scholarly journals Exaggerated expectations in ancient starch research and the need for new taphonomic and authenticity criteria

2018 ◽  
Author(s):  
Julio Mercader ◽  
Mariam Bundala ◽  
Matthew J. Collins ◽  
Les Copeland ◽  
Alison Crowther ◽  
...  
Keyword(s):  
Human Ecology ◽  
Starch Granule ◽  
Economic Systems ◽  
Starch Granules ◽  
Cultural Complexity ◽  
Geochemical Characterization ◽  
Degradable Polymer ◽  
Changing Environments ◽  
Future Work ◽  
New Criteria

Ancient starch research illuminates aspects of human ecology and economic botany that drove human evolution and cultural complexity over time, with a special emphasis on past technology, diet, health, and adaptation to changing environments and socio-economic systems. However, lapses in prevailing starch research demonstrate the exaggerated expectations for the field that have been generated over the last few decades, including an absence of explanation for the millennial survivability of a biochemically degradable polymer, and difficulties in proving authenticity and taxonomic identification. These flaws perpetuate skepticism and place credibility at risk. By applying new criteria and using a model that puts greater emphasis on detailed authentication procedures, including bio-geochemical characterization, starch granule preservation pathways will be clarified. Future work must consider growing demands from readers, editors, and reviewers that look for objective compositional identification of putatively ancient starch granules.

scholarly journals Exaggerated expectations in ancient starch research and the need for new taphonomic and authenticity criteria

FACETS ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 777-798 ◽  
Author(s):  
Julio Mercader ◽  
Tolutope Akeju ◽  
Melisa Brown ◽  
Mariam Bundala ◽  
Matthew J. Collins ◽  
...  
Keyword(s):  
Economic Botany ◽  
Human Ecology ◽  
Economic Systems ◽  
Taxonomic Identification ◽  
Starch Granules ◽  
Cultural Complexity ◽  
Degradable Polymer ◽  
Changing Environments ◽  
Future Work ◽  
Over Time

Ancient starch research illuminates aspects of human ecology and economic botany that drove human evolution and cultural complexity over time, with a special emphasis on past technology, diet, health, and adaptation to changing environments and socio-economic systems. However, lapses in prevailing starch research demonstrate the exaggerated expectations for the field that have been generated over the last few decades. This includes an absence of explanation for the millennial-scale survivability of a biochemically degradable polymer, and difficulties in establishing authenticity and taxonomic identification. This paper outlines new taphonomic and authenticity criteria to guide future work toward designing research programs that fully exploit the potential of ancient starch while considering growing demands from readers, editors, and reviewers that look for objective compositional identification of putatively ancient starch granules.

Production and Characterization of Porous Starch Granule and Poly(butylene adipate-co-terephthalate) Blend as a Bio-Composite

2012 ◽  
Vol 550-553 ◽  
pp. 1513-1521
Author(s):  
Sirirat Thothong ◽  
Klanarong Sriroth ◽  
Rattana Tantatherdtam ◽  
Amnat Jarerat
Keyword(s):  
Starch Granule ◽  
Rice Starch ◽  
Starch Granules ◽  
Screw Extruder ◽  
Elongation At Break ◽  
Single Screw ◽  
Single Screw Extruder ◽  
Scanning Electron ◽  
Granular Starch

To improve the miscibility of native rice starch granules and poly(butylene adipate-co-terephthalate)(PBAT), rice starch was hydrolyzed by a mixture of α-amylase and amyloglucosidase. The obtained porous rice granular starch was then mechanically blended with PBAT by single screw extruder. Many pits and holes on the surface of starch granules were observed by scanning electron microscopy (SEM). The rough surface of the rice starch granules improved the compatibility of the polymers in the blends, which consequently increased the tensile strength and the elongation at break. In addition, SEM also revealed that the porous granules were homogeneously distributed in the polymer matrix with no appearance of gaps.

scholarly journals Starch Granule Size and Morphology of Arabidopsis thaliana Starch-Related Mutants Analyzed during Diurnal Rhythm and Development

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5859
Author(s):  
Qingting Liu ◽  
Yuan Zhou ◽  
Joerg Fettke
Keyword(s):  
Arabidopsis Thaliana ◽  
Starch Granule ◽  
Granule Size ◽  
High Temporal Resolution ◽  
Starch Granules ◽  
Transitory Starch ◽  
Young Leaves ◽  
Size And Morphology ◽  
Safranin O

Transitory starch plays a central role in the life cycle of plants. Many aspects of this important metabolism remain unknown; however, starch granules provide insight into this persistent metabolic process. Therefore, monitoring alterations in starch granules with high temporal resolution provides one significant avenue to improve understanding. Here, a previously established method that combines LCSM and safranin-O staining for in vivo imaging of transitory starch granules in leaves of Arabidopsis thaliana was employed to demonstrate, for the first time, the alterations in starch granule size and morphology that occur both throughout the day and during leaf aging. Several starch-related mutants were included, which revealed differences among the generated granules. In ptst2 and sex1-8, the starch granules in old leaves were much larger than those in young leaves; however, the typical flattened discoid morphology was maintained. In ss4 and dpe2/phs1/ss4, the morphology of starch granules in young leaves was altered, with a more rounded shape observed. With leaf development, the starch granules became spherical exclusively in dpe2/phs1/ss4. Thus, the presented data provide new insights to contribute to the understanding of starch granule morphogenesis.

scholarly journals A carbohydrate-binding protein, B-GRANULE CONTENT 1, influences starch granule size distribution in a dose-dependent manner in polyploid wheat

2019 ◽  
Vol 71 (1) ◽  
pp. 105-115 ◽  
Author(s):  
Tansy Chia ◽  
Marcella Chirico ◽  
Rob King ◽  
Ricardo Ramirez-Gonzalez ◽  
Benedetta Saccomanno ◽  
...  
Keyword(s):  
Size Distribution ◽  
Starch Granule ◽  
Starch Synthesis ◽  
Granule Size ◽  
Starch Granules ◽  
Grain Development ◽  
Polyploid Wheat ◽  
Gene Dose ◽  
Dose Dependent ◽  
B Granules

Abstract In Triticeae endosperm (e.g. wheat and barley), starch granules have a bimodal size distribution (with A- and B-type granules) whereas in other grasses the endosperm contains starch granules with a unimodal size distribution. Here, we identify the gene, BGC1 (B-GRANULE CONTENT 1), responsible for B-type starch granule content in Aegilops and wheat. Orthologues of this gene are known to influence starch synthesis in diploids such as rice, Arabidopsis, and barley. However, using polyploid Triticeae species, we uncovered a more complex biological role for BGC1 in starch granule initiation: BGC1 represses the initiation of A-granules in early grain development but promotes the initiation of B-granules in mid grain development. We provide evidence that the influence of BGC1 on starch synthesis is dose dependent and show that three very different starch phenotypes are conditioned by the gene dose of BGC1 in polyploid wheat: normal bimodal starch granule morphology; A-granules with few or no B-granules; or polymorphous starch with few normal A- or B-granules. We conclude from this work that BGC1 participates in controlling B-type starch granule initiation in Triticeae endosperm and that its precise effect on granule size and number varies with gene dose and stage of development.

Controlled Release Starch Granule Formulations Reduce Herbicide Leaching in Soil Columns

1992 ◽  
Vol 6 (2) ◽  
pp. 317-321 ◽  
Author(s):  
Rick A. Boydston
Keyword(s):  
Controlled Release ◽  
Starch Granule ◽  
Soil Column ◽  
Loamy Sand ◽  
Starch Granules ◽  
Soil Columns ◽  
Sand Soil ◽  
Water Dispersible ◽  
Loamy Sand Soil ◽  
Water Dispersible Granule

Experimental controlled release starch granules (CRSG) containing 5.3% a.i. (w/w) norflurazon or 6% a.i. (w/w) simazine retarded the leaching of both herbicides in loamy sand soil columns when compared to commercial formulations of norflurazon [80% (w/w) dry flowable] or simazine [90% (w/w) water dispersible granule]. Barley bioassays indicated norflurazon and simazine remained in the surface 0 to 2.5 cm of soil when applied as CRSG formulations and moved to a depth of 15 cm when applied as commercial dry formulations and leached with 6 cm of water. CRSG placed on pre-wetted soil columns began to release norflurazon by 7 d at 25 C or 14 d at 15 C, and subsequent leaching moved norflurazon beyond the top 2.5 cm of the soil column.

Physiology of Cereal Grain II. Starch Granule Formation in the Developing Barley Kernel

1959 ◽  
Vol 12 (2) ◽  
pp. 146 ◽  
Author(s):  
LH May ◽  
MS Buttrose
Keyword(s):  
Starch Granule ◽  
Dry Weight ◽  
Type A ◽  
Starch Granules ◽  
Type B ◽  
Granule Formation ◽  
Rate Of Increase ◽  
Cereal Grain ◽  
Barley Kernel ◽  
B Granules

Types, numbers, volumes, and weights of starch granules in the barley endosperm were measured at different times from anthesis to maturity. The formation of two types of granule was confirmed: the first (type A) was initiated until 15 days after anthesis; the second (type B) between 18 and 30 days. At maturity there were approximately 10 times as many type B granules as type A, although the latter made up 90 per cent. of the total granule volume. There was a linear relationship between starch granule and endosperm volume throughout kernel development, while the rate of increase in volume per unit granule volume was the same, irrespective of granule size, at anyone time. Starch weight increased as endosperm dry weight increased although the precise form of this relationship is in doubt. The interrelationships between starch granule weight and volume, and also endosperm dry weight and volume, suggest that both starch granules and endosperm increase in density during development.

scholarly journals Variance of Zein Protein and Starch Granule Morphology between Corn and Steam Flaked Products Determined Starch Ruminal Degradability Through Altering Starch Hydrolyzing Bacteria Attachment

Animals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 626 ◽  
Author(s):  
NingNing Xu ◽  
DiMing Wang ◽  
JianXin Liu
Keyword(s):  
Starch Granule ◽  
Starch Granules ◽  
Protein Patterns ◽  
Dapi Staining ◽  
Sds Page ◽  
Gelatinized Starch ◽  
Ruminal Degradation ◽  
Granule Morphology ◽  
Median Particle ◽  
Zein Protein

The current study investigated differences of γ-zein protein contents and starch granule characteristics between raw and steam flaked corns and their influences on ruminal starch hydrolyzing bacteria (SHB) attached to corn grain. Two types of raw (Corn1 and Corn2) and their steam-flaked products (SFCorn1 and SFCorn2) were applied to explore physiochemical structures and SHB attachment. SDS-PAGE was conducted to detect γ-zein protein patterns, scanning electron microscope, and small angle X-ray scattering were performed to obtain starch granule morphology, while crystallinity, DQ starch, and DAPI staining were applied to quantify SHB. The steam flaking process destroyed γ-zein proteins and gelatinized starch granules. The median particle size of Corn1 and Corn2 starch granules increased from 17.8 and 18.0 μm to 30.8 and 26.0 μm, but crystallinity decreased from 22.0 and 25.0% to 9.9 and 16.9%, respectively. The percentage of SHB attached to Corn1 residues decreased (p = 0.01) after 4 h incubation, but SHB attached to SFCorn1 residues increased (p = 0.03) after 12 h incubation. Thus, the differences of γ-zein proteins and starch granule physiochemical structures between raw and steam flaked corn played an important role in improving the rate and extent of starch ruminal degradation through altering the process of SHB attached to corn.

scholarly journals Mass Spectrometric Analysis Reveals Remnants of Host–Pathogen Molecular Interactions at the Starch Granule Surface in Wheat Endosperm

2010 ◽  
Vol 100 (9) ◽  
pp. 848-854 ◽  
Author(s):  
Michael L. Wall ◽  
Heather L. Wheeler ◽  
Jeffrey Smith ◽  
Daniel Figeys ◽  
Illimar Altosaar
Keyword(s):  
Molecular Interactions ◽  
Plant Pathogens ◽  
Magnaporthe Grisea ◽  
Starch Granule ◽  
Surface Proteins ◽  
Molecular Evidence ◽  
Starch Granules ◽  
Wheat Seed ◽  
Host Pathogen ◽  
Granule Surface

The starch granules of wheat seed are solar energy-driven deposits of fixed carbon and, as such, present themselves as targets of pathogen attack. The seed's array of antimicrobial proteins, peptides, and small molecules comprises a molecular defense against penetrating pathogens. In turn, pathogens exhibit an arsenal of enzymes to facilitate the degradation of the host's endosperm. In this context, the starch granule surface is a relatively unexplored domain in which unique molecular barriers may be deployed to defend against and inhibit the late stages of infection. Therefore, it was compelling to explore the starch granule surface in mature wheat seed, which revealed evidence of host–pathogen molecular interactions that may have occurred during grain development. In this study, starch granules from the soft wheat Triticum aestivum cv. AC Andrew and hard wheat T. turgidum durum were isolated and water washed 20 times, and their surface proteins were digested in situ with trypsin. The peptides liberated into the supernatant and the peptides remaining at the starch granule surface were separately examined. In this way, we demonstrated that the identified proteins have a strong affinity for the starch granule surface. Proteins with known antimicrobial activity were identified, as well as several proteins from the plant pathogens Agrobacterium tumefaciens, Pectobacterium carotovorum, Fusarium graminearum, Magnaporthe grisea, Xanthomonas axonopodis, and X. oryzae. Although most of these peptides corresponded to uncharacterized hypothetical proteins of fungal pathogens, several peptide fragments were identical to cytosolic and membrane proteins of specific microbial pathogens. During development and maturation, wheat seed appeared to have resisted infection and lysed the pathogens where, upon desiccation, the molecular evidence remained fixed at the starch granule surface.

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