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Natural DNA variation at candidate loci is associated with potato chip color, tuber starch content, yield and starch yield  

PubMed Central

Complex characters of plants such as starch and sugar content of seeds, fruits, tubers and roots are controlled by multiple genetic and environmental factors. Understanding their molecular basis will facilitate diagnosis and combination of superior alleles in crop improvement programs (“precision breeding”). Association genetics based on candidate genes is one approach toward this goal. Tetraploid potato varieties and breeding clones related by descent were evaluated for 2  years for chip quality before and after cold storage, tuber starch content, yield and starch yield. Chip quality is inversely correlated with tuber sugar content. A total of 36 loci on 11 potato chromosomes were evaluated for natural DNA variation in 243 individuals. These loci included microsatellites and genes coding for enzymes that function in carbohydrate metabolism or transport (candidate loci). The markers were used to analyze population structure and were tested for association with the tuber quality traits. Highly significant and robust associations of markers with 1–4 traits were identified. Most frequent were associations with chip quality and tuber starch content. Alleles increasing tuber starch content improved chip quality and vice versa. With two exceptions, the most significant and robust associations (q < 0.01) were observed with DNA variants in genes encoding enzymes that function in starch and sugar metabolism or transport. Comparing linkage and linkage disequilibrium between loci provided evidence for the existence of large haplotype blocks in the breeding materials analyzed. Electronic supplementary material The online version of this article (doi:10.1007/s00122-008-0746-y) contains supplementary material, which is available to authorized users. PMID:18379755

Li, Li; Paulo, Maria-João; Strahwald, Josef; Lübeck, Jens; Hofferbert, Hans-Reinhard; Tacke, Eckhart; Junghans, Holger; Wunder, Jörg; Draffehn, Astrid; van Eeuwijk, Fred



Amylose Content in Tuber Starch of Wild Potato Species  

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Identification of the major starch synthase in the soluble fraction of potato tubers.  

PubMed Central

The major isoform of starch synthase from the soluble fraction of developing potato tubers has been purified and used to prepare an antibody and isolate a cDNA. The protein is 140 kD, and it is distinctly different in predicted primary amino acid sequence from other isoforms of the enzyme thus far described. Immunoinhibition and immunoblotting experiments and analysis of tubers in which activity of the isoform was reduced through expression of antisense mRNA revealed that the isoform accounts for approximately 80% of the activity in the soluble fraction of the tuber and that it is also bound to starch granules. Severe reductions in activity had no discernible effect on starch content or amylose-to-amylopectin ratio of starch in tubers. However, they caused a profound change in the morphology of starch granules, indicative of important underlying changes in the structure of starch polymers within the granule. PMID:8768372

Marshall, J; Sidebottom, C; Debet, M; Martin, C; Smith, A M; Edwards, A



Tuber starch amylose content is associated with cold-induced sweetening in potato  

PubMed Central

Cold-induced sweetening (CIS) is the accumulation of reducing sugars in potato tubers at low storage temperatures. It is undesirable because it results in dark fry products. Our study evaluated the relationship between genetic resistance to CIS and two starch parameters, amylose content and starch granule size. We found that the amylose content in four CIS-resistant varieties was higher than that in five susceptible varieties. Amylose content was influenced not only by variety but also storage, production year, and field location. However, interactions between amylose content and environmental variables were not detected. In contrast, starch granule size was not associated with CIS resistance. No effect of storage on starch granule size was detected, and interactions among variety, production year, and field location were observed. Tuber starch amylose content should be considered a source of variability for CIS. PMID:25493178

Jansky, Shelley H; Fajardo, Diego A



Properties of cast films made of chayote (Sechium edule Sw.) tuber starch reinforced with cellulose nanocrystals  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this study, cellulose (C) and cellulose nanocrystals (CN) were blended with chayote tuber (Sechium edule Sw.) starch (CS) in formulations cast into films. The films were conditioned at different storage temperatures and relative humidity (RH), and analyzed by mechanical tests, X-ray diffraction, ...


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

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

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.



Some Structural and Physicochemical Characteristics of Tuber and Root Starches  

Microsoft Academic Search

Starches from six different species (cassava, arrowroot, sweet potato, yam, canna and ginger) were isolated and some structural and physicochemical characteristics analysed and correlated. Phosphorous and amylose contents were determined using a colorimetric method and measuring iodine affinity, respectively. Molecular weight distributions of starches were analysed by Sepharose CL 2B. Granular shape and size distribution were performed using an image

F. H. G. Peroni; T. S. Rocha; C. M. L. Franco



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

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

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



Formation and deposition of amylose in the potato tuber starch granule are affected by the reduction of granule-bound starch synthase expression  

Microsoft Academic Search

The synthesls of amylose in amyloplasts is catalyzed by granule-bound starch synthase (GBSS). GBSS gene expression was inhibited via antisense RNA in Agrobacterium rhizogenes-transformed potato plants. Analysis of starch production and starch granule composition in transgenic tubers revealed that reduction of GBSS activlty always resulted in a reduc- tion of the production of amylose. Field experiments, performed over a 2-year

G. J. Kuipers; Evert Jacobsen; Richard G. F. Visser



Thermodynamic and structural properties of tuber starches from transgenic potato plants grown in vitro and in vivo.  


Potato plants harboring Phytochrome B (PHYB) gene from Arabidopsis thaliana or rol genes from Agrobacterium rhizogenes were used to study the effect of transgene expression on structure and properties of starch in tubers. Thermodynamic characteristics of starch (melting temperature, enthalpy of melting, thickness of crystalline lamellae) were shown to be variable depending on the transgene expression and plant culturing mode: in vitro or in soil. The expression of rolB or rolC genes in in vitro cultured plants evoked opposite effects on starch melting temperature and crystalline lamellae thickness. AtPHYB or rolB expression in the soil-grown potato led to the formation of more defective or more ordered starch structures, respectively, in comparison with starches of the same lines grown in vitro. On the whole, our study revealed genotype-dependent differences between starches extracted from tubers of in vitro or in vivo grown plants. PMID:25857977

Wasserman, Luybov A; Sergeev, Andrey I; Vasil'ev, Viktor G; Plashchina, Irina G; Aksenova, Nina P; Konstantinova, Tatyana N; Golyanovskaya, Svetlana A; Sergeeva, Lidiya I; Romanov, Georgy A



Enhancing sucrose synthase activity in transgenic potato (Solanum tuberosum L.) tubers results in increased levels of starch, ADPglucose and UDPglucose and total yield.  


Sucrose synthase (SuSy) is a highly regulated cytosolic enzyme that catalyzes the conversion of sucrose and a nucleoside diphosphate into the corresponding nucleoside diphosphate glucose and fructose. To determine the impact of SuSy activity in starch metabolism and yield in potato (Solanum tuberosum L.) tubers we measured sugar levels and enzyme activities in tubers of SuSy-overexpressing potato plants grown in greenhouse and open field conditions. We also transcriptionally characterized tubers of SuSy-overexpressing and -antisensed potato plants. SuSy-overexpressing tubers exhibited a substantial increase in starch, UDPglucose and ADPglucose content when compared with controls. Tuber dry weight, starch content per plant and total yield of SuSy-overexpressing tubers increased significantly over those of control plants. In contrast, activities of enzymes directly involved in starch metabolism in SuSy-overexpressing tubers were normal when compared with controls. Transcriptomic analyses using POCI arrays and the MapMan software revealed that changes in SuSy activity affect the expression of genes involved in multiple biological processes, but not that of genes directly involved in starch metabolism. These analyses also revealed a reverse correlation between the expressions of acid invertase and SuSy-encoding genes, indicating that the balance between SuSy- and acid invertase-mediated sucrolytic pathways is a major determinant of starch accumulation in potato tubers. Results presented in this work show that SuSy strongly determines the intracellular levels of UDPglucose, ADPglucose and starch, and total yield in potato tubers. We also show that enhancement of SuSy activity represents a useful strategy for increasing starch accumulation and yield in potato tubers. PMID:19608713

Baroja-Fernández, Edurne; Muñoz, Francisco José; Montero, Manuel; Etxeberria, Ed; Sesma, María Teresa; Ovecka, Miroslav; Bahaji, Abdellatif; Ezquer, Ignacio; Li, Jun; Prat, Salomé; Pozueta-Romero, Javier



Tuber starch amylose content is associated with cold-induced sweetening in potato  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cold induced sweetening (CIS) is the accumulation of reducing sugars in potato tubers due to cold storage. It is undesirable because it results in dark fry products. Potato varieties vary in resistance to CIS. Research efforts have focused on enzymes that contribute to the accumulation of reducing s...


Physicochemical and Functional Properties of Starch from Two Species of Curcuma  

Microsoft Academic Search

The properties of starch extracted from two species of Curcuma viz. Curcuma zedoaria and Curcuma malabarica were studied. The starch from C. malabarica tubers was white in color, while that from C. zedoaria was slightly yellowish due to the presence of the yellow pigment, curcumin. The granule size and shape, amylose content and solubility did not show noticeable difference between

A. N. Jyothi; S. N. Moorthy; B. Vimala



Effect of granule size on the interference colors of starch in polarized light.  


A Nikitin-Berek compensator tilted at 5.5 degrees in a polarizing microscope was used to create a background second-order blue interference color against which starch granules were examined. A grating monochromator showed the first interference minimum of the background was at 590 nm. Starch granules have a radial molecular structure. Thus, some radii were in line with the axis of the compensator while others were across the compensator axis. Where radial birefringence counteracted the background birefringence, starch granules had two quadrants with a bright yellow first-order interference color. Where radial birefringence added to the background birefringence, there were two quadrants of second-order blue (higher than the background). In yellow quadrants where birefringence was reduced, the wavelength of the first interference minimum was reduced. In blue quadrants where birefringence was increased, the wavelength of the first interference minimum was increased. The extent to which the interference minimum of the background birefringence was shifted by starch granules was strongly dependent on the size of the starch granules. For yellow quadrants, the shifts were: r = -0.87, P < 0.001, n = 22 for corn starch; r = - 0.94, P <0.001, n = 22 for tapioca starch; and r = -0.94, P <0.001, n = 12 for potato starch. For blue quadrants, the shifts were: r = 0.80, P < 0.001, n = 22 for corn; r = 0.81, P < 0.001, n = 22 for tapioca; and r = 0.93, P < 0.001, n = 16 for potato. When interference colors are used to evaluate starch granules, the granules should be similar in size or a correction must be made for granule size, and the Michel-Lévy chart of interference colors may be used to collect data subjectively. PMID:19585308

Swatland, H J



Extensive Variation in Fried Chip Color and Tuber Composition in Cold-Stored Tubers of Wild Potato (Solanum) Germplasm  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cold-induced sweetening and browning in the Maillard reaction have driven extensive research in the areas of plant physiology, biochemistry, and food science in Solanum tuberosum. To date, research in these areas excluded wild relatives of potato. This is the first assessment of cold-stored tuber c...


Ethylene in the atmosphere of commercial potato (Solanum tuberosum) storage bins and potential effects on tuber respiration rate and fried chip color  

Technology Transfer Automated Retrieval System (TEKTRAN)

Careful storage management is required to maintain post-harvest potato tuber quality. The plant growth regulator ethylene has well documented effects on potato tuber respiration rate, fried product color, and sprouting, but data on the amount of ethylene present in ventilated potato storages and how...


Root and tuber phytoliths and starch grains document manioc ( Manihot esculenta ) arrowroot ( Maranta arundinacea ) and llerén ( Calathea sp. ) at the real alto site Ecuador  

Microsoft Academic Search

Although roots and tubers are dietary staples in many parts of the world, their use is difficult to document archaeo logically\\u000a because their organic remains are often poorly preserved in archaeological sedi ments. Here we describe the first diagnostic\\u000a phytoliths from the underground storage organs of the important New World agricultural crops manioc or yuca(Manihot esculenta Crantz), arrowroot(Maranta arundinacea L.),

Karol Chandler Ezell; Deborah M. Pearsall; James A. Zeidler



Tuberous Sclerosis  


... may have learning problems or seizures that are hard to control. Tuberous sclerosis affects every 1 in 6,000 people in the United States. The disorder occurs in both sexes and in people of all races and ethnic ...


Tubers and rhizome fragments as propagules: competence for vegetative reproduction in Equisetum arvense  

Microsoft Academic Search

Rhizome fragments (referred to as “fragments”) and tubers of Equisetum arvense L. were cultured in order to investigate their competence with respect to vegetative reproduction. The starch concentration of the fragments was lower than that of the tubers, but the initial growth of new individuals from these fragments was superior to that from tubers obtained from the same dry mass.

Yoshiaki Sakamaki; Yoshio Ino



Immunocytochemical localization of ADPglucose pyrophosphorylase in developing potato tuber cells  

SciTech Connect

The subcellular localization of ADPglucose pyrophosphorylase, a key regulatory enzyme in starch biosynthesis, was determined in developing potato tuber cells by immunocytochemical localization techniques at the light microscopy level. Specific labeling of ADPglucose pyrophosphorylase by either immunofluorescence or immunogold followed by silver enhancement was detected only in the amyloplasts and indicates that this enzyme is located exclusively in the amyloplasts in developing potato tuber cells. Labeling occurred on the starch grains and, in some instances, specific labeling patterns were evident which may be related to sites active in starch deposition.

Kim, Woo Taek; Franceschi, V.R.; Okita, T.W. (Washington State Univ., Pullman (USA)); Robinson, N.L.; Morell, M.; Preiss, J. (Michigan State Univ., East Lansing (USA))



Starch Metabolism in Arabidopsis  

PubMed Central

Starch is the major non-structural carbohydrate in plants. It serves as an important store of carbon that fuels plant metabolism and growth when they are unable to photosynthesise. This storage can be in leaves and other green tissues, where it is degraded during the night, or in heterotrophic tissues such as roots, seeds and tubers, where it is stored over longer time periods. Arabidopsis accumulates starch in many of its tissues, but mostly in its leaves during the day. It has proven to be a powerful genetic system for discovering how starch is synthesised and degraded, and new proteins and processes have been discovered. Such work has major significance for our starch crops, whose yield and quality could be improved by the application of this knowledge. Research into Arabidopsis starch metabolism has begun to reveal how its daily turnover is integrated into the rest of metabolism and adapted to the environmental conditions. Furthermore, Arabidopsis mutant lines deficient in starch metabolism have been employed as tools to study other biological processes ranging from sugar sensing to gravitropism and flowering time control. This review gives a detailed account of the use of Arabidopsis to study starch metabolism. It describes the major discoveries made and presents an overview of our understanding today, together with some as-yet unresolved questions. PMID:23393426

Streb, Sebastian; Zeeman, Samuel C.



Effect of infection by Rhizopus oryzae on biochemical composition of stored potato tubers.  


The carbohydrate fractions, protein and lipid contents of two cultivars of potato namely, Irish Cobbler and Red Pontiac, were altered quantitatively by Rhizopus oryzae during the 10-day incubation period. Glucose content increased during the incubation period for both healthy and inoculated tubers. Starch, maltose, sucrose, protein and lipid contents decreased more rapidly in inoculated tubers than in healthy tubers in both cultivars. The depletion in starch and protein in the infected tubers appeared to be greater for Irish Cobbler than in Red Pontiac; decreases for other constituents seemed fairly comparable. PMID:10472791

Amadioha, A C



Encapsulation altered starch digestion: toward developing starch-based delivery systems.  


Starch is an abundant biomaterial that forms a vital energy source for humans. Altering its digestion, e.g. increasing the proportions of slowly digestible starch (SDS) and resistant starch (RS), would revolutionize starch utility in addressing a number of health issues related to glucose absorption, glycemic index and colon health. The research reported in this article is based on my hypothesis that water channels present in the B-type starch crystalline matrix, particularly in tuber starches, can embed guest molecules such as nutraceuticals, drugs, flavor compounds and vitamins leading to altered starch digestion. Toward this goal, potato starch has been chosen as the model tuber starch, and ibuprofen, benzocaine, sulfapyridine, curcumin, thymol and ascorbic acid as model guest molecules. X-ray powder diffraction and FT-IR analyses clearly suggest the incorporation of guest molecules in the water channels of potato starch. Furthermore, the in vitro digestion profiles of complexes are intriguing with major variations occurring after 60 min of starch digestion and finally at 120 min. These changes are concomitantly reflected in the SDS and RS amounts, with about 24% decrease in SDS for benzocaine complex and 6% increase in RS for ibuprofen complex, attesting the ability of guest molecule encapsulation in modulating the digestion properties of potato starch. Overall, this research provides an elegant opportunity for the design and development of novel starch-based stable carriers that not only bestow tailored glucose release rates but could also transport health promoting and disease preventing compounds. PMID:24299816

Janaswamy, Srinivas



Structural and molecular basis of starch viscosity in hexaploid wheat.  


Wheat starch is considered to have a low paste viscosity relative to other starches. Consequently, wheat starch is not preferred for many applications as compared to other high paste viscosity starches. Increasing the viscosity of wheat starch is expected to increase the functionality of a range of wheat flour-based products in which the texture is an important aspect of consumer acceptance (e.g., pasta, and instant and yellow alkaline noodles). To understand the molecular basis of starch viscosity, we have undertaken a comprehensive structural and rheological analysis of starches from a genetically diverse set of wheat genotypes, which revealed significant variation in starch traits including starch granule protein content, starch-associated lipid content and composition, phosphate content, and the structures of the amylose and amylopectin fractions. Statistical analysis highlighted the association between amylopectin chains of 18-25 glucose residues and starch pasting properties. Principal component analysis also identified an association between monoesterified phosphate and starch pasting properties in wheat despite the low starch-phosphate level in wheat as compared to tuber starches. We also found a strong negative correlation between the phosphate ester content and the starch content in flour. Previously observed associations between internal starch granule fatty acids and the swelling peak time and pasting temperature have been confirmed. This study has highlighted a range of parameters associated with increased starch viscosity that could be used in prebreeding/breeding programs to modify wheat starch pasting properties. PMID:18459791

Ral, J-P; Cavanagh, C R; Larroque, O; Regina, A; Morell, M K



Identification of epileptogenic tubers in patients with tuberous sclerosis complex  

Microsoft Academic Search

Identification of epileptogenic tubers in patients with tuberous sclerosis complex Tuberous sclerosis complex (TSC) is associated with epilepsy and mental retardation. The principal aim of this thesis was to identify epileptogenic tuber(s) enabling the selection of patients for epilepsy surgery. In addition we analysed possible determinants of cognitive functioning in patients with TSC. Genotype (different TSC1 and TSC2 mutations, tuber

F. E. Jansen



Tubers and rhizome fragments as propagules: competence for vegetative reproduction in Equisetum arvense.  


Rhizome fragments (referred to as "fragments") and tubers of Equisetum arvense L. were cultured in order to investigate their competence with respect to vegetative reproduction. The starch concentration of the fragments was lower than that of the tubers, but the initial growth of new individuals from these fragments was superior to that from tubers obtained from the same dry mass. This superior growth was due to the large number of buds (grown from nodes) and aerial shoots on the fragments. The competence for vegetative reproduction depended on the relationship between the stored starch and the number of buds. PMID:16937024

Sakamaki, Yoshiaki; Ino, Yoshio



Physical and functional properties of arrowroot starch extrudates.  


Arrowroot starch, a commercially underexploited tuber starch but having potential digestive and medicinal properties, has been subjected to extrusion cooking using a single screw food extruder. Different levels of feed moisture (12%, 14%, and 16%) and extrusion temperatures (140, 150, 160, 170, 180, and 190 degrees C) were used for extrusion. The physical properties--bulk density, true density, porosity, and expansion ratio; functional properties such as water absorption index, water solubility index, oil absorption index, pasting, rheological, and textural properties; and in vitro enzyme digestibility of the extrudates were determined. The expansion ratio of the extrudates ranged from 3.22 to 6.09. The water absorption index (6.52 to 8.85 g gel/g dry sample), water solubility index (15.92% to 41.31%), and oil absorption index (0.50 to 1.70 g/g) were higher for the extrudates in comparison to native starch (1.81 g gel/g dry sample, 1.16% and 0.60 g/g, respectively). The rheological properties, storage modulus, and loss modulus of the gelatinized powdered extrudates were significantly lower (P < 0.05) and these behaved like solutions rather than a paste or a gel. Hardness and toughness were more for the samples extruded at higher feed moisture and lower extrusion temperature, whereas snap force and energy were higher at lower feed moisture and temperature. There was a significant decrease in the percentage digestibility of arrowroot starch (30.07% after 30 min of incubation with the enzyme) after extrusion (25.27% to 30.56%). Extrusion cooking of arrowroot starch resulted in products with very good expansion, color, and lower digestibility, which can be exploited for its potential use as a snack food. PMID:19323747

Jyothi, A N; Sheriff, J T; Sajeev, M S



Investigating Starch  

NSDL National Science Digital Library

In this activity (on pages 10-15), learners investigate starch in human diets and how plants make starch (carbohydrates) to use as their food source. Testing with a dropper of iodine in Part One, learners discover that starch content differs from food to food. In Part Two, learners taste chewed and unchewed food and compare the starch content.




NSDL National Science Digital Library

Using this project will expose you to concepts of color, color wheels, color combinations, and techniques of using color. Use the following links, follow the directions to define color terms, create color schemes and explore the use of color in creating designs. Color Scheme Generator 2 This site identifiesbasic terms related to color, using acolor wheeland making color schemes. Color Theory This site explains terminology of color. Color Theory Tutorial This site gives excellent examples and information about ...

Mrs. Dent




NSDL National Science Digital Library

This project will be used to teach the importance of color. Watch the following video about color Primary Colors Click on the link Exploration of Color. When you get into the website select the different colors to see what secondary colors are made from the primary colors. Review the following siteColor Theory and then design and paint a color wheel. ...




Cytological examination of pink eye afflicted tubers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pink eye is a tuber disorder of undetermined cause that can result in serious processing complications and storage losses throughout North America. Pink eye symptoms progress from ephemeral light pink colorations around bud-end eyes to water-soaked or dried and cracked “corky-patch” periderm. Late s...


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


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. PMID:24054264

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



The molecular deposition of transgenically modified starch in the starch granule as imaged by functional microscopy.  


The molecular deposition of starch extracted from normal plants and transgenically modified potato lines was investigated using a combination of light microscopy, environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CLSM). ESEM permitted the detailed (10 nm) topographical analysis of starch granules in their hydrated state. CLSM could reveal internal molar deposition patterns of starch molecules. This was achieved by equimolar labelling of each starch molecule using the aminofluorophore 8-amino-1,3,6-pyrenetrisulfonic acid (APTS). Starch extracted from tubers with low amylose contents (suppressed granule bound starch synthase, GBSS) showed very little APTS fluorescence and starch granules with low molecular weight amylopectin and/or high amylose contents showed high fluorescence. Growth ring structures were sharper in granules with normal or high amylose contents. High amylose granules showed a relatively even distribution in fluorescence while normal and low amylose granules had an intense fluorescence in the hilum indicating a high concentration of amylose in the centre of the granule. Antisense of the starch phosphorylating enzyme (GWD) resulted in low molecular weight amylopectin and small fissures in the granules. Starch granules with suppressed starch branching enzyme (SBE) had severe cracks and rough surfaces. Relationships between starch molecular structure, nano-scale crystalline arrangements and topographical-morphological features were estimated and discussed. PMID:14572478

Blennow, Andreas; Hansen, Michael; Schulz, Alexander; Jørgensen, Kirsten; Donald, Athene M; Sanderson, James



Potato tuber dormancy  

Technology Transfer Automated Retrieval System (TEKTRAN)

The date that potato tubers begin to sprout must be carefully managed to maximize crop value. Spouting of fresh, chip and fry processing tubers during storage can decrease crop value, increase water loss and pressure bruising, and may promote pathogen entry. A lack of uniform sprouting in seed potat...


Phenotypic and genotypic characterization of an amylose-free starch mutant of the potato  

Microsoft Academic Search

The amylose-free (amf) potato mutant 86.040 has been characterized phenotypically and genotypically. Not only storage starch in tubers and metabolic starch in leaves but also starch in cells with specific functions, such as columella cells in the root cap and guard cells of stomata, was amylose-free. Doubled amf-clones of 86.040 flowered well, but the percentage of stainable pollen was low

E. Jacobsen; J. H. M. Hovenkamp-Hermelink; H. T. Krijgsheld; H. Nijdam; L. P. Pijnacker; B. Witholt; W. J. Feenstra



Starch Slime  

NSDL National Science Digital Library

Learners mix liquid water with solid cornstarch. They investigate the slime produced, which has properties of both a solid and a liquid. When they press hard on the starch slime with their fingers, the slime acts like a solid. Starch in water is a suspension of solid particles in water. When learners leave the starch slime alone, it flows like a liquid. A great opportunity to discuss states of matter. This activity is currently used in the Nature of Matter Unit in OMSI's Chemistry Lab. Cost estimates are per 100 learners.

Oregon Museum of Science and Industry



Stem end chip defect in tubers used for potato chip production  

Technology Transfer Automated Retrieval System (TEKTRAN)

Stem-end chip defect (SECD) is a serious tuber quality concern that affects chipping potatoes (Solanum tuberosum). SECD defect is characterized by dark-colored vascular tissues and adjacent cortical tissues at the tuber stem-end portion of potato chips after frying. Chips with SECD are unattractive ...


Changing Colors  

NSDL National Science Digital Library

In this challenge, learners have to figure out in what order to combine five solutions to change the color from clear, to yellow, to blue, and back to clear. The five chemicals are potassium iodide, sodium thiosulfate, sodium hypochlorite (Clorox bleach), soluble starch (Niagara spray starch), and water. The color changes indicate chemical reactions, and the lesson includes some background information about the reactions that create different colors. Suggestions are given for guiding learners through systematic approaches to making the different combinations and observing the results, and for explaining to different age groups what happens when the solutions are combined.




The Sucrose Transporter StSUT1 Localizes to Sieve Elements in Potato Tuber Phloem and Influences Tuber Physiology and Development1[w  

PubMed Central

The sucrose (Suc) H+-cotransporter StSUT1 from potato (Solanum tuberosum), which is essential for long-distance transport of Suc and assumed to play a role in phloem loading in mature leaves, was found to be expressed in sink tubers. To answer the question of whether SUT1 serves a function in phloem unloading in tubers, the promoter was fused to gusA and expression was analyzed in transgenic potato. SUT1 expression was unexpectedly detected not in tuber parenchyma but in the phloem of sink tubers. Immunolocalization demonstrated that StSUT1 protein was present only in sieve elements of sink tubers, cells normally involved in export of Suc from the phloem to supply developing tubers, raising the question of the role of SUT1 in tubers. SUT1 expression was inhibited by antisense in transgenic potato plants using a class I patatin promoter B33, which is primarily expressed in the phloem of developing tubers. Reduced SUT1 expression in tubers did not affect aboveground organs but led to reduced fresh weight accumulation during early stages of tuber development, indicating that in this phase SUT1 plays an important role for sugar transport. Changes in Suc- and starch-modifying enzyme activities and metabolite profiles are consistent with the developmental switch in unloading mechanisms. Altogether, the findings may suggest a role of SUT1 in retrieval of Suc from the apoplasm, thereby regulating the osmotic potential in the extracellular space, or a direct role in phloem unloading acting as a phloem exporter transferring Suc from the sieve elements into the apoplasm. PMID:12529519

Kühn, Christina; Hajirezaei, Mohammad-Reza; Fernie, Alisdair R.; Roessner-Tunali, Ute; Czechowski, Tomasz; Hirner, Brigitte; Frommer, Wolf B.



Changes in main nutrients and medicinal composition of Chinese yam (Dioscorea opposita) tubers during storage.  


The changes in the main nutrient and medicinal components during the storage of the Chinese yam (Dioscorea opposita) tubers were studied. The harvested tubers were stored under ambient conditions (10 °C to 18 °C, 60 % to 80 % Relative Humidity) and cold temperature and packaged conditions (4 °C, 60 % to 65 % Relative Humidity) for 45 day. The allantoin, starch, total alcohol-soluble sugar, reducing sugar, protein, and moisture contents of the samples were evaluated. Their amylase activities were also investigated. Results of ambient conditions indicated that, during storage, moisture decreased by 67.96 % to 56.51 %, and total sugars, reducing sugars, and protein increased by 6.49 % to 9.81 %, 1.7 % to 2.27 %, and 13.02 % to 14.55 %, respectively. Starch and enzyme activities increased during the early days of storage and progressively decreased, and the content of allantoin changed in volatility. The changes were more significant at cold temperatures and packaged conditions than at ambient conditions. This result suggests that after-ripening occurred in the early stages of Chinese yam tubers, which positively affected the nutritional potential of the tubers by a marked increase in nutrients. Low-temperature sweetening greatly affects the nutritional potential of tubers by a series of complicated interactions between starch and sugars at 4 °C. PMID:25328193

Zhang, Zhidan; Gao, Wenyuan; Wang, Renfang; Huang, Luqi



Starch: Structure, Properties, Chemistry, and Enzymology  

NASA Astrophysics Data System (ADS)

Starch is a very important and widely distributed natural product, occurring in the leaves of green plants, seeds, fruits, stems, roots, and tubers. It serves as the chemical storage form of the energy of the sun and is the primary source of energy for the organisms on the Earth. Starch is composed of two kinds of polysaccharides, amylose and amylopectin, exclusively composed of D-glucose residues with ?-(1?4) linkages in a linear amylose and ?-(1?4) linkages and ˜5% ?-(1?6) branch linkages in amylopectin, both combined in a water-insoluble granule that is partially crystalline and whose size, shape, and morphology are dependent on its biological source. The properties, isolation, fractionation, enzymatic degradation, biosynthesis, chemical modification, and specific methods of analysis of starch are presented.

Robyt, John F.



NSDL National Science Digital Library

In this project, students will learn about primary, secondary, and complementary colors. After exploring a few sites and participating in a few deep questions as a class, they will create an optical illusion using complimentary colors. Younger students who are learning this unit will need to do this activity with a parent or as a class with a teacher or aide. INTRODUCTION: Questions to discuss with the students: 1. What colors do you see in this room? 2. What are some jobs that use colors? An Artist? Decorator? ...




Starch biosynthetic genes and enzymes are expressed and active in the absence of starch accumulation in sugar beet tap-root  

PubMed Central

Background Starch is the predominant storage compound in underground plant tissues like roots and tubers. An exception is sugar beet tap-root (Beta vulgaris ssp altissima) which exclusively stores sucrose. The underlying mechanism behind this divergent storage accumulation in sugar beet is currently not fully known. From the general presence of starch in roots and tubers it could be speculated that the lack in sugar beet tap-roots would originate from deficiency in pathways leading to starch. Therefore with emphasis on starch accumulation, we studied tap-roots of sugar beet using parsnip (Pastinaca sativa) as a comparator. Results Metabolic and structural analyses of sugar beet tap-root confirmed sucrose as the exclusive storage component. No starch granules could be detected in tap-roots of sugar beet or the wild ancestor sea beet (Beta vulgaris ssp. maritima). Analyses of parsnip showed that the main storage component was starch but tap-root tissue was also found to contain significant levels of sugars. Surprisingly, activities of four main starch biosynthetic enzymes, phosphoglucomutase, ADP-glucose pyrophosphorylase, starch synthase and starch branching enzyme, were similar in sugar beet and parsnip tap-roots. Transcriptional analysis confirmed expression of corresponding genes. Additionally, expression of genes involved in starch accumulation such as for plastidial hexose transportation and starch tuning functions could be determined in tap-roots of both plant species. Conclusion Considering underground storage organs, sugar beet tap-root upholds a unique property in exclusively storing sucrose. Lack of starch also in the ancestor sea beet indicates an evolved trait of biological importance. Our findings in this study show that gene expression and enzymatic activity of main starch biosynthetic functions are present in sugar beet tap-root during storage accumulation. In view of this, the complete lack of starch in sugar beet tap-roots is enigmatic. PMID:24758347



Comparative Studies on Some Physicochemical, Thermal, Morphological, and Pasting Properties of Acid-thinned Jicama and Maize Starches  

Microsoft Academic Search

Comparative studies on acid hydrolysis of jicama and maize starch were carried out using concentrations of hydrochloric acid\\u000a of 1.5%, 3.0%, and 4.5% (w\\/v), for 3 and 6 h, at 40°C. Native maize and jicama starches showed important morphological, thermal, and structural differences\\u000a from those of tubers and cereals which potentially offer diverse industrial applications. Jicama starch showed low amylose\\u000a content

Silvia Lorena Amaya-Llano; Fernando Martínez-Bustos; Ana Laura Martínez Alegría; José de Jesús Zazueta-Morales



Two alternative methods to predict amylose content in rice grain by using tristimulus CIELAB values and developing a specific color board of starch-iodine complex solution  

Technology Transfer Automated Retrieval System (TEKTRAN)

Amylose content was predicted by measuring tridimensional L*a*b* values in starch-iodine solutions and building a regression model. The developed regression model showed a highly significant relationship (R2= 0.99) between the L*a*b values and the amylose content. Apparent amylose content was strong...


Tuber Storage Proteins  

PubMed Central

A wide range of plants are grown for their edible tubers, but five species together account for almost 90 % of the total world production. These are potato (Solanum tuberosum), cassava (Manihot esculenta), sweet potato (Ipomoea batatus), yams (Dioscorea spp.) and taro (Colocasia, Cyrtosperma and Xanthosoma spp.). All of these, except cassava, contain groups of storage proteins, but these differ in the biological properties and evolutionary relationships. Thus, patatin from potato exhibits activity as an acylhydrolase and esterase, sporamin from sweet potato is an inhibitor of trypsin, and dioscorin from yam is a carbonic anhydrase. Both sporamin and dioscorin also exhibit antioxidant and radical scavenging activity. Taro differs from the other three crops in that it contains two major types of storage protein: a trypsin inhibitor related to sporamin and a mannose?binding lectin. These characteristics indicate that tuber storage proteins have evolved independently in different species, which contrasts with the highly conserved families of storage proteins present in seeds. Furthermore, all exhibit biological activities which could contribute to resistance to pests, pathogens or abiotic stresses, indicating that they may have dual roles in the tubers. PMID:12730067




Novel candidate genes influencing natural variation in potato tuber cold sweetening identified by comparative proteomics and association mapping  

PubMed Central

Background Higher plants evolved various strategies to adapt to chilling conditions. Among other transcriptional and metabolic responses to cold temperatures plants accumulate a range of solutes including sugars. The accumulation of the reducing sugars glucose and fructose in mature potato tubers during exposure to cold temperatures is referred to as cold induced sweetening (CIS). The molecular basis of CIS in potato tubers is of interest not only in basic research on plant adaptation to environmental stress but also in applied research, since high amounts of reducing sugars affect negatively the quality of processed food products such as potato chips. CIS-tolerance varies considerably among potato cultivars. Our objective was to identify by an unbiased approach genes and cellular processes influencing natural variation of tuber sugar content before and during cold storage in potato cultivars used in breeding programs. We compared by two-dimensional polyacrylamide gel electrophoresis the tuber proteomes of cultivars highly diverse for CIS. DNA polymorphisms in genomic sequences encoding differentially expressed proteins were tested for association with tuber starch content, starch yield and processing quality. Results Pronounced natural variation of CIS was detected in tubers of a population of 40 tetraploid potato cultivars. Significant differences in protein expression were detected between CIS-tolerant and CIS-sensitive cultivars before the onset as well as during cold storage. Identifiable differential proteins corresponded to protease inhibitors, patatins, heat shock proteins, lipoxygenase, phospholipase A1 and leucine aminopeptidase (Lap). Association mapping based on single nucleotide polymorphisms supported a role of Lap in the natural variation of the quantitative traits tuber starch and sugar content. Conclusions The combination of comparative proteomics and association genetics led to the discovery of novel candidate genes for influencing the natural variation of quantitative traits in potato tubers. One such gene was a leucine aminopeptidase not considered so far to play a role in starch sugar interconversion. Novel SNP’s diagnostic for increased tuber starch content, starch yield and chip quality were identified, which are useful for selecting improved potato processing cultivars. PMID:23919263



Concerted suppression of all starch branching enzyme genes in barley produces amylose-only starch granules  

PubMed Central

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



Quantitative Assay for Starch by Colorimetry Using a Desktop Scanner  

ERIC Educational Resources Information Center

The procedure to produce standard curve for starch concentration measurement by image analysis using a color scanner and computer for data acquisition and color analysis is described. Color analysis is performed by a Visual Basic program that measures red, green, and blue (RGB) color intensities for pixels within the scanner image.

Matthews, Kurt R.; Landmark, James D.; Stickle, Douglas F.



The potato amylase inhibitor gene SbAI regulates cold-induced sweetening in potato tubers by modulating amylase activity.  


Potato cold-induced sweetening (CIS) is critical for the postharvest quality of potato tubers. Starch degradation is considered to be one of the key pathways in the CIS process. However, the functions of the genes that encode enzymes related to starch degradation in CIS and the activity regulation of these enzymes have received less attention. A potato amylase inhibitor gene known as SbAI was cloned from the wild potato species Solanum berthaultii. This genetic transformation confirmed that in contrast to the SbAI suppression in CIS-resistant potatoes, overexpressing SbAI in CIS-sensitive potatoes resulted in less amylase activity and a lower rate of starch degradation accompanied by a lower reducing sugar (RS) content in cold-stored tubers. This finding suggested that the SbAI gene may play crucial roles in potato CIS by modulating the amylase activity. Further investigations indicated that pairwise protein-protein interactions occurred between SbAI and ?-amylase StAmy23, ?-amylases StBAM1 and StBAM9. SbAI could inhibit the activities of both ?-amylase and ?-amylase in potato tubers primarily by repressing StAmy23 and StBAM1, respectively. These findings provide the first evidence that SbAI is a key regulator of the amylases that confer starch degradation and RS accumulation in cold-stored potato tubers. PMID:24985879

Zhang, Huiling; Liu, Jun; Hou, Juan; Yao, Ying; Lin, Yuan; Ou, Yongbin; Song, Botao; Xie, Conghua



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


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 ?m conformed by several starch granules of wedge shape that range from 2 to 7 ?m. 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. PMID:24463263

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



Heterologous expression of AtPAP2 in transgenic potato influences carbon metabolism and tuber development.  


Changes in carbon flow and sink/source activities can affect floral, architectural, and reproductive traits of plants. In potato, overexpression (OE) of the purple acid phosphatase 2 of Arabidopsis (AtPAP2) resulted in earlier flowering, faster growth rate, increased tubers and tuber starch content, and higher photosynthesis rate. There was a significant change in sucrose, glucose and fructose levels in leaves, phloem and sink biomass of the OE lines, consistent with an increased expression of sucrose transporter 1 (StSUT1). Furthermore, the expression levels and enzyme activity of sucrose-phosphate synthase (SPS) were also significantly increased in the OE lines. These findings strongly suggest that higher carbon supply from the source and improved sink strength can improve potato tuber yield. PMID:25173632

Zhang, Youjun; Sun, Feng; Fettke, Joerg; Schöttler, Mark Aurel; Ramsden, Lawrence; Fernie, Alisdair R; Lim, Boon Leong



[Pulmonary involvement in tuberous sclerosis].  


The authors present a case of tuberous sclerosis with marked pulmonary involvement, confirmed by both radiological and pathological studies. The radiological manifestations and basic pathology of this rare condition are reviewed with emphasis on differential diagnosis. PMID:3045877

Kullnig, P; Flückiger, F; Kopp, W; Popper, H




Technology Transfer Automated Retrieval System (TEKTRAN)

High intensity ultrasound (sonication) was investigated as a method to rapidly purify starch from sorghum and other cereal grains. To improve the process, buffers were optimized to solubilize sorghum proteins in combination with the sonication. Protein content and starch color were determined to e...


Starch grains reveal early root crop horticulture in the Panamanian tropical forest  

Microsoft Academic Search

Native American populations are known to have cultivated a large number of plants and domesticated them for their starch-rich underground organs. Suggestions that the likely source of many of these crops, the tropical forest, was an early and influential centre of plant husbandry have long been controversial because the organic remains of roots and tubers are poorly preserved in archaeological

Dolores R. Piperno; Anthony J. Ranere; Irene Holst; Patricia Hansell



Suitability of Edible Bean and Potato Starches for Starch Noodles  

Microsoft Academic Search

Cereal Chem. 73(3):302-308 Starch noodles were prepared from two types of bean (navy and cial starch noodles with respect to cooking loss and cooked weight. Tex- pinto) starch and three sources of potato starch (ND651-9, Mainechip, ture profile analysis (TPA) results showed starch noodles made from and commercial potato starch). Physicochemical properties of those bean starches had higher hardness values,




Colors, Colors?  

NSDL National Science Digital Library

In this activity related to the famous "Stroop Effect," learners explore how words influence what we see and how the brain handles "mixed messages." Learners read colored words and are asked to say the color of the word, not what the word says. Learners use a data table to keep track of where they have trouble reading the colors. They analyze this data by answering questions and drawing conclusions. Learners can also take this test using the online version.

Susan Songstad



Synthesis of Rosin Acid Starch Catalyzed by Lipase  

PubMed Central

Rosin, an abundant raw material from pine trees, was used as a starting material directly for the synthesis of rosin acid starch. The esterification reaction was catalyzed by lipase (Novozym 435) under mild conditions. Based on single factor experimentation, the optimal esterification conditions were obtained as follows: rosin acid/anhydrous glucose unit in the molar ratio 2?:?1, reaction time 4?h at 45°C, and 15% of lipase dosage. The degree of substitution (DS) reaches 0.098. Product from esterification of cassava starch with rosin acid was confirmed by FTIR spectroscopy and iodine coloration analysis. Scanning electron microscopy and X-ray diffraction analysis showed that the morphology and crystallinity of the cassava starch were largely destroyed. Thermogravimetric analysis indicated that thermal stability of rosin acid starch decreased compared with native starch. PMID:24977156

Lin, Rihui; Li, He; Long, Han; Su, Jiating; Huang, Wenqin



Covalent Structures of Potato Tuber Lipases (Patatins) and Implications for Vacuolar Import*S?  

PubMed Central

Proteome data of potato (Solanum tuberosum) tuber juice and of purified potato tuber vacuoles indicated that mature patatins may perhaps lack a C-terminal propeptide. We have confirmed this by complete mass spectrometric sequencing of a number of patatin variants as well as their N-linked complex-type glycans from the starch-rich cultivar Kuras. For this cultivar full-length patatin cDNAs have also been sequenced, as the patatin locus is highly polymorphous. It is well known that patatins are located in the vacuoles of potato tubers. Furthermore, the complex glycan structures show that the path is via the Golgi apparatus. However, the vacuolar targeting signal has never been identified for this storage and defense protein, which amounts to 25–40% of tuber protein. We propose that a six-residue C-terminal propeptide, -ANKASY-COO– comprises this signal. The crystallographic structure of a recombinant patatin (Rydel, T. J., Williams, J. M., Krieger, E., Moshiri, F., Stallings, W. C., Brown, S. M., Pershing, J. C., Prucell, J. P., and Alibhai, M. F. (2003) Biochemistry 42, 6696–6708), which included this propeptide thus, for the first time, shows the structure of a putative ligand of the vacuolar sorting receptor and processing enzyme responsible for patatin import. PMID:19211558

Welinder, Karen G.; Jørgensen, Malene



In vitro digestibility and some physicochemical properties of starch from wild and cultivated amadumbe corms.  


Amadumbe, commonly known as taro, is an indigenous underutilised tuber to Southern Africa. In this study, starch functional properties and in vitro starch digestibility of processed products from wild and cultivated amadumbe were determined. Starch extracts from both amadumbe types had similar contents of total starch (approx. 95%). Wild and cultivated amadumbe starch granules were polygonal and very small in size (2.7±0.9?m). Amylose content of wild amadumbe (20%) was about double that of cultivated (12%). By DSC, the peak gelatinisation temperatures of wild and cultivated amadumbe starches were 81 and 85°C, respectively. The slowly digestible starch (SDS); 20% and resistant starch (RS); 64% contents of wild amadumbe appeared slightly higher than those of cultivated. Processing amadumbe into boiled and baked products did not substantially affect SDS and RS contents. Estimated glycaemic index of processed products ranged from 40 to 44%. Thus, amadumbe, both wild and cultivated, present some potential in the formulation of products for diabetics and weight management. PMID:25857954

Naidoo, K; Amonsou, E O; Oyeyinka, S A



Tuberous sclerosis — A multi system disease  

Microsoft Academic Search

Tuberous sclerosis is a genetic disease with autosomal dominant inheritance, associated with hamartomata in several organs\\u000a and various skin findings. A case of a ten year old boy is presented here to highlight the multisystem involvement in tuberous\\u000a sclerosis. The child had seizures, facial papular naevi and periungual fibromas. MRI revealed cortical tubers, white matter\\u000a lesions and subependymal nodules. Orbital

Vijinder Arora; Inderbir Singh Nijjar; Jatinderpal Singh; P. S. Sandhu



Autism in Tuberous Sclerosis Complex  

Microsoft Academic Search

The frequency and clinical presentation of autism in 28 probands with tuberous sclerosis complex (TSC) are reported and risk factors that may influence the development of autism in TSC are examined. Eight probands meet ICD-10 and DSM-IV criteria for autism, an additional 4 meet criteria for pervasive developmental disorder (PDD). Twelve TSC probands with autism\\/PDD are compared to 16 TSC

Griselda C. Gutierrez; Susan L. Smalley; Peter E. Tanguay



Lymphangioleiomyomatosis and Tuberous Sclerosis Complex  

Microsoft Academic Search

Lymphangioleiomyomatosis (LAM) is a rare multisystemic disease of women of child-bearing age and affects mainly the lungs,\\u000a promoting cystic destruction of lung parenchyma or leading to abdominal tumor formation (e.g., angiomyolipomas, lymphangioleiomyomas).\\u000a LAM can arise sporadically or in association with tuberous sclerosis complex (TSC), an autosomal inherited syndrome characterized\\u000a by hamartoma-like tumor growth and pathologic features that are distinct from

Dimitrios Chorianopoulos; Grigoris Stratakos




Technology Transfer Automated Retrieval System (TEKTRAN)

Starch is an inexpensive commodity that has been used for non-food purposes for many years. Some of these uses include cross-linked starches that are synthesized with a variety of multifunctional reagents. One unexplored possibility is the use of azides for cross-linking. To this end, azide deriv...


Direct fermentation of raw starch using a Kluyveromyces marxianus strain that expresses glucoamylase and alpha-amylase to produce ethanol.  


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 ?-amylase from Aspergillus oryzae as well as ?-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. PMID:24478139

Wang, Rongliang; Wang, Dongmei; Gao, Xiaolian; Hong, Jiong



Characterization of Arenga starch in comparison with sago starch.  


The aim of this research was to characterize the composition and physical properties of palm starch obtained from Arenga pinnata in comparison with another palm starch from Metroxylon sago. The amylose contents of both starches were not significantly different. Peak gelatinization temperature was also similar at approximately 67 °C, but arenga starch showed a narrower range of gelatinization temperature than sago. The crystallinity and swelling power capacity of arenga starch were lower than those of sago. Arenga and sago starch paste at low concentrations showed shear thinning behavior, and sago formed a more viscous sol/paste than arenga. The sol-gel transition concentration of sago starch paste was found at a lower concentration than arenga starch. At high concentrations, gel from arenga starch was more rigid than that of sago. The breaking properties and texture profile of both starch gels were also clearly different, suggesting that they are suited for different applications. PMID:23399292

Adawiyah, Dede R; Sasaki, Tomoko; Kohyama, Kaoru



Hormone Metabolism During Potato Tuber Dormancy  

Technology Transfer Automated Retrieval System (TEKTRAN)

At harvest and for an indeterminate period thereafter potato tubers will not sprout and are physiologically dormant. The length of tuber dormancy is dependent on cultivar and pre- and postharvest environmental conditions. Plant hormones have been shown to be involved in all phases of dormancy prog...


Cardiac Rhabdomyoma In Familial Tuberous Sclerosis  

PubMed Central

Cardiac rhabdomyomas are often associated with tuberous sclerosis in infants. We report a 5 month old child presented with a tumor in the right ventricle and echocardiography features of rhabdomyoma. Both the child and her father had cutaneous features of tuberous sclerosis. In the absence of features of congestive heart failure, surgery is rarely required. PMID:24251015

Chaurasia, Amit Kumar; Harikrishnan, S; Bijulal, S; Choudhary, Dinesh; Tharakan, JA



Cardiac rhabdomyoma in familial tuberous sclerosis.  


Cardiac rhabdomyomas are often associated with tuberous sclerosis in infants. We report a 5 month old child presented with a tumor in the right ventricle and echocardiography features of rhabdomyoma. Both the child and her father had cutaneous features of tuberous sclerosis. In the absence of features of congestive heart failure, surgery is rarely required. PMID:24251015

Chaurasia, Amit Kumar; Harikrishnan, S; Bijulal, S; Choudhary, Dinesh; Tharakan, Ja



An Unusual Case of Perinatal Tuberous Sclerosis  

PubMed Central

We report a case of a neonate who presented to us with multiple rhabdomyomas of heart, cortical tubers in the brain and skeletal anomalies such as Pierre Robin sequence, bilateral clubfoot and lower small bowel obstruction. Though a diagnosis of neonatal tuberous sclerosis was made, the association of skeletal anomalies and intestinal obstruction was a rare and unusual finding. PMID:25024981

Hegde, Deeparaj Ganapati; Mondkar, Jayashree; Panchal, Harshad



Potato Tubers and Soil Aeration1  

Microsoft Academic Search

Potato plants are more sensitive to soil oxygen stress than many other common crops. Some recent literature suggests this may be due to a relatively high oxygen requirement for tuber growth, rather than a greater requirement for the roots per se. Consequently, the oxygen consumption of growing potato tubers (Solanum tuberosum cv. Russet Burbank) was measured in the field on

J. W. Cary



Isolation of an amylose-free starch mutant of the potato ( Solanum tuberosum L.)  

Microsoft Academic Search

An amylose-free potato mutant was isolated after screening 12,000 minitubers. These minitubers had been induced on stem segments of adventitious shoots, which had been regenerated on leaf explants of a monoploid potato clone after Röntgen-irradiation. The mutant character is also expressed in subterranean tubers and in microspores. Starch granules from the mutant showed a strongly reduced activity of the granule

J. H. M. Hovenkamp-Hermelink; E. Jacobsen; A. S. Ponstein; R. G. F. Visser; G. H. Vos-Scheperkeuter; E. W. Bijmolt; J. N. Vries; B. Witholt; W. J. Feenstra



Influence of starch structure and starch granule-associated proteins on rheological properties of starch pastes  

Microsoft Academic Search

Components of starch granules were investigated to reveal the roles of components in the overall rheology of starch pastes and gels. In a reconstitution study, replacement of insoluble starch with soluble starch decreased the viscosity of pastes and reduced the stickiness of gels. Rice amylopectin fine structure was found to significantly correlate with paste breakdown. Proportion of long chains of

Xian-Zhong Han



Genetic analysis of pigmented tuber flesh in potato.  


Interest in anthocyanin-pigmented potato tuber flesh is increasing. To genetically map and characterize loci that influence this trait, diploid potato clone 10618-01, which has partially pigmented flesh, was crossed with diploid 320-02, which has white flesh. Almost all progeny exhibited purple coloration in the flesh, with some clones having only a small percentage of tissue pigmented, other clones having most tissue pigmented, and the majority of clones showing intermediate color phenotypes. The two parents and 228 progeny were genotyped with 493 AFLP, 8 CAPS, and 13 SSR markers. QTLs influencing extent of flesh pigmentation were detected on chromosomes 5, 8, and 9. The potato homolog of Petunia an1, a basic helix-loop-helix (bHLH) transcriptional regulator of anthocyanin biosynthesis, was found to co-localize with the QTL on chromosome 9. A CAPS marker based on this gene was used to evaluate a collection of 21 tetraploid potato clones with highly or fully pigmented red or purple flesh, as well as 53 cultivars with white or yellow flesh. All 21 pigmented-flesh clones shared a marker allele that was present in only 21 of the 53 white and yellow clones, suggesting that a common bHLH allele contributes toward, although it is clearly not sufficient for, highly or fully pigmented tuber flesh in cultivated potato. PMID:19363602

Zhang, Yongfei; Jung, Chun Suk; De Jong, Walter S



Multiplex PCR for the identification of white Tuber species  

Microsoft Academic Search

Species-specific primers selected from the internal transcribed spacer region sequence were used to set up a multiplex polymerase chain reaction (PCR) able to simultaneously identify the white truffle species Tuber magnatum, Tuber borchii, Tuber maculatum and Tuber puberulum. Furthermore, a primer specific for the competitive fungus Sphaerosporella brunnea was designed and added to the multiplex PCR set, allowing the detection

Antonella Amicucci; Chiara Guidi; Alessandra Zambonelli; Lucia Potenza; Vilberto Stocchi



Composition and physical properties of starch in microgravity-grown plants  

NASA Technical Reports Server (NTRS)

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.

Kuznetsov, O. A.; Brown, C. S.; Levine, H. G.; Piastuch, W. C.; Sanwo-Lewandowski, M. M.; Hasenstein, K. H.; Sager, J. C. (Principal Investigator)



Composition and physical properties of starch in microgravity-grown plants  

NASA Astrophysics Data System (ADS)

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 ??/?? (?? - difference of magnetic susceptibilities, ?? - 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/cm 3), the observed difference in ??/?? 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 ?-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 ??/?? 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, ??/?? and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity.

Kuznetsov, O. A.; Brown, C. S.; Levine, H. G.; Piastuch, W. C.; Sanwo-Lewandowski, M. M.; Hasenstein, K. H.



Metabolomic analysis of the potato tuber life cycle  

Microsoft Academic Search

An analysis of the potato (Solanum tuberosum L.) tuber life cycle has been completed using a range of mass-spectrometry (MS) based approaches. Six stages have been examined\\u000a which included developing and mature tubers, sprouting mature tubers and mature tubers stored at 5 or 10°C. The impact of\\u000a excising developing tubers from the mother plant (source-sink manipulation) was also determined. Data

L. V. T. Shepherd; C. A. Alexander; J. A. Sungurtas; J. W. McNicol; D. Stewart; H. V. Davies



Comparative disintegrant activities of breadfruit starch and official corn starch  

Microsoft Academic Search

A Comparative evaluation of starch powder extracted from breadfruit (Artocarpus communis, Frost) as tablet disintegrant was made with corn starch BP using a 2×4 factorial experiment in a randomized complete block design. Two factors (type of starch: 2 i.e. breadfruit and corn) at four levels (concentrations of starch disintegrant: 4 i.e. 2.5%, 5%, 7.5% and 10%) were studied. One (1)

Sarafadeen A. Adebayo; Eugenie Brown-Myrie; Oludele A. Itiola



Potato Tuber UDP-Glucose:Protein Transglucosylase Catalyzes Its Own Glucosylation 1  

PubMed Central

Potato (Solanum tuberosum L.) tuber UDP-glucose:protein transglucosylase (UPTG) (EC is involved in the first of a two-step mechanism proposed for protein-bound ?-glucan synthesis by catalyzing the covalent attachment of a single glucose residue to an acceptor protein. The resulting glucosylated 38-kilodalton polypeptide would then serve as a primer for enzymic glucan chain elongation during the second step. In the present report, we describe the fast protein liquid chromatography purification of UPTG from a membrane pellet of potato tuber. An apparently close association of UPTG, phosphorylase, and starch synthase was observed under native conditions during different purification steps. Enrichment of a 38-kilodalton polypeptide was found throughout enzyme purification. It is now shown that the purified UPTG, with an apparent molecular mass of 38 kilodaltons, undergoes self-glucosylation in a UDP-glucose- and Mn2+-dependent reaction. Therefore, it is concluded that UPTG is the enzyme and at the same time the priming protein required for the biogenesis of protein-bound ?-glucan in potato tuber. ImagesFigure 1Figure 2Figure 5Figure 6 PMID:16669042

Ardila, Fernando J.; Tandecarz, Juana S.



Alpine Russet: A potato cultivar having long tuber dormancy making it suitable for processing from long-term storage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alpine Russet is a later maturing, oblong-long, lightly russeted potato cultivar, notable for having tuber dormancy comparable to Russet Burbank. Processing quality of Alpine Russet from long-term storage is superior to Russet Burbank, with low percent reducing sugars and uniform fry color due to a...


The potato tuber mitochondrial proteome.  


Mitochondria are called the powerhouses of the cell. To better understand the role of mitochondria in maintaining and regulating metabolism in storage tissues, highly purified mitochondria were isolated from dormant potato tubers (Solanum tuberosum 'Folva') and their proteome investigated. Proteins were resolved by one-dimensional gel electrophoresis, and tryptic peptides were extracted from gel slices and analyzed by liquid chromatography-tandem mass spectrometry using an Orbitrap XL. Using four different search programs, a total of 1,060 nonredundant proteins were identified in a quantitative manner using normalized spectral counts including as many as 5-fold more "extreme" proteins (low mass, high isoelectric point, hydrophobic) than previous mitochondrial proteome studies. We estimate that this compendium of proteins represents a high coverage of the potato tuber mitochondrial proteome (possibly as high as 85%). The dynamic range of protein expression spanned 1,800-fold and included nearly all components of the electron transport chain, tricarboxylic acid cycle, and protein import apparatus. Additionally, we identified 71 pentatricopeptide repeat proteins, 29 membrane carriers/transporters, a number of new proteins involved in coenzyme biosynthesis and iron metabolism, the pyruvate dehydrogenase kinase, and a type 2C protein phosphatase that may catalyze the dephosphorylation of the pyruvate dehydrogenase complex. Systematic analysis of prominent posttranslational modifications revealed that more than 50% of the identified proteins harbor at least one modification. The most prominently observed class of posttranslational modifications was oxidative modifications. This study reveals approximately 500 new or previously unconfirmed plant mitochondrial proteins and outlines a facile strategy for unbiased, near-comprehensive identification of mitochondrial proteins and their modified forms. PMID:24351685

Salvato, Fernanda; Havelund, Jesper F; Chen, Mingjie; Rao, R Shyama Prasad; Rogowska-Wrzesinska, Adelina; Jensen, Ole N; Gang, David R; Thelen, Jay J; Møller, Ian Max



Starch mutants of Chlamydomonas  

SciTech Connect

Wild type Chlamydomonas accumulates starch and triglycerides when grown under nitrogen limiting conditions. Toward elucidation of the mechanisms for control of starch biosynthesis, we isolated mutants impaired int he accumulation of storage carbohydrates. Chlamydomonas reinhardtii (strain ya-12) was mutagenized by UV irradiation and colonies were screened by iodine staining after growth in darkness. Mutants, denoted ais for altered in iodine staining, have been characterized by electron microscopy and assays for starch synthease, ADPG-pyrophosphorylase, phosphoglucose isomerase (PGI), phosphoglucomutase and fructose 1,6-bisphosphatase, and amylase activities. Transcript analysis of wild type and mutant RNAs with PGI, ADPG-pyrophosphorylase, and waxy probes have also been carried out. No deficiencies of any of these components have been detected. Furthermore, long-term cultures of ya-12 and ais-1d in nitrogen-limited chemostats have been studied; starch also does not accumulate in ais-1d under these conditions. Thus, the lesion affects an essential factor of unknown identity that is required for starch synthesis.

Berry-Lowe, S.L.; Schmidt, G.W. (Univ. of Georgia, Athens (USA))




Technology Transfer Automated Retrieval System (TEKTRAN)

The suberization of tuber wounds and the development of resistance to tuber excoriation (resistance to tuber skinning injury) are important physiological processes that directly impact tuber market quality. However, critical portions of the biochemical processes responsible for suberization and res...


Immunological properties of Andean starch films are independent of their nanometric roughness and stiffness.  


Starch is a natural material extracted from roots, seeds, stems and tubers of different plants. It can be processed as a thermoplastic to produce a variety promising products for biomedical applications, including foams, sheets and films. In the present work, we investigated the immunological properties of microfilms prepared with starches extracted from six different types of Andean potatoes and their relationship with the different film-surface features. We confirmed the biocompatibility of all the films using THP-1 human monocytes, noticing only slight decrease in cell viability in two of the tested starches. We also analyzed pro-inflammatory cytokine release and immune cell surface receptor modulation on THP-1 plated onto the films. Our data show differences in the immunological profile of the same cells cultured onto the different starch films. Furthermore, we examined whether the dissimilar stiffness or the nanometric roughness of the films might influence the immune stimulation of the THP-1 monocytes. Our results demonstrate no correlation between cultured THP-1 immune activation and surface film characteristics. We conclude that different Andean native potato starch films have specific ability to interact with cell membranes of immune cells, conceivably due to the different spatial localization of amylose and amylopectin in the diverse starches. PMID:25697674

Torres, F G; Troncoso, O P; Gamucci, O; Corvaglia, S; Brunetti, V; Bardi, G



The potato developer (D) locus encodes an R2R3 MYB transcription factor that regulates expression of multiple anthocyanin structural genes in tuber skin.  


A dominant allele at the D locus (also known as I in diploid potato) is required for the synthesis of red and purple anthocyanin pigments in tuber skin. It has previously been reported that D maps to a region of chromosome 10 that harbors one or more homologs of Petunia an2, an R2R3 MYB transcription factor that coordinately regulates the expression of multiple anthocyanin biosynthetic genes in the floral limb. To test whether D acts similarly in tuber skin, RT-PCR was used to evaluate the expression of flavanone 3-hydroxylase (f3h), dihydroflavonol 4-reductase (dfr) and flavonoid 3',5'-hydroxylase (f3'5'h). All three genes were expressed in the periderm of red- and purple-skinned clones, while dfr and f3'5'h were not expressed, and f3h was only weakly expressed, in white-skinned clones. A potato cDNA clone with similarity to an2 was isolated from an expression library prepared from red tuber skin, and an assay developed to distinguish the two alleles of this gene in a diploid potato clone known to be heterozygous Dd. One allele was observed to cosegregate with pigmented skin in an F(1) population of 136 individuals. This allele was expressed in tuber skin of red- and purple-colored progeny, but not in white tubers, while other parental alleles were not expressed in white or colored tubers. The allele was placed under the control of a doubled 35S promoter and transformed into the light red-colored cultivar Désirée, the white-skinned cultivar Bintje, and two white diploid clones known to lack the functional allele of D. Transformants accumulated pigment in tuber skin, as well as in other tissues, including young foliage, flower petals, and tuber flesh. PMID:19779693

Jung, Chun Suk; Griffiths, Helen M; De Jong, Darlene M; Cheng, Shuping; Bodis, Mary; Kim, Tae Sung; De Jong, Walter S



Tuberous Sclerosis Complex Diagnostic Criteria Update: Recommendations of the 2012 International Tuberous Sclerosis Complex Consensus Conference  

PubMed Central

BACKGROUND Tuberous sclerosis complex is highly variable in clinical presentation and findings. Disease manifestations continue to develop over the lifetime of an affected individual. Accurate diagnosis is fundamental to implementation of appropriate medical surveillance and treatment. Although significant advances have been made in the past 15 years in the understanding and treatment of tuberous sclerosis complex, current clinical diagnostic criteria have not been critically evaluated or updated since the last clinical consensus conference in 1998. METHODS The 2012 International Tuberous Sclerosis Complex Consensus Group, comprising 79 specialists from 14 countries, was organized into 12 subcommittees, each led by a clinician with advanced expertise in tuberous sclerosis complex and the relevant medical subspecialty. Each subcommittee focused on a specific disease area with important diagnostic implications and was charged with reviewing prevalence and specificity of disease-associated clinical findings and their impact on suspecting and confirming the diagnosis of tuberous sclerosis complex. RESULTS Clinical features of tuberous sclerosis complex continue to be a principal means of diagnosis. Key changes compared with 1998 criteria are the new inclusion of genetic testing results and reducing diagnostic classes from three (possible, probable, and definite) to two (possible, definite). Additional minor changes to specific criterion were made for additional clarification and simplification. CONCLUSIONS The 2012 International Tuberous Sclerosis Complex Diagnostic Criteria provide current, updated means using best available evidence to establish diagnosis of tuberous sclerosis complex in affected individuals. PMID:24053982

Northrup, Hope; Krueger, Darcy A.




Technology Transfer Automated Retrieval System (TEKTRAN)

Surface and interfacial tensions with hexadecane were measured for starch and water soluble starch ester solutions in order to determine their potential as stabilizers or emulsifiers. The surface tension for an acid hydrolysed starch (maltodextrin) initially declined with concentration and then rea...


Starch Phosphorylase Inhibitor from Sweet Potato 1  

PubMed Central

A protein, starch phosphorylase inhibitor, was purified from the root of sweet potato (Ipomoea batatas [L.] Lam. cv Tainon 65). It had a molecular weight of 250,000 and could be composed of five identical subunits. The isoelectric point of the inhibitor was 4.63. It was a noncompetitive inhibitor toward the sweet potato enzyme with a Ki value of 1.3 × 10?6 molar when glucose-1-P was the variable substrate. Because cross-reacting materials of rabbit antiphosphorylase inhibitor of sweet potato were found in three arbitrarily selected plant materials, viz. potato tuber, spinach leaf, and rice grain, the occurrence of this protein seemed universal in higher plants. By an immunofluorescence technique, the inhibitor was located in the amyloplast and cell wall where phosphorylase was also found. This implies that they may interact in vivo, and the inhibitor may play an unknown regulatory role against the plant enzyme. Images Fig. 2 Fig. 3 Fig. 5 Fig. 7 Fig. 8 PMID:16664657

Chang, Tsung-Chain; Su, Jong-Ching



Genetic Improvement of Potato for Tuber Calcium Uptake  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tuber internal quality is a major limiting factor for the U.S. potato industry. Breeders invest time and money in producing advanced selections which, in the end, often fail because of tuber internal defects, tuber bruising, or storage quality issues. In-season fertilization with calcium is known to...



Microsoft Academic Search

The paper reviews the role of starch and biodegradable plastics production in Thailand, emphasizing the potential contribution of cassava starch in these products. Types of biodegradable plastics and their manufacturing processes are described. The major types of biodegradable plastics discussed are directly-expanded starch products and various starch-polymer blends (PCL, PLA, PVA and PHA). Research focusing on cassava starch incorporation into

Klanarong Sriroth; Rungsima Chollakup; Kuakoon Piyachomkwan; Christopher G. Oates


Incidence of hepatic hamartomas in tuberous sclerosis.  

PubMed Central

Hepatic hamartomas were thought to be a rare finding in patients with tuberous sclerosis. The purpose of this study was to assess their incidence in children with tuberous sclerosis and to review the literature. During 1984-90 we examined 51 children by ultrasonography; there were 25 boys and 26 girls. Their age ranged from 3 months to 18 years. Liver hamartomas were seen in 12 (23.5%) of the children, more often in girls than boys (5:1). Their incidence increased with age reaching 45% in children over the age of 10. They did not produce any symptoms of hepatic dysfunction. Our study and review of reported cases prove that hepatic hamartomas are a common finding in patients with tuberous sclerosis and may be very helpful in providing a more accurate diagnosis and consequently help in genetic counselling. PMID:1471887

Jó?wiak, S; Pedich, M; Rajszys, P; Michalowicz, R



Light-colored, Low Acrylamide Potato Chips  

Technology Transfer Automated Retrieval System (TEKTRAN)

Potato tubers are stored at cold temperatures to prevent sprouting, minimize disease losses and increase the marketing window. Cold storage also causes an accumulation of reducing sugars, a phenomenon referred to as cold-induced sweetening. Unacceptable, dark colored chips and fries are formed durin...


Preparation of high-fructose syrup from the tubers of the Jerusalem artichoke (Helianthus tuberosus L.  


Fructose has recently received much attention due to renewed interest in natural sweeteners. In addition, fructose has some advantages to sucrose in sweetness, solubility, viscosity, and dental health characteristics. Fructose is deposited as storage fructans of the inulin (beta-1,2) type in tubers and rhizomes of the Compositae family. The utilization of the Jerusalem artichoke (Helianthus tuberosus) tuber as a source of fructose syrup is discussed. This plant has the potential to produce more sugar per acre than corn or sugar beets. In addition, the artichoke has higher frost resistance and lower heat unit requirements than corn and is somewhat more tolerant to low moisture conditions than sugar beets. A high quality fructose syrup can be produced from artichoke tubers. The extraction step was found to be particularly important since development of adverse colors and flavors must be prevented. The fructans may be acid or enzyme hydrolyzed but the latter method gave a higher quality syrup. Ion-exchange resins and activated charcoal were effective in removing coloring and flavoring materials, and also reduced other noncarbohydrate constituents. Since the enzymatic hydrolysis of the fructans is an attractive alternative to acid hydrolysis, a process was developed for producing and purifying a special beta-fructofuranosidase (inulase) from Saccharomyces fragilis. Inulase has a much higher specificity for fructans than commerically available beta-fructofuranosidase (invertase). PMID:41685

Fleming, S E; GrootWassink, J W



Color Constant Color Indexing  

Microsoft Academic Search

Objects can be recognized on the basis of their color alone by color indexing, a technique developed by Swain-Ballard (1991) which involves matching color-space histograms. Color indexing fails, however, when the incident illumination varies either spatially or spectrally. Although this limitation might be overcome by preprocessing with a color constancy algorithm, we instead propose histogramming color ratios. Since the ratios

Brian V. Funt; Graham D. Finlayson



Current research addressing starch acetylation.  


Though modification of starch through acetylation is known for about 150years, it is still an object of extensive studies at various research centers worldwide. This manuscript presents an overview of literature from the last 5years concerning starch acetylation. It also describes the applied raw materials, production procedures of acetylated starch and correlations between the degree of substitution with acetyl groups and properties of the modified preparations. PMID:25624243

Golachowski, A; Zi?ba, T; Kapelko-?eberska, M; Dro?d?, W; Gryszkin, A; Grzechac, M



Starch digestion capacity of poultry.  


Starch is quantitatively the most important nutrient in poultry diets and will to a large extent be present as intact starch granules due to very limited extent of gelatinization during pelleting. Although native starch is difficult to digest due to a semi-crystalline structure, even fast-growing broiler chickens appears to be able to digest this starch more or less completely during passage through the jejunum. However, reduced starch digestibility has been observed, particularly in pelleted diets containing large quantities of wheat. Although properties of the starch granule such as size and components on the granule surface may affect digestibility, the entrapment of starch granules in cell walls and a protein matrix may be even more important factors impeding starch digestion. In that case, this and the fact that amylase secretion is normally very high in poultry may explain the lack of convincing effects of exogenous ?-amylase added to the diet. However, few well-designed experiments assessing mechanisms of starch digestion and the effect of ?-amylase supplementation have been carried out, and thus more research is needed in this important area. PMID:25012853

Svihus, B



Tuberous Sclerosis Complex Surveillance and Management: Recommendations of the 2012 International Tuberous Sclerosis Complex Consensus Conference  

PubMed Central

BACKGROUND Tuberous sclerosis complex is a genetic disorder affecting every organ system, but disease manifestations vary significantly among affected individuals. The diverse and varied presentations and progression can be life-threatening with significant impact on cost and quality of life. Current surveillance and management practices are highly variable among region and country, reflective of the fact that last consensus recommendations occurred in 1998 and an updated, comprehensive standard is lacking that incorporates the latest scientific evidence and current best clinical practices. METHODS The 2012 International Tuberous Sclerosis Complex Consensus Group, comprising 79 specialists from 14 countries, was organized into 12 separate subcommittees, each led by a clinician with advanced expertise in tuberous sclerosis complex and the relevant medical subspecialty. Each subcommittee focused on a specific disease area with important clinical management implications and was charged with formulating key clinical questions to address within its focus area, reviewing relevant literature, evaluating the strength of data, and providing a recommendation accordingly. RESULTS The updated consensus recommendations for clinical surveillance and management in tuberous sclerosis complex are summarized here. The recommendations are relevant to the entire lifespan of the patient, from infancy to adulthood, including both individuals where the diagnosis is newly made as well as individuals where the diagnosis already is established. CONCLUSIONS The 2012 International Tuberous Sclerosis Complex Consensus Recommendations provide an evidence-based, standardized approach for optimal clinical care provided for individuals with tuberous sclerosis complex. PMID:24053983

Krueger, Darcy A.; Northrup, Hope




Technology Transfer Automated Retrieval System (TEKTRAN)

While the use of acidity by plants for defense against disease is widespread and well known (e.g., acidic fruits), little appears to be known about the range of variation in tissue acidity in potato or its implications. We collected tuber samples in sealable plastic “sandwich” bags, froze them in a ...


Glioblastoma in the setting of tuberous sclerosis.  


Tuberous sclerosis is an autosomal dominant condition commonly manifesting with seizures, mental retardation, cortical tubers and hamartomas. Neoplasms may occasionally arise in this setting with the majority of these tumors being subependymal giant cell astrocytomas (World Health Organization [WHO] grade I). Reports of high grade astrocytic neoplasms arising in patients with tuberous sclerosis are rare. We report a left fronto-parietal mass presenting in a 33-year-old woman with altered mental status and slurred speech. The tumor demonstrated areas of enhancement and was associated with mass effect on CT imaging. The tumor was marked by prominent cellularity, easily identifiable mitotic figures, vascular proliferative changes, necrosis and multinucleated giant cells. A Ki-67 labeling index of greater than 30% was noted. The findings were interpreted as being consistent with a glioblastoma (WHO grade IV). The limited literature on similar cases of malignant gliomas arising in the setting of tuberous sclerosis are reviewed. Few reports of similar tumors have been described in the literature. Presentation appears to depend on where the tumor is situated; locations have been variable in previous reports. For those cases in which survival data were included, the prognosis is poor. PMID:25677876

Reyes, Dennys; Prayson, Richard



Brucite nanoplate reinforced starch bionanocomposites  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this paper the mechanical reinforcement in a series of bionanocomposites films based on starch and nano-sized brucite, Mg(OH)2, was investigated. Brucite nanoplates with an aspect ratio of 9.25 were synthesized by wet precipitation and incorporated into starch matrices at different concentrations...


Developing Biodegradable Plastics from starch  

Microsoft Academic Search

The diversity and ubiquity of plastic products substantially testify to the versatility of the special class of engineering materials known as polymers. However, the non-biodegradability of these petrochemical-based materials has been a source of environmental concerns and hence, the driving force in the search for 'green' alternatives for which starch remains the frontliner. Starch is a natural biopolymer consisting predominantly

Olayide O. Fabunmi; Lope G. Tabil Jr; Satyanarayan Panigrahi; Peter R. Chang


Starch — Value Addition by Modification  

Microsoft Academic Search

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

Rudrapatnam N. Tharanathan



Morphology, structure and gelatinization properties of heterogeneous starch granules from high-amylose maize.  


High-amylose cereal endosperm is rich in heterogeneous starch granules. In this paper, we investigated the morphology, structure and gelatinization properties of high-amylose maize endosperm starch. Starch had individual, aggregate and elongated heterogeneous granules. Most of individual granules were round with small size and had one central hilum. Aggregate and elongated granules consisted of many subgranules with central hila, and had irregular and rod/filamentous shapes, respectively. Iodine stained starch granules showed five types of polarization colors: blue, purple, fuchsia, dark red, and interior dark blue and exterior brown. Most of individual and aggregate granules had the color of dark red, that of elongated granules the color of interior dark blue and exterior brown. Amylose was mainly distributed in the hilum region and the circumference of starch granules. Aggregate and elongated granules had higher amylose content than individual granules. Elongated and individual granules had the highest and the lowest gelatinization resistance among high-amylose maize heterogeneous starch granules, respectively. PMID:24507325

Cai, Canhui; Zhao, Lingxiao; Huang, Jun; Chen, Yifang; Wei, Cunxu



Rheology of Starch Pastes from Starches of Different Origins: Applications to Starch-based Sauces  

Microsoft Academic Search

Starches of four types, from maize (normal, or chemically modified, waxy), wheat (unmodified) and rice (waxy, unmodified), have been investigated under different pasting conditions. The effect of the upper pasting temperature which is known to be of particular importance in the functional properties of starch in industrial processes has been specifically investigated. The rheological properties have been assessed from viscosity

J.-Y Thebaudin; A.-C Lefebvre; J.-L Doublier



Starches, Sugars and Obesity  

PubMed Central

The rising prevalence of obesity, not only in adults but also in children and adolescents, is one of the most important public health problems in developed and developing countries. As one possible way to tackle obesity, a great interest has been stimulated in understanding the relationship between different types of dietary carbohydrate and appetite regulation, body weight and body composition. The present article reviews the conclusions from recent reviews and meta-analyses on the effects of different starches and sugars on body weight management and metabolic disturbances, and provides an update of the most recent studies on this topic. From the literature reviewed in this paper, potential beneficial effects of intake of starchy foods, especially those containing slowly-digestible and resistant starches, and potential detrimental effects of high intakes of fructose become apparent. This supports the intake of whole grains, legumes and vegetables, which contain more appropriate sources of carbohydrates associated with reduced risk of cardiovascular and other chronic diseases, rather than foods rich in sugars, especially in the form of sugar-sweetened beverages. PMID:22254101

Aller, Erik E. J. G.; Abete, Itziar; Astrup, Arne; Martinez, J. Alfredo; van Baak, Marleen A.



Engineering starch for increased quantity and quality  

Microsoft Academic Search

The characterization and production of starch variants from mutation studies and transgene technology has been invaluable for our understanding of the synthesis of the starch granule. The knowledge gained has allowed for genetic manipulation of the starch biosynthetic pathway in plants. This in vivo approach can be used to generate novel starches and diminishes the need for post-harvest chemically and

Casey J Slattery; I. Halil Kavakli; Thomas W Okita



New tuber species found in Poland.  


New information from a survey of truffles carried out in southern part of Poland in September 2007 is presented. The fruit bodies of Tuber aestivum, T. excavatum, T. rufum and one unidentified Tuber sp. were found. The soil chemistry of the five T. aestivum sites was analysed. Our inventory showed that T. aestivum prefers the mixed forest with host-trees such as: Quercus robur, Corylus avellana, Carpinus betulus, Fagus silvaticus and Tilia cordata. Selection of local inocula of T. aestivum for the propagation of truffles production could be an alternative to the Mediterranean truffles orchards in times when demand for the fungi will be increasing. Fruit bodies of truffles are conserved in the collection of biological material in the Forest Research Institute in Sekocin Stary. PMID:18414906

Hilszcza?ska, Dorota; Sierota, Zbigniew; Palenzona, Mario



Identification of Armillaria nabsnona in gastrodia tubers.  


The symbiosis between Armillaria species and an achlorophylous orchid Gastrodia elata BLUME has been reported. The main species described as a symbiont is Armillaria mellea (VAHL: FR.) KUMMER, known widely as a primary root rot pathogen. Samples collected from the rhizomorphs attached to the tuber of G. elata were separated and analyzed. Molecular analysis based on sequencing of the intergenic spacer 1 (IGS-1) and internal transcribed spacer (ITS) regions of the ribosomal DNA (rDNA) was performed, coupled with restriction fragment length polymorphism (RFLP) of the IGS-1 region. Cultural morphology and features of basidiomata were also used to characterize the isolates. Phylogenetic analysis and morphological data strongly suggested that the fungus present in the tubers of G. elata is Armillaria nabsnona. This is the first report of occurrence of this Armillaria species in association with G. elata. PMID:18591784

Sekizaki, Haruo; Kuninaga, Shiro; Yamamoto, Mizuho; Asazu, Sandra Naomi; Sawa, Satoko; Kojoma, Mareshige; Yokosawa, Ryozo; Yoshida, Naotoshi



Selective epilepsy surgery in tuberous sclerosis.  


A patient with tuberous sclerosis diagnosed at the age of 5 years developed an intractable seizure disorder characterized by complex partial seizures numbering 10-20/day. Interictal electroencephalograms (EEG) showed a right frontal epileptogenic focus. A computerized tomography scan demonstrated calcification in the right frontal region at two sites, periventricular calcification and multiple low density lesions. Neuropsychological assessment showed a verbal intelligence quotient (IQ) of 69 and a performance IQ of 88. Telemetry and video monitoring recorded 10 seizures during which the EEG showed flattening of ongoing sharp wave activity in the right frontal region. Electrocorticography further identified and localized epileptogenic tissue in the right frontal cortex and surgical removal of involved tissue and the adjacent two tubers was carried out. Twelve months after surgery the patient has had only two brief seizures. PMID:2511830

Bye, A M; Matheson, J M; Tobias, V H; Mackenzie, R A



Sirolimus for Angiomyolipoma in Tuberous Sclerosis Complex or Lymphangioleiomyomatosis  

Microsoft Academic Search

Background Angiomyolipomas in patients with the tuberous sclerosis complex or sporadic lymphangioleiomyomatosis are associated with mutations in tuberous sclerosis genes resulting in constitutive activation of the mammalian target of rapamycin (mTOR). The drug sirolimus suppresses mTOR signaling. Methods We conducted a 24-month, nonrandomized, open-label trial to determine whether sirolimus reduces the angiomyolipoma volume in patients with the tuberous scle- rosis

John J. Bissler; Francis X. McCormack; Lisa R. Young; Jean M. Elwing; Gail Chuck; Jennifer M. Leonard; Vincent J. Schmithorst; Tal Laor; Alan S. Brody; Judy Bean; Shelia Salisbury; David N. Franz



Overexpression of the sucrose transporter SoSUT1 in potato results in alterations in leaf carbon partitioning and in tuber metabolism but has little impact on tuber morphology.  


The aim of this work was to examine the consequences of the heterologous expression of a spinach ( Spinacia oleracea L.) sucrose transporter ( SoSUT1) in potato ( Solanum tuberosum L.). Many studies have indicated that reduction of the expression of this class of sucrose transporter has deleterious effects on plant growth and development; however, until now the possibility of improving plant performance by enhancing the expression of this sucrose transporter has not been reported. With this intention we constructed a chimeric construct in which SoSUT1 was cloned in-frame with the myc epitope. We confirmed that this construct, SoSUT1m, was able to mediate sucrose transport by expression in the yeast strain SUSY7. SoSUT1m was expressed in wild-type potato in the sense orientation under the control of the cauliflower mosaic virus 35S promoter to evaluate the effect of an increased constitutive expression of a class-I sucrose transporter. We confirmed that these plants displayed expression of SoSUT1 at both the transcript and protein level and that microsomal fragments isolated from selected lines had an increased sucrose uptake capacity. Analysis of metabolism of these lines indicated that the leaves were characterised by a reduced sucrose level yet exhibited little change in photosynthetic rate. Furthermore, despite the observed increase in sugar (and reduction in amino acid) levels within the tubers, there was little change in either starch content or tuber yield in the transformants. In summary, the genetic manipulation described in this paper resulted in a shift in carbon partitioning in both leaves and tubers and an increased sucrose uptake rate in plasma-membrane vesicles isolated from these lines, but had little impact on tuber metabolism or morphology. PMID:12721860

Leggewie, Georg; Kolbe, Anna; Lemoine, Rémi; Roessner, Ute; Lytovchenko, Anna; Zuther, Ellen; Kehr, Julia; Frommer, Wolf B; Riesmeier, Jörg W; Willmitzer, Lothar; Fernie, Alisdair R



Neurologic manifestations of tuberous sclerosis complex  

Microsoft Academic Search

Tuberous sclerosis complex (TSC) is a multiorgan disorder that primarily affects the brain, skin, and kidneys. Recent advances\\u000a have elucidated the genetics of this complex, which has helped lead to an increased understanding of the basic neurobiology\\u000a of this disorder. There is both phenotypic and geneotypic heterogeneity. The treatment of epilepsy remains a major challenge\\u000a in these patients, and there

William M. McClintock



Production of oxalic acid by some fungi infected tubers.  


Oxalic acid (as oxalate) was detected in four tubers commonly used for food in Nigeria-Dioscorea rotundata (White yam), Solanum tuberosum (Irish potato), Ipomoea batatas (Sweet potato), and Manihot esculenta (cassava). Whereas healthy I. batata had the highest oxalic acid content, healthy M. esculenta contained the lowest. When all tubers were artifically inoculated with four fungi-Penicillium oxalicum CURIE and THOM, Aspergillus niger VAN TIEGH, A. flavus and A. tamarii KITA, there was an increase in oxalate content/g of tuber tissue. The greatest amount of oxalate was produced by P. oxalicum in D. rotundata tuber. Consistently higher amounts of oxalate were produced by the four fungi in infected sweet potato tuber than in any other tuber and consistently lower amounts of oxalate were produced by the four fungi in Irish potato tuber. Differences in the carbohydrate type present in the tubers and in the biosynthesis pathway are thought to be responsible for variation in the production of oxalate in the different tubers by the four fungi used. PMID:6670294

Faboya, O; Ikotun, T; Fatoki, O S



Sorghum tannins: Interaction with Starch and its Effects on in vitro Starch Digestibility  

E-print Network

compounds with starch molecules and their effect on in vitro starch digestibility. High tannin (predominant in large molecular weight PA, 80%), black (monomeric polyphenols) and white (low in polyphenols) sorghum phenolic extracts were cooked with starches...

Ribeiro de Barros, Frederico



Hydroxyeyhyl starch: Controversies revisited  

PubMed Central

Hydroxyethyl starch (HES) family has been one of the cornerstones in fluid management for over four decades. Recent evidence from clinical studies and meta-analyses has raised few concerns about the safety of these fluids, especially in certain subpopulations of patients. High-quality clinical trials and meta-analyses have emphasized nephrotoxic effects, increased risk of bleeding, and a trend toward higher mortality in these patients after the use of HES solutions. Scientific evidence was derived from international guidelines, aggregated research literature, and opinion-based evidence was obtained from surveys and other activities (e.g., internet postings). On critical analysis of the current data available, it can be summarized that further large scale trials are still indicated before HES can be discarded. PMID:25425769

Datta, Rashmi; Nair, Rajeev; Pandey, Anil; Kumar, Nitish; Sahoo, Tapan



Color Theory  

NSDL National Science Digital Library

This project will be used to teach the importance of color. Watch the following video about color Primary Colors Click on the link Exploration of Color. When you get into the website select the different colors to see what secondary colors are made from the primary colors. Review the following siteColor Theory and then design and paint a color wheel. ...

Mr. Sturgell



Potato tuber cytokinin oxidase/dehydrogenase genes: Biochemical properties, activity, and expression during tuber dormancy progression  

Technology Transfer Automated Retrieval System (TEKTRAN)

The enzymatic and biochemical properties of the proteins encoded by five potato cytokinin oxidase/dehydrogenase (CKX)-like genes functionally expressed in yeast and the effects of tuber dormancy progression on StCKX expression and cytokinin metabolism were examined in meristems isolated from field-g...


Effect of Shoot Removal During Tuberization on Volunteer Potato (Solanum tuberosum) Tuber Production 1  

Microsoft Academic Search

Volunteer potato can be a host of serious pest problems in potato and could provide a source of inoculum for subsequent potato crops. Volunteer potato can also be difficult to control in many rotational crops. Potato shoots were removed once, twice, and throughout the growing season, beginning at early and late tuberization. Compared with no shoot removal, two or more




Examining the role of tuber biochemistry in the development of zebra chip in stored potato tubers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Zebra chip disease (ZC), associated with infection by the bacterium ‘Candidatus Liberibacter solanacearum’ (Lso), is an emerging problem for potato growers in the United States, Mexico, and New Zealand. Although potato tubers exhibiting ZC symptoms will be rejected by processors, it remains possible...


Genetic variability in mineral content of potato tubers  

Technology Transfer Automated Retrieval System (TEKTRAN)

The contents of eight mineral constituents in the tuber of potato genotypes in Tri-State and Western Regional trials grown at different locations were tested. Tubers were washed free of soil, cleaned with a 1N HCl bath, sliced with skin on, air dried, ground to a fine powder, and wet-ashed in 12 N n...


Root and Tuber Crops in Vietnam: Focus on yam germplasm  

Microsoft Academic Search

Root and tuber crops are the second most important food category after rice in Vietnam. Vietnam has especially rich root crop resources. Root crops play important roles as human food, animal fodder, medicinal material, spices and dyes. The collection and conservation of root and tuber crops germplasm is becoming increasingly urgent. During 1991-2005, many exploration trips were carried out by

Vu Linh Chi; Nguyen Thi; Ngoc Hue; Luu Ngoc Trinh


Neuroepileptic Correlates of Autistic Symptomatology in Tuberous Sclerosis  

ERIC Educational Resources Information Center

Tuberous sclerosis is a genetic condition that is strongly associated with the development of an autism spectrum disorder. However, there is marked variability in expression, and only a subset of children with tuberous sclerosis develop autism spectrum disorder. Clarification of the mechanisms that underlie the association and variability in…

Bolton, Patrick F.




Technology Transfer Automated Retrieval System (TEKTRAN)

Increased calcium (Ca) in potatoes may increase the production rate by enhancing tuber quality and storability. Additionally, increased Ca levels in important agricultural crops may help ameliorate the incidence of osteoporosis. However, the capacity to alter Ca levels in potato tubers through genet...


Observed limit of Solanum jamesii tuber dormancy at 14 years  

Technology Transfer Automated Retrieval System (TEKTRAN)

Control of tuber dormancy is of interest for commercial potato production and for germplasm preservation in the genebank. We previously reported (AJPR 87:226-228) that tubers of greenhouse-grown Solanum jamesii from 1999 sprouted after 8+ years of storage in a continuous 40F (5C) cooler. One populat...


Variation for tuber greening in the wild potato solanum microdontum  

Technology Transfer Automated Retrieval System (TEKTRAN)

Greening of the tuber skin is an undesirable defect. Tubers of 90 Solanum microdontum families represented by 12 individuals each were generated in the winter greenhouse in 2009-2010. These were evaluated in two trials of family bulks after four days of exposure to 200 ft candles of fluorescent whit...


Identification of Tuber magnatum Pico DNA markers by RAPD analysis  

Microsoft Academic Search

Different species of truffle were studied in order to identify species-specific markers. The isolation of two Tuber magnatum Pico markers is reported. One of these could be used as a probe in dot blot hybridization, allowing the development of a rapid test able to identify Tuber magnatum species.

Lucia Potenza; Antonella Amicucci; Ismaela Rossi; Francesco Palma; Roberta Bellis; Paola Cardoni; Vilberto Stocchi



Effect of three viruses on yield, specific gravity, and chip color of potatoes in Maine  

Microsoft Academic Search

Summary  A two-year study was conducted in Maine to measure the effect of three virus diseases on yield, specific gravity, and chip\\u000a color, of the Katahdin and Kennebec potato varieties.\\u000a \\u000a In general, leaf roll reduced yields of tubers the most. Reductions in yields caused by spindle tuber, weak virus X, and severe\\u000a virus X were lower in that order. Yields of

H. J. Murphy; M. J. Goven; D. C. Merriam



Slowly Digestible Starch: Concept, Mechanism, and Proposed Extended Glycemic Index  

Microsoft Academic Search

Starch is the major glycemic carbohydrate in foods, and its nutritional property is related to its rate and extent of digestion and absorption in the small intestine. A classification of starch into rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) based on the in vitro Englyst test is used to specify the nutritional quality of starch.

Genyi Zhang; Bruce R. Hamaker



Lipid metabolism during aging of high-?-linolenate-phenotype potato tubers  

Microsoft Academic Search

Previous studies demonstrated that high levels of ?-linolenate in cell membranes of potato tubers (achieved by overexpressing fatty acid desaturases) enhances lipid peroxidation, oxidative stress, and tuber metabolic rate, effectively accelerating the physiological age of tubers. This study details the changes in lipid molecular species of microsomal and mitochondrial membranes from wild-type (WT) and high-?-linolenate tubers during aging. The microsomal

Vladimir Zabrouskov; N. Richard Knowles



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

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Comparison of Cationic and Unmodified Starches in Reactive Extrusion of Starch-Polyacrylamide Graft Copolymers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Graft copolymers of starch and polyacrylamide (PAAm) were prepared using reactive extrusion in a corotating twin screw extruder. The effect of cationic starch modification was examined using unmodified and cationic dent starch (approximately 23% amylose) and waxy maize starch (approximately 2% amyl...


Quality of Spelt Wheat and its Starch  

Technology Transfer Automated Retrieval System (TEKTRAN)

Flours from 5 spelt cultivars grown over 3 years were evaluated as to their bread baking quality and isolated starch properties. The starch properties included amylose contents, gelatinization temperatures (differential scanning calorimetry), granule size distributions and pasting properties. Mill...


An MRI Study of Cerebellar Volume in Tuberous Sclerosis Complex  

PubMed Central

The cerebellum plays an important role in motor learning and cognition, and structural cerebellar abnormalities have been associated with cognitive impairment. In tuberous sclerosis complex, neurological outcome is highly variable, and no consistent imaging or pathological determinant of cognition has been firmly established. The cerebellum calls for specific attention as mouse models of tuberous sclerosis complex have demonstrated a loss of cerebellar Purkinje cells and cases of human histological data have demonstrated a similar loss in patients. We hypothesized that there might be a common cerebellar finding in tuberous sclerosis complex that could be measured as morphometric changes with magnetic resonance imaging. Using a robust, automated image analysis procedure, we studied 36 patients with tuberous sclerosis complex and age-matched controls and observed significant volume loss among patients in the cerebellar cortices and vermis. Furthermore, this effect was strongest in a subgroup of 19 patients with a known, pathogenic mutation of the tuberous sclerosis 2 gene and impacted all cerebellar structures. We conclude that patients with tuberous sclerosis complex exhibit volume loss in the cerebellum, and this loss is larger and more widespread in patients with a tuberous sclerosis 2 mutation. PMID:23337002

Weisenfeld, Neil I.; Peters, Jurriaan M.; Tsai, Peter T.; Prabhu, Sanjay P.; Dies, Kira A.; Sahin, Mustafa; Warfield, Simon K.



Relationships of hollow heart in Irish potatoes to carbohydrate reabsorption and growth rate of tubers  

Microsoft Academic Search

Tubers of Irish Cobbler that were hollow grew faster than non-hollow tubers on the same plant. However, tubers of varieties\\u000a without hollow heart grew just as rapidly as tubers of the variety with hollow heart. Therefore tuber growth rate was related\\u000a to hollow heart occurring within a variety but could not account for differences between varieties. When plant foliage was

I. J. Crumbly; D. C. Nelson; M. E. Duysen



Rice functionality, starch structure and the genes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Through collaborative efforts among USDA scientists at Beaumont, Texas, we have gained in-depth knowledge of how rice functionality, i.e. the texture of the cooked rice, rice processing properties, and starch gelatinization temperature, are associated with starch-synthesis genes and starch structure...



Technology Transfer Automated Retrieval System (TEKTRAN)

Aqueous starch-oil composites consist of uniformly suspended starch-coated oil droplets (1-10 µm in diameter), and find use in a wide variety of industrial, food, and agricultural applications. One of the main benefits of these starch-oil composites is that they can be drum dried and milled into a ...


Microstructural characterization of yam starch films  

Microsoft Academic Search

Yam starch films were produced by thermal gelatinization of starch suspensions using different starch and glycerol concentrations and were compared to control samples without glycerol. Films were characterized by polarized light microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermomechanical analysis (TMA), X-ray diffraction, water vapor permeability (WVP) and water sorption isotherms. The polarized light microscopy and DSC data

Suzana Mali; Maria Victória E Grossmann; Maria A Garcia; Miriam N Martino; Noemi E Zaritzky




Technology Transfer Automated Retrieval System (TEKTRAN)

Starch is one of the most abundantly available plant-based biopolymer. It is a major component of such high volume commodity crops as corn, potato, and rice. Starch is a highly crystalline, high molecular weight poly(glucose) biopolymer. Starch is insoluble in water in its native state. Various ...


The adsorption of starch derivatives onto kaolin  

Microsoft Academic Search

Modified starches are widely used as binders and thickening agents in paper coating formulations. Frequently, kaolin is used as the coating pigment. In this work, the adsorption of modified starches onto kaolin has been studied.Adsorption behaviour was found to depend both upon the type of chemical modification and botanical orgin. With a phosphate ester of potato starch, adsorption was reduced

J. C. Husband



Properties of Starch Blends with Biodegradable Polymers  

Microsoft Academic Search

Starch, one of the most inexpensive and most readily available of all natural polymers, can be processed into thermoplastic materials only in the presence of plasticizers and under the action of heat and shear. Poor water resistance and low strength are limiting factors for the use of materials manufactured only from starch, and hence the modification of starch is often

Xiu-Li Wang; Ke-Ke Yang; Yu-Zhong Wang




Technology Transfer Automated Retrieval System (TEKTRAN)

Maize kernels of self-pollinated inbred line B73, grown in Ames IA, were harvested on 0, 5, 6, 8, 10 12, 14, 20 and 30 days after pollination (DAP). The kernels were used for starch granule development studies. Starch in the endosperm was first observed on 6 DAP. Starch granules in the kernels th...


Esterification of Starch in Ionic Liquids  

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Molecular Structure of a Low-Amylopectin Starch and Other High-Amylose Maize Starches  

Microsoft Academic Search

The molecular structure of two commercially available high-amylose maize starches, HYLON® V starch and HYLON® VII starch, and of a newly developed low-amylopectin starch (LAPS) was examined. These high-amylose starches give three apparent fractions as determined by gel-permeation chromatography: a high-molecular weight (mol.wt) amylopectin fraction, a low-mol.wt amylose fraction, and an intermediate-mol.wt fraction which contains both linear and branched components.

Yong-Cheng Shi; Terri Capitani; Peter Trzasko; Roger Jeffcoat



The Calcium Solution: Developing Potato Cultivars With Enhanced Tuber Storage and Internal Quality by Genetic Improvement of Tuber Calcium Accumulation Ability Enetic Improvement of Potato for Tuber Calcium Uptake  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tuber internal quality is a major limiting factor for the U.S. potato industry. Breeders invest time and money in producing advanced selections which, in the end, often fail because of tuber internal defects, tuber bruising, or storage quality issues. In-season fertilization with calcium is known to...


Starch Characteristics Influencing Resistant Starch Content of Cooked Buckwheat Groats  

Technology Transfer Automated Retrieval System (TEKTRAN)

Enzyme resistant starch (RS), owing to its health benefits such as colon cancer inhibition, reduced glycemic response, reduced cholesterol level, prevention of gall stone formation and obesity, has received an increasing attention from consumers and food manufacturers, whereas intrinsic and extrinsi...


[Tuberous sclerosis: evaluation of myofibroblasts in cutaneous angiofibromas - case report].  


Tuberous sclerosis is a rare autosomal dominant disorder. Myofibroblasts are cells with a hybrid phenotype between fibroblasts and smooth muscle cells. The objective of this study is to describe clinical and histopathological characteristics of tuberous sclerosis and to conduct an immunohistochemical evaluation of myofibroblasts in cutaneous angiofibromas present in this condition. Lesion sections removed were stained with hematoxylin-eosin and Masson's trichrome. Immunohistochemistry against alpha-SMA was done to determine the presence of myofibroblasts, and the reaction was negative. Since alpha-SMA is a specific marker for myofibroblasts, this result suggests that myofibroblasts are not involved in cutaneous angiofibromas present in the tuberous sclerosis case reported. PMID:20464093

Perez, Erick Gomes; Paranaíba, Lívia Ribeiro; Bonan, Paulo Rogério; Orsi Júnior, Julian Miranda; Oliveira, Adriano Macedo de; Martelli Júnior, Hercílio



Regulation of Bud Rest in Tubers of Potato, Solanum tuberosum L  

PubMed Central

The rest period of the potato tuber was studied in relation to certain biochemical changes that are induced by gibberellic acid (GA3). The concentration of reducing sugars in excised plugs with buds treated with 10?4m GA3 decreased in the first 4 hours after treatment and then rapidly increased up to 70 hours. The pattern in control buds was similar, but the changes occurred more slowly. The response to GA3 is temperature-dependent and is not limited to any particular tissue of the tuber. The concentration of reducing sugars in excised buds increased proportionally to the log of the concentration of GA3 in a range from 10?8 to 10?4m. At 10?3m, GA3 slightly inhibited production of reducing sugars. Malonate inhibits the initial decrease and the subsequent increase in reducing sugars in control buds, but not the increase induced by GA3. Total protein in buds was not influenced by 10?4m GA3 over a period of 40 hours, nor did activity of ?-amylase increase significantly until 20 hours after beginning of treatment. Invertase activity was present initially and, in the presence of GA3, increased after 20 hours. GA3 had no effect on starch phosphorylase activity, which was always present and remained steady over the 20-hour test period. In short term experiments the rate of protein synthesis and synthesis of specific protein fractions were not affected by 10?4m GA3, as measured by the incorporation of l-phenylalanine-U-14C or by experiments with 14C- and 3H- labeled l-phenylalanine or l-leucine. PMID:16657283

Clegg, M. D.; Rappaport, Lawrence



Regulatory role of polyamine in the acid phosphatase from potato tubers.  


Effects of polyamine and metal ions on the new type of acid phosphatase purified from potato (Solanum tuberosum L. Irish Cobbler) tubers were analyzed. The enzyme belongs to nonspecific acid phosphatase family (EC, which hydrolyzes various phosphorylated substrates. The enzyme hydrolyzed inorganic pyrophosphate as a preferred substrate, and exhibited the hyperbolic kinetics with respect to the substrate, inorganic pyrophosphate in the absence of metal cations. Polyamine activated the enzyme effectively by lowering the K(m) value without appreciable changes in the maximal velocity. The most effective polyamines as activators were spermine and spermidine. Mg(2+) ion increased the K(m) value without affecting the maximal velocity of the enzyme, but Ca(2+) ion decreased both the K(m) and V(max) values. Increasing concentrations of spermine also decreased the K(m) value irrespective of Mg(2+) ion included, but gave a constant K(m) and V(max) values in the absence and presence of Ca(2+) ion. Action of spermine and metal ions can be explained by the complex formation with the substrate pyrophosphate. The acid phosphatase from potato can utilize the pyrophosphate-spermine or pyrophosphate-Ca(2+) complex as the preferred substrates. However, the enzyme can use the pyrophosphate-Mg complex with a weak affinity for the active site. Polyamine activates acid phosphatase in the absence and presence of metal cations, and activation by polyamine of the enzyme may contribute to the stimulation of starch biosynthesis and the control of glycolysis/gluconeogenesis by regulating PPi levels in growing potato tubers. PMID:16531056

Tanemura, Yasuko; Yoshino, Masataka



Gene expression analysis of tuberous sclerosis complex cortical tubers reveals increased expression of adhesion and inflammatory factors  

PubMed Central

Cortical tubers in patients with tuberous sclerosis complex are associated with disabling neurological manifestations, including intractable epilepsy. While these malformations are believed to result from the effects of TSC1 or TSC2 gene mutations, the molecular mechanisms leading to tuber formation, as well as the onset of seizures remain largely unknown. We used the Affymetrix Gene Chip platform to provide the first genome wide investigation of gene expression in surgically resected tubers, compared with histological normal perituberal tissue from the same patients or autopsy control tissue. We identified 2501 differentially expressed genes in cortical tubers compared with autopsy controls. Expression of genes associated with cell adhesion e.g., VCAM1, integrins and CD44, or with the inflammatory response, including complement factors, serpinA3, CCL2 and several cytokines, was increased in cortical tubers, whereas genes related to synaptic transmission e.g., the glial glutamate transporter GLT-1, and voltage-gated channel activity, exhibited lower expression. Gene expression in perituberal cortex was distinct from autopsy control cortex suggesting that even in the absence of tissue pathology the transcriptome is altered in TSC. Changes in gene expression yield insights into new candidate genes that may contribute to tuber formation or seizure onset, representing new targets for potential therapeutic development. PMID:19912235

Boer, Karin; Crino, Peter B.; Gorter, Jan A.; Nellist, Mark; Jansen, Floor E.; Spliet, Wim G.M.; van Rijen, Peter C.; Wittink, Floyd R.A.; Breit, Timo M.; Troost, Dirk; Wadman, Wytse J.; Aronica, Eleonora



Improved resolution of major clades within Tuber and taxonomy of species within the Tuber gibbosum complex.  


Tuber gibbosum Harkn., described from northern California, originally was thought to be a single, variable species that fruited from autumn through winter to spring. It has become popular as a culinary truffle in northwestern USA, where it is commercially harvested. Morphological studies suggested it might be a complex that includes at least two species. We conducted morphological and phylogenetic studies of the complex to determine how many species it might contain and how they differed morphologically, geographically and seasonally. We also provide the first LSU phylogeny for the genus Tuber. Phylogenetic analyses resolve nine major clades in the genus with high bootstrap support and distinguish the Gibbosum clade from the Aestivum, Excavatum, Macrosporum, Magnatum, Melanosporum, Puberulum, Rufum and Spinoreticulatum clades. Further analyses of ITS and LSU regions revealed four distinct species in the Gibbosum complex. Although morphologically similar the four species differ in spore size and shape and in peridial anatomy. These species share the synapomorphy of having suprapellis hyphae with distinctive, irregular wall swellings at maturity; we have not seen this hyphal type in any other Tuber spp. worldwide. The three new species are named and described as T. bellisporum Bonito & Trappe, T. castellanoi Bonito & Trappe and T. oregonense Trappe, Bonito & Rawlinson. PMID:20943504

Bonito, Gregory; Trappe, James M; Rawlinson, Pat; Vilgalys, Rytas



Starch grains reveal early root crop horticulture in the Panamanian tropical forest.  


Native American populations are known to have cultivated a large number of plants and domesticated them for their starch-rich underground organs. Suggestions that the likely source of many of these crops, the tropical forest, was an early and influential centre of plant husbandry have long been controversial because the organic remains of roots and tubers are poorly preserved in archaeological sediments from the humid tropics. Here we report the occurrence of starch grains identifiable as manioc (Manihot esculenta Crantz), yams (Dioscorea sp.) and arrowroot (Maranta arundinacea L.) on assemblages of plant milling stones from preceramic horizons at the Aguadulce Shelter, Panama, dated between 7,000 and 5,000 years before present (BP). The artefacts also contain maize starch (Zea mays L.), indicating that early horticultural systems in this region were mixtures of root and seed crops. The data provide the earliest direct evidence for root crop cultivation in the Americas, and support an ancient and independent emergence of plant domestication in the lowland Neotropical forest. PMID:11057665

Piperno, D R; Ranere, A J; Holst, I; Hansell, P



Synthesis and characterization of carboxymethyl potato starch and its application in reactive dye printing.  


Carboxymethyl potato starch (CMPS) was synthesized with a simple dry and multi-step method as a product of the reaction of native potato starch and monochloroacetic acid in the presence of sodium hydroxide. The influence of the molar ratio of sodium hydroxide to anhydroglucose unit, the volume of 95% (v/v) ethanol, the rotation rate of motor driven stirrer and the reaction time for degree of substitution (DS) were evaluated. The product was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffractometry (XRD). FTIR spectrometry showed new bonds at 1618 and 1424 cm?¹ when native starch underwent carboxymethylation. SEM pictures showed that the smooth surface of native starch particles was mostly ruptured. XRD revealed that starch crystallinity was reduced after carboxymethylation. The viscosity of the mixture paste of carboxymethyl starch and sodium alginate (SA) was measured using a rotational viscometer. In addition, the applied effect of mixed paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with SA. And the results indicated that the mixed paste could partially replace SA as thickener in reactive dye printing. The study also showed that the method was low cost and eco-friendly and the product would have an extensive application in reactive dye printing. PMID:22782070

Zhang, Bing; Gong, Honghong; Lü, Shaoyu; Ni, Boli; Liu, Mingzhu; Gao, Chunmei; Huang, Yinjuan; Han, Fei



Color blindness  


Color deficiency; Blindness - color ... Color blindness occurs when there is a problem with the pigments in certain nerve cells of the eye that sense color. These cells are called cones. They are found ...


Color Blindness  


... three color cone cells to determine our color perception. Color blindness can occur when one or more ... Anyone who experiences a significant change in color perception should see an ophthalmologist (Eye M.D.). Next ...


Annealing properties of rice starch.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Thermal properties of starch can be modified by annealing, i.e., a pre-treatment in excessive amounts of water at temperatures below the gelatinization temperatures. This treatment is known to improve the crystalline properties, and is a useful tool to gain a better control of the functional proper...


Hydrothermal modification of rice starches.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rice starch of long grain and waxy cultivars were annealed (ANN) in excess water at 50 oC for 4 hrs. They were also modified under heat-moisture treatment (HMT) conditions at 110 oC, and various moisture contents (20%, 30%, and 40%) for 8 hrs. These treatments altered the pasting and gelling prope...



Technology Transfer Automated Retrieval System (TEKTRAN)

Extruded films of plasticized starch were doped with metal halides in order to produce solid polymer electrolytes. The electrical conductance of the material was increased from 10 exp(-11) S/cm to 10 exp(-6) S/cm. The type and amount of dopant affects the conductance of the material. Although the...


New roles for Notch in tuberous sclerosis  

PubMed Central

Tuberous sclerosis complex (TSC) is a dominantly inherited disease that is characterized by the growth of multiple benign tumors that are often difficult to treat. TSC is caused by mutations that inactivate the TSC1 or TSC2 genes, which normally function to inhibit activation of mammalian target of rapamycin signaling. In this issue of the JCI, two studies reported by Karbowniczek et al. and Ma et al. link TSC inactivation with activated Notch signaling (see the related articles beginning on pages 93 and 103, respectively). Using a variety of approaches, both studies show that inactivation of TSC leads to Notch1 activation. Furthermore, studies in tumor cells suggest that inhibiting Notch slows growth of the tumor cells. Although much remains to be learned about the precise mechanisms by which TSC loss leads to Notch activation, the newly identified link of TSC to Notch provides the rationale for testing Notch inhibitors in TSC-associated tumors. PMID:20038806

Pear, Warren S.



New roles for Notch in tuberous sclerosis.  


Tuberous sclerosis complex (TSC) is a dominantly inherited disease that is characterized by the growth of multiple benign tumors that are often difficult to treat. TSC is caused by mutations that inactivate the TSC1 or TSC2 genes, which normally function to inhibit activation of mammalian target of rapamycin signaling. In this issue of the JCI, two studies reported by Karbowniczek et al. and Ma et al. link TSC inactivation with activated Notch signaling (see the related articles beginning on pages 93 and 103, respectively). Using a variety of approaches, both studies show that inactivation of TSC leads to Notch1 activation. Furthermore, studies in tumor cells suggest that inhibiting Notch slows growth of the tumor cells. Although much remains to be learned about the precise mechanisms by which TSC loss leads to Notch activation, the newly identified link of TSC to Notch provides the rationale for testing Notch inhibitors in TSC-associated tumors. PMID:20038806

Pear, Warren S



Mechanical, barrier and morphological properties of starch nanocrystals-reinforced pea starch films.  


To characterize the pea starch films reinforced with waxy maize starch nanocrystals, the mechanical, water vapor barrier and morphological properties of the composite films were investigated. The addition of starch nanocrystals increased the tensile strength of the composite films, and the value of tensile strength of the composite films was highest when starch nanocrystals content was 5% (w/w). The moisture content (%), water vapor permeability, and water-vapor transmission rate of the composite films significantly decreased as starch nanocrystals content increased. When their starch nanocrystals content was 1-5%, the starch nanocrystals dispersed homogeneously in the composite films, resulting in a relatively smooth and compact film surface and better thermal stability. However, when starch nanocrystals content was more than 7%, the starch nanocrystals began to aggregate, which resulted in the surface of the composite films developing a longitudinal fibrous structure. PMID:25659684

Li, Xiaojing; Qiu, Chao; Ji, Na; Sun, Cuixia; Xiong, Liu; Sun, Qingjie



The expression of a recombinant glycolate dehydrogenase polyprotein in potato (Solanum tuberosum) plastids strongly enhances photosynthesis and tuber yield.  


We have increased the productivity and yield of potato (Solanum tuberosum) by developing a novel method to enhance photosynthetic carbon fixation based on expression of a polyprotein (DEFp) comprising all three subunits (D, E and F) of Escherichia coli glycolate dehydrogenase (GlcDH). The engineered polyprotein retained the functionality of the native GlcDH complex when expressed in E. coli and was able to complement mutants deficient for the D, E and F subunits. Transgenic plants accumulated DEFp in the plastids, and the recombinant protein was active in planta, reducing photorespiration and improving CO2 uptake with a significant impact on carbon metabolism. Transgenic lines with the highest DEFp levels and GlcDH activity produced significantly higher levels of glucose (5.8-fold), fructose (3.8-fold), sucrose (1.6-fold) and transitory starch (threefold), resulting in a substantial increase in shoot and leaf biomass. The higher carbohydrate levels produced in potato leaves were utilized by the sink capacity of the tubers, increasing the tuber yield by 2.3-fold. This novel approach therefore has the potential to increase the biomass and yield of diverse crops. PMID:24605946

Nölke, Greta; Houdelet, Marcel; Kreuzaler, Fritz; Peterhänsel, Christoph; Schillberg, Stefan



Process for producing vegetative and tuber growth regulator  

NASA Technical Reports Server (NTRS)

A process of making a vegetative and tuber growth regulator. The vegetative and tuber growth regulator is made by growing potato plants in a recirculating hydroponic system for a sufficient time to produce the growth regulator. Also, the use of the vegetative and growth regulator on solanaceous plants, tuber forming plants and ornamental seedlings by contacting the roots or shoots of the plant with a sufficient amount of the growth regulator to regulate the growth of the plant and one more of canopy size, plant height, stem length, internode number and presence of tubers in fresh mass. Finally, a method for regulating the growth of potato plants using a recirculating hydroponic system is described.

Stutte, Gary W. (Inventor); Yorio, Neil C. (Inventor)



Root architecture and root and tuber crop productivity.  


It is becoming increasingly evident that optimization of root architecture for resource capture is vital for enabling the next green revolution. Although cereals provide half of the calories consumed by humans, root and tuber crops are the second major source of carbohydrates globally. Yet, knowledge of root architecture in root and tuber species is limited. In this opinion article, we highlight what is known about the root system in root and tuber crops, and mark new research directions towards a better understanding of the relation between root architecture and yield. We believe that unraveling the role of root architecture in root and tuber crop productivity will improve global food security, especially in regions with marginal soil fertility and low-input agricultural systems. PMID:24630073

Villordon, Arthur Q; Ginzberg, Idit; Firon, Nurit



Glucosyloxybenzyl 2-Isobutylmalates from the tubers of Gymnadenia conopsea.  


Seven new glucosyloxybenzyl 2-isobutylmalates, gymnosides I-VII (1-7), were isolated from the tubers of Gymnadenia conopsea. The structures of 1-7 were determined on the basis of chemical and physicochemical evidence. PMID:16792404

Morikawa, Toshio; Xie, Haihui; Matsuda, Hisashi; Yoshikawa, Masayuki



[Bourneville tuberous sclerosis manifested by prenatal finding of intracardiac tumors].  


Neonatal cardiac rhabdomyoma is the most frequent cardiac tumour in the newborn, and a classical way to diagnose tuberous sclerosis (Bourneville's disease). The authors report 4 cases, including 2 antenatal diagnosis: 2 of them had arrhythmia, one with asystolic cardiac failure and the other with cyanosis due to a right-left shunt; the tumour was asymptomatic in the 2 others. The 4 babies had clinical and radiological neurologic signs of tuberous sclerosis, initially or during the course of the disease. The authors discuss the polymorphism of the clinical presentation of tuberous sclerosis in the newborn. Although tuberous sclerosis is transmitted through a dominant gene, the expressivity and the penetrance are very variable. The authors discuss the examination and investigation of at risk family members. The genetic counsel is difficult but very important because of the poor neurologic prognosis of the disease. PMID:1329012

Destuynder, R; Menget, A; Fromentin, C; Burguet, A; Noir, A; Bernard, Y; Feldmann, M; Maucler Jolly, R



Multiple pulmonary artery aneurysms in tuberous sclerosis complex  

PubMed Central

Tuberous sclerosis complex (TSC) is a rare genetic disorder characterised by multiple hamartomas, caused by inactivating mutations of the TSC1/TSC2 tumour suppressor genes. Classical pulmonary involvement in tuberous sclerosis complex (TSC) consists of lymphangioleiomyomatosis and/or multiple micronodular pneumocyte hyperplasia (MMPH). Association of TSC with pulmonary artery aneurysm (PAA) has been only exceptionally described. We report here the first case of TSC with multiple PAA in combination with MMPH, cardiac rhabdomyomas and bone, skin and brain involvement. PMID:23341583

Dunet, Vincent; Qanadli, Salah Dine; Lazor, Romain; Beigelman-Aubry, Catherine



Freezing behavior of potato ( Solanum tuberosum ) tubers in soil  

Microsoft Academic Search

Volunteer potatoes are a major weed problem in potato rotations in regions with mild winter soil temperatures. Freezing dynamics\\u000a of potato tubers in air have been previously reported, but freezing dynamics of tubers in soil may differ due to ice nucleation\\u000a sites and soil water associated with soil. Laboratory experiments conducted in hydrated and dry soil columns and field experiments

R. A. Boydston; M. D. Seymour; C. R. Brown; A. K. Alva



Specific gravity of different zones within potato tubers  

Microsoft Academic Search

Summary and Conclusions  The specific gravity of three concentric zones within tubers of 19 potato varieties was determined over the two-year period\\u000a 1956–1957. During this study, a clear pattern emerged. In varieties where specific gravity of the entire tuber was high there\\u000a was a large difference in spcific gravity between zone three (pith) and the two outer zones. In varieties with

M. K. Sharma; D. R. Isleib; S. T. Dexter



Cyperus Tubers Protect Meloidogyne incognita from 1,3-Dichloropropene.  


Meloidogyne incognita-infected and noninfected tubers of yellow nutsedge (Cyperus esculentus) and purple nutsedge (Cyperus rotundus) were treated with 56 L/ha 1,3-dichloropropene (1,3-D) in microplots and subsequently examined for tuber and nematode viability in the greenhouse using a chile pepper (Capsicum annuum) bioassay system. The study was conducted three times. Nutsedge tuber viability and M. incognita harbored in both yellow and purple nutsedge tubers were unaffected by 1,3-D treatment. Nematode reproduction on nutsedges and associated chile pepper plants varied among years, possibly due to differing levels of tuber infection or soil temperature, but was not affected by fumigation. The presence of M. incognita resulted in greater yellow nutsedge tuber germination and reproduction. The efficacy of 1,3-D for management of M. incognita in chile pepper production is likely to be reduced when nutsedges are present in high numbers, reinforcing the importance of managing these weeds and nematodes simultaneously. PMID:19262797

Thomas, S H; Schroeder, J; Murray, L W



Effect of granular characteristics on pasting properties of starch blends.  


Pasting and morphology properties of starch blends composed of waxy (waxy rice and waxy corn) and non-waxy (normal corn, tapioca and potato) starches at various ratios were investigated for elucidating effect of granular characteristics on pasting of blends. Pasting profiles of blends were between those of the component starches alone, while the changes varied with starch source. Results reveal obvious water competition during pasting for blends composed of waxy starch and highly swelling non-waxy (tapioca or potato) starch. On the contrary, starch blends composed of waxy starch and non-waxy (normal corn) starch with restricted swelling showed less water competition during pasting, and the pasting attributes could be estimated from those of the component starches following the mixing ratio. Results indicate that the pasting properties of starch blends composed of waxy and non-waxy starches depend on not only the mixing ratio, but also the granular characteristics of component starch. PMID:24053839

Lin, Jheng-Hua; Kao, Wen-Tsu; Tsai, You-Che; Chang, Yung-Ho



Starch and cellulose nanocrystals together into thermoplastic starch bionanocomposites.  


In the present work, thermoplastic maize starch based bionanocomposites were prepared as transparent films, plasticized with 35% of glycerol and reinforced with both waxy starch (WSNC) and cellulose nanocrystals (CNC), previously extracted by acidic hydrolysis. The influence of the nanofiller content was evaluated at 1 wt.%, 2.5 wt.% and 5 wt.% of WSNC. The effect of adding the two different nanoparticles at 1 wt.% was also investigated. As determined by tensile measurements, mechanical properties were improved at any composition of WSNC. Water vapour permeance values maintained constant, whereas barrier properties to oxygen reduced in a 70%, indicating the effectiveness of hydrogen bonding at the interphase. The use of CNC or CNC and WSNC upgraded mechanical results, but no significant differences in barrier properties were obtained. A homogeneous distribution of the nanofillers was demonstrated by atomic force microscopy, and a shift of the two relaxation peaks to higher temperatures was detected by dynamic mechanical analysis. PMID:25498612

González, Kizkitza; Retegi, Aloña; González, Alba; Eceiza, Arantxa; Gabilondo, Nagore



Physical association of starch biosynthetic enzymes with starch granules of maize endosperm. Granule-associated forms of starch synthase I and starch branching enzyme II.  

PubMed Central

Antibodies were used to probe the degree of association of starch biosynthetic enzymes with starch granules isolated from maize (Zea mays) endosperm. Graded washings of the starch granule, followed by release of polypeptides by gelatinization in 2% sodium dodecyl sulfate, enables distinction between strongly and loosely adherent proteins. Mild aqueous washing of granules resulted in near-complete solubilization of ADP-glucose pyrophosphorylase, indicating that little, if any, ADP-glucose pyrophosphorylase is granule associated. In contrast, all of the waxy protein plus significant levels of starch synthase I and starch branching enzyme II (BEII) remained granule associated. Stringent washings using protease and detergent demonstrated that the waxy protein, more than 85% total endosperm starch synthase I protein, and more than 45% of BEII protein were strongly associated with starch granules. Rates of polypeptide accumulation within starch granules remained constant during endosperm development. Soluble and granule-derived forms of BEII yielded identical peptide maps and overlapping tryptic fragments closely aligned with deduced amino acid sequences from BEII cDNA clones. These observations provide direct evidence that BEII exits as both soluble and granule-associated entities. We conclude that each of the known starch biosynthetic enzymes in maize endosperm exhibits a differential propensity to associate with, or to become irreversibly entrapped within, the starch granule. PMID:8754683

Mu-Forster, C; Huang, R; Powers, J R; Harriman, R W; Knight, M; Singletary, G W; Keeling, P L; Wasserman, B P



Thermal and rheological properties of breadfruit starch.  


The thermal and rheological properties of breadfruit starch were studied using DSC and 2 different rheometers. It was found that the gelatinization temperature of starch with excess moisture content (>70%) was at approximately 75 °C. A new endotherm was detected at about 173 °C when the moisture content was lower than required for full gelatinization of the starch. A detailed examination revealed that this endotherm represented the melting of amylose-lipid complexes. Breadfruit starch paste exhibited shear-thinning fluid characteristics, and good thermal and pH stability. The setback viscosity of the breadfruit starch was lower than that of potato and corn starches. The rheological properties of the breadfruit starch paste was well described by the Herschel-Bulkley model at a shear rate of 0 to 100 s(-1), where R(2) is greater than 0.95, and it behaved like a yield-pseudoplastic fluid. Both the storage modulus and loss modulus of the paste initially increased sharply, then dropped after reaching the gelatinization peak. Breadfruit starch gel showed both flexibility and viscosity. Suspension with 6% starch content exhibited very weak gel rigidity; however, this increased significantly at starch contents above 20%. PMID:21535676

Wang, Xueyu; Chen, Ling; Li, Xiaoxi; Xie, Fengwei; Liu, Hongshen; Yu, Long



Effects of postharvest curing treatment on flesh color and phenolic metabolism in fresh-cut potato products  

Technology Transfer Automated Retrieval System (TEKTRAN)

The flesh color and phenolic metabolism in potato tuber during curing and after cut were investigated. Result indicated that postharvest curing not only changed phenolic metabolism during curing, but also improved fresh-cut color for 12 days after fresh cut. Significantly lower PAL and higher phenol...


Starch-Based Plastic Foams From Various Starch Sources1  

Microsoft Academic Search

Cereal Chem. 73(5):601-604 Corn, tapioca, wheat, rice, and potato starches were extruded with grafted as was confirmed by X-ray diffraction patterns of extrudates and 30% polystyrene and 5% magnesium silicate or 1% polycarbonate or water solubility indexes. The expansion, unit density and water solubility 0.5% azodicarbonamide in a single screw C. W. Brabender laboratory index of the extrudates depended on



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

PubMed Central

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 ?-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

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



Colored Shadows  

NSDL National Science Digital Library

In this optics activity, learners discover that not all shadows are black. Learners explore human color perception by using colored lights to make additive color mixtures. With three colored lights, learners can make shadows of seven different colors. They can also explore how to make shadows of individual colors, including black. Use this activity demonstrate how receptors in the retina of the eye work to see color.



In situ analysis of enzymes involved in sucrose to hexose-phosphate conversion during stolon-to-tuber transition of potato.  


An in situ study of enzymes involved in sucrose to hexose-phosphate conversion during in vitro stolon-to-tuber transition of potato (Solanum tuberosum L. cv. Bintje) was employed to follow developmental changes in spatial patterns. In situ activity of the respective enzymes was visualized by specific activity-staining techniques and they revealed distinct spatially and developmentally regulated patterns. Two of the enzymes studied were also subject to in situ investigations at the transcriptional level. During the stages of stolon formation high hexokinase (EC and acid (cell wall-bound) invertase (EC activities were restricted to the mitotically active (sub)apical region, suggesting a possible importance of these enzymes for cell division. At the onset of tuberization sucrose synthase (EC and fructokinase (EC were strongly induced (visualized at transcriptional and translational level) and the acid invertase activities disappeared from the swelling subapical region as expected. The high degree of similarity in the spatial pattern and the temporal induction of sucrose synthase and fructokinase suggests a tightly co-ordinated coarse (up)regulation, which may be subject to a sugar-modulated mechanism(s) by which genes involved in the metabolic sucrose-starch converting potential are co-ordinately regulated during tuber growth. The overall activity of uridine-5-diphosphoglucose pyrophosphorylase (EC was present in all tissues during stolon and tuber development, implying that its coarse control is not subject to (in)direct developmental regulation. PMID:12060250

Appeldoorn, Niek J.G; Sergeeva, Lidiya; Vreugdenhil, Dick; Van Der Plas, Linus H.W; Visser, Richard G.F




Technology Transfer Automated Retrieval System (TEKTRAN)

Graft copolymers of polyacrylamide and various substrates were prepared by reactive extrusion in a twin screw extruder using ammonium persulfate as initiator. Substrates included unmodified starches (corn, waxy maize, wheat, and potato), cationic starches, dextrin, dextran, and polyvinyl alcohol (P...


Characterization of starch films containing starch nanoparticles: part 1: physical and mechanical properties.  


We report, for the first time, the preparation method and characteristics of starch films incorporating spray dried and vacuum freeze dried starch nanoparticles. Physical properties of these films such as morphology, crystallinity, water vapor permeability (WVP), opacity, and glass transition temperature (Tg) and mechanical properties (strain versus temperature, strain versus stress, Young's modulus and toughness) were measured. Addition of both starch nanoparticles in starch films increased roughness of surface, lowered degree of crystallinity by 23.5%, WVP by 44% and Tg by 4.3°C, respectively compared to those of starch-only films. Drying method used in preparation of starch nanoparticles only affected opacity of films. The incorporation of nanoparticles in starch films resulted into denser films due to which the extent of variation of strain with temperature was much lower. The toughness and Young's modulus of films containing both types of starch nanoparticles were lower than those of control films especially at <100°C. PMID:23768605

Shi, Ai-Min; Wang, Li-Jun; Li, Dong; Adhikari, Benu



Impact of variety type and particle size distribution on starch enzymatic hydrolysis and functional properties of tef flours.  


Tef grain is becoming very attractive in the Western countries since it is a gluten-free grain with appreciated nutritional advantages. However there is little information of its functional properties and starch digestibility and how they are affected by variety type and particle size distribution. This work evaluates the effect of the grain variety and the mill used on tef flour physico-chemical and functional properties, mainly derived from starch behavior. In vitro starch digestibility of the flours by Englyst method was assessed. Two types of mills were used to obtain whole flours of different granulation. Rice and wheat flours were analyzed as references. Protein molecular weight distribution and flour structure by SEM were also analyzed to justify some of the differences found among the cereals studied. Tef cultivar and mill type exhibited important effect on granulation, bulking density and starch damage, affecting the processing performance of the flours and determining the hydration and pasting properties. The color was darker although one of the white varieties had a lightness near the reference flours. Different granulation of tef flour induced different in vitro starch digestibility. The disc attrition mill led to higher starch digestibility rate index and rapidly available glucose, probably as consequence of a higher damaged starch content. The results confirm the adequacy of tef flour as ingredient in the formulation of new cereal based foods and the importance of the variety and the mill on its functional properties. PMID:25439894

Abebe, Workineh; Collar, Concha; Ronda, Felicidad



Subcellular analysis of starch metabolism in developing barley seeds using a non-aqueous fractionation method.  


Compartmentation of metabolism in developing seeds is poorly understood due to the lack of data on metabolite distributions at the subcellular level. In this report, a non-aqueous fractionation method is described that allows subcellular concentrations of metabolites in developing barley endosperm to be calculated. (i) Analysis of subcellular volumes in developing endosperm using micrographs shows that plastids and cytosol occupy 50.5% and 49.9% of the total cell volume, respectively, while vacuoles and mitochondria can be neglected. (ii) By using non-aqueous fractionation, subcellular distribution between the cytosol and plastid of the levels of metabolites involved in sucrose degradation, starch synthesis, and respiration were determined. With the exception of ADP and AMP which were mainly located in the plastid, most other metabolites of carbon and energy metabolism were mainly located outside the plastid in the cytosolic compartment. (iii) In developing barley endosperm, the ultimate precursor of starch, ADPglucose (ADPGlc), was mainly located in the cytosol (80-90%), which was opposite to the situation in growing potato tubers where ADPGlc was almost exclusively located in the plastid (98%). This reflects the different subcellular distribution of ADPGlc pyrophosphorylase (AGPase) in these tissues. (iv) Cytosolic concentrations of ADPGlc were found to be close to the published K(m) values of AGPase and the ADPGlc/ADP transporter at the plastid envelope. Also the concentrations of the reaction partners glucose-1-phosphate, ATP, and inorganic pyrophosphate were close to the respective K(m) values of AGPase. (v) Knock-out of cytosolic AGPase in Riso16 mutants led to a strong decrease in ADPGlc level, in both the cytosol and plastid, whereas knock-down of the ADPGlc/ADP transporter led to a large shift in the intracellular distribution of ADPGlc. (v) The thermodynamic structure of the pathway of sucrose to starch was determined by calculating the mass-action ratios of all the steps in the pathway. The data show that AGPase is close to equilibrium, in both the cytosol and plastid, whereas the ADPGlc/ADP transporter is strongly displaced from equilibrium in vivo. This is in contrast to most other tissues, including leaves and potato tubers. (vi) Results indicate transport rather than synthesis of ADPGlc to be the major regulatory site of starch synthesis in barley endosperm. The reversibility of AGPase in the plastid has important implications for the regulation of carbon partitioning between different biosynthetic pathways. PMID:22200665

Tiessen, Axel; Nerlich, Annika; Faix, Benjamin; Hümmer, Christine; Fox, Simon; Trafford, Kay; Weber, Hans; Weschke, Winfriede; Geigenberger, Peter




Microsoft Academic Search

Biobased engineering materials from natural polymers such as potato starch and sisal fiber have increasingly attracted more attention compared with their petroleum counterparts due to biodegradability, environmental protection, and sustainable development. A novel biobased composite was developed based on phosphate crosslinked thermoplastic potato starch and sisal cellulose fiber aimed at improving mechanical properties and hydrophobicity.\\u000aFirst of all, potato starch

Gang Wang



Study on the stability of ?-carotene microencapsulated with pinhão (Araucaria angustifolia seeds) starch.  


Native and hydrolyzed pinhão starches were used as coating materials for ?-carotene microencapsulation by freeze-drying. The purpose of the present study was to evaluate the stability of ?-carotene encapsulated under three different conditions: in the presence of ultraviolet light at 25±2 °C, in the dark at 25±2 °C and in the dark at 10.0±0.2 °C. The color of the samples was also analyzed. Microcapsules prepared with native starch showed the lowest stability during storage. In contrast, microcapsules encapsulated with 12 dextrose equivalent (DE) hydrolyzed starch exhibited the highest stability. First-order kinetic and Weibull models were applied to describe the degradation of ?-carotene over time. The R(2) values of the Weibull model were greater than those of the first-order kinetic model. Moreover, multivariate analyses (principal component and cluster analyses) were also conducted. PMID:24750928

Spada, Jordana Corralo; Noreña, Caciano Pelayo Zapata; Marczak, Ligia Damasceno Ferreira; Tessaro, Isabel Cristina



Influence of maize genotype on rate of ruminal starch degradation  

E-print Network

itself, amylose or amylopectin, but also to the endosperm structure of the grain, and particularly" starch, a "normal" starch and an "extender" starch. The amylose : amylopectin ratios were determined

Paris-Sud XI, Université de


Structural and functional properties of C-type starches.  


This study investigated the structural and functional properties of C-type starches from pea seeds, faba bean seeds, yam rhizomes and water chestnut corms. These starches were mostly oval in shape with significantly different sizes and contents of amylose, damaged starch and phosphorus. Pea, faba bean and water chestnut starches had central hila, and yam starch had eccentric hilum. Water chestnut and yam starches had higher amylopectin short and long chain, respectively. Water chestnut and faba bean starches showed CA-type crystallinities, and pea and yam starches had C-type crystallinities. Water chestnut starch had the highest swelling power, granule swelling and pasting viscosity, lowest gelatinization temperatures and enthalpy. Faba bean starch had the lowest pasting viscosity, whereas yam starch had the highest gelatinization temperatures. Water chestnut and yam starches possessed significantly higher and lower susceptibility to acid and enzyme hydrolysis, the highest and lowest RDS contents, and the lowest and highest RS contents, respectively. PMID:24299776

Cai, Jinwen; Cai, Canhui; Man, Jianmin; Zhou, Weidong; Wei, Cunxu



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

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Issues of Starch in Sugarcane Processing and Prospects of Breeding for Low Starch Content in Sugarcane  

Technology Transfer Automated Retrieval System (TEKTRAN)

Starch is a sugarcane impurity that adversely affects the quantity and quality of sugar processes and products. The increased production of combine and green harvested sugarcane has increased delivery of starch to sugarcane factories. Starch occurs as granules composed of amylose and amylopectin p...


Position of modifying groups on starch chains of octenylsuccinic anhydride-modified waxy maize starch.  


Octenylsuccinic anhydride (OSA)-modified starches with a low (0.018) and high (0.092) degree of substitution (DS) were prepared from granular native waxy maize starch in aqueous slurry. The position of OS substituents along the starch chains was investigated by enzyme hydrolysis followed by chromatographic analysis. Native starch and two OS starches with a low and high DS had ?-limit values of 55.9%, 52.8%, and 34.4%, respectively. The weight-average molecular weight of the ?-limit dextrin from the OS starch with a low DS was close to that of the ?-limit dextrin from native starch but lower than that of the ?-limit dextrin from the OS starch with a high DS. Debranching of OS starches was incomplete compared with native starch. OS groups in the OS starch with a low DS were located on the repeat units near the branching points, whereas the OS substituents in the OS starch with a high DS occurred both near the branching points and the non-reducing ends. PMID:24491720

Bai, Yanjie; Kaufman, Rhett C; Wilson, Jeff D; Shi, Yong-Cheng



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

Technology Transfer Automated Retrieval System (TEKTRAN)

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 ...


Optical and thermal studies of starch/methylcellulose blends  

NASA Astrophysics Data System (ADS)

Starch and methylcellulose (MC) homopolymers and their blends were prepared using a casting technique. The samples were investigated by infrared (Fourier transform infrared (IR)), ultraviolet/visible (UV/VIS), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Significant changes in IR spectra of blend samples were observed, which indicated the occurrence of an intermolecular interactions between starch and MC. UV/VIS analyses revealed that the values of the optical band gap decreased with increasing MC content in blend samples. The positions of the investigated samples on the chromaticity diagram and the color parameters, such as L*, U*, V*, C*, hue and Ye, reflected the presence of a high color gradient and were composition dependent. A single glass transition temperature for each poly-blend sample was observed, which supported the existence of compatibility in such a system. The kinetic thermodynamic parameters, such as activation energy, enthalpy, entropy and Gibbs free energy, were evaluated from thermogravimetric analysis data using the Coats-Redfern relation.

Ragab, H. S.; Abd El-Kader, M. F. H.



Soil moisture and the infection of young potato tubers by Streptomyces scabies (common scab)  

Microsoft Academic Search

Majestic potatoes planted in soil naturally infested withStreptomyces scabies were trickle irrigated to prevent infection of the tubers except during consecutive 7-day periods in the first eight weeks when tubers were developing (28 May to 23 July).

D. H. Lapwood; T. F. Hering



Colorful Creatures  

NSDL National Science Digital Library

For animals, bright, flashy coloration can serve as a warning or as an invitation. Either way, colorful skin, feathers, and scales yell, Notice me! This collection of images shows examples of some of the world's most colorful creatures.

WGBH Educational Foundation



What is color for? Color  

E-print Network

What is color for? #12;#12;#12;#12;#12;#12;#12;#12;#12;Color · Physics ­ Light is E-M radiation of different frequencies. ­ Superposition principle · Perception ­ 3 cones -> 3D color space. (Metamers). ­ Convex subset of 3D linear space. ­ Color matching: can't represent w/ 3 primaries. · Color Spaces ­ CIE

Jacobs, David


In planta modification of the potato tuber cell wall  

Microsoft Academic Search

Apart from its well known uses in the human diet a large amount of the grown potatoes (about one third in the Netherlands) is used for the isolation of starch which is used in several food and non-food applications. The cell wall fibres comprise a large portion of the waste material remaining after the starch isolation process. While cell wall

R. J. F. J. Oomen



Starch columns: Analog model for basalt columns  

NASA Astrophysics Data System (ADS)

Desiccation of starch-water mixtures produces tensile-crack patterns which appear to be interesting, but largely unknown study objects for fracture mechanics, structural geology, and volcanology. This paper concentrates on columnar jointing and on columns in starch. Starch columns have polygonal cross sections and are very similar to basalt columns. They are produced by lamp drying starch specimens with dimensions of several centimeters and have diameters in the millimeter range. The columns develop behind a crack front which propagates from the surface into the interior. The experiments, supported by X ray tomograms, show that polygonal regularity of the crack pattern is not present at the surface but develops during penetration. This transition is steered by a minimum-fracture-energy principle. The analogy between basalt cooling and starch desiccation is far reaching: water concentration in starch is analogous to temperature in basalt, both quantities obey diffusion equations, water loss is equivalent to heat loss, the resulting contraction stresses have similar dependences on depth and time, and in both cases the material strength is exceeded. The starch experiments show that column diameters are controlled by the depth gradient of water concentration at the crack front. High (low) gradients are connected with thin (thick) columns. By analogy, a similar relation with the temperature gradient exists for basalt columns. The (normalized) starch gradients are about 3 orders of magnitude larger than the (normalized) gradients in basalt. This explains why starch columns are much thinner than basalt columns. The gradients are so different, because the crack front speeds differ by a factor of about 10: after 3 days the speed is about 10 mm/d in starch but about 100 mm/d in basalt [Peck, 1978]. The speed difference, in turn, results from the difference of the diffusion constants: the hydraulic diffusivity of starch is 2 orders of magnitude lower than the thermal diffusivity of basalt.

Müller, Gerhard




Technology Transfer Automated Retrieval System (TEKTRAN)

The development of a potato cultivar with increased calcium accumulation ability in the tuber is very important. Potato tuber tissue is known to be naturally deficient in calcium. Lack of adequate calcium is associated with tuber defects such as internal brown spot, hollow heart, and storage rot. We...


Effect of Different Genotypes of Phytophthora infestans (Mont. de Bary) and Temperature on Tuber  

E-print Network

Effect of Different Genotypes of Phytophthora infestans (Mont. de Bary) and Temperature on Tuber cultivars/Advance Breeding Lines (ABL) of potato with different genotypes of the potato late blight pathogen tuber resistance. The US-8 genotype isolates were the most aggressive in tubers in most years causing

Douches, David S.


Burial depth distribution of fennel pondweed tubers ( Potamogeton pectinatus) in relation to foraging by Bewick's swans  

Microsoft Academic Search

Deep burial in the sediment of tubers of fennel pondweed (Potamogeton pectinatus) has been explained in terms of avoidance by escape against consumption by Bewick's swans (Cygnus columbianus bewickii) in autumn. We therefore expected changes in foraging pressure to ultimately result in a change in the tuber distribution across sediment depth. A trade-off underlies this idea: deep tubers are less

Bert Hidding; Bart A. Nolet; Mennobart R. van Eerden; Matthieu Guillemain; Marcel Klaassen




Technology Transfer Automated Retrieval System (TEKTRAN)

Breeding strictly for foliar resistance to late blight without subsequent effort in tuber resistance has the potential to exacerbate tuber infection. Wild potato species can be valuable sources of foliar and tuber blight resistance. However, most species are difficult to sexually hybridize with cu...


Segregation of progeny of Solanum tuberosum subsp. andigena for foliar and tuber resistance to late blight.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Breeding solely for foliar resistance to late blight without emphasis on tuber resistance has the potential to exacerbate tuber infection. Wild potato species are valuable sources of foliar and tuber blight resistance. However, most species are difficult to sexually hybridize with cultivated potat...


Color realism and color science  

E-print Network

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, ...

Byrne, Alex


Ocatin. A Novel Tuber Storage Protein from the Andean Tuber Crop Oca with Antibacterial and Antifungal Activities1  

PubMed Central

The most abundant soluble tuber protein from the Andean crop oca (Oxalis tuberosa Mol.), named ocatin, has been purified and characterized. Ocatin accounts for 40% to 60% of the total soluble oca tuber proteins, has an apparent molecular mass of 18 kD and an isoelectric point of 4.8. This protein appears to be found only in tubers and is accumulated only within the cells of the pith and peridermis layers (peel) of the tuber as it develops. Ocatin inhibits the growth of several phytopathogenic bacteria (Agrobacterium tumefaciens, Agrobacterium radiobacter, Serratia marcescens, and Pseudomonas aureofaciens) and fungi (Phytophthora cinnamomi, Fusarium oxysporum, Rhizoctonia solani, and Nectria hematococcus). Ocatin displays substantial amino acid sequence similarity with a widely distributed group of intracellular pathogenesis-related proteins with a hitherto unknown biological function. Our results showed that ocatin serves as a storage protein, has antimicrobial properties, and belongs to the Betv 1/PR-10/MLP protein family. Our findings suggest that an ancient scaffolding protein was recruited in the oca tuber to serve a storage function and that proteins from the Betv 1/PR-10/MLP family might play a role in natural resistance to pathogens. PMID:11950978

Flores, Teresita; Alape-Girón, Alberto; Flores-Díaz, Marietta; Flores, Hector E.



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

PubMed Central

Two starch granule-bound proteins (SGP), SGP-140 and SGP-145, were preferentially associated with A-type starch granules (>10 ?m) 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 ?m) initiated before 15 DPA incorporated SGP-140 and SGP-145 throughout endosperm development and grew into full-size A-type starch granules (>10 ?m). 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 ?m). 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

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



Investigation of the tuber constituents of maca (Lepidium meyenii Walp.).  


Lepidium meyenii, known in South America as maca, has received attention worldwide as a powerful energizer that improves physical and mental conditions and increases fertility. Because of these reports, we investigated the secondary metabolites of the tuber of maca. The methanol extract of the tuber of maca contained, in addition to free sugars and amino acids, the following: uridine, malic acid and its benzoyl derivative, and the glucosinolates, glucotropaeolin and m-methoxyglucotropaeolin. Because glucosinolates and their derived products have received increasing attention due to their biological activities, the occurrence of glucosinolate degradation products in the hexane extract was also investigated, and benzylisothiocyanate and its m-methoxy derivative were isolated. The two glucosinolates were semiquantified by HPLC, and benzylisothiocyanate was semiquantified by GC/MS. The methanol extract of maca tuber also contained (1R,3S)-1-methyltetrahydro-beta-carboline-3-carboxylic acid, a molecule which is reported to exert many activities on the central nervous system. PMID:12236688

Piacente, Sonia; Carbone, Virginia; Plaza, Alberto; Zampelli, Aurelia; Pizza, Cosimo



Renal Hamartoma (Angiomyolipoma) and the Tuberous Sclerosis Complex  

PubMed Central

Renal hamartoma is found in 40 to 80 percent of patients with tuberous sclerosis. Microscopic demonstration of fat in the tissues of the mass is felt to be the most reliable diagnostic criterion of hamartoma. Characteristically, the angiographic appearance demonstrates a large, dilated feeding vessel passing through the mass with multiple, multisacculated aneurysmal dilatations appearing like bunches of grapes. There is a delicate neovascularity without A-V shunting and an onion-peel or whorl-like appearance in the venous phase. This case is presented to point out the close association of renal hamartoma and tuberous sclerosis and the need to search for renal hamartoma when the diagnosis of tuberous sclerosis is made. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:423276

Pacis, Andresito B.; Norman, Calvin H.



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


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. PMID:25529655

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



Renal cell carcinoma in tuberous sclerosis complex.  


Renal cell carcinoma (RCC) occurs in 2% to 4% of patients with tuberous sclerosis complex (TSC). Previous reports have noted a variety of histologic appearances in these cancers, but the full spectrum of morphologic and molecular features has not been fully elucidated. We encountered 46 renal epithelial neoplasms from 19 TSC patients and analyzed their clinical, pathologic, and molecular features, enabling separation of these 46 tumors into 3 groups. The largest subset of tumors (n=24) had a distinct morphologic, immunologic, and molecular profile, including prominent papillary architecture and uniformly deficient succinate dehydrogenase subunit B (SDHB) expression prompting the novel term "TSC-associated papillary RCC (PRCC)." The second group (n=15) were morphologically similar to a hybrid oncocytic/chromophobe tumor (HOCT), whereas the last 7 renal epithelial neoplasms of group 3 remained unclassifiable. The TSC-associated PRCCs had prominent papillary architecture lined by clear cells with delicate eosinophilic cytoplasmic thread-like strands that occasionally appeared more prominent and aggregated to form eosinophilic globules. All 24 (100%) of these tumors were International Society of Urological Pathology (ISUP) nucleolar grade 2 or 3 with mostly basally located nuclei. Tumor cells from 17 of 24 TSC-associated PRCCs showed strong, diffuse labeling for carbonic anhydrase IX (100%), CK7 (94%), vimentin (88%), and CD10 (83%) and were uniformly negative for SDHB, TFE3, and AMACR. Gains of chromosomes 7 and 17 were found in 2 tumors, whereas chromosome 3p deletion and TFE3 translocations were not detected. In this study, we reported a sizable cohort of renal tumors seen in TSC and were able to identify them as different morphotypes, which may help to expand the morphologic spectrum of TSC-associated RCC. PMID:24832166

Yang, Ping; Cornejo, Kristine M; Sadow, Peter M; Cheng, Liang; Wang, Mingsheng; Xiao, Yu; Jiang, Zhong; Oliva, Esther; Jozwiak, Sergiusz; Nussbaum, Robert L; Feldman, Adam S; Paul, Elahna; Thiele, Elizabeth A; Yu, Jane J; Henske, Elizabeth P; Kwiatkowski, David J; Young, Robert H; Wu, Chin-Lee



Production of PLA-Starch Fibers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Composites of polylactic acid (PLA) with starch have been prepared previously in an effort to reduce cost as well as to modify other properties such as biodegradation rate. However, strength and elongation both decrease on addition of starch due to poor adhesion and stress concentration at the inte...


Getting the Starch Out of Your Food  

NSDL National Science Digital Library

In this activity, learners examine the amount of starch in different foods. Learners use iodine to perform a simple test on food samples like apples and potatoes to see which foods contain starch and how much. Adult supervision is recommended. This activity page features an animation of this experiment (shockwave required).

California Science Center




Technology Transfer Automated Retrieval System (TEKTRAN)

The viscosity and gel formation in the tricomponent system, starch/poly(acrylic acid)/poly(vinyl pyrrolidone-iodine), are studied in this work. Starch and poly(acrylic acid) at 5% aqueous solution form a synergistic mixture at 60/40 ratio. The addition of a small amount of poly(vinyl pyrrolidone)-...


Friction Properties of Chemically Modified Starch  

Technology Transfer Automated Retrieval System (TEKTRAN)

Starch is a high molecular weight polyglucose biopolymer that, in its native state, is insoluble in water at room temperature. One way of improving its water solubility is by esterification of its free hydroxyl groups. Waxy maize, normal corn, and high amylose corn starches were esterified with ac...


Colorful Chemistry.  

ERIC Educational Resources Information Center

Described is an color-making activity where students use food coloring, eyedroppers, and water to make various colored solutions. Included are the needed materials and procedures. Students are asked to write up the formulas for making their favorite color. (KR)

Williams, Suzanne



Color Addition  

NSDL National Science Digital Library

This activity is inquiry in that students do not know how colors are combined. They likely think that the primary colors are red, yellow, and blue. In fact, there are two sets of primary colors: red, green, and blue for additive colors of light, and cyan,

Michael Horton



Color Mixing  

NSDL National Science Digital Library

This is an online activity where learners can virtually mix different colors of light or paint (you can switch between them) and see how the colors combine. It demonstrates how millions of colors are created on computer monitors and TVs, and in art and printing. Learners can try to match a given target color ("Mix to Match"), or simply play around with mixtures ("Mix for Fun"). Background information explains how light is additive (more colors tends towards white), whereas paint absorbs color and is subtractive (more colors tends towards black). There's also information about how the human eye works.

Oregon Museum of Science and Industry



Barley grain constituents, starch composition, and structure affect starch in vitro enzymatic hydrolysis.  


The relationship between starch physical properties and enzymatic hydrolysis was determined using ten different hulless barley genotypes with variable carbohydrate composition. The ten barley genotypes included one normal starch (CDC McGwire), three increased amylose starches (SH99250, SH99073, and SB94893), and six waxy starches (CDC Alamo, CDC Fibar, CDC Candle, Waxy Betzes, CDC Rattan, and SB94912). Total starch concentration positively influenced thousand grain weight (TGW) (r(2) = 0.70, p < 0.05). Increase in grain protein concentration was not only related to total starch concentration (r(2) = -0.80, p < 0.01) but also affected enzymatic hydrolysis of pure starch (r(2) = -0.67, p < 0.01). However, an increase in amylopectin unit chain length between DP 12-18 (F-II) was detrimental to starch concentration (r(2) = 0.46, p < 0.01). Amylose concentration influenced granule size distribution with increased amylose genotypes showing highly reduced volume percentage of very small C-granules (<5 ?m diameter) and significantly increased (r(2) = 0.83, p < 0.01) medium sized B granules (5-15 ?m diameter). Amylose affected smaller (F-I) and larger (F-III) amylopectin chains in opposite ways. Increased amylose concentration positively influenced the F-III (DP 19-36) fraction of longer DP amylopectin chains (DP 19-36) which was associated with resistant starch (RS) in meal and pure starch samples. The rate of starch hydrolysis was high in pure starch samples as compared to meal samples. Enzymatic hydrolysis rate both in meal and pure starch samples followed the order waxy > normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed a higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased ?-glucan and dietary fiber concentration also reduced the enzymatic hydrolysis of meal samples. An average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p < 0.01) influenced resistant starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 ?m) and the amylopectin F-III (19-36 DP) fraction. In conclusion, the results suggest that barley genotype SH99250 with less decrease in grain weight in comparison to that of other increased amylose genotypes (SH99073 and SH94893) could be a promising genotype to develop cultivars with increased amylose grain starch without compromising grain weight and yield. PMID:21462932

Asare, Eric K; Jaiswal, Sarita; Maley, Jason; Båga, Monica; Sammynaiken, Ramaswami; Rossnagel, Brian G; Chibbar, Ravindra N




E-print Network

. Se detennin6 visualmente el color de la papa 'Asst. Prof. and former Ph.D. student, Dept. of Crop and Soil Sciences. Michigan State Univ.. East LanSlllg, MI 48824. Prese nt addre~s of ur. f, eyre i$ Dept (II). The reduc ing sug'ar levels in potato tubers is the primary f

Douches, David S.


Different color Same color Similarityrating  

E-print Network

1 2 3 4 5 6 7 8 9 Different color Same color Similarityrating Object pair A central principle color localizer. Feature diagnosticity affects semantic representations of novel and common object. blobby 3. round 4. Using color as the diagnostic feature, we used a training paradigm to investigate how

Thompson-Schill, Sharon


Adsorption of Polyethylene from Solution onto Starch Film Surfaces  

Technology Transfer Automated Retrieval System (TEKTRAN)

Since starch adsorbs onto polyethylene (PE) surfaces from cooled solutions of jet cooked starch, this study was carried out to determine whether adsorption of PE onto hydrophilic starch film surfaces would also take place if starch films were placed in hot solutions of PE in organic solvents, and th...



Technology Transfer Automated Retrieval System (TEKTRAN)

Endosperm starch and pericarp starch were isolated from maize (B73) kernels at different developmental stages. Starch granules, with small size (2-4 'm diameter), were first observed in the endosperm on 5 days after pollination (DAP). The size of endosperm-starch granules remained similar until 12DA...


Root zone calcium can modulate GA induced tuberization signal  

Technology Transfer Automated Retrieval System (TEKTRAN)

The present study was conducted to investigate the possible relationship between root zone calcium and GA3 concentration in tuberization signal. For this purpose, we developed a system utilizing in vitro propagated potato plantlets and pure silica sand that allows precise control of root zone chemic...


Endometrial Adenocarcinoma Presenting in a Premenopausal Patient with Tuberous Sclerosis  

ERIC Educational Resources Information Center

Background: Endometrial adenocarcinoma is very uncommon in women under 40 years of age. Case: A 39-year-old woman with tuberous sclerosis and severe intellectual disability presented with irregular bleeding unresponsive to oral contraceptive therapy. She was subsequently found to have a deeply invasive endometrial adenocarcinoma. Conclusion:…

Jaffe, J. S.; Chambers, J. T.



Rapamycin causes regression of astrocytomas in tuberous sclerosis complex  

Microsoft Academic Search

Objective: Tuberous sclerosis complex (TSC) is a genetic disorder characterized by the formation of hamartomas in multiple organs. Five to 15% of affected individuals display subependymal giant cell astrocytomas, which can lead to substantial neurological and postoperative morbidity due to the production of hydrocephalus, mass effect, and their typical location adjacent to the foramen of Monro. We sought to see

David Neal Franz; Jennifer Leonard; Cynthia Tudor; Gail Chuck; Marguerite Care; Gopalan Sethuraman; Argirios Dinopoulos; George Thomas; Kerry R. Crone



Halosulfuron reduces purple nutsedge (Cyperus rotundus) tuber production and viability  

Technology Transfer Automated Retrieval System (TEKTRAN)

Purple nutsedge is one of the most troublesome weeds of fresh-market vegetable crops in the Southern U.S. A perennial weed, purple nutsedge reproduces vegetatively by producing chains of tubers. Halosulfuron is an effective means of controlling purple nutsedge foliage and is registered for use in ...


Gene Expression Associated with Tuber Wound-Healing/Suberization  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wounding of potatoes during harvest and handling operations results in tuber shrinkage, market quality defects and infection. Suberization and other wound-healing processes that mitigate these losses are of great agricultural importance. Previously, we determined that suberin poly(phenolics) and s...



Technology Transfer Automated Retrieval System (TEKTRAN)

Management of volunteer potato requires an integrated approach and soil fumigation is one tactic known to reduce population densities of certain weeds. The effect of 1,3-D and metham sodium on potato tuber viability were tested in sealed glass jars at various doses, incubation temperatures, and tim...


Regulatory involvement of ABA in potato tuber wound-healing  

Technology Transfer Automated Retrieval System (TEKTRAN)

Rapid wound-healing is crucial in protecting potato tubers from infection and dehydration. Wound-induced suberization and the accumulation of hydrophobic barriers to reduce water vapor conductance/loss are principle protective wound-healing processes. However, little is known about the biological ...



Technology Transfer Automated Retrieval System (TEKTRAN)

The ion chromatographic method for the quantification of phytate (InsP6) in foods was adapted for the analysis of roots and tubers. To maximize sensitivity, UV detection following post-column derivatization was compared with evaporative light scattering detection (ELSD). Detection limits for phyta...


Potato spindle tuber viroid: the simplicity paradox resolved?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Taxonomy: Potato spindle tuber viroid (PSTVd) is the type species of the genus Posipiviroid, family Pospiviroidae. An absence of hammerhead ribozymes and the presence of a 'central conserved region' distinguish PSTVd and related viroids from members of a second viroid family, the Avsunviroidae. ...


Halosulfuron reduced purple netsedge (Cyperus rotundus) tuber production and viability  

Technology Transfer Automated Retrieval System (TEKTRAN)

Weeds persist and cause economic losses in agricultural systems because they exploit an underutilized portion of that system. Reducing the impact of weeds on agroecosystems begins with minimizing the number of propagules (e.g, seeds and tubers) that are produced and returned to the soil. Purple nu...


Genetics and Molecular Biology of Tuberous Sclerosis Complex  

PubMed Central

Tuberous Sclerosis Complex is a multisystem disorder exhibiting a wide range of manifestations characterized by tumour-like lesions called hamartomas in the brain, skin, eyes, heart, lungs and kidneys. Tuberous Sclerosis Complex is genetically determined with an autosomal dominant inheritance and is caused by inactivating mutations in either the TSC1 or TSC2 genes. TSC1/2 genes play a fundamental role in the regulation of phosphoinositide 3-kinase (PI3K) signalling pathway, inhibiting the mammalian target of rapamycin (mTOR) through activation of the GTPase activity of Rheb. Mutations in TSC1/2 genes impair the inhibitory function of the hamartin/tuberin complex, leading to phosphorylation of the downstream effectors of mTOR, p70 S6 kinase (S6K), ribosomal protein S6 and the elongation factor binding protein 4E-BP1, resulting in uncontrolled cell growth and tumourigenesis. Despite recent promising genetic, diagnostic, and therapeutic advances in Tuberous Sclerosis Complex, continuing research in all aspects of this complex disease will be pivotal to decrease its associated morbidity and mortality. In this review we will discuss and analyse all the important findings in the molecular pathogenesis of Tuberous Sclerosis Complex, focusing on genetics and the molecular mechanisms that define this multisystemic disorder. PMID:19506736

Napolioni, Valerio; Curatolo, Paolo



Directional sensitivity of tuberous electroreceptors: polarity preferences and frequency tuning  

Microsoft Academic Search

This paper examines the directionality of tuberous electroreceptor responses and relates them to a polarity bias seen for passive electrolocation by electric fish (Hypopomus). We recorded from Burst Duration Coders (BDCs) while stimulating with 1 kHz single period sine waves with electric fields oriented horizontally in different directions. Electroreceptors have figure-8 directional sensitivity profiles with two, usually unequal lobes of

J. R. McKibben; C. D. Hopkins; D. D. Yager




Technology Transfer Automated Retrieval System (TEKTRAN)

Potato tuber moth (PTM) is a serious pest of stored potato in most countries where potatoes are grown. Pathogens that are specific to insects offer promise as alternatives to broad spectrum insecticides for management of this pest. A diverse spectrum of microscopic and multicellular organisms (bact...


Proteins interacting with the tuberous sclerosis gene products  

Microsoft Academic Search

Summary. Tuberous sclerosis (TSC) is an autosomal dominant tumor suppressor gene syndrome affecting about 1 in 6000 to 10000 individuals. The genes, TSC1, encoding hamartin, and TSC2, encoding tuberin are responsible for TSC. Since their identification 1997 and 1993 respectively, a variety of different functions have been described for the TSC gene products. Hamartin and tuberin form a complex, providing

M. Rosner; A. Freilinger; M. Hengstschläger



Tuberous sclerosis: diffusion MRI findings in the brain.  


Diffusion MRI has mainly been used for detection of acute ischemia, and for distinction of cytotoxic and vasogenic edema. We applied diffusion MRI in patients with tuberous sclerosis in order to evaluate diffusion imaging characteristics of parenchymal changes. Five children with known tuberous sclerosis were included in this study. The MRI examinations were performed on a 1.5-T MR unit. Diffusion MRI was obtained using the echo-planar imaging sequence. Apparent diffusion coefficient (ADC) values from the abnormal brain parenchyma were calculated directly from automatically generated ADC maps. Seven normal children were available for comparison. In this control group the mean ADC value of the normal white matter was 0.84 +/- 0.12 x 10(-3) mm(2)/s. In tuberous sclerosis patients the mean ADC value of the white matter hamartomas ( n=20) was apparently high (1.52 +/- 0.24 x 10(-3) mm(2)/s) compared with that of normal white matter. The ADC value of calcified hamartomas was "zero". The ADC value within a giant cell tumor was 0.89 x 10(-3) mm(2)/s, similar to that of normal cerebral white matter. The ADC maps were superior to b=1000 s/mm(2) (true diffusion) images with respect to lesion evaluation, and they provided mathematical information on tissue integrity. With respect to detection of the exact numbers and sizes of the parenchymal hamartomas fluid-attenuated inversion recovery images were superior to ADC maps. It is believed that diffusion MRI can be useful in evaluation of various parenchymal changes associated with tuberous sclerosis. Further studies on tuberous sclerosis, and on various brain lesions, would provide increasing data on this relatively new MRI sequence. PMID:11868090

Sener, R N



Firming of Bread Crumb with Cross-Linked Waxy Barley Starch Substituted for Wheat Starch  

Microsoft Academic Search

Cereal Chem. 69(3):321-325 White pan bread was baked from flour that had been fractionated a higher enthalpy of melting than that of control bread crumb, except and reconstituted using cross-linked waxy barley starch (5.9% amylose at 6 hr after baking. Furthermore, a 50% gel of cross-linked waxy barley content) in place of prime wheat starch (28.3% amylose content). starch in




Preparation of metallic nanoparticles by irradiation in starch aqueous solution  

NASA Astrophysics Data System (ADS)

Colloidal silver nanoparticles (AgNPs) were synthesized in a single step by electron beam irradiation reduction of silver ions in aqueous solution containing starch. The nanoparticles were characterized by spectrophotocolorimetry and compared with those obtained by chemical (thermal) reduction method. The results showed that the smaller sizes of AgNPs were prepared with higher yields as the irradiation dose increased. The broadening of particle size distribution occurred by increasing of irradiation dose and dose rate. Chromatic parameters such as b* (yellow-blue coordinate), C* (chroma) and ?Eab (total color difference) could characterize the nanoparticles with respect of their concentration. Hue angle ho was correlated to the particle size distribution. Experimental data of the irradiated samples were also subjected to factor analysis using principal component extraction and varimax rotation in order to reveal the relation between dependent variables and independent variables and to reduce their number. The radiation-based method provided silver nanoparticles with higher concentration and narrower size distribution than those produced by chemical reduction method. Therefore, the electron beam irradiation is effective for preparation of silver nanoparticles using starch aqueous solution as dispersion medium.

Nemţanu, Monica R.; Bra?oveanu, Mirela; Iacob, Nicu?or



Psychopathology in Tuberous Sclerosis: An Overview and Findings in a Population-Based Sample of Adults with Tuberous Sclerosis  

ERIC Educational Resources Information Center

Background: Tuberous sclerosis (TS) is a multi- system disorder with complex genetics. The neurodevelopmental manifestations of TS are responsible for considerable morbidity. The prevalence of epilepsy and intellectual disabilities among individuals with TS have been well described. Ours is the first study that explores the prevalence and pattern…

Raznahan, A.; Joinson, C.; O'Callaghan, F.; Osborne, J. P.; Bolton, P. F.



The Effect of Vine Kill and Harvest Date on Tuber Skin Set, Respiration Rates and Tuber Sugars  

Technology Transfer Automated Retrieval System (TEKTRAN)

Russet Burbank potatoes were grown using standard procedures for planting, fertilization, irrigation, and pest management. Vine kill and harvest occurred on three staggered dates that spanned approximately six weeks. Vines were either killed chemically or left untreated and tubers were harvested fro...


Electron microscopy and composition of raw acorn starch in relation to in vivo starch digestibility.  


The structure and composition of starch play an important role as co-factors affecting raw starch digestibility: such features were investigated in raw acorn starch from the most diffused oak trees in the Mediterranean basin. A total of 620 whole ripe acorns from Holm (Quercus ilex L., n = 198), Downy (Quercus pubescens Willd., n = 207) and Cork (Quercus suber L., n = 215) oaks sampled on the Sardinia Isle (40° 56' 0'' N; 9° 4' 0'' E; 545 m above the mean sea level) in the same geographical area, were analyzed for their chemical composition. The starch contents ranged between 51.2% and 53.5% of dry matter. The starch granules displayed a spheroid/ovoid and cylindrical shape; on scanning electron microscopic (SEM) analyses, a bimodal distribution of starch granule size was observed both for Holm and Cork oak acorns, whereas the starch granules of Downy oak acorns showed diameters between 10.2 and 13.8 ?m. The specific amylose to amylopectin ratio of acorn starch was 25.8%, 19.5% and 34.0% in the Holm, Downy and Cork oaks, respectively. The (13)C Nuclear Magnetic Resonance (NMR) signal analysis displayed a pivotal spectrum for the identification of the amylose peaks in raw acorn starch, as a basis for the amylose to amylopectin ratio determination. PMID:23660700

Cappai, Maria Grazia; Alesso, Giuseppe Andrea; Nieddu, Giuseppa; Sanna, Marina; Pinna, Walter



Color notations  

E-print Network

This study presents research regarding the language of colors and of computers. The focus was color: translated through personal imagery, transferred and changed through media, and programmed through the computer. The ...

Gardner, Nancy



Association of Starch Granule Proteins with Starch Ghosts and Remnants Revealed by Confocal Laser Scanning Microscopy 1  

Microsoft Academic Search

Cereal Chem. 79(6):892-896 Starch suspensions (0.25%) were gelatinized to 70 and 100 C, and starch ghosts (defined as gelatinized starch granule envelopes after the majority of internal starch polymers have been released) and remnants were collected by centrifugation and washed with water. Protein was revealed in isolated gelatinized normal starch ghosts using confocal laser scanning microscopy and a protein-specific dye

Xian-Zhong Han; Bruce R. Hamaker



Genetic elimination of a starch granule protein, SGP1, of wheat generates an altered starch with apparent high amylose  

Microsoft Academic Search

A starch granule protein, SGP-1, is a starch synthase bound to starch granules in wheat endosperm. A wheat lacking SGP-1 was\\u000a produced by crossing three variants each deficient in one of three SGP-1 classes, namely SGP-A1, -B1 or -D1. This deficient\\u000a wheat (SGP–1 null wheat) showed some alterations in endosperm starch, meaning that SGP-1 is involved in starch synthesis.\\u000a Electrophoretic

M. Yamamori; S. Fujita; K. Hayakawa; J. Matsuki; T. Yasui



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


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 65.9g 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. PMID:25842330

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



Potential aromatic compounds as markers to differentiate between Tuber melanosporum and Tuber indicum truffles.  


The Tuber indicum (Chinese truffle) and Tuber melanosporum (Black truffle) species are morphologically very similar but their aromas are very different. The black truffle aroma is much more intense and complex, and it is consequently appreciated more gastronomically. This work tries to determine whether the differences between the aromatic compounds of both species are sufficiently significant so as to apply them to fraud detection. An olfactometric evaluation (GC-O) of T. indicum was carried out for the first time. Eight important odorants were identified. In order of aromatic significance, these were: 1-octen-3-one and 1-octen-3-ol, followed by two ethyl esters (ethyl isobutyrate and ethyl 2-methylbutyrate), 3-methyl-1-butanol, isopropyl acetate, and finally the two sulfides dimethyldisulfide (DMDS) and dimethylsulfide (DMS). A comparison of this aromatic profile with that of T. melanosporum revealed the following differences: T. indicum stood out for the significant aromatic contribution of 1-octen-3-one and 1-octen-3-ol (with modified frequencies (MF%) of 82% and 69%, respectively), while in the case of T. melanosporum both had modified frequencies of less than 30%. Ethyl isobutyrate, ethyl 2-methylbutyrate and isopropyl acetate were also significantly higher, while DMS and DMDS had low MF (30-40%) compared to T. melanosporum (>70%). The volatile profiles of both species were also studied by means of headspace solid-phase microextraction (HS-SPME-GC-MS). This showed that the family of C8 compounds (3-octanone, octanal, 1-octen-3-one, 3-octanol and 1-octen-3-ol) is present in T. indicum at much higher levels. The presence of 1-octen-3-ol was higher by a factor of about 100, while 1-octen-3-one was detected in T. indicum only (there was no chromatographic signal in T. melanosporum). As well as showing the greatest chromatographic differences, these two compounds were also the most powerful from the aromatic viewpoint in the T. indicum olfactometry. Therefore, either of the two chromatographic methods (GC-O or HS-SPME-GC-MS), together or separately, could be used as a screening technique to distinguish between T. indicum and T. melanosporum and thus avoid possible fraud. PMID:23768334

Culleré, Laura; Ferreira, Vicente; Venturini, María E; Marco, Pedro; Blanco, Domingo



Seeing Color  

ERIC Educational Resources Information Center

Colors are powerful tools for engaging children, from the youngest years onward. We hang brightly patterned mobiles above their cribs and help them learn the names of colors as they begin to record their own ideas in pictures and words. Colors can also open the door to an invisible world of electromagnetism, even when children can barely imagine…

Texley, Juliana



Increased soil salinity causes elevated cadmium concentrations in field-grown potato tubers  

SciTech Connect

Elevated Cd concentrations have been observed in potato (Solanum tuberosum L.) tubers from commercial crops in certain regions of southern Australia. Reasons for enhanced Cd uptake by tubers were investigated by a survey of commercial crops and associated soils. Eighty-nine sites were selected and paired tuber and soil samples taken. Concentration of Cd in tubers was compared to potato variety, tuber elemental composition, and chemical-physical characteristics of topsoil (0-150) and subsoil (150-300 mm). Tuber Cd concentrations were positively related to soil electrical conductivity (EC) and extractable Cl (R{sup 2} = 0.62, P < 0.001) in the topsoil, with extractable Cl accounting for more variation than EC. Tuber Cd concentrations were not strongly related (R{sup 2} = 0.23, P < 0.05) to potato variety alone. However, inclusion of variety and EDTA-extractable Zn with water-extractable Cl in a multivariate model resulted in a small but significant improvement in the variance accounted for by the model (R{sup 2} = 0.73, p < 0.001). Tuber Cd was unrelated to tuber concentrations of P or tuber but was positively related to concentrations of major cations in the tuber particularly Na. Soil pH, total C, EDTA-extractable Cd, or particle-size distribution were not correlated to tuber Cd concentrations, either singly or after inclusion in a multivariate model with soil Cl concentrations. As Cl is known to mobilize soil Cd and increase its phytoavailability, elevated Cd concentrations in potato tubers in southern Australia appear to be largely a result of the use of saline irrigation waters. 41 refs., 5 figs., 4 tabs.

McLaughlin, M.J.; Tiller, K.G.; Beech, T.A. [CSIRO Div. of Soils, Glen Osmond (Australia)] [and others



Synthesis of silver nanoparticles using Dioscorea bulbifera tuber extract and evaluation of its synergistic potential in combination with antimicrobial agents  

PubMed Central

Background Development of an environmentally benign process for the synthesis of silver nanomaterials is an important aspect of current nanotechnology research. Among the 600 species of the genus Dioscorea, Dioscorea bulbifera has profound therapeutic applications due to its unique phytochemistry. In this paper, we report on the rapid synthesis of silver nanoparticles by reduction of aqueous Ag+ ions using D. bulbifera tuber extract. Methods and results Phytochemical analysis revealed that D. bulbifera tuber extract is rich in flavonoid, phenolics, reducing sugars, starch, diosgenin, ascorbic acid, and citric acid. The biosynthesis process was quite fast, and silver nanoparticles were formed within 5 hours. Ultraviolet-visible absorption spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, energy dispersive spectroscopy, and x-ray diffraction confirmed reduction of the Ag+ ions. Varied morphology of the bioreduced silver nanoparticles included spheres, triangles, and hexagons. Optimization studies revealed that the maximum rate of synthesis could be achieved with 0.7 mM AgNO3 solution at 50°C in 5 hours. The resulting silver nanoparticles were found to possess potent antibacterial activity against both Gram-negative and Gram-positive bacteria. Beta-lactam (piperacillin) and macrolide (eryth-romycin) antibiotics showed a 3.6-fold and 3-fold increase, respectively, in combination with silver nanoparticles selectively against multidrug-resistant Acinetobacter baumannii. Notable synergy was seen between silver nanoparticles and chloramphenicol or vancomycin against Pseudomonas aeruginosa, and was supported by a 4.9-fold and 4.2-fold increase in zone diameter, respectively. Similarly, we found a maximum 11.8-fold increase in zone diameter of streptomycin when combined with silver nanoparticles against E. coli, providing strong evidence for the synergistic action of a combination of antibiotics and silver nanoparticles. Conclusion This is the first report on the synthesis of silver nanoparticles using D. bulbifera tuber extract followed by an estimation of its synergistic potential for enhancement of the antibacterial activity of broad spectrum antimicrobial agents. PMID:22334779

Ghosh, Sougata; Patil, Sumersing; Ahire, Mehul; Kitture, Rohini; Kale, Sangeeta; Pardesi, Karishma; Cameotra, Swaranjit S; Bellare, Jayesh; Dhavale, Dilip D; Jabgunde, Amit; Chopade, Balu A



Starch Phosphorylase Inhibitor Is ?-Amylase 1  

PubMed Central

The proteinaceous noncompetitive inhibitor of starch phosphorylase isolated from the root of sweet potato (Ipomoea batatas [L.] Lam.) (TC Chang, JC Su 1986 Plant Physiol 80: 534-538) has been identified as a ?-amylase. The starch phosphorylase inhibitor and ?-amylase activities copurified to give a protein indistinguishable from commercial ?-amylase by electrophoretic and immunological methods, and the two activities showed parallel responses in pH, temperature, and inhibitor sensitivity tests. The amylolytic pattern of the inhibitor corresponded to that of ?-amylase and its inhibitory effect toward starch phosphorylase was due to neither deprivation of starch, the primer for the phosphorylase assay, nor the inhibitory effect of amylolytic products. Images Fig. 2 Fig. 3 PMID:16666436

Pan, Shu-Mei; Chang, Tsung-Chain; Juang, Rong-Huay; Su, Jong-Ching



Starch-Poly(Hydroxylalkanoate) Composites and Blends  

Technology Transfer Automated Retrieval System (TEKTRAN)

This paper summarizes research on starch-polyhydroxyalkanoate (PHA) blends and composites. Efforts to increase compatibility, characterize mechanical and biodegradation properties are described. A range of blend products have been prepared including molded plastics, films and foams. Finally, futu...


[Characterisation of Dioscorea bulbifera native starch].  


A non conventional source of starch, bulbs of Dioscorea bulbifera, was evaluated. Giving a yield of 28.48 g/100 g on dry weight, chemical composition, physical, physico-chemical and morphological characteristics were assessed, as well as its rheological properties. Chemical analysis showed a amylose content of 29.37%. Micrographies showed that most of the starch granules were of irregular shape, similar to a pyramid with rounded vertices, and a smaller number were elongated with smooth surface. Dioscorea starch showed a gelatinization temperature of 70.8 degrees C and maximum viscosity at 88.6 degrees C of 435 Brabender units (BU). It presented a relatively stable consistency to the cooking process and a low tendency to retrogradation; which suggest the starch possible use in food products that need a fast viscosity and a gel with a stable consistency. PMID:15586695

Araujo de Vizcarrondo, Consuelo; Rincón, Alicia Mariela; Padilla, Fanny



Production of modified starches by gamma irradiation  

NASA Astrophysics Data System (ADS)

As a new processing method for the production of modified starch, gamma irradiation and four kinds of inorganic peroxides were applied to commercial corn starch. The addition of inorganic peroxides without gamma irradiation or gamma irradiation without the addition of inorganic peroxides effectively decreased initial viscosity, but did not sufficiently keep viscosity stable. The combination of adding ammonium persulfate (APS) and gamma irradiation showed the lowest initial viscosity and the best stability out of the tested four kinds of inorganic peroxides. Among the tested mixing methods of APS, soaking was found to be more effective than dry blending or spraying. Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability became feasible by the control of gamma irradiation dose levels and the amount of added APS to starch.

Kang, Il-Jun; Byun, Myung-Woo; Yook, Hong-Sun; Bae, Chun-Ho; Lee, Hyun-Soo; Kwon, Joong-Ho; Chung, Cha-Kwon



Rheological behaviour of heated potato starch dispersions  

NASA Astrophysics Data System (ADS)

The study was designed to investigate the rheological properties of heated potato starch dispersions. Water suspensions of starch were heated at 65, 80 or 95°C for 5, 15, 30 or 60 min. The dispersions obtained were examined for granule size distribution and rheology. It was found that the starch dispersions significantly differed in both respects. The mean diameters of starch granules were largest for the dispersion heated at 65°C and smallest for that heated at 95°C. As the heating temperature was raised, the yield stresses and consistency coefficients decreased, while the flow behaviour indexes and Casson plastic viscosities increased. There were also differences in the viscoelastic properties of the dispersions: for those heated at 65°C the storage and loss moduli increased with heating time whereas for those heated at 80°C both moduli decreased.

Juszczak, L.; Witczak, M.; Ziêba, T.; Fortuna, T.



Starch Synthesis in Arabidopsis Is Achieved by Spatial Cotranscription of Core Starch Metabolism Genes1[W][OA  

PubMed Central

Starch synthesis and degradation require the participation of many enzymes, occur in both photosynthetic and nonphotosynthetic tissues, and are subject to environmental and developmental regulation. We examine the distribution of starch in vegetative tissues of Arabidopsis (Arabidopsis thaliana) and the expression of genes encoding core enzymes for starch synthesis. Starch is accumulated in plastids of epidermal, mesophyll, vascular, and root cap cells but not in root proper cells. We also identify cells that can synthesize starch heterotrophically in albino mutants. Starch synthesis in leaves is regulated by developmental stage and light. Expression of gene promoter-?-glucuronidase fusion constructs in transgenic seedlings shows that starch synthesis genes are transcriptionally active in cells with starch synthesis and are inactive in root proper cells except the plastidial phosphoglucose isomerase. In addition, ADG2 (for ADPG PYROPHOSPHORYLASE2) is not required for starch synthesis in root cap cells. Expression profile analysis reveals that starch metabolism genes can be clustered into two sets based on their tissue-specific expression patterns. Starch distribution and expression pattern of core starch synthesis genes are common in Arabidopsis and rice (Oryza sativa), suggesting that the regulatory mechanism for starch metabolism genes may be conserved evolutionarily. We conclude that starch synthesis in Arabidopsis is achieved by spatial coexpression of core starch metabolism genes regulated by their promoter activities and is fine-tuned by cell-specific endogenous and environmental controls. PMID:19759345

Tsai, Huang-Lung; Lue, Wei-Ling; Lu, Kuan-Jen; Hsieh, Ming-Hsiun; Wang, Shue-Mei; Chen, Jychian



Structure and Functionality of Barley Starches  

Microsoft Academic Search

Cereal Chem. 75(5):747-754 Amylose contents of prime starches from nonwaxy and high-amylose barley, determined by colorimetric method, were 24.6 and 48.7%, respec- tively, whereas waxy starch contained only a trace (0.04%) of amylose. There was little difference in isoamylase-debranched amylopectin between nonwaxy and high-amylose barley, whereas amylopectin from waxy bar- ley had a significantly higher percentage of fraction with degree

Z. Czuchajowska; A. Klamczynski; B. Paszczynska; B.-K. Baik



Modification of starch during malting of sorghum  

E-print Network

STARCH DEGRADATION AND LOSS STARCH QUANTIFICATION USING HPSEC. . . . . . . . . . . . LOW MOLECULAR WEIGHT CARBOHYDRATE QUANTIFICATION USING HPLC EFFECT OF MALTING ON NUTRITIVE VALUE OF SORGHUM OPAQUE BEER PRODUCTION LAGER BEER PRODUCTION LAGER... 38. Apparent molecular weight standard curve for HPSEC . 139 39. Glucose, fructose, maltose, and standard curves for HPLC analysis . . 142 40. Oligosaccharide standard curve for HPLC analysis . . 147 LIST OF FIGURES Figure 1. Dry matter losses...

Floyd, Cherie Diane



Salt-starch xylose lysine deoxycholate agar  

Microsoft Academic Search

Salt dependent gram-negative bacilli responsible for gastroenteritis and tissue infections are often not recovered because proper media for isolation are not used. A salt-starch XLD agar with 1.5% NaCl and 0.5% starch medium has been found to permit the isolation of pathogenic Enterobacteriaceae, non-Enterobacteriaceae gram-negative bacilli, and salt-dependent gram-negative bacilli, among which isVibrio parahemolyticus. As far as the Enterobacteriaceae are

Fredy P. Roland



Biodegradable starch-based polymeric materials  

NASA Astrophysics Data System (ADS)

The effects of low-molecular-weight additives, temperature and mechanical action on the structure and properties of starch are discussed. Special attention is given to mixtures of starch with synthetic polymers, e.g., co-polymers of ethylene with vinyl acetate, vinyl alcohol, acrylic acid, cellulose derivatives and other natural polymers. These mixtures can be used in the development of novel environmentally safe materials (films, coatings, packaging materials) and various articles for short-term use. The bibliography includes 105 references.

Suvorova, Anna I.; Tyukova, Irina S.; Trufanova, Elena I.



Color Quiz  

NSDL National Science Digital Library

Please take this Quiz. It is not that hard. Remember If you understand color, you will be able to use color in your artwork more effectively. For your Quiz please answer the 18 questions below. Here are some sites you have already seen that will help you answer the questions. Color Theory Color Vocabulary Wikipedia color theory You may write your answers down on a piece of paper or you can type the answers up. Make sure name, period, and date are on assignment ...

Ms. Freeman



Color Quiz  

NSDL National Science Digital Library

Please take this Quiz. It is not that hard. Remember If you understand color, you will be able to use color in your artwork more effectively. For your Quiz please answer the 18 questions below. Here are some sites you have already seen that will help you answer the questions. Color Theory Color Vocabulary Wikipedia color theory You may write your answers down on a piece of paper or you can type the answers up. Make sure name, period, and date are on assignment ...




Rhabdomyomas and Tuberous sclerosis complex: our experience in 33 cases  

PubMed Central

Background Rhabdomyomas are the most common type of cardiac tumors in children. Anatomically, they can be considered as hamartomas. They are usually randomly diagnosed antenatally or postnatally sometimes presenting in the neonatal period with haemodynamic compromise or severe arrhythmias although most neonatal cases remain asymptomatic. Typically rhabdomyomas are multiple lesions and usually regress spontaneously but are often associated with tuberous sclerosis complex (TSC), an autosomal dominant multisystem disorder caused by mutations in either of the two genes, TSC1 or TSC2. Diagnosis of tuberous sclerosis is usually made on clinical grounds and eventually confirmed by a genetic test by searching for TSC genes mutations. Methods We report our experience on 33 cases affected with rhabdomyomas and diagnosed from January 1989 to December 2012, focusing on the cardiac outcome and on association with the signs of tuberous sclerosis complex. We performed echocardiography using initially a Philips Sonos 2500 with a 7,5/5 probe and in the last 4 years a Philips IE33 with a S12-4 probe. We investigated the family history, brain, skin, kidney and retinal lesions, development of seizures, and neuropsychiatric disorders. Results At diagnosis we detected 205 masses, mostly localized in interventricular septum, right ventricle and left ventricle. Only in 4 babies (12%) the presence of a mass caused a significant obstruction. A baby, with an enormous septal rhabdomyoma associated to multiple rhabdomyomas in both right and left ventricular walls died just after birth due to severe heart failure. During follow-up we observed a reduction of rhabdomyomas in terms of both number and size in all 32 surviving patients except in one child. Eight patients (24,2%) had an arrhythmia and in 2 of these cases rhabdomyomas led to Wolf-Parkinson-White Syndrome. For all patients the arrhythmia spontaneously totally disappeared or was reduced gradually. With regarding to association with tuberous sclerosis, we diagnosed tuberous sclerosis clinically in 31 babies (93,9%). Conclusion Rhabdobyomas are tumors with favorable prognosis because they frequently do not cause symptoms and they often regress in numbers and size. Nevertheless, due to frequent association with tuberous sclerosis complex and the resulting neurological impairment, the prognosis can result unfavorable. PMID:24884933



Morphological features and physicochemical properties of waxy wheat starch.  


Morphological features, granule composition, and physicochemical properties of waxy wheat starch were compared with those of normal wheat starch. The morphologies and granule populations were found to be similar for the two starches. However, waxy wheat starch contained a smaller proportion of B-type granules, had a larger average granule diameter, and a higher degree of crystallinity than normal wheat starch, as measured by particle size analysis and differential scanning calorimetry. These differences resulted in a higher gelatinization temperature, transition enthalpy, peak viscosity, breakdown, swelling power, lower peak viscosity temperature and final viscosity in waxy wheat starch. These points suggest that waxy wheat starch should have greater resistance to retrogradation during cooling and higher water-holding capacity under dry conditions. Highlighting the differences in physicochemical properties of waxy and normal wheat starches should help point toward effective applications of waxy wheat starch in the food industry. PMID:24076202

Zhang, Huanxin; Zhang, Wei; Xu, Chunzhong; Zhou, Xing



Physicochemical properties and digestibility of hydrothermally treated waxy rice starch.  


Waxy rice starch was subjected to annealing (ANN) and heat-moisture treatment (HMT). These starches were also treated by a combination of ANN and HMT. The impact of single and dual modifications (ANN-HMT and HMT-ANN) on the molecular weight (M(w)), crystalline structure, thermal properties, and the digestibility were investigated. The relative crystallinity and short-range order on the granule surface increased on ANN, whereas decreased on HMT. All treated starches showed lower M(w) than that of the native starch. Gelatinization onset temperature, peak temperature and conclusion temperature increased for both single and dual treatments. Increased slowly digestible starch content was found on HMT and ANN-HMT. However, resistant starch levels decreased in all treated starches as compared with native starch. The results would imply that hydrothermal treatment induced structural changes in waxy rice starch significantly affected its digestibility. PMID:25442528

Zeng, Feng; Ma, Fei; Kong, Fansheng; Gao, Qunyu; Yu, Shujuan



Phosphoglucan phosphatase function sheds light on starch degradation.  


Phosphoglucan phosphatases are novel enzymes that remove phosphates from complex carbohydrates. In plants, these proteins are vital components in the remobilization of leaf starch at night. Breakdown of starch is initiated through reversible glucan phosphorylation to disrupt the semi-crystalline starch structure at the granule surface. The phosphoglucan phosphatases starch excess 4 (SEX4) and like-SEX4 2 (LSF2) dephosphorylate glucans to provide access for amylases that release maltose and glucose from starch. Another phosphatase, LSF1, is a putative inactive scaffold protein that may act as regulator of starch degradative enzymes at the granule surface. Absence of these phosphatases disrupts starch breakdown, resulting in plants accumulating excess starch. Here, we describe recent advances in understanding the biochemical and structural properties of each of these starch phosphatases. PMID:24534096

Silver, Dylan M; Kötting, Oliver; Moorhead, Greg B G



Color Categories and Color Appearance  

ERIC Educational Resources Information Center

We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

Webster, Michael A.; Kay, Paul




Technology Transfer Automated Retrieval System (TEKTRAN)

Starch-oil composites (SOCs) are stable suspensions of microscopic (1-10 um) oil droplets in a starch dispersion or gel. These dispersions can be dried and reconstituted into an aqueous system without the need for emulsifiers, yet will maintain their physical stability and properties. SOCs have be...



Technology Transfer Automated Retrieval System (TEKTRAN)

This technique allows the accurate prediction of the moisture content of native starch and starch-based materials using direct-current conductance that conforms to established protocols. The technique uses currently available technology and can be used to measure the moisture content of homogenous p...


Characterization of enzyme-resistant starch in maize amylose-extender mutant starches  

Technology Transfer Automated Retrieval System (TEKTRAN)

In the human digestive system, a type of starch known as resistant starch (RS) can not be digested. RS is not absorbed in the small intestine, and is passed to the large intestine where it is fermented by bacteria to produce short-chain fatty acids, which have anti-cancer and anti-inflammatory prop...


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

PubMed Central

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

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



Resistant Starch and Starch Thermal Characteristics in Exotic Corn Lines Grown in Temperate and Tropical Environments  

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


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


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). PMID:24594151

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



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


In this study, partial 4-?-glucanotransferase (4?GT) treatment was used to modulate the fine structure responsible for the slow digestion and resistant property of starch. Normal corn starch modified using 4?GT 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 4?GT treatment decreased the content of amylose from 32.6% to 26.8%. The molecular weight distribution and chain length distribution of 4?GT-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 4?GT-treated starch. These results suggested that the 4?GT modified starch synthesized the novel amylopectin clusters with slow digestible and resistant character. PMID:24463262

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




Technology Transfer Automated Retrieval System (TEKTRAN)

Starch is one of the most abundant farm-based raw materials. It is a significant component of such high volume commodity crops as corn, potato, rice, wheat, and barley. Because of the large surplus of these crops over demand, there is a great deal of interest in developing new uses for starch-base...


Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films  

NASA Astrophysics Data System (ADS)

In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch-glycerol and potato starch-glycerol-surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films.

Cie?la, Krystyna; Watzeels, Nick; Rahier, Hubert



Processing of Color Words Activates Color Representations  

ERIC Educational Resources Information Center

Two experiments were conducted to investigate whether color representations are routinely activated when color words are processed. Congruency effects of colors and color words were observed in both directions. Lexical decisions on color words were faster when preceding colors matched the color named by the word. Color-discrimination responses…

Richter, Tobias; Zwaan, Rolf A.



In vitro tuberization of potato sprouts as affected by ethrel and gibberellic acid  

Microsoft Academic Search

Summary  In vitro tuberization of etiolated potato sprouts was considerably advanced by a dose of 50 ppm ethrel (2-chloro-ethyl-phosphonic\\u000a acid). The adition of ethrel also increased the number of tubers, produced shorter and thicker stolons and reduced root development.\\u000a Some of these effects are opposite to those induced by gibberellic acid which is known to retard tuberization and to promote\\u000a elongation.

L. Garcia-Torres; C. Gomez-Campo



Effect of a continuous hot water treatment of potato tubers on seed-borne fungal pathogens  

Microsoft Academic Search

Summary  The viability of five pathogens was decreased by treatment with hot water when tested in vitro.Polyscytalum pustulans was most sensitive andRhizoctonia solani least sensitive.\\u000a \\u000a Potato tubers were exposed to 55C for 5 min in a commercial continuous hot water treatment plant using naturally contaminated\\u000a seed tubers and tubers which had been inoculated by dipping in comminuted cultures. The frequency of

E. P. Dashwood; E. M. Burnett; M. C. M. Perombelon



In vitro mass tuberization and virus-free seed-potato production in Taiwan  

Microsoft Academic Search

This is the first report ofin vitro tuberization becoming feasible for agriculture in seed-potato production. The optimum condition forin vitro mass tuberization of virus-free potatoes were: 10 mg\\/1 BA, 8% sucrose. 20°C incubating temperature, and eight hours of 100\\u000a lux incubation photoperiod. An estimated 36,000 dormant, miniature tubers were harvested from the aseptic containers incubated\\u000a on a 10m2 bench area

Po-jen Wang; Ching-yeh Hu



Relation of potato tuber growth and skin maturity to infection by common scab, Streptomyces scabies  

Microsoft Academic Search

Summary  Cut surfaces of tuber tissue of either resistant or susceptible varieties permitted abundant, macroscopically visible growth\\u000a ofS. scabies after being autoclaved or fumigated with propylene oxide. Sparse aerial mycelium developed on freshly cut, washed tuber surfaces.\\u000a In contrast, macroscopically visible growth ofS. scabies was prevented by intact skin surfaces of mature tubers which had been washed only, or autoclaved, or

W. J. Hooker; O. T. Page



Color Analysis  

NASA Astrophysics Data System (ADS)

Color, flavor, and texture are the three principal quality attributes that determine food acceptance, and color has a far greater influence on our judgment than most of us appreciate. We use color to determine if a banana is at our preferred ripeness level, and a discolored meat product can warn us that the product may be spoiled. The marketing departments of our food corporations know that, for their customers, the color must be "right." The University of California Davis scorecard for wine quality designates four points out of 20, or 20% of the total score, for color and appearance (1). Food scientists who establish quality control specifications for their product are very aware of the importance of color and appearance. While subjective visual assessment and use of visual color standards are still used in the food industry, instrumental color measurements are extensively employed. Objective measurement of color is desirable for both research and industrial applications, and the ruggedness, stability, and ease of use of today's color measurement instruments have resulted in their widespread adoption.

Wrolstad, Ronald E.; Smith, Daniel E.


Color categories and color appearance.  


We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary were perceptually exaggerated. This task did not require overt judgments of the perceived colors, and the tendency to group showed only a weak and inconsistent categorical bias. In a second case, we analyzed results from two prior studies of hue scaling of chromatic stimuli (De Valois, De Valois, Switkes, & Mahon, 1997; Malkoc, Kay, & Webster, 2005), to test whether color appearance changed more rapidly around the blue-green boundary. In this task observers directly judge the perceived color of the stimuli and these judgments tended to show much stronger categorical effects. The differences between these tasks could arise either because different signals mediate color grouping and color appearance, or because linguistic categories might differentially intrude on the response to color and/or on the perception of color. Our results suggest that the interaction between language and color processing may be highly dependent on the specific task and cognitive demands and strategies of the observer, and also highlight pronounced individual differences in the tendency to exhibit categorical responses. PMID:22176751

Webster, Michael A; Kay, Paul



Tuberous sclerosis complex: everything old is new again  

Microsoft Academic Search

Tuberous Sclerosis Complex (TSC) is a multiorgan genetic disease caused by loss of function of either the TSC1 (encodes hamartin) or TSC2 (encodes tuberin) genes. Patients with TSC have benign tumors (hamartomas) in multiple organs though brain involvement is\\u000a typically the most disabling aspect of the disease as very high rates of neurodevelopmental disorders are seen. While first\\u000a described well

Kevin C. Ess



Hepatotoxicity of tubers of Indian Kudzu ( Pueraria tuberosa) in rats  

Microsoft Academic Search

Methanolic extract of tubers of Pueraria tuberosa Linn. (Fabaceae) (PTME) has been tested for hepatoxicity in rats. In acute study, PTME (100–400mg\\/100g BW, given orally) showed LD50 at 227.5mg. For sub-chronic study, its repeated doses (5–100mg\\/100g BW, for 30days), significantly increased hepatic enzymes in blood, sinusoidal congestion, disruption of central vein, inflammatory cell infiltration and hepatocellular necrosis in liver in

Nagwani Santosh; Kumar Mohan; Singh Royana; Tripathi B. Yamini



The pathogenesis and imaging of the tuberous sclerosis complex  

Microsoft Academic Search

Tuberous sclerosis complex (TSC) is an autosomal-dominant disorder characterized by the formation of hamartomatous lesions\\u000a in multiple organ systems. It is the second most common neurocutaneous syndrome after neurofibromatosis type 1 and has been\\u000a recognized since the late 1800s. Although the disease has complete penetrance, there is also high phenotypic variability:\\u000a some patients have obvious signs at birth, while others

Henry J. Baskin Jr



TuberQ: a Mycobacterium tuberculosis protein druggability database.  


In 2012 an estimated 8.6 million people developed tuberculosis (TB) and 1.3 million died from the disease [including 320?000 deaths among human immunodeficiency virus (HIV)-positive people]. There is an urgent need for new anti-TB drugs owing to the following: the fact that current treatments have severe side effects, the increasing emergence of multidrug-resistant strains of Mycobacterium tuberculosis (Mtb), the negative drug-drug interactions with certain HIV (or other disease) treatments and the ineffectiveness against dormant Mtb. In this context we present here the TuberQ database, a novel resource for all researchers working in the field of drug development in TB. The main feature of TuberQ is to provide a druggability analysis of Mtb proteins in a consistent and effective manner, contributing to a better selection of potential drug targets for screening campaigns and the analysis of targets for structure-based drug design projects. The structural druggability analysis is combined with features related to the characteristics of putative inhibitor binding pockets and with functional and biological data of proteins. The structural analysis is performed on all available unique Mtb structures and high-quality structural homology-based models. This information is shown in an interactive manner, depicting the protein structure, the pockets and the associated characteristics for each protein. TuberQ also provides information about gene essentiality information, as determined from whole cell-based knockout experiments, and expression information obtained from microarray experiments done in different stress-related conditions. We hope that TuberQ will be a powerful tool for researchers working in TB and eventually will lead to the identification of novel putative targets and progresses in therapeutic activities. Database URL: PMID:24816183

Radusky, Leandro; Defelipe, Lucas A; Lanzarotti, Esteban; Luque, Javier; Barril, Xavier; Marti, Marcelo A; Turjanski, Adrián G



Pathogenicity of Streptomyces scabies on Potato Tubers cultured in vitro  

Microsoft Academic Search

IN potato breeding trials conducted here extensive investigations are required to determine the relative resistance of selected seedlings to the common scab disease caused by Streptomyces scabies (Thaxt.) Waksman and Henrici. The tissue-culture technique1,2 for establishing a ready source of aseptic tubers potentially offers a rapid and convenient method for indexing their resistance and for studies on the host-parasite interactions.

C. H. Lawrence; W. G. Barker



Generic Delimitations in Tuberous Periplocoideae (Apocynaceae) from Africa and Madagascar  

PubMed Central

• Background and Aims The number of genera included in Apocynaceae subfamily Periplocoideae is a matter of debate. DNA sequences are used here as an independent dataset to clarify generic relationships and classification of the tuberous periplocoid genera and to address the question of the phylogenetic interpretation of pollinia formation in Schlechterella. • Methods Representatives of nearly all African and Malagasy genera of Periplocoideae possessing root tubers were analysed using ITS and plastid DNA sequence characters. • Key Results Sequence data from non?coding molecular markers (ITS of nrDNA and the trnT?L and trnL?F spacers as well as the trnL intron of plastid DNA) give support for a broad taxonomic concept of Raphionacme including Pentagonanthus. Together with Schlechterella, which is sister to Raphionacme, all Raphionacme?like taxa form a derived monophyletic group of somewhat diverse species. Sister to the Schlechterella/Raphionacme clade is a clade comprising Stomatostemma and the not truly tuberous vine Mondia. In the combined analysis, sister to these two clades combined is a clade formed by Petopentia natalensis and Periploca. • Conclusions The recent inclusion of the monotypic South African Petopentia in the monotypic Malagasy endemic Ischnolepis is to be rejected. The Malagasy Camptocarpus is sister to the remainder of Periplocoideae in the ITS and combined analyses, and a Malagasy origin for the subfamily is discussed. PMID:14980976




Antimicrobial activity of Curcuma zedoaria and Curcuma malabarica tubers.  


The antimicrobial activity of extracts of Curcuma zedoaria and Curcuma malabarica tubers was tested against six bacterial and two fungal strains using the agar well diffusion and broth dilution methods. Petroleum ether, hexane, chloroform, acetone and ethanol extracts exhibited antibacterial as well as antifungal activity. Acetone and hexane extracts of both tubers showed comparable antimicrobial activity as indicated by minimum inhibitory concentration (MIC) values, but other extracts of Curcuma malabarica showed significantly lower activity than those of Curcuma zedoaria. The MIC values for different strains and extracts ranged from 0.01 to 0.15 mg/ml in Curcuma zedoaria and from 0.01 to 0.94 mg/ml in Curcuma malabarica. Staphylococcus aureus (Gram positive) was inhibited by Curcuma malabarica but not by Curcuma zedoaria. This study is the first report of the antimicrobial properties of Curcuma malabarica. The findings also support the use of Curcuma zedoaria tubers in traditional medicine for the treatment of bacterial and fungal infections. PMID:15848035

Wilson, B; Abraham, G; Manju, V S; Mathew, M; Vimala, B; Sundaresan, S; Nambisan, B



Studies on antimicrobial efficacy of medicinal tuberous shrub Talinum cuneifolium.  


Talinum cuneifolium (Vahl.) Willd. an erect shrub with subterranian tuber (Portulacaceae) is endowed with wide range of pharmacological activities. The antimicrobial efficacy of the plant is evaluated against three bacteria and two fungal species by disc diffusion method. Preliminary phytochemical screening was carried out among hexane, ethylacetate, methanolic extracts of leaf and roottuber for different potent chemicals. The leaf methanolic extract of T cuneifolium showed maximum effect on the growth of Proteus (25.8 mm) followed by Bacillus (24.62 mm) and E. coli (19.42 mm). The tuberous methanolic extract of T cuneifolium showed maximum effect on growth of Proteus (28.15 mm) followed by Bacillus (26.88 mm) and E. coli (24.51 mm). The Gram-positive bacterial strains (Bacillus) were more susceptible to the extractions of T cuneifolium as compared to Gram-negative bacteria (E. coli, Pseudomonas aeruginosa, Proteus vulgaris and Klebsiella pneumoneia). The antifungal activity of selected plant leaf and root tubers exhibit pronounced activity against Candida albicans rather than Aspergillus niger. These studies showed that the methanolic extracts of T cuneifolium plant parts were certainly much better and powerful. This may be due to the better solubility of the action components in organic solvent. PMID:23360007

Savithramma, N; Ankanna, S; Rao, M Linga; Saradvathi, J



The effects of auxin and strigolactones on tuber initiation and stolon architecture in potato  

PubMed Central

Various transcriptional networks and plant hormones have been implicated in controlling different aspects of potato tuber formation. Due to its broad impact on many plant developmental processes, a role for auxin in tuber initiation has been suggested but never fully resolved. Here, auxin concentrations were measured throughout the plant prior to and during the process of tuber formation. Auxin levels increase dramatically in the stolon prior to tuberization and remain relatively high during subsequent tuber growth, suggesting a promoting role for auxin in tuber formation. Furthermore, in vitro tuberization experiments showed higher levels of tuber formation from axillary buds of explants where the auxin source (stolon tip) had been removed. This phenotype could be rescued by application of auxin on the ablated stolon tips. In addition, a synthetic strigolactone analogue applied on the basal part of the stolon resulted in fewer tubers. The experiments indicate that a system for the production and directional transport of auxin exists in stolons and acts synergistically with strigolactones to control the outgrowth of the axillary stolon buds, similar to the control of above-ground shoot branching. PMID:22689826

Bachem, Christian W.B.



Starches of varied digestibilities differentially modify intestinal function in rats.  


Starches of different digestibilities may enter the colon to different extents and alter colonic function. Male Fischer 344 rats were fed diets containing 25% cooked potato starch, arrowroot starch, high amylose cornstarch or raw potato starch for 6 wk. Fecal weight, transit time, colonic thymidine kinase activity (a marker for cell proliferation), and weight, starch content and pH of the cecum and proximal and distal colon were measured. Raw potato starch was much less completely digested than high amylose cornstarch, resulting in a 32-fold greater amount of undigested starch entering the cecum in the raw potato starch group. Both the high amylose cornstarch and raw potato starch diets significantly enhanced fecal weight and produced large intestinal hypertrophy, effects that were greatest in the raw potato starch group. Raw potato starch feeding was associated with the highest level of thymidine kinase activity, although the differences in thymidine kinase activity among the four groups were not significant. This diet also produced a 50% longer transit time. Entry of a large amount of raw potato starch into the colon resulted in greater luminal acidity, greater luminal bulk and slower transit. A much smaller amount of starch entered the colon in the high amylose cornstarch group and resulted in fecal bulking but no alteration in transit. PMID:8263598

Lajvardi, A; Mazarin, G I; Gillespie, M B; Satchithanandam, S; Calvert, R J



The Role of Gibberellin, Abscisic Acid, and Sucrose in the Regulation of Potato Tuber Formation in Vitro1  

PubMed Central

The effects of plant hormones and sucrose (Suc) on potato (Solanum tuberosum L.) tuberization were studied using in vitro cultured single-node cuttings. Tuber-inducing (high Suc) and -noninducing (low Suc or high Suc plus gibberellin [GA]) media were tested. Tuberization frequencies, tuber widths, and stolon lengths were measured during successive stages of development. Endogenous GAs and abscisic acid (ABA) were identified and quantified by high-performance liquid chromatography and gas chromatography-mass spectrometry. Exogenous GA4/7 promoted stolon elongation and inhibited tuber formation, whereas exogenous ABA stimulated tuberization and reduced stolon length. Indoleacetic acid-containing media severely inhibited elongation of stolons and smaller sessile tubers were formed. Exogenous cytokinins did not affect stolon elongation and tuber formation. Endogenous GA1 level was high during stolon elongation and decreased when stolon tips started to swell under inducing conditions, whereas it remained high under noninducing conditions. GA1 levels were negatively correlated with Suc concentration in the medium. We conclude that GA1 is likely to be the active GA during tuber formation. Endogenous ABA levels decreased during stolon and tuber development, and ABA levels were similar under inducing and noninducing conditions. Our results indicate that GA is a dominant regulator in tuber formation: ABA stimulates tuberization by counteracting GA, and Suc regulates tuber formation by influencing GA levels. PMID:9625710

Xu, Xin; van Lammeren, André A.M.; Vermeer, Evert; Vreugdenhil, Dick



Association mapping of starch physicochemical properties with starch biosynthesizing genes in waxy rice (Oryza sativa L.).  


Waxy (glutinous) rice is widely used in traditional foods, and understanding the genetic bases of its diverse physicochemical properties will contribute to breeding of new waxy rice with unique qualities. The objective of this study was to investigate the genetic relationship between the starch biosynthesis related genes and the physicochemical properties of waxy rice using association mapping. A total of 36 molecular markers representing 18 genes were used to genotype 50 waxy rice accessions for which starch properties were previously available. Most of the starch properties differed between high and low gelatinization temperature (GT) groups, whereas most traits were similar between the low-GT indica rice and low-GT japonica rice, suggesting GT was the main determinant of the starch quality of waxy rice. Association mapping indicated that the starch properties of waxy rice were mainly controlled by starch synthase IIa (SSIIa or SSII-3, a major gene responsible for the gelatinization temperature) and SSI. It was found that gene-gene interactions were also important for the genetic control of starch properties of waxy rice. This study suggests that application of the functional SNPs of SSIIa in molecular breeding may facilitate quality improvement of waxy rice. PMID:24063600

Xu, Feifei; Zhang, Gan; Tong, Chuan; Sun, Xiao; Corke, Harold; Sun, Mei; Bao, Jinsong



Physical characterisation of high amylose maize starch and acylated high amylose maize starches.  


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 HAMSBstarch granules by NMR spectroscopy with Carr-Purcell-Meiboom-Gill (CMPG) experiments showed that T2 long was reduced in acylated starches and that drying and storage of the starch granules further reduced T2 long. Analysis of the Free Induction Decay (FID) focussing on the short components of T2 (correlated to the solid matrix), indicated that drying and subsequent storage resulted in alterations of starch at 0.33a(w) and that these changes were reduced with acylation. In vitro enzymatic digestibility of heated starch dispersions by bacterial ?-amylase was increased by acylation (HAMSstarch. PMID:25498636

Lim, Ya-Mei; Hoobin, Pamela; Ying, DanYang; Burgar, Iko; Gooley, Paul R; Augustin, Mary Ann



Color Lines.  

ERIC Educational Resources Information Center

Teaching about color and value scales emphasizes a systematic approach to the effects of color and may reinforce assumptions rooted in racism. Describes how an 8th grade art class challenged the symbolism of black as evil and white as good. By showing that this is a culturally constructed meaning, art teachers model that such meaning can also be…

Gude, Olivia



Retention of Cationic Starch onto Cellulose Fibres  

NASA Astrophysics Data System (ADS)

Three methods of cationic starch titration were used to quantify its retention on cellulose fibres, namely: (i) the complexation of CS with iodine and measurement of the absorbency of the ensuing blue solution by UV-vis spectroscopy; (ii) hydrolysis of the starch macromolecules followed by the conversion of the resulting sugars to furan-based molecules and quantifying the ensuing mixture by measuring their absorbance at a ? of 490 nm, using the same technique as previous one and; finally (iii) hydrolysis of starch macromolecules by trifluoro-acetic acid and quantification of the sugars in the resulting hydrolysates by high performance liquid chromatography. The three methods were found to give similar results within the range of CS addition from 0 to 50 mg per g of cellulose fibres.

Missaoui, Mohamed; Mauret, Evelyne; Belgacem, Mohamed Naceur




Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this study was to evaluate the functions and structures of starches from exotic x adapted inbred lines and exotic breeding crosses (exotic populations x adapted lines), and to establish the relationship between the fine structure and functional properties of the starches. Starches ...



Microsoft Academic Search

Despite long-established recognition of differences in the histologie features of starch granules obtained from various plant materials, and more recent knowledge of the chemical heterogeneity of their starch-components, rather scant at tention has been directed toward studies of the relative utilizations of starches as food for man and animals. The paucity of information on the relative food values of un



HRP-Mediated Synthesis of Starch-Polyacrylamide Graft Copolymers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Modified starch-based polymers can be engineered for specific properties by combining starch with synthetic polymers through graft copolymerization. Polyacrylamide grafted starches have received a great deal of applications in areas such as superabsorbent paper-making additives, drag reduction and ...


HRP-Mediated Synthesis of Starch-Polyacrylamide Graft Copolymers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Modified starch-based polymers can be engineered for specific properties by combining starch with synthetic polymers through graft copolymerization. Polyacrylamide grafted starch have received a great deal of applications in areas such as superabsorbent paper-making additives, drag reduction and te...


The influence of amylose on starch granule structure  

Microsoft Academic Search

Starch granules are principally composed of the two glucose polymers amylose and amylopectin. Native starch granules typically contain around 20% amylose and 80% amylopectin. However, it is possible to breed plants that produce starch with very different amylose and amylopectin contents. At present, the precise structural roles played by these two polymers are incompletely understood. In this study, small-angle X-ray

P. J. Jenkins; A. M. Donald




Technology Transfer Automated Retrieval System (TEKTRAN)

Physicochemical properties of acorn (Quercus palustris) starch were studied. Acorn starch granules were spherical or ovoid, with diameters ranging from 3-17 micrometers. Acorn starch exhibited A-type X-ray diffraction pattern, an apparent amylose content of 43.4% and absolute amylose content of 25...


Biodegradable Multiphase Systems Based on Plasticized Starch: A Review  

Microsoft Academic Search

The aim of this review is to show the relationships between the structure, the process, and the properties of biodegradable multiphase systems based on plasticized starch (PLS), the so?called “thermoplastic starch.” These mutiphase materials are obtained when associating association between plasticized starches and other biodegradable materials, such as biodegradable polyesters [polycaprolactone (PCL), polyhydroxyalkanoates (PHAs), polylactic acid (PLA), polyesteramide (PEA), aliphatic,

Luc Avérous




Technology Transfer Automated Retrieval System (TEKTRAN)

Whey proteins are increasingly being combined with starches and flours to make nutritious extruded snacks. The effect of whey proteins on the rheological properties of starch was investigated. The paste viscosity of starches Amioca (~0.5% amylose), native corn (~27% amylose), Hylon VII (~70% amylose...


Rheological behaviour of sago ( Metroxylon sagu) starch paste  

Microsoft Academic Search

Rheological behaviour of gelatinized sago starch solution was studied over the shear rate range of 13.61–704 s?1 at various concentration and temperature ranges. A power law equation was used to describe the rheological behaviour of the starch solution, while the effect of temperature was evaluated by the Arrhenius equation. The effect of starch concentration on apparent viscosity was studied using

Mohd Nurul I; B. M. N Mohd. Azemi; D. M. A Manan




Technology Transfer Automated Retrieval System (TEKTRAN)

Elevated levels of starch in sugarcane juice adversely affect the processing quality of raw and refined sugar. Despite reports of differences among cultivars for starch content, most research has focused on processing aids to minimize the negative processing effects of starch. Deploying cultivars ...



Technology Transfer Automated Retrieval System (TEKTRAN)

Chemical and physical properties of kiwifruit (Actinidia deliciosa var. ‘Hayward’) starch were studied. Kiwifruit starch granules were compound, irregular, or dome-shaped with diameters predominantly 4-5 micrometers or 7-9 micrometers. Kiwifruit starch exhibited B-type X-ray diffraction pattern, a...


The role of siderophores in potato tuber yield increase by Pseudomonas putida in a short rotation of potato  

Microsoft Academic Search

The effect of treatment of potato seed tubers withPseudomonas putida isolate WCS358 on tuber yield was studied in different crop rotations at the Experimental Farm ‘De Schreef’, near Lelystad. With untreated, tuber yield in a 1:3 (short) rotation compared to yield in a 1:6 (long) rotation of potato was decreased by 11% at 86 days (seed tuber harvest) and by

P. A. H. M. Bakker; J. G. Lamers; A. W. Bakker; J. D. Marugg; P. J. Weisbeek; B. Schippers



Tuber Water and Pressure Potentials Decrease and Sucrose Contents Increase in Response to Moderate Drought and Heat Stress  

Technology Transfer Automated Retrieval System (TEKTRAN)

Environmental stress during the growing season can reduce the quality of stored Solanum tuberosum (potato) tubers. Sugar end defect is a serious quality concern for growers and processors of russet potatoes that is initiated by drought or heat stress. Changes in tuber water potential and tuber compo...


Cover crops alter the soil microbial community and increase potato tuber yield and quality  

Technology Transfer Automated Retrieval System (TEKTRAN)

An on-going study at a commercial farm operation in the San Luis Valley, CO is examining the effect of various summer cover crops (mustard, canola, sorghum-sudangrass, and a wet fallow control) on potato tuber yield and quality. In four of the five years, potato tuber yield and quality has shown si...


Reversal of learning deficits in a Tsc2+/ mouse model of tuberous sclerosis  

E-print Network

,7. Here we report that mice with a heterozygous, inactivating mutation in the Tsc2 gene (Tsc2+/­ mice)8Reversal of learning deficits in a Tsc2+/­ mouse model of tuberous sclerosis Dan Ehninger1 Silva1 Tuberous sclerosis is a single-gene disorder caused by heterozygous mutations in the TSC1 (9q34

Silva, Alcino


The role of endophytic bacteria during seed piece decay and potato tuberization  

Microsoft Academic Search

Healthy potato tubers (Solanum tuberosum L.) cv. Kennebec were found to be internally colonized by non-pathogenic bacterial populations originating from root zone soil. These endophytic bacteria were categorized, on the basis of bioassays, as plant growth promoting (PGP), plant growth retarding (PGR) and plant growth neutral (PGN). Genera isolated from tubers included Pseudomonas, Bacillus, Xanthomonas, Agrobacterium, Actinomyces and Acinetobacter. The

A. V. Sturz



The pink eye syndrome does not impair tuber fresh cut wound-related responses  

Technology Transfer Automated Retrieval System (TEKTRAN)

The potato tuber pink eye (PE) syndrome is a costly physiological disorder that results in corruption of the native periderm, susceptibility to infection, water vapor loss and associated shrinkage, roughened and cracked tuber surfaces, and various related blemishes and defects. PE results in aberra...


Effect of different genotypes of Phytophthora infestans (Mont. de Bary) and temperature on tuber disease development  

E-print Network

Effect of different genotypes of Phytophthora infestans (Mont. de Bary) and temperature on tuber Lines (ABL) of potato with different genotypes of the potato late blight pathogen (Phytophthora resistance. The US-8 genotype isolates were the most aggressive in tubers in most years causing rapid

Douches, David S.


Tuber Dormancy Lasting Eight Years in the Wild Potato Solanum Jamesii  

Technology Transfer Automated Retrieval System (TEKTRAN)

The physiology of tuber dormancy is of practical interest for commercial potato as it is related to efficient storage of the crop, and vigorous and uniform sprouting of planted seed tubers. It is also of interest for germplasm preservation at the genebank. Since research is often advanced by study...


Tuber Dormancy Lasting Eight Years in the Wild Potato Solanum Jamesii  

Technology Transfer Automated Retrieval System (TEKTRAN)

Control of tuber dormancy is of interest for commercial potato production and for germplasm preservation in the genebank. Solanum jamesii plants were collected by the author from the wild in New Mexico and Arizona, USA in 1998 and grown in the greenhouse. Tubers harvested in 1999 were placed in pape...


Phytochrome B Affects the Levels of a Graft-Transmissible Signal Involved in Tuberization1  

PubMed Central

Grafting experiments between phytochrome B antisense and wild-type potato (Solanum tuberosum L. subsp. andigena [line 7540]) plants provide evidence that phytochrome B is involved in the production of a graft-transmissible inhibitor of tuberization, the level of which is reduced in the antisense plants, allowing them to tuberize in noninducing photoperiods. PMID:9576771

Jackson, Stephen D.; James, Pat; Prat, Salomé; Thomas, Brian



Aquatic plant shows flexible avoidance by escape from tuber predation by swans  

Microsoft Academic Search

Deeper burial of bulbs and tubers has been suggested as an escape against below-ground herbivory by vertebrates, but experimental evidence is lacking. As deep propagule burial can incur high costs of emergence after dormancy, burial depth may represent a trade-off between sprouting survival and herbivore avoidance. We tested whether burial depth of subterraneous tubers is a flexible trait in fennel

B. Hidding; M. R. J. Klaassen; T. De Boer; P. P. De Vries; B. A. Nolet



Role of Growth Promoting Substances in Breaking Potato (Solanum tuberosum L.) Tuber Dormancy  

Microsoft Academic Search

The present investigation was conducted to determine the effect of benzyl adenine (BA), spermine (Spr) and cycocel (CCC) alone and in combination in different concentrations for breaking dormancy, growth and tuberization of two potato cultivars Diamant and Desiree. The experiment was conducted in pots under natural condition. Fresh harvested potato tubers were collected from National Agriculture Research Centre, Islamabad and



Inactivation of trypsin inhibitors in sweet potato and taro tubers during processing  

Microsoft Academic Search

In order to understand the extent of elimination of trypsininhibitors during processing of sweet potato (Ipomoea batatas) andtaro (Colocasia esculenta) tubers, a detailed study was conductedusing tubers processed by oven drying, cooking, and microwavebaking. Between 80 and 90% trypsin inhibitor (TI) activity wasretained in sweet potato chips up to 2h at 70 °C. Among thefour cultivars of sweet potatoes, RS-III-2

K. Sasi Kiran; G. Padmaja



Renal involvement in tuberous sclerosis complex and von Hippel–Lindau disease: shared disease mechanisms?  

Microsoft Academic Search

Tuberous sclerosis complex and von Hippel–Lindau disease are distinct autosomal dominant tumor suppressor syndromes that can exhibit similar renal phenotypes and seem to share some signaling pathway components. Similarities exist in the current clinical management of, and the newly identified potential therapeutic approaches for, these conditions. This Review summarizes the pathophysiologic and therapeutic overlap between tuberous sclerosis complex and von

Brian J Siroky; Maria F Czyzyk-Krzeska; John J Bissler



Effects of Petroleum Ether Extract of Amorphophallus paeoniifolius Tuber on Central Nervous System in Mice  

PubMed Central

The central nervous system activity of the petroleum ether extract of Amorphophallus paeoniifolius tuber was examined in mice, fed normal as well as healthy conditions. The petroleum ether extract of Amorphophallus paeoniifolius tuber at the doses of 100, 300 and 1000 mg/kg showed significant central nervous system activity in mice. PMID:20376218

Das, S. S.; Sen, Malini; Dey, Y. N.; De, S.; Ghosh, A. K.



Effects of Petroleum Ether Extract of Amorphophallus paeoniifolius Tuber on Central Nervous System in Mice.  


The central nervous system activity of the petroleum ether extract of Amorphophallus paeoniifolius tuber was examined in mice, fed normal as well as healthy conditions. The petroleum ether extract of Amorphophallus paeoniifolius tuber at the doses of 100, 300 and 1000 mg/kg showed significant central nervous system activity in mice. PMID:20376218

Das, S S; Sen, Malini; Dey, Y N; De, S; Ghosh, A K



Patatin and four serine proteinase inhibitor genes are differentially expressed during potato tuber development.  


A highly efficient and synchronous in vitro tuberization system is described. One-node stem pieces from potato (Solanum tuberosum cv. Bintje) plants grown under short day-light conditions containing an axillary bud were cultured in the dark on a tuber-inducing medium. After 5 or 6 days all axillary buds started to develop tubers. To study gene expression during tuber development, RNA isolated from tuberizing axillary buds was used for both in vitro translation and northern blot hybridizations. The genes encoding the proteinase inhibitors I and II (PI-I and PI-II), a Kunitz- and a Bowman-Birk-type proteinase inhibitor were already expressed in uninduced axillary buds. The length of the day-light conditions differently influenced the expression level of the individual genes. In addition, the expression of each of these genes changed specifically during the development of the axillary bud to tuber. In contrast to the expression of these proteinase inhibitor genes, patatin gene expression was only detectable from the day tuberization was manifested as a radial expansion of the axillary bud. These results are discussed with respect to the regulation of the expression of the genes studied in relation to the regulation of tuber development. PMID:1715784

Hendriks, T; Vreugdenhil, D; Stiekema, W J




Technology Transfer Automated Retrieval System (TEKTRAN)

At harvest and for an indeterminate period thereafter, potato tubers will not sprout and are physiologically dormant. Although the underlying molecular mechanisms controlling tuber dormancy are poorly understood, it has been proposed that endogenous plant hormones are intricately involved in potato ...


MR Findings in Tuberous Sclerosis Complex and Correlation with Seizure Development and Mental Impairment  

Microsoft Academic Search

PURPOSE: To correlate the findings on MR scans of the brain in patients with tuberous sclerosis complex with mental disability and the type and age at onset of the first seizure. METHODS: Patients with tuberous sclerosis complex who had MR brain scans were identified. The diagnosis was confirmed, and the clinical information on each patient was updated. The number, site,

Charles W. Shepherd; O. Wayne Houser; Manuel R. Gomez


Photosynthetic assimilation of ¹?C into amino acids in potato (Solanum tuberosum) and asparagine in the tubers.  


Asparagine is the predominant free amino acid in potato tubers and the present study aimed to establish whether it is imported from the leaves or synthesised in situ. Free amino acid concentrations are important quality determinants for potato tubers because they react with reducing sugars at high temperatures in the Maillard reaction. This reaction produces melanoidin pigments and a host of aroma and flavour volatiles, but if free asparagine participates in the final stages, it results in the production of acrylamide, an undesirable contaminant. ¹?CO? was supplied to a leaf or leaves of potato plants (cv. Saturna) in the light and radioactivity incorporated into amino acids was determined in the leaves, stems, stolons and tubers. Radioactivity was found in free amino acids, including asparagine, in all tissues, but the amount incorporated in asparagine transported to the tubers and stolons was much less than that in glutamate, glutamine, serine and alanine. The study showed that free asparagine does not play an important role in the transport of nitrogen from leaf to tuber in potato, and that the high concentrations of free asparagine that accumulate in potato tubers arise from synthesis in situ. This indicates that genetic interventions to reduce free asparagine concentration in potato tubers will have to target asparagine metabolism in the tuber. PMID:24126722

Muttucumaru, Nira; Keys, Alfred J; Parry, Martin A J; Powers, Stephen J; Halford, Nigel G



Effect of antiviral genetical modification on softening of potato tubers during cooking  

Microsoft Academic Search

An investigation into the influence of genetical modification on potato tubers should include also an estimation of their technological usability. Potato tubers of 15 clones of cultivar Irga transformed with viral genome sequences in order to improve their resistance to a necrotic strain of potato virus Y (PVYN) were examined. The effect of cooking on tissue texture, expressed by fracture

Jadwiga Sadowska; Josef Vacek; Józef Fornal; W?odzimierz Zagórski-Ostoja



Distribution of Potato virus Y strains in tubers during the post-harvest period  

Technology Transfer Automated Retrieval System (TEKTRAN)

PVYO, PVYN:O, and PVYNTN infected tubers from Russet Burbank, Russet Norkotah, and Shepody were tested following storage, at the initiation of sprouting and then again at seventy eight days later. Samples were taken from eyes in the stem, middle, and bud (distal end) areas of the tubers. Testing ...


Epitope mapping for monoclonal antibodies recognizing tuber necrotic isolates of Potato virus Y  

Technology Transfer Automated Retrieval System (TEKTRAN)

Potato virus Y (PVY) is an important viral pathogen of potato responsible for reducing tuber yield and quality across the globe. The PVYN and PVYNTN strains, the latter of which induces potato tuber necrotic ringspot disease (PTNRD), are regulated for international potato trade, and have been routin...


Fusarium spp. causing dry rot of seed potato tubers in Michigan and their sensitivity to fungicides  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fusarium dry rot of potato (Solanum tuberosum L.) is a postharvest disease that can be caused by several Fusarium spp. A survey was conducted to establish the composition of Fusarium species causing dry rot of seed tubers in Michigan. A total of 370 dry rot symptomatic tubers were collected in 2009 ...


Effect of Melatonin Dosage on Sleep Disorder in Tuberous Sclerosis Complex  

Microsoft Academic Search

We report a randomized, double-blind, controlled, crossover trial investigating the response to oral melatonin using two dose regimens in patients with sleep disorders associated with tuberous sclerosis complex. Eight outpatients with tuberous sclerosis complex and sleep disorder received either 5 or 10 mg of melatonin. Sleep latency, total sleep time, number of awakenings, and seizure frequency were recorded in sleep

Eleanor Hancock; Finbar OCallaghan; John P. Osborne



Genetic Consequences of Tuber Versus Seed Sampling in Two Wild Potato Species Indigenous to the USA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wild potatoes reproduce in the wild (in situ) clonally by tubers or sexually by seeds. This study used model populations to assess the genetic consequences of sampling in situ tubers or in situ seeds for two indigenous potato species of the USA, Solanum stoloniferum PI 564039 (sto) and Solanum james...


Color Me Safe Coloring Book  


... Me Safe is a coloring book designed for children ages four to seven. Throughout the book, the Safe Family takes simple steps to prevent injuries, such as installing smoke alarms and using child safety seats. Children can have fun coloring the pictures and reading ...


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

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Characterization of Maize Amylose-Extender (ae) Mutant Starches. Part I: Relationship Between Resistant Starch Contents and Molecular Structures  

Technology Transfer Automated Retrieval System (TEKTRAN)

Endosperm starches were isolated from kernels of seven maize amylose-extender (ae) lines. The resistant starch (RS) contents, measured using AOAC method 991.43, showed that three new ae-mutant starch lines developed by the USDA-ARS Germplasm Enhancement (GEM) and Truman State University had larger R...


Structural characteristics of slowly digestible starch and resistant starch isolated from heat-moisture treated waxy potato starch.  


The objective of this study was to investigate the structural characteristics of slowly digestible starch (SDS) and resistant starch (RS) fractions isolated from heat-moisture treated waxy potato starch. The waxy potato starch with 25.7% moisture content was heated at 120°C for 5.3h. Scanning electron micrographs of the cross sections of RS and SDS+RS fractions revealed a growth ring structure. The branch chain-length distribution of debranched amylopectin from the RS fraction had a higher proportion of long chains (DP?37) than the SDS+RS fraction. The X-ray diffraction intensities of RS and SDS+RS fractions were increased compared to the control. The SDS+RS fraction showed a lower gelatinization enthalpy than the control while the RS fraction had a higher value than the SDS+RS fraction. In this study we showed the RS fraction is composed mainly of crystalline structure and the SDS fraction consists of weak crystallites and amorphous regions. PMID:25857975

Lee, Chang Joo; Moon, Tae Wha



A role for symplastic gating in the control of the potato tuber life cycle  

PubMed Central

The control of the potato tuber life cycle has been the subject of significant interest over many years. A number of different approaches have been adopted and data is available regarding hormonal, metabolic and gene expression changes that occur over the tuber life cycle. Despite this intense effort, no unifying model for the control of the potato tuber life cycle has emerged. We have undertaken a detailed analysis of the tuber life cycle utilising physiological, biochemical and cell-biological techniques. It has emerged that a major factor contributing to both tuber induction and dormancy break is symplastic gating which controls the allocation of resources to meristematic or vegetative tissues. Future challenges include the determination of factors regulating symplastic gating at the molecular level and the extrapolation of these findings to other systems. PMID:19704762

Roberts, Alison G; Viola, Roberto



Frost-susceptible protein in plasma membranes in tubers of Helianthus tuberosus L.  


When plasma membranes were prepared from tubers of Helianthus tuberosus L. (Jerusalem artichoke) frozen at a sublethal temperature (-10 degrees C), the levels of some plasma membrane proteins, named frost-susceptible proteins (FSPs), decreased [Uemura, M., et al., Plant Physiol., 80, 187-195 (1986)]. The aim of this study was to characterize the response of FSP120, which is named FSP-3 in a previous report, to freezing treatment by immunoblotting. Levels of FSP120 in the plasma membranes of tubers decreased after sublethal freezing, whereas no degraded products were detected in the microsomes or the soluble fraction. The amount of FSP120 in the crude extract of frozen tubers remained at a comparable level to that of the unfrozen tubers. These results suggest that FSP120 might be released from plasma membranes during freezing treatment of the tubers of Jerusalem artichoke. PMID:14745181

Arakawa, Keita; Hanazaki, Mitsuru; Yoshida, Shizuo



Can loss of apical dominance in potato tuber serve as a marker of physiological age?  

PubMed Central

The potato tuber constitutes a model system for the study of dormancy release and sprouting, suggested to be regulated by endogenous plant hormones and their balance inside the tuber. During dormancy, potato tubers cannot be induced to sprout without some form of stress or exogenous hormone treatment. When dormancy is released, sprouting of the apical bud may be inhibited by sprout control agents or cold temperature. Dominance of the growing apical bud over other lateral buds decreases during storage and is one of the earliest morphophysiological indicators of the tuber's physiological age. Three main types of loss of apical dominance (AD) affect sprouting shape. Hallmarks of programmed cell death (PCD) have been identified in the tuber apical bud meristem (TAB-meristem) during normal growth, and are more extensive when AD is lost following extended cold storage or chemical stress. Nevertheless, the role of hormonal regulation in TAB-meristem PCD remains unclear. PMID:22899056

Eshel, Dani; Teper-Bamnolker, Paula



Refractive Errors and Strabismus in Children With Tuberous Sclerosis: A Controlled Study  

PubMed Central

Purpose To evaluate the prevalence of refractive errors and strabismus in children with tuberous sclerosis and in control subjects. Methods Twenty-three children with tuberous sclerosis and 151 control subjects were evaluated. All children underwent cycloplegic autorefraction or retinoscopy, slit-lamp biomicroscopy, and dilated fundus examination. Ocular alignment was assessed by the Hirschberg, Krimsky, or prism cover test. Results The total prevalence of hypermetropia and amblyopia was significantly higher in patients with tuberous sclerosis (p = .035) than in the control subjects (p = .002). Conclusion A high prevalence of hypermetropia seems to be an additional feature of tuberous sclerosis. Early screening for this amblyogenic factor is indicated in patients with tuberous sclerosis. PMID:19928739

Akinci, Arsen; Oner, Ozgur; Guven, Alev; Degerliyurt, Aydan; Munir, Kerim



Color Sudoku  

NSDL National Science Digital Library

The popular sudoku puzzles use numbers, but the game could played with any set of 9 different objects! In this activity (on pages 56-75 of PDF), learners use objects of different colors (marbles, paper squares, candies) to solve sudoku puzzles. Learners use logic to determine where all the colored objects go, given the different colors already present on the puzzles. The activity includes suggestions for how to approach the game, 10 puzzles of varying size and difficulty, and links to websites with many more puzzles.



Color Theory  

NSDL National Science Digital Library

This Web site, developed by the Exploratories Project at Brown University, provides a series of applets to help users understand the various concepts in Color Theory. In the combined Color Mixing applet, undergraduate and high school students can discover how lights, paints, and filters interact. Users can learn about the properties of incoming light, frequency, and reflectance. The site also provides activities for metamers, Triple Cell Response, and much more. Anyone seeking help with color concepts will benefit from this educational, interactive Web site.


Development and Characterization of Spaghetti with High Resistant Starch Content Supplemented with Banana Starch  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pasta products, such as spaghetti, are relatively healthy foods traditionally manufactured from durum wheat semolina and water. Nutritionally improved spaghetti products with additional health benefits can be produced by supplementing durum wheat with suitable food additives, such as banana starch....


Production of volatile organic compounds (VOCs) by yeasts isolated from the ascocarps of black ( Tuber melanosporum Vitt.) and white ( Tuber magnatum Pico) truffles  

Microsoft Academic Search

Twenty-nine yeast strains were isolated from the ascocarps of black and white truffles (Tuber\\u000a melanosporum Vitt. and Tuber\\u000a magnatum Pico, respectively), and identified using a polyphasic approach. According to the conventional taxonomic methods, MSP-PCR\\u000a fingerprinting and sequencing of the D1\\/D2 domain of 26S rDNA, the strains were identified as Candida saitoana, Debaryomyces hansenii, Cryptococcus sp., Rhodotorula mucilaginosa, and Trichosporon moniliiforme.

Pietro Buzzini; Chiara Gasparetti; Benedetta Turchetti; Maria Rita Cramarossa; Ann Vaughan-Martini; Alessandro Martini; Ugo Maria Pagnoni; Luca Forti



Edible canna ( Canna edulis) as a complementary starch source to cassava for the starch industry  

Microsoft Academic Search

Edible canna (Canna edulis Ker) as an alternative starch source was evaluated on the basis of genetic characteristics, agronomic traits and starch properties. Four canna varieties indigenous to Thailand were examined including Thai-green, Japanese-green, Thai-purple and Chinese-purple and compared with cassava (Manihot esculenta Crantz). Using the Random Amplified Polymorphic DNA (RAPD) technique employing ten 10-base primers, four primers implied that

Kuakoon Piyachomkwan; Sunee Chotineeranat; Chukiet Kijkhunasatian; Ratchata Tonwitowat; Siripatr Prammanee; Christopher G Oates; Klanarong Sriroth



Impact of the addition of resistant starch from modified pea starch on dough and bread performance  

Microsoft Academic Search

The interest in the use of resistant starch (RS) for the development of new bakery products has significantly increased due\\u000a to its ascribed physiological effects with proven health benefits. The objective of the present work was to analyse the effects\\u000a of the wheat flour substitution by modified pea starch with high level of RS (PeaP) on breadmaking performance. The effects

Juan Mario Sanz-Penella; Ma?gorzata Wronkowska; Maria Soral-?mietana; Concha Collar; Monika Haros



Evaluation of a High Throughput Starch Analysis Optimised for Wood  

PubMed Central

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

Bellasio, Chandra; Fini, Alessio; Ferrini, Francesco



Resistant Starch: Promise for Improving Human Health12  

PubMed Central

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

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.



Novel products from starch based feedstocks  

Technology Transfer Automated Retrieval System (TEKTRAN)

There has been progress in the utilization of starch as a partial replacement for petroleum based plastics, but it remains a poor direct substitute for plastics, and a moderate one for composites. Our research focuses on using polymers produced from direct fermentation such as poly(lactic acid) or m...


Starch-lipid composites containing cimmamaldehyde  

Technology Transfer Automated Retrieval System (TEKTRAN)

The formulation of a starch-lipid composite containing cinnamaldehyde as antimicrobial agent has been studied. Cinnamaldehyde was incorporated as an emulsion using Acetem 90-50K as a carrier and Tween 60 as the emulsifier. Oil in water emulsions were prepared by direct emulsification using a high sh...


Resistant starch in food: a review.  


The nutritional property of starch is related to its rate and extent of digestion and absorption in the small intestine. For nutritional purposes, starch is classified as rapidly available, slowly available and resistant starch (RS). The exact underlying mechanism of relative resistance of starch granules is complicated because those factors are often interconnected. The content of RS in food is highly influenced by food preparation manner and processing techniques. Physical or chemical treatments also alter the level of RS in a food. Commercial preparations of RS are now available and can be added to foods as an ingredient for lowering the calorific value and improving textural and organoleptic characteristics along with increasing the amount of dietary fiber. RS has assumed great importance owing to its unique functional properties and health benefits. The beneficial effects of RS include glycemic control and control of fasting plasma triglyceride and cholesterol levels and absorption of minerals. This review attempts to analyze the information published, especially in the recent past, on classification, structure, properties, applications and health benefits of RS. © 2014 Society of Chemical Industry. PMID:25331334

Raigond, Pinky; Ezekiel, Rajarathnam; Raigond, Baswaraj




EPA Science Inventory

While potato starch has been an item of commerce for many years, traditional processing methods have incurred large volumes of high BOD effluents. The research summarized by this report has lead to a modified process which upgrades the soluble components formerly discarded in the...


Reactions of Starch in Ionic Liquids  

Technology Transfer Automated Retrieval System (TEKTRAN)

We found that starches are found to be soluble at 80 ºC in ionic liquids such as 1-butyl-3-methylimidazolium chloride (BMIMCl) and 1-butyl-3-methylimidazolium dicyanamide (BMIMdca) in concentration up to 10% (w/w). Higher concentrations of biopolymers in these novel solvents resulted in solutions w...


Colorful Electrophoresis  

NSDL National Science Digital Library

In this activity, learners follow step-by-step instructions to build a gel electrophoresis chamber using inexpensive materials from local hardware and electronic stores. Then, learners follow instructions to simulate DNA electrophoresis using food colors from the kitchen pantry.



Drying and cracking mechanisms in a starch slurry  

NASA Astrophysics Data System (ADS)

Starch-water slurries are commonly used to study fracture dynamics. Drying starch cakes benefit from being simple, economical, and reproducible systems, and have been used to model desiccation fracture in soils, thin-film fracture in paint, and columnar joints in lava. In this paper, the physical properties of starch-water mixtures are studied, and used to interpret and develop a multiphase transport model of drying. Starch cakes are observed to have a nonlinear elastic modulus, and a desiccation strain that is comparable to that generated by their maximum achievable capillary pressure. It is shown that a large material porosity is divided between pore spaces between starch grains, and pores within starch grains. This division of pore space leads to two distinct drying regimes, controlled by liquid and vapor transport of water, respectively. The relatively unique ability for drying starch to generate columnar fracture patterns is shown to be linked to the unusually strong separation of these two transport mechanisms.

Goehring, Lucas



Finding Colors  

NSDL National Science Digital Library

In this chemistry challenge, learners combine acids and bases in a universal indicator to create five different colors. Using vinegar, washing soda, and Bogen universal indicator, the goal is to find combinations that create red, orange, yellow, green, and blue solutions. Background information explains a little about how acids and bases interact to affect the pH of a solution, and how the indicator changes color based on the pH. Safety notes are included.




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


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

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



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

PubMed Central

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

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



C-type starch from high-amylose rice resistant starch granules modified by antisense RNA inhibition of starch branching enzyme.  


High-amylose starch is a source of resistant starch (RS) which has a great benefit on human health. A transgenic rice line (TRS) enriched amylose and RS had been developed by antisense RNA inhibition of starch branching enzymes. In this study, the native starch granules were isolated from TRS grains as well as the wild type, and their crystalline type was carefully investigated before and after acid hydrolysis. In high-amylose TRS rice, the C-type starch, which might result from the combination of both A-type and B-type starch, was observed and subsequently confirmed by multiple physical techniques, including X-ray powder diffraction, solid-state nuclear magnetic resonance, and Fourier transform infrared. Moreover, the change of starch crystalline structure from C- to B-type during acid hydrolysis was also observed in this RS-rich rice. These data could add to our understanding of not only the polymorph structure of cereal starch but also why high-amylose starch is more resistant to digestion. PMID:20499916

Wei, Cunxu; Xu, Bin; Qin, Fengling; Yu, Huaguang; Chen, Chong; Meng, Xianglen; Zhu, Lijia; Wang, Youping; Gu, Minghong; Liu, Qiaoquan



Clobazam therapy of refractory epilepsy in tuberous sclerosis complex.  


Clobazam (CLB) was recently approved by the FDA, but has not been evaluated in tuberous sclerosis complex (TSC). We retrospectively reviewed a cohort of patients with TSC and refractory epilepsy who started CLB over a 5-year period. Clinical characteristics and number of tubers on MRI were assessed. Duration of therapy, therapeutic response and adverse events were recorded. CLB was prescribed in 29 adults and children of whom 72% were cognitively impaired, with a median age at seizure onset of 5 months. Mean duration of CLB therapy was 17.3 months with a 12 and 24-month estimated retention rate of 82% and 68%, respectively. Twenty patients (69%) reported a good response (>50% seizure reduction) at the end of the titration, and six patients (21%) remained good responders after 12 months of CLB therapy. Adverse events occurred in 13 patients, predominantly somnolence and behavioral disorders. One quarter of the responders reported improvement in behavior. No predictive factor for a good response could be identified. CLB appears to be a well-tolerated and valuable option for treatment of refractory epilepsy in TSC. PMID:23219029

Jennesson, Melanie; van Eeghen, Agnies M; Caruso, Paul A; Paolini, Jan L; Thiele, Elizabeth A



Feasibility of enzymatic hydrolysis and alcoholic fermentation of starch contained in buffalo gourd (Cucurbita foetidissima) roots  

SciTech Connect

The suitability of using annually grown, carrot-sized buffalo gourd (Cucurbita foetidissima) roots as a feedstock for alcoholic fermentation was explored. Roots grown in 1982 and 1983 were slurried, dextrinized and saccharified using Takatherm and Diazyme (commercial enzymes manufactured by Miles Laboratories), and fermented by the action of Saccharomyces cerevisiae. These processes were monitored in detail and results were compared with those displayed by controls formulated using potato tubers. The preparation of gourd root slurries with suitable viscosity characteristics for enzymatic digestion required the addition of water (at least 50% by weight) which reduced the proportion of fermentable sugars in the resulting saccharified suspensions. The resulting slurries were well-suited to enzymatic conversion of starch to sugar. Estimates of enzymatic efficiency in gourd root suspensions did not suggest the presence of naturally occurring amylase or glucosidase inhibitors in these plant materials. Saccharified gourd root mashes supported yeast growth well and produced ethanol yields at 82.2-86.5% of the theoretically maximum efficiency. 23 references.

Scheerens, J.C.; Kopplin, M.J.; Abbas, I.R.; Nelson, J.M.; Gathman, A.C.; Berry, J.W.



A magnetic resonance imaging study of cerebellar volume in tuberous sclerosis complex.  


The cerebellum plays an important role in motor learning and cognition, and structural cerebellar abnormalities have been associated with cognitive impairment. In tuberous sclerosis complex, neurologic outcome is highly variable, and no consistent imaging or pathologic determinant of cognition has been firmly established. The cerebellum calls for specific attention because mouse models of tuberous sclerosis complex have demonstrated a loss of cerebellar Purkinje cells, and cases of human histologic data have demonstrated a similar loss in patients. We hypothesized that there might be a common cerebellar finding in tuberous sclerosis complex that could be measured as morphometric changes with magnetic resonance imaging. Using a robust, automated image analysis procedure, we studied 36 patients with tuberous sclerosis complex and age-matched control subjects and observed significant volume loss among patients in the cerebellar cortices and vermis. Furthermore, this effect was strongest in a subgroup of 19 patients with a known, pathogenic mutation of the tuberous sclerosis 2 gene and impacted all cerebellar structures. We conclude that patients with tuberous sclerosis complex exhibit volume loss in the cerebellum, and this loss is larger and more widespread in patients with a tuberous sclerosis 2 mutation. PMID:23337002

Weisenfeld, Neil I; Peters, Jurriaan M; Tsai, Peter T; Prabhu, Sanjay P; Dies, Kira A; Sahin, Mustafa; Warfield, Simon K



Selected properties of acetylated adipate of retrograded starch.  


Native potato starch (NS) and retrograded starch (R - obtained via freezing and defrosting of a starch paste) were used to prepare starch acetates: NS-A and R-A, and then acetylated distarch adipates: NS-ADA and R-ADA. The chemically-modified preparations produced from retrograded starch (R-A; R-ADA) were characterized by a higher degree of esterification compared to the modified preparations produced under the same conditions from native potato starch (NS-A; NS-ADA). Starch resistance to amylolysis was observed to increase (to 30-40 g/100 g) as a result of starch retrogradation and acetylation. Starch cross-linking had a significant impact on the increased viscosity of the paste in the entire course of pasting characteristics and on the increased values of rheological coefficients determined from the equations describing flow curves. The produced preparation of acetylated retrograded starch cross-linked with adipic acid (R-ADA) may be deemed an RS3/4 preparation to be used as a food thickening agent. PMID:24274559

Zi?ba, T; Gryszkin, A; Kapelko, M



Starch bioengineering affects cereal grain germination and seedling establishment  

PubMed Central

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 ?-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. ?-Amylase activity was distinctly suppressed in both the HP and the AO lines. Pre-germination ?-amylase deposition was low in the AO grains and ?-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

Hebelstrup, Kim H.; Blennow, Andreas



Physicochemical Properties of Canna edulis Ker Starch on Heat-Moisture Treatment  

Microsoft Academic Search

Canna edulis Ker starch was modified by heat-moisture treatment at moisture levels ranging from 18 to 27 g\\/100 g starch and its physicochemical properties were investigated. Amylose content, swelling power, solubility as well as water and oil absorption capacity in native starch were higher than in all treated starches. However, alkaline water retention and acid susceptibility of native starch were

Juan Zhang; Zheng-Wu Wang; Jun-An Yang



Chemical Composition, Mineral Profile, and Functional Properties of Canna ( Canna edulis ) and Arrowroot ( Maranta spp .) Starches  

Microsoft Academic Search

The aim of the present study was to evaluate some chemical and mineral characteristics and functional and rheological properties of Canna and Arrowroot starches produced in the Venezuelan Andes. Canna starch showed a higher (P P H. Both starches show negative syneresis. The apparent viscosity of Canna starch was higher (P < 0.05) than the Arrowroot starch values. The size

Elevina Pérez; Mary Lares



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

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Size controlled synthesis of starch nanoparticles by a simple nanoprecipitation method  

Microsoft Academic Search

Starch nanoparticles of particle size range between 300nm and 400nm were synthesized by a simple nanoprecipitation method from native sago starch (Metroxylon sagu). Starch nanoparticles were formed by controlled precipitation through drop-wise addition of dissolved native starch solution to excess absolute ethanol. The size and shape of starch nanoparticles were modulated varying the synthesis parameters including the use of appropriate

Suk Fun Chin; Suh Cem Pang; Soon Hiang Tay



Effect of temperature on expression of genes encoding enzymes for starch biosynthesis in developing wheat endosperm  

Microsoft Academic Search

The effect of high temperature on starch accumulation, starch granule populations, and expression of genes encoding key enzymes for starch biosynthesis was examined during grain development in wheat (Triticum aestivum L. cv. Butte 86). High temperature applied from anthesis to maturity reduced the duration of starch accumulation. Starch accumulation ceased approximately 6 days earlier for grain produced under a 37\\/17°C

William J. Hurkman; Kent F. McCue; Susan B. Altenbach; Anna Korn; Charlene K. Tanaka; Kerry M. Kothari; Erika L. Johnson; Donald B. Bechtel; Jeff D. Wilson; Olin D. Anderson; Frances M. DuPont



Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films  

Microsoft Academic Search

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)

Wirongrong Tongdeesoontorn; Lisa J Mauer; Sasitorn Wongruong; Pensiri Sriburi; Pornchai Rachtanapun



Colorful Mathematics  

NSDL National Science Digital Library

Funded by Industry Canada's SchoolNet initiative with the cooperation of the Canadian Mathematical Society, Colorful Mathematics takes a game-oriented approach to teaching K-12 mathematics. The project has developed five coloring games that teach children about problem solving, and pattern identification, which "are all at the very heart of mathematics." The coloring approach makes difficult graph concepts "that are still the subject of active research by mathematicians, computer scientists and industry researchers" more accessible to children. The software program, which is available for free from this website, is set up to check for mistakes and challenge students to improve on their results. A Teacher's Corner section gives an overview of the games, "some sample questions for discussion with the curious student," and an overview of terminology used in the software program. The website is also available in French.


Colorful Waves  

NSDL National Science Digital Library

You're probably really upset that all you have so far is a simple little ray model of light. When do we get to the good stuff, you say? How about now? As a bonus, you get to look at lots of pretty colors. This chapter addresses how light can be modeled as a series of waves. These waves consist of changing electric and magnetic fields that can travel through empty space, as well as through other mediums. Different frequencies of light waves correspond to different colors of light. White light is composed of all the colors of visible light. Visible light is just a small portion of the entire spectrum of electromagnetic waves.

William C. Robertson, Ph.D.



Increasing of Food and Bioenergy Potato Resources by Microbial Influence on Tubers Phytohormonal Status  

NASA Astrophysics Data System (ADS)

Potato and its by-products became a promising both food and bioenergy resource. The determination of the bacteriaantagonists influence on phytohormone status and productivity of potato tubers was studied. The indole-3-acetic acid content during the dormancy end and germinating in the tubers treated with Bacillus subtilis Ch-13 was fewer than in the control samples. L-tryptophan significant quantity compared to the control was found in the treated tubers in a state of physiological dormancy (more than 2-fold) and especially during active germination (43 times greater). Average potato yield increase at treated fields was of 18.8 %.

Kiprushkina, Elena I.; Baranenko, Denis A.



Kool Colors  

NSDL National Science Digital Library

Learners investigate how temperature affects the rate of chemical reactions by observing how steel wool reacts with various types of Kool-Aid solutions at different temperatures. The reaction is monitored as the color fades in the Kool-Aid solutions. Background information includes how the dyes change color from an oxidation-reduction reaction. Extensions include investigating how surface area and concentration affect reaction rate. Part of the "No Hassle Messy Science with a Wow" activity guide by OMSI, where all activities use only household materials.

Oregon Museum of Science and Industry



Computational modeling of biodegradable starch based polymer composites  

NASA Astrophysics Data System (ADS)

Purpose. The goal of this study is to improve the favorable molecular interactions between starch and PPC by addition of grafting monomers MA and ROM as compatibilizers, which would advance the mechanical properties of starch/PPC composites. Methodology. DFT and semi-empirical methods based calculations were performed on three systems: (a) starch/PPC, (b) starch/PPC-MA, and (c) starch-ROM/PPC. Theoretical computations involved the determination of optimal geometries, binding-energies and vibrational frequencies of the blended polymers. Findings. Calculations performed on five starch/PPC composites revealed hydrogen bond formation as the driving force behind stable composite formation, also confirmed by the negative relative energies of the composites indicating the existence of binding forces between the constituent co-polymers. The interaction between starch and PPC is also confirmed by the computed decrease in stretching CO and OH group frequencies participating in hydrogen bond formation, which agree qualitatively with the experimental values. A three-step mechanism of grafting MA on PPC was proposed to improve the compatibility of PPC with starch. Nine types of 'blends' produced by covalent bond formation between starch and MA-grafted PPC were found to be energetically stable, with blends involving MA grafted at the 'B' and 'C' positions of PPC indicating a binding-energy increase of 6.8 and 6.2 kcal/mol, respectively, as compared to the non-grafted starch/PPC composites. A similar increase in binding-energies was also observed for three types of 'composites' formed by hydrogen bond formation between starch and MA-grafted PPC. Next, grafting of ROM on starch and subsequent blend formation with PPC was studied. All four types of blends formed by the reaction of ROM-grafted starch with PPC were found to be more energetically stable as compared to the starch/PPC composite and starch/PPC-MA composites and blends. A blend of PPC and ROM grafted at the ' á ' position on amylose exhibited a maximal increase of 17.1 kcal/mol as compared with the starch/PPC-MA blend. Conclusions. ROM was found to be a more effective compatibilizer in improving the favorable interactions between starch and PPC as compared to MA. The ' á ' position was found to be the most favorable attachment point of ROM to amylose for stable blend formation with PPC.

Joshi, Sachin Sudhakar



Processing of porous ceramics by ‘starch consolidation’  

Microsoft Academic Search

A new consolidation method for forming porous ceramics was developed using starch as both consolidator\\/binder and pore former. Simple and complex-shaped components of porous alumina were shaped and demoulded in wet state. After drying, burn-out and sintering, materials with ultimate porosities between 23 and 70% were obtained. The overall pore structures were dominated by the large spherically shaped pores (10–80

O. Lyckfeldt; J. M. F. Ferreira



Peculiarities of aqueous amaranth starch suspensions.  


Among the starches the granules from amaranth starch (a. hypochondriacus, amylopectin type) are singular because of their extremely small size of 1-3 microm and high uniformity. However, large spherical particles of 30-80 microm in diameter were observed from spray-dried amaranth starch by environmental scanning electron microscopy (ESEM) which exhibited a characteristic fine structure. After the mixture was stirred in cold water, the large particles disintegrate into small ones of 1-3 microm diameter. The particles from the stirred suspension were characterized by static and dynamic light scattering and viscometry. Almost the same diameters were found by the three techniques which were 1.76 times larger than those for the dry starch particles investigated by ESEM. The difference in size is explained by reversible uptake of water. A molar mass of M(w,granule) = 177 x 10(9) g/mol was measured for the granular particle. After dissolution in 0.5 N sodium hydroxide a molar mass M(w,amylopectin) = 104 x 10(6) g/mol of the amylopectin was obtained that agreed satisfactorily with that of waxy maize. Thus the granule consists on average of 1700 amylopectin molecules. Furthermore, rheological measurements were carried out with aqueous suspensions at room temperature. A shear gradient dependence was found for concentrations higher than 6% (w/v) of granules. At c > 19% reversible gel formation was observed with G'(omega) > G"(omega) and a plateau over 2 decades. The zero shear viscosity as a function of c[eta] shows behavior similar to glycogen and to latex particles. The granules, however, differ from common latex particles because of their capability to gel formation. PMID:11790134

Wilhelm, Eckart; Aberle, Thomas; Burchard, Walther; Landers, Rüdiger



Development of highly-transparent protein/starch-based bioplastics.  


Striving to achieve cost-competitive biomass-derived materials for the plastics industry, the incorporation of starch (corn and potato) to a base formulation of albumen and glycerol was considered. To study the effects of formulation and processing, albumen/starch-based bioplastics containing 0-30 wt.% starch were prepared by thermo-plastic and thermo-mechanical processing. Transmittance measurements, DSC, DMTA and tensile tests were performed on the resulting bioplastics. Optical and tensile properties were strongly affected by starch concentration. However, DMTA at low deformation proved to be insensitive to starch addition. Thermo-mechanical processing led to transparent albumen/starch materials with values of strength at low deformation comparable to commodity plastics. Consequently, albumen biopolymers may become a biodegradable alternative to oil-derived plastics for manufacturing transparent packaging and other plastic stuffs. PMID:19900806

Gonzalez-Gutierrez, J; Partal, P; Garcia-Morales, M; Gallegos, C



Soybean cotyledon starch metabolism is sensitive to altered gravity conditions  

NASA Technical Reports Server (NTRS)

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.

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



Examining Colors, Color Perception, and Sight  

NSDL National Science Digital Library

Students of all ages are fascinated by color and how we perceive it. For the main activity in this chapter, your class explores colors and visual perception by mixing colors in several ways. Students learn more about colors, light, vision, and color compo

John Eichinger



Colorful Accounting  

ERIC Educational Resources Information Center

As instructors of accounting, we should take an abstract topic (at least to most students) and connect it to content known by students to help increase the effectiveness of our instruction. In a recent semester, ordinary items such as colors, a basketball, and baseball were used to relate the subject of accounting. The accounting topics of account…

Warrick, C. Shane



Enzymatic transformation of nonfood biomass to starch.  


The global demand for food could double in another 40 y owing to growth in the population and food consumption per capita. To meet the world's future food and sustainability needs for biofuels and renewable materials, the production of starch-rich cereals and cellulose-rich bioenergy plants must grow substantially while minimizing agriculture's environmental footprint and conserving biodiversity. Here we demonstrate one-pot enzymatic conversion of pretreated biomass to starch through a nonnatural synthetic enzymatic pathway composed of endoglucanase, cellobiohydrolyase, cellobiose phosphorylase, and alpha-glucan phosphorylase originating from bacterial, fungal, and plant sources. A special polypeptide cap in potato alpha-glucan phosphorylase was essential to push a partially hydrolyzed intermediate of cellulose forward to the synthesis of amylose. Up to 30% of the anhydroglucose units in cellulose were converted to starch; the remaining cellulose was hydrolyzed to glucose suitable for ethanol production by yeast in the same bioreactor. Next-generation biorefineries based on simultaneous enzymatic biotransformation and microbial fermentation could address the food, biofuels, and environment trilemma. PMID:23589840

You, Chun; Chen, Hongge; Myung, Suwan; Sathitsuksanoh, Noppadon; Ma, Hui; Zhang, Xiao-Zhou; Li, Jianyong; Zhang, Y-H Percival



Starch composites reinforced by bamboo cellulosic crystals.  


Using a method of combined HNO(3)-KClO(3) treatment and sulfuric acid hydrolysis, bamboo cellulose crystals (BCCs) were prepared and used to reinforce glycerol plasticized starch. The structure and morphology of BCCs were investigated using X-ray diffraction, electron microscopy, and solid-state (13)C NMR. Results showed that BCCs were of typical cellulose I structure, and the morphology was dependent on its concentration in the suspension. BCC of 50-100 nm were assembled into leaf nervations at low concentration (i.e. 0.1 wt.% of solids), but congregated into a micro-sized "flower" geometry at high concentration (i.e. 10.0 wt.% of solids). Tensile strength and Young's modulus of the starch/BCC composite films (SBC) were enhanced by the incorporation of the crystals due to reinforcement of BCCs and reduction of water uptake. BCCs at the optimal 8% loading level exhibited a higher reinforcing efficiency for plasticized starch plastic than any other loading level. PMID:20015636

Liu, Dagang; Zhong, Tuhua; Chang, Peter R; Li, Kaifu; Wu, Qinglin



Enzymatic transformation of nonfood biomass to starch  

PubMed Central

The global demand for food could double in another 40 y owing to growth in the population and food consumption per capita. To meet the world’s future food and sustainability needs for biofuels and renewable materials, the production of starch-rich cereals and cellulose-rich bioenergy plants must grow substantially while minimizing agriculture’s environmental footprint and conserving biodiversity. Here we demonstrate one-pot enzymatic conversion of pretreated biomass to starch through a nonnatural synthetic enzymatic pathway composed of endoglucanase, cellobiohydrolyase, cellobiose phosphorylase, and alpha-glucan phosphorylase originating from bacterial, fungal, and plant sources. A special polypeptide cap in potato alpha-glucan phosphorylase was essential to push a partially hydrolyzed intermediate of cellulose forward to the synthesis of amylose. Up to 30% of the anhydroglucose units in cellulose were converted to starch; the remaining cellulose was hydrolyzed to glucose suitable for ethanol production by yeast in the same bioreactor. Next-generation biorefineries based on simultaneous enzymatic biotransformation and microbial fermentation could address the food, biofuels, and environment trilemma. PMID:23589840

You, Chun; Chen, Hongge; Myung, Suwan; Sathitsuksanoh, Noppadon; Ma, Hui; Zhang, Xiao-Zhou; Li, Jianyong; Zhang, Y.-H. Percival



Silicon tetrachloride plasma induced grafting for starch-based composites  

Microsoft Academic Search

Non-modified virgin starch is seldom used directly in industrial applications. Instead, it is often physically and\\/or chemically modified to achieve certain enhanced properties. For many of the non-food applications, these modifications involve changing its hydrophilicity to create hydrophobic starch. In this study, the hydrophobic starch was produced through silicon tetrachloride (SiCl4) plasma induced graft polymerization, so that it could be

Yonghui C. Ma



Physical properties of starch nanocrystal-reinforced pullulan films  

Microsoft Academic Search

Nanocomposite materials were prepared using sorbitol-plasticized pullulan as the amorphous matrix and an aqueous suspension of starch nanocrystals (prepared by submitting native granules from waxy maize starch to acid hydrolysis at 35°C) as the reinforcing phase. Wide-angle X-ray diffraction analysis showed an increase of the crystallinity of the composite biopolymer films with increasing of starch nanocrystal content. The water absorption

Eleana Kristo; Costas G. Biliaderis



Stress relaxation of starch\\/synthetic polymer blends  

Microsoft Academic Search

Stress relaxation behaviour of injection-moulded starch\\/synthetic polymer blends were studied. In one experiment, the starch content was kept constant at 70% while the amylose to amylopectin ratio was varied. The synthetic polymers in the blend included high-density (HPDE) and low-density polyethylene (LPDE), and ethylene vinyl acetate (EVA). In the second experiment, the starch content in the blend was varied. A

M. Bhattacharya



Physicochemical studies of starch from foxtail millet ( Setaria italica Beauv.)  

Microsoft Academic Search

Properties of starch granules prepared from 53 varieties of foxtail millet were examined by scanning electron microscopy, amperometric iodine titrimetry and differential scanning calorimetry. The granular size of the starches ranged from 6.8 to 11.8 ?m in diameter on average. The wavelength at maximum absorption (?max) for iodine-starch complexes ranged from 579 to 600 nm and blue values (absorbance at

S Fujita; Y Sugimoto; Y Yamashita; H Fuwa



Structure characterization and hypoglycemic effects of dual modified resistant starch from indica rice starch.  


Hypoglycemic effects of indica rice resistant starch (IR-RS) were investigated. We prepared IR-RS using a method that combined physical modification and enzyme modification, and the RS content was 47.0%. Differential scanning calorimetry--thermal gravimetric analysis showed that IR-RS have higher enthalpy and less loss of mass than single modified RS, heat-moisture RS and native starch. Scanning electron microscopy revealed that IR-RS displayed more compact spatial structure. IR-RS products displayed a mixture of B-and V-type x-ray diffraction patterns and the cyrstallinity was 51.0%. IR-RS significantly affected body weight, blood glucose, organ indices and serum lipid levels. These results demonstrated that dual modification changed the structure of indica rice starch and affected its digestibility as well as the blood glucose levels of the diabetic mice who consumed it. PMID:24528703

Zhou, Ying; Meng, Shaohua; Chen, Deyi; Zhu, Xiping; Yuan, Huaibo



Linkage studies in Israeli families with tuberous sclerosis  

SciTech Connect

Tuberous sclerosis complex (TSC) is a clinically distinctive autosomal dominant disorder with a population frequency of 1 in 10,000. It affects numerous body systems including skin, brain and kidney, but the etiology is unknown. Linkage studies have indicated genetic heterogeneity. Although about 2/3 of the TSC families in the U.S.A. are linked to markers on chromosome 16p, most TSC families in England are linked to 9q. Therefore, we studied 8 Israeli families with TSC: three showed evidence of linkage to chromosome 16 and two to chromosome 9. In the remaining 3 small families, we were unable to determine linkage due to lack of recombination in both loci. No phenotype/genotype correlation was found, and there was no ethnic predilaction. It seems that in the Israeli Jewish population, TSC is more frequently linked to chromosome 16q.

Ofir, H.; Magal, N.; Kivity, S. [and others



Assessment of ectomycorrhizal biodiversity in Tuber macrosporum productive sites.  


Tuber macrosporum Vittad. is a truffle with superb organoleptic properties, whose cultivation is still in its infancy. For the first time we have aimed to provide information on ectomycorrhizal communities in natural and cultivated T. macrosporum sites. Ectomycorrhizal morphotypes were identified using ITS nrDNA sequencing and sorted into molecular operational taxonomic unit (MOTU). We detected 16 MOTUs in the T. macrosporum cultivated plantation. Ascomycota were the most abundant (86.4%) with Helvellaceae, Pyronemataceae and Pezizaceae the most common. Twenty-two MOTUs were collected in the natural T. macrosporum site. Basidiomycota morphotypes were plentiful (70.6%) and Thelephoraceae dominated. Each site had different taxa belowground with only T. macrosporum in common, being more abundant in the natural (18.2%) than in the cultivated (14.4%) site. Species richness, Simpson and Shannon diversity indices, taxonomic diversity, distinctness and variation of taxonomic distinctness were lower in the cultivated than in the natural site. PMID:24232503

Benucci, Gian Maria Niccolò; Raggi, Lorenzo; Albertini, Emidio; Csorbai, Andrea Gógán; Donnini, Domizia



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

Code of Federal Regulations, 2011 CFR

...true Applicability; description of the wheat starch and gluten subcategory. 406...STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory....



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

Code of Federal Regulations, 2012 CFR

...false Applicability; description of the wheat starch and gluten subcategory. 406...STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory....



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

Code of Federal Regulations, 2014 CFR

...true Applicability; description of the wheat starch and gluten subcategory. 406...STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory....



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

Code of Federal Regulations, 2013 CFR

...true Applicability; description of the wheat starch and gluten subcategory. 406...STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100 Applicability; description of the wheat starch and gluten subcategory....



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

Code of Federal Regulations, 2010 CFR

...Applicability; description of the wheat starch and gluten subcategory. 406.100...MILLS POINT SOURCE CATEGORY Wheat Starch and Gluten Subcategory § 406.100...Applicability; description of the wheat starch and gluten subcategory. The...



Effect of acetylation, oxidation and annealing on physicochemical properties of bean starch.  


Black and Pinto bean starches were physically and chemically modified to investigate the effect of modification on digestibility and physicochemical properties of bean starch. The impact of acetylation, oxidation (ozonation) and annealing on the chemical composition, syneresis, swelling volume, pasting, thermal properties and digestibility of starches was evaluated. The physicochemical and estimated glycemic index (eGI) of the Black and Pinto bean starches treated with ozone were not significantly (P>0.05) different than that of their respective control starches. Annealed starches had improved thermal and pasting properties compared to native starches. Acetylated starches presented reduced syneresis, good pasting properties and lower eGI. Also, all modified starches had increased levels of resistant starch (RS). Therefore, the digestibility and physicochemical properties of bean starch were affected by the type of modification but there were no significant (P>0.05) differences between the Black and Pinto bean starches. PMID:23442623

Simsek, Senay; Ovando-Martínez, Maribel; Whitney, Kristin; Bello-Pérez, Luis A



The Potato Tuber Mitochondrial Proteome1[W][OPEN  

PubMed Central

Mitochondria are called the powerhouses of the cell. To better understand the role of mitochondria in maintaining and regulating metabolism in storage tissues, highly purified mitochondria were isolated from dormant potato tubers (Solanum tuberosum ‘Folva’) and their proteome investigated. Proteins were resolved by one-dimensional gel electrophoresis, and tryptic peptides were extracted from gel slices and analyzed by liquid chromatography-tandem mass spectrometry using an Orbitrap XL. Using four different search programs, a total of 1,060 nonredundant proteins were identified in a quantitative manner using normalized spectral counts including as many as 5-fold more “extreme” proteins (low mass, high isoelectric point, hydrophobic) than previous mitochondrial proteome studies. We estimate that this compendium of proteins represents a high coverage of the potato tuber mitochondrial proteome (possibly as high as 85%). The dynamic range of protein expression spanned 1,800-fold and included nearly all components of the electron transport chain, tricarboxylic acid cycle, and protein import apparatus. Additionally, we identified 71 pentatricopeptide repeat proteins, 29 membrane carriers/transporters, a number of new proteins involved in coenzyme biosynthesis and iron metabolism, the pyruvate dehydrogenase kinase, and a type 2C protein phosphatase that may catalyze the dephosphorylation of the pyruvate dehydrogenase complex. Systematic analysis of prominent posttranslational modifications revealed that more than 50% of the identified proteins harbor at least one modification. The most prominently observed class of posttranslational modifications was oxidative modifications. This study reveals approximately 500 new or previously unconfirmed plant mitochondrial proteins and outlines a facile strategy for unbiased, near-comprehensive identification of mitochondrial proteins and their modified forms. PMID:24351685

Salvato, Fernanda; Havelund, Jesper F.; Chen, Mingjie; Rao, R. Shyama Prasad; Rogowska-Wrzesinska, Adelina; Jensen, Ole N.; Gang, David R.; Thelen, Jay J.; Møller, Ian Max



Altered inhibition in Tuberous Sclerosis and Type IIb cortical dysplasia  

PubMed Central

Objective The most common neurological symptom of tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD) is early-life refractory epilepsy. As previous studies have shown enhanced excitatory glutamatergic neurotransmission in TSC and FCD brains, we hypothesized that neurons associated with these lesions may also express altered GABAA receptor (GABAAR)-mediated inhibition. Methods Expression of the GABAAR subunits?1 and ?4, the Na+-K+-2Cl? (NKCC1), and the K+?Cl? (KCC2) transporters in human TSC and FCD Type II specimens were analyzed by Western blot and double label immunocytochemistry. GABAAR responses in dysplastic neurons from a single case of TSC were measured by perforated-patch recording and compared to normal-appearing cortical neurons from a non-TSC epilepsy case. Results TSC and FCD Type IIb lesions demonstrated decreased expression of the GABAAR ?1, increased NKCC1 and decreased KCC2 levels. In contrast, FCD Type IIa lesions showed decreased ?4, and increased expression of both NKCC1 and KCC2 transporters. Patch clamp recordings from dysplastic neurons in acute slices from TSC tubers demonstrated excitatory GABAAR responses that were significantly attenuated by the NKCC1 inhibitor bumetanide, in contrast to hyperpolarizing GABAAR-mediated currents in normal neurons from non-TSC cortical slices. Interpretation Expression and function of GABAARs in TSC and FCD IIb suggests the relative benzodiazepine insensitivity and more excitatory action of GABA compared to FCD IIa. These factors may contribute to resistance of seizure activity to anticonvulsants that increase GABAergic function, and may justify add-on trials of the NKCC1 inhibitor bumetanide for the treatment of TSC and FCD Type IIb related epilepsy. PMID:22447678

Talos, Delia M.; Sun, Hongyu; Kosaras, Bela; Joseph, Annelise; Folkerth, Rebecca D.; Poduri, Annapurna; Madsen, Joseph R.; Black, Peter M.; Jensen, Frances E.



Components interactions controlling starch-kaolinite composite films properties.  


In order to relate the primary filler-matrix interactions to the macroscopic properties of starch-kaolinite composite material, these interactions are monitored through homo- or hetero-coagulation experiments involving both components. Turbidity measurement and Infrared spectra confirm the extreme weakness of the interactions. The addition of calcium cations shows that these weak interactions between starch and kaolinite are due to the combination of the electrostatic repulsion and hydrogen bonds formation between this two negatively charge components. Some possible relationships between the starch-kaolinite interactions and starch-kaolinite composite films properties are proposed. PMID:25498695

Mbey, J A; Thomas, F



The Or gene enhances carotenoid accumulation and stability during post-harvest storage of potato tubers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Provitamin A carotenoids in staple crops are not very stable during storage and their loss compromises nutritional quality. To elucidate the fundamental mechanisms underlying carotenoid accumulation and stability, we investigated transgenic potato tubers that express the cauliflower Orange (Or) gene...


The Laccaria and Tuber Genomes Reveal Unique Signatures of Mycorrhizal Symbiosis Evolution (2010 JGI User Meeting)  

SciTech Connect

Francis Martin from the French agricultural research institute INRA talks on how "The Laccaria and Tuber genomes reveal unique signatures of mycorrhizal symbiosis evolution" on March 24, 2010 at the 5th Annual DOE JGI User Meeting

Knapp, Steve



Quick genetic screening using targeted next-generation sequencing in patients with tuberous sclerosis.  


Tuberous sclerosis complex is an autosomal dominant disorder characterized by hamartomas in multiple organ systems. Mutations in the 2 large genes TSC1 and TSC2 have been demonstrated to be associated with tuberous sclerosis complex by various mutation screening methods. Targeted next-generation sequencing for genetic analysis is performed in the current study and is proved to be less cost, labor, and time consuming compared with Sanger sequencing. Two de novo and 1 recurrent TSC2 mutation in patients with tuberous sclerosis complex were revealed. Clinical details of patients were described and the underlying mechanism of the 2 novel TSC2 mutations, c.245G>A(p.W82X) and c.5405_5408dupACTT(p.P1803Lfs*25), were discussed. These results added to variability of TSC mutation spectrum and suggest that targeted next-generation sequencing could be the primary choice over Sanger sequencing in future tuberous sclerosis complex genetic counseling. PMID:24789117

Liu, Qing; Huang, Yan; Zhang, Mingrong; Wang, Lian Qing; Guo, Xia Nan; Si, Nuo; Qi, Zhan; Zhou, Xiang Qin; Cui, Li-Ying



Infection of potato tubers by common scab (Streptomyces scabies) during brief periods when soil is drying  

Microsoft Academic Search

Plots of chitted and unchittedMajestic seed planted in soil naturally infested withStreptomyces scabies, were trickle irrigated to prevent infection except during 5, 10 or 15 days from when plants from unchitted seed began to form tubers.

D. H. Lapwood; T. F. Hering



Amylose and Amylopectin Interact in Retrogradation of Dispersed High-Amylose Starches  

Microsoft Academic Search

Cereal Chem. 76(2):282-291 Retrogradation of three high-amylose starches (HAS: ae du, ae V, and ae VII) and common corn starch (CCS) was examined by dynamic oscil- latory rheometry (7.5% (w\\/w) starch in 20% (v\\/v) dimethyl sulfoxide (DMSO)), differential scanning calorimetry (DSC; 30% (w\\/w) starch in water), and turbidity (0.5% (w\\/w) starch in 20% (v\\/v) DMSO). Nongran- ular lipid-free starch and

Jeffrey D. Klucinec; Donald B. Thompson



Enzymatic production of linear long-chain dextrin from sago ( Metroxylon sagu) starch  

Microsoft Academic Search

Pullulanase (EC. was used to generate more linear-chain dextrin from sago starch (24.9% amylose) such that the resulting product could act as a high amylose starch. A starch suspension of 5.0% (w\\/v) sago starch was heated at 100°C for 45min and, after cooling, the gelatinized sago starch was hydrolyzed with 2.0% (v\\/dry weight starch) pullulanase (Promozyme 400L, Novozymes A\\/S, Denmark)

C. W. Wong; S. K. S. Muhammad; M. H. Dzulkifly; N. Saari; H. M. Ghazali



Novel polymer blends with thermoplastic starch  

NASA Astrophysics Data System (ADS)

A new class of polymers known as "bioplastics" has emerged and is expanding rapidly. This class consists of polymers that are either bio-based or biodegradable, or both. Among these, polysaccharides, namely starch, are of great interest for several reasons. By gelatinizing starch via plasticizers, it can be processed in the same way as thermoplastic polymers with conventional processing equipment. Hence, these bio-based and biodegradable plastics, with their low source and refinery costs, as well as relatively easy processability, have made them ideal candidates for incorporation into various current plastic products. Four different plasticizers have been chosen here for gelatinization of thermoplastic starch (TPS): glycerol, sorbitol, diglycerol and polyglycerol, with the latter two being used for the first time in such a process. Two methodological categories are used. The first involves a calorimetric method (Differential Scanning Calorimetry) as well as optical microscopy; these are "static" methods where no shear is applied A wide range of starch/water/plasticizer compositions were prepared to explore the gelatinization regime for each plasticizer. The onset and conclusion gelatinization temperatures for sorbitol and glycerol were found to be in the same vicinity, while diglycerol and polyglycerol showed significantly higher transition temperatures. The higher molecular weight and viscosity of polyglycerol allow this transition to occur at an even higher temperature than with diglycerol. This is due to the increase in molecular weight and viscosity of the two new plasticizers, as well as their significant decrease in water solubility. It is demonstrated that the water/plasticizer ratio has a pronounced effect on gelatinization temperatures. When plasticizer content was held constant and water content was increased, it was found that the gelatinization temperature decreased for all the plasticizers. Meanwhile, when the water content was held constant and the plasticizer content was increased, the gelatinization temperature increased for glycerol, sorbitol and diglycerol, but it moved in the opposite direction in the case of polyglycerol. The gelatinization temperature variation for glycerol, sorbitol and diglycerol caused by changing water and plasticizer content indicates that water is the primary agent causing granular swell and plasticization in the gelatinization process. Due to the high molecular weight and viscosity, as well as the low hydroxyl group density (~ one --OH per two carbon) and borderline solubility of polyglycerol in water, it is believed that water-aided penetration of the plasticizer among the crystalline structure of starch molecules is significantly decelerated. So it is proposed that in the case of low-water solubility of the plasticizers, gelatinization temperature is determined more by the total amount of the plasticizer and water, rather than the water/plasticizer ratio. Increasing the miscibility of polyglycerol in water by increasing the temperature of the initial slurry, results in a return of the system to the typical thermal dependence of gelatinization with plasticizer/water ratio. Secondly, the gelatinization of starch under "dynamic conditions" was studied. In this case, a constant shear is applied to the slurry, along with a temperature ramp to induce gelatinization. This is, in fact, a rheological technique that heats up the slurry, while a mechanical shear is applied throughout. The reason for using this method is that in the plastic industry, thermoplastic starch is produced via processes involving shear such as extrusion, but, to date, there has not yet been a thorough study on the effect of pure shear on the gelatinization process. Glycerol, diglycerol and sorbitol were subjected to different dynamic gelatinization treatments in a couette flow system, and the results were compared with static gelatinization. Applying shear showed virtually no effect on the onset gelatinization temperature. However, the conclusion temperature was remarkably reduced

Taghizadeh, Ata


The effect of rice variety and starch isolation method on the pasting and rheological properties of rice starch pastes  

Microsoft Academic Search

The effect of rice variety and starch isolation method on the pasting and rheological properties of rice starches was evaluated. One waxy and three non-waxy rice varieties from California with a range of amylose contents of 1.6–26.5% and four methods of isolation were evaluated. A rotational rheometer (RR) was used to measure the pasting and rheological properties of starch dispersions

Fang Zhong; Yue Li; Ana María Ibáñez; Moon Hun Oh; Kent S. McKenzie; Charles Shoemaker



Oral immunisation of naive and primed animals with transgenic potato tubers expressing LT-B  

Microsoft Academic Search

The efficacy of edible vaccines produced in potato tubers was examined in mice. Transgenic plants were developed by Agrobacterium tumefaciens-mediated transformation. The antigen selected was the non-toxic B subunit of the Escherichia coli enterotoxin (recLT-B). A synthetic gene coding for recLT-B was made and optimised for expression in potato tubers and accumulation in the endoplasmic reticulum. Introduction of this gene

T. G. M. Lauterslager; D. E. A. Florack; T. J. van der Wal; J. W. Molthoff; J. P. M. Langeveld; D. Bosch; L. A. Th. Hilgers



Catalase inhibition accelerates dormancy release and sprouting in potato (Solanum tuberosum L.) tubers  

Microsoft Academic Search

The involvement of hydrogen peroxide (H2O2) metabolism in dormancy release and sprouting of potato (Solanum tuberosum L.) tubers has been investigated using three complementary approaches. In the fi rst approach, the evolution of the sprouting kinetics, H2O2 content and antioxidant enzyme activities were examined during tuber storage. The most important changes occurred at the « bud\\/sprout » level. In particular,

Mohammed Bajji; Frédéric Gastiny



Tuberous sclerosis and polycystic kidney disease in a 3-month-old infant  

Microsoft Academic Search

Tuberous sclerosis (TSC) is an autosomal dominantly inherited multisystemic disease characterized by the development of hamartomas predominantly in brain and kidneys. The TSC2 gene for tuberous sclerosis is localized on chromosome 16p13.3 immediately adjacent to PKD1, the gene for autosomal dominant polycystic kidney disease (ADPKD). A TSC2-PKD1 contiguous gene syndrome caused by chromosomal microdeletions disrupting both the TSC2 and PKD1

Martin W. Laass; Miriam Spiegel; Anna Jauch; Gabriele Hahn; Edgar Rupprecht; Christian Vogelberg; Oliver Bartsch; Angela Huebner



The effects of (S)-(+)-carvone treatments on seed potato tuber dormancy and sprouting  

Microsoft Academic Search

Summary  Potato seed tubers may suffer from premature sprouting during storage, thus limiting their suitability for cultivation. Commonly\\u000a used sprout suppressant treatments negatively affect but viability and therefore a reliable method to inhibit bud development\\u000a must still be found for seed tubers. The monoterpene carvone ((S)-(+)-carvone) was tested in small scale experiments. The\\u000a vapour of this compound fully inhibited bud growth

Carlo Sorce; Roberto Lorenzi; Paolo Ranalli



Correlation of phytotoxin production with pathogenicity of Streptomyces scabies isolates from scab infected potato tubers  

Microsoft Academic Search

A total of 23 isolates obtained from scab infected potato tubers representative of six sampling areas in Eastern and Central\\u000a Canada and five ATCCStreptomyces strains were screened for pathogenicity on the basis of their ability to initiate scab development on aseptically cultured\\u000a minitubers and plant generated tubers. The results were then correlated with any associated generation of the scab inducing

Russell R. King; C. Harold Lawrence; Mervyn C. Clark



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

PubMed Central

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

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



Multigene engineering of starch biosynthesis in maize endosperm increases the total starch content and the proportion of amylose.  


Maize (Zea mays spp. mays) is a staple crop for more than 900 million people. The seeds or kernels provide a rich source of calories because ~70% of the weight is carbohydrate, mostly in the form of starch. The content and composition of starch are complex traits controlled by many genes, offering multiple potential targets for intervention. We used a multigene engineering approach combining the overexpression of Bt2, Sh2, Sh1 and GbssIIa (to enhance the activity of sucrose synthase, AGPase and granule-bound starch synthase) with the suppression of SbeI and SbeIIb by RNA interference (to reduce the activity of starch branching enzyme). Maize plants expressing all six genes plus the selectable marker showed a 2.8-7.7% increase in the endosperm starch content and a 37.8-43.7% increase in the proportion of amylose, which was significant compared to untransformed control plants. We also observed improvements in other agronomic traits, such as a 20.1-34.7% increase in 100-grain weight, a 13.9-19.0% increase in ear weight, and larger kernels with a better appearance, presumably reflecting the modified starch structure within the kernels. Our results confirm that multigene engineering applied to the starch biosynthesis pathway can not only modulate the quality and quantity of starch but can also improve starch-dependent agronomic traits. PMID:23740205

Jiang, Lili; Yu, Xiaoming; Qi, Xin; Yu, Qian; Deng, Sen; Bai, Bing; Li, Ning; Zhang, Ai; Zhu, Changfu; Liu, Bao; Pang, Jinsong



Yellow nutsedge (Cyperus esculentus L. ) control with herbicides: the role of tuberization  

SciTech Connect

Trials were carried out under greenhouse, growth chamber, laboratory, outdoor pot, and field conditions to characterize stages of yellow nutsedge tuberization and to investigate the influence of herbicides. The effects of herbicides on tuberization and phytotoxicity at several growth stages, as well as on sprouting, growth characteristics, and survival of new tubers were determined. Tuberization was a continuous process, but was modulated by plant age and environmental conditions. The growth stage that included the time of first tuber initiation was the best for applying glyphosate (N-(phosphonomethyl)glycine) and oxyfluorfen (2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluromethyl)benzene). Plant-age and length of period after spraying influenced glyphosate and oxyfluorfen absorption and translocation. Addition of unlabelled oxyfluorfen as a tank mixture can glyphosate increased absorption of /sup 14/C-glyphosate to 27% after 1 day and 46% after 8 days and increased translocation into other plant parts. Timing of postemergence herbicide applications relative to tuberization is crucial for overall control of yellow nutsedge. When soil applied herbicides were compared in the field, consecutive applications of dichlobenil (2,6-dichlorobenzonitrile) and metolachlor (2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide) for two years provided the best control of nutsedge.

Pereira, W.



Hypoxic Stress Inhibits Multiple Aspects of the Potato Tuber Wound Response  

PubMed Central

Potato (Solanum tuberosum L.) tubers subjected to wounding under hypoxic stress do not synthesize RNA species that are induced in response to wounding in aerobic conditions. Further, wound-response proteins fail to be synthesized when wounded tubers are transferred to hypoxic conditions although messenger RNAs which encode them persist for many hours after transfer. Hypoxic stress also prevents the incorporation of [3H]thymidine by wounded tubers that occurs in aerobic conditions. In contrast, hypoxic tubers accumulate and translate transcripts of genes whose products are involved in anaerobic metabolism whether or not they are wounded. Both the hypoxic response and the aerobic wound response preclude the synthesis of proteins encoded by messenger RNAs which accumulated during the tuberization process and which can be translated in vitro. Finally, wounding elicits the degradation of a subset of these tuberization-associated transcripts. These data indicate a complex and precise regulation of gene expression at several levels of macromolecular synthesis. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:16667446

Butler, William; Cook, Linda; Vayda, Michael E.



Color It!  

NSDL National Science Digital Library

It doesn't take a Photoshop expert to create attractive graphics for the Web. To prove this, the folks at MicroFrontier have released three graphic creation/editing packages for the Macintosh, each aimed at a different user level. All three applications support Photoshop 3.0 compatible plug-ins and basic features such as scanner support, image and resolution scaling, and basic image enhancement. Color It! adds the ability to create animated GIFs, PNG, and progressive JPEG files, and client- and server-side image maps. It also supports an enhanced set of filters, fills, and imaging tools. A save-disabled demo version of each application is available at the MicroFrontier Website. The price for Color It! is $49.95.


Overexpression of a bacterial 1-deoxy-D-xylulose 5-phosphate synthase gene in potato tubers perturbs the isoprenoid metabolic network: implications for the control of the tuber life cycle  

Microsoft Academic Search

Potato tubers were engineered to express a bacterial gene encoding 1-deoxy-D-xylulose 5-phosphate synthase (DXS) in order to investigate the effects of perturbation of isoprenoid biosynthesis. Twenty-four independent transgenic lines out of 38 generated produced tubers with significantly elongated shape that also exhibited an early tuber sprouting phenotype. Expression analy- sis of nine transgenic lines (four exhibiting the pheno- type and

Wayne L. Morris; Laurence J. M. Ducreux; Peter Hedden; Steve Millam; Mark A. Taylor



Physicochemical properties of starch in Chlorella change depending on the CO 2 concentration during growth: Comparison of structure and properties of pyrenoid and stroma starch  

Microsoft Academic Search

Structure and properties of pyrenoid and stroma starch were compared in Chlorella. To obtain pyrenoid starch- and stroma starch-enriched samples of high purity, we investigated the effects of the CO2 concentration and growth phase on the intracellular amount and localization of starch. In cells grown with air containing 3% CO2 (high-CO2 cells) at the log phase, starch was accumulated primarily

Asako Izumo; Shoko Fujiwara; Yasunori Oyama; Aya Satoh; Naoko Fujita; Yasunori Nakamura; Mikio Tsuzuki



The deposition and characterization of starch in Brachypodium distachyon  

PubMed Central

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

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



The deposition and characterization of starch in Brachypodium distachyon.  


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

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



New Starch Phenotypes Produced by TILLING in Barley  

PubMed Central

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

Sparla, Francesca; Falini, Giuseppe; Botticella, Ermelinda; Pirone, Claudia; Talamè, Valentina; Bovina, Riccardo; Salvi, Silvio; Tuberosa, Roberto; Sestili, Francesco; Trost, Paolo



Oxidative Stress Results in lncreased Sinks for Metabolic Energy during Aging and Sprouting of Potato Seed-Tubers  

Microsoft Academic Search

Glutathione-mediated free-radical-scavenging and plasma mem- brane ATPase activities increase as sinks for metabolic energy with advancing tuber age. Plasma membrane ATPase activity from 19- month-old tubers was 77% higher than that from 7-month-old tubers throughout sprouting. The higher activity was not attended by an increase in the amount of ATPase per unit plasma membrane protein. Concentrations of oxidized (CSSC) and

C. N. Mohan Kumar; N. Richard Knowles


The surface-associated proteins of wheat starch granules: suitability of wheat starch for celiac patients  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wheat starch is used to make baked products for celiac patients in several European countries, but is avoided in the US because of uncertainty about the amounts of associated grain storage (gluten) proteins. People with celiac disease (CD) must avoid wheat, rye and barley proteins and products that...


The Characterization of Modified Starch Branching Enzymes: Toward the Control of Starch Chain-Length Distributions  

PubMed Central

Starch is a complex branched glucose polymer whose branch molecular weight distribution (the chain-length distribution, CLD) influences nutritionally important properties such as digestion rate. Chain-stopping in starch biosynthesis is by starch branching enzyme (SBE). Site-directed mutagenesis was used to modify SBEIIa from Zea mays (mSBEIIa) to produce mutants, each differing in a single conserved amino-acid residue. Products at different times from in vitro branching were debranched and the time evolution of the CLD measured by size-exclusion chromatography. The results confirm that Tyr352, Glu513, and Ser349 are important for mSBEIIa activity while Arg456 is important for determining the position at which the linear glucan is cut. The mutant mSBEIIa enzymes have different activities and suggest the length of the transferred chain can be varied by mutation. The work shows analysis of the molecular weight distribution can yield information regarding the enzyme branching sites useful for development of plants yielding starch with improved functionality. PMID:25874689

Li, Cheng; Wu, Alex Chi; Go, Rob Marc; Malouf, Jacob; Turner, Mark S.; Malde, Alpeshkumar K.; Mark, Alan E.; Gilbert, Robert G.



Flocculation of Kaolin by Waxy Maize Starch Phosphates  

Technology Transfer Automated Retrieval System (TEKTRAN)

Waxy maize starch phosphates were tested as flocculants in order to determine if they have the potential to replace petroleum-based polymer flocculants currently used commercially. Phosphorylation was carried out by drying heating of starches and sodium orthophosphates at 140 deg C for 4 h. Native...


Thermal dissolution of maize starches in aqueous medium  

Technology Transfer Automated Retrieval System (TEKTRAN)

Starches are not soluble in neutral water at room temperature. However, if they are heated in a closed container beyond the boiling point of water, they eventually dissolve. The dissolution temperature depends on the type of starch. The dissolution process was monitored in real time by measuring ...



Technology Transfer Automated Retrieval System (TEKTRAN)

Starch-lipid composites (SLCs) have been used as fat replacers and stabilizers in beef patties, dairy products, and baked goods and the technology has been patented under the trademark FanteskTM. The SLCs are produced by mixing aqueous starch slurry with a lipid source, and steam jet-cooking. The ...


Root starches other than those of white and sweet potato  

Microsoft Academic Search

Such starches are not produced in the United States but are imported. Tapioca, from cassava roots, constitutes about 86% of\\u000a them and is particularly valued in the food and adhesive industries. Sago from the pith of palm trees and cycads is used primarily\\u000a as an adhesive; arrowroot from a rhizome as a food starch.

O. B. Wurzburg



Individual mammalian mucosal glucosidase subunits digest various starch structures differently  

Technology Transfer Automated Retrieval System (TEKTRAN)

Starch digestion in the human body requires two luminal enzymes,salivary and pancreatic alpha-amylase (AMY), and four small intestinal mucosal enzyme activities related to the maltase-glucoamylase (MGAM) and sucrase-isomaltase (SI) complexes. Starch consists of two polysaccharides, amylose (AM) and ...


Humidity-responsive starch-poly (methyl acrylate) films.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Blown films prepared from starch-poly(methyl acrylate) graft copolymers plasticized with urea and water display shrinkage at relative humidities greater than 50%. Shrinkage at relative humidities below approximately 75% is strongly correlated with the urea/starch weight ratio, which controls the eq...


Physicochemical properties of cassava starch oxidized by sodium hypochlorite.  


In this work, cassava starch was modified by treatment with sodium hypochlorite (NaClO) at different concentrations (0.8, 2.0 and 5.0 % of active chlorine) and selected physicochemical properties of the oxidized starches were investigated. The native and modified samples were evaluated considering moisture, carboxyl content, apparent viscosity, susceptibility to syneresis, mid-infrared spectroscopy and crystallinity index. The treatment with NaClO resulted in alterations in carboxyl content of the oxidized starches that increased with increasing concentration of the oxidant. Oxidized starches also showed higher susceptibility to syneresis, as assessed by the release of liquid during freezing and thawing. Apparent viscosity analysis showed decrease in peak viscosity of the oxidized starches. X-ray diffractograms showed that the oxidation influenced the extent of cassava starch relative crystallinity found to lie between 34.4 % (native) and 39.9 % (2.0 % active chlorine). The infrared spectra are sensitive to structural changes on starch macromolecules and presented characteristic peaks as C-O-C of the six carbon glucose ring absorbs at 1,150-1,085 cm(-1) and due to axial deformation these bands changed with the crystal structure of the starch samples. PMID:25328206

Garrido, Lúcia Helena; Schnitzler, Egon; Zortéa, Manoela Estefânea Boff; de Souza Rocha, Thaís; Demiate, Ivo Mottin



Analysis of Cereal Starches by High Performance Size Exclusion Chromatography  

Technology Transfer Automated Retrieval System (TEKTRAN)

Starch has unique physicochemical characteristics among carbohydrates. Most starch granules are a mixture of two sugar polymers: a highly branched polysaccharide named amylopectin, and a basically linear polysaccharide named amylose. The objective of this study was to develop a simple, one-step and ...


Influence of amylose content on starch films and foams  

Microsoft Academic Search

After extraction of smooth pea starch and waxy maize starch from pure amylose and amylopectin fractions, films with various amylose contents were prepared by casting in the presence of water or water with glycerol. For unplasticized films, a continuous increase in tensile strength (40–70 MPa) and elongation (4–6%) was observed as amylose increased from 0 to 100%. Discrepancies with values

Denis Lourdin; Guy Della Valle; Paul Colonna




Technology Transfer Automated Retrieval System (TEKTRAN)

Laser diffraction sizing (LDS) was used to measure particle size distributions of wheat flour and isolated starch to determine if the method could be used as a component for predicting end-use quality. Five hard red winter and five soft red winter wheats were milled into flour from which starch was...


The pasting properties of sonicated waxy rice starch suspensions.  


The effect of sonication on the pasting properties of waxy rice starch solutions (5 wt%) was investigated. It has been found that the functionality of starch granules was significantly influenced by the length of sonication and the solution temperature. A comparison of the pasting behaviour showed that the peak and final viscosities of the starch dispersions sonicated at temperatures near the onset temperature of gelatinisation were lower than those of the non-sonicated dispersions. The particle size measurements showed that the size of the heated and sonicated granules were smaller than that of the heated non-sonicated starch granules. Scanning electron microscopy (SEM) observations showed that the starch granule surface was not affected by sonication, and the size exclusion chromatography did not show any reduction in the size of the starch molecules. Based on these observations, the change in the pasting behaviour is explained in terms of the solubilisation of the swollen starch granules and starch aggregates induced by sonication. PMID:19201242

Zuo, Jenny Yue; Knoerzer, Kai; Mawson, Raymond; Kentish, Sandra; Ashokkumar, Muthupandian



Biosysthesis of Corn Starch Palmitate by Lipase Novozym 435  

PubMed Central

Esterification of starch was carried out to expand the usefulness of starch for a myriad of industrial applications. Lipase B from Candida antarctica, immobilized on macroporous acrylic resin (Novozym 435), was used for starch esterification in two reaction systems: micro-solvent system and solvent-free system. The esterification of corn starch with palmitic acid in the solvent-free system and micro-solvent system gave a degree of substitution (DS) of 1.04 and 0.0072 respectively. Esterification of corn starch with palmitic acid was confirmed by UV spectroscopy and IR spectroscopy. The results of emulsifying property analysis showed that the starch palmitate with higher DS contributes to the higher emulsifying property (67.6%) and emulsion stability (79.6%) than the native starch (5.3% and 3.9%). Modified starch obtained by esterification that possesses emulsifying properties and has long chain fatty acids, like palmitic acid, has been widely used in the food, pharmaceutical and biomedical applications industries. PMID:22837690

Xin, Jia-Ying; Wang, Yan; Liu, Tie; Lin, Kai; Chang, Le; Xia, Chun-Gu



Biosysthesis of corn starch palmitate by lipase novozym 435.  


Esterification of starch was carried out to expand the usefulness of starch for a myriad of industrial applications. Lipase B from Candida antarctica, immobilized on macroporous acrylic resin (Novozym 435), was used for starch esterification in two reaction systems: micro-solvent system and solvent-free system. The esterification of corn starch with palmitic acid in the solvent-free system and micro-solvent system gave a degree of substitution (DS) of 1.04 and 0.0072 respectively. Esterification of corn starch with palmitic acid was confirmed by UV spectroscopy and IR spectroscopy. The results of emulsifying property analysis showed that the starch palmitate with higher DS contributes to the higher emulsifying property (67.6%) and emulsion stability (79.6%) than the native starch (5.3% and 3.9%). Modified starch obtained by esterification that possesses emulsifying properties and has long chain fatty acids, like palmitic acid, has been widely used in the food, pharmaceutical and biomedical applications industries. PMID:22837690

Xin, Jia-Ying; Wang, Yan; Liu, Tie; Lin, Kai; Chang, Le; Xia, Chun-Gu



Alternative utilization of wheat starch, Grafton, North Dakota  

SciTech Connect

In 1978, North Dakota State University (NDSU), in cooperation with the Economic Development Administration, completed a study of the feasibility of a vital wheat gluten starch processing plant in North Dakota. The overall objective of this study is to determine the most feasible alternatives for utilizing the by-product starch slurry from a vital wheat gluten processing plant.

Not Available



Waste management in the Tapioca based starch industry  

Microsoft Academic Search

The tapioca based starch industry is addressed. Presented are the process details, water consumption and wastewater generation and characteristics, solid waste generation and low and non?waste technologies of production. Bench scale treatability studies were conducted to reach the most viable treatment option for treatment of starch wastewater. A total of five treatment options with recourse to energy recovery were suggested.

T. Nandy; S. N. Kaul; V. S. S. Sekhar



68 CEREAL CHEMISTRY Variability in Starch Acetylation Efficiency  

E-print Network

68 CEREAL CHEMISTRY Variability in Starch Acetylation Efficiency from Commercial Waxy Corn Hybrids. Six waxy corn (maize) hybrids from 1998 and five waxy corn hybrids from 1999 were wet, and reduced retro- gradation upon cooling (Rutenberg and Solarek 1984). Corn (maize) starch obtained by wet


Potential Targets for Seed Improvement through Bioengineering Starch Synthesis Pathways  

Technology Transfer Automated Retrieval System (TEKTRAN)

Starch is the principle carbohydrate in the food chain and is a renewable and biodegradable polymer widely used in the food, beverage, paper, textile, and livestock feed industries. It is the major component of the harvestable organs in many agronomic plants. The quantity and quality of starch thus ...



Technology Transfer Automated Retrieval System (TEKTRAN)

The relationships that starch has with profitable production or with health disorders in cattle advise closer accounting of its quantity and quality in diets. Native starch is an -(1-4)-linked-glucan with -(1-6) linked branch points found in crystalline granules in plants. In feedstuffs, it can b...


In vitro starch digestion in sorghum flour from Algerian cultivars  

PubMed Central

This work aims to evaluate starch digestion in whole sorghum grains. Nine sorghum cultivars were sampled from the Sahara of Algeria. The structural characteristics of sorghum grains were measured. Total starch (TS) varied between 67.67% and 74.82%, digestible starch (DS) between 64.34% and 69.70%, and resistant starch (RS) ranged from 2.55% to 7.98%. The kinetic of starch digestion displayed first-order model. For all sorghum cultivars, starch were digested with different extents, DS at infinite time (D?) ranged from 52.58 to 102.13 g/100 g dry starch, while the hydrolysis index (HI) ranged from 41.55% to 76.93% and high average glycemic index (GIavg) ranged from 65.97 to 94.14. The results showed that there are differences in grain quality of Algerian sorghum cultivars. The starch fractions have acceptable nutritional value with good in vitro digestibility characteristics suitable for human health and nutrition. PMID:24936295

Souilah, Rachid; Djabali, Djaffar; Belhadi, Badreddine; Mokrane, Hind; Boudries, Nadia; Nadjemi, Boubekeur




Technology Transfer Automated Retrieval System (TEKTRAN)

The flow and structural properties of pastes prepared from high amylose corn starch were examined. The starch was cooked in an excess-steam jet cooker in the presence of a fatty acid. The cooked product was rapidly cooled and then freeze dried or drum dried. Amylose is removed from solution by for...



Technology Transfer Automated Retrieval System (TEKTRAN)

Starch-kraft lignin-glycerol blends were extruded in a twin-screw extruder to produce non-brittle films. One week after extrusion, films with a mid-range composition of 52% starch, 20% lignin, and 28% glycerol showed a tensile strength at break of 2.8 MPa, Young's modulus of 48 MPa, and elongation ...


Autophagy Contributes to Leaf Starch Degradation[C][W  

PubMed Central

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

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



Flavonoid profiling and transcriptome analysis reveals new gene–metabolite correlations in tubers of Solanum tuberosum L.  

PubMed Central

Anthocyanin content of potato tubers is a trait that is attracting increasing attention as the potential nutritional benefits of this class of compound become apparent. However, our understanding of potato tuber anthocyanin accumulation is not complete. The aim of this study was to use a potato microarray to investigate gene expression patterns associated with the accumulation of purple tuber anthocyanins. The advanced potato selections, CO97216-3P/PW and CO97227-2P/PW, developed by conventional breeding procedures, produced tubers with incomplete expression of tuber flesh pigmentation. This feature permits sampling pigmented and non-pigmented tissues from the same tubers, in essence, isolating the factors responsible for pigmentation from confounding genetic, environmental, and developmental effects. An examination of the transcriptome, coupled with metabolite data from purple pigmented sectors and from non-pigmented sectors of the same tuber, was undertaken to identify these genes whose expression correlated with elevated or altered polyphenol composition. Combined with a similar study using eight other conventional cultivars and advanced selections with different pigmentation, it was possible to produce a refined list of only 27 genes that were consistently differentially expressed in purple tuber tissues compared with white. Within this list are several new candidate genes that are likely to impact on tuber anthocyanin accumulation, including a gene encoding a novel single domain MYB transcription factor. PMID:20110266

Stushnoff, Cecil; Ducreux, Laurence J. M.; Hancock, Robert D.; Hedley, Pete E.; Holm, David G.; McDougall, Gordon J.; McNicol, James W.; Morris, Jenny; Morris, Wayne L.; Sungurtas, Julie A.; Verrall, Susan R.; Zuber, Tatiana; Taylor, Mark A.



Development of a Starch Iodide Method for the Determination of Phosphite in Natural Waters.  

NASA Astrophysics Data System (ADS)

Phosphorus (P) is believed to occur almost exclusively in the environment as fully oxidized phosphate (H3PO4, oxidation state +V). Recent developments in the field of microbiology and research on the origin of life have suggested a possibly significant role for reduced, inorganic forms of P such as phosphorus acid [H3PO3, P(+III)], hypophosphorus acid [H3PO2, P(+I)] and various forms of phosphides [P(-III)] in the biogeochemical cycling of P. In order to confirm the importance of reduced forms of P, we need to develop new and better methods for the detection of these compounds in the environment, often at levels below 1 mM. Traditional methods of P determination are based on the reaction of P with acidified molybdate in aqueous solution to yield phosphomolybdate heteropolyacid, which is then reduced and analyzed spectrophotometrically to quantify the total amount of P in the sample. Limitations in this technique have resulted in our development of a new method using a starch iodide complex for the detection of phosphorus acid or phosphite. Under laboratory conditions, phosphite [P (+III)] is oxidized to phosphate [P (+V)] by tri-iodide (I3). Starch reacts with excess tri-iodide present in solution to form a blue colored complex having a ? max of 580 nm. The I3, as well as other species such as I5, are responsible for the formation of the complex when they fit inside the coiled amylose structure of starch. Linear determination is possible in water samples containing 1 - 80 mM of P (+III). Measurement of the loss of blue color complex can then be correlated with phosphite concentration in the starting sample. Current efforts to optimize this method in order to reach limits of detection below 1 mM are underway. We believe that with better detection methods, the evidence for reduced P in the environment will increase. Due to chemical kinetics, microbial activity, surface catalyzed reactions and possible storage effects, it is difficult to effectively measure the low concentrations present after removing the samples from their natural environments for laboratory analysis. Therefore, to fully understand the importance of reduced P, ultimately, we hope to develop the starch iodide method into an in situ detection technique for measuring phosphite directly in natural waters where sensitive and reliable field-based methods of analysis are needed.

Barco, R. A.; Patil, D.; Salmassi, T. M.; Hanrahan, G.



Enzymatic esterification of starch using recovered coconut oil.  


Modification of maize and cassava starches was done using recovered coconut oil and microbial lipase. Microwave esterification was advantageous as it gave a DS 1.55 and 1.1 for maize starch and cassava starch, respectively. Solution state esterification of cassava starch for 36 h at 60 degrees C gave a DS of 0.08 and semi-solid state esterification gave a DS of 0.43. TGA and DSC studies showed that the higher DS attributed to the thermostability, since onset of decomposition is at a higher temperature (492 degrees C) than the unmodified (330 degrees C) and was stable above 600 degrees C. alpha-Amylase digestibility and viscosity reduced for modified starch. PMID:16730792

Rajan, Akhila; Prasad, V S; Abraham, T Emilia



Structures of octenylsuccinylated starches: effects on emulsions containing ?-carotene.  


Starches with different amylopectin contents and different molecular sizes prepared using acid hydrolysis were hydrophobically modified using octenylsuccinic anhydride (OSA). The OSA-modified starches were used as surfactants to stabilize emulsions of ?-carotene and canola oil dispersed in water. The objective of this study is to investigate the relationship between starch molecular structure and the chemical stability of the emulsified ?-carotene, as well as the colloidal stability of emulsion droplets during storage. The oil droplet size in emulsions was smaller when starch had (a) lower hydrodynamic volume (Vh) and (b) higher amylopectin content. The oxidative stability of ?-carotene was similar across samples, with higher results at increased amylopectin content but higher Vh. Steric hindrance to coalescence provided by adsorbed OSA-modified starches appears to be improved by more rigid molecules of higher degree of branching. PMID:25129720

Sweedman, Michael C; Hasjim, Jovin; Schäfer, Christian; Gilbert, Robert G



Preamylopectin Processing: A Mandatory Step for Starch Biosynthesis in Plants.  

PubMed Central

It has been generally assumed that the [alpha]-(1->4)-linked and [alpha]-(1->6)-branched glucans of starch are generated by the coordinated action of elongation (starch synthases) and branching enzymes. We have identified a novel Chlamydomonas locus (STA7) that when defective leads to a wipeout of starch and its replacement by a small amount of glycogen-like material. Our efforts to understand the enzymological basis of this phenotype have led us to determine the selective disappearance of an 88-kD starch hydrolytic activity. We further demonstrate that this enzyme is a debranching enzyme. Cleavage of the [alpha]-(1->6) linkage in a branched precursor of amylopectin (preamylopectin) has provided us with the ground rules for understanding starch biosynthesis in plants. Therefore, we propose that amylopectin clusters are synthesized by a discontinuous mechanism involving a highly specific glucan trimming mechanism. PMID:12239416

Mouille, G.; Maddelein, M. L.; Libessart, N.; Talaga, P.; Decq, A.; Delrue, B.; Ball, S.



Plasticized-starch/poly(ethylene oxide) blends prepared by extrusion.  


Blends based on plasticized-wheat starch (as matrix or rich phase) and poly(ethylene oxide) (PEO) (as dispersed phase) were prepared by melt processing in a twin-screw extruder. The extrusion of the plasticized-starch is significantly facilitated by blending with PEO. Plasticized-starch and PEO are immiscible in the range of the investigated blend ratios (90/10-50/50). The phase inversion takes place when the PEO content is 50 wt.% in the blend. Both the thermal stability and the tensile properties of plasticized-starch are improved by blending with PEO. Also, a synergistic effect between plasticized-starch and PEO is noticed at 25-40 wt.% PEO content in the blend, the Young's modulus of the materials obtained being the highest and higher than both neat polymer components at those blending ratios. PMID:23044130

Yu, Fang; Prashantha, Kalappa; Soulestin, Jeremie; Lacrampe, Marie-France; Krawczak, Patricia



Color Burst  

NSDL National Science Digital Library

This lesson will help students gain experience in asking questions and conducting inquiry by exploring the separation of colors in water and other solvents; and to communicate and share findings of student investigations. The lesson uses a technique called paper chromatography, which is demonstrated using water, ink, and a coffee filter. Scientists use chromatography frequently to separate and identify the component parts of a mixture. This lesson will help young students gain experience in conducting simple investigations of their own while working in small groups.


Reactivation of meristem activity and sprout growth in potato tubers require both cytokinin and gibberellin.  


Reactivation of dormant meristems is of central importance for plant fitness and survival. Due to their large meristem size, potato (Solanum tuberosum) tubers serve as a model system to study the underlying molecular processes. The phytohormones cytokinins (CK) and gibberellins (GA) play important roles in releasing potato tuber dormancy and promoting sprouting, but their mode of action in these processes is still obscure. Here, we established an in vitro assay using excised tuber buds to study the dormancy-releasing capacity of GA and CK and show that application of gibberellic acid (GA(3)) is sufficient to induce sprouting. In contrast, treatment with 6-benzylaminopurine induced bud break but did not support further sprout growth unless GA(3) was administered additionally. Transgenic potato plants expressing Arabidopsis (Arabidopsis thaliana) GA 20-oxidase or GA 2-oxidase to modify endogenous GA levels showed the expected phenotypical changes as well as slight effects on tuber sprouting. The isopentenyltransferase (IPT) from Agrobacterium tumefaciens and the Arabidopsis cytokinin oxidase/dehydrogenase1 (CKX) were exploited to modify the amounts of CK in transgenic potato plants. IPT expression promoted earlier sprouting in vitro. Strikingly, CKX-expressing tubers exhibited a prolonged dormancy period and did not respond to GA(3). This supports an essential role of CK in terminating tuber dormancy and indicates that GA is not sufficient to break dormancy in the absence of CK. GA(3)-treated wild-type and CKX-expressing tuber buds were subjected to a transcriptome analysis that revealed transcriptional changes in several functional groups, including cell wall metabolism, cell cycle, and auxin and ethylene signaling, denoting events associated with the reactivation of dormant meristems. PMID:21163959

Hartmann, Anja; Senning, Melanie; Hedden, Peter; Sonnewald, Uwe; Sonnewald, Sophia



Relation between the tritium in continuous atmospheric release and the tritium contents of fruits and tubers.  


Concentrations of organically bound tritium (OBT) and tissue-free water tritium (TFWT, also referred to as HTO) in fruits and tubers were measured at a garden plot in the vicinity of the source of chronic airborne tritium emissions during the 2008, 2010, and 2011 growing seasons. A continuous record of HTO concentration in the air moisture was reconstructed from the continuous record of Ar-41 ambient gamma radiation, as well as from frequent measurements of air HTO by active samplers at the garden plot and Ar-41 and air HTO monitoring data from the same sector. Performed measurements were used for testing the modified Specific Activity (SA) model based on the assumption that the average air HTO during the pod-filling period provides an appropriate basis for estimating the levels of OBT present in pods, fruits and tubers. It is established that the relationship between the OBT of fruits and tubers and the average air HTO from a 15-20 day wide window centred at the peak of the pod-filling period is consistent throughout the three analysed years, and could be expressed by the fruit or tuber's OBT to air-HTO ratio of 0.93 ± 0.21. For all three years, the concentration of HTO in fruits and tubers was found to be related to levels of HTO in the air, as averaged within a 3-day pre-harvest window. The variability in the ratio of plant HTO to air HTO appears to be three times greater than that for the OBT of the fruits and tubers. It is concluded that the OBT of fruits and tubers adequately follows an empirical relationship based on the average level of air HTO from the pod-filling window, and therefore is clearly in line with the modified SA approach. PMID:23337314

Korolevych, V Y; Kim, S B



Cognitive aspects of color  

NASA Astrophysics Data System (ADS)

This report surveys cognitive aspects of color in terms of behavioral, neuropsychological, and neurophysiological data. Color is usually defined as psychophysical color or as perceived color. Behavioral data on categorical color perception, absolute judgement of colors, color coding, visual search, and visual awareness refer to the more cognitive aspects of color. These are of major importance in visual synthesis and spatial organization, as already shown by the Gestalt psychologists. Neuropsychological and neurophysiological findings provide evidence for an interrelation between cognitive color and spatial organization. Color also enhances planning strategies, as has been shown by studies on color and eye movements. Memory colors and the color- language connections in the brain also belong among the cognitive aspects of color.

Derefeldt, Gunilla A. M.; Menu, Jean-Pierre; Swartling, Tiina



Learning About Color  

NSDL National Science Digital Library

In this project, students will learn about primary, secondary, and complementary colors. Students will also learn about warm & cool colors, along with tints & shades. Lastly, they will create an optical illusion using complimentary colors. INTRODUCTION: Welcome students! Begin by watching this fun video about colors. LEARNING ABOUT COLOR: Now, that you've had an introduction to colors, lets play a little game! Click on the link below. Carmine s Introduction to Color Awesome! Click on the links below ...

Whitni Erickson



Color Theory for Design  

NSDL National Science Digital Library

This lesson will introduce students to color theory with a focus on the use of color in digital design. Students will discover the color wheel, and color harmonies. Color is a very powerful tool in design. It can, enhance a message, give an object visual weight and emphasis, and add richness and depth to a design. We can use color to signify data, to draw attention to a particular object, or to set a mood. Color ...

Mr. Jensen



Phylogeny and phylogeography of the Tuber brumale aggr.  


The Tuber brumale (winter truffle) is a black truffle reported from most European countries, belonging to the Melanosporum group. Its significance in the economy is ambivalent as the winter truffle has been shown to be a frequent contaminant species in the orchards of the Perigord truffle and occasionally in those of the summer truffle, yet owing to its delicate fragrance, its trade is worthy of note. The phylogeny and phylogeography of economically important truffles are relatively well-explored; however, no thorough research has been published on these aspects of the winter truffle. Therefore, here, we report the first phylogeographic analyses based on samples representing the entire distribution of the species. ITS sequences were used in this survey for haplotype and coalescent analyses, while phylogenetic analyses were based on the ITS, LSU and PKC loci. According to all loci, the samples clustered into two big clades imply the existence of two phylogenetic species. Based on our results, one of these appears to be endemic to the Carpathian Basin. In the other more widespread species, two main phylogeographic groups can be distinguished that show east-west separation with a zone of overlap in the Carpathian Basin, suggesting that they survived the latest glacial period in separate refugia. PMID:24604084

Merényi, Zsolt; Varga, Torda; Geml, József; Orczán, Ákos Kund; Chevalier, Gerard; Bratek, Zoltán



Green biosynthesis of silver nanoparticles using Curcuma longa tuber powder  

PubMed Central

Green synthesis of noble metal nanoparticles is a vastly developing area of research. Metallic nanoparticles have received great attention from chemists, physicists, biologists, and engineers who wish to use them for the development of a new-generation of nanodevices. In this study, silver nanoparticles were biosynthesized from aqueous silver nitrate through a simple and eco-friendly route using Curcuma longa tuber-powder extracts, which acted as a reductant and stabilizer simultaneously. Characterizations of nanoparticles were done using different methods, which included ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray fluorescence spectrometry, and Fourier-transform infrared spectroscopy. The ultraviolet-visible spectrum of the aqueous medium containing silver nanoparticles showed an absorption peak at around 415 nm. Transmission electron microscopy showed that mean diameter and standard deviation for the formation of silver nanoparticles was 6.30 ± 2.64 nm. Powder X-ray diffraction showed that the particles are crystalline in nature, with a face-centered cubic structure. The most needed outcome of this work will be the development of value-added products from C. longa for biomedical and nanotechnology-based industries. PMID:23341739

Shameli, Kamyar; Ahmad, Mansor Bin; Zamanian, Ali; Sangpour, Parvanh; Shabanzadeh, Parvaneh; Abdollahi, Yadollah; Zargar, Mohsen



Solanum Tuber-bearing Species Resistance Behavior Against Nacobbus aberrans  

PubMed Central

Naccobus aberrans is a major pest of the potato crop in the Andean regions of Argentina, Bolivia, and Perú. It is endemic in northwest Argentina and is also found in lowlands. The resistance of eleven Andean potato landraces and three accessions of the wild tuber-bearing species Solanum acaule, S. infundibuliforme, and S. megistacrolobum were evaluated against a population of N. aberrans from Coctaca, Jujuy province, while Solanum tuberosum ssp. tuberosum ‘Spunta’, ‘Kennebec’, and ‘Frital INTA’ were evaluated against a population from the southeast of Buenos Aires province. The presence, the number of galls, and the number of individuals were recorded. In addition, a reproduction factor was calculated and races were determined. Results showed that the N. aberrans population from Coctaca corresponded to race 2 and the population from the lowlands belonged to the sugar beet group. Landrace Azul, one genotype of S. megistacrolobum, and two genotypes of S. acaule showed resistance towards the race from Coctaca while no infection was recorded in potato cultivars with the Naccobus race from the lowland area. PMID:22661771

Chaves, Eliseo J.; Clausen, Andrea. M.; Franco, Javier



Antiallergic phenanthrenes and stilbenes from the tubers of Gymnadenia conopsea.  


The methanolic extract from the tubers of Gymnadenia conopsea showed an antiallergic effect on ear passive cutaneous anaphylaxis reactions in mice. From the methanolic extract, three new dihydrophenanthrenes, gymconopins A ( 1), B ( 2), and C ( 3), and a new dihydrostilbene, gymconopin D ( 4), were isolated together with 10 known phenanthrene and stilbene constituents. The structures of the new compounds were determined on the basis of physicochemical evidence. Next, the inhibitory effects of the principal constituents on the release of beta-hexosaminidase, as a marker of degranulation, in RBL-2H3 cells were examined and five phenanthrenes, gymconopin B ( 2), 4-methoxy-9,10-dihydrophenanthrene-2,7-diol ( 6), 1-(4-hydroxybenzyl)-4-methoxyphenanthrene-2,7-diol ( 7), 1-(4-hydroxybenzyl)-4-methoxy-9,10-dihydrophenanthrene-2,7-diol ( 8), and blestriarene A ( 9), and six dihydrostilbenes, gymconopin D ( 4), batatacin III ( 10), 3'- O-methylbatatacin III ( 11), 3,3'-dihydroxy-2-(4-hydroxybenzyl)-5-methoxybibenzyl ( 12), 3',5-dihydroxy-2-(4-hydroxybenzyl)-3-methoxybibenzyl ( 13), and 3,3'-dihydroxy-2,6-bis(4-hydroxybenzyl)-5-methoxybibenzyl ( 14) were found to inhibit the antigen-induced degranulation by 65.5 to 99.4 % at 100 microM in RBL-2H3 cells. PMID:15386193

Matsuda, Hisashi; Morikawa, Toshio; Xie, Haihui; Yoshikawa, Masayuki



Starch Utilization by Ruminants: From Basics to the Bunk1,2  

Microsoft Academic Search

Starch is the major energy component of grains. Wheat contains 77% of DM as starch, corn and sorghum contain 72%, and barley and oats contain 57 to 58%. In vitro systems have provided valuable data on kinetic aspects of starch digestion. Molecular biological techniques have provided a clearer picture of the ruminal microbial milieu. Proportions of starch fermented in the

Gerald B. Huntington



Processing, performance and biodegradability of a thermoplastic aliphatic polyester\\/starch system  

Microsoft Academic Search

Composites of a biodegradable thermoplastic aliphatic polyester, polybutylene succinate adipate (PBSA), with granular corn starch were investigated for processability, mechanical and thermal properties, and biodegradability. The PBSA\\/starch films were prepared with starch contents of 5%–30% by weight and processed by blown film extrusion. Increasing the starch content led to an increase in modulus and decreases in tensile strength, elongation to

Jo Ann Ratto; Peter J. Stenhouse; Margaret Auerbach; John Mitchell; Richard Farrell



Influence of starch source on sporulation and enterotoxin production by Clostridium perfringens type A.  


Of 16 different starch preparations tested, Clostridium perfringes NCTC 8798 yielded maximum sporulation and enterotoxin formation when ICN-soluble starch was included in Duncan and Strong sporulation medium. In general soluble starches were better than potato, corn, or arrowroot starch with regard to these two parameters. PMID:180885

Labbe, R; Somers, E; Duncan, C



Chemical composition, mineral profile, and functional properties of Canna (Canna edulis) and Arrowroot (Maranta spp.) starches.  


The aim of the present study was to evaluate some chemical and mineral characteristics and functional and rheological properties of Canna and Arrowroot starches produced in the Venezuelan Andes. Canna starch showed a higher (P < 0.05) moisture, ash, and crude protein content than arrowroot starch, while crude fiber, crude fat, and amylose content of this starch were higher (P < 0.05). Starches of both rhizomes own phosphorus, sodium, potassium, magnesium, iron, calcium, and zinc in their composition. Phosphorus, sodium, and potassium are the higher in both starches. Water absorption, swelling power, and solubility values revealed weak bonding forces in Canna starch granules; this explained the lower gelatinization temperature and the substantial viscosity development of Canna starch during heating. Arrowroot starch showed a higher gelatinization temperature measure by DSC, than Canna starch and exhibited a lower value of DeltaH. Both starches show negative syneresis. The apparent viscosity of Canna starch was higher (P < 0.05) than the Arrowroot starch values. The size (wide and large) of Canna starch granules was higher than arrowroot starch. From the previous results, it can be concluded that Canna and Arrowroot starches could become interesting alternatives for food developers, depending on their characteristics and functional properties. PMID:16187013

Pérez, Elevina; Lares, Mary



Physical properties of starch granules of tobacco leaves during maturity stage  

Microsoft Academic Search

Although there are many studies concerning starch accumulation pattern of tobacco leaves during maturity stage (1, 2, 3, 4, 5), much less attention has been paid to physical properties of starch granules of tobacco leaves. Mathesonet al. (6) reported in their study of starch changes in developing and senescing tobacco leaves, that the viscosities and iodine affinities of isolated starch

Tatsuo Kakie




Technology Transfer Automated Retrieval System (TEKTRAN)

The boundary coefficient of friction (COF) of FanteskTM starch-oil composite dry film lubricants was investigated as a function of starch chemistry (waxy vs. normal purified food grade corn starch), oil chemistry (hexadecane vs. oleic acid and various vegetable oils), and starch-to-oil ratio. Based...


New starches from traditional Chinese medicine (TCM)—Chinese yam ( Dioscorea opposita Thunb.) cultivars  

Microsoft Academic Search

The starches separated from two different Dioscorea opposita Thunb. cultivars were investigated for morphological, thermal and crystal properties. The shape of starch granules separated from different D. opposita Thunb. cultivars varied from round to oval or irregular. The surface of the starch granules appeared to be smooth without any fissures. The average particle diameter of starches from different D. opposita

Wang Shujun; Yu Jinglin; Gao Wenyuan; Liu Hongyan; Xiao Peigen



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

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Characterization of gelatinized corn starch suspensions and resulting drop size distributions after effervescent atomization  

Microsoft Academic Search

Effervescent atomization is a promising method for economical atomization of high viscous liquids like gelatinized corn starch suspensions. The gelatinization of starch has strong influence on the viscosity of starch suspensions. It was characterized adapting a method for determination of the gelatinization degree. Rheological properties of gelatinized corn starch suspensions with concentrations ranging from 5 to 7wt.-% were investigated. Effervescent

Jewe Schröder; Stefan Kraus; Bruna Bertolla Rocha; Volker Gaukel; Heike P. Schuchmann



Chemical compositions, fine structure and physicochemical properties of kudzu ( Pueraria lobata) starches from different regions  

Microsoft Academic Search

Three commercial kudzu starches from Vietnam, Japan and Korea were used to determine chemical compositions, isoflavone compounds, fine structure and physicochemical properties. The kudzu starch from Vietnam had polygonal granules, whereas the kudzu starches from Japan and Korea contained both polygonal and spherical granules. Total protein, lipid, ash and phosphorus contents present in these kudzu starches were less than 1%

Pham Van Hung; Naofumi Morita



Slowly digestible starch diets alter proximal glucosidase activity and glucose absorption  

Technology Transfer Automated Retrieval System (TEKTRAN)

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...


Sago starch and composition of associated components in palms of different growth stages  

Microsoft Academic Search

Sago (Metroxylon sagu) starch accumulates in the pith of the sago palm stem from the base upwards. At maturity, the trunk is fully saturated with starch almost to the crown. Apart from sago starch granules, the pith also contained other associated components. The starch content and composition of associated components at five different growth stages of sago palm have been

A. T. Pei-Lang; A. M. D. Mohamed; A. A. Karim



Structural Properties of Starch in Bread and Bread Model Systems: Influence of an Antistaling ?-Amylase  

Microsoft Academic Search

Cereal Chem. 78(4):421-428 The influence of an antistaling ?-amylase on bread crumb and on wheat starch gels was investigated taking into account different levels of struc- tural hierarchy. Bread was prepared by a conventional baking procedure. Starch gels were produced by heating a concentrated starch dispersion in closed molds. Bread and starch gels were characterized by compression tests, light microscopy

S. Hug-Iten; F. Escher; B. Conde-Petit



Tuberous sclerosis diagnosed by incidental computed tomography findings of multifocal micronodular pneumocyte hyperplasia: a case report  

PubMed Central

Introduction The majority of multifocal micronodular pneumocyte hyperplasia associated with tuberous sclerosis complex is diagnosed with the classical clinical triad of seizures, mental retardation, and skin lesions. We report a rare case of tuberous sclerosis complex with no classical clinical findings, which was diagnosed through incidental computed tomography findings of multiple nodular lesions of multifocal micronodular pneumocyte hyperplasia. Case presentation A chest computed tomography scan of a 51-year-old Japanese woman showed multiple nodular ground-glass opacities that were not seen on chest X-ray. Video-assisted thoracoscopic surgery was performed. A histological examination demonstrated type II pneumocyte hyperplasia with thickened fibrotic alveolar septa, which was consistent with multifocal micronodular pneumocyte hyperplasia. Brain magnetic resonance imaging displayed multiple cortical tubers, and abdominal computed tomography showed bilateral renal angiomyolipoma. Our patient was finally diagnosed as having tuberous sclerosis complex with multifocal micronodular pneumocyte hyperplasia, although she had no episodes of epilepsy, no skin lesions, and no family history. Conclusions Multifocal micronodular pneumocyte hyperplasia with latent tuberous sclerosis complex should be considered in the differential diagnosis of multiple ground-glass opacities. PMID:23072249



Gibberellin A1 Metabolism Contributes to the Control of Photoperiod-Mediated Tuberization in Potato  

PubMed Central

Some potato species require a short-day (SD) photoperiod for tuberization, a process that is negatively affected by gibberellins (GAs). Here we report the isolation of StGA3ox2, a gene encoding a GA 3-oxidase, whose expression is increased in the aerial parts and is repressed in the stolons after transfer of photoperiod-dependent potato plants to SD conditions. Over-expression of StGA3ox2 under control of constitutive or leaf-specific promoters results in taller plants which, in contrast to StGA20ox1 over-expressers previously reported, tuberize earlier under SD conditions than the controls. By contrast, StGA3ox2 tuber-specific over-expression results in non-elongated plants with slightly delayed tuber induction. Together, our experiments support that StGA3ox2 expression and gibberellin metabolism significantly contribute to the tuberization time in strictly photoperiod-dependent potato plants. PMID:21961036

Bou-Torrent, Jordi; Martínez-García, Jaime F.; García-Martínez, José Luis; Prat, Salomé



Molecular detection of potato spindle tuber viroid in Razavi and Northern Khorasan provinces.  


The aim of this study was to identify the Potato Spindle Tuber Viroid (PSTVd) by Reverse Transcriptase-PCR. Among all plant diseases which are caused by viroids, PSTVd was the first viroid which is recognized by plant pathologist. Suspended potato tubers from Razavi and Northern Khorasan provinces collected and cultured. Leaves of cultured tubers were used for RNA extraction by PEG6000 Precipitation method. Subsequent RT-PCR reaction has been carried out using specific primers. A 359 bp fragment has been appeared after electrophoresis which has not appeared in healthy tuber samples. Digestion of obtained fragment with BamHI confirmed the sequence by producing two fragments of 119 and 240 bp. Sequencing has been done to certify the PSTVd. The sequencing result showed that infection in tested areas is caused by mild strain of PSTVd. In this project from 250 samples, 14 tubers were infected. This was the first report of occurrence of mild strain of PSTVd in Iran. PMID:18819657

Arezou, Yazarlou; Jafarpour, Behrouz; Rastegar, Mahrokh Falahati; Javadmanesh, Ali



Disruptive Coloration  

NSDL National Science Digital Library

Most animals are patterned. While some markings may serve as an advertisement, many appear to function in concealment. Because of the principal way in which they seem to function, such markings are often termed disruptive coloration . Although there are a number of characteristics that may influence the effectiveness of markings in disruption; this study will only focus on two aspects: (1) the effectiveness of the position of markings in blurring or enhancing outline, and (2) the degree to which strongly contrasting markings may interfere with or aid recognition. In regard to the former, it must be kept in mind that the profile changes with change in viewing angle. Thus the pattern seen in relation to the profile most commonly presented to predator (or prey) is of most interest to us here.

David Ipsen



COLORS Magazine  

NSDL National Science Digital Library

COLORS Magazine was willed into existence in 1991 by photographer Oliviero Toscani and art director Tibor Kalman. Its goal was simple: "to show the world to the world.� The publication looks at social issues around the world through thoughtful prose and meaningful visuals. Visitors can click on the Stories tab to click through a visual field of photos that lead to such stories as military service in South Korea and cuts to public spending in the United Kingdom. The Notebooks area brings together commentaries from all over the world as part of a collaboration with Reporters sans Frontieres. The Projects area contains links to special issues and projects, such as the News Machine that "churns your tweets through different media filters.� Interested users can learn about obtaining a print subscription or explore the corresponding blog.


Gravitropism in roots of intermediate-starch mutants of Arabidopsis  

NASA Technical Reports Server (NTRS)

Gravitropism was studied in roots of wild type (WT) Arabidopsis thaliana (L.) Heynh. (strain Wassilewskija) and three starch-deficient mutants that were generated by T-DNA insertional mutagenesis. One of these mutants was starchless while the other two were intermediate mutants, which had 51% and 60%, respectively, of the WT amount of starch as determined by light and electron microscopy. The four parameters used to assay gravitropism were: orientation during vertical growth, time course of curvature, induction, and intermittent stimulation experiments. WT roots were much more responsive to gravity than were roots of the starchless mutant, and the intermediate starch mutants exhibited an intermediate graviresponse. Our data suggest that lowered starch content in the mutants primarily affects gravitropism rather than differential growth because both phototropic curvature and growth rates were approximately equal among all four genotypes. Since responses of intermediate-starch mutants were closer to the WT response than to the starchless mutant, it appears that 51-60% of the WT level of starch is near the threshold amount needed for full gravitropic sensitivity. While other interpretations are possible, the data are consistent with the starch statolith hypothesis for gravity perception in that the degree of graviresponsiveness is proportional to the total mass of plastids per cell.

Kiss, J. Z.; Wright, J. B.; Caspar, T.



Colors and Shapes  

NSDL National Science Digital Library

How do you name things by color and shape? Lets learn about shapes and colors! 1. Watch this Color Video 2. Play this Color Game 3. Complete this Color Page 4. Watch this Shape Video 5. Watch this Shape Video2 6. Play this Shape Game 7. ...




Similarity of Color Images  

Microsoft Academic Search

We describe two new color indexing techniques. The first one is a more robust version of thecommonly used color histogram indexing. In the index we store the cumulative color histograms.The L 1 -, L 2 -, or L1 -distance between two cumulative color histograms can be used to define asimilarity measure of these two color distributions. We show that while

Markus A. Stricker; Markus Orengo



Disappearing Colors Crayola Supplies  

E-print Network

· · Social Studies Visual Arts · · Why Experiment with color perception by making your own color filter on the lens color. 2. Design your own experiment. Draw patterns of lines and shapes using Crayola to see how looking through different colored plastic wrap affects your perception of colorful patterns

Zanibbi, Richard


Crystallization and chain reorganization of debranched rice starches in relation to resistant starch formation.  


The effects of chain distribution, concentration, temperature and hydrothermal treatments on the recrystallization behavior and formation of resistant starch (RS) were investigated. Waxy and normal rice starches were debranched at 10 and 21% w/w solid concentrations, incubated at 25 or 50°C, and further subjected to annealing or heat moisture treatment (HMT) to enhance RS formation. The crystallization at 25°C favored the formation of the B-type structure, whereas crystallization at 50°C led to the A-type structure with a higher melting temperature (100-120°C) and a higher RS content (52%). All incubated samples showed an increase in RS content after subsequent hydrothermal treatments. The sample incubated at a high temperature contained the highest RS content (74.5%) after HMT with larger/perfect crystallites. These results suggested that the RS formation could be manipulated by crystallization conditions and improved by hydrothermal treatments which are dependent on the initial crystalline perfection. PMID:25817649

Kiatponglarp, Worawikunya; Tongta, Sunanta; Rolland-Sabaté, Agnès; Buléon, Alain