Studies on the Origin of Amylose and Amylopectin in Starch Granules. II. Changes in Amylose Content and Enzyme Activities in Cultures of Polytoma uvella

1970 ◽  
Vol 22 (10) ◽  
pp. 329-333 ◽  
Author(s):  
B. S. Mangat ◽  
N. P. Badenhuizen
Keyword(s):  
Enzyme Activities ◽  
Amylose Content ◽  
Starch Granules

Studies on the origin of amylose and amylopectin in starch granules. III. The effect of temperature on enzyme activities and amylose content

1971 ◽  
Vol 49 (10) ◽  
pp. 1787-1792 ◽  
Author(s):  
B. S. Mangat ◽  
N. P. Badenhuizen
Keyword(s):  
Enzyme Activities ◽  
Amylose Content ◽  
Starch Synthesis ◽  
Effect Of Temperature ◽  
Simultaneous Increase ◽  
Starch Granules ◽  
Starch Composition

Starch composition (amylose content) and the activities of starch-synthesizing enzymes were determined in cultures of Polytoma uvella and potatoes kept at various temperatures. In general ADPG-α-glucan glucosyltransferases were much less thermostable in vivo than P- and Q-enzymes. Potato phosphorylase proved to be the most stable enzyme. In Polytoma both P/Q ratio and amylose content decreased at 30 °C, whereas they remained unchanged in potatoes grown at 30 °C. This confirms the results from earlier experiments which indicated that the P/Q ratio is correlated with amylose content, and is also in agreement with the simultaneous increase in amylose percentage and P/Q ratio observed during the development of starch granules in corn endosperm. The results are discussed in relation to the problem of amylose production in starch granules and the importance of phosphorylase in starch synthesis.

scholarly journals Production of very-high-amylose cassava by post-transcriptional silencing of branching enzyme genes

2018 ◽  
Author(s):  
Wenzhi Zhou ◽  
Shanshan Zhao ◽  
Shutao He ◽  
Qiuxiang Ma ◽  
Xinlu Lu ◽  
...  
Keyword(s):  
Amylose Content ◽  
Length Distribution ◽  
Constitutive Expression ◽  
Raw Material ◽  
Distribution Analysis ◽  
Starch Granules ◽  
Storage Roots ◽  
Chain Length Distribution ◽  
Transgenic Cassava ◽  
High Amylose

AbstractHigh amylose starch, a desired raw material in the starch industry, can be produced by plants deficient in the function of branching enzymes (BEs). Here we report the production of transgenic cassava plants with starches containing up to 50% amylose due to the constitutive expression of hair-pin dsRNAs targeting the BE1 or BE2 genes. A significant decrease in BE transcripts was confirmed in these transgenic plants by quantitative real-time RT-PCR. The absence of BE1 protein in the BE1-RNAi plant lines (BE1i) and a dramatically lower level of BE2 protein in the BE2-RNAi plant lines (BE2i) were further confirmed by Western blot assays. All transgenic plant lines were grown up in the field, but with reduced biomass production of the above-ground parts and storage roots compared to wild type (WT). Considerably high amylose content in the storage roots of BE2i plant lines was achieved, though not in BE1i plant lines. Storage starch granules of BE1i and BE2i plants had similar morphology as WT, however, the size of BE1i starch granules were bigger than that of WT. Comparisons of amylograms and thermograms of all three sources of storage starches revealed dramatic changes to the pasting properties and a higher melting temperature for BE2i starches. Glucan chain length distribution analysis showed a slight increase in chains of DP>36 in BE1i lines and a dramatic increase in glucan chains between DP 10-20 and DP>40 in BE2i lines, compared to that of WT starch. Furthermore, BE2i starches displayed a B-type X-ray diffraction pattern instead of the A-type pattern found in BE1i and WT starches. Therefore, cassava BE1 and BE2 function differently in storage root starch biosynthesis; silencing of cassava BE1 or BE2 caused various changes to starch physico-chemical properties and amylopectin structure. We also report that remarkably high amylose content in cassava starch has been first obtained in transgenic cassava by silencing of BE2 expression, thus showing a high potential for future industrial utilization.

scholarly journals In Vitro and In Vivo Digestibility of Native Maize Starch Granules Varying in Amylose Contents

2007 ◽  
Vol 90 (6) ◽  
pp. 1628-1634 ◽  
Author(s):  
Tatsuya Morita ◽  
Yusuke Ito ◽  
Ian Lewis Brown ◽  
Ryuichi Ando ◽  
Shuhachi Kiriyama
Keyword(s):  
Surface Area ◽  
Linear Correlation ◽  
Resistant Starch ◽  
Amylose Content ◽  
Starch Granules ◽  
Gelatinization Temperature ◽  
Maize Starch ◽  
Positive Linear Correlation

Abstract Digestibility of maize starch granules with different amylose content (AL-0, 22, 54, 68, 80, or 90) was investigated. Measurement of the in vivo resistant starch (RS) content of the starches was performed using surgically prepared ileorectostomized rats. The rats were fed a purified diet containing one of the starches at 652.5 g/kg diet. The in vivo RS content was determined based on the fecal starch excretion. The dietary fiber (DF) value increased as a function of the amylose content in the starch and showed a positive linear correlation with the gelatinization temperature of the granules. In contrast, the in vitro RS content was likely to depend on both the surface area and amylose contents of the starch granules. The maximum in vitro RS content was obtained with AL-68 (54.4). In vivo RS content showed a significant correlation with the amount of in vitro RS but not in respect to the DF detected. The in vivo RS content of AL-68 (43.4) was higher than that found in AL-90 (37.8). A profound gap was observed for AL-54 between the amount of DF (6.4) and RS (in vitro = 46.6 and in vivo = 40.9) present. The results suggest that both in vitro and in vivo digestibility of maize starch is affected by the amylose content and surface area of the granules. The current evaluation suggests that the physiological occurrence of RS from maize starch might be predictable by reference to the in vitro RS value.

scholarly journals Protein content correlates with starch morphology, composition and physicochemical properties in field peas

2016 ◽  
Vol 96 (3) ◽  
pp. 404-412 ◽  
Author(s):  
Shian Shen ◽  
Hongwei Hou ◽  
Chunbang Ding ◽  
Deng-Jin Bing ◽  
Zhen-Xiang Lu
Keyword(s):  
Thermal Properties ◽  
Physicochemical Properties ◽  
Protein Content ◽  
Differential Scanning Calorimeter ◽  
Amylose Content ◽  
Enthalpy Change ◽  
High Protein ◽  
Starch Granules ◽  
Field Peas ◽  
Shape And Size

Protein and starch are two major components in field peas. In this study, we investigated the starch morphologies, compositions, and thermal properties between high protein peas (approximately 30%) and other market types of field peas (yellow, green, maple, and marrowfat peas, with approximately 23% protein contents). For the shape and size, high protein peas had the compound starch granules that could be easily fragmented into small irregular and polygonal granules, whereas other pea types had oval or kidney-like starch granules with high percentage of large granule sizes. High protein peas had significantly lower starch contents (27.2%–34.2%) than other pea types (45.5%–47.4%). However, the amylose content (74.6%–89.2%) in high protein peas were significantly higher that of other pea types (50.1%–54.1%). Our differential scanning calorimeter (DSC) data showed that the onset temperature (To), peak temperature (Tp), and conclusion temperature (Tc) of starch gelatinization in high protein peas were significantly higher than those of other pea types, whereas the enthalpy change (ΔH) of high protein peas was significantly lower than those of other pea types. The unique properties of high protein peas characterized in this study provided useful information to further improve pea quality.

Physicochemical and Functional Properties of Cultivars of Irish Potato and Cassava Starches

2009 ◽  
Vol 5 (3) ◽  
Author(s):  
Pierre Désiré Mbougueng ◽  
Tenin Dzudie ◽  
Joel Scher ◽  
Tchiégang Clergé
Keyword(s):  
Functional Properties ◽  
Phosphorus Content ◽  
Amylose Content ◽  
Potato Starch ◽  
Irish Potato ◽  
Starch Granules ◽  
Colour Difference ◽  
Physico Chemical ◽  
Granule Morphology ◽  
Potato Starches

In this study, starches were extracted from two cultivars of local Irish potatos (Solanum tuberosum,) and tree cultivars of local Cassava (Manihot esculanta). These starches and a commercial Irish potato starch (IPS), where characterized with respect to their physico-chemical and functional properties. Significant differences (P<0.05) were observed among starches as far as their proximate composition were concerned. The commercial starch showed the highest phosphorus content. The amylose content was observed to be significantly lower (P<0.05) in the cassava starches than in the local Irish potato starches. The highest (P<0.05) gelatinisation parameters were those of 2425 starch cultivar. Potato starch granules exhibited the largest granule size at 10, 50 and 90% diameter compared to those of cassava starches. Potato starches had wider particle size distribution compared to cassava starches. There were apparent differences, between species (Cassava and potatoes) with respect to granule morphology and size. No significant colour difference (P>0.05) was observed between the Sipiera starch cultivars and the Irish potatoes commercial starch.

scholarly journals Identification and molecular characterization of mutant line deficiency in three waxy proteins of common wheat (Triticum aestivum L.)

2019 ◽  
Author(s):  
Qian Liu ◽  
Yaping Hu ◽  
Mengyun Hu ◽  
Lijing Sun ◽  
Xiyong Chen ◽  
...  
Keyword(s):  
Triticum Aestivum ◽  
Amylose Content ◽  
Premature Stop Codon ◽  
Triticum Aestivum L ◽  
Starch Granules ◽  
Null Line ◽  
Wild Type ◽  
Expression Levels ◽  
Waxy Proteins ◽  
Total Starch

Abstract Background: Starch is the main component of wheat (Triticum aestivum L.) grain and a key factor in determining wheat processing quality. The Wx gene encodes the granule bound starch synthase I (GBSS I) and is the sole gene responsible for amylose synthesis. Results: A waxy mutant (Wx-null) was isolated by screening M3 seeds derived from 1.0% EMS mutagenized materials with I2-KI staining of endosperm starch. SDS-PAGE electrophoresis confirmed that the Wx-null line lacked all three waxy proteins. DNA sequencing revealed three SNPs and a 3-bp InDel in the first exon, and a 16-bp InDel at the junction region of the first Wx-A1 intron from the Wx-null line. Six SNPs were identified in Wx-B1 gene of Wx-null line compared to the wild-type Gao 8901, including four missense mutations. One nonsense mutation was found at position 857 in the fourth exon, which resulted in a premature stop codon. Expression levels of Wx genes were dramatically reduced in the Wx-null line. Nonsense-mediated mRNA decay (NMD) may be triggered to degrade the non-functional Wx mRNA. There were no detectable differences in granule size and morphology between Wx-null and wild-type, but the Wx-null line contained a larger proportion of B-type starch granules. The amylose content of the Wx-null line (0.22%) was remarkably lower compared to the wild-type Gao 8901 (20.82%). Total starch is also lower in the Wx-null line. Conclusions: All three waxy proteins were non-functional in the Wx-null line. NMD may be the cause for reduced expression levels of Wx genes in the Wx-null line. The Wx-null line exhibited more B-type starch granules, dramatically lower amylose content, and decreased total starch. The Wx-null line may provide a potential waxy material with high agronomic performance in wheat breeding programs.

scholarly journals Starch Granule Size Distribution and Pasting Characteristic Response to Post-Anthesis Combined Stress of Waterlogging and Shading

Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 384
Author(s):  
Huawei Li ◽  
Zongshuai Wang ◽  
Qicui Zhuo ◽  
Bin Zhang ◽  
Fahong Wang ◽  
...  
Keyword(s):  
Size Distribution ◽  
Amylose Content ◽  
Starch Content ◽  
Grain Filling ◽  
Triticum Aestivum L ◽  
Granule Size ◽  
Starch Granules ◽  
Combined Stress ◽  
Low Viscosity ◽  
Pasting Characteristics

The combined stress of waterlogging and shading (WS) caused by continuous rain threatens the production of high-quality weak gluten wheat in China (Triticum aestivum L.). To evaluate its influences on wheat quality formation, Yangmai 158 was chosen to be subjected to WS at 0–7 days after anthesis (DAA, WS0–7), 8–15 DAA (WS8–15), 16–23 DAA (WS16–23), and 24–31 DAA (WS24–31), respectively, with non-stressed plants as control (Non-WS). Compared with Non-WS, WS reduced the amylopectin content and enhanced amylose content in the mature grains. WS enhanced the number and surface but reduced the size of the starch granules. The number, volume, and surface area percentages of B-type starch granules were enhanced, and the number and volume percentages of A-type starch granules were reduced by WS. The peak viscosity and gelatinization temperature were enhanced and the low viscosity and final viscosity were decreased by WS. WS applied at the mid-grain-filling stage (WS8–15 and WS16–23) had greater modification on the starch content, granule size distribution and pasting characteristics than that applied at early (WS0–7) or late (WS24–31). The changes of starch pasting characteristics under WS had a significant correlation with the amylase and amylopectin content, amylase/amylopectin, and the ratio of the volume percent of B-type and A-type starch granules.

A mutation in Waxy gene affects amylose content, starch granules and kernel characteristics of barley ( Hordeum vulgare )

2019 ◽  
Vol 138 (5) ◽  
pp. 513-523 ◽  
Author(s):  
Qiao Li ◽  
Zhifen Pan ◽  
Juan Liu ◽  
Guangbing Deng ◽  
Hai Long ◽  
...  
Keyword(s):  
Hordeum Vulgare ◽  
Amylose Content ◽  
Waxy Gene ◽  
Starch Granules

scholarly journals Physical and chemical properties of starch and flour from different common bean (Phaseolus vulgaris L.) cultivars

2016 ◽  
Vol 19 (0) ◽  
Author(s):  
Milene Marquezi ◽  
Vanessa Maria Gervin ◽  
Lucas Bertoldi Watanabe ◽  
Priscila Zaczuk Bassinello ◽  
Edna Regina Amante
Keyword(s):  
Phaseolus Vulgaris ◽  
Amylose Content ◽  
Chemical Properties ◽  
Pasting Properties ◽  
Starch Granules ◽  
Phaseolus Vulgaris L ◽  
Absolute Density ◽  
Density Values ◽  
Physical And Chemical ◽  
And Chemical Properties

Summary The physical, chemical and pasting properties of the flour and isolated starches from six different bean cultivars (Phaseolus vulgaris L.) were investigated in order to obtain information for application in new products. The protein and total starch contents of the bean flours ranged from 17.72 to 20.27% and from 39.68 to 43.78%, respectively. The bean starches had low amounts of proteins, lipids and ash and showed an amylose content ranging between 45.32 and 51.11% and absolute density values between 1.55 and 1.78 g.cm–3. The bean starch granules were round to oval with a smooth surface. Results viscoamylographic profiles of the starches and flours showed the possibility of selecting cultivars for specific applications according to these characteristics.

Sign in / Sign up

Export Citation Format

Share Document