Kernel Starch Research Articles

Impact of soil moisture stress during the silk emergence and grain-filling in maize.

Suboptimal soil moisture during the growing season often limits maize growth and yield. However, the growth stage-specific responses of maize to soil moisture regimes have not been thoroughly investigated. This study investigated the response of maize to five different soil moisture regimes, that are, 0.25, 0.20, 0.15, 0.10, and 0.05 m3 m-3 volumetric water content (VWC), during flowering and grain-filling stages. Sub-optimal soil moisture at the flowering and grain-filling stages reduced ear leaf stomatal conductance by 73 and 64%, respectively. An increase in stress severity caused significant reductions in ear leaf chlorophyll content and greenness-associated vegetation indices across growth stages. Fourteen days of soil moisture stress during flowering delayed silk emergence, reduced silk length (19%), and silk fresh weight (34%). Furthermore, sub-optimal soil moisture caused a significant reduction in both kernel number (53%) and weight (54%). Soil moisture stress at the flowering had a direct impact on kernel number and an indirect effect on kernel weight. During grain-filling, disruption of ear leaf physiology resulted in a 34% decrease in kernel weight and a 43% decrease in kernel number. Unlike grain-filling, treatments at the flowering significantly reduced kernel starch (3%) and increased protein by 29%. These findings suggest that developing reproductive stage stress-tolerant hybrids with improved resilience to soil moisture stress could help reduce the yield gap between irrigated and rainfed maize.

Effects of acetylation, acid-thinning and oxidation on Chrysophyllum albidum (African star apple) kernel native starch

Starch is a biological macromolecule with myriad of industrial uses. The growing need for starch and native starch deficiencies have necessitated researches into under-exploited starch sources and modifications, respectively. Chrysophyllum albidum (African star apple, ASA) seed is a waste consisting of 63.94% carbohydrate in its kernel. Its starch content can be fully utilised, industrially, if it is in a suitable form and its properties understood. That necessitated the isolation of ASA kernel starch, its modification and properties assessment. Acetylation, acid-thinning and oxidation were performed on the native Chrysophyllum albidum kernel starch, NACA, to produce the acetylated Chrysophyllum albidum kernel starch, ACCA, acid-thinned Chrysophyllum albidum kernel starch, ATCA, and oxidised Chrysophyllum albidum kernel starch, OXCA, respectively. The physicochemical properties of the native and modified starches were investigated with established methods. The yield of starch was 43.76%. The acetylated and oxidised starches had low degrees of substitution. FTIR results confirmed the introduction of carbonyl functionality into the acetylated and oxidised starches. Starch morphology revealed smooth, small rounded and truncated ellipsoid granules with diameter ranges of 7–20 μm. Swelling power of modified starches improved, except for the acid-thinned, and increased with temperature. Acetylated and oxidised starches had significantly (p < 0.05) higher water and oil absorption capacities, respectively. Acid-thinning significantly improved starch pasting properties and reduced retrogradation tendency. Modification improved the gelatinisation transition temperature of native starch.

Effects of CeO2 Nanoparticles on Nutritional Quality of Two Crop Plants, Corn (Zea mays L.) and Soybean (Glycine max L.)

With the widespread applications of manufactured nanoparticles (NPs), there are increasing concerns about their potential adverse effects on the environment and living systems. Many studies demonstrated that NPs could significantly affect the growth and development of crop plants. However, knowledge regarding the impacts of NPs on crop quality is rather limited. In this study, the effects of CeO2 NPs (25, 75, and 225 mg Ce/kg) and CeCl3 (25 mg Ce/kg) on the nutritional components of soil-cultivated corn and soybean plants were evaluated. Both treatments tended to decrease the dry weight of grain per plant, while only 225 mg/kg CeO2 NPs on soybean and CeCl3 on corn showed statistical significance compared with the respective control. CeO2 NPs at 225 mg/kg significantly decreased the content of starch in the corn kernels by 18.2% but increased total phenols in soybean seeds by 18.4%. Neither CeO2 NPs nor CeCl3 significantly affected the contents of minerals in corn kernels except for Zn. However, in the case of soybean, the two treatments tended to decrease the contents of P, Zn, Mn, and Mo but increase the content of S. Overall, the results suggest that CeO2 NPs and Ce3+ ions showed similar but not identical effects on corn and soybean plants. CeO2 NPs affect the nutritional quality of crop plants in a species-dependent manner.

Ultrasound-Assisted Extraction of Mango (Mangifera indica) Kernel Starch: Chemical, Techno-Functional, and Pasting Properties

(1) Background: Starch is the main component of mango (Mangifera indica) kernel, making it an alternative to obtain an ingredient from a non-conventional source with potential application in food and other industrial applications; however, reports on the use of new extraction techniques for this material are scarce. The main objective of this research was to evaluate the effect of ultrasound-assisted extraction (UAE) on the yield, chemical, techno-functional, rheological, and pasting properties of starch isolated from a non-conventional source such as a mango kernel. (2) Methods: Different power sonication conditions (120, 300, and 480 W) and sonication time (10, 20, and 30 min) were evaluated along with a control treatment (extracted by the wet milling method). (3) Results: Ultrasound-assisted extraction increases starch yield, with the highest values (54%) at 480 W and 20 min. A significant increase in the amylose content, water-holding capacity, oil-holding capacity, solubility, and swelling power of ultrasonically extracted starches was observed. Similarly, mango kernel starch (MKS) exhibited interesting antioxidant properties. The sol-gel transition temperature and pasting parameters, such as the breakdown viscosity (BD) and the setback viscosity (SB), decreased with ultrasound application; (4) Conclusion: indicating that ultrasound caused changes in physical, chemical, techno-functional, rheological, and pasting properties, depending on the power and time of sonication, so it can be used as an alternative starch extraction and modification technique, for example, for potential application in thermally processed food products such as baked goods, canned foods, and frozen foods.

Cultivars and Fruit Part as Differentiating Factors of Physicochemical Characteristics of Mango Starches

Fruit production has increased, which has led to an increase in fruit wastage, opening up new opportunities for the use of non-standard fruits as starch sources. Herein, the physicochemical properties of mango starches isolated from the pulp and kernel of four cultivars were investigated. The pulp starches showed higher purity with total starch ranging from 97.84 to 98.09% (dry basis). The kernel starches had a higher percentage of other components (ash, fiber, lipids, protein, sugars). The main mineral in the starches was potassium (0.37 to 1.32 g/kg). Pulp starches were circular and smaller (15–79 to 16.70 µm) and kernel starches were oval and larger (19.75 to 25.33 µm). Differential scanning calorimetry and rapid viscosity studies showed that the kernel starches had higher gelatinization properties. The mango starches were A-type with varying crystallinity levels (28.37–32.35%). PCA analysis showed the greater impact of gelatinization properties on the grouping of cultivars. These findings would be useful for adding commercial value to mango agricultural and industrial waste and for industries in terms of using the starch as an ingredient in food products and other industrial applications.

Association Mapping of Amylose Content in Maize RIL Population Using SSR and SNP Markers.

The ratio of amylose to amylopectin in maize kernel starch is important for the appearance, structure, and quality of food products and processing. This study aimed to identify quantitative trait loci (QTLs) controlling amylose content in maize through association mapping with simple sequence repeat (SSR) and single-nucleotide polymorphism (SNP) markers. The average value of amylose content for an 80-recombinant-inbred-line (RIL) population was 8.8 ± 0.7%, ranging from 2.1 to 15.9%. We used two different analyses-Q + K and PCA + K mixed linear models (MLMs)-and found 38 (35 SNP and 3 SSR) and 32 (29 SNP and 3 SSR) marker-trait associations (MTAs) associated with amylose content. A total of 34 (31 SNP and 3 SSR) and 28 (25 SNP and 3 SSR) MTAs were confirmed in the Q + K and PCA + K MLMs, respectively. This study detected some candidate genes for amylose content, such as GRMZM2G118690-encoding BBR/BPC transcription factor, which is used for the control of seed development and is associated with the amylose content of rice. GRMZM5G830776-encoding SNARE-interacting protein (KEULE) and the uncharacterized marker PUT-163a-18172151-1376 were significant with higher R2 value in two difference methods. GRMZM2G092296 were also significantly associated with amylose content in this study. This study focused on amylose content using a RIL population derived from dent and waxy inbred lines using molecular markers. Future studies would be of benefit for investigating the physical linkage between starch synthesis genes using SNP and SSR markers, which would help to build a more detailed genetic map and provide new insights into gene regulation of agriculturally important traits.

Ex-ante life cycle assessment framework and application to a nano-reinforced biopolymer film based on mango kernel

This article proposes a framework for ex-ante life cycle assessment (LCA) of biopolymers at low TRL, including: (i) scale-up; (ii) scenarios for processes and modelling choices; (iii) comparison with a fossil-based polymer, considering material substitution factors. The framework was applied to analyse a mango kernel starch (MKS) film and compare it with low-density polyethylene (LDPE). Mango seeds (feedstock) were modelled as burden-free since they do not have economic value (baseline). An industrial-scale model was built for the production of starch nanocrystals (SNC) and MKS film using process calculations based on experimental data. Most impacts occur at starch and SNC extraction due to steam and acid consumption. Compared to LDPE, MKS performs better in non-renewable energy use but worse in climate change, freshwater eutrophication, and terrestrial acidification. Scenario analysis showed that yield enhancement and acid shifting could considerably reduce impacts. The proposed framework shows potential to support sustainable innovation of biopolymers.

Characterization of the physicochemical, thermal and rheological properties of cashew kernel starch.

The study aimed to characterize physicochemical, thermal, and rheological properties of cashew nut starch (CNS) and then compare the obtained results with the properties of potato and corn starches. CNS showed higher gelatinization temperatures (112.29°C) than those noted for potato and maize starches (78.44-94.65°C). In addition, CNS had higher peak viscosity (19.03mPa·s) than high amylose corn starch. The static shear rheological test indicated that the CNS followed a pseudoplastic behavior. In addition, CNS sample showed a thixotropic patter, which was less pronounced than that observed for potato starch, but higher than the value reported for high amylose corn starch. These results demonstrated that the shear resistance of CNS was lower than high amylose corn starch, but higher than potato starch. The storage and loss modulus (G' and G", respectively) of the CNS were higher than those reported for the rest of samples. In this line, elastic properties were predominant in CNS sample. In conclusion, results from this study provided insight into physicochemical and structural properties of cashew nut starch, which could represent a preliminary step for its future application in food processing.

The 218th amino acid change of Ser to Ala in TaAGPS-7A increases enzyme activity and grain weight in bread wheat

ADP-glucose pyrophosphorylase (AGPase) influences cereal productivity. There are few reports on the function of cytosolic AGPase small subunit in bread wheat (TaAGPS). In the present study, TaAGPS was preferentially expressed in developing endosperm during grain-filling stages in bread wheat. TaAGPS allelic variations were characterized in 143 wheat accessions by PacBio RS II sequencing. Two haplotypes (TaAGPS-7A-TG and TaAGPS-7A-CT) of TaAGPS-7A were identified and corresponding functional markers were developed, whereas no variants of TaAGPS-7B and TaAGPS-7D were detected. TaAGPS-7A was associated with thousand-kernel weight (TKW) by haplotype–trait association analysis in two populations. Near-isogenic lines (NILs) with TaAGPS-7A-TG showed higher TKW and total kernel starch content than those with TaAGPS-7A-CT, owing to the higher AGPase activity of TaAGPS-7A-TG than TaAGPS-7A-CT both in vitro and in vivo. Overexpression of TaAGPS-7A-TG in bread wheat doubled the transcription levels of TaAGPS and increased AGPase activity by 55.7%, resulting in a 3.0-g higher TKW than in the wild type (WT). Knockdown of TaAGPS led to reduced expression of TaAGPS, AGPase activity, and TKW than in the WT. Thus, owing to the 218th amino acid change of Ser to Ala in TaAGPS-7A, the favorable haplotype TaAGPS-7A-TG showed higher AGPase activity, resulting in higher kernel starch content and grain weight. This finding could be applied to increasing starch content and grain weight in bread wheat.

Bioconversion of mango (Mangifera indica) seed kernel starch into bioethanol using various fermentation techniques

The potential of mango seed kernel starch (MKS) as a feedstock for bioethanol production was evaluated in this study. Starch extraction and hydrolysis from mango kernel were studied. Fermentation methods included separate hydrolysis and fermentation (SH&F), simultaneous saccharification and co-fermentation (SS&CF), simultaneous saccharification and fermentation (SS&F), and modified simultaneous saccharification and fermentation (SS&F) techniques. Drying and wet-milling generated 41.2 g of white starch/100 g flour, and processing with alum gave 58.6/100 g MKS. Hydrolysis of 5 g MKS by sulfuric acid, sodium hydroxide, malted “acha”, and Aspergillus niger amylase for 2 h produced (g/100 mL) 3.97 g, 4.0 g, 4.43 g and 4.24 g of sugar, respectively. Fermentation with 7 g of MKS yielded maximum sugar and ethanol concentrations. Ethanol obtained using SS&CF, SH&F, SS&F and modified SS&F were (v/v); 0.26%, 2.0%, 1.13% and 3.985%, respectively. These results confirmed MKS as a potential feedstock for bioethanol production.

Biodegradable Film from Mango Seed Kernel Starch Using Pottery Clay as Filler

Biodegradable Film from Mango Seed Kernel Starch Using Pottery Clay as Filler

Effects of Endogenous Polyphenols in Acorn (Quercus wutaishanica Blume) Kernels on the Physicochemical Properties of Starch

AbstractThe effects of endogenous polyphenols in acorn kernels on granule morphology, crystal properties, and in vitro digestibility of starch are investigated. The granule surface smoothness, relative crystallinity, short‐range molecular order, and starch hydrolysis rate increase after the removal of polyphenols from acorn flour. With the addition of polyphenol extracts, the hydrolysis rates of acorn, corn, potato, and chestnut starches are all reduced, and the free‐polyphenol extract shows higher inhibitory activity than the bound‐polyphenol extract. These results are expected to be helpful for understanding the low digestibility of starch in acorn kernels, which is attributed to the inhibitory effects of polyphenols on the activities of α‐amylase and α‐glucosidase, but not the increase of long and short‐range molecular orders of starch.

Development and Characterization of Edible Film Made from Mango Kernel Starch

Development and Characterization of Edible Film Made from Mango Kernel Starch

Development of Starch Nanoparticle from Mango Kernel in Comparison with Cereal, Tuber, and Legume Starch Nanoparticles: Characterization and Cytotoxicity

AbstractStarch nanoparticles (SNPs) are developed from mango kernel starch and are compared with wheat, potato, mungbean, and water chestnut starch nanoparticles. The synthesized SNPs are investigated for their thermal properties, particle size, degree of relative crystallinity and cytotoxicity. The average particle size of SNPs from different botanical sources range from 100 to 514 nm. Mango kernel starch nanoparticles show the highest particle size. Starch nanoparticles from all botanical sources show X‐ray diffraction (XRD) patterns similar to their native counterpart starches. SNPs from wheat, mango kernel, and water chestnut show A‐type XRD patterns but the relative crystallinity of SNPs is observed to be higher as compared to native starches. From the thermogravimetric analysis, it is observed that degradation temperature for 10% loss weight vary significantly. The study reveals that mango kernel SNPs show good biocompatibility with human HeLa cell lines as compared to all other sources except water chestnut SNPs.

Development and evaluation of novel nanofibers based on mango kernel starch obtained by electrospinning

This work reports on the development of fibers based on natural mango kernel starch (MKS) with diameters in the nanoscalse by means of the electrospinning technique. MKS was extracted from mango kernels and two synthetic polymers, namely polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), were blended with MKS in order to improve its spinnability, obtaining MKS/PVA and MKS/PVP fibers with a 10 wt% of total polymer concentration. Several electrospinning conditions (voltage and flux) were tested in solutions of MKS concentrations ranging from 0 to 5 wt% for both group of fibers. The morphology of all the fibers was evaluated by field emission scanning electron microscopy (FESEM) and their topography was analysed by means of atomic force microscopy (AFM). MKS/PVA nanofibers were obtained with a diameter range from 0.146 to 0.315 μm, with a “smooth fiber concentration threshold” of 3 wt%, while MKS/PVP, fibers with diameters from 0.080 to 0.339 μm were produced, but 5 wt% MKS concentration fibers were beaded fibers, as a result of an excess in starch concentration. Finally, the roughness of the optimal fibers showed quite a similar trend to that of fiber diameter, presenting roughnessess between 80 and 343 nm.

Physicochemical properties and structure of starches of foxnut ( Euryale ferox Salisb.) from India and its application

The physicochemical characteristics in terms of composition, pasting properties, in vitro starch digestibility, morphology, XRD, FT-IR, and functional properties of starch, isolated from the kernels of Euryale ferox seed cultivated in Northeastern Region of India were studied and utilized them in formulation of bread. E. ferox kernel starch (EFKS) exhibited an A-type diffraction pattern and granule sizes ranged from 1 to 3 μm in diameter and were polyhedral shape. EFKS exhibited high pasting temperature indicating its potential to incorporate in products requiring higher temperature to cook, such as baked items like bread. The effects of replacing refined wheat flour with native EFKS (5%–50% db) on bread quality attributes were investigated, and sensory results suggested that bread with 20% EFKS incorporation was acceptable, but bread with higher concentrations of EFKS produced smaller loaf volumes. Results evidenced that EFKS is a novel starch source and has an immense potential in both food and non-food industries. Novelty impact statement Results of the study have the credential evidence to corroborate that the Euryale ferox kernel starch (EFKS) has strong potential applications in food industries. The study also clearly revealed that EFKS can replace up to 20% of wheat flour for bread making with acceptable sensory attributes. The EFKS is comparable to popularly acceptable commercial starch-like rice and has potential for enormous food and non-food applications and can be a money spinner for entrepreneurs.

Effect of atmospheric pressure non-thermal pin to plate plasma on the functional, rheological, thermal, and morphological properties of mango seed kernel starch

This study aimed to investigate the effect of atmospheric pressure non-thermal pin-to-plate plasma on the functional, rheological, thermal, and morphological properties of mango seed kernel starch. As cold plasma contains highly reactive species and free radicals, it is expected to cause noticeable modifications in the attributes of starch treated. The isolated mango seed kernel starch was subjected to the plasma treatment of input voltages 170 and 230 V for 15 and 30 min of exposure. Water adsorption, swelling, and solubility at lower temperatures. There has been a significant reduction (p < 0.05) in pH values of starch from 7.09 to 6.16 and also the desirable reduction in turbidity values by 42.60%. However, there has been no significant change in the oil and water binding behavior of the starch. The FTIR spectra of MSKS demonstrate the formation of amines which contributes to the better hydrophilic nature of the starch. The structural modification has been adequately confirmed by SEM images. The maximum voltage and time combination, lead to depolymerization of starch which is supported by NMR spectra thus affecting thermal and rheological properties. The application of cold plasma-modified MSKS in food would facilitate stable and smooth textural development.

Proteomics reveals the effects of drought stress on the kernel development and starch formation of waxy maize

BackgroundKernel development and starch formation are the primary determinants of maize yield and quality, which are considerably influenced by drought stress. To clarify the response of maize kernel to drought stress, we established well-watered (WW) and water-stressed (WS) conditions at 1–30 days after pollination (dap) on waxy maize (Zea mays L. sinensis Kulesh).ResultsKernel development, starch accumulation, and activities of starch biosynthetic enzymes were significantly reduced by drought stress. The morphology of starch granules changed, whereas the grain filling rate was accelerated. A comparative proteomics approach was applied to analyze the proteome change in kernels under two treatments at 10 dap and 25 dap. Under the WS conditions, 487 and 465 differentially accumulated proteins (DAPs) were identified at 10 dap and 25 dap, respectively. Drought induced the downregulation of proteins involved in the oxidation–reduction process and oxidoreductase, peroxidase, catalase, glutamine synthetase, abscisic acid stress ripening 1, and lipoxygenase, which might be an important reason for the effect of drought stress on kernel development. Notably, several proteins involved in waxy maize endosperm and starch biosynthesis were upregulated at early-kernel stage under WS conditions, which might have accelerated endosperm development and starch synthesis. Additionally, 17 and 11 common DAPs were sustained in the upregulated and downregulated DAP groups, respectively, at 10 dap and 25 dap. Among these 28 proteins, four maize homologs (i.e., A0A1D6H543, B4FTP0, B6SLJ0, and A0A1D6H5J5) were considered as candidate proteins that affected kernel development and drought stress response by comparing with the rice genome.ConclusionsThe proteomic changes caused by drought were highly correlated with kernel development and starch accumulation, which were closely related to the final yield and quality of waxy maize. Our results provided a foundation for the enhanced understanding of kernel development and starch formation in response to drought stress in waxy maize.

Rheological and Microstructural Properties of Oil-in-Water Emulsion Gels Containing Natural Plant Extracts Stabilized with Carboxymethyl Cellulose/Mango (Mangiferaindica) Starch

Emulsion gels are an alternative to developing food products and adding bioactive compounds; however, different stabilizers have been employed considering natural ingredients. In this work, stabilization of emulsion gels with blends of carboxymethylcellulose and kernel mango starch was performed with the addition of mango peel extracts, evaluating their physical, rheological and microstructural properties. Phenolic extract from mango peels (yields = 11.35 ± 2.05% w/w), with 294.60 ± 0.03 mg GAE/100 g of extract and 436.77 ± 5.30 µMol Trolox/g of the extract, was obtained by ultrasound-assisted extraction (1:10 peel: Ethanol w/v, 200 W, 30 min), containing pyrogallol, melezitose, succinic acid, γ-tocopherol, campesterol, stigmasterol, lupeol, vitamin A and vitamin E. In addition, mango kernel starch (yields = 59.51 ± 1.35% w/w) with 27.28 ± 0.05% of amylose was obtained, being the by-product of mango (Mangiferaindica var fachir) an alternative to producing natural food ingredients. After that, stable emulsions gels were prepared to stabilize with carboxy methylcellulose–kernel mango starch blends and mango peel extracts. These results provide an ingredient as an alternative to the development of gelled systems. They offer an alternative to elaborating a new multifunctional food system with bioactive properties with potential application as a fat replacement or delivery system in the food industry.

Biosynthesis, structure and functionality of starch granules in maize inbred lines with different kernel dehydration rate

In this study, we report important relationships between kernel starch and kernel dehydration rate for eight maize inbred lines with different dehydration characteristics. High-throughput RNA sequencing data of starch biosynthesis-related genes showed that kernel moisture content and dehydration rate were both associated with differential expression of most starch biosynthetic genes. Especially, kernel moisture content was positively correlated with the increased expression of SBEI and SBEIIb, thereby potentially inducing biosynthesis of amylose with low molecular weight and amylopectin with low content of amylopectin chains with degree of polymerization (DP) 6-12 in inbred lines with fast kernel dehydration rate. We found a negative correlation between short amylopectin chains (DP 6-12) and the starch retrogradation rate. Hence, a low amount of amylopectin chains with DP 6-12 in the inbred lines with fast kernel dehydration rate was a plausible reason for their high short- and long-term retrogradation.