Liver transplantation for type IV glycogen storage disease

TYPE IV glycogen storage disease is a rare autosomal recessive disorder (also called Andersen's disease1 or amylopectinosis) in which the activity of branching enzyme alpha-1, 4-glucan: alpha-1, 4-glucan 6-glucosyltransferase is deficient in the liver as well as in cultured skin fibroblasts and other tissues.2,3 This branching enzyme is responsible for creating branch points in the normal glycogen molecule. In the relative or absolute absence of this enzyme, an insoluble and irritating form of glycogen, an amylopectin-like polysaccharide that resembles plant starch, accumulates in the cells. The amylopectin-like form is less soluble than normal glycogen, with longer outer and inner chains. © 1991, Massachusetts Medical Society. All rights reserved

Comparison of Short-grain Rice Cultivars Grown in Japan and the United States

Although short-grain rice accounts for less than 2% of U.S. rice production, the demand for short-grain rice is expected to increase because of the increasing popularity of sushi and sake. The objective of this study was to compare the physical, chemical and textural properties of short-grain rice cultivars grown in Japan and in the U.S. Seven short-grain rice cultivars from the 2016 crop year were collected, including five cultivars (Hatsushimo, Kinuhikari, Koshihikari, Nanatsuboshi, and Yumepirika) grown and purchased in grocery stores in Japan, one (RU9601099) grown in Arkansas, and one (CH-202) grown in California. The rice cultivars were characterized for kernel dimensions, color, chemical composition, amylopectin fine structure, and gelatinization, pasting and textural properties. RU9601099 had a smaller kernel width and a greater whiteness (L*) value than the other cultivars. Japanese cultivars were comparable in protein content, while RU9601099 had the greatest and CH-202 had the lowest protein content. RU9601099, CH-202 and Kinuhikari shared a similar value of average amylopectin chain length and gelatinization temperatures and enthalpy, which were significantly greater than the other cultivars. Kinuhikari and RU9601099 displayed greater peak and trough viscosities, whereas Hatsushimo and Nanatsuboshi had lower peak and breakdown viscosities. When cooked, the Japanese cultivars exhibited significantly greater hardness than the U.S. cultivars. Based on Ward’s cluster analysis considering all data, CH-202 shared similar properties with Kinuhikari, and RU9601099 was distinctively different from the other cultivars in most properties. The information obtained from this study will help future cultivar development and marketing of existing short-grain rice cultivars in the U.S

Prediction of rice texture from starch profiles measured using high-performance liquid chromatography

Starch determines a large proportion of the textural properties of cooked rice. The amylose: amylopectin ratio plays a significant role in the functionality of native starch. In this study a medium-grain rice cultivar, ‘Bengal’, was used for starch structure characterization using high performance size-exclusion chromatography (HPSEC). This cultivar is characterized by having lower amylose content (15% to 20%) than long grain cultivars and being sticky when cooked, similar to short-grain cultivars. Rice samples were harvested in 1999 from five locations around Arkansas at state verification trials where cultural practices are closely monitored. Samples of this cultivar stored at a specified moisture level for a pre-determined period of time were also subjected to texture analysis by means of a Texture Analyzer. The data measured with the HPSEC was related to instrumental texture attributes. Chemical characterization data (carbohydrate profiles) of rice samples were used to predict texture attributes of cooked rice such as hardness and stickiness. Instrumental texture attributes of hardness and stickiness were successfully predicted for Bengal rice from starch-profile data obtained though HPSEC analyses. Both attributes proved to be well predicted, based on their high coefficients of determination of 0.97 and 0.85, respectively. The statistical analysis indicates that starch structure characterization using HPSEC may be related to instrumental measurements of texture attributes

Liver transplantation for type I and type IV glycogen storage disease

Progressive liver failure or hepatic complications of the primary disease led to orthotopic liver transplantation in eight children with glycogen storage disease over a 9-year period. One patient had glycogen storage disease (GSD) type I (von Gierke disease) and seven patients had type IV GSD (Andersen disease). As previously reported [19], a 16.5-year-old-girl with GSD type I was successfully treated in 1982 by orthotopic liver transplantation under cyclosporine and steroid immunosuppression. The metabolic consequences of the disease have been eliminated, the renal function and size have remained normal, and the patient has lived a normal young adult life. A late portal venous thrombosis was treated successfully with a distal splenorenal shunt. Orthotopic liver transplantation was performed in seven children with type N GSD who had progressive hepatic failure. Two patients died early from technical complications. The other five have no evidence of recurrent hepatic amylopectinosis after 1.1–5.8 postoperative years. They have had good physical and intellectual maturation. Amylopectin was found in many extrahepatic tissues prior to surgery, but cardiopathy and skeletal myopathy have not developed after transplantation. Postoperative heart biopsies from patients showed either minimal amylopectin deposits as long as 4.5 years following transplantation or a dramatic reduction in sequential biopsies from one patient who initially had dense myocardial deposits. Serious hepatic derangement is seen most commonly in types T and IV GSD. Liver transplantation cures the hepatic manifestations of both types. The extrahepatic deposition of abnormal glycogen appears not to be problematic in type I disease, and while potentially more threatening in type IV disease, may actually exhibit signs of regression after hepatic allografting

Physicochemical properties and leaching behavior of eight U.S. long-grain rice cultivars as related to rice texture

There are many long-grain rice cultivars produced commercially in the U.S.; however, little work has been done on correlating the structure and physicochemical properties of starch with their texture. The physicochemical properties, leaching behavior, and texture attributes of eight longgrain rice cultivars were studied. Differences were observed in the approximate composition of kernels, including crude protein (6.6-9.3%), crude lipid (0.18-0.51%), and apparent amylose content (25.5-30.9%). These cultivars also differed slightly in thermal properties, such as onset temperature (73.7° to 77.4°C) and peak temperature (78.8° to 81.9°C). Although they showed a similar pasting temperature, their peak viscosities ranged from 680 to 982 Brabender units. The amount and the molecular size distribution of the leached starch molecules varied greatly among the samples. The leached amylose, instead of the apparent amylose, was suggested to play an important role in cooked rice texture

Potential of the small-granule starch mutation for the Bioethanol Industry.

The industrial starch market is undergoing major expansion, but certain specific industrial uses cannot be satisfied by native starches and, therefore, chemical or physical modification is necessary. Mutations in the cassava starch biosynthesis pathways were discovered at CIAT (Cali, Colombia) few years ago. A starch mutation induced by gamma rays radiation resulted in a deeply modified branching pattern of amylopectin as well as other starch characteristics and properties. These modifications include changes in starch granule ultrastructure (e.g. decreased starch crystallinity), a weak organized structure, and increased susceptibility to mild acid and enzymatic raw starch hydrolysis (fastest and most efficient hydrolysis of all studied native starches). This mutation could offer interesting advantages for the production of bioethanol. Surprisingly this mutation also results in increased proportion of amylopectin. Hydrolysis was more dependent on granule morphology than on starch chemical composition. Recent crosses produced segregating progenies whose starch had the small-granule characteristics, but amylopectin content ranged from 19 to 42%. Rapid viscoamylograms of the latter starch showed very distinctive patterns. (Résumé d'auteur

Multi-scale structure, pasting and digestibility of adlay (Coixlachryma-jobi L.) seed starch

peer-reviewedThe hierarchical structure, pasting and digestibility of adlay seed starch (ASS) were investigated compared with maize starch (MS) and potato starch (PS). ASS exhibited round or polyglonal morphology with apparent pores/channels on the surface. It had a lower amylose content, a looser and more heterogeneous C-type crystalline structure, a higher crystallinity, and a thinner crystalline lamellae. Accordingly, ASS showed a higher slowly digestible starch content combined with less resistant starch fractions, and a decreased pasting temperature, a weakened tendency to retrogradation and an increased pasting stability compared with those of MS and PS. The ASS structure-functionality relationship indicated that the amylose content, double helical orders, crystalline lamellar structure, and surface pinholes should be responsible for ASS specific functionalities including pasting behaviors and in vitro digestibility. ASS showed potential applications in health-promoting foods which required low rearrangement during storage and sustainable energy-providing starch fractions

Genome editing in potato via CRISPR-Cas9 ribonucleoprotein delivery

Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein-9 (CRISPR-Cas9) can be used as an efficient tool for genome editing in potato (Solanum tuberosum). From both a scientific and a regulatory perspective, it is beneficial if integration of DNA in the potato genome is avoided. We have implemented a DNA-free genome editing method, using delivery of CRISPR-Cas9 ribonucleoproteins (RNPs) to potato protoplasts, by targeting the gene encoding a granule bound starch synthase (GBSS, EC 2.4.1.242). The RNP method was directly implemented using previously developed protoplast isolation, transfection and regeneration protocols without further adjustments. Cas9 protein was preassembled with RNA produced either synthetically or by in vitro transcription. RNP with synthetically produced RNA (cr-RNP) induced mutations, i.e. indels, at a frequency of up to 9%, with all mutated lines being transgene-free. A mutagenesis frequency of 25% of all regenerated shoots was found when using RNP with in vitro transcriptionally produced RNA (IVT–RNP). However, more than 80% of the shoots with confirmed mutations had unintended inserts in the cut site, which was in the same range as when using DNA delivery. The inserts originated both from DNA template remnants from the in vitro transcription, and from chromosomal potato DNA. In 2–3% of the regenerated shoots from the RNP-experiments, mutations were induced in all four alleles resulting in a complete knockout of the GBSS enzyme function.Fil: Andersson, Mariette. Swedish University Of Agricultural Sciences; SueciaFil: Turesson, Helle. Swedish University Of Agricultural Sciences; SueciaFil: Olsson, Niklas. Swedish University Of Agricultural Sciences; SueciaFil: Fält, Ann Sofie. Swedish University Of Agricultural Sciences; SueciaFil: Ohlsson, Pia. Swedish University Of Agricultural Sciences; SueciaFil: Gonzalez, Matías Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Samuelsson, Mathias. Lyckeby Starch AB; SueciaFil: Hofvander, Per. Swedish University Of Agricultural Sciences; Sueci

Safety evaluation of the food enzyme pullulanase from genetically modified Bacillus subtilis strain NZYM-AK

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Novel cassava starches with low and high amylose contents: Structural and macro-molecular characterization in comparison with other commercial sources

Cassava (Manihot esculenta Crantz) is one of the most important sources of commercial production of starch along with potato, maize and wheat particularly for tropical and subtropical regions of the world. It is the third most important source of calories in tropics, after rice and maize. Natural mutation, and induced ones in cassava starch have recently been reported leading to new starches with low and high-amylose contents (0 and 30-31 %). These mutants are drastically different from normal cassava starch whose amylose content typically ranges between 15-25 %. The aims of this study were to have an overview of the structural variability among the recently discovered cassava mutants comparatively to normal and amylose-free potato and maize starches. The macromolecular features, the crystallinity, the granule sizes, and the thermal properties of these new mutants were compared with five normal cassava starches (ranging from 16.8 to 21.5 % amylose) and commercial versions of amylose-free or normal potato and maize starch. The structure of cassava amylopectin was not modified by the waxy mutation and waxy cassava starch exhibited properties similar to the ones of waxy maize starch. Waxy cassava and maize amylopectins show similar molar masses and radii of gyration (from 408×106 g mol-1 to 520×106 g mol-1; and from 277 to 285 nm, respectively). Waxy potato amylopectin exhibit lower molar mass and size. Inversely, the higher-amylose mutations induced by gamma rays radiation in cassava, modified deeply the branching pattern of amylopectin as well as the starch characteristics and properties: molar masses and radii of gyration decreased, while branching degree increased. These modifications resulted in changes in starch granule ultrastructure (lowered starch crystallinity), a weak organized structure, and increased susceptibility to mild acid hydrolysis. The distinctive properties of the new cassava starches demonstrated in this article suggest new opportunities and commercial applications for these tropical sources of starch. (Résumé d'auteur