Properties of starch from potatoes differing in glycemic index

Starch from a low glycemic index (GI) potato cultivar (Carisma, shown in the ESEM image) was more resistant to hydrothermal treatment than other potato starches, but was not differentiated from the other starches by granule size distribution, amylose and P contents, and amylopectin chain length distribution.

Download Full-text

Expression of bacterial starch-binding domains in Arabidopsis increases starch granule size

Functional Plant Biology ◽

10.1071/fp05277 ◽

2006 ◽

Vol 33 (3) ◽

pp. 257 ◽

Cited By ~ 6

Author(s):

Crispin A. Howitt ◽

Sadequr Rahman ◽

Matthew K. Morell

Keyword(s):

Starch Granule ◽

Starch Content ◽

Starch Synthesis ◽

Length Distribution ◽

Renewable Resource ◽

Granule Size ◽

Parental Line ◽

In Planta ◽

Chain Length Distribution ◽

Binding Domains

Starch is a readily renewable resource that is very widely used for food and industrial purposes; however, greater variation in the functional properties of starch would further extend the use of this biodegradable polymer. Genetic engineering may provide a way to produce designer starches that have the desired properties. Starch-binding domains (SBD) from bacterial enzymes that catabolise starches have the ability to bind two helices of starch and thus have the potential to crosslink starch and / or to be used as anchors for other enzymes that can modify starch properties. In a first step towards novel modification of starch we have investigated the effect of expressing SBDs, singly and in tandem, in planta, and targeting them to the chloroplast in the model plant Arabidopsis thaliana (L.) Heynh. Transgenic plants that contained the SBD from the cyclomaltodextrin glucanotransferase (CGTase) of Thermoanaerobacterium thermosulfurigenes in the chloroplast were produced in both the wild type and the starch excess mutant (sex 1-1) backgrounds. Analysis of starch isolated from the chloroplasts of these lines revealed no significant changes in the amylose : amylopectin ratio, the chain-length distribution of debranched amylopectin or the gelatinisation temperature when compared to the parental line. However, significant changes were observed in the starch granule size with the plants expressing the construct having larger granules. The effect was more pronounced in the sex 1-1 background, and expression of two starch-binding domains linked in tandem had an even greater effect. Despite the starch granules being larger in lines expressing the starch-binding domain, no difference was seen in the starch content of the leaves when compared to parental lines. As the presence of the SBDs in the starch granule only altered granule size, and not other granule properties, they may provide an ideal anchor for targeting starch-modifying enzymes to the site of starch synthesis. This will allow the development of novel modifications of starch during synthesis.

Download Full-text

Molecular Simulations of Tilted Chain Crystal - Amorphous Interfaces in Polymers

MRS Proceedings ◽

10.1557/proc-586-49 ◽

1999 ◽

Vol 586 ◽

Author(s):

S. Gautam ◽

S. Balijepalli ◽

G. C. Rutledge

Keyword(s):

Length Distribution ◽

Molecular Simulations ◽

Polymeric Materials ◽

Polymer Chains ◽

The Other ◽

Interfacial Structure ◽

Distribution Model ◽

Structure And Properties ◽

Molecular Connectivity ◽

Chain Length Distribution

ABSTRACTSemi-crystalline polymeric materials exhibit metastable interfaces which must simultaneously feature molecular connectivity through chain bonding and disorder across the interface. To address this, off lattice molecular simulations have been constructed to capture the structure and properties of crystal-amorphous interfaces in polyethylene with freely rotating chains. Monte-Carlo simulations were performed on systems having {001 }, {201} and {502} interfaces (polymer chains tilted to the lamella normal by 0°, 34.4° and 41° respectively.)Results of the simulations reveal changes in interfacial structure with variation in the chain-tilt angle. The degree of tight folding decreases with increasing tilt, from predominantly [110] loops in the {001} interface to [200] and [310] loops on the other interfaces. The topology shifts towards an increase in loosely folded loops along with longer bridges and tails. The results also compare well with a Gaussian chain length distribution model. The {201} interface exhibits the lowest interfacial energy, in apparent agreement with experimental data.

Download Full-text

Modeling and Sensitivity Analysis of Particle Size Distribution and Chain Length Distribution in a Semibatch Emulsion Copolymerization Reactor

Macromolecular Theory and Simulations ◽

10.1002/mats.200500019 ◽

2005 ◽

Vol 14 (8) ◽

pp. 474-490 ◽

Cited By ~ 8

Author(s):

Myung-June Park ◽

Mustafa T. Dokucu ◽

Francis J. Doyle

Keyword(s):

Sensitivity Analysis ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Chain Length ◽

Length Distribution ◽

Chain Length Distribution ◽

Emulsion Copolymerization

Download Full-text

Origin of defects in assembled supramolecular structures of sweet potato starches with different amylopectin chain-length distribution

Carbohydrate Polymers ◽

10.1016/j.carbpol.2008.10.029 ◽

2009 ◽

Vol 76 (3) ◽

pp. 400-409 ◽

Cited By ~ 29

Author(s):

Takahiro Noda ◽

Naoto Isono ◽

Alexey V. Krivandin ◽

Olga V. Shatalova ◽

Wioletta Błaszczak ◽

...

Keyword(s):

Sweet Potato ◽

Chain Length ◽

Length Distribution ◽

Supramolecular Structures ◽

Chain Length Distribution ◽

Potato Starches

Download Full-text

THE recipe modification of sugar-free bakery goods for reducing glycemic index and enhancing the nutrition and functional features

International Conference on Technics Technologies and Education ◽

10.15547/ictte.2019.07.028 ◽

2019 ◽

pp. 463-468

Author(s):

Nataliia Sokolova

Keyword(s):

Glycemic Index ◽

Metabolic Disorders ◽

Healthy Lifestyle ◽

Optimum Ratio ◽

Medical Problems ◽

Rye Flour ◽

Lentil Flour ◽

Functional Features ◽

Baked Products ◽

Low Glycemic Index

Wheat flour-based products are the most popular and desirable of all bakery goods. In the same time, they give the heights glycemic response so this type of products are banned for people with metabolic disorders as well as consumers who have a tendency to live a healthy lifestyle. In the same time the increasing consumption of sugars has resulted in several nutritional and medical problems, such as obesity, diabetes, and cardiovascular diseases. The uses of a combination of various ingredients in range (such as rye flour – 40...60, dry gluten – 5...15, oat dietary fibre – 1...6 % and lentil flour - 5...20 %) that may modify the glycemic index of baked products, enhance the nutrition and functional features have shown in the article. Water Stevia extract demonstrated no effect on the baking quality and suggested the use of it to improve palatability and nutritional properties of developed new sugar-free bakery products. It was found the optimum ratio of these ingredients as a result of a series of studies and processing of the obtained data by multicriteria optimization. Results have shown that lentil flour can be used in the amount 12.5 % for the achieving optimum ratio "low glycemic index-high taste". It is shown that due to lentil flour it is possible to reduce the glycemic index to a greater extent than rye flour, dry gluten, but in terms of the taste characteristics, these products were less attractive with an increasing amount of flour in formula. The coefficients of the regression model were given as a result, it has helped to find out the patterns of influence of selected components and their dosage on the glycemic index, energy value and sensory characteristics of the product. The article represents the results, which can be used to create recipe compositions using selected ingredients.

Download Full-text

Direct Observation of Chain Lengths and Conformations in Oligofluorene Distributions from Controlled Polymerization by Double Electron-Electron Resonance

10.26434/chemrxiv.10002785 ◽

2019 ◽

Author(s):

Dennis Bücker ◽

Annika Sickinger ◽

Julian D. Ruiz Perez ◽

Manuel Oestringer ◽

Stefan Mecking ◽

...

Keyword(s):

Chain Length ◽

Length Distribution ◽

Catalyst System ◽

Chain Conformation ◽

Controlled Polymerization ◽

Chain Length Distribution ◽

Electron Resonance ◽

Double Electron ◽

The Individual ◽

Double Electron Electron Resonance

Synthetic polymers are mixtures of different length chains, and their chain length and chain conformation is often experimentally characterized by ensemble averages. We demonstrate that Double-Electron-Electron-Resonance (DEER) spectroscopy can reveal the chain length distribution, and chain conformation and flexibility of the individual n-mers in oligo-(9,9-dioctylfluorene) from controlled Suzuki-Miyaura Coupling Polymerization (cSMCP). The required spin-labeled chain ends were introduced efficiently via a TEMPO-substituted initiator and chain terminating agent, respectively, with an in situ catalyst system. Individual precise chain length oligomers as reference materials were obtained by a stepwise approach. Chain length distribution, chain conformation and flexibility can also be accessed within poly(fluorene) nanoparticles.

Download Full-text