible to create emulsions with OSA-modified starch isolated from Quinoa as sole emulsifier. Similar droplet sizes were obtained with emulsions prepared at 7% (w/w) oil content using OSA-modified starch in the granular form or molecularly dissolved but large differences were observed regarding stability. Pickering emulsions kept their droplet size constant after one month while emulsions formulated with OSA-modified starch dissolved exhibited coalescence. All emulsions stabilized combining OSA-modified starch in granular form and in solution showed larger mean droplet sizes with no significant differences with respect to the order of addition. These emulsions were unstable due to coalescence regarding presence of free oil. Similar results were obtained when emulsions were prepared by combining OSA-modified granules with native starch in solution. The degree of surface coverage of starch granules was much lower in presence of starch in solution which indicates that OSA-starch is more surface active in the dissolved state than in granular form, although it led to unstable systems compared to starch granule stabilized Pickering emulsions, which demonstrated to be extremely stable. PMID:27479315

Engineering yeasts for raw starch conversion.

PubMed

van Zyl, W H; Bloom, M; Viktor, M J

2012-09-01

Next to cellulose, starch is the most abundant hexose polymer in plants, an import food and feed source and a preferred substrate for the production of many industrial products. Efficient starch hydrolysis requires the activities of both α-1,4 and α-1,6-debranching hydrolases, such as endo-amylases, exo-amylases, debranching enzymes, and transferases. Although amylases are widely distributed in nature, only about 10 % of amylolytic enzymes are able to hydrolyse raw or unmodified starch, with a combination of α-amylases and glucoamylases as minimum requirement for the complete hydrolysis of raw starch. The cost-effective conversion of raw starch for the production of biofuels and other important by-products requires the expression of starch-hydrolysing enzymes in a fermenting yeast strain to achieve liquefaction, hydrolysis, and fermentation (Consolidated Bioprocessing, CBP) by a single organism. The status of engineering amylolytic activities into Saccharomyces cerevisiae as fermentative host is highlighted and progress as well as challenges towards a true CBP organism for raw starch is discussed. Conversion of raw starch by yeast secreting or displaying α-amylases and glucoamylases on their surface has been demonstrated, although not at high starch loading or conversion rates that will be economically viable on industrial scale. Once efficient conversion of raw starch can be demonstrated at commercial level, engineering of yeast to utilize alternative substrates and produce alternative chemicals as part of a sustainable biorefinery can be pursued to ensure the rightful place of starch converting yeasts in the envisaged bio-economy of the future.

Soybean cotyledon starch metabolism is sensitive to altered gravity conditions

NASA Technical Reports Server (NTRS)

Brown, C. S.; Piastuch, W. C.; Knott, W. M.

1994-01-01

We have demonstrated that etiolated soybean seedlings grown under the altered gravity conditions of clinorotation (1 rpm) and centrifugation (5xg) exhibit changes in starch metabolism. Cotyledon starch concentration was lower (-28%) in clinorotated plants and higher (+24%) in centrifuged plants than in vertical control plants. The activity of ADP-glucose pyrophosphorylase in the cotyledons was affected in a similar way, i.e. lower (-37%) in the clinorotated plants and higher (+22%) in the centrifuged plants. Other starch metabolic enzyme activities, starch synthase, starch phosphorylase and total hydrolase were not affected by the altered gravity treatments. We conclude that the observed changes in starch concentrations were primarily due to gravity-mediated differences in ADP-glucose pyrophosphorylase activity.

Study of changes induced in thermal properties of starch by incorporating Ag nanoparticles

NASA Astrophysics Data System (ADS)

Meena, Sharma, Annu

2018-05-01

This report presents the study of thermal properties of starch and Ag-starch nanocomposite films fabricated via chemical reduction method followed by solution casting. Thermo gravimetric analysis was utilized to investigate the effect of varying concentration of Ag nanoparticles on thermal stability and activation energy of starch. Activation energy that is the energy required for initialization of degradation process of starch comes out to be 238.9 kJ/mol which decreases to a value of 174.6 kJ/mol for Ag-starch nanocomposite film containing 0.50 wt% of Ag nanoparticles. Moreover the thermal stability of starch increases with the increasing concentration of Ag nanoparticles.

Preparation and Physical Properties of Starch Stearates of Low to High Degree of Substitution

USDA-ARS?s Scientific Manuscript database

Starch stearates of degree of substitution (DS) 0.07-2.40 were prepared by heating dry starch and vinyl stearate in the ionic liquid BMIM dca at 75 Degrees C. Starch stearate of low DS (0.07) was insoluble in water but formed a gel and absorbed over seven times its weight of water. Starch stearate...

Starch-Soybean Oil Composites with High Oil: Starch Ratios Prepared by Steam Jet Cooking

USDA-ARS?s Scientific Manuscript database

Aqueous mixtures of soybean oil and starch were jet cooked at oil:starch ratios ranging from 0.5:1 to 4:1 to yield dispersions of micron-sized oil droplets that were coated with a thin layer of starch at the oil-water interface. The jet cooked dispersions were then centrifuged at 2060 and 10,800 x ...

Enzymatic modification of corn starch with 4-α-glucanotransferase results in increasing slow digestible and resistant starch.

PubMed

Jiang, Huan; Miao, Ming; Ye, Fan; Jiang, Bo; Zhang, Tao

2014-04-01

In this study, partial 4-α-glucanotransferase (4αGT) treatment was used to modulate the fine structure responsible for the slow digestion and resistant property of starch. Normal corn starch modified using 4αGT for 4h showed an increase of slowly digestible starch from 9.40% to 20.92%, and resistant starch from 10.52 to 17.63%, respectively. The 4αGT treatment decreased the content of amylose from 32.6% to 26.8%. The molecular weight distribution and chain length distribution of 4αGT-treated starch showed a reduction of molecular weight and a great number of short (DP<13) and long (DP>30) chains through cleaving and reorganization of starch molecules. Both the short and long chain fractions of modified amylopectin were attributed to the low in vitro digestibility. The viscosity was inversely related to the digestibility of the 4αGT-treated starch. These results suggested that the 4αGT modified starch synthesized the novel amylopectin clusters with slow digestible and resistant character. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Synthesis, characterization, and antifungal evaluation of novel 1,2,3-triazolium-functionalized starch derivative.

PubMed

Tan, Wenqiang; Zhang, Jingjing; Luan, Fang; Wei, Lijie; Li, Qing; Dong, Fang; Guo, Zhanyong

2017-08-01

1,2,3-Triazolium-functionalized starch derivative was obtained by straightforward quaternization of the synthesized starch derivative bearing 1,2,3-triazole with benzyl bromide by combining the robust attributes of cuprous-catalyzed azide-alkyne cycloaddition. These novel starch derivatives were characterized by FTIR, UV-vis, 1 H NMR, 13 C NMR, and elemental analysis. Their antifungal activities against Colletotrichum lagenarium, Watermelon fusarium, and Phomopsis asparagi were investigated by hypha measurement in vitro. The fungicidal assessment revealed that compared with starch and starch derivative bearing 1,2,3-triazole with inhibitory indices of below 15% at 1.0mg/mL, 1,2,3-triazolium-functionalized starch derivative had superior antifungal activity with inhibitory rates of over 60%. Especially, the best inhibitory index of 1,2,3-triazolium-functionalized starch derivative against Colletotrichum lagenarium attained 90% above at 1.0mg/mL. The results obviously showed that quaternization of 1,2,3-triazole with benzyl bromide could effectively enhance antifungal activity of the synthesized starch derivatives. The synthetic strategy described here could be utilized for the development of starch as novel antifungal biomaterial. Copyright © 2017 Elsevier B.V. All rights reserved.

Poly(Lactic Acid) Filled with Cassava Starch-g-Soybean Oil Maleate

PubMed Central

Kiangkitiwan, Nopparut; Srikulkit, Kawee

2013-01-01

Poly(lactic acid), PLA, is a biodegradable polymer, but its applications are limited by its high cost and relatively poorer properties when compared to petroleum-based plastics. The addition of starch powder into PLA is one of the most promising efforts because starch is an abundant and cheap biopolymer. However, the challenge is the major problem associated with poor interfacial adhesion between the hydrophilic starch granules and the hydrophobic PLA, leading to poorer mechanical properties. In this paper, soybean oil maleate (SOMA) was synthesized by grafting soybean oil with various weight percents of maleic anhydride (MA) using dicumyl peroxide (DCP) as an initiator. Then, SOMA was employed for the surface modifying of cassava starch powder, resulting in SOMA-g-STARCH. The obtained SOMA-g-STARCH was mixed with PLA in various weight ratios using twin-screw extruder, resulting in PLA/SOMA-g-STARCH. Finally, the obtained PLA/SOMA-g-STARCH composites were prepared by a compression molding machines. The compatibility, thermal properties, morphology properties, and mechanical properties were characterized and evaluated. The results showed that the compatibility, surface appearance, and mechanical properties at 90 : 10 and 80 : 20 ratios of PLA/SOMA-g-STARCH were the best. PMID:24307883

Hydrogen/deuterium (H/D) exchange of gelatinized starch studied by two-dimensional (2D) near-infrared (NIR) correlation spectroscopy

NASA Astrophysics Data System (ADS)

Shinzawa, Hideyuki; Mizukado, Junji

2018-05-01

Hydrogen/deuterium (H/D) exchange of gelatinized starch was probed by in-situ near-infrared (NIR) monitoring coupled with two-dimensional (2D) correlation spectroscopy. Gelatinized starch undergoes spontaneous H/D exchange in D2O. During the substitution, the exchange rate essentially becomes different depending on solvent accessibility of various parts of the molecule. Thus, by analyzing the change in the NIR feature observed during the substitution, it becomes possible to sort out local structure and dynamics of the system. 2D correlation analysis of the time-dependent NIR spectra reveals the presence of different local structure of the starch, each having different solvent accessibility. For example, during the H/D exchange, the D2O is first absorbed by starch molecules especially around the surface area between the starch and water, where the water molecules are weakly interacted with the starch molecules. This absorption is quickly followed by the development of HDO species. Further absorption of the D2O results in the penetration of the molecules inside the starch and eventually develops the relatively strong interaction between the HDO and starch molecules because of the presence of dominant starch molecules.

Supply of avocado starch (Persea americana mill) as bioplastic material

NASA Astrophysics Data System (ADS)

Ginting, M. H. S.; Hasibuan, R.; Lubis, M.; Alanjani, F.; Winoto, F. A.; Siregar, R. C.

2018-02-01

The purpose of this study was to determine the effect of time precipitation of avocado slurry seed to yield of starch. Starch analysis included starch content, moisture content, amylose content, amylopectin content, ash content, protein content, fat content, Fourier transform infra red analysis and rapid visco analyzer. Supply of starch from avocado seeds was used by extraction method. Every one hundred grams of avocado slurry was precipitated by gravity with variations for 4 hours, 8 hours, 12 hours, 16 hours, 20 hours and 24 hours. The Starch yield was washed, and dried using oven at 70°C for 30 minutes. Starch yield was the highest as 24.20 gram at 24 hours. The result of starch characterization was 73.62%, water content 16.6%, amylose 0.07%, amylopectin 73.55%, ash content 0.23%, protein content 2.16%, fat content 1.09%. Rapid visco analyzer obtained at 91.33°C of gelatinization temperature. Scanning electron microscopy analyzes obtained 20 μm oval-shaped starch granules. Fourier Transform Infra Red analysis of starch obtained the peak spectrum of O-H group of alcohols, C-H alkanes and C-O ether.

Hypolipidemic effects of starch and γ-oryzanol from wx/ae double-mutant rice on BALB/c.KOR-Apoe(shl) mice.

PubMed

Nakaya, Makoto; Shojo, Aiko; Hirai, Hiroaki; Matsumoto, Kenji; Kitamura, Shinichi

2013-01-01

waxy/amylose-extender (wx/ae) double-mutant japonica rice (Oryza sativa L.) produces resistant starch (RS) and a large amount of γ-oryzanol. Our previous study has shown the hypolipidemic effect of wx/ae brown rice on mice. To identify the functional constituents of the hypolipidemic activity in wx/ae rice, we prepared pure wx/ae starch and γ-oryzanol from wx/ae rice and investigated their effect on the lipid metabolism in BALB/c.KOR/Stm Slc-Apoe(shl) mice. The mice were fed for 3 weeks a diet containing non-mutant rice starch, non-mutant rice starch plus γ-oryzanol, wx/ae starch, or wx/ae starch plus γ-oryzanol. γ-Oryzanol by itself had no effect on the lipid metabolism, and wx/ae starch prevented an accumulation of triacylglycerol (TAG) in the liver. Interestingly, the combination of wx/ae starch plus γ-oryzanol not only prevented a TAG accumulation in the liver, but also partially suppressed the rise in plasma TAG concentration, indicating that wx/ae starch and γ-oryzanol could have a synergistic effect on the lipid metabolism.

Effect of high hydrostatic pressure on the supramolecular structure of corn starch with different amylose contents.

PubMed

Yang, Zhi; Swedlund, Peter; Hemar, Yacine; Mo, Guang; Wei, Yanru; Li, Zhihong; Wu, Zhonghua

2016-04-01

Corn starches with amylose contents ranging from 0 to 80% were suspended in 60 wt% water or ethanol and subjected to high hydrostatic pressure (HHP) up to 600 MPa. The impact of HHP treatment on the granule morphology, lamellae structures, and crystalline characteristics were examined with a combination of SAXS, WAXS and optical microscopy. All starch dispersed in water showed a decrease in area of the lamellar peak in the SAXS data at q∼0.6 nm(-1). The lamellae thickness (d) increased for pressurized waxy, normal, and Gelose80 corn starches, suggesting water is forced into starch lamellae during HHP. However, for Gelose50 corn starch, the d remained constant over the whole pressure range and light microscopy showed no obvious granule swelling. WAXS studies demonstrated that HHP partially converted A-type starches (waxy and normal corn) to starches with a faint B-type pattern while starches with a B+V-type pattern (Gelose50 and Gelose80), were not affected by HHP. All corn starches suspended in ethanol showed no detectable changes in either granule morphology, or the fractal, the lamellae, and the crystalline structures. Copyright © 2016 Elsevier B.V. All rights reserved.

Physicochemical and digestibility properties of double-modified banana ( Musa paradisiaca L.) starches.

PubMed

Carlos-Amaya, Fandila; Osorio-Diaz, Perla; Agama-Acevedo, Edith; Yee-Madeira, Hernani; Bello-Pérez, Luis Arturo

2011-02-23

Banana starch was chemically modified using single (esterification or cross-linking) and dual modification (esterification-cross-linking and cross-linking-esterification), with the objective to increase the slowly digestible starch (SDS) and resistant starch (RS) concentrations. Physicochemical properties and in vitro digestibility were analyzed. The degree of substitution of the esterified samples ranged from 0.006 to 0.020. The X-ray diffraction pattern of the modified samples did not show change; however, an increase in crystallinity level was determined (from 23.79 to 32.76%). The ungelatinized samples had low rapidly digestible starch (RDS) (4.23-9.19%), whereas the modified starches showed an increase in SDS (from 10.79 to 16.79%) and had high RS content (74.07-85.07%). In the cooked samples, the esterified starch increased the SDS content (21.32%), followed by cross-linked starch (15.13%). Dual modified starch (cross-linked-esterified) had the lowest SDS content, but the highest RS amount. The esterified and cross-linked-esterified samples had higher peak viscosity than cross-linked and esterified-cross-linked. This characteristic is due to the fact that in dual modification, the groups introduced in the first modification are replaced by the functional group of the second modification. Temperature and enthalpy of gelatinization decreased in modified starches (from 75.37 to 74.02 °C and from 10.42 to 8.68 J/g, respectively), compared with their unmodified starch (76.15 °C and 11.05 J/g). Cross-linked-esterified starch showed the lowest enthalpy of gelatinization (8.68 J/g). Retrogradation temperature decreased in modified starches compared with unmodified (59.04-57.47 °C), but no significant differences were found among the modified samples.

Use of enzymes to minimize the rheological dough problems caused by high levels of damaged starch in starch-gluten systems.

PubMed

Barrera, Gabriela N; León, Alberto E; Ribotta, Pablo D

2016-05-01

During wheat milling, starch granules can experience mechanical damage, producing damaged starch. High levels of damaged starch modify the physicochemical properties of wheat flour, negatively affecting the dough behavior as well as the flour quality and cookie and bread making quality. The aim of this work was to evaluate the effect of α-amylase, maltogenic amylase and amyloglucosidase on dough rheology in order to propose alternatives to reduce the issues related to high levels of damaged starch. The dough with a high level of damaged starch became more viscous and resistant to deformations as well as less elastic and extensible. The soluble fraction of the doughs influenced the rheological behavior of the systems. The α-amylase and amyloglucosidase reduced the negative effects of high damaged starch contents, improving the dough rheological properties modified by damaged starch. The rheological behavior of dough with the higher damaged-starch content was related to a more open gluten network arrangement as a result of the large size of the swollen damaged starch granules. We can conclude that the dough rheological properties of systems with high damaged starch content changed positively as a result of enzyme action, particularly α-amylase and amyloglucosidase additions, allowing the use of these amylases and mixtures of them as corrective additives. Little information was reported about amyloglucosidase activity alone or combined with α-amylase. The combinations of these two enzymes are promising to minimize the negative effects caused by high levels of damaged starch on product quality. More research needs to be done on bread quality combining these two enzymes. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Physicochemical and microstructural characterisation of green gram and foxtail millet starch gels.

PubMed

Nagaprabha, P; Devisetti, Rajesh; Bhattacharya, Sila

2018-02-01

The starch and starch gels from green gram (GG) and foxtail millet (FM) were characterised for their physicochemical, thermal and microstructural characteristics; the features of shape and size were determined by image analysis. Both GG and FM formed well-set gels at 9% concentration of starch. The fracture strain of the gels was between 78 and 80% indicating non-brittle gels. The peak temperatures of the native flour of GG (74.9 °C) and FM (75.7 °C) were significantly higher than their corresponding starch samples (72.2 and 75.0 °C). The conclusion temperatures of the FM native flour (81.2 °C) and starch (79.4 °C) samples were higher than the native GG flour (79.9 °C) and GG starch (77.1 °C) samples. Starches were nearly spherical as the roundness values were between 0.88 and 0.95. Green gram starch was pentagonal having an average diameter of 3.9-9.2 µm while foxtail millet starch was spherical with a diameter of 4.9-10.1 µm. The freeze-dried GG and FM starch gels showed cellular structure containing organised hexagonal pores, bound by thin pore walls; the GG starch gels deviated from the circular shape as they had the highest elongation value of 4.21. The thicker pore walls were observed for GG starch gels (0.88 μm) compared to that of FM samples (0.57 μm). The higher pore wall thickness in the case of GG gel showed the formation of junction zones.

Maltose Biochemistry and Transport in Plant Leaves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharkey, Thomas D

Starch is a desirable plant product for both food and biofuel. Leaf starch is ideal for use in biofuels because it does not compete with grain starch, which is used for food. Starch is accumulated in plant leaves during the day and broken down at night. If we can manipulate leaf starch breakdown it may be possible to design a plant that provides both grain starch for food and leaf starch for biofuel. The pathway of leaf starch breakdown was not known when this work started. Preliminary evidence had shown that maltose was the primary product of leaf starch breakdownmore » (Weise, Weber & Sharkey, 2004) and that it was metabolized by a disproportionating enzyme called amylomaltase but given the initials DPE2 (Lu & Sharkey, 2004). In this work we showed that only one form of maltose was metabolically active (Weise et al., 2005a) and that maltose was located in two different places when the amylomaltase was knocked out but only inside the chloroplast when the maltose transporter was knocked out (Lu et al., 2006a). This allowed us to estimate the energetics of maltose export and to show that maltose export is more efficient than glucose export (Weise et al., 2005b). We examined how daylength affected starch breakdown rate and found that starch breakdown rate could respond to changes in daylength within one day (Lu, Gehan & Sharkey, 2005). We also were able to show a second starch breakdown pathway by chloroplastic starch phosphorylase (Weise et al., 2006). Work to this point was summarized in a review (Lu & Sharkey, 2006). We were able to show that the amylomaltase in plants could substitute for the amylomaltase in bacteria (Lu et al., 2006b). In this paper we also showed the importance of a second enzyme called alpha-glucan phosphorylase in starch breakdown. Finally, we were able to determine the enzymatic mechanism of the amylomaltase (Steichen, Petty & Sharkey, 2008). These results have laid the groundwork for manipulating plants for improved biofuel production.« less

Soft and Hard Textured Wheat Differ in Starch Properties as Indicated by Trimodal Distribution, Morphology, Thermal and Crystalline Properties

PubMed Central

Kumar, Rohit; Kumar, Aman; Sharma, Nand Kishor; Kaur, Navneet; Chunduri, Venkatesh; Chawla, Meenakshi; Sharma, Saloni; Singh, Kashmir; Garg, Monika

2016-01-01

Starch and proteins are major components in the wheat endosperm that affect its end product quality. Between the two textural classes of wheat i.e. hard and soft, starch granules are loosely bound with the lipids and proteins in soft wheat due to higher expression of interfering grain softness proteins. It might have impact on starch granules properties. In this work for the first time the physiochemical and structural properties of different sized starch granules (A-, B- and C-granules) were studied to understand the differences in starches with respect to soft and hard wheat. A-, B- and C-type granules were separated with >95% purity. Average number and proportion of A-, B-, and C-type granules was 18%, 56%, 26% and 76%, 19%, 5% respectively. All had symmetrical birefringence pattern with varied intensity. All displayed typical A-type crystallites. A-type granules also showed V-type crystallinity that is indicative of starch complexes with lipids and proteins. Granules differing in gelatinization temperature (ΔH) and transition temperature (ΔT), showed different enthalpy changes during heating. Substitution analysis indicated differences in relative substitution pattern of different starch granules. Birefringence, percentage crystallinity, transmittance, gelatinization enthalpy and substitution decreased in order of A>B>C being higher in hard wheat than soft wheat. Amylose content decreased in order of A>B>C being higher in soft wheat than hard wheat. Reconstitution experiment showed that starch properties could be manipulated by changing the composition of starch granules. Addition of A-granules to total starch significantly affected its thermal properties. Effect of A-granule addition was higher than B- and C-granules. Transmittance of the starch granules paste showed that starch granules of hard wheat formed clear paste. These results suggested that in addition to differences in protein concentration, hard and soft wheat lines have differences in starch composition also. PMID:26824830

Soft and Hard Textured Wheat Differ in Starch Properties as Indicated by Trimodal Distribution, Morphology, Thermal and Crystalline Properties.

PubMed

Kumar, Rohit; Kumar, Aman; Sharma, Nand Kishor; Kaur, Navneet; Chunduri, Venkatesh; Chawla, Meenakshi; Sharma, Saloni; Singh, Kashmir; Garg, Monika

2016-01-01

Starch and proteins are major components in the wheat endosperm that affect its end product quality. Between the two textural classes of wheat i.e. hard and soft, starch granules are loosely bound with the lipids and proteins in soft wheat due to higher expression of interfering grain softness proteins. It might have impact on starch granules properties. In this work for the first time the physiochemical and structural properties of different sized starch granules (A-, B- and C-granules) were studied to understand the differences in starches with respect to soft and hard wheat. A-, B- and C-type granules were separated with >95% purity. Average number and proportion of A-, B-, and C-type granules was 18%, 56%, 26% and 76%, 19%, 5% respectively. All had symmetrical birefringence pattern with varied intensity. All displayed typical A-type crystallites. A-type granules also showed V-type crystallinity that is indicative of starch complexes with lipids and proteins. Granules differing in gelatinization temperature (ΔH) and transition temperature (ΔT), showed different enthalpy changes during heating. Substitution analysis indicated differences in relative substitution pattern of different starch granules. Birefringence, percentage crystallinity, transmittance, gelatinization enthalpy and substitution decreased in order of A>B>C being higher in hard wheat than soft wheat. Amylose content decreased in order of A>B>C being higher in soft wheat than hard wheat. Reconstitution experiment showed that starch properties could be manipulated by changing the composition of starch granules. Addition of A-granules to total starch significantly affected its thermal properties. Effect of A-granule addition was higher than B- and C-granules. Transmittance of the starch granules paste showed that starch granules of hard wheat formed clear paste. These results suggested that in addition to differences in protein concentration, hard and soft wheat lines have differences in starch composition also.

Comparison of physicochemical and functional properties of flour and starch extract in different methods from Africa locust bean (Parkia biglobosa) seeds.

PubMed

Sankhon, Abdoulaye; Amadou, Issoufou; Yao, Wei-Rong; Wang, Heya; Qian, He; Sangare, Moustapha

2014-01-01

African locust bean tree is an important food tree for both human and livestock such as husks and pods. It plays a very vital role in the rural areas. The aim of this study was to evaluate some physicochemical, mineral characteristics and functional properties of flour and starch extract produced from Parkia biglobosa seeds, using different methods. Three different methods were used for starch extraction in other to get the Starch yield (%),composition analysis for; moisture, protein, fat, ash and fiber contents of flour and starch extracts from Parkia biglobosa were determined on dry basis (db), by AACC method, color and PH value measurements was carried out using color flex spectrocolorimeter, and the official method of AOAC respectively. Pasting properties was determined and X-ray powder starch diffraction was used to examine the crystalline property of flour and starch extract. Gelatinization characteristics and in vitro starch digestibility were also determined, test results were processed using one-way analysis of variance (ANOVA). Flour showed higher (P < 0.05), moisture content, fat, carbohydrate, amylopectine, and protein content than starch, while amylose content of this starch was higher (P<0.05). Phosphorus, sodium, magnesium, and potassium minerals content were higher in flour than starch. Pasting properties, gelatinisation, color, pH values, water and oil absorption capacity content of the flour were found to be higher than that of starch. The pasting characteristics showed a decrease of viscosity, final viscosity, set back value, breakdown, and pasting temperature of flour when compared to that of starch. From our results, we speculate that flour from native Parkia biglobosa grown in Guinea under controlled environmental conditions could be considered as an ideal RS material, whereas the extract Parkia starch could be an ideal SDS material. Therefore, these may offer an interesting alternative for food developers, depending on their characteristics and functional properties.

Application of oxidized starch in bake-only chicken nuggets.

PubMed

Purcell, Sarah; Wang, Ya-Jane; Seo, Han-Seok

2014-05-01

There is a need to reduce the fat content in fried foods because of increasing health concerns from consumers. Oxidized starches have been utilized in many coating applications for their adhesion ability. However, it is not known if they perform similarly in bake-only products. This study investigated the application of oxidized starch in bake-only chicken nuggets. Oxidized starches were prepared from 7 starches and analyzed for gelatinization and pasting properties. Chicken nuggets were prepared using batter containing wheat flour, oxidized starch, salt, and leavening agents prior to steaming, oven baking, freezing, and final oven baking for sensory evaluation. All nuggets were analyzed for hardness by a textural analyzer, crispness by an acoustic sound, and sensory characteristics by a trained panel. The oxidation level used in the study did not alter the gelatinization temperature of most starches, but increased the peak pasting viscosity of both types of corn and rice starches and decreased that of tapioca and potato starches. There were slight differences in peak force and acoustic reading between some treatments; however, the differences were not consistent with starch type or amylose content. There was no difference among the treatments as well as between the control with wheat flour and the treatments partially replaced with oxidized starches in all sensory attributes of bake-only nuggets evaluated by the trained panel. There is a need to reduce the fat content in fried food, such as chicken nuggets, because of increasing childhood obesity. Oxidized starches are widely used in coating applications for their adhesion ability. This study investigated the source of oxidized starches in steam-baked coated nuggets for their textural and sensorial properties. The findings from this research will provide an understanding of the contributions of starch source and oxidation to the texture and sensory attributes of bake-only nuggets, and future directions to improve the batter formulation for bake-only nuggets. © 2014 Institute of Food Technologists®

Some physicochemical and rheological properties of starch isolated from avocado seeds.

PubMed

Chel-Guerrero, Luis; Barbosa-Martín, Enrique; Martínez-Antonio, Agustino; González-Mondragón, Edith; Betancur-Ancona, David

2016-05-01

Seeds from avocado (Persea americana Miller) fruit are a waste byproduct of fruit processing. Starch from avocado seed is a potential alternative starch source. Two different extraction solvents were used to isolate starch from avocado seeds, functional and rheological characteristics measured for these starches, and comparisons made to maize starch. Avocado seed powder was suspended in a solution containing 2 mM Tris, 7.5 mM NaCl and 80 mM NaHSO3 (solvent A) or sodium bisulphite solution (1500 ppm SO2, solvent B). Solvent type had no influence (p>0.05) on starch properties. Amylose content was 15-16%. Gelatinization temperature range was 56-74 °C, peak temperature was 65.7 °C, and transition enthalpy was 11.4-11.6J/g. At 90 °C, solubility was 19-20%, swelling power 28-30 g water/g starch, and water absorption capacity was 22-24 g water/g starch. Pasting properties were initial temperature 72 °C; maximum viscosity 380-390 BU; breakdown -2 BU; consistency 200 BU; and setback 198 BU. Avocado seed starch dispersions (5% w/v) were characterized as viscoelastic systems, with G'>G″. Avocado seed starch has potential applications as a thickening and gelling agent in food systems, as a vehicle in pharmaceutical systems and an ingredient in biodegradable polymers for food packaging. Copyright © 2016. Published by Elsevier B.V.

Characteristics of plastids responsible for starch synthesis in developing pea embryos.

PubMed

Smith, A M; Quinton-Tulloch, J; Denyer, K

1990-03-01

The nature of the starch-synthesising plastids in developing pea (Pisum sativum L.) embryos has been investigated. Chlorophyll and starch were distributed throughout the cotyledon during development. Chlorophyll content increased initially, then showed little change up to the point of drying out of the embryo. Starch content per embryo increased dramatically throughout development. The chlorophyll content per unit volume was highest on the outer edge of the cotyledon, while the starch content was highest on inner face. Nycodenz gradients, which fractionated mechanically-prepared plastids according to their starch content, failed to achieve any significant separation of plastids rich in starch and ADP-glucose pyrophosphorylase from those rich in chlorophyll and a Calvin-cycle marker enzyme, NADP-glyceraldehyde-3-phosphate dehydrogenase. However, material that was not sufficiently dense to enter the gradients was enriched in activity of the Calvin-cycle marker enzyme relative to that of ADP-glucose pyrophosphorylase. Nomarski and epi-fluorescence microscopy showed that intact, isolated plastids, including those with very large starch grains, invariably contained chlorophyll in stromal structures peripheral to the starch grain. We suggest that the starch-storing plastids of developing pea embryos are derived directly from chloroplasts, and retain chloroplast-like characteristics throughout their development. Developing pea embryos also contain chloroplasts which store little or no starch. These are probably located primarily on the outer edge of the cotyledons where there is sufficient light for photosynthesis at some stages of development.

Modification of cassava starch using combination process lactic acid hydrolysis and micro wave heating to increase coated peanut expansion quality

NASA Astrophysics Data System (ADS)

Sumardiono, Siswo; Pudjihastuti, Isti; Jos, Bakti; Taufani, Muhammad; Yahya, Faad

2017-05-01

Modified cassava starch is very prospective products in the food industry. The main consideration of this study is the increasing volume of imported wheat and the demand for modified cassava starch industry. The purpose of this study is the assessing of lactic acid hydrolysis and microwave heating impact to the physicochemical and rheological properties of modified cassava starch, and test applications of modified cassava starch to coated peanut expansion quality. Experimental variables include the concentration of lactic acid (0.5% w/w, 1% w/w; 2% w/w), a time of hydrolysis (15, 30, 45 minutes), a time of microwave heating (1, 2, 3 hours). The research step is by dissolving lactic acid using aquadest in the stirred tank reactor, then added cassava starch. Hydrolysed cassava starch was then heated by microwave. Physicochemical properties and rheology of the modified cassava starch is determined by the solubility, swelling power, and test congestion. The optimum obtained results indicate that solubility, swelling power, congestion test, respectively for 19.75%; 24.25% and 826.10% in the hydrolysis treatment for 15 minutes, 1% w lactic acid and microwave heating 3 hours. The physicochemical and rheological properties of modified cassava starch have changed significantly when compared to the native cassava starch. Furthermore, these modified cassava starch are expected to be used for the substitution of food products.

Starch-based xerogels: Effect of acetylation on Physicochemical and rheological properties.

PubMed

Kemas, Chinwe U; Ngwuluka, Ndidi C; Ochekpe, Nelson A; Nep, Elijah I

2017-05-01

This study was aimed at evaluating the physicochemical and rheological properties of starch-based xerogels. The starch from the shoots of Borassus aethiopium was physically modified by xerogelization, and chemically by acetylation, and combination of acetylation and xerogelization. The solubility, swelling and syneresis of the starches were determined by gravimetric techniques. Evaluation of the native starch and derivatives was done using microscopy, Fourier transform infra-red (FTIR), x-ray diffractometry (XRD), and 1 H NMR spectroscopy. Rheological evaluation was done on 10%w/v dispersions using a Bohlin Gemini rheometer (fitted with a 55mm and 2° cone and plate geometry with gap of 70). The diffractograms displayed three peaks, centered on 2θ=15.3, 17.2 and 23.1° for the native and the starch acetate while the xerogel and the starch acetate xerogel were amorphous. The 1 H NMR and FTIR confirmed the presence of acetyl groups at about 2.05ppm and 1720cm -1 , respectively. Acetylation of the native starch resulted in improvement of solubility. The starch acetate-xerogel sample formed viscoelastic gels without the need for heating. Acetylation and/or xerogelization of the native starch inhibited syneresis. Starch acetate-xerogels, may find application as stabilizer or suspending agent in liquid food and pharmaceutical formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

OsBT1 encodes an ADP-glucose transporter involved in starch synthesis and compound granule formation in rice endosperm

PubMed Central

Li, Sanfeng; Wei, Xiangjin; Ren, Yulong; Qiu, Jiehua; Jiao, Guiai; Guo, Xiuping; Tang, Shaoqing; Wan, Jianmin; Hu, Peisong

2017-01-01

Starch is the main storage carbohydrate in higher plants. Although several enzymes and regulators for starch biosynthesis have been characterized, a complete regulatory network for starch synthesis in cereal seeds remains elusive. Here, we report the identification and characterization of the rice Brittle1 (OsBT1) gene, which is expressed specifically in the developing endosperm. The osbt1 mutant showed a white-core endosperm and a significantly lower grain weight than the wild-type. The formation and development of compound starch granules in osbt1 was obviously defective: the amyloplast was disintegrated at early developmental stages and the starch granules were disperse and not compound in the endosperm cells in the centre region of osbt1 seeds. The total starch content and amylose content was decreased and the physicochemical properties of starch were altered. Moreover, the degree of polymerization (DP) of amylopectin in osbt1 was remarkably different from that of wild-type. Map-based cloning of OsBT1 indicated that it encodes a putatively ADP-glucose transporter. OsBT1 coded protein localizes in the amyloplast envelope membrane. Furthermore, the expression of starch synthesis related genes was also altered in the osbt1 mutant. These findings indicate that OsBT1 plays an important role in starch synthesis and the formation of compound starch granules. PMID:28054650

Utilization of modified starch from avocado (Persea americana Mill.) seed in cream soup production

NASA Astrophysics Data System (ADS)

Cornelia, M.; Christianti, A.

2018-01-01

Avocado (Persea americana Mill.) seed was often seen as waste and underutilized resources, especially in the food industry. The aim of this research was to modify the structure of avocado seed starch using the cross-linking method, to improve the viscosity stability in the cream soup. In the preliminary research, starch was isolated from the seed and modified by STPP (sodium tripolyphosphate) with 2%, 4%, and 6% concentration and were reacted for 1, 2, and 3 hours. Starches were analyzed for moisture and ash content, paste clarity, gel strength, swelling power, solubility, yield, and degree of whiteness. Based on the analysis results, the best reaction time and STPP concentration was 6% at 1 hour reaction time. Native starch and the best-modified starch were applied in the cream soup and compared with commercial cream soup. Cream soups were analyzed for viscosity stability using viscometer in 0, 1, 3, and 5 hours after storage in room temperature. The result showed that cream soup using modified starch has better viscosity stability than native starch and commercial cream soup after 5 hours storage, which was 181.7 ± 4.85 cP. Sensory analysis showed that cream soup using modified starch was more acceptable than the others. Avocado seed modified starch has phosphate group that strengthen the starch chain to prevent viscosity breakdown.

Distribution of branches in whole starches from maize mutants deficient in starch synthase III.

PubMed

Zhu, Fan; Bertoft, Eric; Seetharaman, Koushik

2014-05-21

An earlier study explored the possibility of analyzing the distribution of branches directly in native, whole starch without isolating the amylopectin component. The aim of this study was to explore if this approach can be extended to include starch mutants. Whole starches from du1 maize mutants deficient in starch synthase III (SSIII) with amylose content of ∼30-40% were characterized and compared with the wild type of the common genetic background W64A. Clusters were produced from whole starch by hydrolysis with α-amylase of Bacillus amyloliquefaciens. Their compositions of building blocks and chains were analyzed further by complete α-amylolysis and by debranching, respectively, whereafter the products were subjected to gel permeation and anion exchange chromatography. The size and structure of the clusters were compared with those of their isolated amylopectin component. Whereas the whole starch of the wild type sample had a branched structure similar to that of its amylopectin component, the results showed that the du1 mutation resulted in more singly branched building blocks in the whole starch compared to the isolated amylopectin. This suggested that amylose and/or intermediate materials in whole du1 starches likely contributed to the composition of branches. This study explored an alternative procedure to characterize the composition of branches in the whole starch without fractionating the components.

Gelatinization and freeze-concentration effects on recrystallization in corn and potato starch gels.

PubMed

Ronda, Felicidad; Roos, Yrjö H

2008-04-07

Freeze-concentration of starch gels was controlled by temperature and gelatinization with glucose and lactose. The aim of the study was to evaluate the effects of freezing temperature and gel composition on starch recrystallization behaviour of corn and potato starch gels (water content 70%, w/w) in water or glucose or lactose (10%, w/w) solutions. Starch gels were obtained by heating in differential scanning calorimetry (DSC). Samples of starch gels were frozen at -10 degrees C, -20 degrees C and -30 degrees C for 24h and, after thawing, stored at +2 degrees C for 0, 1, 2, 4 and 8 days. The extent of starch recrystallization was taken from the enthalpy of melting of the recrystallized starch by DSC. Freezing temperatures, glucose, lactose and the origin of the starch affected the recrystallization behaviour greatly. The recrystallization of amorphous starch during storage was enhanced by freeze-concentration of gels at temperatures above T'(m). Molecular mobility was enhanced by unfrozen water and consequently molecular rearrangements for nucleation could take place. Further storage at a higher temperature enhanced the growth and the maturation of crystals. In particular, glucose decreased the T'(m) of the gels and consequently lower freezing temperatures were needed to reduce enhanced recrystallization during storage. Freeze-concentration temperatures also showed a significant effect on the size and the perfection of crystals formed in starch recrystallization.

Alkali-induced changes in functional properties and in vitro digestibility of wheat starch: the role of surface proteins and lipids.

PubMed

Wang, Shujun; Luo, Heyang; Zhang, Jian; Zhang, Yan; He, Zhonghu; Wang, Shuo

2014-04-23

The bread wheat starch was treated with 0.025 and 0.0625 M NaOH solution for 1, 2, and 3 weeks at 30 °C, and the changes in functionality and in vitro digestibility were evaluated. NaOH treatment reduced protein and lipid contents of wheat starch from 0.46 to 0.20% and from 0.59 to 0.25%, respectively. No significant changes were observed in the amylose content, relative crystallinity, and short-range order of double helices, but there was evidence showing that morphology of some starch granules was altered. The swelling power and starch solubility of wheat starch increased from 11.4 to 14.1 g/g and from 10.9 to 22.1%, respectively. The thermal transition temperatures were increased greatly, but the enthalpy change remained largely unchanged. Alkali treatment greatly decreased the pasting temperature, but the pasting viscosities were altered in different ways. The resistant starch (RS) content of wheat starch was decreased significantly from 69.9 to 45.2%, while the starch that is digested slowly (SDS) content was increased greatly from 13.6 to 34.5%. Our results showed that alkali treatment can significantly alter the functionality and in vitro digestibility of wheat starch granules by removing the surface proteins and lipids rather than significantly altering the internal structure of starch granules.

The priming of storage glucan synthesis from bacteria to plants: current knowledge and new developments.

PubMed

D'Hulst, Christophe; Mérida, Angel

2010-10-01

Starch is the main polymer in which carbon and energy are stored in land plants, algae and some cyanobacteria. It plays a crucial role in the physiology of these organisms and also represents an important polymer for humans, in terms of both diet and nonfood industry uses. Recent efforts have elucidated most of the steps involved in the synthesis of starch. However, the process that initiates the synthesis of the starch granule remains unclear. Here, we outline the similarities between the synthesis of starch and the synthesis of glycogen, the other widespread and abundant glucose-based polymer in living cells. We place special emphasis on the mechanisms of initiation of the glycogen granule and current knowledge concerning the initiation of the starch granule. We also discuss recent discoveries regarding the function of starch synthases in the priming of the starch granule and possible interactions with other elements of the starch synthesis machinery.

Resistant Starch Regulates Gut Microbiota: Structure, Biochemistry and Cell Signalling.

PubMed

Yang, Xiaoping; Darko, Kwame Oteng; Huang, Yanjun; He, Caimei; Yang, Huansheng; He, Shanping; Li, Jianzhong; Li, Jian; Hocher, Berthold; Yin, Yulong

2017-01-01

Starch is one of the most popular nutritional sources for both human and animals. Due to the variation of its nutritional traits and biochemical specificities, starch has been classified into rapidly digestible, slowly digestible and resistant starch. Resistant starch has its own unique chemical structure, and various forms of resistant starch are commercially available. It has been found being a multiple-functional regulator for treating metabolic dysfunction. Different functions of resistant starch such as modulation of the gut microbiota, gut peptides, circulating growth factors, circulating inflammatory mediators have been characterized by animal studies and clinical trials. In this mini-review, recent remarkable progress in resistant starch on gut microbiota, particularly the effect of structure, biochemistry and cell signaling on nutrition has been summarized, with highlights on its regulatory effect on gut microbiota. © 2017 The Author(s). Published by S. Karger AG, Basel.

Development of native and modified banana starch nanoparticles as vehicles for curcumin.

PubMed

Acevedo-Guevara, Leonardo; Nieto-Suaza, Leonardo; Sanchez, Leidy T; Pinzon, Magda I; Villa, Cristian C

2018-05-01

In recent years, starch nanoparticles have been of great interest for drug delivery due to their relatively easy synthesis, biocompatibility, and vast amount of botanical sources. Native and acetylated starch obtained from green bananas were used for synthesis of curcumin-loaded starch nanoparticles. Mean particle size, encapsulation efficiency, and curcumin release in simulated gastric and intestinal fluids were studied. Both nanosystems showed sizes lower than 250 nm and encapsulation efficiency above 80%, with acetylated banana starch nanoparticles having the capacity to encapsulate more curcumin molecules. Both FTIR and XRD analyses showed that starch acetylation allows stronger hydrogen bond interaction between curcumin and the starch matrix, thus, higher encapsulation efficiency. Finally, curcumin release studies showed that acetylated banana starch nanoparticles allowed more controlled release, probably due to their stronger hydrogen bond interaction with curcumin. Copyright © 2018. Published by Elsevier B.V.

Synthesis and characterization of rice starch laurate as food-grade emulsifier for canola oil-in-water emulsions.

PubMed

García-Tejeda, Y V; Leal-Castañeda, E J; Espinosa-Solis, V; Barrera-Figueroa, V

2018-08-15

The effect of esterification on hydrolyzed rice starch was analyzed, for this aim rice starch was hydrolyzed and subsequently esterified with lauroyl chloride at three modification levels. Starch derivatives were characterized regarding their degree of substitution (DS), water solubility index, z-potential, gelatinization, and digestibility properties. DS of derivatives of rice starch laurate ranged from 0.042 to 1.86. It was determined that after esterification the water solubility index increased from 3.44 to 53.61%, the z-potential decreased from -3.18 to -11.27, and the content of slowly digestible starch (SDS) decreased from 26.22 to 5.13%. Different emulsions with starch concentrations ranging from 6 to 30 wt% were evaluated. The most stable emulsions were those having 20 and 30 wt% of rice starch laurate. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preparation and characterization of starch-based loose-fill packaging foams

NASA Astrophysics Data System (ADS)

Fang, Qi

Regular and waxy corn starches were blended in various ratios with biodegradable polymers including polylactic acid (PLA), Eastar Bio Copolyester 14766 (EBC) and Mater-Bi ZF03U (MBI) and extruded with a C. W. Brabender laboratory twin screw extruder using a 3-mm die nozzle at 150°C and 150 rev/min. Physical characteristics including radial expansion, unit density and bulk density and water solubility index, water absorption characteristics, mechanical properties including compressibility, Young's modulus, spring index, bulk compressibility and bulk spring index and abrasion resistance were investigated as affected by the ingredient formulations, i.e. type of polymers, type of starches, polymer to starch ratio and starch moisture content. A completely randomized factorial blocking experimental design was used. Fifty-four treatments resulted. Each treatment was replicated three times. SAS statistical software package was used to analyze the data. Foams made of waxy starch had better radial expansion, lower unit density and bulk density than did foams made of regular starch. Regular starch foams had significantly lower water solubility index than did the waxy starch foams. PLA-starch foams had the lowest compressibility and Young's modulus. MBI-starch foams were the most rigid. All foams had excellent spring indices and bulk spring indices which were comparable to the spring index of commercial expanded polystyrene foam. Correlations were established between the foam mechanical properties and the physical characteristics. Foam compressibility and Young's modulus decreased as increases in radial expansion and decreases in unit and bulk densities. Their relationships were modeled with power law equations. No correlation was observed between spring index and bulk spring index and foam physical characteristics. MBI-starch foams had the highest equilibrium moisture content. EBC-starch and PLA-starch foams had similar water absorption characteristics. No significant difference existed in water absorption characteristics between foams made of regular and waxy starches. Empirical models were developed to correlate foam water absorption characteristics with relative humidity and polymer content. The developed models fit the data well with relatively small standard errors and uniformly scattered residual plots. Foams with higher polymer content had better abrasion resistance than did foams with lower polymer content.

Barley callus: a model system for bioengineering of starch in cereals.

PubMed

Carciofi, Massimiliano; Blennow, Andreas; Nielsen, Morten M; Holm, Preben B; Hebelstrup, Kim H

2012-09-07

Starch is the most important source of calories for human nutrition and the majority of it is produced by cereal farming. Starch is also used as a renewable raw material in a range of industrial sectors. It can be chemically modified to introduce new physicochemical properties. In this way starch is adapted to a variety of specific end-uses. Recombinant DNA technologies offers an alternative to starch industrial processing. The plant biosynthetic pathway can be manipulated to design starches with novel structure and improved technological properties. In the future this may reduce or eliminate the economical and environmental costs of industrial modification. Recently, many advances have been achieved to clarify the genetic mechanism that controls starch biosynthesis. Several genes involved in the synthesis and modification of complex carbohydrates in many organisms have been identified and cloned. This knowledge suggests a number of strategies and a series of candidate genes for genetic transformation of crops to generate new types of starch-based polymers. However transformation of cereals is a slow process and there is no easy model system available to test the efficiency of candidate genes in planta. We explored the possibility to use transgenic barley callus generated from immature embryo for a fast test of transgenic modification strategies of starch biosynthesis. We found that this callus contains 4% (w/w dw) starch granules, which we could modify by generating fully transgenic calli by Agrobacterium-transformation. A Green Fluorescent Protein reporter protein tag was used to identify and propagate only fully transgenic callus explants. Around 1 - 1.5 g dry weight of fully transgenic callus could be produced in 9 weeks. Callus starch granules were smaller than endosperm starch granules and contained less amylose. Similarly the expression profile of starch biosynthesis genes were slightly different in callus compared with developing endosperm. In this study we have developed an easy and rapid in planta model system for starch bioengineering in cereals. We suggest that this method can be used as a time-efficient model system for fast screening of candidate genes for the generation of modified starch or new types of carbohydrate polymers.

Barley callus: a model system for bioengineering of starch in cereals

PubMed Central

2012-01-01

Background Starch is the most important source of calories for human nutrition and the majority of it is produced by cereal farming. Starch is also used as a renewable raw material in a range of industrial sectors. It can be chemically modified to introduce new physicochemical properties. In this way starch is adapted to a variety of specific end-uses. Recombinant DNA technologies offers an alternative to starch industrial processing. The plant biosynthetic pathway can be manipulated to design starches with novel structure and improved technological properties. In the future this may reduce or eliminate the economical and environmental costs of industrial modification. Recently, many advances have been achieved to clarify the genetic mechanism that controls starch biosynthesis. Several genes involved in the synthesis and modification of complex carbohydrates in many organisms have been identified and cloned. This knowledge suggests a number of strategies and a series of candidate genes for genetic transformation of crops to generate new types of starch-based polymers. However transformation of cereals is a slow process and there is no easy model system available to test the efficiency of candidate genes in planta. Results We explored the possibility to use transgenic barley callus generated from immature embryo for a fast test of transgenic modification strategies of starch biosynthesis. We found that this callus contains 4% (w/w dw) starch granules, which we could modify by generating fully transgenic calli by Agrobacterium-transformation. A Green Fluorescent Protein reporter protein tag was used to identify and propagate only fully transgenic callus explants. Around 1 – 1.5 g dry weight of fully transgenic callus could be produced in 9 weeks. Callus starch granules were smaller than endosperm starch granules and contained less amylose. Similarly the expression profile of starch biosynthesis genes were slightly different in callus compared with developing endosperm. Conclusions In this study we have developed an easy and rapid in planta model system for starch bioengineering in cereals. We suggest that this method can be used as a time-efficient model system for fast screening of candidate genes for the generation of modified starch or new types of carbohydrate polymers. PMID:22958600

SNPs in genes functional in starch-sugar interconversion associate with natural variation of tuber starch and sugar content of potato (Solanum tuberosum L.).

PubMed

Schreiber, Lena; Nader-Nieto, Anna Camila; Schönhals, Elske Maria; Walkemeier, Birgit; Gebhardt, Christiane

2014-07-31

Starch accumulation and breakdown are vital processes in plant storage organs such as seeds, roots, and tubers. In tubers of potato (Solanum tuberosum L.) a small fraction of starch is converted into the reducing sugars glucose and fructose. Reducing sugars accumulate in response to cold temperatures. Even small quantities of reducing sugars affect negatively the quality of processed products such as chips and French fries. Tuber starch and sugar content are inversely correlated complex traits that are controlled by multiple genetic and environmental factors. Based on in silico annotation of the potato genome sequence, 123 loci are involved in starch-sugar interconversion, approximately half of which have been previously cloned and characterized. By means of candidate gene association mapping, we identified single-nucleotide polymorphisms (SNPs) in eight genes known to have key functions in starch-sugar interconversion, which were diagnostic for increased tuber starch and/or decreased sugar content and vice versa. Most positive or negative effects of SNPs on tuber-reducing sugar content were reproducible in two different collections of potato cultivars. The diagnostic SNP markers are useful for breeding applications. An allele of the plastidic starch phosphorylase PHO1a associated with increased tuber starch content was cloned as full-length cDNA and characterized. The PHO1a-HA allele has several amino acid changes, one of which is unique among all known starch/glycogen phosphorylases. This mutation might cause reduced enzyme activity due to impaired formation of the active dimers, thereby limiting starch breakdown. Copyright © 2014 Schreiber et al.

SNPs in Genes Functional in Starch-Sugar Interconversion Associate with Natural Variation of Tuber Starch and Sugar Content of Potato (Solanum tuberosum L.)

PubMed Central

Schreiber, Lena; Nader-Nieto, Anna Camila; Schönhals, Elske Maria; Walkemeier, Birgit; Gebhardt, Christiane

2014-01-01

Starch accumulation and breakdown are vital processes in plant storage organs such as seeds, roots, and tubers. In tubers of potato (Solanum tuberosum L.) a small fraction of starch is converted into the reducing sugars glucose and fructose. Reducing sugars accumulate in response to cold temperatures. Even small quantities of reducing sugars affect negatively the quality of processed products such as chips and French fries. Tuber starch and sugar content are inversely correlated complex traits that are controlled by multiple genetic and environmental factors. Based on in silico annotation of the potato genome sequence, 123 loci are involved in starch-sugar interconversion, approximately half of which have been previously cloned and characterized. By means of candidate gene association mapping, we identified single-nucleotide polymorphisms (SNPs) in eight genes known to have key functions in starch-sugar interconversion, which were diagnostic for increased tuber starch and/or decreased sugar content and vice versa. Most positive or negative effects of SNPs on tuber-reducing sugar content were reproducible in two different collections of potato cultivars. The diagnostic SNP markers are useful for breeding applications. An allele of the plastidic starch phosphorylase PHO1a associated with increased tuber starch content was cloned as full-length cDNA and characterized. The PHO1a-HA allele has several amino acid changes, one of which is unique among all known starch/glycogen phosphorylases. This mutation might cause reduced enzyme activity due to impaired formation of the active dimers, thereby limiting starch breakdown. PMID:25081979

Sensory and physicochemical evaluation of low-fat chicken mortadella with added native and modified starches.

PubMed

Prestes, R C; Silva, L B; Torri, A M P; Kubota, E H; Rosa, C S; Roman, S S; Kempka, A P; Demiate, I M

2015-07-01

The objective of this work was to evaluate the effect of adding different starches (native and modified) on the physicochemical, sensory, structural and microbiological characteristics of low-fat chicken mortadella. Two formulations containing native cassava and regular corn starch, coded CASS (5.0 % of cassava starch) and CORN (5.0 % of regular corn starch), and one formulation produced with physically treated starch coded as MOD1 (2.5 % of Novation 2300) and chemically modified starch coded as MOD2 (2.5 % of Thermtex) were studied. The following tests were performed: physicochemical characterization (moisture, ash, protein, starch and lipid contents, and water activity); cooling, freezing and reheating losses; texture (texture profile test); color coordinates (L*, a*, b*, C and h); microbiological evaluation; sensory evaluation (multiple comparison and preference test); and histological evaluation (light microscopy). There was no significant difference (p > 0.05) for ash, protein, cooling loss, cohesiveness or in the preference test for the tested samples. The other evaluated parameters showed significant differences (p < 0.05). Histological study allowed for a qualitative evaluation between the physical properties of the food and its microscopic structure. The best results were obtained for formulation MOD2 (2.5 % Thermtex). The addition of modified starch resulted in a better performance than the native starch in relation to the evaluated technological parameters, mainly in relation to reheating losses, which demonstrated the good interaction between the modified starch in the structure of the product and the possibility of the application of this type of starch in other types of functional meat products.

Contrasting effects of non-starch polysaccharide and resistant starch-based diets on the disposition and excretion of the food carcinogen, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), in a rat model.

PubMed

Ferguson, Lynnette R; Zhu, Shuotun; Kestell, Philip

2003-06-01

It has commonly been believed that increasing fibre in the diet should reduce the incidence of cancers, especially those of the colon and rectum. The earliest definitions of dietary fibre restricted the term to plant cell walls in which non-starch polysaccharides are key chemical components. However, new definitions encompass a wider range of materials, including starches resistant to digestion in the colon (resistant starches). Nevertheless, most definitions require that "dietary fibres" show physiological effects considered beneficial against cancer, including enhanced laxation and faecal bulking. On theoretical grounds, such properties might be expected to dilute the concentration of any carcinogen present and move it more rapidly through the colon, thereby reducing bioavailability. We have compared the properties of two dietary fibre preparations that are primarily non-starch polysaccharides with two resistant starch preparations for effects on carcinogen disposition in a rodent model. Although both preparations enhanced laxation and faecal bulking, only the non-starch polysaccharide preparation reduced carcinogen biovailability. Indeed, carcinogen biovailability was significantly enhanced by resistant starch. We suggest that there may be fundamental differences in the manner by which non-starch polysaccharides or resistant starches affect carcinogen disposition, and express concern that the events seen with the resistant starches [RS] are unlikely to be beneficial with respect to protection against cancer by exogenous carcinogens. Furthermore, the data reveal that the observation of enhanced laxation and faecal bulking does not necessarily imply a reduction in carcinogen bioavailability.

Starch-entrapped biopolymer microspheres as a novel approach to vary blood glucose profiles.

PubMed

Venkatachalam, Mahesh; Kushnick, Michael R; Zhang, Genyi; Hamaker, Bruce R

2009-10-01

With emerging knowledge of the impact of the metabolic quality of glycemic carbohydrates on human health, there is a need for novel carbohydrate ingredients that can be custom-made to deliver controlled amounts of glucose to the body and to test hypotheses on the postprandial metabolic consequences of carbohydrates. The goal of the present study was to demonstrate the applicability and action of starch-entrapped biopolymer microspheres as customized, novel, slowly digestible carbohydrates to obtain desired glycemic responses. Starch-entrapped microspheres were developed; and starch digestion and glucose release, subsequent to their cooking (100 degrees C, 20 min) in water, were initially monitored by measuring the rapidly digestible, slowly digestible, and resistant starch fractions using the in vitro Englyst assay. Glycemic and insulinemic responses after consumption of glucose and two different slowly digestible starch microsphere diets were compared using a crossover study in 10 healthy individuals. The mechanism of starch digestion in the microspheres was elucidated from scanning electron microscopic images of the in vitro digested microspheres. Factors such as biopolymer type and concentration, microsphere size, and starch type were manipulated to obtain starch materials with defined amounts of slowly digestible starch based on in vitro studies. Scanning electron microscopy showed that cooked starch entrapped in the dense biopolymer matrix is digested layer by layer from the outside to the inside of the microsphere. Glycemic and insulinemic responses to microsphere test diets were moderate as compared to a glucose diet, but more important, they showed extended glucose release. Starch-entrapped microspheres provide a useful tool to study the postprandial metabolic consequences of slowly digestible carbohydrates.

The effect of α- or β-casein addition to waxy maize starch on postprandial levels of glucose, insulin, and incretin hormones in pigs as a model for humans

PubMed Central

Kett, Anthony P.; Bruen, Christine M.; O'Halloran, Fiona; Chaurin, Valérie; Lawlor, Peadar G.; O'Mahony, James A.; Giblin, Linda; Fenelon, Mark A.

2012-01-01

Background Starch is a main source of glucose and energy in the human diet. The extent to which it is digested in the gastrointestinal tract plays a major role in variations in postprandial blood glucose levels. Interactions with other biopolymers, such as dairy proteins, during processing can influence both the duration and extent of this postprandial surge. Objective To evaluate the effect of the addition of bovine α- or β-casein to waxy maize starch on changes in postprandial blood glucose, insulin, and incretin hormones [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1)] in 30 kg pigs used as an animal model for humans. Design Gelatinised starch, starch gelatinised with α-casein, and starch gelatinised with β-casein were orally administered to trained pigs (n = 8) at a level of 60 g of available carbohydrate. Pre- and postprandial glucose measurements were taken every 15 min for the first hour and every 30 min thereafter up to 180 min. Insulin, GIP, and GLP-1 levels were measured in plasma samples up to 90 min postprandial. Results Starch gelatinised with α-casein had a significantly (p < 0.05) lower peak viscosity on pasting and resulted in significantly lower glucose release at 15, 30, and 90 min postprandial compared to starch gelatinised with β-casein. During the first 45-min postprandial, the area under the glucose curve (AUC) for starch gelatinised with α-casein was significantly (p < 0.05) lower than that for starch gelatinised with β-casein. There was also a significant (p < 0.05) difference at T30 in GIP levels in response to the control compared to starch gelatinised with α- or β-casein. Significant (p < 0.05) increases in several free amino acid concentrations were observed on ingestion of either α- or β-casein gelatinised with starch at 30 and 90 min postprandial compared to starch alone. In addition, plasma levels of six individual amino acids were increased on ingestion of starch gelatinised with α-casein compared to ingestion of starch gelatinised with β-casein. Conclusion The presence of casein fractions (α- or β-casein) in gelatinised waxy maize starch affects swelling characteristics, viscosity, and subsequent in vivo digestion as determined by glucose levels in blood postprandial. PMID:22509144

Overexpression of STARCH BRANCHING ENZYME II increases short-chain branching of amylopectin and alters the physicochemical properties of starch from potato tuber.

PubMed

Brummell, David A; Watson, Lyn M; Zhou, Jun; McKenzie, Marian J; Hallett, Ian C; Simmons, Lyall; Carpenter, Margaret; Timmerman-Vaughan, Gail M

2015-04-29

Starch is biosynthesised by a complex of enzymes including various starch synthases and starch branching and debranching enzymes, amongst others. The role of all these enzymes has been investigated using gene silencing or genetic knockouts, but there are few examples of overexpression due to the problems of either cloning large genomic fragments or the toxicity of functional cDNAs to bacteria during cloning. The aim of this study was to investigate the function of potato STARCH BRANCHING ENZYME II (SBEII) using overexpression in potato tubers. A hybrid SBEII intragene consisting of potato cDNA containing a fragment of potato genomic DNA that included a single intron was used in order to prevent bacterial translation during cloning. A population of 20 transgenic potato plants exhibiting SBEII overexpression was generated. Compared with wild-type, starch from these tubers possessed an increased degree of amylopectin branching, with more short chains of degree of polymerisation (DP) 6-12 and particularly of DP6. Transgenic lines expressing a GRANULE-BOUND STARCH SYNTHASE (GBSS) RNAi construct were also generated for comparison and exhibited post-transcriptional gene silencing of GBSS and reduced amylose content in the starch. Both transgenic modifications did not affect granule morphology but reduced starch peak viscosity. In starch from SBEII-overexpressing lines, the increased ratio of short to long amylopectin branches facilitated gelatinisation, which occurred at a reduced temperature (by up to 3°C) or lower urea concentration. In contrast, silencing of GBSS increased the gelatinisation temperature by 4°C, and starch required a higher urea concentration for gelatinisation. In lines with a range of SBEII overexpression, the magnitude of the increase in SBEII activity, reduction in onset of gelatinisation temperature and increase in starch swollen pellet volume were highly correlated, consistent with reports that starch swelling is greatly dependent upon the amylopectin branching pattern. This work reports the first time that overexpression of SBEII has been achieved in a non-cereal plant. The data show that overexpression of SBEII using a simple single-intron hybrid intragene is an effective way to modify potato starch physicochemical properties, and indicate that an increased ratio of short to long amylopectin branches produces commercially beneficial changes in starch properties such as reduced gelatinisation temperature, reduced viscosity and increased swelling volume.

OsbZIP58, a basic leucine zipper transcription factor, regulates starch biosynthesis in rice endosperm.

PubMed

Wang, Jie-Chen; Xu, Heng; Zhu, Ying; Liu, Qiao-Quan; Cai, Xiu-Ling

2013-08-01

Starch composition and the amount in endosperm, both of which contribute dramatically to seed yield, cooking quality, and taste in cereals, are determined by a series of complex biochemical reactions. However, the mechanism regulating starch biosynthesis in cereal seeds is not well understood. This study showed that OsbZIP58, a bZIP transcription factor, is a key transcriptional regulator controlling starch synthesis in rice endosperm. OsbZIP58 was expressed mainly in endosperm during active starch synthesis. osbzip58 null mutants displayed abnormal seed morphology with altered starch accumulation in the white belly region and decreased amounts of total starch and amylose. Moreover, osbzip58 had a higher proportion of short chains and a lower proportion of intermediate chains of amylopectin. Furthermore, OsbZIP58 was shown to bind directly to the promoters of six starch-synthesizing genes, OsAGPL3, Wx, OsSSIIa, SBE1, OsBEIIb, and ISA2, and to regulate their expression. These findings indicate that OsbZIP58 functions as a key regulator of starch synthesis in rice seeds and provide new insights into seed quality control.

Molecular order and functional properties of starches from three waxy wheat varieties grown in China.

PubMed

Wang, Shujun; Wang, Jinrong; Zhang, Wei; Li, Caili; Yu, Jinglin; Wang, Shuo

2015-08-15

Molecular order and functional properties of starch from three waxy wheat varieties grown in China were investigated by a combination of various technical analyses. The total starch content of the waxy wheat ranged between 54.1% and 55.0%, and the amylose content of the starch was between 0.71% and 1.63%. Average particle diameter of the three starches varied between 16.5 and 17.4 μm. Three waxy wheat starches presented the typical A-type X-ray diffraction pattern, with relative crystallinity between 38.7% and 40.0%. No significant differences were observed in relative crystallinity, IR ratios of 1047/1022 cm(-1) and 1022/995 cm(-1), and FWHH of the band at 480 cm(-1), indicating the similarity in long-range order of crystallites and short-range order of double helices of three starch granules. Small differences were observed in swelling power, gelatinization parameters, pasting viscosities, and in vitro enzymatic digestibility of three waxy wheat starches. Under the stored condition, no retrogradation occurred for three waxy wheat starches. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Yield of starch extraction from plantain (Musa paradisiaca). Pilot plant study].

PubMed

Flores-Gorosquera, Emigdia; García-Suárez, Francisco J; Flores-Huicochea, Emmanuel; Núñez-Santiago, María C; González-Soto, Rosalia A; Bello-Pérez, Luis A

2004-01-01

In México, the banana (Musa paradisiaca) is cooked (boiling or deep frying) before being eaten, but the consumption is not very popular and a big quantity of the product is lost after harvesting. The unripe plantain has a high level of starch and due to this the use of banana can be diversified as raw material for starch isolation. The objective of this work was to study the starch yield at pilot plant scale. Experiments at laboratory scale were carried out using the pulp with citric acid to 0,3 % (antioxidant), in order to evaluate the different unitary operations of the process. The starch yield, based on starch presence in the pulp that can be isolated, were between 76 and 86 %, and the values at pilot plant scale were between 63 and 71 %, in different lots of banana fruit. Starch yield values were similar among the diverse lots, showing that the process is reproducible. The lower values of starch recovery at pilot plant scale are due to the loss during sieving operations; however, the amount of starch recovery is good.

Measurement of resistant starch by enzymatic digestion in starch and selected plant materials: collaborative study.

PubMed

McCleary, Barry V; McNally, Marian; Rossiter, Patricia

2002-01-01

Interlaboratory performance statistics was determined for a method developed to measure the resistant starch (RS) content of selected plant food products and a range of commercial starch samples. Food materials examined contained RS (cooked kidney beans, green banana, and corn flakes) and commercial starches, most of which naturally contain, or were processed to yield, elevated RS levels. The method evaluated was optimized to yield RS values in agreement with those reported for in vivo studies. Thirty-seven laboratories tested 8 pairs of blind duplicate starch or plant material samples with RS values between 0.6 (regular maize starch) and 64% (fresh weight basis). For matrixes excluding regular maize starch, repeatability relative standard deviation (RSDr) values ranged from 1.97 to 4.2%, and reproducibility relative standard deviation (RSDR) values ranged from 4.58 to 10.9%. The range of applicability of the test is 2-64% RS. The method is not suitable for products with <1% RS (e.g., regular maize starch; 0.6% RS). For such products, RSDr and RSDR values are unacceptably high.

Effect of infrared and microwave radiations on properties of Indian Horse Chestnut starch.

PubMed

Shah, Umar; Gani, Adil; Ashwar, Bilal Ahmad; Shah, Asima; Wani, Idrees Ahmed; Masoodi, Farooq Ahmad

2016-03-01

Starch extracted from Indian Horse Chestnut (IHCN) was subjected to infrared and microwave radiations for different time intervals (15 s, 30 s, & 45 s) at constant dose. The structural change of MW and IR radiated IHCN starches were determined by Fourier transform-infra red spectroscopy. The increased peak intensity at 3240 cm(-1) of treated starch represents more exposure of hydroxyl groups due to radiation. Granule morphology of native starch showed round and elliptical granules with smooth surfaces. However radiation treatment resulted in the development of surface cracks. Effect of radiation on physicochemical properties of starch revealed increase in water absorption capacity and light transmittance and decrease in apparent amylose content, pH, and syneresis. The peak, trough, final, and setback viscosities were significantly reduced with increase in treatment time. Radiated starches displayed significantly lower values of To,Tp, and ΔHgel than native starch. Further antioxidant activities were evaluated by DPPH and FRAP assays. Results showed significant improvement in antioxidant activity of starch by both MW and IR treatments. Copyright © 2015 Elsevier B.V. All rights reserved.

Genetic dissection of floridean starch synthesis in the cytosol of the model dinoflagellate Crypthecodinium cohnii

PubMed Central

Dauvillée, David; Deschamps, Philippe; Ral, Jean-Philippe; Plancke, Charlotte; Putaux, Jean-Luc; Devassine, Jimi; Durand-Terrasson, Amandine; Devin, Aline; Ball, Steven G.

2009-01-01

Starch defines an insoluble semicrystalline form of storage polysaccharides restricted to Archaeplastida (red and green algae, land plants, and glaucophytes) and some secondary endosymbiosis derivatives of the latter. While green algae and land-plants store starch in plastids by using an ADP-glucose-based pathway related to that of cyanobacteria, red algae, glaucophytes, cryptophytes, dinoflagellates, and apicomplexa parasites store a similar type of polysaccharide named floridean starch in their cytosol or periplast. These organisms are suspected to store their floridean starch from UDP-glucose in a fashion similar to heterotrophic eukaryotes. However, experimental proof of this suspicion has never been produced. Dinoflagellates define an important group of both photoautotrophic and heterotrophic protists. We now report the selection and characterization of a low starch mutant of the heterotrophic dinoflagellate Crypthecodinium cohnii. We show that the sta1-1 mutation of C. cohnii leads to a modification of the UDP-glucose-specific soluble starch synthase activity that correlates with a decrease in starch content and an alteration of amylopectin structure. These experimental results validate the UDP-glucose-based pathway proposed for floridean starch synthesis. PMID:19940244

Iminosugar inhibitors of carbohydrate-active enzymes that underpin cereal grain germination and endosperm metabolism

PubMed Central

Andriotis, Vasilios M. E.; Rejzek, Martin; Rugen, Michael D.; Svensson, Birte; Smith, Alison M.; Field, Robert A.

2016-01-01

Starch is a major energy store in plants. It provides most of the calories in the human diet and, as a bulk commodity, it is used across broad industry sectors. Starch synthesis and degradation are not fully understood, owing to challenging biochemistry at the liquid/solid interface and relatively limited knowledge about the nature and control of starch degradation in plants. Increased societal and commercial demand for enhanced yield and quality in starch crops requires a better understanding of starch metabolism as a whole. Here we review recent advances in understanding the roles of carbohydrate-active enzymes in starch degradation in cereal grains through complementary chemical and molecular genetics. These approaches have allowed us to start dissecting aspects of starch degradation and the interplay with cell-wall polysaccharide hydrolysis during germination. With a view to improving and diversifying the properties and uses of cereal grains, it is possible that starch degradation may be amenable to manipulation through genetic or chemical intervention at the level of cell wall metabolism, rather than simply in the starch degradation pathway per se. PMID:26862201

Swelling and tensile properties of starch glycerol system with various crosslinking agents

NASA Astrophysics Data System (ADS)

Mohamed, R.; Mohd, N.; Nurazzi, N.; Siti Aisyah, M. I.; Fauzi, F. Mohd

2017-07-01

Brittle properties of starch had been overcome by the modification process. In this work, sago starch is being modified with variable amount of plasticiser, namely glycerol at 20 and 40% and crosslinking agent had been added to the system. The film of the modification and characterizations of the starch glycerol system with various crosslinking systems were produced by casting method. The film properties of the starch glycerol system were then characterized by tensile strength (mechanical properties) and swelling (physical properties). The modification of the starch glycerol had improved that system by increasing the tensile strength, modulus however lowering its elongation. The increasing in percentage of the water absorption and also swelling are due to the intrinsic hydroxyl groups presence from the starch and glycerol itself that can attract more water to the system. Upon crosslinking, films casted with chemicals namely, glyoxal, malonic acid, borax, PEG were characterised. It was found that, all the film of sago starch crosslinked and undergoing easy film formation. From this modification, borax and malonic acid crosslinking agent had been determined as the best crosslinking agent to the starch glycerol system.

Insights into the structural and physicochemical properties of small granular starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor.

PubMed

Chen, Lei; Yu, Changjiang; Ma, Yubin; Xu, Hua; Wang, Shumin; Wang, Yu; Liu, Xingxun; Zhou, Gongke

2016-11-29

The structure and physicochemical properties of starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor, were investigated and compared in this study. The amylose content and average size of starches were determined to be 20.85%, 4.70 μm and 27.77%, 6.17 μm for Spirodela oligorrhiza and Lemna minor, respectively. The average chain length of two duckweed starches was measured to be around DP 28. The chain length distribution was observed to be greatly different from other reported starches for the high proportion of long chains (DP ≥ 37) over 50%. Wide-angle X-ray diffraction profiles of the two starch samples displayed typical B-type diffraction pattern. The gelatinization enthalpy-changes (ΔH gel ) of two starch samples was about 10.40 J/g for two duckweed starches. The present results suggested the potential utilization of small granular starches from duckweed in functional foods and dietary supplement products. Copyright © 2016 Elsevier Ltd. All rights reserved.

A comparative study of sodium dodecyl sulfate and freezing/thawing treatment on wheat starch: The role of water absorption.

PubMed

Tao, Han; Wang, Pei; Zhang, Bao; Wu, Fengfeng; Jin, Zhengyu; Xu, Xueming

2016-06-05

The effect of freezing on functionality of native and sodium dodecyl sulfate (SDS)-treated wheat starches was investigated, with the aim of understanding the role of water absorption during freezing process. SDS is one of most efficient detergents to remove non-starch components (such as proteins and lipids) for starches but does not cause any apparent damage on granular structure. Slow swelling could be converted to rapid swelling by SDS washing, indicating higher water absorption. Freezing process induced slight roughness on starch granules but the non-starch components content was little affected. Combined SDS+freezing treatment significantly decreased both amylose and proteins non-starch components contents, which was accompanied with high gelatinization temperatures, melting enthalpy, and pasting viscosities. A smaller bread specific volume was obtained from SDS+freezing-treated starches while the crumb firmness significantly increased (p<0.05). SDS mainly extracted the surface components from starch granules, leading to high water absorption and making granules sensitive to the freezing treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Starch Applications for Delivery Systems

NASA Astrophysics Data System (ADS)

Li, Jason

2013-03-01

Starch is one of the most abundant and economical renewable biopolymers in nature. Starch molecules are high molecular weight polymers of D-glucose linked by α-(1,4) and α-(1,6) glycosidic bonds, forming linear (amylose) and branched (amylopectin) structures. Octenyl succinic anhydride modified starches (OSA-starch) are designed by carefully choosing a proper starch source, path and degree of modification. This enables emulsion and micro-encapsulation delivery systems for oil based flavors, micronutrients, fragrance, and pharmaceutical actives. A large percentage of flavors are encapsulated by spray drying in today's industry due to its high throughput. However, spray drying encapsulation faces constant challenges with retention of volatile compounds, oxidation of sensitive compound, and manufacturing yield. Specialty OSA-starches were developed suitable for the complex dynamics in spray drying and to provide high encapsulation efficiency and high microcapsule quality. The OSA starch surface activity, low viscosity and film forming capability contribute to high volatile retention and low active oxidation. OSA starches exhibit superior performance, especially in high solids and high oil load encapsulations compared with other hydrocolloids. The submission is based on research and development of Ingredion

A comparative analysis of green synthesis approach starch capped metal oxides (ZnO & CdO) nanoparticles and its bacterial activity

NASA Astrophysics Data System (ADS)

Vidhya, K.; Devarajan, V. P.; Viswanathan, C.; Nataraj, D.; Bhoopathi, G.

2013-06-01

In this study, we have investigated the bacterial activity of starch capped ZnO & CdO NPs. The NPs were prepared through green technique under room temperature and then obtained samples were characterized by using XRD and PL techniques. XRD pattern confirms the crystal nature it shows hexagonal structure for ZnO NPs and monoclinic structure for CdO NPs and their average particle size is ±20 nm. Further, the optical properties of NPs were investigated using PL technique in which the starch capped ZnO NPs shows maximum emission at 440 nm whereas starch capped CdO NPs shows maximum emission at 545 nm. Finally, toxic test was performed with E.coli bacteria and their results were investigated. Hence, starch capped ZnO NPs induced less killing effect when compared with starch capped CdO NPs. Therefore, we conclude that the starch capped ZnO NPs may be less toxic to microorganisms when compared with starch capped CdO NPs. In addition, starch capped ZnO NPs is also suitable for anti-microbial activity.

Humidity-activated shape memory effect on plasticized starch-based biomaterials.

PubMed

Sessini, Valentina; Arrieta, Marina P; Fernández-Torres, Alberto; Peponi, Laura

2018-01-01

Humidity-activated shape memory behavior of plasticized starch-based films reinforced with the innovative combination of starch nanocrystals (SNCs) and catechin as antioxidant were studied. In a previous work, we reported the processing of gelatinized starch-based films filled with SNCs and catechin as antioxidant agent, and we observed that this novel combination leads to starch-based film with enhanced thermal and mechanical performance. In this work, the humidity-activated shape memory behavior of the previous developed starch-based films was characterized. The moisture loss as well as the moisture absorption were studied since they are essential parameters in humidity-activated shape memory polymers to fix the temporary shape and to recover the original shape, respectively. Therefore, the effect of the incorporation of SNCs and catechin on the humidity-activated shape memory properties of plasticized starch was also studied. Moreover, the effectiveness of catechin to increase the polymer stability under oxidative atmosphere and the thermo-mechanical relaxation of all the starch-based materials were studied. The combination of plasticized starch matrix loaded with both, SNCs and catechin, leads to a multifunctional starch-based films with increased hydrophilicity and with excellent humidity-activated shape memory behavior with interest for potential biomedical applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Milling of rice grains: effects of starch/flour structures on gelatinization and pasting properties.

PubMed

Hasjim, Jovin; Li, Enpeng; Dhital, Sushil

2013-01-30

Starch gelatinization and flour pasting properties were determined and correlated with four different levels of starch structures in rice flour, i.e. flour particle size, degree of damaged starch granules, whole molecular size, and molecular branching structure. Onset starch-gelatinization temperatures were not significantly different among all flour samples, but peak and conclusion starch-gelatinization temperatures were significantly different and were strongly correlated with the flour particle size, indicating that rice flour with larger particle size has a greater barrier for heat transfer. There were slight differences in the enthalpy of starch gelatinization, which are likely associated with the disruption of crystalline structure in starch granules by the milling processes. Flours with volume-median diameter ≥56 μm did not show a defined peak viscosity in the RVA viscogram, possibly due to the presence of native protein and/or cell-wall structure stabilizing the swollen starch granules against the rupture caused by shear during heating. Furthermore, RVA final viscosity of flour was strongly correlated with the degree of damage to starch granules, suggesting the contribution of granular structure, possibly in swollen form. The results from this study allow the improvement in the manufacture and the selection criteria of rice flour with desirable gelatinization and pasting properties. Copyright © 2012 Elsevier Ltd. All rights reserved.

Morphological and physicochemical characterization of porous starches obtained from different botanical sources and amylolytic enzymes.

PubMed

Benavent-Gil, Yaiza; Rosell, Cristina M

2017-10-01

Porous starches might offer an attractive alternative as bio-adsorbents of a variety of compounds. However, morphology and physicochemical properties of starches must be understood before exploring their applications. Objective was to study the action of different amylolytic enzymes for producing porous starches. Wheat, rice, potato and cassava starches were treated with Amyloglucosidase (AMG), α-amylase (AM) and cyclodextrin-glycosyltransferase (CGTase). Morphological characteristics, chemical composition, adsorptive capacity and pasting/thermal properties were assessed. Scanning Electron Microscopy (SEM) showed porous structures with diverse pore size distribution, which was dependent on the enzyme type and starch source, but no differences were observed in the total granule surface occupied by pores. The adsorptive capacity analysis revealed that modified starches had high water absorptive capacity and showed different oil adsorptive capacity depending on the enzyme type. Amylose content analysis revealed different hydrolysis pattern of the amylases, suggesting that AMG mainly affected crystalline region meanwhile AM and CGTase attacked amorphous area. A heatmap illustrated the diverse pasting properties of the different porous starches, which also showed significant different thermal properties, with different behavior between cereal and tuber starches. Therefore, it is possible to modulate the properties of starches through the use of different enzymes. Copyright © 2017 Elsevier B.V. All rights reserved.

Cecropia peltata Accumulates Starch or Soluble Glycogen by Differentially Regulating Starch Biosynthetic Genes[W][OA

PubMed Central

Bischof, Sylvain; Umhang, Martin; Eicke, Simona; Streb, Sebastian; Qi, Weihong; Zeeman, Samuel C.

2013-01-01

The branched glucans glycogen and starch are the most widespread storage carbohydrates in living organisms. The production of semicrystalline starch granules in plants is more complex than that of small, soluble glycogen particles in microbes and animals. However, the factors determining whether glycogen or starch is formed are not fully understood. The tropical tree Cecropia peltata is a rare example of an organism able to make either polymer type. Electron micrographs and quantitative measurements show that glycogen accumulates to very high levels in specialized myrmecophytic structures (Müllerian bodies), whereas starch accumulates in leaves. Compared with polymers comprising leaf starch, glycogen is more highly branched and has shorter branches—factors that prevent crystallization and explain its solubility. RNA sequencing and quantitative shotgun proteomics reveal that isoforms of all three classes of glucan biosynthetic enzyme (starch/glycogen synthases, branching enzymes, and debranching enzymes) are differentially expressed in Müllerian bodies and leaves, providing a system-wide view of the quantitative programming of storage carbohydrate metabolism. This work will prompt targeted analysis in model organisms and cross-species comparisons. Finally, as starch is the major carbohydrate used for food and industrial applications worldwide, these data provide a basis for manipulating starch biosynthesis in crops to synthesize tailor-made polyglucans. PMID:23632447

Isolation and characterization of starch from industrial fresh pasta by-product and its potential use in sugar-snap cookie making.

PubMed

Ellouzi, Soumaya Zouari; Driss, Dorra; Maktouf, Sameh; Neifar, Mohamed; Kobbi, Ameni; Kamoun, Hounaida; Chaabouni, Semia Ellouze; Ghorbel, Raoudha Ellouze

2015-09-01

In this paper, starch was extracted from fresh pasta by-product (PS) and its chemical composition and physical and microscopic characteristics were determined. Commercial wheat starch (CS) was used as reference. In general, purity was similar between starches studied. However, others compounds such as protein, lipid and ash were significantly different. PS starch granules had large lenticular-shape (25-33 μm) and small spherical-shape (5-8 μm). The pH and color of PS starch were similar to those reported for CS starch. On the other hand, PS had higher water absorption capacity, viscosity and cooking stability than CS. The gelatinization temperature of PS was similar to that of CS (60 and 61 °C). At high temperature (90 °C) both starches had similar rheological behavior. The results achieved suggest that PS starch has potential for application in food systems requiring high processing temperatures such the manufacture of sugar snap cookie. The effects of PS starch addition on the dough making stage and the final cookie quality were analyzed. Improvements in dough cohesiveness (24 %) and springiness (10 %) were significant relative to those of CS dough. Texture profile analysis confirmed the rheological changes.

Effects of adding corn oil and soy protein to corn starch on the physicochemical and digestive properties of the starch.

PubMed

Chen, Xu; He, Xiao-Wei; Zhang, Bin; Fu, Xiong; Jane, Jay-Lin; Huang, Qiang

2017-11-01

This study aimed to understand effects of adding corn oil (CO) and soy protein (SP) to corn starch on the physicochemical properties and digestive rates of annealed starch complex and mechanisms of interactions between corn starch (CS), CO and SP. Binary and ternary blends were prepared using CS mixed with CO (10%, dsb) and/or SP (10%, dsb) and incubated in a water bath at 50°C for 14h. Results showed that more agglomerates of the granules were in the ternary blends. With the addition of CO and/or SP, the CS displayed a decreased pasting temperature, an increased peak viscosity and a decreased enthalpy change of amylose-lipid complex dissociation. The CO can reinforce but SP hinder the annealing phenomenon. Results also showed that CO decreased retrogradation of CS, whereas SP increased it. The digestibility studies showed that the addition of CO and SP decreased the content of rapidly digestible starch and increased the sum of slowly digestible starch and resistant starch contents. SP displayed more impact on the digestibility of the ternary blends than CO. The physical barrier of CO, and amylose-lipid complex and protein-starch matrix can provide resistance to starch digestion. Copyright © 2017. Published by Elsevier B.V.

Morphological, mechanical, barrier and properties of films based on acetylated starch and cellulose from barley.

PubMed

El Halal, Shanise Lisie Mello; Colussi, Rosana; Biduski, Bárbara; Evangelho, Jarine Amaral do; Bruni, Graziella Pinheiro; Antunes, Mariana Dias; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2017-01-01

Biodegradable films of native or acetylated starches with different concentrations of cellulose fibers (0%, 10% and 20%) were prepared. The films were characterized by morphological, mechanical, barrier, and thermal properties. The tensile strength of the acetylated starch film was lower than those of the native starch film, without fibers. The addition of fibers increased the tensile strength and decreased the elongation and the moisture of native and acetylated starches films. The acetylated starch film showed higher water solubility when compared to native starch film. The addition of cellulose fibers reduced the water solubility of the acetylated starch film. The films reinforced with cellulose fiber exhibited a higher initial decomposition temperature and thermal stability. The mechanical, barrier, solubility, and thermal properties are factors which direct the type of the film application in packaging for food products. The films elaborated with acetylated starches of low degree of substitution were not effective in a reduction of the water vapor permeability. The addition of the cellulose fiber in acetylated and native starches films can contribute to the development of more resistant films to be applied in food systems that need to maintain their integrity. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Improving biomass and starch accumulation of bioenergy crop duckweed (Landoltia punctata) by abscisic acid application.

PubMed

Liu, Yang; Chen, Xiaoyi; Wang, Xinhui; Fang, Yang; Huang, Mengjun; Guo, Ling; Zhang, Yin; Zhao, Hai

2018-06-22

Duckweed is a valuable feedstock for bioethanol production due to its high biomass and starch accumulation. In our preliminary experiment, we found that abscisic acid (ABA) could simultaneously increase starch and biomass accumulation of duckweed, but the mechanisms are still unclear. The results showed that the biomass production of duckweed reached up to 59.70 and 63.93 g m -2 in 6 days, respectively, with an increase of 7% (P < 0.05) compared to the control. The starch percentage increased from 2.29% up to 46.18% after 14 days of treatment, with a total of starch level 2.6-fold higher than that of the control. Moreover, the level of endogenous ABA, zeatin-riboside (ZR) and indole-3-acetic acid (IAA) increased, while gibberellins (GAs) decreased. Notably, ABA content in treated samples reached 336.5 mg/kg (fresh weight), which was 7.5-fold greater than that of the control. Importantly, the enzyme activities involved in starch biosynthesis increased while those catalyzing starch degradation decreased after ABA application. Taken together, these results indicated that ABA can promote biomass and starch accumulation by regulating endogenous hormone levels and the activity of starch metabolism related key enzymes. These results will provide an operable method for high starch accumulation in duckweed for biofuels production.

Starch-Branching Enzyme IIa Is Required for Proper Diurnal Cycling of Starch in Leaves of Maize1[OA

PubMed Central

Yandeau-Nelson, Marna D.; Laurens, Lieve; Shi, Zi; Xia, Huan; Smith, Alison M.; Guiltinan, Mark J.

2011-01-01

Starch-branching enzyme (SBE), a glucosyl transferase, is required for the highly regular pattern of α-1,6 bonds in the amylopectin component of starch. In the absence of SBEIIa, as shown previously in the sbe2a mutant of maize (Zea mays), leaf starch has drastically reduced branching and the leaves exhibit a severe senescence-like phenotype. Detailed characterization of the maize sbe2a mutant revealed that SBEIIa is the primary active branching enzyme in the leaf and that in its absence plant growth is affected. Both seedling and mature sbe2a mutant leaves do not properly degrade starch during the night, resulting in hyperaccumulation. In mature sbe2a leaves, starch hyperaccumulation is greatest in visibly senescing regions but also observed in green tissue and is correlated to a drastic reduction in photosynthesis within the leaf. Starch granules from sbe2a leaves observed via scanning electron microscopy and transmission electron microscopy analyses are larger, irregular, and amorphous as compared with the highly regular, discoid starch granules observed in wild-type leaves. This appears to trigger premature senescence, as shown by an increased expression of genes encoding proteins known to be involved in senescence and programmed cell death processes. Together, these results indicate that SBEIIa is required for the proper diurnal cycling of transitory starch within the leaf and suggest that SBEIIa is necessary in producing an amylopectin structure amenable to degradation by starch metabolism enzymes. PMID:21508184

Starch bioengineering affects cereal grain germination and seedling establishment

PubMed Central

Hebelstrup, Kim H.; Blennow, Andreas

2014-01-01

Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule structure, and not only the endosperm starch content per se, is important for germination and seedling establishment. For that purpose, wild-type (WT), and specifically engineered degradable hyperphosphorylated (HP) starch and more resistant amylose-only (AO) starch barley lines were used. The transgenics showed no severe phenotypes and the WT and HP lines degraded the starch similarly, having 30% residual starch after 12 d of germination. However, the AO line showed significant resistance to degradation, having 57% residual starch. Interestingly, protein and β-glucan (BG) degradation was stimulated for both HP and AO lines as compared with the WT. At late seedling establishment stages, specific sugars were rapidly consumed in the AO line. α-Amylase activity was distinctly suppressed in both the HP and the AO lines. Pre-germination β-amylase deposition was low in the AO grains and β-amylase was generally suppressed in both HP and AO lines throughout germination. As further supported by scanning electron microscopy and histochemical analyses on grain and seedlings, it was concluded that inadequate starch granule deposition in combination with the suppressed hydrolase activity leads to temporal and compensating re-direction of starch, sugar, and protein catabolism important to maintain metabolic dynamics during grain germination and seedling establishment. PMID:24642850

Engineering starch accumulation by manipulation of phosphate metabolism of starch.

PubMed

Weise, Sean E; Aung, Kimberly; Jarou, Zach J; Mehrshahi, Payam; Li, Ziru; Hardy, Anna C; Carr, David J; Sharkey, Thomas D

2012-06-01

A new understanding of leaf starch degradation has emerged in the last 10 years. It has been shown that starch phosphorylation and dephosphorylation are critical components of this process. Glucan, water dikinase (GWD) (and phosphoglucan, water dikinase) adds phosphate to starch, and phosphoglucan phosphatase (SEX4) removes these phosphates. To explore the use of this metabolism to manipulate starch accumulation, Arabidopsis (Arabidopsis thaliana) plants were engineered by introducing RNAi constructs designed to reduce expression of AtGWD and AtSEX4. The timing of starch build-up was altered with ethanol-inducible and senescence-induced gene promoters. Ethanol induction of RNAi lines reduced transcript for AtGWD and AtSEX4 by 50%. The transgenic lines had seven times more starch than wild type at the end of the dark period but similar growth rates and total biomass. Elevated leaf starch content in maize leaves was engineered by making an RNAi construct against a gene in maize that appeared to be homologous to AtGWD. The RNAi construct was expressed using the constitutive ubiquitin promoter. Leaf starch content at the end of a night period in engineered maize plants was 20-fold higher than in untransformed plants with no impact on total plant biomass. We conclude that plants can be engineered to accumulate starch in the leaves with little impact on vegetative biomass. © 2012 The Authors. Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Functional and structural characterization of plastidic starch phosphorylase during barley endosperm development

PubMed Central

Ruzanski, Christian; Krucewicz, Katarzyna; Meier, Sebastian; Hägglund, Per; Svensson, Birte; Palcic, Monica M.

2017-01-01

The production of starch is essential for human nutrition and represents a major metabolic flux in the biosphere. The biosynthesis of starch in storage organs like barley endosperm operates via two main pathways using different substrates: starch synthases use ADP-glucose to produce amylose and amylopectin, the two major components of starch, whereas starch phosphorylase (Pho1) uses glucose-1-phosphate (G1P), a precursor for ADP-glucose production, to produce α-1,4 glucans. The significance of the Pho1 pathway in starch biosynthesis has remained unclear. To elucidate the importance of barley Pho1 (HvPho1) for starch biosynthesis in barley endosperm, we analyzed HvPho1 protein production and enzyme activity levels throughout barley endosperm development and characterized structure-function relationships of HvPho1. The molecular mechanisms underlying the initiation of starch granule biosynthesis, that is, the enzymes and substrates involved in the initial transition from simple sugars to polysaccharides, remain unclear. We found that HvPho1 is present as an active protein at the onset of barley endosperm development. Notably, purified recombinant protein can catalyze the de novo production of α-1,4-glucans using HvPho1 from G1P as the sole substrate. The structural properties of HvPho1 provide insights into the low affinity of HvPho1 for large polysaccharides like starch or amylopectin. Our results suggest that HvPho1 may play a role during the initiation of starch biosynthesis in barley. PMID:28407006

Classification of cassava starch films by physicochemical properties and water vapor permeability quantification by FTIR and PLS.

PubMed

Henrique, C M; Teófilo, R F; Sabino, L; Ferreira, M M C; Cereda, M P

2007-05-01

Cassava starches are widely used in the production of biodegradable films, but their resistance to humidity migration is very low. In this work, commercial cassava starch films were studied and classified according to their physicochemical properties. A nondestructive method for water vapor permeability determination, which combines with infrared spectroscopy and multivariate calibration, is also presented. The following commercial cassava starches were studied: pregelatinized (amidomax 3550), carboxymethylated starch (CMA) of low and high viscosities, and esterified starches. To make the films, 2 different starch concentrations were evaluated, consisting of water suspensions with 3% and 5% starch. The filmogenic solutions were dried and characterized for their thickness, grammage, water vapor permeability, water activity, tensile strength (deformation force), water solubility, and puncture strength (deformation). The minimum thicknesses were 0.5 to 0.6 mm in pregelatinized starch films. The results were treated by means of the following chemometric methods: principal component analysis (PCA) and partial least squares (PLS) regression. PCA analysis on the physicochemical properties of the films showed that the differences in concentration of the dried material (3% and 5% starch) and also in the type of starch modification were mainly related to the following properties: permeability, solubility, and thickness. IR spectra collected in the region of 4000 to 600 cm(-1) were used to build a PLS model with good predictive power for water vapor permeability determination, with mean relative errors of 10.0% for cross-validation and 7.8% for the prediction set.

Assessment of the mobile bag method for estimation of in vivo starch digestibility.

PubMed

Ghoorchi, T; Lund, P; Larsen, M; Hvelplund, T; Hansen-Møller, J; Weisbjerg, M R

2013-02-01

The objective was to assess the ability of the in situ mobile nylon bag method for predicting small intestinal and total tract starch digestibility. Starch disappearance was measured for 18 samples of different cereals and legumes subjected to different physical and chemical processing methods and compared with coherent in vivo digestibility. Starch disappearance was measured both with and without initial ruminal pre-incubation during 4 h. Bags were retrieved from either the ileal cannula or faeces. Two dry Danish Holstein cows fitted with rumen cannulas were used for rumen pre-incubations and two lactating Danish Holstein cows fitted with duodenal and ileal cannulas were used for intestinal incubations. Rumen pre-incubation had no significant effect on disappearance from bags recovered in faeces. The disappearance of legume starch was lower, both in the rumen and small intestine, compared with starch from barley, wheat, oats, ear maize and maize. Transit times of the mobile bags from duodenum to ileum were not significantly different between feeds. A weak positive correlation was found between in vivo small intestinal and total tract digestibility of starch and disappearance obtained using the mobile bag technique across a broad range of starch sources. Omitting two less conventional starch sources (NaOH wheat and xylose-treated barley) resulted in a high (0.87) correlation between total tract in vivo digestibility and mobile bag disappearance. The use of the mobile bag method for estimation of in vivo starch digestibility will therefore depend on the starch type.

Second Harmonic Generation Mediated by Aligned Water in Starch Granules.

PubMed

Cisek, Richard; Tokarz, Danielle; Krouglov, Serguei; Steup, Martin; Emes, Michael J; Tetlow, Ian J; Barzda, Virginijus

2014-12-26

The origin of second harmonic generation (SHG) in starch granules was investigated using ab initio quantum mechanical modeling and experimentally examined using polarization-in, polarization-out (PIPO) second harmonic generation microscopy. Ab initio calculations revealed that the largest contribution to the SHG signal from A- and B-type allomorphs of starch originates from the anisotropic organization of hydroxide and hydrogen bonds mediated by aligned water found in the polymers. The hypothesis was experimentally tested by imaging maize starch granules under various hydration and heat treatment conditions that alter the hydrogen bond network. The highest SHG intensity was found in fully hydrated starch granules, and heat treatment diminished the SHG intensity. The PIPO SHG imaging showed that dried starch granules have a much higher nonlinear optical susceptibility component ratio than fully hydrated granules. In contrast, deuterated starch granules showed a smaller susceptibility component ratio demonstrating that SHG is highly sensitive to the organization of the hydroxyl and hydrogen bond network. The polarization SHG imaging results of potato starch granules, representing starch allomorph B, were compared to those of maize starch granules representing allomorph A. The results showed that the amount of aligned water was higher in the maize granules. Nonlinear microscopy of starch granules provides evidence that varying hydration conditions leads to significant changes in the nonlinear susceptibility ratio as well as the SHG intensity, supporting the hypothesis from ab initio calculations that the dominant contribution to SHG is due to the ordered hydroxide and hydrogen bond network.

Starch as a feedstock for bioproducts and packaging

USDA-ARS?s Scientific Manuscript database

Much progress has been achieved in developing starch-based feedstocks as a partial replacement for petroleum-based feedstocks. Although starch remains a poor direct substitute for plastics, composite starch-based materials have useful functional properties and are in commercial production as a repla...

7 CFR 4288.102 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... biomass, other than corn kernel starch, to include: (1) Biofuel derived from cellulose, hemicellulose, or lignin; (2) Biofuel derived from sugar and starch (other than ethanol derived from corn kernel starch... kernel starch. Eligible renewable energy content. That portion of an advanced biofuel's energy content...

7 CFR 4288.102 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... biomass, other than corn kernel starch, to include: (1) Biofuel derived from cellulose, hemicellulose, or lignin; (2) Biofuel derived from sugar and starch (other than ethanol derived from corn kernel starch... kernel starch. Eligible renewable energy content. That portion of an advanced biofuel's energy content...

7 CFR 4288.102 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... biomass, other than corn kernel starch, to include: (1) Biofuel derived from cellulose, hemicellulose, or lignin; (2) Biofuel derived from sugar and starch (other than ethanol derived from corn kernel starch... kernel starch. Eligible renewable energy content. That portion of an advanced biofuel's energy content...

Fractionation and reconstitution experiments provide insight into the role of starch gelatinization and pasting properties in pasta quality.

PubMed

Delcour, J A; Vansteelandt, J; Hythier, M; Abécassis, J

2000-09-01

Commercial durum wheat semolina was fractionated into protein, starch, water-extractable, and sludge fractions. The starch fraction was hydroxypropylated, annealed, or cross-linked to change its gelatinization and pasting properties. Spaghettis were made by reconstitution of the fractions, and their quality was assessed. Hydroxypropylated starches were detrimental for cooked pasta quality. Cross-linked starches made the reconstituted pasta firmer and even brittle when the degree of cross-linking was too high. These results indicate that starch properties play a role in pasta quality, although the gluten remains very important as an ultrastructure agent. It was concluded that, given a certain gluten ultrastructure, starch water uptake and gel properties and/or its interference with or breakdown of the continuous gluten network during cooking determine pasta quality.

Optical characterization of CdS nanorods capped with starch

NASA Astrophysics Data System (ADS)

Roy, J. S.; Pal Majumder, T.; Schick, C.

2015-05-01

Well crystalline uniform CdS nanorods were grown by changing the concentration of maize starch. The highly polymeric (branched) structure of starch enhances the growth of CdS nanorods. The average diameter of the nanorods is 20-25 nm while length is of 500-600 nm as verified from SEM and XRD observations. The optical band gaps of the CdS nanorods are varying from 2.66 eV to 2.52 eV depending on concentration of maize starch. The photoluminescence (PL) emission bands are shifted from 526 nm to 529 nm with concentration of maize starch. We have also observed the enhanced PL intensity in CdS nanorods capped with starch. The Fourier transform infrared (FTIR) spectroscopy shows the significant effect of starch on CdS nanorods.

Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits

PubMed Central

Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

2016-01-01

Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develop commercial cassava varieties with amylose-free starch. However, little information is available regarding the biological and agronomic implications of starch mutations in cassava, nor in other root and tuber crops. In this study, siblings from eight full-sib families, segregating for the waxy trait, were used to determine if the mutation has implications for yield, dry matter content (DMC) and harvest index in cassava. A total of 87 waxy and 87 wild-type starch genotypes from the eight families were used in the study. The only significant effect of starch type was on DMC (p < 0.01), with waxy clones having a 0.8% lower content than their wild type counterparts. There was no effect of starch type on fresh root yield (FRY), adjusted FRY and harvest index. It is not clear if lower DMC is a pleiotropic effect of the waxy starch mutation or else the result of linked genes introgressed along with the mutation. It is expected that commercial waxy cassava varieties will have competitive FRYs but special efforts will be required to attain adequate DMCs. This study contributes to the limited knowledge available of the impact of starch mutations on the agronomic performance of root and tuber crops. PMID:27242813

The role of two isoenzymes of alpha-amylase of Araucaria araucana (Araucariaceae) on the digestion of starch granules during germination.

PubMed

Waghorn, Juana J; del Pozo, Talía; Acevedo, Elba A; Cardemil, Liliana A

2003-03-01

Starch is the principal reserve of Araucaria araucana seeds, and it is hydrolysed during germination mainly by alpha-amylase. There are several alpha-amylase isoenzymes whose patterns change in the embryo and in the megagametophyte from the one observed in quiescent seeds (T(0)) to a different one observed 90 h after imbibition (T(90)). The objective of this research was to study the roles of two purified alpha-amylase isoenzymes by in vitro digestion of starch granules extracted from the tissues at two times of imbibition: one is abundant in quiescent seeds and the other is abundant after 90 h of imbibition. The isoenzymes digested the starch granules of their own stage of germination better, since the isoenzyme T(0) digested starch granules mainly from quiescent seeds, while the isoenzyme T(90) digested starch mainly at 90 h of imbibition. The sizes of the starch granule and the tissue from which these granules originated make a difference to digestion by the isoenzymes. Embryonic isoenzyme T(0) digested large embryonic starch granules better than small and medium-sized granules, and better than those isolated from megagametophytes. Similarly isoenzyme T(90) digested small embryonic starch granules better than medium-sized and large granules, and better than those isolated from megagametophytes. However, a mixture of partially purified megagametophytic isoenzymes T(0) and T(90) digested the megagametophytic granules better than those isolated from embryos. Studies of in vitro sequential digestion of starch granules with these isoenzymes corroborated their specificity. The isoenzyme T(90) digested starch granules previously digested by the isoenzyme T(0). This suggests that in vivo these two isoenzymes may act sequentially in starch granule digestion.

The deposition and characterization of starch in Brachypodium distachyon

PubMed Central

Tanackovic, Vanja; Svensson, Jan T.; Jensen, Susanne L.; Buléon, Alain; Blennow, Andreas

2014-01-01

Brachypodium distachyon is a non-domesticated cereal. Nonetheless, Brachypodium was recently introduced as a model plant for temperate cereals. This study compares grain starch metabolism in Brachypodium and barley (Hordeum vulgare). In Brachypodium, we identified and annotated 28 genes involved in starch metabolism and identified important motifs including transit peptides and putative carbohydrate-binding modules (CBMs) of the families CBM20, CBM45, CBM48, and CBM53. Starch content was markedly lower in Brachypodium grains (12%) compared to barley grains (47%). Brachypodium starch granules were doughnut shaped and bimodally distributed into distinct small B-type (2.5–10 µm) and very small C-type (0.5–2.5 µm) granules. Large A-type granules, typical of cereals, were absent. Starch-bound phosphate, important for starch degradation, was 2-fold lower in Brachypodium compared with barley indicating different requirements for starch mobilization. The amylopectin branch profiles were similar and the amylose content was only slightly higher compared with barley cv. Golden Promise. The crystallinity of Brachypodium starch granules was low (10%) compared to barley (20%) as determined by wide-angle X-ray scattering (WAXS) and molecular disorder was confirmed by differential scanning calorimetry (DSC). The expression profiles in grain for most genes were distinctly different for Brachypodium compared to barley, typically showing earlier decline during the course of development, which can explain the low starch content and differences in starch molecular structure and granule characteristics. High transitory starch levels were observed in leaves of Brachypodium (2.8% after 14h of light) compared to barley (1.9% after 14h of light). The data suggest important pre-domesticated features of cereals. PMID:25056772

Small intestinal digestion of raw cornstarch in cattle consuming a soybean hull-based diet is improved by duodenal casein infusion.

PubMed

Brake, D W; Titgemeyer, E C; Bailey, E A; Anderson, D E

2014-09-01

Six duodenally and ileally cannulated steers were used in 3 sequential studies to measure 1) basal nutrient flows from a soybean hull-based diet, 2) small intestinal digestibility of raw cornstarch continuously infused into the duodenum, and 3) responses of small intestinal starch digestion to duodenal infusion of 200 or 400 g/d casein. Our objective was to evaluate responses in small intestinal starch digestion in cattle over time and to measure responses in small intestinal starch digestion to increasing amounts of MP. On average, cattle consumed 3.7 kg/d DM, 68 g/d dietary N, and 70 g/d dietary starch. Starch flow to the duodenum was small (38 g/d), and N flow was 91 g/d. Small intestinal digestibility of duodenal N was 57%, and small intestinal digestion of duodenal starch flow was extensive (92%). Small intestinal starch digestibility was 34% when 1.5 kg/d raw cornstarch was continuously infused into the duodenum. Subsequently, cattle were placed in 1 of 2 replicated Latin squares that were balanced for carryover effects to determine response to casein infusions and time required for adaptation. Duodenal infusion of casein linearly increased (P ≤ 0.05) small intestinal starch digestibility, and small intestinal starch digestion adapted to infusion of casein in 6 d. Ethanol-soluble starch and unpolymerized glucose flowing to the ileum increased linearly (P ≤ 0.05) with increasing infusion of casein. Plasma cholecystokinin was not affected by casein infusion, but circulating levels of glucose were increased by casein supplementation (P ≤ 0.05). Responses in small intestinal starch digestion in cattle adapted to casein within 6 d, and increases in duodenal supply of casein up to 400 g/d increased small intestinal starch digestion in cattle.

In vivo phosphoproteome characterization reveals key starch granule-binding phosphoproteins involved in wheat water-deficit response.

PubMed

Chen, Guan-Xing; Zhen, Shou-Min; Liu, Yan-Lin; Yan, Xing; Zhang, Ming; Yan, Yue-Ming

2017-10-23

Drought stress during grain development causes significant yield loss in cereal production. The phosphorylated modification of starch granule-binding proteins (SGBPs) is an important mechanism regulating wheat starch biosynthesis. In this study, we performed the first proteomics and phosphoproteomics analyses of SGBPs in elite Chinese bread wheat (Triticum aestivum L.) cultivar Jingdong 17 under well-watered and water-stress conditions. Water stress treatment caused significant reductions in spike grain numbers and weight, total starch and amylopectin content, and grain yield. Two-dimensional gel electrophoresis revealed that the quantity of SGBPs was reduced significantly by water-deficit treatment. Phosphoproteome characterization of SGBPs under water-deficit treatment demonstrated a reduced level of phosphorylation of main starch synthesis enzymes, particularly for granule-bound starch synthase (GBSS I), starch synthase II-a (SS II-a), and starch synthase III (SS III). Specifically, the Ser34 site of the GBSSI protein, the Tyr358 site of SS II-a, and the Ser837 site of SS III-a exhibited significant less phosphorylation under water-deficit treatment than well-watered treatment. Furthermore, the expression levels of several key genes related with starch biosynthesis detected by qRT-PCR were decreased significantly at 15 days post-anthesis under water-deficit treatment. Immunolocalization showed a clear movement of GBSS I from the periphery to the interior of starch granules during grain development, under both water-deficit and well-watered conditions. Our results demonstrated that the reduction in gene expression or transcription level, protein expression and phosphorylation levels of starch biosynthesis related enzymes under water-deficit conditions is responsible for the significant decrease in total starch content and grain yield.

Starch-related alpha-glucan/water dikinase is involved in the cold-induced development of freezing tolerance in Arabidopsis.

PubMed

Yano, Ryoichi; Nakamura, Masanobu; Yoneyama, Tadakatsu; Nishida, Ikuo

2005-06-01

Cold-induced soluble sugar accumulation enhances the degree of freezing tolerance in various cold-hardy plants including Arabidopsis (Arabidopsis thaliana), where soluble sugars accumulate in only a few hours at 2 degrees C. Hence, along with photosynthesis, starch degradation might play a significant role in cold-induced sugar accumulation and enhanced freezing tolerance. Starch-related alpha-glucan/water dikinase (EC 2.7.9.4), encoded by Arabidopsis STARCH EXCESS 1 (SEX1), is hypothesized to regulate starch degradation in plastids by phosphorylating starch, thereby ensuring better accessibility by starch-degrading enzymes. Here, we show that Arabidopsis sex1 mutants, when incubated at 2 degrees C for 1 d, were unable to accumulate maltooligosaccharides or normal glucose and fructose levels. In addition, they displayed impaired freezing tolerance. After 7 d at 2 degrees C, sex1 mutants did not show any of the above abnormal phenotypes but displayed slightly higher leaf starch contents. The impaired freezing tolerance of sex1 mutants was restored by overexpression of wild-type SEX1 cDNA using the cauliflower mosaic virus 35S promoter. The results demonstrate a genetic link between the SEX1 locus and plant freezing tolerance, and show that starch degradation is important for enhanced freezing tolerance during an early phase of cold acclimation. However, induction of starch degradation was not accompanied by significant changes in alpha-glucan/water dikinase activity in leaf extracts and preceded cold-induced augmentation of SEX1 transcripts. Therefore, we conclude that augmentation of SEX1 transcripts might be a homeostatic response to low temperature, and that starch degradation during an early phase of cold acclimation could be regulated by a component(s) of a starch degradation pathway(s) downstream of SEX1.

Individual Differences in AMY1 Gene Copy Number, Salivary α-Amylase Levels, and the Perception of Oral Starch

PubMed Central

Mandel, Abigail L.; Peyrot des Gachons, Catherine; Plank, Kimberly L.; Alarcon, Suzanne; Breslin, Paul A. S.

2010-01-01

Background The digestion of dietary starch in humans is initiated by salivary α-amylase, an endo-enzyme that hydrolyzes starch into maltose, maltotriose and larger oligosaccharides. Salivary amylase accounts for 40 to 50% of protein in human saliva and rapidly alters the physical properties of starch. Importantly, the quantity and enzymatic activity of salivary amylase show significant individual variation. However, linking variation in salivary amylase levels with the oral perception of starch has proven difficult. Furthermore, the relationship between copy number variations (CNVs) in the AMY1 gene, which influence salivary amylase levels, and starch viscosity perception has not been explored. Principal Findings Here we demonstrate that saliva containing high levels of amylase has sufficient activity to rapidly hydrolyze a viscous starch solution in vitro. Furthermore, we show with time-intensity ratings, which track the digestion of starch during oral manipulation, that individuals with high amylase levels report faster and more significant decreases in perceived starch viscosity than people with low salivary amylase levels. Finally, we demonstrate that AMY1 CNVs predict an individual's amount and activity of salivary amylase and thereby, ultimately determine their perceived rate of oral starch viscosity thinning. Conclusions By linking genetic variation and its consequent salivary enzymatic differences to the perceptual sequellae of these variations, we show that AMY1 copy number relates to salivary amylase concentration and enzymatic activity level, which, in turn, account for individual variation in the oral perception of starch viscosity. The profound individual differences in salivary amylase levels and salivary activity may contribute significantly to individual differences in dietary starch intake and, consequently, to overall nutritional status. PMID:20967220

Simultaneous silencing of isoamylases ISA1, ISA2 and ISA3 by multi-target RNAi in potato tubers leads to decreased starch content and an early sprouting phenotype

PubMed Central

Ferreira, Stephanus J.; Senning, Melanie; Fischer-Stettler, Michaela; Streb, Sebastian; Ast, Michelle; Neuhaus, H. Ekkehard; Zeeman, Samuel C.; Sonnewald, Sophia

2017-01-01

Isoamylases hydrolyse (1–6)-alpha-D-glucosidic linkages in starch and are involved in both starch granule formation and starch degradation. In plants, three isoamylase isoforms with distinct functions in starch synthesis (ISA1 and ISA2) and degradation (ISA3) have been described. Here, we created transgenic potato plants with simultaneously decreased expression of all three isoamylases using a chimeric RNAi construct targeting all three isoforms. Constitutive expression of the hairpin RNA using the 35S CaMV promoter resulted in efficient silencing of all three isoforms in leaves, growing tubers, and sprouting tubers. Neither plant growth nor tuber yield was effected in isoamylase-deficient potato lines. Interestingly, starch metabolism was found to be impaired in a tissue-specific manner. While leaf starch content was unaffected, tuber starch was significantly reduced. The reduction in tuber starch content in the transgenic plants was accompanied by a decrease in starch granules size, an increased sucrose content and decreased hexose levels. Despite the effects on granule size, only little changes in chain length composition of soluble and insoluble glucose polymers were detected. The transgenic tubers displayed an early sprouting phenotype that was accompanied by an increased level of sucrose in parenchyma cells below the outgrowing bud. Since high sucrose levels promote sprouting, we propose that the increased number of small starch granules may cause an accelerated turnover of glucan chains and hence a more rapid synthesis of sucrose. This observation links alterations in starch structure/degradation with developmental processes like meristem activation and sprout outgrowth in potato tubers. PMID:28708852

Effects of starch synthase IIa gene dosage on grain, protein and starch in endosperm of wheat.

PubMed

Konik-Rose, Christine; Thistleton, Jenny; Chanvrier, Helene; Tan, Ihwa; Halley, Peter; Gidley, Michael; Kosar-Hashemi, Behjat; Wang, Hong; Larroque, Oscar; Ikea, Joseph; McMaugh, Steve; Regina, Ahmed; Rahman, Sadequr; Morell, Matthew; Li, Zhongyi

2007-11-01

Starch synthases (SS) are responsible for elongating the alpha-1,4 glucan chains of starch. A doubled haploid population was generated by crossing a line of wheat, which lacks functional ssIIa genes on each genome (abd), and an Australian wheat cultivar, Sunco, with wild type ssIIa alleles on each genome (ABD). Evidence has been presented previously indicating that the SGP-1 (starch granule protein-1) proteins present in the starch granule in wheat are products of the ssIIa genes. Analysis of 100 progeny lines demonstrated co-segregation of the ssIIa alleles from the three genomes with the SGP-1 proteins, providing further evidence that the SGP-1 proteins are the products of the ssIIa genes. From the progeny lines, 40 doubled haploid lines representing the eight possible genotypes for SSIIa (ABD, aBD, AbD, ABd, abD, aBd, Abd, abd) were characterized for their grain weight, protein content, total starch content and starch properties. For some properties (chain length distribution, pasting properties, swelling power, and gelatinization properties), a progressive change was observed across the four classes of genotypes (wild type, single nulls, double nulls and triple nulls). However, for other grain properties (seed weight and protein content) and starch properties (total starch content, granule morphology and crystallinity, granule size distribution, amylose content, amylose-lipid dissociation properties), a statistically significant change only occurred for the triple nulls, indicating that all three genes had to be missing or inactive for a change to occur. These results illustrate the importance of SSIIa in controlling grain and starch properties and the importance of amylopectin fine structure in controlling starch granule properties in wheat.

[Resistant starches. Part II. Physico-chemical and technological aspects solution medico-biological problems].

PubMed

Iur'ev, V P; Gapparov, M M; Vasserman, L A; Genkina, N K

2006-01-01

This paper is a review of the recent literature data related to structure, composition and physico-chemical properties of starches as well as the special methods of processing of the starch containing raw sources producing the food products with increasing content of resistant starches. The prognosis is made about usefulness of such resistant starches for control of some metabolic disorder in human organism and for prophylactic aims.

Effects of plantain and corn starches on the mechanical and disintegration properties of paracetamol tablets.

PubMed

Akin-Ajani, Olufunke D; Itiola, Oludele A; Odeku, Oluwatoyin A

2005-10-22

The effects of plantain starch obtained from the unripe fruit of the plant Musa paradisiaca L. (Musaceae) on the mechanical and disintegration properties of paracetamol tablets have been investigated in comparison with the effects of corn starch BP using a 2(3) factorial experimental design. The individual and combined effects of nature of starch binder (N), concentration of starch binder (C), and the relative density of tablet (RD) on the tensile strength (TS), brittle fracture index (BFI), and disintegration time (DT) of the tablets were investigated. The ranking of the individual effects on TS was RD > C > N, on BFI was C > RD > N and on DT was N > C > RD. The ranking for the interaction effects on TS and DT was N-C > N-RD > C-RD, while that on BFI was N-C > C-RD > N-RD. Changing nature of starch from a "low" (plantain starch) to a "high" (corn starch) level, increasing the concentration of starch binding agent from 2.5% to 10.0% wt/wt, and increasing relative density of the tablet from 0.80 to 0.90, led to increase in the values of TS and DT, but a decrease in BFI. Thus, tablets containing plantain starch had lower tensile strength and disintegration time values than those containing corn starch, but showed better ability to reduce the lamination and capping tendency in paracetamol tablet formulation. The interaction between N and C was significantly (P < .001) higher than those between N and RD and between C and RD. There is therefore the need to carefully choose the nature (N) and concentration (C) of starch used as binding agent in tablet formulations to obtain tablets of desired bond strength and disintegration properties. Furthermore, plantain starch could be useful as an alternative binding agent to cornstarch, especially where faster disintegration is required and the problems of lamination and capping are of particular concern.

Re-Evaluation of the Role of Starch in Gravitropic Sensing

NASA Technical Reports Server (NTRS)

Sack, Fred D.

1998-01-01

Plant organs grow toward or away from gravity as a way to orient those organs for optimizing growth. Starch has long been thought to be important in sensing the direction of the g-vector in gravitropism, but that hypothesis has also evoked controversy. We have previously shown that starch-deficient mutants of Arabidopsis (TC7) and Nicotiana (NS458) are impaired in their gravitropism. While this suggests that starch is not necessary for reduced gravitropism, it also indicates that the mass of the starch contributes to sensing when present and thus is necessary for full gravitropic sensitivity. The research supported by this grant focused on three related projects, (1) the effect of light on hypocotyl gravitropism in NS458, (2) the effects of root phototropism on measurements of gravitropic sensitivity, and (3) the effects of starch overproduction on sedimentation and gravitropism. Collectively, our results provide additional strong support for the importance of starch in gravitropic sensing. First, by accounting for negative phototropism in roots of two starchless mutants of Arabidopsis we have established that these mutants are much less sensitive to gravity than previously thought. This work also demonstrates the importance of designing experimental protocols that remove the influence of root phototropism on measuring root gravitropism. Second, light apparently promotes gravitropism in starch-deficient Nicotiana hypocotyls by increasing the trace amounts of starch in the plastids, by inducing limited plastid sedimentation and thus by presumably increasing the signal provided by plastid mass. And finally, we show that excess starch in Arabidopsis seedlings has little effect on gravitropic sensitivity implying that the sensing system is already saturated. However, in light-grown stems where this mutation results in starch accumulation and where the wild-type practically lacks starch in the sensing cells, the mutant is much more sensitive than the wild-type again showing that the loss of starch depresses gravity sensing.

Mapping and comparative proteomic analysis of the starch biosynthetic pathway in rice by 2D PAGE/MS.

PubMed

Chang, Tao-Shan; Liu, Chih-Wei; Lin, Yu-Ling; Li, Chao-Yi; Wang, Arthur Z; Chien, Min-Wei; Wang, Chang-Sheng; Lai, Chien-Chen

2017-11-01

Our results not only provide a comprehensive overview of the starch biosynthetic pathway in the developing endosperm but also reveal some important protein markers that regulate the synthesis of starch. In human diets, rice (Oryza sativa L.) is an important source of starch, a substantial amount of which is accumulated in developing endosperm. A better understanding of the complicated pathways involved in starch biosynthesis is needed to improve the yield and quality of rice and other cereal crops through breeding. One pure line rice mutant, SA0419, was induced from a wild-type rice, TNG67, by sodium azide mutagenesis; therefore, TNG67 and SA0419 share the same genetic background. SA0419 is, however, a unique glutinous rice with a lower amylose content (8%) than that of TNG67 (20%), and the grains of SA0419 develop earlier and faster than those of TNG67. In this study, we used a comparative proteomic analysis to identify the differentially expressed proteins that may explain the differences in starch biosynthesis and the characteristics of TNG67 and SA0419. A gel-based proteomic approach was applied to profile the expressed proteome in the developing endosperm of these two rice varieties by nano-LC/MS/MS. Several over-expressed proteins were found in SA0419, such as plastidial ADP-glucose pyrophosphorylase (AGPase), phosphoglucomutase (PGM), pyrophosphate-fructose 6-phosphate 1-phosphotransferase (PFP), 6-phosphofructokinase (PFK), pyruvate phosphate dikinase (PPDK), starch branching enzymes (SBE) and starch debranching enzyme (SDBE), with those proteins mainly being involved in the pathways of starch metabolism and PPDK-mediated gluconeogenesis. Those over-expressed enzymes may contribute to the relatively early development, similar starch accumulation and rapid grain filling of SA0419 as compared with TNG67. This study provides a detailed biochemical description of starch biosynthesis and related information regarding a unique starch mutant that may assist future research efforts to improve the yield and quality of grain and starch in rice through breeding.

Esterification of Starch in Ionic Liquids

USDA-ARS?s Scientific Manuscript database

We shall discuss the use of various ionic liquids in the preparation of starch esters. Starch was reacted with vinyl acetate in different 1-butyl-3-methylimidazolium (bmim) salts as solvents in an effort to produce starches with different acetylation patterns. Overall degree of substitution (DS) w...

Starch-based Foam Composite Materials: processing and bioproducts

USDA-ARS?s Scientific Manuscript database

Starch is an abundant, biodegradable, renewable and low-cost commodity that has been explored as a replacement for petroleum-based plastics. By itself, starch is a poor replacement for plastics because of its moisture sensitivity and brittle properties. Efforts to improve starch properties and funct...

Recent processing methods for preparing starch-based bioproducts

USDA-ARS?s Scientific Manuscript database

There is currently an intense interest in starch-based materials because of the low cost of starch, the replacement of dwindling petroleum-based resources with annually-renewable feedstocks, the biodegradability of starch-based products, and the creation of new markets for farm commodities. Non-trad...

Agro-industrial residue from starch extraction of Pachyrhizus ahipa as filler of thermoplastic corn starch films.

PubMed

López, O V; Versino, F; Villar, M A; García, M A

2015-12-10

Biocomposites films based on thermoplastic corn starch (TPS) containing 0.5% w/w fibrous residue from Pachyrhizus ahipa starch extraction (PASR) were obtained by melt-mixing and compression molding. PASR is mainly constituted by remaining cell walls and natural fibers, revealed by Scanning Electron Microscopy (SEM). Chemical composition of the residue indicated that fiber and starch were the principal components. Biocomposites thermo-stability was determined by Thermo-Gravimetric Analysis. A continuous PASR-TPS interface was observed by SEM, as a result of a good adhesion of the fibrous residue to starch matrix. Likewise, films containing PASR presented fewer superficial cracks than TPS ones, whereas their fracture surfaces were more irregular. Besides, the presence of PASR increased starch films roughness, due to fibers agglomerates. Films reinforced with PASR showed significantly lower water vapor permeability (WVP). In addition, PARS filler increased maximum tensile strength and Young's modulus of TPS films, thus leading to more resistant starch matrixes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synchrotron X-ray Scattering Analysis of the Interaction Between Corn Starch and an Exogenous Lipid During Hydrothermal Treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

E Hernandez-Hernandez; C Avila-Orta; B Hsiao

Lipids have an important effect on starch physicochemical properties. There exist few reports about the effect of exogenous lipids on native corn starch structural properties. In this work, a study of the morphological, structural and thermal properties of native corn starch with L-alpha-lysophosphatidylcholine (LPC, the main phospholipid in corn) was performed under an excess of water. Synchrotron radiation, in the form of real-time small and wide-angle X-ray scattering (SAXS/WAXS), was used in order to track structural changes in corn starch, in the presence of LPC during a heating process from 30 to 85 C. When adding LCP, water absorption decreasedmore » within starch granule amorphous regions during gelatinization. This is explained by crystallization of the amylose-LPC inclusion complex during gelatinization, which promotes starch granule thermal stability at up to 95 C. Finally, a conceptual model is proposed for explaining the formation mechanism of the starch-LPC complex.« less

Understanding how the aggregation structure of starch affects its gastrointestinal digestion rate and extent.

PubMed

Chen, Pei; Wang, Kai; Kuang, Qirong; Zhou, Sumei; Wang, Dazheng; Liu, Xingxun

2016-06-01

Regulating the starch gastrointestinal digestion rate by control of its aggregation structure is an effective way, but the mechanism is still not clear. Multi-scale structure of waxy and normal wheat starches were studied by confocal laser scanning and scanning electron microscopes, as well as wide-angle and small-angle X-ray techniques in this study. In vitro digestion kinetics of those two starches and structure-digestion relationship were also discussed. Both waxy and normal starches show A-type diffraction pattern, but waxy variety shows a slightly higher crystallinity. Small-angle X-ray scattering results show that waxy wheat starch has higher scattering peak intensity (Imax) and a larger crystallinity lamellar repeat distance (Lp) compared with the normal wheat starch. We suggested that the higher digestion rate of waxy starch at initial stage is mainly due to more small-size particles, but the higher crystallinity and the larger crystalline lamellar size limit the digestion extent. Copyright © 2016 Elsevier B.V. All rights reserved.

Calcium modified edible Canna (Canna edulis L) starch for controlled released matrix

NASA Astrophysics Data System (ADS)

Putri, A. P.; Ridwan, M.; Darmawan, T. A.; Darusman, F.; Gadri, A.

2017-07-01

Canna edulis L starch was modified with calcium chloride in order to form controlled released matrix. Present study aim to analyze modified starch characteristic. Four different formulation of ondansetron granules was used to provide dissolution profile of controlled released, two formula consisted of 15% and 30% modified starch, one formula utilized matrix reference standards and the last granules was negative control. Methocel-hydroxypropyl methyl cellulose was used as controlled released matrix reference standards in the third formula. Calcium starch was synthesized in the presence of sodium hydroxide to form gelatinized mass and calcium chloride as the cross linking agent. Physicochemical and dissolution properties of modified starch for controlled released application were investigated. Modified starch has higher swelling index, water solubility and compressibility index. Three of four different formulation of granules provide dissolution profile of controlled released. The profiles indicate granules which employed calcium Canna edulis L starch as matrix are able to resemble controlled drug released profile of matrix reference, however their bigger detain ability lead to lower bioavailability.

Black leaf streak disease affects starch metabolism in banana fruit.

PubMed

Saraiva, Lorenzo de Amorim; Castelan, Florence Polegato; Shitakubo, Renata; Hassimotto, Neuza Mariko Aymoto; Purgatto, Eduardo; Chillet, Marc; Cordenunsi, Beatriz Rosana

2013-06-12

Black leaf streak disease (BLSD), also known as black sigatoka, represents the main foliar disease in Brazilian banana plantations. In addition to photosynthetic leaf area losses and yield losses, this disease causes an alteration in the pre- and postharvest behavior of the fruit. The aim of this work was to investigate the starch metabolism of fruits during fruit ripening from plants infected with BLSD by evaluating carbohydrate content (i.e., starch, soluble sugars, oligosaccharides, amylose), phenolic compound content, phytohormones, enzymatic activities (i.e., starch phosphorylases, α- and β-amylase), and starch granules. The results indicated that the starch metabolism in banana fruit ripening is affected by BLSD infection. Fruit from infested plots contained unusual amounts of soluble sugars in the green stage and smaller starch granules and showed a different pattern of superficial degradation. Enzymatic activities linked to starch degradation were also altered by the disease. Moreover, the levels of indole-acetic acid and phenolic compounds indicated an advanced fruit physiological age for fruits from infested plots.

Horse chestnut (Aesculus hippocastanum L.) starch: Basic physico-chemical characteristics and use as thermoplastic material.

PubMed

Castaño, J; Rodríguez-Llamazares, S; Contreras, K; Carrasco, C; Pozo, C; Bouza, R; Franco, C M L; Giraldo, D

2014-11-04

Starch isolated from non-edible Aesculus hippocastanum seeds was characterized and used for preparing starch-based materials. The apparent amylose content of the isolated starch was 33.1%. The size of starch granules ranged from 0.7 to 35 μm, and correlated with the shape of granules (spherical, oval and irregular). The chain length distribution profile of amylopectin showed two peaks, at polymerization degree (DP) of 12 and 41-43. Around 53% of branch unit chains had DP in the range of 11-20. A. hippocastanum starch displayed a typical C-type pattern and the maximum decomposition temperature was 317 °C. Thermoplastic starch (TPS) prepared from A. hippocastanum with glycerol and processed by melt blending exhibited adequate mechanical and thermal properties. In contrast, plasticized TPS with glycerol:malic acid (1:1) showed lower thermal stability and a pasty and sticky behavior, indicating that malic acid accelerates degradation of starch during processing. Copyright © 2014 Elsevier Ltd. All rights reserved.

In Vitro Starch Digestibility of Commercial Gluten-Free Pasta: The Role of Ingredients and Origin.

PubMed

Marti, Alessandra; Abbasi Parizad, Parisa; Marengo, Mauro; Erba, Daniela; Pagani, Maria Ambrogina; Casiraghi, Maria Cristina

2017-04-01

Gluten replacement in gluten-free (GF) products presents major challenges for the food industry in terms of sensorial, technological and nutritional characteristics. The absence of gluten reportedly affects starch digestibility, thus increasing the postprandial glycaemic response. However, the role of ingredients and processing conditions has been addressed only seldom. We investigated the in vitro starch digestibility of 9 commercial GF products (5 Italian pasta and 4 Oriental noodles) differing in formulation and processing conditions. Content of rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) were assessed and combined with information on starch pasting properties and on the overall protein organization. Oriental noodles presented higher relative levels of RS and RDS than Western-style pasta, that often had SDS levels compatible with low rates of starch digestion. As regard formulation, presence of multiple ingredients seems to likely increase the RDS level, as did the different protein organization in the various samples. © 2017 Institute of Food Technologists®.

Preparation and characterization of dialdehyde starch by one-step acid hydrolysis and oxidation.

PubMed

Zuo, Yingfeng; Liu, Wenjie; Xiao, Junhua; Zhao, Xing; Zhu, Ying; Wu, Yiqiang

2017-10-01

Dialdehyde starch was prepared by one-step synthesis of acid hydrolysis and oxidation, using corn starch as the raw material, sodium periodate (NaIO 4 ) as the oxidant, and hydrochloric acid (HCl) as the acid solution. The prepared dialdehyde starch was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and gel permeation chromatography (GPC). The results confirmed that oxidation occurred between the starch and NaIO 4 . The acid hydrolysis reaction reduced the molecular weight of starch and effectively improved the aldehyde group contents (92.7%). Scanning electron microscope (SEM) analysis indicated that the average particle size decreased after acid hydrolysis and oxidation reaction. X-ray diffraction (XRD) and thermal gravimetric analyzer (TGA) analysis demonstrated that the crystallinity of the obtained dialdehyde starch showed a downward trend and a decelerated thermal decomposition rate. The starch after acid hydrolysis and oxidation exhibited lower hot paste viscosity and higher reactivity. Copyright © 2017. Published by Elsevier B.V.

Hydration-induced crystalline transformation of starch polymer under ambient conditions.

PubMed

Qiao, Dongling; Zhang, Binjia; Huang, Jing; Xie, Fengwei; Wang, David K; Jiang, Fatang; Zhao, Siming; Zhu, Jie

2017-10-01

With synchrotron small/wide-angle X-ray scattering (SAXS/WAXS), we revealed that post-harvest hydration at ambient conditions can further alter the starch crystalline structure. The hydration process induced the alignment of starch helices into crystalline lamellae, irrespective of the starch type (A- or B-). In this process, non-crystalline helices were probably packed with water molecules to form new crystal units, thereby enhancing the overall concentration of starch crystallinity. In particular, a fraction of the monoclinic crystal units of the A-type starches encapsulated water molecules during hydration, leading to the outward movement of starch helices. Such movement resulted in the transformation of monoclinic units into hexagonal units, which was associated with the B-type crystallites. Hence, the hydration under ambient conditions could enhance the B-polymorphic features for both A-type and B-type starches. The new knowledge obtained here may guide the design of biopolymer-based liquid crystal materials with controlled lattice regularity and demanded features. Copyright © 2017 Elsevier B.V. All rights reserved.

Isolation and partial characterization of starch from banana cultivars grown in Colombia.

PubMed

Chávez-Salazar, A; Bello-Pérez, L A; Agama-Acevedo, E; Castellanos-Galeano, F J; Álvarez-Barreto, C I; Pacheco-Vargas, G

2017-05-01

Banana starch is resistant to hydrolysis by digestive enzymes due to its structure and dietary fibre content. Starch was isolated from the following three cultivars of Colombian Musaceae: Gros Michel (dessert), Dominico Harton and FHIA 20 (cooking); also, the amylose and amylopectin contents, morphology of the granules, thermal properties, pasting, molecular characteristics and digestibility were determined. The total starch content, amylose content and digestibility (gelatinized starch) were higher in cooking varieties; the purity and gelatinization temperature were similar for the three varieties, but the enthalpy was higher in the dessert variety. The three varieties showed higher viscosities in the pasting profile compared to commercial maize starch in both acid and neutral conditions. Starch granules presented with heterogeneous sizes and shapes (elongated and ovals) that had birefringence. The Dominico Hartón variety showed the lowest rapidly digestible starch (RDS) value in the gelatinized sample that is in agreement with the greater proportion of long chains. Copyright © 2017 Elsevier B.V. All rights reserved.

Microstructural characteristics and gastro-small intestinal digestion in vitro of potato starch: Effects of refrigerated storage and reheating in microwave.

PubMed

Colussi, Rosana; Singh, Jaspreet; Kaur, Lovedeep; Zavareze, Elessandra da Rosa; Dias, Alvaro Renato Guerra; Stewart, Robert B; Singh, Harjinder

2017-07-01

The objective of our study was to evaluate paste clarity, retrogradation (syneresis %), thermal characteristics and kinetics of glucose release during in vitro gastro-small intestinal digestion of freshly cooked and refrigerated potato starch. Freshly cooked starch pastes had a paste clarity of 71%, which decreased to 35.4% whereas syneresis (%) increased after 7days of refrigerated storage. The X-ray and thermal characteristics of native, retrograded and microwave reheated starch samples differed significantly from each other. For the freshly cooked starch pastes, ∼88% starch hydrolysis was observed at the end (150min) of digestion under simulated gastro-small intestinal conditions that decreased to ∼70% for the 7day stored pastes. The hydrolysis (%) of refrigerated pastes increased to 86% and 92% after one and two cycles of microwave reheating, respectively. These results contribute to the understanding of starch retrogradation in relation to starch digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of high hydrostatic pressure and retrogradation treatments on structural and physicochemical properties of waxy wheat starch.

PubMed

Hu, Xiao-Pei; Zhang, Bao; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

2017-10-01

In this study, the effects of high hydrostatic pressure and retrogradation (HHPR) treatments on in vitro digestibility, structural and physicochemical properties of waxy wheat starch were investigated. The waxy wheat starch slurries (10%, w/v) were treated with high hydrostatic pressures of 300, 400, 500, 600MPa at 20°C for 30min, respectively, and then retrograded at 4°C for 4d. The results indicated that the content of slowly digestible starch (SDS) in HHPR-treated starch samples increased with increasing pressure level, and it reached the maximum (31.12%) at 600MPa. HHPR treatment decreased the gelatinization temperatures, the gelatinization enthalpy, the relative crystallinity and the peak viscosity of the starch samples. Moreover, HHPR treatment destroyed the surface and interior structures of starch granules. These results suggest that the in vitro digestibility, physicochemical, and structural properties of waxy wheat starch are effectively modified by HHPR. Copyright © 2017 Elsevier Ltd. All rights reserved.

Extraction and characterization of arrowroot (Maranta arundinaceae L.) starch and its application in edible films.

PubMed

Nogueira, Gislaine Ferreira; Fakhouri, Farayde Matta; de Oliveira, Rafael Augustus

2018-04-15

This research work aimed extraction and characterization of arrowroot starch. Besides, the effects of different concentrations of starch (2.59-5.41%, mass/mass) and concentrations of glycerol (9.95-24.08%, mass versus starch mass) on films properties were evaluated by a rotational central composite 2 2 experimental design. Arrowroot starch showed high amylose content (35%). Low values were found for the swelling power and solubility index. The X-ray diffraction showed "C" type crystalline structures, while thermogram showed Tg around of 118 and 120 °C. The thermogravimetric analysis showed that 40% of mass loss of starch occurred between 330 and 410 °C. The films were homogeneous, transparent and manageable. Starch and glycerol concentrations played a significant role in thickness and solubility in water of films, but was not significant for water vapor permeability and tensile strength. Therefore, arrowroot is a very promising starch source for application in films. Copyright © 2018 Elsevier Ltd. All rights reserved.

Physicochemical and Mechanical Properties of Bambara Groundnut Starch Films Modified with Stearic Acid.

PubMed

Oyeyinka, Samson A; Singh, Suren; Amonsou, Eric O

2017-01-01

The physicochemical and mechanical properties of biofilm prepared from bambara starch modified with varying concentrations of stearic acid (0%, 2.5%, 3.5%, 5%, 7%, and 10%) were studied. By scanning electron microscopy, bambara starch films modified with stearic acid (≥3.5%) showed a progressively rough surface compared to those with 2.5% stearic acid and the control. Fourier transform infrared spectroscopy spectra revealed a peak shift of approximately 31 cm -1 , suggesting the promotion of hydrogen bond formation between hydroxyl groups of starch and stearic acid. The addition of 2.5% stearic acid to bambara starch film reduced water vapor permeability by approximately 17%. Bambara starch films modified with higher concentration of stearic acid were more opaque and showed significantly high melting temperatures. However, mechanical properties of starch films were generally negatively affected by stearic acid. Bambara starch film may be modified with 2.5% stearic acid for improved water vapor permeability and thermal stability with minimal effect on tensile strength. © 2016 Institute of Food Technologists®.

Dynamic moisture sorption characteristics of enzyme-resistant recrystallized cassava starch.

PubMed

Mutungi, Christopher; Schuldt, Stefan; Onyango, Calvin; Schneider, Yvonne; Jaros, Doris; Rohm, Harald

2011-03-14

The interaction of moisture with enzyme-resistant recrystallized starch, prepared by heat-moisture treatment of debranched acid-modified or debranched non-acid-modified cassava starch, was investigated in comparison with the native granules. Crystallinities of the powdered products were estimated by X-ray diffraction. Moisture sorption was determined using dynamic vapor sorption analyzer and data fitted to various models. Percent crystallinities of native starch (NS), non-acid-modified recrystallized starch (NAMRS), and acid-modified recrystallized starch (AMRS) were 39.7, 51.9, and 56.1%, respectively. In a(w) below 0.8, sorption decreased in the order NS > NAMRS > AMRS in line with increasing sample crystallinities but did not follow this crystallinity dependence at higher a(w) because of condensation and polymer dissolution effects. Adsorbed moisture became internally absorbed in NS but not in NAMRS and AMRS, which might explain the high resistance of the recrystallized starches to digestion because enzyme and starch cannot approach each other over fairly sufficient surface at the molecular level.

In situ study of maize starch gelatinization under ultra-high hydrostatic pressure using X-ray diffraction.

PubMed

Yang, Zhi; Gu, Qinfen; Hemar, Yacine

2013-08-14

The gelatinization of waxy (very low amylose) and high-amylose maize starches by ultra-high hydrostatic pressure (up to 6 GPa) was investigated in situ using synchrotron X-ray powder diffraction on samples held in a diamond anvil cell (DAC). The starch pastes, made by mixing starch and water in a 1:1 ratio, were pressurized and measured at room temperature. X-ray diffraction pattern showed that at 2.7 GPa waxy starch, which displayed A-type XRD pattern at atmospheric pressure, exhibited a faint B-type-like pattern. The B-type crystalline structures of high-amylose starch were not affected even when 1.5 GPa pressure was applied. However, both waxy and high-amylose maize starches can be fully gelatinized at 5.9 GPa and 5.1 GPa, respectively. In the case of waxy maize starch, upon release of pressure (to atmospheric pressure) crystalline structure appeared as a result of amylopectin aggregation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Rheological properties in relation to molecular structure of quinoa starch.

PubMed

Li, Guantian; Zhu, Fan

2018-07-15

Quinoa starch granules are small (~0.5 - 3μm) with potentials for some food and other applications. To better exploit it as a new starch resource, this study investigates the steady shear and dynamic oscillatory properties of 9 quinoa starches varying in composition and structure. Steady shear analysis shows that the flow curves could be well described by 4 selected mathematic models. Temperature sweep analysis reveals that the quinoa starch encounters a 4-stage process including 2 phase transitions. Structure-function relationship analysis showed that composition as well as unit and internal chain length distribution of amylopectin have significant impact on the rheological properties (e.g., G' at 90°C) of quinoa starch. The roles of some individual unit chains and super-long unit chains of amylopectin in determining the rheological properties of quinoa starch were revealed. This study may stimulate further interest in understanding the structural basis of starch rheology. Copyright © 2018 Elsevier B.V. All rights reserved.

Quinoa starch: Structure, properties, and applications.

PubMed

Li, Guantian; Zhu, Fan

2018-02-01

Quinoa (Chenopodium quinoa Willd.) has gained popularity worldwide largely due to the attractive nutritional profile. It also has much potential for food security due to the great genetic diversity. Starch is the main component of quinoa grain and makes up to 70% of the dry matter. The starch plays a crucial role in functional properties of quinoa and related food products. The starch granules are rather small (∼1-3μm) with relatively low amylose contents as compared with most of the other starches. Quinoa amylopectin has significant amounts of short chains and super-long chains. These unique features have generated research interest in using the starch for food and other applications such as creating Pickering emulsions. This review summarizes the present knowledge of the isolation, composition, granular and molecular structures, physicochemical properties, modifications, and applications of quinoa starch. It becomes obvious that this starch has great potential for food and nonfood applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterisation of cationic potato starch by asymmetrical flow field-flow fractionation. Influence of ionic strength and degree of substitution.

PubMed

Santacruz, Stalin

2014-06-15

The properties of a paper sheet depend on the absorption together with the physico-chemical properties of additives used in the paper processing. The effect of ionic strength and degree of substitution of cationic potato starch on the elution pattern of asymmetrical flow field-flow fractionation was analysed. The effect of starch derivatisation, in either dry or wet phase, was also investigated. Average molar mass showed no difference between the starches obtained from the two derivatisation processes. Apparent densities showed that dry cationic starch had higher density than wet cationic starch for a hydrodynamic radius between 50 and 100 nm. Elution times of native and three cationic starches increased when the ionic strength increased from 50 to 100mM. No differences in the molar mass among cationic starches with different degree of substitution suggested no degradation due to a derivatisation process. Large sample loads can be used at 100mM without overloading. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of modified starch technology (maltodextrin) from commercial tapioca on semi production scale using oil heater dextrinator

NASA Astrophysics Data System (ADS)

Triyono, Agus; Cecep Erwan Andriansyah, Raden; Luthfiyanti, Rohmah; Rahman, Taufik

2017-12-01

One way to improve functional starch is by modification of starch into dextrin or maltodextrin. Maltodextrin is used in the food industry as a food substitution. Development of enzymatically modified starch technology has been performed with the use of α-amylase at optimum pH of 5.5, temperature 75-85 °C, with enzyme activity of 135 KNU/g. The maltodextrin produced from commercial tapioca has the quality requirements for food according to SNI 1992. The yield of maltodextrin obtained is about 80%. The use of the optimum amount of the α-amylase enzyme is 0.07 % v/w and the substrate amount of tapioca starch is 35%. Analysis of the feasibility of modified starch with the assumption of production scale of 300 kg per day, the economic value of 10 years business, the price of starch is IDR 8,350/kg, from tapioca starch (tapioca) IDR 4,000 - IDR 4,500/kg.

Duodenal supply of glutamate and casein both improve intestinal starch digestion in cattle but by apparently different mechanisms.

PubMed

Brake, D W; Titgemeyer, E C; Anderson, D E

2014-09-01

Greater postruminal flows of protein increase small intestinal starch digestion in cattle. Our objective was to determine if small intestinal starch digestion is increased by duodenal supplementation of AA. We fed 5 duodenally and ileally cannulated steers a low-starch soybean hull-based diet in 5 × 5 Latin square designs and provided continuous duodenal infusion of raw cornstarch in combination with AA or casein and measured small intestinal starch digestion. In Exp. 1 treatments were continuous duodenal infusion of 1) no supplement (control), 2) casein (400 g/d), 3) crystalline AA similar in amount and AA composition to the casein (CASAA), 4) crystalline nonessential AA similar to those provided by casein, or 5) crystalline essential AA similar to those provided by casein. In Exp. 2 treatments were continuous duodenal infusion of 1) no supplement (control), 2) casein (400 g/d), 3) Glu (133 g/d), 4) Phe and Trp plus Met (30.4, 6.5, and 17.5 g/d, respectively; PTM), or 5) a combination of Glu and PTM. Duodenal infusion of casein increased (P ≤ 0.05) small intestinal starch digestion. When CASAA was infused, small intestinal starch digestion was similar (P = 0.30) to casein infusion. Infusion of only nonessential AA tended to increase (P = 0.14) small intestinal starch digestion relative to the control, but infusion of essential AA alone did not affect (P = 0.84) small intestinal starch digestion. In addition, infusion of casein or CASAA increased ileal flows of ethanol-soluble starch (small-chain α-glycosides), but nonessential AA alone were not different than the control. Duodenal infusion of Glu increased (P ≤ 0.05) small intestinal starch digestion, whereas PTM did not. Neither Glu nor PTM increased ileal flow of ethanol-soluble starch, but Glu and PTM provided together tended (P = 0.07) to increase ileal flows of small chain α-glycosides. Our data suggest that Glu alone can increase small intestinal starch digestion in cattle similar to casein, but increases in small intestinal starch digestion in response to Glu are not associated with an increase in ileal flows of small chain α-glycosides.

Quinoa Starch Characteristics and Their Correlations with the Texture Profile Analysis (TPA) of Cooked Quinoa.

PubMed

Wu, Geyang; Morris, Craig F; Murphy, Kevin M

2017-10-01

Starch characteristics significantly influence the functionality and end-use quality of cereals and pseudo-cereals. This study examined the composition and properties of starch from 11 pure varieties and 2 commercial samples of quinoa in relationship to the texture of cooked quinoa. Nearly all starch properties and characteristics differed among these samples. Results showed that total starch content of seeds ranged from 53.2 to 75.1 g/100 g apparent amylose content ranged from 2.7% to 16.9%; total amylose ranged from 4.7% to 17.3%; and the degree of amylose-lipid complex ranged from 3.4% to 43.3%. Amylose leaching ranged from 31 mg/100 g starch in "Japanese Strain" to 862 mg/100 g starch in "49ALC." "Japanese Strain" starch also exhibited the highest water solubility (4.5%) and the lowest swelling power (17). α-Amylase activity in "1ESP," "Col.#6197," "Japanese Strain," "QQ63," "Yellow Commercial," and "Red Commercial" (0.03 to 0.09 CU) were significantly lower than the levels of the other quinoa samples (0.20 to 1.16 CU). Additionally, gel texture, thermal properties, and pasting properties of quinoa starches were investigated. Lastly, correlation analysis showed that the quinoa samples with higher amylose content tended to yield harder, stickier, more cohesive, more gummy, and more chewy texture after cooking. A higher degree of amylose-lipid complex and amylose leaching were associated with softer and less chewy cooked quinoa TPA texture. Higher starch enthalpy correlated with firmer, more adhesive, more cohesive, and chewier texture. In sum, starch plays a significant role in the texture of cooked quinoa. The research determined starch characteristics among a diverse set of pure quinoa varieties and commercial samples, and identified the relationships between starch properties and cooked quinoa texture. The results can help breeders and food manufacturers to understand better the relationships among quinoa starch characteristics, cooked quinoa texture, and the best use of different cultivars. © 2017 Institute of Food Technologists®.

Enzyme-Catalyzed Regioselective Modification of Starch Nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakraborty, Soma; Sahoo, Bishwabhusan; Teraoka, Iwao

The selective esterification of starch nanoparticles was performed using as catalyst Candida antartica Lipase B (CAL-B) in its immobilized (Novozym 435) and free (SP-525) forms. The starch nanoparticles were made accessible for acylation reactions by formation of Aerosol-OT (AOT, bis(2-ethylhexyl)sodium sulfosuccinate) stabilized microemulsions. Starch nanoparticles in microemulsions were reacted with vinyl stearate, ε-caprolactone, and maleic anhydride at 40 °C for 48 h to give starch esters with degrees of substitution (DS) of 0.8, 0.6, and 0.4, respectively. Substitution occurred regioselectively at the C-6 position of the glucose repeat units. Infrared microspectroscopy (IRMS) revealed that AOT-coated starch nanoparticles diffuse into themore » outer 50 μm shell of catalyst beads. Thus, even though CAL-B is immobilized within a macroporous resin, CAL-B is sufficiently accessible to the starch nanoparticles. When free CAL-B was incorporated along with starch within AOT-coated reversed micelles, CAL-B was also active and catalyzed the acylation with vinyl stearate (24 h, 40 °C) to give DS = 0.5. After removal of surfactant from the modified starch nanoparticles, they were dispersed in DMSO or water and were shown to retain their nanodimensions.« less

Effect of Dietary-Resistant Starch on Inhibition of Colonic Preneoplasia and Wnt Signaling in Azoxymethane-Induced Rodent Models.

PubMed

Nelson, Bridget; Cray, Nicole; Ai, Yongfeng; Fang, Yinan; Liu, Peng; Whitley, Elizabeth M; Birt, Diane

2016-01-01

Dietary fiber has been reported to prevent preneoplastic colon lesions. The aim of this study was to determine the effect of resistant starches, novel dietary fibers, on the development of colonic preneoplasia and Wnt signaling in azoxymethane (AOM)-treated rats and mice fed resistant starches at 55% of the diet after AOM treatment. Another objective was to determine the effect of resistant starches on the development of preneoplasia in rats treated with antibiotics (Ab), administered between AOM treatment and resistant starch feeding. Diets containing resistant starches, high-amylose (HA7), high-amylose-octenyl succinic anhydride (OS-HA7), or high-amylose-stearic acid (SA-HA7) were compared with control cornstarch (CS). The resistant starch content of the diets did not alter the yield of colonic lesions but animals treated with AOM and fed the diet with the highest resistant starch content, SA-HA7 developed the highest average aberrant crypt foci (ACF) per animal. Mice fed the OS-HA7 diet had decreased expression of some upstream Wnt genes in the colonic crypts. This study suggests that further research is needed to determine if resistant starch impacts colon carcinogenesis in rodents.

New perspectives of starch: Synthesis and in vitro assessment of novel thiolated mucoadhesive derivatives.

PubMed

Jelkmann, Max; Bonengel, Sonja; Menzel, Claudia; Markovic, Svetislav; Bernkop-Schnürch, Andreas

2018-05-11

The purpose of this study was to develop a novel thiolated starch polymer with improved mucoadhesive properties by conjugation of cysteamine to starch as a natural polymer of restricted mucoadhesive properties. Aldehyde substructures were integrated into starch via oxidative cleavage of vicinal diols by increasing amounts of sodium periodate followed by covalent attachment of cysteamine to oxidized starch via reductive amination. Thiol groups were quantified via Ellman's reaction and their impact on mucoadhesion was analyzed by rheological investigations, the rotating cylinder method and tensile studies on porcine mucosa. The total amount of immobilized thiol groups revealed a correlation between degree of oxidation and thiolation. Modified starch demonstrated an up to 1.66-fold increase in water uptake in comparison to native starch. Modification of starch resulted in greatly improved cohesive properties and improvement in mucoadhesion. Rheological investigations revealed a 2- to 4-fold rise in viscosity of mucus. Tensile studies revealed a linear correlation between degree of oxidation/thiolation and enhancement of maximum detachment force and total work adhesion. In terms of these results, thiolated starch is a new, promising, polymer in the field of mucoadhesive drug delivery systems. Copyright © 2018 Elsevier B.V. All rights reserved.

Regulatory principles and experimental approaches to the circadian control of starch turnover

PubMed Central

Seaton, Daniel D.; Ebenhöh, Oliver; Millar, Andrew J.; Pokhilko, Alexandra

2014-01-01

In many plants, starch is synthesized during the day and degraded during the night to avoid carbohydrate starvation in darkness. The circadian clock participates in a dynamic adjustment of starch turnover to changing environmental condition through unknown mechanisms. We used mathematical modelling to explore the possible scenarios for the control of starch turnover by the molecular components of the plant circadian clock. Several classes of plausible models were capable of describing the starch dynamics observed in a range of clock mutant plants and light conditions, including discriminating circadian protocols. Three example models of these classes are studied in detail, differing in several important ways. First, the clock components directly responsible for regulating starch degradation are different in each model. Second, the intermediate species in the pathway may play either an activating or inhibiting role on starch degradation. Third, the system may include a light-dependent interaction between the clock and downstream processes. Finally, the clock may be involved in the regulation of starch synthesis. We discuss the differences among the models’ predictions for diel starch profiles and the properties of the circadian regulators. These suggest additional experiments to elucidate the pathway structure, avoid confounding results and identify the molecular components involved. PMID:24335560

Films based on oxidized starch and cellulose from barley.

PubMed

El Halal, Shanise Lisie Mello; Colussi, Rosana; Deon, Vinícius Gonçalves; Pinto, Vânia Zanella; Villanova, Franciene Almeida; Carreño, Neftali Lenin Villarreal; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2015-11-20

Starch and cellulose fibers were isolated from grains and the husk from barley, respectively. Biodegradable films of native starch or oxidized starches and glycerol with different concentrations of cellulose fibers (0%, 10% and 20%) were prepared. The films were characterized by morphological, mechanical, barrier, and thermal properties. Cellulose fibers isolated from the barley husk were obtained with 75% purity and high crystallinity. The morphology of the films of the oxidized starches, regardless of the fiber addition, was more homogeneous as compared to the film of the native starch. The addition of cellulose fibers in the films increased the tensile strength and decreased elongation. The water vapor permeability of the film of oxidized starch with 20% of cellulose fibers was lower than the without fibers. However the films with cellulose fibers had the highest decomposition with the initial temperature and thermal stability. The oxidized starch and cellulose fibers from barley have a good potential for use in packaging. The addition of cellulose fibers in starch films can contribute to the development of films more resistant that can be applied in food systems to maintain its integrity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of alkali and oxidative treatments on the physicochemical, pasting, thermal and morphological properties of corn starch.

PubMed

Spier, Franciela; Zavareze, Elessandra da Rosa; Marques e Silva, Ricardo; Elias, Moacir Cardoso; Dias, Alvaro Renato Guerra

2013-07-01

Few studies on starch modifications using different chemical agents are available in the literature, and no reports were found on the combined effect of oxidation and alkaline treatment of corn starch. Thus this work evaluated the physicochemical, pasting, morphological, cystallinity and thermal properties of chemically modified corn starch, after either the isolated or combined action of alkaline (sodium hydroxide) and oxidative (sodium hypochlorite) treatments. The highest values for the sum of carbonyl and carboxyl and enzymatic hydrolysis occurred in starches submitted to oxidative treatment at high active chlorine concentrations. The alkali treatment in isolation modified the pasting properties, reduced the paste temperature and increased the peak viscosity, breakdown, final viscosity and setback of starches. Starch modified by the action of sodium hypochlorite and hydroxide in combination presented more severe damage on granule surfaces. The results show that corn starch modified by the combined action of oxidative and alkaline treatments should be studied more, especially at the concentration limit of sodium hydroxide where gelatinization occurs. Under these conditions the effect of oxidation can be more intense and thus allow the production of starches with different properties and an increase in their industrial applications. © 2013 Society of Chemical Industry.

Critical and speculative review of the roles of multi-protein complexes in starch biosynthesis in cereals.

PubMed

Crofts, Naoko; Nakamura, Yasunori; Fujita, Naoko

2017-09-01

Starch accounts for the majority of edible carbohydrate resources generated through photosynthesis. Amylopectin is the major component of starch and is one of highest-molecular-weight biopolymers. Rapid and systematic synthesis of frequently branched hydro-insoluble amylopectin and efficient accumulation into amyloplasts of cereal endosperm is crucial. The functions of multiple starch biosynthetic enzymes, including elongation, branching, and debranching enzymes, must be temporally and spatially coordinated. Accordingly, direct evidence of protein-protein interactions of starch biosynthetic enzymes were first discovered in developing wheat endosperm in 2004, and they have since been shown in the developing seeds of other cereals. This review article describes structural characteristics of starches as well as similarities and differences in protein complex formation among different plant species and among mutant plants that are deficient in specific starch biosynthetic enzymes. In addition, evidence for protein complexes that are involved in the initiation stages of starch biosynthesis is summarized. Finally, we discuss the significance of protein complexes and describe new methods that may elucidate the mechanisms and roles of starch biosynthetic enzyme complexes. Copyright © 2017 Elsevier B.V. All rights reserved.

Slow digestion property of octenyl succinic anhydride modified waxy maize starch in the presence of tea polyphenols.

PubMed

Peng, Shanli; Xue, Lei; Leng, Xue; Yang, Ruobing; Zhang, Genyi; Hamaker, Bruce R

2015-03-18

The in vivo slow digestion property of octenyl succinic anhydride modified waxy corn starch (OSA-starch) in the presence of tea polyphenols (TPLs) was studied. Using a mouse model, the experimental results showed an extended and moderate postprandial glycemic response with a delayed and significantly decreased blood glucose peak of OSA-starch after cocooking with TPLs (5% starch weight base). Further studies revealed an increased hydrodynamic radius of OSA-starch molecules indicating an interaction between OSA-starch and TPLs. Additionally, decreased gelatinization temperature and enthalpy and reduced viscosity and emulsifiability of OSA-starch support their possible complexation to form a spherical OSA-starch-TPLs (OSAT) complex. The moderate and extended postprandial glycemic response is likely caused by decreased activity of mucosal α-glucosidase, which is noncompetitively inhibited by tea catechins released from the complex during digestion. Meanwhile, a significant decrease of malondialdehyde (MDA) and increased DPPH free radical scavenging activity in small intestine tissue demonstrated the antioxidative functional property of the OSAT complex. Thus, the complex of OSAT, acting as a functional carbohydrate material, not only leads to a flattened and prolonged glycemic response but also reduces the oxidative stress, which might be beneficial to health.

Concerted suppression of all starch branching enzyme genes in barley produces amylose-only starch granules

PubMed Central

2012-01-01

Background Starch is stored in higher plants as granules composed of semi-crystalline amylopectin and amorphous amylose. Starch granules provide energy for the plant during dark periods and for germination of seeds and tubers. Dietary starch is also a highly glycemic carbohydrate being degraded to glucose and rapidly absorbed in the small intestine. But a portion of dietary starch, termed “resistant starch” (RS) escapes digestion and reaches the large intestine, where it is fermented by colonic bacteria producing short chain fatty acids (SCFA) which are linked to several health benefits. The RS is preferentially derived from amylose, which can be increased by suppressing amylopectin synthesis by silencing of starch branching enzymes (SBEs). However all the previous works attempting the production of high RS crops resulted in only partly increased amylose-content and/or significant yield loss. Results In this study we invented a new method for silencing of multiple genes. Using a chimeric RNAi hairpin we simultaneously suppressed all genes coding for starch branching enzymes (SBE I, SBE IIa, SBE IIb) in barley (Hordeum vulgare L.), resulting in production of amylose-only starch granules in the endosperm. This trait was segregating 3:1. Amylose-only starch granules were irregularly shaped and showed peculiar thermal properties and crystallinity. Transgenic lines retained high-yield possibly due to a pleiotropic upregualtion of other starch biosynthetic genes compensating the SBEs loss. For gelatinized starch, a very high content of RS (65 %) was observed, which is 2.2-fold higher than control (29%). The amylose-only grains germinated with same frequency as control grains. However, initial growth was delayed in young plants. Conclusions This is the first time that pure amylose has been generated with high yield in a living organism. This was achieved by a new method of simultaneous suppression of the entire complement of genes encoding starch branching enzymes. We demonstrate that amylopectin is not essential for starch granule crystallinity and integrity. However the slower initial growth of shoots from amylose-only grains may be due to an important physiological role played by amylopectin ordered crystallinity for rapid starch remobilization explaining the broad conservation in the plant kingdom of the amylopectin structure. PMID:23171412

Characterization of pinto bean high-starch fraction after air classification and extrustion

USDA-ARS?s Scientific Manuscript database

The properties of three bean flours (whole, high-starch fraction, and extruded) were studied to determine their potential applications. Significant differences in moisture, protein, resistant starch, total starch, lipids, ash, phytic acid, amino acid content, and fatty acid profile were observed amo...

Enzymatic method for measuring starch gelatinization in dry products in situ

USDA-ARS?s Scientific Manuscript database

An enzymatic method based on hydrolysis of starch by amyloglucosidase and measurement of D-glucose released by glucose oxidase-peroxidase was developed to measure both gelatinized starch and hydrolyzable starch in situ of dried starchy products. Efforts focused on the development of sample handling ...

77 FR 43601 - Risks and Benefits of Hydroxyethyl Starch Solutions; Public Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-25

...] Risks and Benefits of Hydroxyethyl Starch Solutions; Public Workshop AGENCY: Food and Drug... public workshop entitled: ``Risks and Benefits of Hydroxyethyl Starch Solutions.'' The purpose of this... starch (HES) solutions. The public workshop has been planned in partnership with the Department of...

Studies of Amylose Content in Potato Starch

USDA-ARS?s Scientific Manuscript database

Potato starch is typically low in amylose (~20-25%), but high amylose starch has superior nutritional qualities. The ratio between amylose and amylopectin is the most important property influencing the physical properties of starch. There is a strong case to be made for the development of food crops...

Amylose Content in Tuber Starch of Wild Potato Species

USDA-ARS?s Scientific Manuscript database

Approximately 20% of potato tuber fresh weight is starch, which is composed of amylose (straight chains of glucose) and amylopectin (branched chains). Potato starch is low in amylose (~25%), but high amylose starch has superior nutritional qualities. Amylose content has been determined in tuber samp...

Allelic variants of the amylose extender mutation of maize demonstrate phenotypic variation in starch structure resulting from modified protein–protein interactions

PubMed Central

Liu, Fushan; Ahmed, Zaheer; Lee, Elizabeth A.; Donner, Elizabeth; Liu, Qiang; Ahmed, Regina; Morell, Matthew K.; Emes, Michael J.; Tetlow, Ian J.

2012-01-01

amylose extender (ae−) starches characteristically have modified starch granule morphology resulting from amylopectin with reduced branch frequency and longer glucan chains in clusters, caused by the loss of activity of the major starch branching enzyme (SBE), which in maize endosperm is SBEIIb. A recent study with ae− maize lacking the SBEIIb protein (termed ae1.1 herein) showed that novel protein–protein interactions between enzymes of starch biosynthesis in the amyloplast could explain the starch phenotype of the ae1.1 mutant. The present study examined an allelic variant of the ae− mutation, ae1.2, which expresses a catalytically inactive form of SBEIIb. The catalytically inactive SBEIIb in ae1.2 lacks a 28 amino acid peptide (Val272–Pro299) and is unable to bind to amylopectin. Analysis of starch from ae1.2 revealed altered granule morphology and physicochemical characteristics distinct from those of the ae1.1 mutant as well as the wild-type, including altered apparent amylose content and gelatinization properties. Starch from ae1.2 had fewer intermediate length glucan chains (degree of polymerization 16–20) than ae1.1. Biochemical analysis of ae1.2 showed that there were differences in the organization and assembly of protein complexes of starch biosynthetic enzymes in comparison with ae1.1 (and wild-type) amyloplasts, which were also reflected in the composition of starch granule-bound proteins. The formation of stromal protein complexes in the wild-type and ae1.2 was strongly enhanced by ATP, and broken by phosphatase treatment, indicating a role for protein phosphorylation in their assembly. Labelling experiments with [γ-32P]ATP showed that the inactive form of SBEIIb in ae1.2 was phosphorylated, both in the monomeric form and in association with starch synthase isoforms. Although the inactive SBEIIb was unable to bind starch directly, it was strongly associated with the starch granule, reinforcing the conclusion that its presence in the granules is a result of physical association with other enzymes of starch synthesis. In addition, an Mn2+-based affinity ligand, specific for phosphoproteins, was used to show that the granule-bound forms of SBEIIb in the wild-type and ae1.2 were phosphorylated, as was the granule-bound form of SBEI found in ae1.2 starch. The data strongly support the hypothesis that the complement of heteromeric complexes of proteins involved in amylopectin synthesis contributes to the fine structure and architecture of the starch granule. PMID:22121198

Resistant starch prevents tumorigenesis of dimethylhydrazine-induced colon tumors via regulation of an ER stress-mediated mitochondrial apoptosis pathway.

PubMed

Wang, Qiuyu; Wang, Peng; Xiao, Zhigang

2018-04-01

Resistant starch is as common soluble fiber that escapes digestion in the small intestine and can regulate intestinal function, metabolism of blood glucose and lipids, and may prevent tumorigenesis of gastrointestinal cancer. Epidemiology and other evidence have suggested that resistant starch may prevent colon cancer development. The aim of the current study was to explore the ameliorative effects and potential mechanisms of resistant starch in the tumorigenesis of colon tumors induced by dimethylhydrazine in C57BL/6 mice. Western blot analysis, ELISA, microscopy, immunofluorescence and immunohistochemistry were used to analyze the efficacy of resistant starch on the metabolic balance in the colon and tumorigenesis of colon tumors. The results demonstrated that a diet containing resistant starch decreased the animal body weight and reduced free ammonia, pH and short chain fatty acids in feces compared with mice that received a standard diet. Resistant starch reduced the incidence of colon tumors and suppressed the expression of carcinogenesis‑associated proteins, including heat shock protein 25, protein kinase C‑d and gastrointestinal glutathione peroxidase in colon epithelial cells compared with standard starch and control groups. Colon tumor cells proliferation and dedifferentiation were significantly decreased by a resistant starch diet. The results also demonstrated that resistant starch increased the apoptosis of colon tumor cells through regulation of apoptosis‑associated gene expression levels in colon tumor cells. Oxidative stress and endoplasmic reticulum stress were upregulated, and elevation eukaryotic translation initiation factor 2α (eIF2α), activating transcription factor‑4 and secretase‑β expression levels were increased in the resistant starch diet group. Additionally, the activity of eIF2α and PERK were increased in colon tumor cells from mice that had received resistant starch. Increasing DNA damage‑inducible transcript 3 protein (CHOP), binding immunoglobulin protein (BIP) and caspase‑12 expression levels upregulated by resistant starch diet may contribute to the resistant starch‑induced apoptosis of colon tumor cells induced by 1,2‑dimethylhydrazine. In vitro assays demonstrated that knockdown of eIF2α inhibited apoptosis of colon tumor cells isolated from mice fed with resistant starch, which also downregulated CHOP, BIP and caspase‑3 expression levels compared with controls. Furthermore, long‑term survival of experimental mice was prolonged by the resistant starch diet compared with the standard diet group. In conclusion, the results indicate that resistant starch in the diet may prevent carcinogenesis of colon epithelial cells, mediated by enhancing apoptosis through an endoplasmic reticulum stress‑mediated mitochondrial apoptosis pathway.

Lytic polysaccharide monooxygenases and other oxidative enzymes are abundantly secreted by Aspergillus nidulans grown on different starches.

PubMed

Nekiunaite, Laura; Arntzen, Magnus Ø; Svensson, Birte; Vaaje-Kolstad, Gustav; Abou Hachem, Maher

2016-01-01

Starch is the second most abundant plant-derived biomass and a major feedstock in non-food industrial applications and first generation biofuel production. In contrast to lignocellulose, detailed insight into fungal degradation of starch is currently lacking. This study explores the secretomes of Aspergillus nidulans grown on cereal starches from wheat and high-amylose (HA) maize, as well as legume starch from pea for 5 days. Aspergillus nidulans grew efficiently on cereal starches, whereas growth on pea starch was poor. The secretomes at days 3-5 were starch-type dependent as also reflected by amylolytic activity measurements. Nearly half of the 312 proteins in the secretomes were carbohydrate-active enzymes (CAZymes), mostly glycoside hydrolases (GHs) and oxidative auxiliary activities (AAs). The abundance of the GH13 α-amylase (AmyB) decreased with time, as opposed to other starch-degrading enzymes, e.g., the GH13 AmyF, GH15 glucoamylases (GlaA and GlaB), and the GH31 α-glucosidase (AgdE). Two AA13 LPMOs displayed similar secretion patterns as amylolytic hydrolases and were among the most abundant CAZymes. The starch-active AnLPMO13A that possesses a CBM20 carbohydrate-binding module dominated the starch-binding secretome fraction. A striking observation is the co-secretion of several redox-active enzymes with the starch-active AA13 LPMOs and GHs, some at high abundance. Notably nine AA9 LPMOs, six AA3 sub-family 2 (AA_2) oxidoreductases, and ten AA7 glyco-oligosaccharide oxidases were identified in the secretomes in addition to other non-CAZyme oxidoreductases. The co-secretion and high abundance of AA13 LPMOs are indicative of a key role in starch granule deconstruction. The increase in AA13 LPMO abundance with culture time may reflect accumulation of a more resistant starch fraction towards the later stages of the culture. The identification of AmyR sites upstream AA13 LPMOs unveils co-regulation of LPMOs featuring in starch utilization. Differential deployment of amylolytic hydrolases and LPMOs over time suggests additional regulatory mechanisms. The abundant co-secretion of distinct AA3 and AA7 oxidoreductases merits further studies into their roles and possible interplay with LPMOs and other enzymes in the deconstruction of starchy substrates. The study reports for the first time the biological significance of LPMOs in starch degradation and the temporal interplay between these and amylolytic hydrolases.

THE SYNTHESIS OF THE STARCH GRANULE.

PubMed

Smith, A. M.; Denyer, K.; Martin, C.

1997-06-01

This review describes and discusses the implications of recent discoveries about how starch polymers are synthesized and organized to form a starch granule. Three issues are highlighted. 1. The role and importance of ADPglucose pyrophosphorylase in the generation of ADPglucose as the substrate for polymer synthesis. 2. The contributions of isoforms of starch-branching enzyme, starch synthase, and debranching enzyme to the synthesis and ordered packing of amylopectin molecules. 3. The requirements for and regulation of the synthesis of amylose.

Impact of down-regulation of starch branching enzyme IIb in rice by artificial microRNA- and hairpin RNA-mediated RNA silencing

PubMed Central

Butardo, Vito M.; Fitzgerald, Melissa A.; Bird, Anthony R.; Gidley, Michael J.; Flanagan, Bernadine M.; Larroque, Oscar; Resurreccion, Adoracion P.; Laidlaw, Hunter K. C.; Jobling, Stephen A.; Morell, Matthew K.; Rahman, Sadequr

2011-01-01

The inactivation of starch branching IIb (SBEIIb) in rice is traditionally associated with elevated apparent amylose content, increased peak gelatinization temperature, and a decreased proportion of short amylopectin branches. To elucidate further the structural and functional role of this enzyme, the phenotypic effects of down-regulating SBEIIb expression in rice endosperm were characterized by artificial microRNA (amiRNA) and hairpin RNA (hp-RNA) gene silencing. The results showed that RNA silencing of SBEIIb expression in rice grains did not affect the expression of other major isoforms of starch branching enzymes or starch synthases. Structural analyses of debranched starch showed that the doubling of apparent amylose content was not due to an increase in the relative proportion of amylose chains but instead was due to significantly elevated levels of long amylopectin and intermediate chains. Rices altered by the amiRNA technique produced a more extreme starch phenotype than those modified using the hp-RNA technique, with a greater increase in the proportion of long amylopectin and intermediate chains. The more pronounced starch structural modifications produced in the amiRNA lines led to more severe alterations in starch granule morphology and crystallinity as well as digestibility of freshly cooked grains. The potential role of attenuating SBEIIb expression in generating starch with elevated levels of resistant starch and lower glycaemic index is discussed. PMID:21791436

Evaluation of the Significance of Starch Surface Binding Sites on Human Pancreatic α-Amylase.

PubMed

Zhang, Xiaohua; Caner, Sami; Kwan, Emily; Li, Chunmin; Brayer, Gary D; Withers, Stephen G

2016-11-01

Starch provides the major source of caloric intake in many diets. Cleavage of starch into malto-oligosaccharides in the gut is catalyzed by pancreatic α-amylase. These oligosaccharides are then further cleaved by gut wall α-glucosidases to release glucose, which is absorbed into the bloodstream. Potential surface binding sites for starch on the pancreatic amylase, distinct from the active site of the amylase, have been identified through X-ray crystallographic analyses. The role of these sites in the degradation of both starch granules and soluble starch was probed by the generation of a series of surface variants modified at each site to disrupt binding. Kinetic analysis of the binding and/or cleavage of substrates ranging from simple maltotriosides to soluble starch and insoluble starch granules has allowed evaluation of the potential role of each such surface site. In this way, two key surface binding sites, on the same face as the active site, are identified. One site, containing a pair of aromatic residues, is responsible for attachment to starch granules, while a second site featuring a tryptophan residue around which a malto-oligosaccharide wraps is shown to heavily influence soluble starch binding and hydrolysis. These studies provide insights into the mechanisms by which enzymes tackle the degradation of largely insoluble polymers and also present some new approaches to the interrogation of the binding sites involved.

Starch Turnover and Metabolism during Flower and Early Embryo Development1[CC-BY

PubMed Central

Pazmino, Diana; Gagliardini, Valeria

2016-01-01

The accumulation of starch within photosynthetic tissues and within dedicated storage organs has been characterized extensively in many species, and a function in buffering carbon availability or in fueling later growth phases, respectively, has been proposed. However, developmentally regulated starch turnover within heterotrophic tissues other than dedicated storage organs is poorly characterized, and its function is not well understood. Here, we report on the characterization of starch turnover during flower, early embryo, and silique development in Arabidopsis (Arabidopsis thaliana) using a combined clearing-staining technique on whole-mount tissue. Besides the two previously documented waves of transient starch accumulation in the stamen envelope, occurring during meiosis and pollen mitosis I, we identified a novel, third wave of starch amylogenesis/amylolysis during the last stages of stamen development. To gain insights into the underlying molecular mechanisms, we analyzed publicly available microarray data, which revealed a developmentally coordinated expression of carbohydrate transport and metabolism genes during these waves of transient starch accumulation. Based on this analysis, we characterized starch dynamics in mutants affecting hexose phosphate metabolism and translocation, and identified the Glc-6-phosphate/phosphate antiporter GPT1 as the putative translocator of Glc-6-phosphate for starch biosynthesis in reproductive tissues. Based on these results, we propose a model of starch synthesis within the pollen grain and discuss the nutrient transport route feeding the embryo within the developing seed. PMID:27794100

The Mechanism of Starch Over-Accumulation in Chlamydomonas reinhardtii High-Starch Mutants Identified by Comparative Transcriptome Analysis

PubMed Central

Koo, Kwang M.; Jung, Sera; Lee, Beom S.; Kim, Jin-Baek; Jo, Yeong D.; Choi, Hong-Il; Kang, Si-Yong; Chung, Gook-H.; Jeong, Won-Joong; Ahn, Joon-Woo

2017-01-01

The focus of this study was the mechanism of starch accumulation in Chlamydomonas reinhardtii high-starch mutants. Three C. reinhardtii mutants showing high-starch content were generated using gamma irradiation. When grown under nitrogen-deficient conditions, these mutants had more than twice as much starch than a wild-type control. The mechanism of starch over-accumulation in these mutants was studied with comparative transcriptome analysis. In all mutants, induction of phosphoglucomutase 1 (PGM1) expression was detected; PGM1 catalyzes the inter-conversion of glucose 1-phosphate and glucose 6-phosphate in both starch biosynthetic and glycolytic pathway. Interestingly, transcript levels of phosphoglucose isomerase 1 (PGI1), fructose 1,6-bisphosphate aldolase 1 and 2 (FBA1 and FBA2) were down-regulated in all mutants; PGI1, FBA1, and FBA2 act on downstream of glucose 6-phosphate conversion in glycolytic pathway. Therefore, down-regulations of PGI1, FBA1, and FBA2 may lead to accumulation of upstream metabolites, notably glucose 6-phosphate, resulting in induction of PGM1 expression through feed-forward regulation and that PGM1 overexpression caused starch over-accumulation in mutants. These results suggest that PGI1, FBA1, FBA2, and PGM1 correlate with each other in terms of coordinated transcriptional regulation and play central roles for starch over-accumulation in C. reinhardtii. PMID:28588557

13C-Labeled-Starch Breath Test in Congenital Sucrase-isomaltase Deficiency.

PubMed

Robayo-Torres, Claudia C; Diaz-Sotomayor, Marisela; Hamaker, Bruce R; Baker, Susan S; Chumpitazi, Bruno P; Opekun, Antone R; Nichols, Buford L

2018-06-01

Human starch digestion is a multienzyme process involving 6 different enzymes: salivary and pancreatic α-amylase; sucrase and isomaltase (from sucrose-isomaltase [SI]), and maltase and glucoamylase (from maltase-glucoamylase [MGAM]). Together these enzymes cleave starch to smaller molecules ultimately resulting in the absorbable monosaccharide glucose. Approximately 80% of all mucosal maltase activity is accounted for by SI and the reminder by MGAM. Clinical studies suggest that starch may be poorly digested in those with congenital sucrase-isomaltase deficiency (CSID). Poor starch digestion occurs in individuals with CSID and can be documented using a noninvasive C-breath test (BT). C-Labled starch was used as a test BT substrate in children with CSID. Sucrase deficiency was previously documented in study subjects by both duodenal biopsy enzyme assays and C-sucrose BT. Breath CO2 was quantitated at intervals before and after serial C-substrate loads (glucose followed 75 minutes later by starch). Variations in metabolism were normalized against C-glucose BT (coefficient of glucose absorption). Control subjects consisted of healthy family members and a group of children with functional abdominal pain with biopsy-proven sucrase sufficiency. Children with CSID had a significant reduction of C-starch digestion mirroring that of their duodenal sucrase and maltase activity and C-sucrase BT. In children with CSID, starch digestion may be impaired. In children with CSID, starch digestion correlates well with measures of sucrase activity.

In vitro digestibility of normal and waxy corn starch is modified by the addition of Tween 80.

PubMed

Vernon-Carter, E J; Alvarez-Ramirez, J; Bello-Perez, L A; Garcia-Hernandez, A; Roldan-Cruz, C; Garcia-Diaz, S

2018-05-15

Aqueous dispersions of normal and waxy corn starch (3% w/w) were mixed with Tween 80 (0, 7.5, 15, 22.5 and 30 g/100 g of starch), and gelatinized (90 °C, 20 min). Optical microscopy of the gelatinized starch dispersions (GSD x ; x = Tween 80 concentration) revealed that the microstructure was characterized by a continuous phase of leached amylose and amylopectin entangled chains, and a dispersed phase of insoluble remnants, called ghosts, on whose surface small granules were observed, imputed to Tween 80. The apparent viscosity of the GSD x decreased as the concentration of Tween 80 increased (up to about 70-90%). FTIR analysis of dried GSD x indicated that Tween 80 addition decreased short-range ordering. The content of rapidly digestible starch (RDS) and resistant starch (RS) fractions tended to increase significantly, at the expense of a significant decrease of slowly digestible starch (SDS) fraction, an effect that may be attributed to the increase of amorphous structures and starch chain-surfactant complexes. The RDS and RS increase was more pronounced for normal than for waxy corn starch, and the significance of the increase was dependent on Tween 80 concentration. Overall, the results showed that surfactant can affect largely the digestibility of starch chains. Copyright © 2018 Elsevier B.V. All rights reserved.

Determination of hydrophobicity of dry-heated wheat starch granules using sucrose fatty acid esters (SFAE).

PubMed

Tabara, Aya; Oneda, Hiroshi; Murayama, Ryuji; Matsui, Yuko; Hirano, Akira; Seguchi, Masaharu

2014-01-01

Sucrose fatty acid esters (SFAE) were adsorbed onto dry-heated (120 °C for 10, 20, 40, 60, and 120 min) wheat starch granules and extracted with ethyl ether in a Soxhlet apparatus without gelatinization of the starch granules. The amount of sucrose in the extracted SFAE was determined by the phenol sulfate method. A gradual increase of the sucrose from 159 to 712 μg, in SFAE per gram of starch, occurred with increasing dry-heating time and demonstrated the increased hydrophobicity of the starch granules. Increase of the SFAE was highly correlated (r = 0.9816) to increase of the oil-binding capacity of the dry-heated wheat starch granules. Non-waxy rice, waxy rice, sweet potato, and potato starch granules also showed higher hydrophobicity after dry-heating by this method.

Structural, morphological, and physicochemical properties of acetylated high-, medium-, and low-amylose rice starches.

PubMed

Colussi, Rosana; Pinto, Vania Zanella; El Halal, Shanise Lisie Mello; Vanier, Nathan Levien; Villanova, Franciene Almeida; Marques E Silva, Ricardo; da Rosa Zavareze, Elessandra; Dias, Alvaro Renato Guerra

2014-03-15

The high-, medium-, and low-amylose rice starches were isolated by the alkaline method and acetylated by using acetic anhydride for 10, 30, and 90 min of reaction. The degree of substitution (DS), the Fourier-transformed infrared spectroscopy (FTIR), the X-ray diffractograms, the thermal, morphological, and pasting properties, and the swelling power and solubility of native and acetylated starches were evaluated. The DS of the low-amylose rice starch was higher than the DS of the medium- and the high-amylose rice starches. The introduction of acetyl groups was confirmed by FTIR spectroscopy. The acetylation treatment reduced the crystallinity, the viscosity, the swelling power, and the solubility of rice starch; however, there was an increase in the thermal stability of rice starch modified by acetylation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis of thermal and chemical resistant oxygen barrier starch with reinforcement of nano silicon carbide.

PubMed

Dash, Satyabrata; Swain, Sarat K

2013-09-12

Starch/silicon carbide (starch/SiC) bionanocomposites were synthesized by solution method using different wt% of silicon carbide with starch matrix. The interaction between starch and silicon carbide was studied by Fourier transform infrared (FTIR) spectroscopy. The structure of the bionanocomposites was investigated by X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). Thermal property of starch/SiC bionanocomposites was measured and a significant enhancement of thermal resistance was noticed. The oxygen barrier property of the composites was studied and a substantial reduction in permeability was observed as compared to the virgin starch. The reduction of oxygen permeability with enhancement of thermal stability of prepared bionanocomposites may enable the materials suitable for thermal resistant packaging and adhesive applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of Acacia Gum, NaCl, and Sucrose on Physical Properties of Lotus Stem Starch

PubMed Central

Gill, Balmeet Singh

2014-01-01

Consumer preferences in east Asian part of the world pave the way for consumption of lotus stem starch (LSS) in preparations such as breakfast meals, fast foods, and traditional confectioneries. The present study envisaged the investigation and optimization of additives, that is, acacia gum, sodium chloride (NaCl), and sucrose, on water absorption (WA), water absorption index (WAI), and water solubility index (WSI) of LSS employing response surface methodology (RSM). Acacia gum resulted in increased water uptake and swelling of starch; however, NaCl reduced the swelling power of starch by making water unavailable to starch and also due to starch-ion electrostatic interaction. Sucrose restricted the water absorption by binding free water and decreased amylose leaching by building bridges with starch chains and thus forming rigid structure. PMID:26904639

Microscopic Analysis of Corn Fiber Using Corn Starch- and Cellulose-Specific Molecular Probes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, S. E.; Donohoe, B. S.; Beery, K. E.

Ethanol is the primary liquid transportation fuel produced from renewable feedstocks in the United States today. The majority of corn grain, the primary feedstock for ethanol production, has been historically processed in wet mills yielding products such as gluten feed, gluten meal, starch, and germ. Starch extracted from the grain is used to produce ethanol in saccharification and fermentation steps; however the extraction of starch is not 100% efficient. To better understand starch extraction during the wet milling process, we have developed fluorescent probes that can be used to visually localize starch and cellulose in samples using confocal microscopy. Thesemore » probes are based on the binding specificities of two types of carbohydrate binding modules (CBMs), which are small substrate-specific protein domains derived from carbohydrate degrading enzymes. CBMs were fused, using molecular cloning techniques, to a green fluorescent protein (GFP) or to the red fluorescent protein DsRed (RFP). Using these engineered probes, we found that the binding of the starch-specific probe correlates with starch content in corn fiber samples. We also demonstrate that there is starch internally localized in the endosperm that may contribute to the high starch content in corn fiber. We also surprisingly found that the cellulose-specific probe did not bind to most corn fiber samples, but only to corn fiber that had been hydrolyzed using a thermochemical process that removes the residual starch and much of the hemicellulose. Our findings should be of interest to those working to increase the efficiency of the corn grain to ethanol process.« less

Robust and biodegradable elastomers based on corn starch and polydimethylsiloxane (PDMS).

PubMed

Ceseracciu, Luca; Heredia-Guerrero, José Alejandro; Dante, Silvia; Athanassiou, Athanassia; Bayer, Ilker S

2015-02-18

Designing starch-based biopolymers and biodegradable composites with durable mechanical properties and good resistance to water is still a challenging task. Although thermoplastic (destructured) starch has emerged as an alternative to petroleum-based polymers, its poor dimensional stability under humid and dry conditions extensively hinders its use as the biopolymer of choice in many applications. Unmodified starch granules, on the other hand, suffer from incompatibility, poor dispersion, and phase separation issues when compounded into other thermoplastics above a concentration level of 5%. Herein, we present a facile biodegradable elastomer preparation method by incorporating large amounts of unmodified corn starch, exceeding 80% by volume, in acetoxy-polyorganosiloxane thermosets to produce mechanically robust, hydrophobic bioelastomers. The naturally adsorbed moisture on the surface of starch enables autocatalytic rapid hydrolysis of polyorganosiloxane to form Si-O-Si networks. Depending on the amount of starch granules, the mechanical properties of the bioelastomers can be easily tuned with high elastic recovery rates. Moreover, starch granules considerably lowered the surface friction coefficient of the polyorganosiloxane network. Stress relaxation measurements indicated that the bioelastomers have strain energy dissipation factors that are lower than those of conventional rubbers, rendering them as promising green substitutes for plastic mechanical energy dampeners. Corn starch granules also have excellent compatibility with addition-cured polysiloxane chemistry that is used extensively in microfabrication. Regardless of the starch concentration, all of the developed bioelastomers have hydrophobic surfaces with lower friction coefficients and much less water uptake capacity than those of thermoplastic starch. The bioelastomers are biocompatible and are estimated to biodegrade in Mediterranean seawater within three to six years.

Regulatory Properties of ADP Glucose Pyrophosphorylase Are Required for Adjustment of Leaf Starch Synthesis in Different Photoperiods1[W][OPEN

PubMed Central

Mugford, Sam T.; Fernandez, Olivier; Brinton, Jemima; Flis, Anna; Krohn, Nicole; Encke, Beatrice; Feil, Regina; Sulpice, Ronan; Lunn, John E.; Stitt, Mark; Smith, Alison M.

2014-01-01

Arabidopsis (Arabidopsis thaliana) leaves synthesize starch faster in short days than in long days, but the mechanism that adjusts the rate of starch synthesis to daylength is unknown. To understand this mechanism, we first investigated whether adjustment occurs in mutants lacking components of the circadian clock or clock output pathways. Most mutants adjusted starch synthesis to daylength, but adjustment was compromised in plants lacking the GIGANTEA or FLAVIN-BINDING, KELCH REPEAT, F BOX1 components of the photoperiod-signaling pathway involved in flowering. We then examined whether the properties of the starch synthesis enzyme adenosine 5′-diphosphate-glucose pyrophosphorylase (AGPase) are important for adjustment of starch synthesis to daylength. Modulation of AGPase activity is known to bring about short-term adjustments of photosynthate partitioning between starch and sucrose (Suc) synthesis. We found that adjustment of starch synthesis to daylength was compromised in plants expressing a deregulated bacterial AGPase in place of the endogenous AGPase and in plants containing mutant forms of the endogenous AGPase with altered allosteric regulatory properties. We suggest that the rate of starch synthesis is in part determined by growth rate at the end of the preceding night. If growth at night is low, as in short days, there is a delay before growth recovers during the next day, leading to accumulation of Suc and stimulation of starch synthesis via activation of AGPase. If growth at night is fast, photosynthate is used for growth at the start of the day, Suc does not accumulate, and starch synthesis is not up-regulated. PMID:25293961

Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films

PubMed Central

2011-01-01

Background Cassava starch, the economically important agricultural commodity in Thailand, can readily be cast into films. However, the cassava starch film is brittle and weak, leading to inadequate mechanical properties. The properties of starch film can be improved by adding plasticizers and blending with the other biopolymers. Results Cassava starch (5%w/v) based films plasticized with glycerol (30 g/100 g starch) were characterized with respect to the effect of carboxymethyl cellulose (CMC) concentrations (0, 10, 20, 30 and 40%w/w total solid) and relative humidity (34 and 54%RH) on the mechanical properties of the films. Additionally, intermolecular interactions were determined by Fourier transform infrared spectroscopy (FT-IR), melting temperature by differential scanning calorimetry (DSC), and morphology by scanning electron microscopy (SEM). Water solubility of the films was also determined. Increasing concentration of CMC increased tensile strength, reduced elongation at break, and decreased water solubility of the blended films. FT-IR spectra indicated intermolecular interactions between cassava starch and CMC in blended films by shifting of carboxyl (C = O) and OH groups. DSC thermograms and SEM micrographs confirmed homogeneity of cassava starch-CMC films. Conclusion The addition of CMC to the cassava starch films increased tensile strength and reduced elongation at break of the blended films. This was ascribed to the good interaction between cassava starch and CMC. Cassava starch-CMC composite films have the potential to replace conventional packaging, and the films developed in this work are suggested to be suitable for low moisture food and pharmaceutical products. PMID:21306655

Direct fermentation of raw starch using a Kluyveromyces marxianus strain that expresses glucoamylase and alpha-amylase to produce ethanol.

PubMed

Wang, Rongliang; Wang, Dongmei; Gao, Xiaolian; Hong, Jiong

2014-01-01

Raw starch and raw cassava tuber powder were directly and efficiently fermented at elevated temperatures to produce ethanol using the thermotolerant yeast Kluyveromyces marxianus that expresses α-amylase from Aspergillus oryzae as well as α-amylase and glucoamylase from Debaryomyces occidentalis. Among the constructed K. marxianus strains, YRL 009 had the highest efficiency in direct starch fermentation. Raw starch from corn, potato, cassava, or wheat can be fermented at temperatures higher than 40°C. At the optimal fermentation temperature 42°C, YRL 009 produced 66.52 g/L ethanol from 200 g/L cassava starch, which was the highest production among the selected raw starches. This production increased to 79.75 g/L ethanol with a 78.3% theoretical yield (with all cassava starch were consumed) from raw cassava starch at higher initial cell densities. Fermentation was also carried out at 45 and 48°C. By using 200 g/L raw cassava starch, 137.11 and 87.71 g/L sugar were consumed with 55.36 and 32.16 g/L ethanol produced, respectively. Furthermore, this strain could directly ferment 200 g/L nonsterile raw cassava tuber powder (containing 178.52 g/L cassava starch) without additional nutritional supplements to produce 69.73 g/L ethanol by consuming 166.07 g/L sugar at 42°C. YRL 009, which has consolidated bioprocessing ability, is the best strain for fermenting starches at elevated temperatures that has been reported to date. © 2014 American Institute of Chemical Engineers.

Development of EMS-induced mutation population for amylose and resistant starch variation in bread wheat (Triticum aestivum) and identification of candidate genes responsible for amylose variation.

PubMed

Mishra, Ankita; Singh, Anuradha; Sharma, Monica; Kumar, Pankaj; Roy, Joy

2016-10-06

Starch is a major part of cereal grain. It comprises two glucose polymer fractions, amylose (AM) and amylopectin (AP), that make up about 25 and 75 % of total starch, respectively. The ratio of the two affects processing quality and digestibility of starch-based food products. Digestibility determines nutritional quality, as high amylose starch is considered a resistant or healthy starch (RS type 2) and is highly preferred for preventive measures against obesity and related health conditions. The topic of nutrition security is currently receiving much attention and consumer demand for food products with improved nutritional qualities has increased. In bread wheat (Triticum aestivum L.), variation in amylose content is narrow, hence its limited improvement. Therefore, it is necessary to produce wheat lines or populations showing wide variation in amylose/resistant starch content. In this study, a set of EMS-induced M4 mutant lines showing dynamic variation in amylose/resistant starch content were produced. Furthermore, two diverse mutant lines for amylose content were used to study quantitative expression patterns of 20 starch metabolic pathway genes and to identify candidate genes for amylose biosynthesis. A population comprising 101 EMS-induced mutation lines (M4 generation) was produced in a bread wheat (Triticum aestivum) variety. Two methods of amylose measurement in grain starch showed variation in amylose content ranging from ~3 to 76 % in the population. The method of in vitro digestion showed variation in resistant starch content from 1 to 41 %. One-way ANOVA analysis showed significant variation (p < 0.05) in amylose and resistant starch content within the population. A multiple comparison test (Dunnett's test) showed that significant variation in amylose and resistant starch content, with respect to the parent, was observed in about 89 and 38 % of the mutant lines, respectively. Expression pattern analysis of 20 starch metabolic pathway genes in two diverse mutant lines (low and high amylose mutants) showed higher expression of key genes of amylose biosynthesis (GBSSI and their isoforms) in the high amylose mutant line, in comparison to the parent. Higher expression of amylopectin biosynthesis (SBE) was observed in the low amylose mutant lines. An additional six candidate genes showed over-expression (BMY, SPA) and reduced-expression (SSIII, SBEI, SBEIII, ISA3) in the high amylose mutant line, indicating that other starch metabolic genes may also contribute to amylose biosynthesis. In this study a set of 101 EMS-induced mutant lines (M4 generation) showing variation in amylose and resistant starch content in seed were produced. This population serves as useful germplasm or pre-breeding material for genome-wide study and improvement of starch-based processing and nutrition quality in wheat. It is also useful for the study of the genetic and molecular basis of amylose/resistant starch variation in wheat. Furthermore, gene expression analysis of 20 starch metabolic genes in the two diverse mutant lines (low and high amylose mutants) indicates that in addition to key genes, several other genes (such as phosphorylases, isoamylases, and pullulanases) may also be involved in contributing to amylose/amylopectin biosynthesis.

Is there variation in resistant starch among high amylose rice varieties?

USDA-ARS?s Scientific Manuscript database

Resistant starch (RS) is the fraction of the starch and the products of starch degradation that resist digestion in the small intestines of healthy humans and is partially or entirely fermented in the colon by the microbiota. RS in food lowers postprandial glucose concentration and has potential in ...

Sustainability of low starch concentrations in sugarcane through short-term optimized amylase and long-term breeding strategies

USDA-ARS?s Scientific Manuscript database

Starch negatively affects the quantity and quality of raw sugar produced. Starch reduces crystallization and centrifugation rates, occludes into sucrose crystals, and impedes refinery decolorization processes. The problem of starch in sugarcane juice has been exacerbated by the widespread adoption...

Starch/fiber/poly(lactic acid) foam and compressed foam composites

USDA-ARS?s Scientific Manuscript database

Composites of starch, fiber, and poly(lactic acid) (PLA) were made using a foam substrate formed by dehydrating starch or starch/fiber gels. PLA was infiltrated into the dry foam to provide better moisture resistance. Foam composites were compressed into plastics using force ranging from 4-76MPa. Te...

Structure of Porous Starch Microcellular Foam Particles

USDA-ARS?s Scientific Manuscript database

A relatively new starch product with various novel applications is a porous microcellular foam. The foam product is made by dehydrating a starch hydrogel in a solvent such as ethanol and then removing the solvent to form a foam product. The process involves heating an aqueous slurry of starch (8% w/...

Properties of starch-polyglutamic acid (PGA) graft copolymer prepared by microwave irradiation - Fourier transform infrared spectroscopy (FTIR) and rheology studies

USDA-ARS?s Scientific Manuscript database

The rheological properties of waxy starch-'-polygutamic acid (PGA) graft copolymers were investigated. Grafting was confirmed by FTIR spectroscopy. The starch-PGA copolymers absorbed water and formed gels, which exhibited concentration-dependent viscoelastic solid properties. Higher starch-PGA conce...

40 CFR 406.100 - Applicability; description of the wheat starch and gluten subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... starch and gluten subcategory. 406.100 Section 406.100 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory. The...

21 CFR 184.1277 - Dextrin.

Code of Federal Regulations, 2013 CFR

2013-04-01

... incompletely hydrolyzed starch. It is prepared by dry heating corn, waxy maize, waxy milo, potato, arrowroot, wheat, rice, tapioca, or sago starches, or by dry heating the starches after: (1) Treatment with safe and suitable alkalis, acids, or pH control agents and (2) drying the acid or alkali treated starch. (b...

40 CFR 406.100 - Applicability; description of the wheat starch and gluten subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... starch and gluten subcategory. 406.100 Section 406.100 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory. The...

40 CFR 406.100 - Applicability; description of the wheat starch and gluten subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... starch and gluten subcategory. 406.100 Section 406.100 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory. The...

21 CFR 184.1277 - Dextrin.

Code of Federal Regulations, 2012 CFR

2012-04-01

... incompletely hydrolyzed starch. It is prepared by dry heating corn, waxy maize, waxy milo, potato, arrowroot, wheat, rice, tapioca, or sago starches, or by dry heating the starches after: (1) Treatment with safe and suitable alkalis, acids, or pH control agents and (2) drying the acid or alkali treated starch. (b...

Two Distinct Waxy Alleles Impact the Granule-Bound Starch Synthase in Sorghum

USDA-ARS?s Scientific Manuscript database

The granule-bound starch synthase (GBSS) is the enzyme responsible for amylose synthesis in starch granules. Loss of GBSS activity results in starch granules containing mostly amylopectin and little or no amylose, a phenotype described as waxy. Previously, two phenotypic classes of waxy alleles we...

Analytical evaluation of current starch methods used in the international sugar industry: Part I

USDA-ARS?s Scientific Manuscript database

Several analytical starch methods currently exist in the international sugar industry that are used to prevent or mitigate starch-related processing challenges as well as assess the quality of traded end-products. These methods use simple iodometric chemistry, mostly potato starch standards, and uti...

Maltase-glucoamylase: Mucosal regulator of prandial starch glucogenesis and complimentary hepatic gluconeogenesis of mice

USDA-ARS?s Scientific Manuscript database

In previous studies we have shown that maltase-glucoamylase (Mgam) is required for efficient starch digestion and insulin response to starch feeding. It was hypothesized that the slower rate of starch digestion by residual sucrase-isomaltase (Si) maltase failed to regulate gluconeogenesis. Here, rat...

Effect of temperature and selected sugars on dilute solution properties of two hairless canary seed starches compared with wheat starch.

PubMed

Heydari, Ali; Razavi, Seyed Mohammad Ali; Irani, Mahdi

2018-03-01

In this paper, influence of temperature (25, 35, 45 and 55°C) and sugars (sucrose and lactose) at different concentrations (0, 5, 10 and 15%) on some molecular parameters of starches from two canary seed varieties (C05041 and CDC Maria) in the dilute regime were investigated in comparison to wheat starch (WS). The results indicated that the intrinsic viscosity ([η]) values of C05041, CDC Maria and WS samples were 1.42, 1.46 and 1.70dl/g at 25°C, respectively. Intrinsic viscosity of selected starches decreased with an increase in temperature, but the effect of high temperatures were somewhat unnoticeable. By increasing the sugar concentration, intrinsic viscosity of each starch solution significantly decreased in comparison with the value determined for sugar free solution. Lactose had more pronounced effect on the intrinsic viscosity reduction of CDC Maria starch and WS at 25°C and 35°C compared with sucrose (P<0.05). But at 55°C, the effect of increasing sucrose on decreasing of [η] of CDC Maria and WS samples were more considerable. The shape factor of starch samples at 25°C were spherical, but increasing temperature from 25°C to 55°C, CSSs and WS samples took an ellipsoidal shape. The interaction between starches and solvent/cosolutes is the predominant factors determining their functional properties in food systems. One of the aspects can help to understand the characteristic of biopolymers such as starches is determination of their dilute solution properties as a function of common additives which are used in food systems. As a matter of fact, dilute solution properties can help to understand the potential applications of biopolymers in food and non-food application. Attentively, dilute solution properties would give some priceless information about molecular properties, biopolymer behavior and its interaction with copolymers. For instance, intrinsic viscosity provides deep insight into fundamental properties of the solute and its interaction with the solvent and/or cosolutes, conformation of flexible chains. There are many studies which investigated the effect of different parameters such as temperature, salts and sugars on dilute solution properties of hydrocolloids, especially gums. Regrettably, few researches scrutinized the influence of various cosolutes on dilute solution properties of starch. Then in this paper, we studied the dilute solution properties of starches from two canary seed varieties (C05041 and CDC Maria), as a new potential source of starch, (CSSs), in comparison to wheat starch at different experimental conditions (temperatures and sugars at different concentrations) in order to shed light on its behavior in real system in comparison to wheat starch. Because of the unique properties of wheat starch, comparison of canary seed starch with wheat starch in dilute regime can help to having better vision of this new starch source. Overall, the intrinsic viscosity, coil dimensions (R coil and V coil ), swollen specific volume, shape function, and hydration parameter of selected starches were determined affected by temperature and sugars concentration treatments. The importance of these results will be cleared when taking into account the influence of crucial additives generally used in food systems, for instance, different sugars and/or frequent processing parameters such as temperature on rheological and functional properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Study on the preparation process of cross-linked porous cassava starch

NASA Astrophysics Data System (ADS)

Yin, Xiulian; You, Qinghong; Wan, Miaomiao; Zhang, Xuejuan; Dai, Chunhua

2017-04-01

Using cassava starch as raw material, preparation process of porous cross-linked cassava starch was studied. Using TSTP as cross-linking agents, Orthogonal design was applied for the optimization of cross-linked porous starch preparation process. The results showed that the opitmal conditions of cross-linked porous cassava starch were as follows: reaction temperature 45°C, reaction time 20 h, 1% of the amount of the enzyme, the enzyme ratio of 1:5, pH 5.50, substrate concentration of 40%.

Biodegradability and mechanical properties of poly-([beta]-hyroxybutyrate-Co-[beta]-hydroxyvalerate)-starch blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramsay, B.A.; Langlade, V.; Carreau, P.J.

1993-04-01

PHAs, biodegradable thermoplastics, are a promising option to synthetic resins such as polyethylene, in combination with starch, to produce biodegradable plastics. This paper describes the mechanical properties and biodegradability of blends of wheat starch and P(HB-co-HV). The results indicate that the addition of starch to P(HB-co-HV) not only reduces the cost but also leads to a completely biodegradable material whose degradation can be tailored by adjusting the starch/PHA ratio. 15 refs., 3 figs., 1 tab.

Towards a more versatile alpha-glucan biosynthesis in plants.

PubMed

Kok-Jacon, Géraldine A; Ji, Qin; Vincken, Jean-Paul; Visser, Richard G F

2003-07-01

Starch is an important storage polysaccharide in many plants. It is composed of densely packed alpha-glucans, consisting of 1,4- and 1,4,6-linked glucose residues. The starch polymers are used in many industrial applications. The biosynthetic machinery for assembling the granule has been manipulated in many different ways to gain insight into the process of starch biosynthesis and to engineer starches with improved functionalities. With respect to the latter, two generic technologies with great potential have been developed: (i) introduction of new linkage types in starch polymers (1,3- and 1,6-linkages), and (ii) engineering granule-boundness. The toolbox to engineer this new generation of starch polymers is discussed.

Evaluation of tensile properties and water absortion of cassava starch film

NASA Astrophysics Data System (ADS)

Walster, R. Justin; Rozyanty, A. R.; Kahar, A. W. M.; Musa, L.; Shahnaz, S. B. S.

2017-09-01

Casava Starch film was prepared by casting method with different percentage of glycerol (0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%) as plasticizer. The effect of glycerol content in starch film on mechanical and water absorption properties was studied. Results shows that the increase of glycerol content in cassava starch film had decrease the tensile strength, tensile modulus and increase the elongation of break properties. The result of water absorbency tended to increase for starch film with higher percentage of glycerol content. The incorporation of glycerol in cassava starch film had increase the water absorption ability due to increase of hydroxyl content contributed by glycerol.

Leaf starch degradation comes out of the shadows.

PubMed

Lloyd, James R; Kossmann, Jens; Ritte, Gerhard

2005-03-01

During the day, plants accumulate starch in their leaves as an energy source for the coming night. Based on recent findings, the prevailing view of how the transitory starch is remobilized needs considerable revision. Analyses of transgenic and mutant plants demonstrate that plastidic glucan phosphorylase is not required for normal starch breakdown and cast doubt on the presumed essential role of alpha-amylase but do show that beta-amylase is important. Repression of the activity of a plastidic beta-amylase, the export of its product (maltose) or further metabolism of maltose by a newly identified transglucosidase impairs starch degradation. Breakdown of particulate starch also depends on the activity of glucan-water dikinase, which phosphorylates glucosyl residues within the polymer.

Effect of tea products on the in vitro enzymatic digestibility of starch.

PubMed

Zhang, Haihua; Jiang, Yulan; Pan, Junxian; Lv, Yangjun; Liu, Jun; Zhang, Shikang; Zhu, Yuejin

2018-03-15

The importance of postprandial hyperglycemia in the treatment of diabetes has been recognized recently. Tea products, such as tea polyphenols (TP), epigallocatechin gallate (EGCG), matcha, and instant tea, were chosen as constituents of tea-flour food, aimed at regulating the release of glucose from starchy foods in the postprandial period. Six starches were chosen for internal composition analysis and hydrolysis studies in vitro. Corn starch, wheat starch, and lily root flour appeared to have higher resistant starch content, slower digestion profiles, and lower kinetic constants, implying sustained release of glucose in the gastrointestinal tract. The effect of tea products on starch digestion was determined in order to get a desired formulation of dietary product for patients with hyperglycemia. Compared with macha and instant tea, TP and EGCG exerted greater inhibition of amylase and amyloglucosidase, especially for corn starch with 0.5% TP or 0.5% EGCG. Copyright © 2017 Elsevier Ltd. All rights reserved.

Resistant starch: a functional food that prevents DNA damage and chemical carcinogenesis.

PubMed

Navarro, S D; Mauro, M O; Pesarini, J R; Ogo, F M; Oliveira, R J

2015-03-06

Resistant starch is formed from starch and its degradation products and is not digested or absorbed in the intestine; thus, it is characterized as a fiber. Because fiber intake is associated with the prevention of DNA damage and cancer, the potential antigenotoxic, antimutagenic, and anticarcinogenic capabilities of resistant starch from green banana flour were evaluated. Animals were treated with 1,2-dimethylhydrazine and their diet was supplemented with 10% green banana flour according to the following resistant starch protocols: pretreatment, simultaneous treatment, post-treatment, and pre + continuous treatment. The results demonstrated that resistant starch is not genotoxic, mutagenic, or carcinogenic. The results suggest that resistant starch acts through desmutagenesis and bio-antimutagenesis, as well as by reducing aberrant crypt foci, thereby improving disease prognosis. These findings imply that green banana flour has therapeutic properties that should be explored for human dietary applications.

Modification of wheat starch with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures. II. Chemical and physical properties.

PubMed

Ačkar, Durđica; Subarić, Drago; Babić, Jurislav; Miličević, Borislav; Jozinović, Antun

2014-08-01

The aim of this research was to investigate the influence of modification with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures on chemical and physical properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetanhydride and azelaic acid and acetanhydride in 4, 6 and 8% (w/w). Total starch content, resistant starch content, degree of modification, changes in FT-IR spectra, colour, gel texture and freeze-thaw stability were determined. Results showed that resistant starch content increased by both investigated modifications, and degree of modification increased proportionally to amount of reagents used. FT-IR analysis of modified starches showed peak around 1,740 cm(-1), characteristic for carbonyl group of ester. Total colour difference caused by modifications was detectable by trained people. Adhesiveness significantly increased, while freeze-thaw stability decreased by both investigated modifications.

Effect of resistant and digestible rice starches on human cytokine and lactate metabolic networks in serum.

PubMed

Wang, Huisong; Pang, Guangchang

2017-05-01

Resistant starch generated after treating ordinary starch is of great significance to human health in the countries with overnutrition. However, its functional evaluation in the human body has been rarely reported. By determining the lactate metabolic flux, 12 serum enzymes expression level and 38 serum cytokines in healthy volunteers, the variation in cytokine network and lactate metabolic network in serum were investigated to compare the mechanism of the physiological effects between the two starches. The results indicated that compared with digestible starch, resistant starch had anti-inflammatory effects, increased anabolism, and decreased catabolism. Further, the intercellular communication networks including cytokine and lactate metabolic networks were mapped out. The relationship suggested that resistant starch might affect and control the secretion of cytokines to regulate lactate metabolic network in the body, promoting the development of immunometabolism. Copyright © 2017 Elsevier Ltd. All rights reserved.

Water sorption behavior and swelling characteristics of starches subjected to dielectric heating.

PubMed

Szepes, Anikó; Szabó-Révész, Piroska; Mohnicke, Mandy

2007-01-01

The aim of this study was to investigate the effects of microwave irradiation and storage on the moisture content, adsorption behavior and swelling properties of potato (B-type) and maize starches (A-type). Volumetric heating resulted in reversible moisture loss from both types of samples. The crystallinity of potato starch was decreased, whereas its water retention capacity and swelling power were increased irreversibly, and its swelling capacity was increased reversibly by the thermal process applied. The corresponding parameters of maize starch were not influenced significantly by dielectric heating; this may be related to its special structure resulting in the thermal resistance of this polymer. Our results allow the conclusion that microwave irradiation offers an appropriate and selective alternative for the physicochemical modification of potato starch. In consequence of its low susceptibility to thermal processes, maize starch may be used for the microwave drying of pharmaceutical formulations containing starch.

Characterization of superabsorbent hydrogel based on epichlorohydrin crosslink and carboxymethyl functionalization of cassava starch

NASA Astrophysics Data System (ADS)

Muharam, S.; Yuningsih, L. M.; Sumitra, M. R.

2017-07-01

Superabsorbent hydrogel was prepared by epichlorohydrin crosslink of cassava starch. Their swelling improved with added carboxymethyl group on the starch-epichlorohydrin structure. The structure and properties of starch-epichlorohydrin-carboxymethyl hydrogel were measured by SEM, FTIR, water and physiological solution absorption test and water retention test. The result showed that hydrogel displayed macroporous with heterogenous distribution and irregular surface was formed by epichlorohydrin and carboxymethyl bond in the structure of hydrogel. It was confirmed also by the FTIR spectra. The swelling ratio of starch-epichlorohydrin hydrogel to the water is 518 % and increased to 1,028.5 % with carboxymethyl addition on the structure. The best influence of the physiological solution to the swelling ratio of starch-epichlorohydrin-carboxymethyl hydrogel is urea solution. The water retention of starch-epichlorohydrin-carboxymethyl hydrogel in NaCl solution is better than in CaCl2 solution.

Physicochemical and functional properties of gamma irradiated buckwheat and potato starch

NASA Astrophysics Data System (ADS)

Verma, Ruchi; Jan, Shumaila; Rani, Savita; Jan, Kulsum; Swer, Tanya L.; Prakash, Kumar S.; Dar, M. Z.; Bashir, Khalid

2018-03-01

Starches isolated from buckwheat and potato were subject to different doses of irradiation at 0, 5, 10, 15 and 20 kGy. Native and irradiated starch samples were evaluated for their physicochemical and functional properties to assess the effect of gamma irradiation. Apparent amylose content decreased significantly from 26.84% to 22.12% and 27.01 to 16.11% for buckwheat and potato starch respectively as the dose increased. A significant decrease was observed in pH, swelling power and syneresis as the dose increased for both buckwheat and potato starch. pH decreased from 5.20 to 3.81 and 5.81 to 3.95 for buckwheat and potato starch, respectively. Carboxyl content, freeze thaw stability, water and oil absorption capacity and transmittance showed increasing trend with increasing irradiation dose. Carboxyl content increased from 0% to 0.23% and 0-0.22% for buckwheat and potato starch, respectively.

A comparative study on starch digestibility, glycemic index and resistant starch of pigmented ('Njavara' and 'Jyothi') and a non-pigmented ('IR 64') rice varieties.

PubMed

Deepa, G; Singh, Vasudeva; Naidu, K Akhilender

2010-12-01

In vitro starch digestibility and glycemic indices of three rice varieties- 'Njavara', 'Jyothi' (pigmented rice verities) and 'IR 64' (non-pigmented rice) with similar amylose content were studied. Starch digestibility studies showed differences in glycemic response in three types of rice. The rate of starch hydrolysis was maximum (67.3%) in 'Njavara' rice compared to other two rice varieties. 'Njavara' exhibited the lowest kinetic constant (k) indicating inherent resistance to enzymatic hydrolysis. The glycemic load (GL) and glycemic index (GI) of 'Njavara' were similar to 'Jyothi' and 'IR 64'. Resistant starch content was high in pigmented rice varieties compared to 'IR 64'. The resistant starch content of dehusked and cooked rice increased with the storage time at refrigeration temperature (4°C). 'Njavara' is an easily digestible rice and can be used for baby and geriatric foods.

Process development of starch hydrolysis using mixing characteristics of Taylor vortices.

PubMed

Masuda, Hayato; Horie, Takafumi; Hubacz, Robert; Ohmura, Naoto; Shimoyamada, Makoto

2017-04-01

In food industries, enzymatic starch hydrolysis is an important process that consists of two steps: gelatinization and saccharification. One of the major difficulties in designing the starch hydrolysis process is the sharp change in its rheological properties. In this study, Taylor-Couette flow reactor was applied to continuous starch hydrolysis process. The concentration of reducing sugar produced via enzymatic hydrolysis was evaluated by varying operational variables: rotational speed of the inner cylinder, axial velocity (reaction time), amount of enzyme, and initial starch content in the slurry. When Taylor vortices were formed in the annular space, efficient hydrolysis occurred because Taylor vortices improved the mixing of gelatinized starch with enzyme. Furthermore, a modified inner cylinder was proposed, and its mixing performance was numerically investigated. The modified inner cylinder showed higher potential for enhanced mixing of gelatinized starch and the enzyme than the conventional cylinder.

Effect of Agitation in Alkalization Process on the Characteristics of Sodium Carboxymethyl Sago and Cassava Starches

NASA Astrophysics Data System (ADS)

Titi, C. S.; Fachrudin, R.; Ruriani, E.; Yuliasih, I.

2018-05-01

Sodium carboxymethyl starch (Sodium CMS) is a modified starch prepared by two successive processes, alkalization and etherification. Alkalization will change the activated hydroxyl group of starch to more reactive alkoxide (St-O-), and then carboxymethyl group will substitute the hydroxyl group into sodium CMS. This research investigated the effect of agitation (1000 rpm of stirring and 4000 rpm of homogenization) in alkalization process to the modification of native starch into sodium CMS. Cassava and sago starches were mixed with sodium hydroxide (1.8 and 1.9 moles per mole anhydrous glucose units). The combination of NaOH and homogenizing gave the highest degrees of substitution for cassava (DS 0.73) and sago (DS 0.55) starches. The sodium CMS characteristics (paste clarity, water and oil absorption capacities, solubility, swelling power) were a function of mixing method but not on the amount of NaOH used.

Plasma modification of starch.

PubMed

Zhu, Fan

2017-10-01

Plasma is a medium of unbound negative and positive particles with the overall electrical charge being roughly zero. Non-thermal plasma processing is an emerging green technology with great potential to improve the quality and microbial safety of various food materials. Starch is a major component of many food products and is an important ingredient for food and other industries. There has been increasing interest in utilizing plasma to modify the functionalities of starch through interactions with reactive species. This mini-review summarises the impact of plasma on composition, chemical and granular structures, physicochemical properties, and uses of starch. Structure-function relationships of starch components as affected by plasma modifications are discussed. Effect of plasma on the properties of wheat flour, which is a typical example of starch based complex food systems, is also reviewed. Future research directions on how to better utilise plasma to improve the functionalities of starch are suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multi-scale structure, pasting and digestibility of heat moisture treated red adzuki bean starch.

PubMed

Wang, Hongwei; Wang, Zhaoyuan; Li, Xiaoxi; Chen, Ling; Zhang, Binjia

2017-09-01

The pasting and digestibility of a red adzuki bean starch were simultaneously modulated by heat-moisture treatment (HMT) through altering the multi-scale structure. HMT, especially at high moisture content, could disrupt the granule integrity, semicrystalline lamellae, molecular order (crystallites) and molecular chains. Also, certain rearrangement of starch molecules occurred to form ordered structures with increased thermal stability as shown by DSC. This concomitant disordering and reassembly in the multi-scale structure converted the fractions of resistant starch (RS) and rapidly digestible starch (RDS) into that of slowly digestible starch (SDS). Furthermore, the emergence of thermally-stable orders increased the pasting temperature but suppressed the swelling of granules during heating. Hence, HMT-modified red adzuki starch may serve as a potential thickener/gelling agent with slow digestion rate for various foods. Copyright © 2017. Published by Elsevier B.V.

Effects of carbohydrate/protein ratio on the microstructure and the barrier and sorption properties of wheat starch-whey protein blend edible films.

PubMed

Basiak, Ewelina; Lenart, Andrzej; Debeaufort, Frédéric

2017-02-01

Starch and whey protein isolate and their mixtures were used for making edible films. Moisture sorption isotherms, water vapour permeability, sorption of aroma compounds, microstructure, water contact angle and surface properties were investigated. With increasing protein content, the microstructure changes became more homogeneous. The water vapour permeability increases with both the humidity gradient and the starch content. For all films, the hygroscopicity increases with starch content. Surface properties change according to the starch/whey protein ratio and are mainly related to the polar component of the surface tension. Films composed of 80% starch and 20% whey proteins have more hydrophobic surfaces than the other films due to specific interactions. The effect of carbohydrate/protein ratio significantly influences the microstructure, the surface wettability and the barrier properties of wheat starch-whey protein blend films. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Starch granule initiation is controlled by a heteromultimeric isoamylase in potato tubers

PubMed Central

Bustos, Regla; Fahy, Brendan; Hylton, Christopher M.; Seale, Robert; Nebane, N. Miranda; Edwards, Anne; Martin, Cathie; Smith, Alison M.

2004-01-01

Starch granule initiation is not understood, but recent evidence implicates a starch debranching enzyme, isoamylase, in the control of this process. Potato tubers contain isoamylase activity attributable to a heteromultimeric protein containing Stisa1 and Stisa2, the products of two of the three isoamylase genes of potato. To discover whether this enzyme is involved in starch granule initiation, activity was reduced by expression of antisense RNA for Stisa1 or Stisa2. Transgenic tubers accumulated a small amount of a soluble glucan, similar in structure to the phytoglycogen of cereal, Arabidopsis, and Chlamydomonas mutants lacking isoamylase. The major effect, however, was on the number of starch granules. Transgenic tubers accumulated large numbers of tiny granules not seen in normal tubers. These data indicate that the heteromultimeric isoamylase functions during starch synthesis to suppress the initiation of glucan molecules in the plastid stroma that would otherwise crystallize to nucleate new starch granules. PMID:14766984

Structure of New Zealand sweetpotato starch.

PubMed

Zhu, Fan; Xie, Qian

2018-05-15

New Zealand sweetpotatoes (kumara) (Ipomoea batatas) represent unique genetic resources for sweetpotato diversity, though they are much under-studied. In this study, 7 New Zealand sweetpotato varieties with commercial significance were collected for the characterization of the molecular and granular structure of the starches. In particular, the internal molecular structure of the amylopectins was detailed by chromatographic and enzymatic techniques. Maize and potato starches with normal amylose contents, which are among the most important commercial starch sources, were employed for comparison. The results revealed a degree of diversity in amylose composition, unit and internal chain composition, granule size distribution, and degree of crystallinity among the 7 sweetpotato starches. All the sweetpotato starches showed C A -type polymorph. The sweetpotato amylopectins have intermediate amounts of both short and long internal unit chains among amylopectins of different botanical sources. The differences in the structure of sweetpotato starches suggest differences in physicochemical properties. Copyright © 2018 Elsevier Ltd. All rights reserved.

Ultra-small and anionic starch nanospheres: formation and vitro thrombolytic behavior study.

PubMed

Huang, Yinjuan; Ding, Shenglong; Liu, Mingzhu; Gao, Chunmei; Yang, Jinlong; Zhang, Xinjie; Ding, Bin

2013-07-25

This paper is considered as the first report on the investigation of nattokinase (NK) release from anionic starch nanospheres. The ultra-small and anionic starch nanospheres were prepared by the method of reverse micro-emulsion crosslinking in this work. Starch nanospheres were characterized through Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). Effects of preparation conditions on particle size were studied. The cytotoxicity, biodegradable and vitro thrombolytic behaviors of nattokinase (NK) loaded anionic starch nanospheres were also studied. The results showed that the anionic starch nanospheres are non-toxic, biocompatible and biodegradable. Moreover, the anionic starch nanospheres can protect NK from fast biodegradation hence prolongs the circulation in vivo and can reduce the risk of acute hemorrhage complication by decreasing the thrombolysis rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

Determination of dietary starch in animal feeds and pet food by an enzymatic-colorimetric method: collaborative study

USDA-ARS?s Scientific Manuscript database

Starch, glycogen, maltooligosaccharides, and other alpha-1,4- and alpha-1,6-linked glucose carbohydrates exclusive of resistant starch are collectively termed "dietary starch." This nutritionally important fraction is increasingly measured for use in diet formulation for animals, as it can have posi...

Branch pattern of starch internal structure influences the glucogenesis by mucosal Nt-maltase-glucoamylase

USDA-ARS?s Scientific Manuscript database

To produce sufficient amounts of glucose from food starch, both alpha-amylase and mucosal alpha-glucosidases are required. We found previously that the digestion rate of starch is influenced by its susceptibility to mucosal alpha-glucosidases. In the present study, six starches and one glycogen were...

Pasting and extrusion properties of mixed carbohydrates and whey protein isolate matrices

USDA-ARS?s Scientific Manuscript database

Mixed systems of whey protein isolate (WPI) or texturized WPI (tWPI) and different starches may form weak or strong gel pastes or rigid matrices depending on interactions. The paste viscoelasticity of starches from amioca, barley, corn starch, Hylon VII, plantain, and pea starch, mixed with whey pro...

Effect of orientation on the morphology and mechanical properties of PLA/starch composite filaments

USDA-ARS?s Scientific Manuscript database

PLA/starch fibers were produced by twin screw extrusion of PLA with granular or gelatinized starch/glycerol followed by drawing through a set of winders with an intermediate oven. At 30% starch, fibers drawn 2-5x were highly flexible (elongation 20-100%) while undrawn filaments were brittle (elonga...

21 CFR 168.120 - Glucose sirup.

Code of Federal Regulations, 2014 CFR

2014-04-01

... saccharides obtained from edible starch. (b) The food shall meet the following specifications: (1) The total... from a specific type of starch, the name may alternatively be “___ sirup”, the blank to be filled in with the name of the starch. For example, “Corn sirup”, “Wheat sirup”, “Tapioca sirup”. When the starch...

Amylose Content in Tuber Starch of Potato Cultivars

USDA-ARS?s Scientific Manuscript database

Potato tuber is mostly water and starch. Approximately 20% of fresh tuber weight is the starch and the remainder is water. Most of the starch in the tuber, approximately 75%, is amylopectin and 25% amylose, but can vary depending on the cultivar. A total of 162 American (85) and foreign (77) potato ...

Position of modifying groups on starch chains of octenylsuccinic anhydride-modified waxy maize starch

USDA-ARS?s Scientific Manuscript database

Octenylsuccinic anhydride (OSA)-modified starches with degree of substitution of 0.018 (OS-S-L) and 0.092 (OS-S-H) were prepared from granular native waxy maize starch in an aqueous slurry system. The substitution distribution of OS groups was investigated by enzyme hydrolysis followed by chromatogr...

Sorghum starch properties as affected by growing season, hybrid, and kernel maturity

USDA-ARS?s Scientific Manuscript database

Starch is a widely used component in the food, feed, and biofuel industries. Critical components in the functionality of a starch in a food or industrial system are the thermal properties. The objective of this study was to evaluate the physical and chemical changes that occur in sorghum starch du...

Influence of a diet rich in resistant starch on the degradation of non-starch polysaccharides in the large intestine of pigs.

PubMed

Jonathan, Melliana C; Haenen, Daniëlle; Souza da Silva, Carol; Bosch, Guido; Schols, Henk A; Gruppen, Harry

2013-03-01

To investigate the effect of resistant starch to the degradation of other non-starch polysaccharides (NSPs) in the large intestine of pigs, two groups of pigs were fed either a diet containing digestible starch (DS) or a diet containing resistant starch (RS). Both diets contained NSPs from wheat and barley. Digesta from different parts of the large intestine were collected and analysed for sugar composition and carbohydrate-degrading-enzyme activities. Resistant starch, as well as β-glucans and soluble arabinoxylan, was utilised mainly in the caecum. The utilisation of β-glucans and soluble arabinoxylan in the caecum was higher in DS-fed pigs than in RS-fed pigs. Analyses on carbohydrate-degrading-enzyme activities demonstrated that microbial enzyme production was stimulated according to the diet composition, and the enzyme profile throughout the large intestine of RS-fed pigs indicated that the presence of resistant starch shifted the utilisation of NSPs to more distal parts of the colon. Copyright © 2012 Elsevier Ltd. All rights reserved.

Optimisation of the reaction conditions for the production of cross-linked starch with high resistant starch content.

PubMed

Kahraman, Kevser; Koksel, Hamit; Ng, Perry K W

2015-05-01

The optimum reaction conditions (temperature and pH) for the preparation of cross-linked (CL) corn and wheat starches with maximum resistant starch (RS) content were investigated by using response surface methodology (RSM). According to the preliminary results, five levels were selected for reaction temperature (38-70 °C) and pH (10-12) in the main study. RS contents of the CL corn and wheat starch samples increased with increasing temperature and pH, and pH had a greater influence on RS content than had temperature. The maximum RS content (with a maximum p value of 0.4%) was obtained in wheat starch cross-linked at 38 °C and pH 12. In the case of CL corn starch, the optimum condition was 70 °C and pH 12. CL corn and wheat starch samples were also produced separately under the optimum conditions and their RS contents were 80.4% and 83.9%, respectively. These results were also in agreement with the values predicted by RSM. Copyright © 2014 Elsevier Ltd. All rights reserved.

Incorporation of dietary fibre-rich oyster mushroom (Pleurotus sajor-caju) powder improves postprandial glycaemic response by interfering with starch granule structure and starch digestibility of biscuit.

PubMed

Ng, Sze Han; Robert, Sathyasurya Daniel; Wan Ahmad, Wan Amir Nizam; Wan Ishak, Wan Rosli

2017-07-15

The purpose of this study was to determine the effects of Pleurotus sajor-caju (PSC) powder addition at 0, 4, 8 and 12% levels on the nutritional values, pasting properties, thermal characteristics, microstructure, in vitro starch digestibility, in vivo glycaemic index (GI) and sensorial properties of biscuits. Elevated incorporation levels of PSC powder increased the dietary fibre (DF) content and reduced the pasting viscosities and starch gelatinisation enthalpy value of biscuits. The addition of DF-rich PSC powder also interfered with the integrity of the starch granules by reducing the sizes and inducing the uneven spherical shapes of the starch granules, which, in turn, resulted in reduced starch susceptibility to digestive enzymes. The restriction starch hydrolysis rate markedly reduced the GI of biscuits. The incorporation of 8% PSC powder in biscuits (GI=49) could be an effective way of developing a nutritious and low-GI biscuit without jeopardizing its desirable sensorial properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reduction of acrylamide content in bread crust by starch coating.

PubMed

Liu, Jie; Liu, Xiaojie; Man, Yong; Liu, Yawei

2018-01-01

A technique of starch coating to reduce acrylamide content in bread crust was proposed. Bread was prepared in accordance with a conventional procedure and corn or potato starch coating was brushed on the surface of the fermented dough prior to baking. Corn starch coating caused a decrease in acrylamide of 66.7% and 77.1% for the outer and inner crust, respectively. The decrease caused by the potato starch coating was 68.4% and 77.4%, respectively. Starch coating reduced asparagine content significantly (43.4-82.9%; P < 0.01)in both the outer and inner crust. A lower temperature (difference of 10-20 °C) in combination with a higher moisture content (maximum difference of 8%) of bread crust were a result of starch coating, which effectively shortened the time span (4-8 min) over which acrylamide could form and accumulate. The present study demonstrates that starch coating could be a simple, effective and practical application for reducing acrylamide levels in bread crust without changing the texture and crust color of bread. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Preparation and characterization of potato starch-thymol dispersion and film as potential antioxidant and antibacterial materials.

PubMed

Davoodi, Mina; Kavoosi, Gholamreza; Shakeri, Raheleh

2017-11-01

The antioxidant/antimicrobial capacity and physical properties of potato starch dispersions enriched with polysorbate-thymol micelle were investigated. Results showed that potato starch have radical scavenging and antibacterial activities only in the presence of polysorbate-thymol but with lower level than polysorbate-thymol alone. The decrease in the antioxidant and antibacterial activities may be attributed to the encapsulation of thymol in the starch chain. Polysorbate-thymol caused a decrease in the particle size and viscosity and an increase in the zeta potential of the starch dispersions. Futhermore, polysorbate-thymol leads to a decrease in the tensile strength, rigidity and swelling, and an increase in the flexibility, solubility and water vapour permeability of the starch films. Atomic force microscopy revealed polysorbate-thymol micelles in the film matrix enclosed by polysaccharide crystal. Scanning electron microscope analysis indicated that polysorbate-thymol caused a coarse film microstructure with the distributed crack in the film matrix. Based on the results, the antioxidant and antibacterial activities of the starch-polysorbate-thymol make starch film suitable for food packaging and preservation. Copyright © 2017 Elsevier B.V. All rights reserved.

Rheological and biochemical properties of Solanum lycocarpum starch.

PubMed

Di-Medeiros, Maria Carolina B; Pascoal, Aline M; Batista, Karla A; Bassinello, Priscila Z; Lião, Luciano M; Leles, Maria Inês G; Fernandes, Kátia F

2014-04-15

This study was conducted to evaluate the rheological and physicochemical properties of Solanum lycocarpum starch. The thermogravimetric analysis of S. lycocarpum starch showed a typical three-step weight loss pattern. Microscopy revealed significant changes in the granule morphology after hydrothermal treatment. Samples hydrothermally treated at 50°C for 10 min lost 52% of their crystallinity, which was recovered after storage for 7 days at 4°C. However, samples hydrothermally treated at 65°C were totally amorphous. This treatment was sufficient to completely disrupt the starch granule, as evidenced by the absence of an endothermic peak in the DSC thermogram. The RVA of S. lycocarpum starch revealed 4440.7cP peak viscosity, 2660.5cP breakdown viscosity, 2414.1cP final viscosity, 834.3cP setback viscosity, and a pasting temperature of 49.6°C. The low content of resistant starch (10.25%) and high content of digestible starch (89.78%) in S. lycocarpum suggest that this starch may be a good source for the production of hydrolysates, such as glucose syrup and its derivatives. Copyright © 2014 Elsevier Ltd. All rights reserved.

Differential effects of genetically distinct mechanisms of elevating amylose on barley starch characteristics.

PubMed

Regina, Ahmed; Blazek, Jaroslav; Gilbert, Elliot; Flanagan, Bernadine M; Gidley, Michael J; Cavanagh, Colin; Ral, Jean-Philippe; Larroque, Oscar; Bird, Anthony R; Li, Zhongyi; Morell, Matthew K

2012-07-01

The relationships between starch structure and functionality are important in underpinning the industrial and nutritional utilisation of starches. In this work, the relationships between the biosynthesis, structure, molecular organisation and functionality have been examined using a series of defined genotypes in barley with low (<20%), standard (20-30%), elevated (30-50%) and high (>50%) amylose starches. A range of techniques have been employed to determine starch physical features, higher order structure and functionality. The two genetic mechanisms for generating high amylose contents (down-regulation of branching enzymes and starch synthases, respectively) yielded starches with very different amylopectin structures but similar gelatinisation and viscosity properties driven by reduced granular order and increased amylose content. Principal components analysis (PCA) was used to elucidate the relationships between genotypes and starch molecular structure and functionality. Parameters associated with granule order (PC1) accounted for a large percentage of the variance (57%) and were closely related to amylose content. Parameters associated with amylopectin fine structure accounted for 18% of the variance but were less closely aligned to functionality parameters. Copyright © 2012 Elsevier Ltd. All rights reserved.

Improvement on the freeze-thaw stability of corn starch gel by the polysaccharide from leaves of Corchorus olitorius L.

PubMed

Yamazaki, Eiji; Sago, Toru; Kasubuchi, Yoshiaki; Imamura, Kazuhito; Matsuoka, Toshio; Kurita, Osamu; Nambu, Hironobu; Matsumura, Yasuki

2013-04-15

Effect of the polysaccharide from leaves of Corchorus olitorius L. (PLC) on the freeze-thaw (FT) stability of corn starch gel was studied. PLC was incorporated into the starch gel at 0.7% and total solid was adjusted to 6.0%. The syneresis was measured by the centrifugal-filtration method and, as a result, addition of PLC reduced effectively the syneresis of the starch gel even after 5 FT cycles, which was less than one third that of the normal starch gel. The rheological changes of the starch/PLC gel during the FT treatments were evaluated while the gel remained on the rheometer plate. The starch/PLC gel had less significant changes in the rheological parameters during the FT cycles than starch/guar gum or xanthan gum gel systems. SEM images showed that PLC stabilized the gel matrix surrounding pores, which would contribute to both a lower syneresis production and a higher stability in the rheological behavior at FT. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modification of starch metabolism in transgenic Arabidopsis thaliana increases plant biomass and triples oilseed production.

PubMed

Liu, Fushan; Zhao, Qianru; Mano, Noel; Ahmed, Zaheer; Nitschke, Felix; Cai, Yinqqi; Chapman, Kent D; Steup, Martin; Tetlow, Ian J; Emes, Michael J

2016-03-01

We have identified a novel means to achieve substantially increased vegetative biomass and oilseed production in the model plant Arabidopsis thaliana. Endogenous isoforms of starch branching enzyme (SBE) were substituted by either one of the endosperm-expressed maize (Zea mays L.) branching isozymes, ZmSBEI or ZmSBEIIb. Transformants were compared with the starch-free background and with the wild-type plants. Each of the maize-derived SBEs restored starch biosynthesis but both morphology and structure of starch particles were altered. Altered starch metabolism in the transformants is associated with enhanced biomass formation and more-than-trebled oilseed production while maintaining seed oil quality. Enhanced oilseed production is primarily due to an increased number of siliques per plant whereas oil content and seed number per silique are essentially unchanged or even modestly decreased. Introduction of cereal starch branching isozymes into oilseed plants represents a potentially useful strategy to increase biomass and oilseed production in related crops and manipulate the structure and properties of leaf starch. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Rheological Behavior, Granule Size Distribution and Differential Scanning Calorimetry of Cross-Linked Banana (Musa paradisiaca) Starch.

NASA Astrophysics Data System (ADS)

Núñez-Santiago, María C.; Maristany-Cáceres, Amira J.; Suárez, Francisco J. García; Bello-Pérez, Arturo

2008-07-01

Rheological behavior at 60 °C, granule size distribution and Differential Scanning Calorimetry (DSC) tests were employed to study the effect of diverse reaction conditions: adipic acid concentration, pH and temperature during cross-linking of banana (Musa paradisiaca) starch. These properties were determined in native banana starch pastes for the purpose of comparison. Rheological behavior from pastes of cross-linked starch at 60 °C did not show hysteresis, probably due the cross-linkage of starch that avoided disruption of granules, elsewhere, native starch showed hysteresis in a thixotropic loop. All pastes exhibited non-Newtonian shear thinning behavior. In all cases, size distribution showed a decrease in the median diameter in cross-linked starches. This condition produces a decrease in swelling capacity of cross-linked starch. The median diameter decreased with an increase of acid adipic concentration; however, an increase of pH and Temperature produced an increase in this variable. Finally, an increase in gelatinization temperature and entalphy (ΔH) were observed as an effect of cross-linkage. An increase in acid adipic concentration produced an increase in Tonset and a decrease in ΔH. pH and temperature. The cross-linked of banana starch produced granules more resistant during the pasting procedure.

The regulatory effects of resistant starch on glycaemic response in obese dogs.

PubMed

Kimura, Tohru

2013-12-01

The purpose of this study was to examine the inhibitory effects of resistant starch on postprandial glycaemic response in obese dogs. The changes in blood glucose concentrations and glycaemic index (GI) were chronologically determined after the administration of resistant and normal starches by nasal feeding. Resistant starch contained indigestible dextrin (IDD) and β-cyclic dextrin (β-CD). Soluble starch (SS) served as a control starch. Glucose concentrations reached their maximum 15 min after the administration of SS solutions, and decreased gradually during the experimental period. In contrast, after the administration of IDD solutions, increased glucose concentrations rapidly decreased to the initial values. After the administration of β-CD solutions, glucose concentrations remained unchanged during this study. GI levels remained constant in the following order: β-CD < IDD < SS. GI levels of dogs receiving IDD and β-CD solutions were significantly lower as compared with those animals receiving SS solutions. In this study, nasal tube feeding was an effective method for evaluating glycaemic responses to various starches accurately. The present data revealed that resistant starches were useful materials in controlling nutritionally glucose concentrations in obese dogs. These results raise the possibility that resistant starches are valuable for dietetic treatment of diabetes and obesity in dogs.

Plastidial Folate Prevents Starch Biosynthesis Triggered by Sugar Influx into Non-Photosynthetic Plastids of Arabidopsis

PubMed Central

Hayashi, Makoto; Tanaka, Mina; Yamamoto, Saki; Nakagawa, Taro; Kanai, Masatake; Anegawa, Aya; Ohnishi, Miwa; Mimura, Tetsuro; Nishimura, Mikio

2017-01-01

Abstract Regulation of sucrose–starch interconversion in plants is important to maintain energy supplies necessary for viability and growth. Arabidopsis mutants were screened for aberrant responses to sucrose to identify candidates with a defect in the regulation of starch biosynthesis. One such mutant, fpgs1-4, accumulated substantial amounts of starch in non-photosynthetic cells. Dark-grown mutant seedlings exhibited shortened hypocotyls and accumulated starch in etioplasts when supplied with exogenous sucrose/glucose. Similar starch accumulation from exogenous sucrose was observed in mutant chloroplasts, when photosynthesis was prevented by organ culture in darkness. Molecular genetic analyses revealed that the mutant was defective in plastidial folylpolyglutamate synthetase, one of the enzymes engaged in folate biosynthesis. Active folate derivatives are important biomolecules that function as cofactors for a variety of enzymes. Exogenously supplied 5-formyl-tetrahydrofolate abrogated the mutant phenotypes, indicating that the fpgs1-4 mutant produced insufficient folate derivative levels. In addition, the antifolate agents methotrexate and 5-fluorouracil induced starch accumulation from exogenously supplied sucrose in dark-grown seedlings of wild-type Arabidopsis. These results indicate that plastidial folate suppresses starch biosynthesis triggered by sugar influx into non-photosynthetic cells, demonstrating a hitherto unsuspected link between plastidial folate and starch metabolism. PMID:28586467

Effect of heat moisture treatment (HMT) on product quality of sorghum starch

NASA Astrophysics Data System (ADS)

Haryani, Kristinah; Hadiyanto, Handayani, Noera; Nugraheni, Dwi; Suryanto

2015-12-01

Sorghum is a cereal plant that rich of nutrition contents. The high content of carbohydrate in sorghum make this plant can be processed into one of the processed food i.e vermicelli. To give better quality, it is necessary to use flour substitution from sorghum starch. The aim of this study was to evaluate the treatment of natural sorghum starch substitution, the addition of CMC, and a comparison of the natural starch with starch sorghum forage sorghum against solid losses value, rehydration weight and texture profiles. The variable used in this study: amount of natural sorghum starch subtituion (10%, 20%, 30%, 40%, 50%), the addition of CMC (0.1%; 0.2%; 0.3%; 0.4%; 0.5%) and substituting sorghum starch Natural: HMT sorghum starch (1: 1; 1: 2; 1: 3; 1: 4; 1: 5) and the quality parameters were evaluated. The result indicated that to substitute sorghum starch naturally at a rate of 50% had the best results with a value of solid losses 5.1% (white sorghum) 5.83% (red sorghum) and weighing rehydration 301.82% (white sorghums) 293.16% (red sorghum), the addition of CMC with 0.5% concentration of 3.96% solid losses value (red sorghum) 4:21% (white sorghums) and weight rehydration 252.71% (white sorghums) 244.45% (red sorghums).

Morphological, structural, thermal, compositional, vibrational, and pasting characterization of white, yellow, and purple Arracacha Lego-like starches and flours (Arracacia xanthorrhiza).

PubMed

Londoño-Restrepo, Sandra M; Rincón-Londoño, Natalia; Contreras-Padilla, Margarita; Millan-Malo, Beatriz M; Rodriguez-Garcia, Mario E

2018-07-01

This work is focused on the chemical, structural, morphological, thermal, IR vibrational, and pasting characterization of isolated white, yellow, and purple Arracacha starches from Colombia. Inductive couple plasma showed that these starches are rich in potassium. Scanning Electron Microscopy (SEM) images show that the starch granules are formed by ovoid fully filled Lego-like starch microparticles, the circular cross-section has a diameter between 9 and 15μm and mayor axis between 20 and 30μm. Each one of these ovoids is formed by irregular wedge-shaped 6 to 10 isolated starch granules with an average size between 4 and 12μm. The amylose content ranged between 31 and 36%. Arracacha starches exhibited high viscosity values (between 20.000 and 28.000cP), which could be influenced by the high content of potassium ions, due to the C-H~K Van Der Waals interaction that was identified by using IR spectroscopy. According to the X-ray diffraction analysis, the starch patterns exhibited broad diffracted peaks which could be associated with the existence of nano-crystals and lamellae; the Differential Scanning calorimetry (DSC) result showed starches with a low gelatinization temperature of about 60°C. Copyright © 2018 Elsevier B.V. All rights reserved.

Combining mutations at genes encoding key enzymes involved in starch synthesis affects the amylose content, carbohydrate allocation and hardness in the wheat grain.

PubMed

Botticella, Ermelinda; Sestili, Francesco; Sparla, Francesca; Moscatello, Stefano; Marri, Lucia; Cuesta-Seijo, Jose A; Falini, Giuseppe; Battistelli, Alberto; Trost, Paolo; Lafiandra, Domenico

2018-03-02

Modifications to the composition of starch, the major component of wheat flour, can have a profound effect on the nutritional and technological characteristics of the flour's end products. The starch synthesized in the grain of conventional wheats (Triticum aestivum) is a 3:1 mixture of the two polysaccharides amylopectin and amylose. Altering the activity of certain key starch synthesis enzymes (GBSSI, SSIIa and SBEIIa) has succeeded in generating starches containing a different polysaccharide ratio. Here, mutagenesis, followed by a conventional marker-assisted breeding exercise, has been used to generate three mutant lines that produce starch with an amylose contents of 0%, 46% and 79%. The direct and pleiotropic effects of the multiple mutation lines were identified at both the biochemical and molecular levels. Both the structure and composition of the starch were materially altered, changes which affected the functionality of the starch. An analysis of sugar and nonstarch polysaccharide content in the endosperm suggested an impact of the mutations on the carbon allocation process, suggesting the existence of cross-talk between the starch and carbohydrate synthesis pathways. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Effect of starch type on the physico-chemical properties of edible films.

PubMed

Basiak, Ewelina; Lenart, Andrzej; Debeaufort, Frédéric

2017-05-01

Food preservation is mostly related to packaging in oil-based plastics, inducing environmental problems, but this drawback could be limited by using edible/biodegradable films and coatings. Physical and chemical properties were assessed and reflect the role of the starch type (wheat, corn or potato) and thus that of the amylose/amylopectin ratio, which influences thickness, colour, moisture, wettability, thermal, surface and mechanical properties. Higher amylose content in films induces higher moisture sensitivity, and thus affects the mechanical and barrier properties. Films made from potato starch constitute a greater barrier for oxygen and water vapour though they have weaker mechanical properties than wheat and corn starch films. Starch species with higher amylose content have lower wettability properties, and better mechanical resistance, which strongly depends on the water content due to the hydrophilic nature of starch films, so they could be used for products with higher water activity, such as cheese, fruits and vegetables. It especially concerns wheat starch systems, and the contact angle indicates less hydrophilic surfaces (above 90°) than those of corn and potato starch films (below 90°). The starch origin influences optical properties and thickness: with more amylose, films are opalescent and thicker; with less, they are transparent and thinner. Copyright © 2017 Elsevier B.V. All rights reserved.

Antimicrobial nanostructured starch based films for packaging.

PubMed

Abreu, Ana S; Oliveira, M; de Sá, Arsénio; Rodrigues, Rui M; Cerqueira, Miguel A; Vicente, António A; Machado, A V

2015-09-20

Montmorillonite modified with a quaternary ammonium salt C30B/starch nanocomposite (C30B/ST-NC), silver nanoparticles/starch nanocomposite (Ag-NPs/ST-NC) and both silver nanoparticles/C30B/starch nanocomposites (Ag-NPs/C30B/ST-NC) films were produced. The nanoclay (C30B) was dispersed in a starch solution using an ultrasonic probe. Different concentrations of Ag-NPs (0.3, 0.5, 0.8 and 1.0mM) were synthesized directly in starch and in clay/starch solutions via chemical reduction method. Dispersion of C30B silicate layers and Ag-NPs in ST films characterized by X-ray and scanning electron microscopy showed that the presence of Ag-NPs enhanced clay dispersion. Color and opacity measurements, barrier properties (water vapor and oxygen permeabilities), dynamic mechanical analysis and contact angle were evaluated and related with the incorporation of C30B and Ag-NPs. Films presented antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans without significant differences between Ag-NPs concentrations. The migration of components from the nanostructured starch films, assessed by food contact tests, was minor and under the legal limits. These results indicated that the starch films incorporated with C30B and Ag-NPs have potential to be used as packaging nanostructured material. Copyright © 2015 Elsevier Ltd. All rights reserved.

Physicochemical properties of quinoa flour as affected by starch interactions.

PubMed

Li, Guantian; Zhu, Fan

2017-04-15

There has been growing interest in whole grain quinoa flour for new product development due to the unique nutritional benefits. The quality of quinoa flour is much determined by the properties of its major component starch as well as non-starch components. In this study, composition and physicochemical properties of whole grain flour from 7 quinoa samples have been analyzed. Flour properties have been correlated to the flour composition and the properties of isolated quinoa starches through chemometrics. Great variations in chemical composition, swelling power, water soluble index, enzyme susceptibility, pasting, gel texture, and thermal properties of the flour have been observed. Correlation analysis showed that thermal properties and enzyme susceptibility of quinoa flour are highly influenced by the starch. Interactions of starch with non-starch components, including lipids, protein, dietary fibre, phenolics, and minerals, greatly impacted the flour properties. For example, peak gelatinization temperature of the flour is positively correlated to that of the starch (r=0.948, p<0.01) and negatively correlated to the lipid content (r=-0.951, p<0.01). Understanding the roles of starch and other components in physicochemical properties of quinoa flour provides a basis for better utilization of this specialty crop. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of genotype and ensiling of corn grain on in situ degradation of starch in the rumen.

PubMed

Philippeau, C; Michalet-Doreau, B

1998-08-01

This trial was conducted to determine the influence of genotype and ensiling of corn grain on the rate and extent of ruminal starch degradation. Two cultivars of corn that differed in texture of the endosperm, dent (Zea mays ssp. indentata) or flint (Zea mays ssp. indentura) were harvested at 30% whole-plant dry matter (DM). After separation from stover and cob, the kernels were coarsely chopped and ensiled or not ensiled. Grains were oven-dried at 40 degrees C and either ground through a 3-mm sieve or left unground. Ruminal DM and starch degradabilities were determined using the in situ technique. The proportion of starch lost through the pores of the bag without degradation was also determined. Mean ruminal DM and starch degradabilities were higher for ground grains than for chopped grains, which could be related to the proportion of DM and starch lost through the pores of the bag. For unensiled, chopped grain, ruminal starch degradability was higher for dent corn than for flint corn (72.3% vs. 61.6%). The ensiling process increased ruminal starch degradability, averaging 5.8 percentage units. The difference in ruminal starch degradability between dent corn and flint corn remained constant whether the corn was unensiled or ensiled (10.7 vs. 11.6 percentage units).

Rethinking the starch digestion hypothesis for AMY1 copy number variation in humans.

PubMed

Fernández, Catalina I; Wiley, Andrea S

2017-08-01

Alpha-amylase exists across taxonomic kingdoms with a deep evolutionary history of gene duplications that resulted in several α-amylase paralogs. Copy number variation (CNV) in the salivary α-amylase gene (AMY1) exists in many taxa, but among primates, humans appear to have higher average AMY1 copies than nonhuman primates. Additionally, AMY1 CNV in humans has been associated with starch content of diets, and one known function of α-amylase is its involvement in starch digestion. Thus high AMY1 CNV is considered to result from selection favoring more efficient starch digestion in the Homo lineage. Here, we present several lines of evidence that challenge the hypothesis that increased AMY1 CNV is an adaptation to starch consumption. We observe that α- amylase plays a very limited role in starch digestion, with additional steps required for starch digestion and glucose metabolism. Specifically, we note that α-amylase hydrolysis only produces a minute amount of free glucose with further enzymatic digestion and glucose absorption being rate-limiting steps for glucose availability. Indeed α-amylase is nonessential for starch digestion since sucrase-isomaltase and maltase-glucoamylase can hydrolyze whole starch granules while releasing glucose. While higher AMY1 CN and CNV among human populations may result from natural selection, existing evidence does not support starch digestion as the major selective force. We report that in humans α-amylase is expressed in several other tissues where it may have potential roles of evolutionary significance. © 2017 Wiley Periodicals, Inc.

Starch accumulation in hulless barley during grain filling.

PubMed

Zheng, Xu-Guang; Qi, Jun-Cang; Hui, Hong-Shan; Lin, Li-Hao; Wang, Feng

2017-12-01

Starch consists of two types of molecules: amylose and amylopectin. The objective of this study was increase understanding about mechanisms related to starch accumulation in hulless barley (Hordeum vulgare L.) grain by measuring temporal changes in (i) grain amylose and amylopectin content, (ii) starch synthase activity, and (iii) the relative expressions of key starch-related genes. The amylopectin/amylose ratio gradually declined in both Beiqing 6 and Kunlun 12. In both cultivars, the activities of adenosine diphosphate glucose pyrophosphorylase, soluble starch synthase (SSS), granule bound starch synthase (GBSS), and starch branching enzyme (SBE) increased steadily during grain filling, reaching their maximums 20-25 days after anthesis. The activities of SSS and SBE were greater in Ganken 5 than in either Beiqing 6 or Kunlun 12. The expression of GBSS I was greater in Beiqing 6 and Kunlun 12 than in Ganken 5. In contrast, the expression of SSS I, SSS II and SBE I was greater in Ganken 5 than in Beiqing 6 and Kunlun 12. The peak in GBSS I expression was later than that of SSS I, SSS II, SBE IIa and SBE IIb. The GBSS I transcript in Kunlun 12 was expressed on average 90 times more than the GBSS II transcript. The results suggest that SBE and SSS may control starch synthesis at the transcriptional level, whereas GBSS I may control starch synthesis at the post transcriptional level. GBSS I is mainly responsible for amylose synthesis whereas SSS I and SBE II are mainly responsible for amylopectin synthesis in amyloplasts.

Effect of starch and amylase on the expression of amylase-binding protein A in Streptococcus gordonii

PubMed Central

Nikitkova, A.E.; Haase, E.M.; Scannapieco, F.A.

2012-01-01

SUMMARY Streptococcus gordonii is a common oral commensal bacterial species in tooth biofilm (dental plaque) and specifically binds to salivary amylase through the surface exposed amylase-binding protein A (AbpA). When S. gordonii cells are pretreated with amylase, amylase bound to AbpA facilitates growth with starch as a primary nutrition source. The goal of this study was to explore possible regulatory effects of starch, starch metabolites and amylase on the expression of S. gordonii AbpA. An amylase ligand-binding assay was used to assess the expression of AbpA in culture supernatants and on bacterial cells from S. gordonii grown in defined medium supplemented with 1% starch, 0.5 mg ml−1 amylase, with starch and amylase together, or with various linear malto-oligosaccharides. Transcription of abpA was determined by reverse transcription quantitative polymerase chain reaction. AbpA was not detectable in culture supernatants containing either starch alone or amylase alone. In contrast, the amount of AbpA was notably increased when starch and amylase were both present in the medium. The expression of abpA was significantly increased (P < 0.05) following 40 min of incubation in defined medium supplemented with starch and amylase. Similar results were obtained in the presence of maltose and other short-chain malto-oligosacchrides. These results suggest that the products of starch hydrolysis produced from the action of salivary α-amylase, particularly maltose and maltotriose, regulate AbpA expression in S. gordonii. PMID:22759313

Effect of carboxymethyl cellulose (CMC) as biopolymers to the edible film sorghum starch hydrophobicity characteristics

NASA Astrophysics Data System (ADS)

Putri, Rr. Dewi Artanti; Setiawan, Aji; Anggraini, Puji D.

2017-03-01

The use of synthetic plastic should be limited because it causes the plastic waste that can not be decomposed quickly, triggering environmental problems. The solution of the plastic usage is the use of biodegradable plastic as packaging which is environmentally friendly. Synthesis of edible film can be done with a variety of components. The component mixture of starch and cellulose derivative products are one of the methods for making edible film. Sorghum is a species of cereal crops containing starch amounted to 80.42%, where the use of sorghum in Indonesia merely fodder. Therefore, sorghum is a potential material to be used as a source of starch synthesis edible film. This research aims to study the characteristics of edible starch films Sorghum and assess the effect of CMC (Carboxymethyl Cellulose) as additional materials on the characteristics of biopolymers edible film produced sorghum starch. This study is started with the production of sorghum starch, then the film synthesizing with addition of CMC (5, 10, 15, 20, and 25% w/w starch), and finally the hydrophobicity characteristics test (water uptake test and water solubility test). The addition of CMC will decrease the percentage of water absorption to the film with lowest level of 65.8% in the degree of CMC in 25% (w/w starch). The addition of CMC also influences the water solubility of film, where in the degree of 25% CMC (w/w starch) the solubility of water was the lowest, which was 28.2% TSM.

Effects of structural imperfection on gelatinization characteristics of amylopectin starches with A- and B-type crystallinity.

PubMed

Genkina, Natalia K; Wikman, Jeanette; Bertoft, Eric; Yuryev, Vladimir P

2007-07-01

The aim of the present work was to investigate the effect of physical structures on the properties of starch granules. Starches with a high amylopectin content possessing A- and B-type crystallinity were chosen for the study. The gelatinization temperature decreased in the following order: maize (A) > potato (B) > wheat (A) > barley (A), which did not reflect a correlation with the type of crystallinity. Low values of gelatinization temperature were accompanied with high free surface energy of the crystallites. It is proposed that these data are caused by different types of imperfections in starch crystals. Annealing resulted in an enhancement of the gelatinization temperature and a decrease of the free surface energy of the crystallites for all starches reflecting a partial improvement of crystalline perfection. A limited acid hydrolysis (lintnerization) of the starches decreased the gelatinization temperature because of a partial disruption of the crystalline lamellae and an increase of the amount of defects on the edges of the crystallites. Annealing of the lintnerized starches improved the structure of maize and potato starch, giving them similar structural and physicochemical parameters, which was opposite the behavior of the annealed sample from wheat. The possible nature of removable and nonremovable defects inside the crystalline region of the starch granules is discussed. It is concluded that, besides the allomorphic A- and B-types of crystal packing, physical defects in the crystals possess a major impact on starch gelatinization.

Investigation on the pitting of potato starch granules during high frequency ultrasound treatment.

PubMed

Bai, Wenzhe; Hébraud, Pascal; Ashokkumar, Muthupandian; Hemar, Yacine

2017-03-01

In this paper, the pitting of potato starch granules in aqueous suspensions (1%) by high-frequency high-power ultrasound (850kHz at a power of 0.2W, 2W or 3.7W; and also 500kHz and 1MHz at a power of 2W) is reported. The number of pits per starch granules was found to be independent of the amylose content of starches, and the surface properties of starch granules as modified through SDS and ethanol washing. At 850kHz, the maximum number of pits per starch granule, for both normal and waxy starches, did not exceed 11. However, a close inspection of fractionated starch granules based on their sizes showed that there is an optimum granule size for which a maximum pit number is obtained. For example, starch granules with diameter size range of ∼15 to ∼30μm had a maximum pit number (between 10 and 20 pits per granule) when sonicated (2W, 850kHz and 30min); while sonication of small (<10μm) and very large (>45μm) granules resulted in a smaller number of pits per granule (∼5). Further, the maximum number of pits per granules is also found to be proportional to the ultrasound frequency, with values of approximately 7, 10 and 11 at 0.50, 0.85, and 1MHz, respectively. FTIR measurements did not show any breakup of starch molecules. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of Function of the GlgA2 Glycogen/Starch Synthase in Cyanobacterium sp. Clg1 Highlights Convergent Evolution of Glycogen Metabolism into Starch Granule Aggregation1

PubMed Central

Kadouche, Derifa; Arias, Maria Cecilia

2016-01-01

At variance with the starch-accumulating plants and most of the glycogen-accumulating cyanobacteria, Cyanobacterium sp. CLg1 synthesizes both glycogen and starch. We now report the selection of a starchless mutant of this cyanobacterium that retains wild-type amounts of glycogen. Unlike other mutants of this type found in plants and cyanobacteria, this mutant proved to be selectively defective for one of the two types of glycogen/starch synthase: GlgA2. This enzyme is phylogenetically related to the previously reported SSIII/SSIV starch synthase that is thought to be involved in starch granule seeding in plants. This suggests that, in addition to the selective polysaccharide debranching demonstrated to be responsible for starch rather than glycogen synthesis, the nature and properties of the elongation enzyme define a novel determinant of starch versus glycogen accumulation. We show that the phylogenies of GlgA2 and of 16S ribosomal RNA display significant congruence. This suggests that this enzyme evolved together with cyanobacteria when they diversified over 2 billion years ago. However, cyanobacteria can be ruled out as direct progenitors of the SSIII/SSIV ancestral gene found in Archaeplastida. Hence, both cyanobacteria and plants recruited similar enzymes independently to perform analogous tasks, further emphasizing the importance of convergent evolution in the appearance of starch from a preexisting glycogen metabolism network. PMID:27208262

Characterization of Function of the GlgA2 Glycogen/Starch Synthase in Cyanobacterium sp. Clg1 Highlights Convergent Evolution of Glycogen Metabolism into Starch Granule Aggregation.

PubMed

Kadouche, Derifa; Ducatez, Mathieu; Cenci, Ugo; Tirtiaux, Catherine; Suzuki, Eiji; Nakamura, Yasunori; Putaux, Jean-Luc; Terrasson, Amandine Durand; Diaz-Troya, Sandra; Florencio, Francisco Javier; Arias, Maria Cecilia; Striebeck, Alexander; Palcic, Monica; Ball, Steven G; Colleoni, Christophe

2016-07-01

At variance with the starch-accumulating plants and most of the glycogen-accumulating cyanobacteria, Cyanobacterium sp. CLg1 synthesizes both glycogen and starch. We now report the selection of a starchless mutant of this cyanobacterium that retains wild-type amounts of glycogen. Unlike other mutants of this type found in plants and cyanobacteria, this mutant proved to be selectively defective for one of the two types of glycogen/starch synthase: GlgA2. This enzyme is phylogenetically related to the previously reported SSIII/SSIV starch synthase that is thought to be involved in starch granule seeding in plants. This suggests that, in addition to the selective polysaccharide debranching demonstrated to be responsible for starch rather than glycogen synthesis, the nature and properties of the elongation enzyme define a novel determinant of starch versus glycogen accumulation. We show that the phylogenies of GlgA2 and of 16S ribosomal RNA display significant congruence. This suggests that this enzyme evolved together with cyanobacteria when they diversified over 2 billion years ago. However, cyanobacteria can be ruled out as direct progenitors of the SSIII/SSIV ancestral gene found in Archaeplastida. Hence, both cyanobacteria and plants recruited similar enzymes independently to perform analogous tasks, further emphasizing the importance of convergent evolution in the appearance of starch from a preexisting glycogen metabolism network. © 2016 American Society of Plant Biologists. All Rights Reserved.

Carbohydrate-binding module 74 is a novel starch-binding domain associated with large and multidomain α-amylase enzymes.

PubMed

Valk, Vincent; Lammerts van Bueren, Alicia; van der Kaaij, Rachel M; Dijkhuizen, Lubbert

2016-06-01

Microbacterium aurum B8.A is a bacterium that originates from a potato starch-processing plant and employs a GH13 α-amylase (MaAmyA) enzyme that forms pores in potato starch granules. MaAmyA is a large and multi-modular protein that contains a novel domain at its C terminus (Domain 2). Deletion of Domain 2 from MaAmyA did not affect its ability to degrade starch granules but resulted in a strong reduction in granular pore size. Here, we separately expressed and purified this Domain 2 in Escherichia coli and determined its likely function in starch pore formation. Domain 2 independently binds amylose, amylopectin, and granular starch but does not have any detectable catalytic (hydrolytic or oxidizing) activity on α-glucan substrates. Therefore, we propose that this novel starch-binding domain is a new carbohydrate-binding module (CBM), the first representative of family CBM74 that assists MaAmyA in efficient pore formation in starch granules. Protein sequence-based BLAST searches revealed that CBM74 occurs widespread, but in bacteria only, and is often associated with large and multi-domain α-amylases containing family CBM25 or CBM26 domains. CBM74 may specifically function in binding to granular starches to enhance the capability of α-amylase enzymes to degrade resistant starches (RSs). Interestingly, the majority of family CBM74 representatives are found in α-amylases originating from human gut-associated Bifidobacteria, where they may assist in resistant starch degradation. The CBM74 domain thus may have a strong impact on the efficiency of RS digestion in the mammalian gastrointestinal tract. © 2016 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

Composition and physical properties of starch in microgravity-grown plants.

PubMed

Kuznetsov, O A; Brown, C S; Levine, H G; Piastuch, W C; Sanwo-Lewandowski, M M; Hasenstein, K H

2001-01-01

The effect of spaceflight on starch development in soybean (Glycine max L., BRIC-03) and potato (Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio delta X/delta rho (delta X --difference of magnetic susceptibilities, delta rho--difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm3), the observed difference in delta X/delta rho was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with alpha-amylase for 24 hours, 77 +/- 6% of the starch from the flight cotyledons was degraded compared to 58 +/- 12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and delta X/delta rho suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, delta X/delta rho and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity. c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Feedback Inhibition of Starch Degradation in Arabidopsis Leaves Mediated by Trehalose 6-Phosphate1[W][OPEN

PubMed Central

Martins, Marina Camara Mattos; Hejazi, Mahdi; Fettke, Joerg; Steup, Martin; Feil, Regina; Krause, Ursula; Arrivault, Stéphanie; Vosloh, Daniel; Figueroa, Carlos María; Ivakov, Alexander; Yadav, Umesh Prasad; Piques, Maria; Metzner, Daniela; Stitt, Mark; Lunn, John Edward

2013-01-01

Many plants accumulate substantial starch reserves in their leaves during the day and remobilize them at night to provide carbon and energy for maintenance and growth. In this paper, we explore the role of a sugar-signaling metabolite, trehalose-6-phosphate (Tre6P), in regulating the accumulation and turnover of transitory starch in Arabidopsis (Arabidopsis thaliana) leaves. Ethanol-induced overexpression of trehalose-phosphate synthase during the day increased Tre6P levels up to 11-fold. There was a transient increase in the rate of starch accumulation in the middle of the day, but this was not linked to reductive activation of ADP-glucose pyrophosphorylase. A 2- to 3-fold increase in Tre6P during the night led to significant inhibition of starch degradation. Maltose and maltotriose did not accumulate, suggesting that Tre6P affects an early step in the pathway of starch degradation in the chloroplasts. Starch granules isolated from induced plants had a higher orthophosphate content than granules from noninduced control plants, consistent either with disruption of the phosphorylation-dephosphorylation cycle that is essential for efficient starch breakdown or with inhibition of starch hydrolysis by β-amylase. Nonaqueous fractionation of leaves showed that Tre6P is predominantly located in the cytosol, with estimated in vivo Tre6P concentrations of 4 to 7 µm in the cytosol, 0.2 to 0.5 µm in the chloroplasts, and 0.05 µm in the vacuole. It is proposed that Tre6P is a component in a signaling pathway that mediates the feedback regulation of starch breakdown by sucrose, potentially linking starch turnover to demand for sucrose by growing sink organs at night. PMID:24043444

Variations in zonal fruit starch concentrations of apples – a developmental phenomenon or an indication of ripening?

PubMed Central

Doerflinger, Franziska C; Miller, William B; Nock, Jacqueline F; Watkins, Christopher B

2015-01-01

Patterns of starch hydrolysis in stem, equatorial, and calyx zones of ‘Honeycrisp’ and ‘Empire’ apples (Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.) during maturation and ripening, and in ‘Gala’ apples in response to propylene or 1-methylcyclopropene (1-MCP) treatments after harvest, were studied. Differences in zonal starch concentrations were found for ‘Empire’ and ‘Gala’ fruits, but not for ‘Honeycrisp’. During maturation and ripening of ‘Empire’, the concentration of starch was highest in the calyx end and lowest in the stem region. Differences in rates of starch hydrolysis among zones were not detected. ‘Honeycrisp’ and ‘Empire’ had the highest concentration of sorbitol in the calyx region, whereas it was highest in the stem-end region in ‘Gala’. The distribution differences of glucose, fructose, and sucrose were similar in all three cultivars; higher fructose and glucose concentrations in the stem region, and higher sucrose concentrations in the calyx end of the fruit. Postharvest treatment of ‘Gala’ with propylene did not affect the internal ethylene concentration of the fruit but 1-MCP markedly inhibited it. Starch concentrations were highest in the calyx end but gradients of starch among zones were not changed by postharvest treatment. The rate of hydrolysis was slowed by 1-MCP treatment, but was unaffected by propylene. Postharvest treatments influenced sorbitol, glucose, and fructose concentrations. Patterns of starch concentration among the zones did not confirm differences in ripening, but reflected its uneven distribution throughout the fruit during development. Therefore, measured differences in zonal starch are most likely related to starch accumulation during fruit development, rather than differences in rates of starch degradation during ripening. PMID:26504584

Composition and physical properties of starch in microgravity-grown plants

NASA Technical Reports Server (NTRS)

Kuznetsov, O. A.; Brown, C. S.; Levine, H. G.; Piastuch, W. C.; Sanwo-Lewandowski, M. M.; Hasenstein, K. H.; Sager, J. C. (Principal Investigator)

2001-01-01

The effect of spaceflight on starch development in soybean (Glycine max L., BRIC-03) and potato (Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio delta X/delta rho (delta X --difference of magnetic susceptibilities, delta rho--difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm3), the observed difference in delta X/delta rho was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with alpha-amylase for 24 hours, 77 +/- 6% of the starch from the flight cotyledons was degraded compared to 58 +/- 12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and delta X/delta rho suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, delta X/delta rho and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity. c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Feedback inhibition of starch degradation in Arabidopsis leaves mediated by trehalose 6-phosphate.

PubMed

Martins, Marina Camara Mattos; Hejazi, Mahdi; Fettke, Joerg; Steup, Martin; Feil, Regina; Krause, Ursula; Arrivault, Stéphanie; Vosloh, Daniel; Figueroa, Carlos María; Ivakov, Alexander; Yadav, Umesh Prasad; Piques, Maria; Metzner, Daniela; Stitt, Mark; Lunn, John Edward

2013-11-01

Many plants accumulate substantial starch reserves in their leaves during the day and remobilize them at night to provide carbon and energy for maintenance and growth. In this paper, we explore the role of a sugar-signaling metabolite, trehalose-6-phosphate (Tre6P), in regulating the accumulation and turnover of transitory starch in Arabidopsis (Arabidopsis thaliana) leaves. Ethanol-induced overexpression of trehalose-phosphate synthase during the day increased Tre6P levels up to 11-fold. There was a transient increase in the rate of starch accumulation in the middle of the day, but this was not linked to reductive activation of ADP-glucose pyrophosphorylase. A 2- to 3-fold increase in Tre6P during the night led to significant inhibition of starch degradation. Maltose and maltotriose did not accumulate, suggesting that Tre6P affects an early step in the pathway of starch degradation in the chloroplasts. Starch granules isolated from induced plants had a higher orthophosphate content than granules from noninduced control plants, consistent either with disruption of the phosphorylation-dephosphorylation cycle that is essential for efficient starch breakdown or with inhibition of starch hydrolysis by β-amylase. Nonaqueous fractionation of leaves showed that Tre6P is predominantly located in the cytosol, with estimated in vivo Tre6P concentrations of 4 to 7 µm in the cytosol, 0.2 to 0.5 µm in the chloroplasts, and 0.05 µm in the vacuole. It is proposed that Tre6P is a component in a signaling pathway that mediates the feedback regulation of starch breakdown by sucrose, potentially linking starch turnover to demand for sucrose by growing sink organs at night.

A novel process for direct production of acetone-butanol-ethanol from native starches using granular starch hydrolyzing enzyme by Clostridium saccharoperbutylacetonicum N1-4.

PubMed

Thang, Vu Hong; Kobayashi, Genta

2014-02-01

In this work, a new approach for acetone-butanol-ethanol (ABE) production has been proposed. Direct fermentation of native starches (uncooked process) was investigated by using granular starch hydrolyzing enzyme (GSHE) and Clostridium saccharoperbutylacetonicum N1-4. Even the process was carried out under suboptimal condition for activity of GSHE, the production of ABE was similar with that observed in conventional process or cooked process in terms of final solvent concentration (21.3 ± 0.4 to 22.4 ± 0.4 g/L), butanol concentration (17.5 ± 0.4 to 17.8 ± 0.3 g/L) and butanol yield (0.33 to 0.37 g/g). The production of solvents was significantly dependent on the source of starches. Among investigated starches, corn starch was more susceptible to GSHE while cassava starch was the most resistant to this enzyme. Fermentation using native corn starch resulted in the solvent productivity of 0.47 g/L h, which was about 15 % higher than that achieved in cooked process. On the contrary, uncooked process using cassava and wheat starch resulted in the solvent productivity of 0.30 and 0.37 g/L h, which were respectively about 30 % lower than those obtained in cooked process. No contamination was observed during all trials even fermentation media were prepared without sterilization. During the fermentation using native starches, no formation of foam is observed. This uncooked process does not require cooking starchy material; therefore, the thermal energy consumption for solvent production would remarkably be reduced in comparison with cooked process.

Verification of protein sparing by feeding carbohydrate to common carp Cyprinus carpio

NASA Astrophysics Data System (ADS)

Cheng, Zhenyan; Li, Jinghui; Zhang, Baolong; Fang, Zhenzhen; Sun, Jinhui; Bai, Dongqing; Sun, Jinsheng; Qiao, Xiuting

2017-03-01

A 9-week feeding trial in floating freshwater cages (1.0 m×1.0 m×2.0 m) was conducted to study the effects of different dietary levels of protein and starch on growth, body composition, and gene expression of enzymes in common carp, Cyprinus carpio (mean body weight, 36.12±1.18 g) to evaluate the protein-sparing effect of dietary carbohydrate. Four diets were formulated with corn starch as the carbohydrate source to obtain corn starch levels of 6.5%, 13%, 19.5%, or 26% and protein levels of 30.5%, 28.2%, 26.4%, and 24.2%. The results showed no differences in growth performance of fish fed the diets with different protein and corn starch levels, but body composition and glucose metabolic enzyme activity of carp were significantly affected by the different diets ( P< 0.05). Weight gain, specific growth rate, and the feed conversion ratio were not different in fish fed the different dietary treatments. Protein efficiency ratio increased significantly as corn starch level increased ( P< 0.05). Whole-body crude lipid composition increased with increasing dietary corn starch level ( P< 0.05). Glucokinase (GK), hexokinase, and pyruvate kinase (PK) activities increased significantly with increasing dietary corn starch level ( P< 0.05), whereas glucose-6-phosphate (G6Pase) activity decreased with increasing dietary corn starch level ( P< 0.05). GK gene expression was significantly higher in fish fed the high-corn starch diet than those fed the low-corn starch diet ( P< 0.05). G6pase gene expression tended to decrease with increasing starch level ( P> 0.05). In summary, the results indicate a protein-sparing effect by substituting carbohydrate in the diet of common carp.

Effect of nylon bag and protozoa on in vitro corn starch disappearance.

PubMed

van Zwieten, J T; van Vuuren, A M; Dijkstra, J

2008-03-01

An in vitro experiment was carried out to study whether the presence of protozoa in nylon bags can explain the underestimation of the in situ degradation of slowly degradable starch. Corn of a high (flint) and a low (dent) vitreousness variety was ground over a 3-mm screen, weighed in nylon bags with a pore size of 37 microm, and washed in cold water. Samples of washed cornstarch were incubated in 40-mL tubes with faunated and defaunated ruminal fluid. An additional amount of washed corn, in nylon bags, was inserted in each incubation tube. Incubations were carried out for 0, 2, 4, 6, 12, and 24 h, and starch residue in tube and nylon bag was determined. In general, starch disappearance from the nylon bag was less than from the tube, and was less with faunated than defaunated rumen fluid, but corn variety did not affect starch disappearance. When no protozoa were present, the disappearance of starch from the bags was higher after 6 and 12 h incubation compared with presence of protozoa. However, in the tubes, there was no difference in starch disappearance due to presence or absence of protozoa. Estimated lag time was higher in presence (4.6 h) then absence (3.6 h) of protozoa. It was concluded that the effect of presence or absence of protozoa on starch disappearance differs within or outside nylon bags. The reduced disappearance rate of starch inside the nylon bags in the presence of protozoa helps to explain the underestimation of starch degradation based on the in sacco procedure when compared with in vivo data upon incubation of slowly degradable starch sources.

Physical characterisation of high amylose maize starch and acylated high amylose maize starches.

PubMed

Lim, Ya-Mei; Hoobin, Pamela; Ying, DanYang; Burgar, Iko; Gooley, Paul R; Augustin, Mary Ann

2015-03-06

The particle size, water sorption properties and molecular mobility of high amylose maize starch (HAMS) and high amylose maize starch acylated with acetate (HAMSA), propionate (HAMSP) and butyrate (HAMSB) were investigated. Acylation increased the mean particle size (D(4,3)) and lowered the specific gravity (G) of the starch granules with an inverse relationship between the length of the fatty acid chain and particle size. Acylation of HAMS with fatty acids lowered the monolayer moisture content with the trend being HAMSB

An improved approach for the segmentation of starch granules in microscopic images

PubMed Central

2010-01-01

Background Starches are the main storage polysaccharides in plants and are distributed widely throughout plants including seeds, roots, tubers, leaves, stems and so on. Currently, microscopic observation is one of the most important ways to investigate and analyze the structure of starches. The position, shape, and size of the starch granules are the main measurements for quantitative analysis. In order to obtain these measurements, segmentation of starch granules from the background is very important. However, automatic segmentation of starch granules is still a challenging task because of the limitation of imaging condition and the complex scenarios of overlapping granules. Results We propose a novel method to segment starch granules in microscopic images. In the proposed method, we first separate starch granules from background using automatic thresholding and then roughly segment the image using watershed algorithm. In order to reduce the oversegmentation in watershed algorithm, we use the roundness of each segment, and analyze the gradient vector field to find the critical points so as to identify oversegments. After oversegments are found, we extract the features, such as the position and intensity of the oversegments, and use fuzzy c-means clustering to merge the oversegments to the objects with similar features. Experimental results demonstrate that the proposed method can alleviate oversegmentation of watershed segmentation algorithm successfully. Conclusions We present a new scheme for starch granules segmentation. The proposed scheme aims to alleviate the oversegmentation in watershed algorithm. We use the shape information and critical points of gradient vector flow (GVF) of starch granules to identify oversegments, and use fuzzy c-mean clustering based on prior knowledge to merge these oversegments to the objects. Experimental results on twenty microscopic starch images demonstrate the effectiveness of the proposed scheme. PMID:21047380

Application of enzyme-treated corn starches in breakfast cereal coating.

PubMed

Luckett, Curtis R; Wang, Ya-Jane

2012-08-01

Presently ready-to-eat cereals are coated with high levels of sugar coating to extend the bowl life. Because of health concerns of added sugar, there is a need to identify alternative coating materials. This study was designed to test the efficacy of debranched corn starches with varying amylose contents as a cereal coating. Hylon VII (70% amylose), common, and waxy corn starches were gelatinized and debranched, and then sprayed onto ready-to-eat breakfast cereal flakes. The surface morphology, milk absorption, texture, and digestibility of coated cereals were determined. A starch film with a thickness of 50 to 130 μm was observed with scanning electron microscopy on the surface of the cereals coated with Hylon VII. All starch-coated cereals had a lower milk absorption value than the uncoated and glucose-coated controls. Among starch coatings, common corn starch and Hylon VII resulted in lower milk absorption than did waxy corn starch. After soaking in milk for 3 min, the peak force and work to peak of the cereals coated with corn starches were higher than those of the glucose control and uncoated reference. The cereals coated with Hylon VII were found to have an increase in dietary fiber content. The results suggest that debranched amylose-containing corn starches could extend the bowl-life of ready-to-eat cereals. Currently, many cereals are coated with sugar to keep them from becoming soggy in milk. However, added sugar has been linked to obesity, hyperactivity, and dental caries. This has led to the investigation of alternative coating materials. This study employed the film-forming properties of enzyme-treated corn starch to function as a coating material in breakfast cereal flakes. In addition, the enzyme-treated high amylose corn starch also increased the dietary fiber content of the cereal flakes. © 2012 Institute of Food Technologists®

Effect of different binders on the physico-chemical, textural, histological, and sensory qualities of retort pouched buffalo meat nuggets.

PubMed

Devadason, I Prince; Anjaneyulu, A S R; Babji, Y

2010-01-01

The functional properties of 4 binders, namely corn starch, wheat semolina, wheat flour, and tapioca starches, were evaluated to improve the quality of buffalo meat nuggets processed in retort pouches at F(0) 12.13. Incorporation of corn starch in buffalo meat nuggets produced more stable emulsion than other binders used. Product yield, drip loss, and pH did not vary significantly between the products with different binders. Shear force value was significantly higher for product with corn starch (0.42 +/- 0.0 Kg/cm(3)) followed by refined wheat flour (0.36 +/- 0.010 Kg/cm(3)), tapioca starch (0.32 +/- 0.010 Kg/cm(3)), and wheat semolina (0.32 +/- 0.010 Kg/cm(3)). Type of binder used had no significant effect on frying loss, moisture, and protein content of the product. However, fat content was higher in products with corn starch when compared to products with other binders. Texture profile indicated that products made with corn starch (22.17 +/- 2.55 N) and refined wheat flour (21.50 +/- 0.75 N) contributed firmer texture to the product. Corn starch contributed greater chewiness (83.8 +/- 12.51) to the products resulting in higher sensory scores for texture and overall acceptability. Products containing corn starch showed higher sensory scores for all attributes in comparison to products with other binders. Panelists preferred products containing different binders in the order of corn starch (7.23 +/- 0.09) > refined wheat flour (6.48 +/- 0.13) > tapioca starch (6.45 +/- 0.14) > wheat semolina (6.35 +/- 0.13) based on sensory scores. Histological studies indicated that products with corn starch showed dense protein matrix, uniform fat globules, and less number of vacuoles when compared to products made with other binders. The results indicated that corn flour is the better cereal binder for developing buffalo meat nuggets when compared to all other binders based on physico-chemical and sensory attributes.

New Starch Phenotypes Produced by TILLING in Barley

PubMed Central

Sparla, Francesca; Falini, Giuseppe; Botticella, Ermelinda; Pirone, Claudia; Talamè, Valentina; Bovina, Riccardo; Salvi, Silvio; Tuberosa, Roberto; Sestili, Francesco; Trost, Paolo

2014-01-01

Barley grain starch is formed by amylose and amylopectin in a 1∶3 ratio, and is packed into granules of different dimensions. The distribution of granule dimension is bimodal, with a majority of small spherical B-granules and a smaller amount of large discoidal A-granules containing the majority of the starch. Starch granules are semi-crystalline structures with characteristic X-ray diffraction patterns. Distinct features of starch granules are controlled by different enzymes and are relevant for nutritional value or industrial applications. Here, the Targeting-Induced Local Lesions IN Genomes (TILLING) approach was applied on the barley TILLMore TILLING population to identify 29 new alleles in five genes related to starch metabolism known to be expressed in the endosperm during grain filling: BMY1 (Beta-amylase 1), GBSSI (Granule Bound Starch Synthase I), LDA1 (Limit Dextrinase 1), SSI (Starch Synthase I), SSIIa (Starch Synthase IIa). Reserve starch of nine M3 mutant lines carrying missense or nonsense mutations was analysed for granule size, crystallinity and amylose/amylopectin content. Seven mutant lines presented starches with different features in respect to the wild-type: (i) a mutant line with a missense mutation in GBSSI showed a 4-fold reduced amylose/amylopectin ratio; (ii) a missense mutations in SSI resulted in 2-fold increase in A:B granule ratio; (iii) a nonsense mutation in SSIIa was associated with shrunken seeds with a 2-fold increased amylose/amylopectin ratio and different type of crystal packing in the granule; (iv) the remaining four missense mutations suggested a role of LDA1 in granule initiation, and of SSIIa in determining the size of A-granules. We demonstrate the feasibility of the TILLING approach to identify new alleles in genes related to starch metabolism in barley. Based on their novel physicochemical properties, some of the identified new mutations may have nutritional and/or industrial applications. PMID:25271438

Genetic and isotope ratio mass spectrometric evidence for the occurrence of starch degradation and cycling in illuminated Arabidopsis leaves

PubMed Central

Baslam, Marouane; Baroja-Fernández, Edurne; Ricarte-Bermejo, Adriana; Sánchez-López, Ángela María; Aranjuelo, Iker; Bahaji, Abdellatif; Muñoz, Francisco José; Almagro, Goizeder; Pujol, Pablo; Galarza, Regina; Teixidor, Pilar; Pozueta-Romero, Javier

2017-01-01

Although there is a great wealth of data supporting the occurrence of simultaneous synthesis and breakdown of storage carbohydrate in many organisms, previous 13CO2 pulse-chase based studies indicated that starch degradation does not operate in illuminated Arabidopsis leaves. Here we show that leaves of gwd, sex4, bam4, bam1/bam3 and amy3/isa3/lda starch breakdown mutants accumulate higher levels of starch than wild type (WT) leaves when cultured under continuous light (CL) conditions. We also show that leaves of CL grown dpe1 plants impaired in the plastidic disproportionating enzyme accumulate higher levels of maltotriose than WT leaves, the overall data providing evidence for the occurrence of extensive starch degradation in illuminated leaves. Moreover, we show that leaves of CL grown mex1/pglct plants impaired in the chloroplastic maltose and glucose transporters display a severe dwarf phenotype and accumulate high levels of maltose, strongly indicating that the MEX1 and pGlcT transporters are involved in the export of starch breakdown products to the cytosol to support growth during illumination. To investigate whether starch breakdown products can be recycled back to starch during illumination through a mechanism involving ADP-glucose pyrophosphorylase (AGP) we conducted kinetic analyses of the stable isotope carbon composition (δ13C) in starch of leaves of 13CO2 pulsed-chased WT and AGP lacking aps1 plants. Notably, the rate of increase of δ13C in starch of aps1 leaves during the pulse was exceedingly higher than that of WT leaves. Furthermore, δ13C decline in starch of aps1 leaves during the chase was much faster than that of WT leaves, which provides strong evidence for the occurrence of AGP-mediated cycling of starch breakdown products in illuminated Arabidopsis leaves. PMID:28152100

New starch phenotypes produced by TILLING in barley.

PubMed

Sparla, Francesca; Falini, Giuseppe; Botticella, Ermelinda; Pirone, Claudia; Talamè, Valentina; Bovina, Riccardo; Salvi, Silvio; Tuberosa, Roberto; Sestili, Francesco; Trost, Paolo

2014-01-01

Barley grain starch is formed by amylose and amylopectin in a 1:3 ratio, and is packed into granules of different dimensions. The distribution of granule dimension is bimodal, with a majority of small spherical B-granules and a smaller amount of large discoidal A-granules containing the majority of the starch. Starch granules are semi-crystalline structures with characteristic X-ray diffraction patterns. Distinct features of starch granules are controlled by different enzymes and are relevant for nutritional value or industrial applications. Here, the Targeting-Induced Local Lesions IN Genomes (TILLING) approach was applied on the barley TILLMore TILLING population to identify 29 new alleles in five genes related to starch metabolism known to be expressed in the endosperm during grain filling: BMY1 (Beta-amylase 1), GBSSI (Granule Bound Starch Synthase I), LDA1 (Limit Dextrinase 1), SSI (Starch Synthase I), SSIIa (Starch Synthase IIa). Reserve starch of nine M3 mutant lines carrying missense or nonsense mutations was analysed for granule size, crystallinity and amylose/amylopectin content. Seven mutant lines presented starches with different features in respect to the wild-type: (i) a mutant line with a missense mutation in GBSSI showed a 4-fold reduced amylose/amylopectin ratio; (ii) a missense mutations in SSI resulted in 2-fold increase in A:B granule ratio; (iii) a nonsense mutation in SSIIa was associated with shrunken seeds with a 2-fold increased amylose/amylopectin ratio and different type of crystal packing in the granule; (iv) the remaining four missense mutations suggested a role of LDA1 in granule initiation, and of SSIIa in determining the size of A-granules. We demonstrate the feasibility of the TILLING approach to identify new alleles in genes related to starch metabolism in barley. Based on their novel physicochemical properties, some of the identified new mutations may have nutritional and/or industrial applications.

The barley amo1 locus is tightly linked to the starch synthase IIIa gene and negatively regulates expression of granule-bound starch synthetic genes

PubMed Central

Li, Zhongyi; Li, Dehong; Du, Xihua; Wang, Hong; Larroque, Oscar; Jenkins, Colin L. D.; Jobling, Stephen A.; Morell, Matthew K.

2011-01-01

In this study of barley starch synthesis, the interaction between mutations at the sex6 locus and the amo1 locus has been characterized. Four barley genotypes, the wild type, sex6, amo1, and the amo1sex6 double mutant, were generated by backcrossing the sex6 mutation present in Himalaya292 into the amo1 ‘high amylose Glacier’. The wild type, amo1, and sex6 genotypes gave starch phenotypes consistent with previous studies. However, the amo1sex6 double mutant yielded an unexpected phenotype, a significant increase in starch content relative to the sex6 phenotype. Amylose content (as a percentage of starch) was not increased above the level observed for the sex6 mutation alone; however, on a per seed basis, grain from lines containing the amo1 mutation (amo1 mutants and amo1sex6 double mutants) synthesize significantly more amylose than the wild-type lines and sex6 mutants. The level of granule-bound starch synthase I (GBSSI) protein in starch granules is increased in lines containing the amo1 mutation (amo1 and amo1sex6). In the amo1 genotype, starch synthase I (SSI), SSIIa, starch branching enzyme IIa (SBEIIa), and SBEIIb also markedly increased in the starch granules. Genetic mapping studies indicate that the ssIIIa gene is tightly linked to the amo1 locus, and the SSIIIa protein from the amo1 mutant has a leucine to arginine residue substitution in a conserved domain. Zymogram analysis indicates that the amo1 phenotype is not a consequence of total loss of enzymatic activity although it remains possible that the amo1 phenotype is underpinned by a more subtle change. It is therefore proposed that amo1 may be a negative regulator of other genes of starch synthesis. PMID:21813797

Physicochemical, microstructural, and antibacterial properties of β-chitosan and kudzu starch composite films.

PubMed

Zhong, Yu; Li, Yunfei; Zhao, Yanyun

2012-10-01

This study investigated physicochemical, microstructural, and antibacterial properties of β-chitosan-kudzu starch composite films with addition of 0%, 20%, 60%, or 100% kudzu starch (w starch/w chitosan) in 1% chitosan solution. Molecular interactions between chitosan and kudzu starch and the crystal structure of the films were also determined. Adding 60% kudzu starch reduced water vapor permeability and solubility of pure β-chitosan film by about 15% and 20%, respectively, whereas mechanical strength and flexibility of the film were increased about 50% and 25%, respectively. Micrograph showed that β-chitosan film was totally amorphous, and the composite films generally became rougher with more starch added. Fourier transform infrared and X-ray diffraction spectra showed that the 2 film-forming components were compatible with each other. Pure β-chitosan film resulted in 9.5 and 11.5 log CFU/mL reduction in Escherichia coli and Listeria innocua based on plate count method, respectively. Addition of kudzu starch reduced the antibacterial activity of film, but still achieved 8.3 and 10.3 log CFU/mL reduction in E. coli and L. innocua, respectively when kudzu starch to chitosan weight ratio was 1:1. Reduced antibacterial activity might attribute to the interaction of amino groups in β-chitosan with the hydroxyl groups in kudzu starch. This study demonstrated that kudzu starch effectively improved water barrier of β-chitosan film, and the composite films retained strong antibacterial ability. One percent of β-chitosan containing 60% kudzu starch (w/w chitosan) composite films possessed better mechanical and water barrier properties than pure β-chitosan films, and showed strong antibacterial activity against both Gram-positive and Gram-negative bacteria. The films may be used as wraps or coatings to prolong the shelf life of different foods or other similar applications. © 2012 Institute of Food Technologists®

Effects of ruminally degradable starch levels on performance, nitrogen balance, and nutrient digestibility in dairy cows fed low corn-based starch diets.

PubMed

Luo, Guobin; Xu, Wenbin; Yang, Jinshan; Li, Yang; Zhang, Liyang; Wang, Yizhen; Lin, Cong; Zhang, Yonggen

2017-05-01

This trial was performed to examine the effects of ruminally degradable starch (RDS) levels in total mixed ration (TMR) with low corn-based starch on the milk production, whole-tract nutrient digestibility and nitrogen balance in dairy cows. Eight multiparous Holstein cows (body weight [BW]: 717±63 kg; days in milk [DIM]: 169±29) were assigned to a crossover design with two dietary treatments: a diet containing 62.3% ruminally degradable starch (% of total starch, low RDS) or 72.1% ruminally degradable starch (% of total starch, high RDS). Changes to the ruminally degradable levels were conducted by using either finely ground corn or steam-flaked corn as the starch component. The results showed that dry matter intake, milk yield and composition in dairy cows were not affected by dietary treatments. The concentration of milk urea nitrogen was lower for cows fed high RDS TMR than low RDS TMR. The whole-tract apparent digestibility of neutral detergent fiber, acid detergent fiber and crude protein decreased, and that of starch increased for cows fed high RDS TMR over those fed low RDS TMR, with no dietary effect on the whole-tract apparent digestibility of dry matter and organic matter. The proportion of urinary N excretion in N intake was lower and that of fecal N excretion in N intake was higher for cows fed high RDS TMR than those fed low RDS TMR. The N secretion in milk and the retention of N were not influenced by the dietary treatments. Total purine derivative was similar in cows fed high RDS TMR and low RDS TMR. Consequently, estimated microbial N flow to the duodenum was similar in cows fed high RDS TMR and low RDS TMR. Results of this study show that ruminally degradable starch levels can influence whole-tract nutrient digestibility and nitrogen balance in dairy cows fed low corn-based starch diets, with no influence on performance.

The Effects of Treatments on Batu Banana Flour and Percentage of Wheat Substitution on The Resistant Starch, In Vitro Starch Digestibility Content and Palatability of Cookies Made with Banana (Musa balbisiana Colla) Flour

NASA Astrophysics Data System (ADS)

Ratnasari, D.; Rustanti, N.; Arifan, F.; Afifah, DN

2018-02-01

Diabetes mellitus (DM) is the most common endocrine disease worldwide. Resistant starch is polysaccharide that is recommended for DM patient diets. One of the staple crops containing resistant starch is banana. It is the fourth most important staple crop in the world and critical for food security, best suited plant in warm, frost-free, and coastal climates area. Among banana varieties, Batu bananas (Musa balbisiana Colla) had the highest content of resistant starch (~39%), but its use as a food ingredient is limited. Inclusion of Batu banana flour into cookies manufacturing would both increase the economic value of Batu bananas and provide alternative snacks for DM patients. Here we sought to examine whether cookies made with modified Batu banana flour would be a suitable snack for DM patients. This study used a completely randomized design with two factors: substitution of Batu banana flour (25%, 50%,75%) for wheat-based flour and Batu banana flour treatment methods (no treatment, autoclaving-cooling, autoclaving-cooling-spontaneous fermentation). The resistant starch and in vitro starch digestibility levels were analyzed using two-way ANOVA and Tukey test, whereas the acceptance level was analyzed by Friedman and Wilcoxon tests. The content of resistant starch and in vitro starch digestibility of the different treatments ranged from 3.10 to 15.79% and 16.03 to 52.59%, respectively. Both factors differed significantly (p<0.05) with respect to Batu banana flour substitution, but not to processing method (p>0.05). Meanwhile, palatability in terms of color, aroma, texture, and flavor differed significantly among the different treatments and starch contents (p<0.05). Together these results show that Batu banana flour could be a promising ingredient for the production of snacks suitable for consumption by DM patients. Keywords: Batu banana, cookies, resistant starch, in vitro starch digestibility

IDENTIFICATION OF PHARMACEUTICAL EXCIPIENT BEHAVIOR OF CHICKPEA (CICER ARIETINUM) STARCH IN GLICLAZIDE IMMEDIATE RELEASE TABLETS.

PubMed

Meka, Venkata Srikanth; Yee, Phung; Sheshala, Ravi

2016-01-01

In the past few years, there are number of researchers carrying out their research on the excipients derived from polysaccharides and some of these researches show that natural excipients are comparable and can serve as an alternative to the synthetic excipients. Hence, the objectives of this research are to characterize the naturally sourced chickpea starch powder and to study the pharmaceutical excipient behavior of chickpea starch in gliclazide immediate release (IR) tablets. In this research, the binding properties of chickpea starch were compared to that of povidone, whereas the disintegrant properties of chickpea starch were compared to those of crospovidone, croscarmellose sodium and sodium starch glycolate. Flow property of chickpea starch was assessed with the measurement of bulk density, tapped density, compressibility index and angle of repose. Calibration curve for gliclazide in phosphate buffer pH 7.4 was developed. Gliclazide IR tablets were then produced with direct compression method. Physicochemical characteristics of the tablets, including thickness, tablet weight uniformity, hardness, disintegration time and friability were evaluated. Then, in vitro dissolution studies were performed by following United States Pharmacopeia (USP) dissolution method. The dissolution results were analyzed and compared with t30, t50, dissolution efficiency (DE). Lastly, drug-excipient compatibility studies, including Fourier transform infrared (FTIR) spectroscopic analysis and differential scanning calorimetric (DSC) analysis were carried out. Fair flow property was observed in the chickpea starch powder. Furthermore, the tablets produced passed all the tests in physicochemical characteristics evaluation except hardness and disintegration test. Additionally, in vitro dissolution studies show that chickpea starch acted as a disintegrant instead of a binder in gliclazide IR tablets and its disintegrant properties were comparable to those of crospovidone, croscarmellose sodium and sodium starch glycolate. Besides that, gliclazide was also compatible with the excipients used. Chickpea starch acted as a disintegrant in gliclazide IR tablets, instead of a binder. Therefore, chickpea starch can be a promising disintegrant in gliclazide IR tablets.

Physicochemical properties and in vitro digestibility of flour and starch from pea (Pisum sativum L.) cultivars.

PubMed

Chung, Hyun-Jung; Liu, Qiang

2012-01-01

Flours and isolated starches from three different cultivars (1544-8, 1658-11 and 1760-8) of pea grown under identical environmental conditions were evaluated for their physicochemical properties and in vitro digestibility. The protein content, total starch content and apparent amylose content of pea flour ranged from 24.4 to 26.3%, 48.8 to 50.2%, and 13.9 to 16.7%, respectively. In pea starches, the 1760-8 showed higher apparent amylose content and total starch content than the other cultivars. Pea starch granules were irregularly shaped, ranging from oval to round with a smooth surface. All pea starches showed C-type X-ray diffraction pattern with relative crystallinity ranging between 23.7 and 24.7%. Pea starch had only a single endothermic transition (12.1-14.2 J/g) in the DSC thermogram, whereas pea flour showed two separate endothermic transitions corresponding to starch gelatinization (4.54-4.71 J/g) and disruption of the amylose-lipid complex (0.36-0.78 J/g). In pea cultivars, the 1760-8 had significantly higher setback and final viscosity than the other cultivars in both pea flour (672 and 1170cP, respectively) and isolated starch (2901 and 4811cP). The average branch chain length of pea starches ranged from 20.1 to 20.3. The 1760-8 displayed a larger proportion of short branch chains, DP (degree of polymerization) 6-12 (21.1%), and a smaller proportion of long branch chains, DP≥37 (8.4%). The RDS, SDS and RS contents of pea flour ranged from 23.7 to 24.1%, 11.3 to 12.8%, and 13.2 to 14.8%, respectively. In pea starches, the 1760-8 showed a lower RDS content but higher SDS and RS contents. The expected glycemic index (eGI), based on the hydrolysis index, ranged from 36.9 to 37.7 and 69.8 to 70.7 for pea flour and isolated pea starch, respectively. Copyright © 2011 Elsevier B.V. All rights reserved.

Engineering Saccharomyces cerevisiae for direct conversion of raw, uncooked or granular starch to ethanol.

PubMed

Görgens, Johann F; Bressler, David C; van Rensburg, Eugéne

2015-01-01

The production of raw starch-degrading amylases by recombinant Saccharomyces cerevisiae provides opportunities for the direct hydrolysis and fermentation of raw starch to ethanol without cooking or exogenous enzyme addition. Such a consolidated bioprocess (CBP) for raw starch fermentation will substantially reduce costs associated with energy usage and commercial granular starch hydrolyzing (GSH) enzymes. The core purpose of this review is to provide comprehensive insight into the physiological impact of recombinant amylase production on the ethanol-producing yeast. Key production parameters, based on outcomes from modifications to the yeast genome and levels of amylase production, were compared to key benchmark data. In turn, these outcomes are of significance from a process point of view to highlight shortcomings in the current state of the art of raw starch fermentation yeast compared to a set of industrial standards. Therefore, this study provides an integrated critical assessment of physiology, genetics and process aspects of recombinant raw starch fermenting yeast in relation to presently used technology. Various approaches to strain development were compared on a common basis of quantitative performance measures, including the extent of hydrolysis, fermentation-hydrolysis yield and productivity. Key findings showed that levels of α-amylase required for raw starch hydrolysis far exceeded enzyme levels for soluble starch hydrolysis, pointing to a pre-requisite for excess α-amylase compared to glucoamylase for efficient raw starch hydrolysis. However, the physiological limitations of amylase production by yeast, requiring high biomass concentrations and long cultivation periods for sufficient enzyme accumulation under anaerobic conditions, remained a substantial challenge. Accordingly, the fermentation performance of the recombinant S. cerevisiae strains reviewed in this study could not match the performance of conventional starch fermentation processes, based either on starch cooking and/or exogenous amylase enzyme addition. As an alternative strategy, the addition of exogenous GSH enzymes during early stages of raw starch fermentation may prove to be a viable approach for industrial application of recombinant S. cerevisiae, with the process still benefitting from amylase production by CBP yeast during later stages of cultivation.

Relationships between dry matter content, ensiling, ammonia-nitrogen, and ruminal in vitro starch digestibility in high-moisture corn samples.

PubMed

Ferraretto, L F; Taysom, K; Taysom, D M; Shaver, R D; Hoffman, P C

2014-05-01

The objectives of the study were (1) to determine relationships between high-moisture corn (HMC) dry matter (DM), ammonia-N [% of crude protein (CP)], and soluble CP concentrations, and pH, with 7-h ruminal in vitro starch digestibility (ivStarchD), and (2) to evaluate the effect of ensiling on pH, ammonia-N, soluble CP, and ivStarchD measurements in HMC. A data set comprising 6,131 HMC samples (55 to 80% DM) obtained from a commercial feed analysis laboratory was used for this study. Month of sample submittal was assumed to be associated with length of the ensiling period. Data for month of sample submittal were analyzed using Proc Mixed in SAS (SAS Institute Inc., Cary, NC) with month as a fixed effect. Regressions to determine linear and quadratic relationships between ivStarchD and ammonia-N, soluble CP, pH, and DM content were performed using Proc Mixed. The ivStarchD increased by 9 percentage units from October to August of the following year. Similar results were observed for ammonia-N and soluble CP with increases from 1.8 to 4.6% of CP and 31.3 to 46.4% of CP, respectively, from October to August of the following year. Ammonia-N was positively related to ivStarchD (R(2)=0.61). The DM content of HMC at silo removal was negatively related (R(2)=0.47) to ivStarchD with a decrease of 1.6 percentage units in ivStarchD per 1-percentage-unit increase in DM content. The pH of HMC was negatively related to ammonia-N (R(2)=0.53), soluble CP (R(2)=0.57), and ivStarchD (R(2)=0.51). Combined, ammonia-N, DM, soluble CP, and pH provided a good prediction of ivStarchD (adjusted R(2)=0.70). Increasing pH, ammonia-N, soluble CP, and ivStarchD values indicate that HMC may need up to 10 mo of ensiling to reach maximum starch digestibility. Ammonia-N, DM content, soluble CP concentration, and pH are good indicators of ruminal in vitro starch digestibility for high-moisture corn. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Long-term effect of resistant starch on cancer risk in carriers of hereditary colorectal cancer: an analysis from the CAPP2 randomised controlled trial.

PubMed

Mathers, John C; Movahedi, Mohammad; Macrae, Finlay; Mecklin, Jukka-Pekka; Moeslein, Gabriela; Olschwang, Sylviane; Eccles, Diana; Evans, Gareth; Maher, Eamonn R; Bertario, Lucio; Bisgaard, Marie-Luise; Dunlop, Malcolm; Ho, Judy W C; Hodgson, Shirley; Lindblom, Annika; Lubinski, Jan; Morrison, Patrick J; Murday, Victoria; Ramesar, Raj; Side, Lucy; Scott, Rodney J; Thomas, Huw J W; Vasen, Hans; Gerdes, Anne-Marie; Barker, Gail; Crawford, Gillian; Elliott, Faye; Pylvanainen, Kirsi; Wijnen, Juul; Fodde, Riccardo; Lynch, Henry; Bishop, D Timothy; Burn, John

2012-12-01

Observational studies report that higher intake of dietary fibre (a heterogeneous mix including non-starch polysaccharides and resistant starches) is associated with reduced risk of colorectal cancer, but no randomised trials with prevention of colorectal cancer as a primary endpoint have been done. We assessed the effect of resistant starch on the incidence of colorectal cancer. In the CAPP2 study, individuals with Lynch syndrome were randomly assigned in a two-by-two factorial design to receive 600 mg aspirin or aspirin placebo or 30 g resistant starch or starch placebo, for up to 4 years. Randomisation was done with a block size of 16. Post-intervention, patients entered into double-blind follow-up; participants and investigators were masked to treatment allocation. The primary endpoint for this analysis was development of colorectal cancer in participants randomly assigned to resistant starch or resistant-starch placebo with both intention-to-treat and per-protocol analyses. This study is registered, ISRCTN 59521990. 463 patients were randomly assigned to receive resistant starch and 455 to receive resistant-starch placebo. At a median follow-up 52·7 months (IQR 28·9-78·4), 53 participants developed 61 primary colorectal cancers (27 of 463 participants randomly assigned to resistant starch, 26 of 455 participants assigned to resistant-starch placebo). Intention-to-treat analysis of time to first colorectal cancer showed a hazard ratio (HR) of 1·40 (95% CI 0·78-2·56; p=0·26) and Poisson regression accounting for multiple primary events gave an incidence rate ratio (IRR) of 1·15 (95% CI 0·66-2·00; p=0·61). For those completing 2 years of intervention, per-protocol analysis yielded a HR of 1·09 (0·55-2·19, p=0·80) and an IRR of 0·98 (0·51-1·88, p=0·95). No information on adverse events was gathered during post-intervention follow-up. Resistant starch had no detectable effect on cancer development in carriers of hereditary colorectal cancer. Dietary supplementation with resistant starch does not emulate the apparently protective effect of diets rich in dietary fibre against colorectal cancer. European Union, Cancer Research UK, Bayer Corporation, National Starch and Chemical Co, UK Medical Research Council, Newcastle Hospitals Trustees, Cancer Council of Victoria Australia, THRIPP South Africa, The Finnish Cancer Foundation, SIAK Switzerland, and Bayer Pharma. Copyright © 2012 Elsevier Ltd. All rights reserved.

Enhancement of photoassimilate utilization by manipulation of starch regulatory enzymes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okita, Thomas W.

ADPglucose pyrophosphorylase (AGPase) and the plastidial starch phosphorylase1 (Pho1) are two regulatory enzymes whose catalytic activities are essential for starch granule synthesis. Conversion of the pre-starch granule to the mature form is dependent on AGPase, which produces ADPglucose, the substrate used by starch synthases. The catalytic activity of AGPase is controlled by small effector molecules and a prime goal of this project was to decipher the role of the two subunit types that comprise the heterotetrameric enzyme structure. Extensive genetic and biochemical studies showed that catalysis was contributed mainly by the small subunit although the large subunit was required formore » maximum activity. Both subunits were needed for allosteric regulatory properties. We had also demonstrated that the AGPase catalyzed reaction limits the amount of starch accumulation in developing rice seeds and that carbon flux into rice seed starch can be increased by expression of a cytoplasmic-localized, up-regulated bacterial AGPase enzyme form. Results of subsequent physiological and metabolite studies showed that the AGPase reaction is no longer limiting in the AGPase transgenic rice lines and that one or more downstream processes prevent further increases in starch biosynthesis. Further studies showed that over-production of ADPglucose dramatically alters the gene program during rice seed development. Although the expression of nearly all of the genes are down-regulated, levels of a starch binding domain containing protein (SBDCP) are elevated. This SBDCP was found to bind to and inhibit the catalytic activity of starch synthase III and, thereby preventing maximum starch synthesis from occurring. Surprisingly, repression of SBDCP elevated expression of starch synthase III resulting in increasing rice grain weight. A second phase of this project examined the structure-function of Pho1, the enzyme required during the initial phase of pre-starch granule formation and its maturation to a starch granule. Although Pho1 catalyzes a reversible reaction, our DoE supported studies clearly demonstrated that the kinetic properties of this enzyme strongly favor synthesis of starch and that these catalytic properties are independent of the L80 peptide, a structural domain that is absent in phosphorylases from other organisms. Interesting expression of a Pho1 lacking the L80 peptide enhanced plant growth and seed yields, suggesting that Pho1 has a second function in controlling growth. Overall, results from these biochemical and physiological studies have increased our fundamental understanding on how these important starch regulatory enzymes operate at the molecular level and in planta, which will collectively aid in efforts to increase the utilization of higher plants as a renewable source of energy.« less

Effect of dietary starch concentration and fish oil supplementation on milk yield and composition, diet digestibility, and methane emissions in lactating dairy cows.

PubMed

Pirondini, M; Colombini, S; Mele, M; Malagutti, L; Rapetti, L; Galassi, G; Crovetto, G M

2015-01-01

The aim of this study was to evaluate the effects of diets with different starch concentrations and fish oil (FO) supplementation on lactation performance, in vivo total-tract nutrient digestibility, N balance, and methane (CH4) emissions in lactating dairy cows. The experiment was conducted as a 4×4 Latin square design with a 2×2 factorial arrangement: 2 concentrations of dietary starch [low vs. high: 23.7 and 27.7% on a dry matter (DM) basis; neutral detergent fiber/starch ratios: 1.47 and 1.12], the presence or absence of FO supplement (0.80% on a DM basis), and their interaction were evaluated. Four Italian Friesian cows were fed 1 of the following 4 diets in 4 consecutive 26-d periods: (1) low starch (LS), (2) low starch plus FO (LSO), (3) high starch (HS), and (4) high starch plus FO (HSO). The diets contained the same amount of forages (corn silage, alfalfa and meadow hays). The starch concentration was balanced using different proportions of corn meal and soybean hulls. The cows were housed in metabolic stalls inside open-circuit respiration chambers to allow measurement of CH4 emission and the collection of separate urine and feces. No differences among treatments were observed for DM intake. We observed a trend for FO to increase milk yield: 29.2 and 27.5kg/d, on average, for diets with and without FO, respectively. Milk fat was affected by the interaction between dietary starch and FO: milk fat decreased only in the HSO diet. Energy-corrected milk (ECM) was affected by the interaction between starch and FO, with a positive effect of FO on the LS diet. Fish oil supplementation decreased the n-6:n-3 ratio of milk polyunsaturated fatty acids. High-starch diets negatively influenced all digestibility parameters measured except starch, whereas FO improved neutral detergent fiber digestibility (41.9 vs. 46.1% for diets without and with FO, respectively, and ether extract digestibility (53.7 vs. 67.1% for diets without and with FO, respectively). We observed a trend for lower CH4 emission (g/d) and intensity (g/kg of milk) with the high-starch diets compared with the low-starch diets: 396 versus 415g/d on average, respectively, and 14.1 versus 14.9g/kg of milk, respectively. Methane intensity per kilogram of ECM was affected by the interaction between starch and FO, with a positive effect of FO for the LS diet: 14.5 versus 13.3g of CH4/kg of ECM for LS and LSO diets, respectively. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Resistant Starch and Starch Thermal Characteristics in Exotic Corn Lines Grown in Temperate and Tropical Environments

USDA-ARS?s Scientific Manuscript database

Corn as a food that is heated and cooled to allow starch retrogradation has higher levels of resistant starch (RS). Increasing the amount of RS can make corn an even healthier food and may be accomplished by breeding and selection, especially by using exotic germplasm. Sixty breeding lines of introg...

Effects of growing environment and cooking methods on resistant starch content of high amylose rice varieties

USDA-ARS?s Scientific Manuscript database

Resistant starch (RS), a type of fermentable dietary fiber, has potential to improve colon health and decrease cardiovascular disease risk factors. It is defined as the fraction of the starch and the products of starch degradation that resist digestion in the small intestines of healthy humans and i...

21 CFR 184.1277 - Dextrin.

Code of Federal Regulations, 2014 CFR

2014-04-01

....1277 Dextrin. (a) Dextrin ((C6H10O5)n·H2O, CAS Reg. No. 9004-53-9) is an incompletely hydrolyzed starch..., or sago starches, or by dry heating the starches after: (1) Treatment with safe and suitable alkalis, acids, or pH control agents and (2) drying the acid or alkali treated starch. (b) The ingredient meets...

76 FR 14970 - National Starch and Chemical Company, Salisbury, Rowan County, NC; Notice of Settlement

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-18

... ENVIRONMENTAL PROTECTION AGENCY [Docket EPA-RO4-SFUND-2011-0278, FRL-9284-1] National Starch and... entered into a settlement for reimbursement of past response costs concerning the National Starch and... No. EPA-RO4- SFUND-2011-0278 or Site name National Starch and Chemical Company Superfund Site by one...

76 FR 19096 - National Starch and Chemical Company, Salisbury, Rowan County, North Carolina; Notice of Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-06

... ENVIRONMENTAL PROTECTION AGENCY [Docket EPA-RO4-SFUND-2011-0278, FRL-9290-7] National Starch and... National Starch and Chemical Company Site located in Salisbury, Rowan County, North Carolina. In the...- SFUND-2011-0278 or Site name National Starch and Chemical Company Superfund Site by one of the following...

Extrusion of rice, bean, and corn starches: extrudate structure and molecular changes in amylose and amylopectin

USDA-ARS?s Scientific Manuscript database

This study evaluated the effects of starch source and amylose content on expansion ratio, density and texture of expanded extrudates, as well as the structural and molecular changes that occurred in starch granules as a function of extrusion. Rice starches (8%, 20% and 32% amylose), carioca bean sta...

Effects of corn fiber gum (CFG) on the pasting and thermal behaviors of maize starch

USDA-ARS?s Scientific Manuscript database

Corn fiber gum (CFG) is a novel arabinoxylan hydrocolloid. Recent research showed its considerable potential in food processing. In this study, the interactions of maize starch and CFG were studied. Maize starch/CFG blend gels were prepared from maize starch suspension mixed with 0.1%, 0.25%, 0.5%, ...

Characterizations of substrate and enzyme specificity of glucoamylase assays of mucosal starch digestion with determinations of group and single biopsy reference values

USDA-ARS?s Scientific Manuscript database

Carbohydrate digesting enzyme activities are measured in duodenal biopsies to detect deficiencies of lactase and sucrase activities, however glucoamylase (GA) assays for starch digestion are not included. Because food starch represents half of energy intake in the human diet, assays for starch diges...

Creation of a high-amylose durum wheat through mutagenesis of starch synthase II (SSIIa)

USDA-ARS?s Scientific Manuscript database

In cereal seeds mutations in one or more starch synthases lead to decreased amylopectin and increased amylose content. Here, the impact of starch synthase IIa (SSIIa or SGP-1) mutations upon durum starch was investigated. A screen of durum accessions identified two lines lacking SGP-A1, the A geno...

Characterisation of a starch-hydrolysing enzyme of Aspergillus niger.

PubMed

Suresh, C; Dubey, A K; Srikanta, S; Kumar, S U; Karanth, N G

1999-05-01

A UV-induced mutant strain of Aspergillus niger (CFTRI-1105-U9) overproduced a starch-hydrolysing enzyme with properties characteristically different from the known amylases of the fungus. The purified enzyme of 4.0 pI had an apparent molecular mass of 125 kDa and it dextrinised starch and then saccharified the dextrins. Patterns of the enzyme activity on starch, resulting in glucose at 60 degrees C and glucose, maltose and maltodextrins at 70 degrees C as primary products, suggested significant applications for the enzyme in starch-processing industries.

Changes in resistant starch from two banana cultivars during postharvest storage.

PubMed

Wang, Juan; Tang, Xue Juan; Chen, Ping Sheng; Huang, Hui Hua

2014-08-01

Banana resistant starch samples were extracted and isolated from two banana cultivars (Musa AAA group, Cavendish subgroup and Musa ABB group, Pisang Awak subgroup) at seven ripening stages during postharvest storage. The structures of the resistant starch samples were analysed by light microscopy, polarising microscopy, scanning electron microscopy, X-ray diffraction, and infrared spectroscopy. Physicochemical properties (e.g., water-holding capacity, solubility, swelling power, transparency, starch-iodine absorption spectrum, and Brabender microviscoamylograph profile) were determined. The results revealed significant differences in microstructure and physicochemical characteristics among the banana resistant starch samples during different ripening stages. The results of this study provide valuable information for the potential applications of banana resistant starches. Copyright © 2014 Elsevier Ltd. All rights reserved.

Step-reduced synthesis of starch-silver nanoparticles.

PubMed

Raghavendra, Gownolla Malegowd; Jung, Jeyoung; Kim, Dowan; Seo, Jongchul

2016-05-01

In the present process, silver nanoparticles were directly synthesized in a single step by microwave irradiation of a mixture of starch, silver nitrate, and deionized water. This is different from the commonly adopted procedure for starch-silver nanoparticle synthesis in which silver nanoparticles are synthesized by preparing a starch solution as a reaction medium first. Thus, the additional step associated with the preparation of the starch solution was eliminated. In addition, no additional reducing agent was utilized. The adopted method was facile and straight forward, affording spherical silver nanoparticles with diameter below 10nm that exhibited good antibacterial activity. Further, influence of starch on the size of the silver nanoparticles was noticed. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparative physico-chemical profiles of Tugaksheeree (Curcuma angustifolia Roxb. and Maranta arundinacea Linn.).

PubMed

Rajashekhara, N; Shukla, Vinay J; Ravishankar, B; Sharma, Parameshwar P

2013-10-01

Tugaksheeree is as an ingredient in many Ayurvedic formulations. The starch obtained from the rhizomes of two plants, is used as Tugaksheeree, Curcuma angustifolia (CA) Roxb. (Family: Zingiberaceae) and Maranta arundinacea (MA) Linn. (Family Marantaceae). In the present study, a comparative physico-analysis of both the drugs has been carried out. The results suggest that the starch from CA and MA has similar organoleptic characters. The percentage of starch content is higher in the rhizome of CA when compared with that of MA and the starch of MA is packed more densely than the starch in CA. The chemical constituents of both the starch and rhizomes are partially similar to each other. Hence, the therapeutic activities may be similar.

Hypolipidaemic effect of maize starch with different amylose content in ovariectomized rats depends on intake amount of resistant starch.

PubMed

Liu, Xiong; Ogawa, Hiroshi; Kishida, Taro; Ebihara, Kiyoshi

2009-02-01

The effect of amylose content on digestibility of starch in the small intestine and on the concentration of plasma lipid were studied in ileorectostomized rats and in ovariectomized rats, respectively. Seven kinds of starch with different amylose content (0, 27, 54, 62, 76, 79, 86 %) were used as test starch, which contained 0.4, 5.6, 37.1, 40.2, 45.6, 36.9 and 36.1 % resistant starch (RS), respectively. Rats were fed one of test diets containing 30 % test starch with different amylose content for 14 d in ileorectostomized and for 21 d in ovariectomized rats. Food intake was not significantly different among the groups. In ileorectostomized rats, the small intestinal starch digestibility decreased with increasing intakes of amylose and RS. In ovariectomized rats, body weight gain was lower on the higher amylose maize starch diets. The concentrations of plasma TAG and cholesterol decreased with increasing intake of RS. The concentrations of liver total lipids and TAG decreased with increasing intake of RS, but that of liver cholesterol did not. There was significant positive correlation between the level of sterol regulatory element-binding protein-1c mRNA and concentration of liver TAG. Total SCFA amount in the caecum increased logarithmically with increasing dry weight of caecal contents. The amount of bile acids in the small intestinal content and the excretions of bile acids and neutral steroids in faeces increased with increasing RS intake. These results show that starch rich in RS is more effective in preventing ovarian hormone deficiency-induced hyperlipidaemia.

Reduction of the plastidial phosphorylase in potato (Solanum tuberosum L.) reveals impact on storage starch structure during growth at low temperature.

PubMed

Orawetz, Tom; Malinova, Irina; Orzechowski, Slawomir; Fettke, Joerg

2016-03-01

Tubers of potato (Solanum tuberosum L.), one of the most important crops, are a prominent example for an efficient production of storage starch. Nevertheless, the synthesis of this storage starch is not completely understood. The plastidial phosphorylase (Pho1; EC 2.4.1.1) catalyzes the reversible transfer of glucosyl residues from glucose-1-phosphate to the non-reducing end of α-glucans with the release of orthophosphate. Thus, the enzyme is in principle able to act during starch synthesis. However, so far under normal growth conditions no alterations in tuber starch metabolism were observed. Based on analyses of other species and also from in vitro experiments with potato tuber slices it was supposed, that Pho1 has a stronger impact on starch metabolism, when plants grow under low temperature conditions. Therefore, we analyzed the starch content, granule size, as well as the internal structure of starch granules isolated from potato plants grown under low temperatures. Besides wild type, transgenic potato plants with a strong reduction in the Pho1 activity were analyzed. No significant alterations in starch content and granule size were detected. In contrast, when plants were cultivated at low temperatures the chain length distributions of the starch granules were altered. Thus, the granules contained more short glucan chains. That was not observed in the transgenic plants, revealing that Pho1 in wild type is involved in the formation of the short glucan chains, at least at low temperatures. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Lineage-Specific Evolutionary Histories and Regulation of Major Starch Metabolism Genes during Banana Ripening

PubMed Central

Jourda, Cyril; Cardi, Céline; Gibert, Olivier; Giraldo Toro, Andrès; Ricci, Julien; Mbéguié-A-Mbéguié, Didier; Yahiaoui, Nabila

2016-01-01

Starch is the most widespread and abundant storage carbohydrate in plants. It is also a major feature of cultivated bananas as it accumulates to large amounts during banana fruit development before almost complete conversion to soluble sugars during ripening. Little is known about the structure of major gene families involved in banana starch metabolism and their evolution compared to other species. To identify genes involved in banana starch metabolism and investigate their evolutionary history, we analyzed six gene families playing a crucial role in plant starch biosynthesis and degradation: the ADP-glucose pyrophosphorylases (AGPases), starch synthases (SS), starch branching enzymes (SBE), debranching enzymes (DBE), α-amylases (AMY) and β-amylases (BAM). Using comparative genomics and phylogenetic approaches, these genes were classified into families and sub-families and orthology relationships with functional genes in Eudicots and in grasses were identified. In addition to known ancestral duplications shaping starch metabolism gene families, independent evolution in banana and grasses also occurred through lineage-specific whole genome duplications for specific sub-families of AGPase, SS, SBE, and BAM genes; and through gene-scale duplications for AMY genes. In particular, banana lineage duplications yielded a set of AGPase, SBE and BAM genes that were highly or specifically expressed in banana fruits. Gene expression analysis highlighted a complex transcriptional reprogramming of starch metabolism genes during ripening of banana fruits. A differential regulation of expression between banana gene duplicates was identified for SBE and BAM genes, suggesting that part of starch metabolism regulation in the fruit evolved in the banana lineage. PMID:27994606

Eukaryotic starch degradation: integration of plastidial and cytosolic pathways.

PubMed

Fettke, Joerg; Hejazi, Mahdi; Smirnova, Julia; Höchel, Erik; Stage, Marion; Steup, Martin

2009-01-01

Starch is an important plant product widely used as a nutrient, as a source of renewable energy, and for many technological applications. In plants, starch is the almost ubiquitous storage carbohydrate whereas most heterotrophic prokaryotes and eukaryotes rely on glycogen. Despite close similarities in basic chemical features, starch and glycogen differ in both structural and physicochemical properties. Glycogen is a hydrosoluble macromolecule with evenly distributed branching points. Starch exists as a water-insoluble particle having a defined (and evolutionary conserved) internal structure. The biochemistry of starch requires the co-operation of up to 40 distinct (iso)enzymes whilst approximately 10 (iso)enzymes permit glycogen metabolism. The biosynthesis and degradation of native starch include the transition of carbohydrates from the soluble to the solid phase and vice versa. In this review, two novel aspects of the eukaryotic plastidial starch degradation are discussed: Firstly, biochemical reactions that take place at the surface of particulate glucans and mediate the phase transition of carbohydrates. Secondly, processes that occur downstream of the export of starch-derived sugars into the cytosol. Degradation of transitory starch mainly results in the formation of neutral sugars, such as glucose and maltose, that are transported into the cytosol via the respective translocators. The cytosolic metabolism of the neutral sugars includes the action of a hexokinase, a phosphoglucomutase, and a transglucosidase that utilizes high molecular weight glycans as a transient glucosyl acceptor or donor. Data are included on the transglucosidase (disproportionating isozyme 2) in Cyanophora paradoxa that accumulates storage carbohydrates in the cytosol rather than in the plastid.

Hot-melt extrusion of sugar-starch-pellets.

PubMed

Yeung, Chi-Wah; Rein, Hubert

2015-09-30

Sugar-starch-pellets (syn. sugar spheres) are usually manufactured through fluidized bed granulation or wet extrusion techniques. This paper introduces hot-melt extrusion (HME) as an alternative method to manufacture sugar-starch-pellets. A twin-screw extruder coupled with a Leistritz Micro Pelletizer (LMP) cutting machine was utilized for the extrusion of different types (normal-, waxy-, and high-amlyose) of corn starch, blended with varying amounts of sucrose. Pellets were characterized for their physicochemical properties including crystallinity, particle size distribution, tensile strength, and swelling expansion. Furthermore, the influence of sugar content and humidity on the product was investigated. Both sucrose and water lowered the Tg of the starch system allowing a convenient extrusion process. Mechanical strength and swelling behavior could be associated with varying amylose and amylopectin. X-ray powder diffractometric (XRPD) peaks of increasing sucrose contents appeared above 30%. This signified the oversaturation of the extruded starch matrix system with sucrose. Otherwise, had the dissolved sucrose been embedded into the molten starch matrix, no crystalline peak could have been recognized. The replacement of starch with sucrose reduced the starch pellets' swelling effect, which resulted in less sectional expansion (SEI) and changed the surface appearance. Further, a nearly equal tensile strength could be detected for sugar spheres with more than 40% sucrose. This observation stands in good relation with the analyzed values of the commercial pellets. Both techniques (fluidized bed and HME) allowed a high yield of spherical pellets (less friability) for further layering processes. Thermal influence on the sugar-starch system is still an obstacle to be controlled. Copyright © 2015 Elsevier B.V. All rights reserved.

Most of ADP·glucose linked to starch biosynthesis occurs outside the chloroplast in source leaves

PubMed Central

Baroja-Fernández, Edurne; Muñoz, Francisco José; Zandueta-Criado, Aitor; Morán-Zorzano, María Teresa; Viale, Alejandro Miguel; Alonso-Casajús, Nora; Pozueta-Romero, Javier

2004-01-01

Sucrose and starch are end products of two segregated gluconeogenic pathways, and their production takes place in the cytosol and chloroplast of green leaves, respectively. According to this view, the plastidial ADP·glucose (ADPG) pyrophosphorylase (AGP) is the sole enzyme catalyzing the synthesis of the starch precursor molecule ADPG. However, a growing body of evidences indicates that starch formation involves the import of cytosolic ADPG to the chloroplast. This evidence is consistent with the idea that synthesis of the ADPG linked to starch biosynthesis takes place in the cytosol by means of sucrose synthase, whereas AGP channels the glucose units derived from the starch breakdown. To test this hypothesis, we first investigated the subcellular localization of ADPG. Toward this end, we constructed transgenic potato plants that expressed the ADPG-cleaving adenosine diphosphate sugar pyrophosphatase (ASPP) from Escherichia coli either in the chloroplast or in the cytosol. Source leaves from plants expressing ASPP in the chloroplast exhibited reduced starch and normal ADPG content as compared with control plants. Most importantly however, leaves from plants expressing ASPP in the cytosol showed a large reduction of the levels of both ADPG and starch, whereas hexose phosphates increased as compared with control plants. No pleiotropic changes in photosynthetic parameters and maximum catalytic activities of enzymes closely linked to starch and sucrose metabolism could be detected in the leaves expressing ASPP in the cytosol. The overall results show that, essentially similar to cereal endosperms, most of the ADPG linked to starch biosynthesis in source leaves occurs in the cytosol. PMID:15326306

Advanced water splitting for green hydrogen gas production through complete oxidation of starch by in vitro metabolic engineering.

PubMed

Kim, Jae-Eung; Kim, Eui-Jin; Chen, Hui; Wu, Chang-Hao; Adams, Michael W W; Zhang, Y-H Percival

2017-11-01

Starch is a natural energy storage compound and is hypothesized to be a high-energy density chemical compound or solar fuel. In contrast to industrial hydrolysis of starch to glucose, an alternative ATP-free phosphorylation of starch was designed to generate cost-effective glucose 6-phosphate by using five thermophilic enzymes (i.e., isoamylase, alpha-glucan phosphorylase, 4-α-glucanotransferase, phosphoglucomutase, and polyphosphate glucokinase). This enzymatic phosphorolysis is energetically advantageous because the energy of α-1,4-glycosidic bonds among anhydroglucose units is conserved in the form of phosphorylated glucose. Furthermore, we demonstrated an in vitro 17-thermophilic enzyme pathway that can convert all glucose units of starch, regardless of branched and linear contents, with water to hydrogen at a theoretic yield (i.e., 12 H 2 per glucose), three times of the theoretical yield from dark microbial fermentation. The use of a biomimetic electron transport chain enabled to achieve a maximum volumetric productivity of 90.2mmol of H 2 /L/h at 20g/L starch. The complete oxidation of starch to hydrogen by this in vitro synthetic (enzymatic) biosystem suggests that starch as a natural solar fuel becomes a high-density hydrogen storage compound with a gravimetric density of more than 14% H 2 -based mass and an electricity density of more than 3000Wh/kg of starch. Copyright © 2017. Published by Elsevier Inc.

The "Food Polymer Science" approach to the practice of industrial R&D, leading to patent estates based on fundamental starch science and technology.

PubMed

Slade, Louise; Levine, Harry

2018-04-13

This article reviews the application of the "Food Polymer Science" approach to the practice of industrial R&D, leading to patent estates based on fundamental starch science and technology. The areas of patents and patented technologies reviewed here include: (a) soft-from-the-freezer ice creams and freezer-storage-stable frozen bread dough products, based on "cryostabilization technology" of frozen foods, utilizing commercial starch hydrolysis products (SHPs); (b) glassy-matrix encapsulation technology for flavors and other volatiles, based on structure-function relationships for commercial SHPs; (c) production of stabilized whole-grain wheat flours for biscuit products, based on the application of "solvent retention capacity" technology to develop flours with reduced damaged starch; (d) production of improved-quality, low-moisture cookies and crackers, based on pentosanase enzyme technology; (e) production of "baked-not-fried," chip-like, starch-based snack products, based on the use of commercial modified-starch ingredients with selected functionality; (f) accelerated staling of a starch-based food product from baked bread crumb, based on the kinetics of starch retrogradation, treated as a crystallization process for a partially crystalline glassy polymer system; and (g) a process for producing an enzyme-resistant starch, for use as a reduced-calorie flour replacer in a wide range of grain-based food products, including cookies, extruded expanded snacks, and breakfast cereals.

Effect of cooling of cooked white rice on resistant starch content and glycemic response.

PubMed

Sonia, Steffi; Witjaksono, Fiastuti; Ridwan, Rahmawati

2015-01-01

Cooling of cooked starch is known to cause starch retrogradation which increases resistant starch content. This study aimed to determine the effect of cooling of cooked white rice on resistant starch content and glycemic response in healthy subjects. Resistant starch contents were analyzed on freshly cooked white rice (control rice), cooked white rice cooled for 10 hours at room temperature (test rice I), and cooked white rice cooled for 24 hours at 4°C then reheated (test rice II). The results showed that resistant starch contents in control rice, test rice I, and test rice II were 0.64 g/100 g, 1.30 g/100 g, and 1.65 g/100 g, respectively. Test rice II had higher resistant starch content than test rice I, hence used in the clinical study along with control rice to characterize glycemic response in 15 healthy adults. The clinical study was a randomized, single-blind crossover study. In the clinical study, test rice II significantly lowered glycemic response compared with control rice (125±50.1 vs 152±48.3 mmol.min/L, respectively; p=0.047). In conclusion, cooling of cooked white rice increased resistant starch content. Cooked white rice cooled for 24 hours at 4°C then reheated lowered glycemic response compared with freshly cooked white rice.

In vitro starch digestibility, pasting and textural properties of mung bean: effect of different processing methods.

PubMed

Kaur, Maninder; Sandhu, Kawaljit Singh; Ahlawat, RavinderPal; Sharma, Somesh

2015-03-01

Mung bean was subjected to different processing conditions (soaking, germination, cooking and autoclaving) and their textural, pasting and in vitro starch digestibility characteristics were studied. A significant reduction in textural properties (hardness, cohesiveness, gumminess and chewiness) after cooking and autoclaving treatment of mung bean was observed. Flours made from differently processed mung bean showed significant differences (P < 0.05) in their pastin g characteristics. Peak and final viscosity were the highest for flour from germinated mung bean whereas those made from autoclaved mung bean showed the lowest value. in vitro starch digestibility of mung bean flours was assessed enzymatically using modified Englyst method and the parameters studied were readily digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS) and total starch (TS) content. Various processing treatments increased the RDS contents of mung bean, while the SDS content was found to be the highest for soaked and the lowest for the autoclaved sample. Germinated sample showed higher amount of digestible starch (RDS + SDS) as compared to raw and soaked samples. Flours from raw and soaked samples showed significantly low starch hydrolysis rate at all the temperatures with total hydrolysis of 29.9 and 31.2 %, respectively at 180 min whereas cooked and autoclaved samples showed high hydrolysis rates with 50.2 and 53.8 % of these hydrolyzing within 30 min of hydrolysis.

Structure of the Arabidopsis Glucan Phosphatase LIKE SEX FOUR2 Reveals a Unique Mechanism for Starch Dephosphorylation[W

PubMed Central

Meekins, David A.; Guo, Hou-Fu; Husodo, Satrio; Paasch, Bradley C.; Bridges, Travis M.; Santelia, Diana; Kötting, Oliver; Vander Kooi, Craig W.; Gentry, Matthew S.

2013-01-01

Starch is a water-insoluble, Glc-based biopolymer that is used for energy storage and is synthesized and degraded in a diurnal manner in plant leaves. Reversible phosphorylation is the only known natural starch modification and is required for starch degradation in planta. Critical to starch energy release is the activity of glucan phosphatases; however, the structural basis of dephosphorylation by glucan phosphatases is unknown. Here, we describe the structure of the Arabidopsis thaliana starch glucan phosphatase LIKE SEX FOUR2 (LSF2) both with and without phospho-glucan product bound at 2.3Å and 1.65Å, respectively. LSF2 binds maltohexaose-phosphate using an aromatic channel within an extended phosphatase active site and positions maltohexaose in a C3-specific orientation, which we show is critical for the specific glucan phosphatase activity of LSF2 toward native Arabidopsis starch. However, unlike other starch binding enzymes, LSF2 does not possess a carbohydrate binding module domain. Instead we identify two additional glucan binding sites located within the core LSF2 phosphatase domain. This structure is the first of a glucan-bound glucan phosphatase and provides new insights into the molecular basis of this agriculturally and industrially relevant enzyme family as well as the unique mechanism of LSF2 catalysis, substrate specificity, and interaction with starch granules. PMID:23832589

Starch as a source, starch as a sink: the bifunctional role of starch in carbon allocation.

PubMed

MacNeill, Gregory J; Mehrpouyan, Sahar; Minow, Mark A A; Patterson, Jenelle A; Tetlow, Ian J; Emes, Michael J

2017-07-20

Starch commands a central role in the carbon budget of the majority of plants on earth, and its biological role changes during development and in response to the environment. Throughout the life of a plant, starch plays a dual role in carbon allocation, acting as both a source, releasing carbon reserves in leaves for growth and development, and as a sink, either as a dedicated starch store in its own right (in seeds and tubers), or as a temporary reserve of carbon contributing to sink strength, in organs such as flowers, fruits, and developing non-starchy seeds. The presence of starch in tissues and organs thus has a profound impact on the physiology of the growing plant as its synthesis and degradation governs the availability of free sugars, which in turn control various growth and developmental processes. This review attempts to summarize the large body of information currently available on starch metabolism and its relationship to wider aspects of carbon metabolism and plant nutrition. It highlights gaps in our knowledge and points to research areas that show promise for bioengineering and manipulation of starch metabolism in order to achieve more desirable phenotypes such as increased yield or plant biomass. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Molecular Genetic Analysis of Glucan Branching Enzymes from Plants and Bacteria in Arabidopsis Reveals Marked Differences in Their Functions and Capacity to Mediate Starch Granule Formation1[OPEN

PubMed Central

Lu, Kuan-Jen; Streb, Sebastian; Meier, Florence; Pfister, Barbara; Zeeman, Samuel C.

2015-01-01

The major component of starch is the branched glucan amylopectin, the branching pattern of which is one of the key factors determining its ability to form semicrystalline starch granules. Here, we investigated the functions of different branching enzyme (BE) types by expressing proteins from maize (Zea mays BE2a), potato (Solanum tuberosum BE1), and Escherichia coli (glycogen BE [EcGLGB]) in Arabidopsis (Arabidopsis thaliana) mutant plants that are deficient in their endogenous BEs and therefore, cannot make starch. The expression of each of these three BE types restored starch biosynthesis to differing degrees. Full complementation was achieved using the class II BE ZmBE2a, which is most similar to the two endogenous Arabidopsis isoforms. Expression of the class I BE from potato, StBE1, resulted in partial complementation and high amylose starch. Expression of the glycogen BE EcGLGB restored only minimal amounts of starch production, which had unusual chain length distribution, branch point distribution, and granule morphology. Nevertheless, each type of BE together with the starch synthases and debranching enyzmes were able to create crystallization-competent amylopectin polymers. These data add to the knowledge of how the properties of the BE influence the final composition of starch and fine structure of amylopectin. PMID:26358415

Plastidial Folate Prevents Starch Biosynthesis Triggered by Sugar Influx into Non-Photosynthetic Plastids of Arabidopsis.

PubMed

Hayashi, Makoto; Tanaka, Mina; Yamamoto, Saki; Nakagawa, Taro; Kanai, Masatake; Anegawa, Aya; Ohnishi, Miwa; Mimura, Tetsuro; Nishimura, Mikio

2017-08-01

Regulation of sucrose-starch interconversion in plants is important to maintain energy supplies necessary for viability and growth. Arabidopsis mutants were screened for aberrant responses to sucrose to identify candidates with a defect in the regulation of starch biosynthesis. One such mutant, fpgs1-4, accumulated substantial amounts of starch in non-photosynthetic cells. Dark-grown mutant seedlings exhibited shortened hypocotyls and accumulated starch in etioplasts when supplied with exogenous sucrose/glucose. Similar starch accumulation from exogenous sucrose was observed in mutant chloroplasts, when photosynthesis was prevented by organ culture in darkness. Molecular genetic analyses revealed that the mutant was defective in plastidial folylpolyglutamate synthetase, one of the enzymes engaged in folate biosynthesis. Active folate derivatives are important biomolecules that function as cofactors for a variety of enzymes. Exogenously supplied 5-formyl-tetrahydrofolate abrogated the mutant phenotypes, indicating that the fpgs1-4 mutant produced insufficient folate derivative levels. In addition, the antifolate agents methotrexate and 5-fluorouracil induced starch accumulation from exogenously supplied sucrose in dark-grown seedlings of wild-type Arabidopsis. These results indicate that plastidial folate suppresses starch biosynthesis triggered by sugar influx into non-photosynthetic cells, demonstrating a hitherto unsuspected link between plastidial folate and starch metabolism. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

The effect of pH on hydrolysis, cross-linking and barrier properties of starch barriers containing citric acid.

PubMed

Olsson, Erik; Menzel, Carolin; Johansson, Caisa; Andersson, Roger; Koch, Kristine; Järnström, Lars

2013-11-06

Citric acid cross-linking of starch for e.g. food packaging applications has been intensely studied during the last decade as a method of producing water-insensitive renewable barrier coatings. We managed to improve a starch formulation containing citric acid as cross-linking agent for industrial paper coating applications by adjusting the pH of the starch solution. The described starch formulations exhibited both cross-linking of starch by citric acid as well as satisfactory barrier properties, e.g. fairly low OTR values at 50% RH that are comparable with EVOH. Furthermore, it has been shown that barrier properties of coated papers with different solution pH were correlated to molecular changes in starch showing both hydrolysis and cross-linking of starch molecules in the presence of citric acid. Hydrolysis was shown to be almost completely hindered at solution pH≥4 at curing temperatures≤105 °C and at pH≥5 at curing temperatures≤150 °C, whereas cross-linking still occurred to some extent at pH≤6.5 and drying temperatures as low as 70 °C. Coated papers showed a minimum in water vapor transmission rate at pH 4 of the starch coating solution, corresponding to the point where hydrolysis was effectively hindered but where a significant degree of cross-linking still occurred. Copyright © 2013 Elsevier Ltd. All rights reserved.

Molecular, mesoscopic and microscopic structure evolution during amylase digestion of extruded maize and high amylose maize starches.

PubMed

Shrestha, Ashok K; Blazek, Jaroslav; Flanagan, Bernadine M; Dhital, Sushil; Larroque, Oscar; Morell, Matthew K; Gilbert, Elliot P; Gidley, Michael J

2015-03-15

Extrusion processing of cereal starch granules with high (>50%) amylose content is a promising approach to create nutritionally desirable resistant starch, i.e. starch that escapes digestion in the small intestine. Whilst high amylose content seems to be required, the structural features responsible for the slow digestion of extrudates are not fully understood. We report the effects of partial enzyme digestion of extruded maize starches on amylopectin branch length profiles, double and single helix contents, crystallinity and lamellar periodicity. Comparing results for three extruded maize starches (27, 57, and 84% apparent amylose) that differ in amylase-sensitivity allows conclusions to be drawn concerning the rate-determining features operating under the digestion conditions used. Enzyme resistance is shown to originate from a combination of molecular and mesoscopic factors, including both recrystallization and an increase in very short branches during the digestion process. This is in contrast to the behaviour of the same starches in the granular form (Shrestha et al., 2012) where molecular and mesoscopic factors are secondary to microscopic structures in determining enzyme susceptibility. Based on the structure of residual material after long-time digestion (>8h), a model for resistant starch from processed high amylose maize starches is proposed based on a fringed micelle structure with lateral aggregation and enzyme susceptibility both limited by attached clusters of branch points. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of different pH conditions on the in vitro digestibility and physicochemical properties of citric acid-treated potato starch.

PubMed

Lee, Soo Yoon; Lee, Kwang Yeon; Lee, Hyeon Gyu

2018-02-01

The objective of this study was to investigate the influence of citric acid (CA) treatment (10, 20, and 30% of dry starch weight) under different pH conditions (3.5, 4.5, and 5.5) on the physicochemical properties, in vitro digestibility and prebiotic effects of potato starch. With the CA content increased, the degree of substitution of CA-starch treated at pH 3.5 and 4.5 wad significantly increased i.e. from 0.125 to 0.418 and from 0.078 to 0.167, respectively (p<0.05), except for starch treated at pH 5.5 (from 0.023 to 0.030). The resistant starch (RS) content of CA-starch was effectively increased compared to pH control made by changing pH from 3.5 to 5.5 with hydrochloric acid alone. The results of X-ray diffraction and swelling power were affected by pH condition, whereas they were less affected by the percentage of CA. Swelling power of treated starch also significantly decreased as the pH level decreased (p<0.05). Probiotic bacteria B. bifidum and L. acidophilus grown in medium with citrate starch showed substantial viability. These results suggest that pH conditions of CA modification substantially affect the degree of CA substitution, physicochemical properties, and nutritional value. Copyright © 2017 Elsevier B.V. All rights reserved.

Enamel and dentine demineralization by a combination of starch and sucrose in a biofilm - caries model.

PubMed

Botelho, Juliana Nunes; Villegas-Salinas, Mario; Troncoso-Gajardo, Pía; Giacaman, Rodrigo Andrés; Cury, Jaime Aparecido

2016-05-20

Sucrose is the most cariogenic dietary carbohydrate and starch is considered non-cariogenic for enamel and moderately cariogenic for dentine. However, the cariogenicity of the combination of starch and sucrose remains unclear. The aim of this study was to evaluate the effect of this combination on Streptococcus mutans biofilm composition and enamel and dentine demineralization. Biofilms of S. mutans UA159 were grown on saliva-coated enamel and dentine slabs in culture medium containing 10% saliva. They were exposed (8 times/day) to one of the following treatments: 0.9% NaCl (negative control), 1% starch, 10% sucrose, or 1% starch and 10% sucrose (starch + sucrose). To simulate the effect of human salivary amylase on the starch metabolization, the biofilms were pretreated with saliva before each treatment and saliva was also added to the culture medium. Acidogenicity of the biofilm was estimated by evaluating (2 times/day) the culture medium pH. After 4 (dentine) or 5 (enamel) days of growth, biofilms (n = 9) were individually collected, and the biomass, viable microorganism count, and polysaccharide content were quantified. Dentine and enamel demineralization was assessed by determining the percentage of surface hardness loss. Biofilms exposed to starch + sucrose were more acidogenic and caused higher demineralization (p < 0.0001) on either enamel or dentine than those exposed to each carbohydrate alone. The findings suggest that starch increases the cariogenic potential of sucrose.

In vitro Starch Hydrolysis Rate, Physico-chemical Properties and Sensory Evaluation of Butter Cake Prepared Using Resistant Starch Type III Substituted for Wheat Flour.

PubMed

Pongjanta, J; Utaipattanaceep, A; Naivikul, O; Piyachomkwan, K

2008-09-01

Resistant starch type III (RS III) derived from enzymatically debranched high amylose rice starch was prepared and used to make butter cake at different levels (0, 5, 10, 15 and 20%) in place of wheat flour. Physico-chemical properties, sensory evaluation, and in vitro starch hydrolysis rate of the developed butter cake were investigated. This study showed that the content of resistant starch in butter cake increased significantly (P<0.05) as the level of substitution with RS III increased from 2.1 to 4.4% of resistant starch content. The butter cake with RS III replacement had a significantly lower in vitro starch hydrolysis rate compared to the control cake (0% RS III). The rates of starch hydrolysis from 0 to 180 min digestion time for 0, 5, 10 15, and 20% RS III in place of wheat flour in butter cakes were 3.70 to 67.65%, 2.97 to 64.86%, 2.86 to 59.99%, 2.79 to 55.96 and 2.78 to 53.04% respectively. The physico-chemical properties of 5 to 10% RS III substituted with wheat flour in the butter cake were not significantly different from the control cake and were moderately accepted by panellists in the sensory evaluation test.

Mutations in durum wheat SBEII genes conferring increased amylose and resistant starch affect grain yield components, semolina and pasta quality and fermentation responses in rats

USDA-ARS?s Scientific Manuscript database

Increased amylose in wheat (Triticum spp.) starch is associated with increased resistant starch, a fermentable dietary fiber. Fermentation of resistant starch in the large intestine produces short-chain fatty acids that provide human health benefits. Since wheat foods are an important component of t...

A Forgotten Application of the Starch Test: C[subscript 4] Photosynthesis

ERIC Educational Resources Information Center

Harley, Suzanne M.

2013-01-01

In many labs on photosynthesis, the presence of starch in leaves is used as an indirect indicator of photosynthetic activity. Students do starch tests on leaves from plants that have been kept under a variety of conditions in order to check parameters for photosynthesis. The starch test can also be used to enable students to discover differences…

Ovary starch reserves and pistil development in avocado (Persea americana).

PubMed

Alcaraz, M Librada; Hormaza, J Ignacio; Rodrigo, Javier

2010-12-01

In avocado, only a very small fraction of the flowers are able to set fruit. Previous work in other woody perennial plant species has shown the importance of carbohydrates accumulated in the flower in the reproductive process. Thus, in order to explore the implications of the nutritive status of the flower in the reproductive process in avocado, the starch content in the pistil has been examined in individual pollinated and non-pollinated flowers at anthesis and during the days following anthesis. Starch content in different pistilar tissues in each flower was quantified with the help of an image analysis system attached to a microscope. Flowers at anthesis were rich in highly compartmentalized starch. Although no external morphological differences could be observed among flowers, the starch content varied widely at flower opening. Starch content in the ovary is largely independent of flower size because these differences were not correlated with ovary size. Differences in the progress of starch accumulation within the ovule integuments between pollinated and non-pollinated flowers occurred concomitantly with the triggering of the progamic phase. The results suggest that starch reserves in the ovary could play a significant role in the reproductive process in avocado. Copyright © Physiologia Plantarum 2010.

Amyloplast Membrane Protein SUBSTANDARD STARCH GRAIN6 Controls Starch Grain Size in Rice Endosperm1

PubMed Central

Matsushima, Ryo; Maekawa, Masahiko; Kusano, Miyako; Tomita, Katsura; Kondo, Hideki; Nishimura, Hideki; Crofts, Naoko; Fujita, Naoko; Sakamoto, Wataru

2016-01-01

Starch is a biologically and commercially important polymer of glucose. Starch is organized into starch grains (SGs) inside amyloplasts. The SG size differs depending on the plant species and is one of the most important factors for industrial applications of starch. There is limited information on genetic factors regulating SG sizes. In this study, we report the rice (Oryza sativa) mutant substandard starch grain6 (ssg6), which develops enlarged SGs in endosperm. Enlarged SGs are observed starting at 3 d after flowering. During endosperm development, a number of smaller SGs appear and coexist with enlarged SGs in the same cells. The ssg6 mutation also affects SG morphologies in pollen. The SSG6 gene was identified by map-based cloning and microarray analysis. SSG6 encodes a protein homologous to aminotransferase. SSG6 differs from other rice homologs in that it has a transmembrane domain. SSG6-green fluorescent protein is localized in the amyloplast membrane surrounding SGs in rice endosperm, pollen, and pericarp. The results of this study suggest that SSG6 is a novel protein that controls SG size. SSG6 will be a useful molecular tool for future starch breeding and applications. PMID:26792122

Fourier transform infrared and Raman spectroscopic study of the effect of the thermal treatment and extraction methods on the characteristics of ayocote bean starches.

PubMed

Bernardino-Nicanor, Aurea; Acosta-García, Gerardo; Güemes-Vera, Norma; Montañez-Soto, José Luis; de Los Ángeles Vivar-Vera, María; González-Cruz, Leopoldo

2017-03-01

Starches isolated from four ayocote bean varieties were modified by thermal treatment to determinate the effect of the treatment on the structural changes of ayocote bean starch. Scanning electron microscopy indicates that the starch granules have oval and round shapes, with heterogeneous sizes and fractures when the extraction method is used. The presence of new bands at 2850 and 1560 cm -1 in the FT-IR spectra showed that the thermal treatment of ayocote beans induced an interaction between the protein or lipid and the amylose or amylopectin, while the sharpest band at 3400 cm -1 indicated a dehydration process in the starch granule in addition to the presence of the band at 1260 cm -1 , indicating the product of the retrogradation process. The thermal treatment reduced the crystallinity as well as short-range order. Raman spectroscopy revealed that acute changes occurred in the polysaccharide bonds after thermal treatment. This study showed that the thermal treatment affected the structural properties of ayocote bean starches, the interactions of the lipids and proteins with starch molecules and the retrogradation process of starch.

Effects of alpha-amylase reaction mechanisms on analysis of resistant-starch contents.

PubMed

Moore, Samuel A; Ai, Yongfeng; Chang, Fengdan; Jane, Jay-lin

2015-01-22

This study aimed to understand differences in the resistant starch (RS) contents of native and modified starches obtained using two standard methods of RS content analysis: AOAC Method 991.43 and 2002.02. The largest differences were observed in native potato starch, cross-linked wheat distarch phosphate, and high-amylose corn starch stearic-acid complex (RS5) between using AOAC Method 991.43 with Bacillus licheniformis α-amylase (BL) and AOAC Method 2002.02 with porcine pancreatic α-amylase (PPA). To determine possible reasons for these differences, we hydrolyzed raw-starch granules with BL and PPA with equal activity at pH 6.9 and 37°C for up to 84 h and observed the starch granules displayed distinct morphological differences after the hydrolysis. Starches hydrolyzed by BL showed erosion on the surface of the granules; those hydrolyzed by PPA showed pitting on granule surfaces. These results suggested that enzyme reaction mechanisms, including the sizes of the binding sites and the reaction patterns of the two enzymes, contributed to the differences in the RS contents obtained using different methods of RS analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Improved TNT detoxification by starch addition in a nitrogen-fixing Methylophilus-dominant aerobic microbial consortium.

PubMed

Khan, Muhammad Imran; Lee, Jaejin; Yoo, Keunje; Kim, Seonghoon; Park, Joonhong

2015-12-30

In this study, a novel aerobic microbial consortium for the complete detoxification of 2,4,6-trinitrotoluene (TNT) was developed using starch as a slow-releasing carbon source under nitrogen-fixing conditions. Aerobic TNT biodegradation coupled with microbial growth was effectively stimulated by the co-addition of starch and TNT under nitrogen-fixing conditions. The addition of starch with TNT led to TNT mineralization via ring cleavage without accumulation of any toxic by-products, indicating improved TNT detoxification by the co-addition of starch and TNT. Pyrosequencing targeting the bacterial 16S rRNA gene suggested that Methylophilus and Pseudoxanthomonas population were significantly stimulated by the co-addition of starch and TNT and that the Methylophilus population became predominant in the consortium. Together with our previous study regarding starch-stimulated RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) degradation (Khan et al., J. Hazard. Mater. 287 (2015) 243-251), this work suggests that the co-addition of starch with a target explosive is an effective way to stimulate aerobic explosive degradation under nitrogen-fixing conditions for enhancing explosive detoxification. Copyright © 2015 Elsevier B.V. All rights reserved.