Corn Starch: Quality and Quantity Improvement for Industrial Uses

Characterization of Indian waxy and non-waxy maize germplasm for genetic differentiation through SNP genotyping

Waxy maize characterized by high amylopectin content resulting from a recessive wx1 gene, is important for both dietary and industrial applications, yet it suffers from low yields and limited breeding options. This study aims to develop a thorough understanding of the underlying genetics for successful hybridization experiments in waxy maize and the identification of potential cross combinations to derive high-yielding waxy maize hybrids in India. Here, we evaluated the kernel starch composition, yield-related traits, molecular diversity, kinship, LD, population structure, and selection signatures in a panel of 11 waxy and 37 non-waxy maize genotypes. The starch content in the panel ranged from 57.85 to 66.96%, while the amylopectin ranged from 70.65% to 96.32%. A significant positive correlation between kernel starch and amylopectin (0.39**) was identified suggesting the potential for simultaneous improvement of both these traits. The 48 maize lines were genotyped with 24,477 highly polymorphic single nucleotide polymorphisms (SNPs). Seventy-eight per cent of the pair-wise relative kinship values were less than or equal to 0, indicating minimal redundancy in the genomic composition of the inbred lines. The range of genetic distance among the pairs of waxy lines was 0.190 to 0.231 as compared to 0.076-0.264 in the non-waxy genotypes suggesting a greater genetic variation among the non-waxy genotypes. The mean LD value across the genome was 0.44. Two to four groups were identified using the model-based population structure, phylogenetic analysis and principal component analysis with no clear pattern of clustering based on the type of corn. Pairwise comparisons using the SNP dataset between waxy and non-waxy maize detected 27 loci under positive selection. The information generated in this study will be useful in the diversification of Indian waxy maize lines and the development of superior waxy maize hybrids.

Improving stabilization of α-tocopherol and α-tocopheryl acetate against oxidation, light and UV radiation by complexation with β-cyclodextrin and starch

Despite the remarkably high antioxidant activity of tocopherols, their applications in the food industry are limited because of their instability under various conditions. Complexes of α-tocopherol (α-TQ) or α-tocopheryl acetate (α-TQA) with β-cyclodextrin (β-CD) or starch were prepared and characterized by UV-vis, IR and thermal analysis. Oxidative stability of α-TQ and α-TQA against H2O2 was 74.7 and 88.8% respectively (576 h). However, stability increased to 82.9 and 100% for β-CD and 99.2 and 99.4% for starch complexes respectively, which indicates that starch is an excellent stabilizing host in addition to being an economic material. Stability of α-TQ and α-TQA under light conditions was dependent on their physical state; it was 55.3 and 82.9% (oil) but stability was lowered to 19.4 and 76.5% in solution (2.21 mM). In addition, exposure to UV irradiation decreased their stability to 39.2 and 85.0% as oil and 61.2 and 89.1% in solution respectively. However, the stability of all complexes remained > 99.0% under light and UV conditions. Accordingly, α-TQ, the natural and biologically active form, can be used as complex rather than α-TQA often used because of its higher stability. Docking revealed that both forms fit in β-CD with the side chain taking "U" conformation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-06011-2.

Alteration of the Morphological and Physicochemical Characteristics of Corn and Wheat Starch via Dry Heating with Whey Protein Isolates

This study investigated the impact of whey protein isolate (WPI) addition on the dry heat modification of corn (CS) and wheat starch (WS). Starches were treated under dry heating conditions at 130 °C for 2 and 4 h. The physicochemical and structural properties of the modified starches, such as color, particle size, thermal behavior (DSC), crystalline structure (XRD), and surface morphology (SEM), were analyzed. The results show that adding WPI significantly altered the gelatinization properties, surface morphology, and crystalline structure of both starches. DSC indicated that the gelatinization properties of starch/WPI mixtures varied, with corn starch showing a decreased gelatinization temperature and increased enthalpy, whereas wheat starch exhibited a more complex response, likely due to different structural changes. The XRD and FTIR results revealed WPI-enhanced crystallinity and structural changes, highlighting WPI-induced aggregation. Wheat starch, in particular, exhibited stronger interactions with WPI than corn starch, as evidenced by the accumulation patterns in the SEM images. The oil-binding capacity of native starches increased with dry heating and WPI addition, suggesting an improved hydrophobicity of starch granules. Dry heating and WPI addition significantly altered starch properties, highlighting the potential of thermal modulation to enhance starch-protein systems for targeted food applications.

Nanocurcumin-Based Sugar-Free Formulation: Development and Impact on Diabetes and Oxidative Stress Reduction

The objective of this study is the development of innovative nanocurcumin-based formulations designed for the treatment and prevention of oxidative stress and diabetes. Nanocurcumin was obtained through a micronization process and subsequently encapsulated within biopolymers derived from corn starch and fenugreek mucilage, achieving encapsulation rates of 75% and 85%, respectively. Subsequently, the encapsulated nanocurcumin was utilized in the formulation of sugar-free syrups based on Stevia rebaudiana Bertoni. The stability of the resulting formulations was assessed by monitoring particle size distribution and zeta potential over a 25-day period. Dynamic light scattering (DLS) revealed a particle size of 119.9 nm for the fenugreek mucilage-based syrup (CURF) and 117 nm for the corn starch-based syrup (CURA), with polydispersity indices PDIs of 0.509 and 0.495, respectively. The dissolution rates of the encapsulated nanocurcumin were significantly enhanced, showing a 67% improvement in CURA and a 70% enhancement in CURF compared with crude curcumin (12.82%). Both formulations demonstrated excellent antioxidant activity, as evidenced by polyphenol quantification using the 2.2-diphenyl 1-pycrilhydrazyl (DPPH) assay. In the evaluation of antidiabetic activity conducted on Wistar rats, a substantial reduction in fasting blood sugar levels from 392 to 187 mg/mL was observed. The antioxidant properties of CURF in reducing oxidative stress were clearly demonstrated by a macroscopic observation of the rats' livers, including their color and appearance.

Feasibility of replacing waxy rice with waxy or sweet-waxy corn viewed from the structure and physicochemical properties of starches

To explore the feasibility of substituting waxy rice with waxy or sweet-waxy corn, eight varieties of waxy and sweet-waxy corns were selected, including three self-cultivated varieties (Feng nuo 168, Feng nuo 211, and Feng nuo 10). Their starches were isolated and used as research objects, and commercially available waxy rice starch (CAWR) and waxy corn starch (CAWC) were used as controls. X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, rapid viscosity analyzer, and rotational rheometer were used to analyze their physicochemical and structural characteristics. The morphologies of all corn starch granules were generally oval or round, with significant differences in particle size distributions. All ten starches exhibited a typical A-type crystal structure; however, their relative crystallinity varied from 20.08% to 31.43%. Chain length distribution analysis showed that the A/B ratio of Jing cai tian nuo 18 and Feng nuo 168 was similar to that of CAWR. Peak viscosities of corn starches were higher than that of CAWR, except for Feng nuo 10, while their setback values were lower than that of CAWR. Except for Feng nuo 10, the paste transparency of corn starches was higher than that of CAWR (10.77%), especially for Jing cai tian nuo 18 (up to 24%). In summary, Jing cai tian nuo 18 and Feng nuo 168 are promising candidates to replace CAWR in developing various rice-based products.

Uncovering the mechanisms of how corn steep liquor and microbial communities minimize cadmium translocation in Chinese cabbage

Corn steep liquor-assisted microbial remediation has been proposed as a promising strategy to remediate cadmium (Cd)-contaminated soil. In this study, we determined Bacillus subtilis (K2) with a high cadmium (Cd) accumulation ability and Cd resistance. However, studies on this strategy used in the Cd uptake of Chinese cabbage are lacking, and the effect of the combined incorporation of corn steep liquor and K2 on the functions and microbial interactions of soil microbiomes is unclear. Here, we study the Cd uptake and transportation in Chinese cabbage by the combination of K2 and corn steep liquor (K2 + C7) in a Cd-contaminated soil and corresponding microbial regulation mechanisms. Results showed that compared to inoculant K2 treatment alone, a reduction of Cd concentration in the shoots by 14.4% and the dry weight biomass of the shoots and the roots in Chinese cabbage increased by 21.6% and 30.8%, respectively, under K2 + C7 treatment. Meanwhile, hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels were decreased by enhancing POD and SOD activity, thereby reversing Cd-induced oxidative damage. Importantly, inoculation of K2 would decrease the diversity of the microbial community while enhancing the abundance of dominant species. These findings provide a promising strategy for reducing the Cd accumulation in Chinese cabbage and recovering soil ecological functions.

An effective moisture interference correction method for maize powder NIR spectra analysis

The detection of maize starch content is of great significance for maize processing industry and near-infrared spectroscopy (NIRS) is an ideal rapid detection technology. However, the interference of moisture in maize is a bottleneck problem that affects the accuracy of NIRS quantitative analysis. In this study, we proposed methods based on external parameter orthogonalization (EPO) combined with wavelength selection algorithms to bring more accurate analytical results. Two groups of maize starch samples with different moisture content distributions were investigated to compare the predictive performance of NIRS models. The results showed that the model built using EPO combined with the synergy interval partial least squares (EPO-siPLS) algorithm exhibited the superior prediction accuracy, whose RMSEP/RMSEPck is improved by 9.7 % compared with that of siPLS model, 25.3 % compared with that of EPO-PLS, and 45.8 % compared with that of the PLS model. This study provides a more accurate and robust new method for rapid detection of maize starch and offers new insights for its application.

Rumen and fecal microbiomes are related to diet and production traits in Bos indicus beef cattle

Background

Ruminants harbor a complex microbial community within their gastrointestinal tract, which plays major roles in their health and physiology. Brazil is one of the largest producers of beef in the world and more than 90% of the beef cattle herds are composed of pure and crossbred Nelore (Bos indicus). Despite its importance to the Brazilian economy and human feeding, few studies have characterized the Nelore microbiome. Therefore, using shotgun metagenomics, we investigated the impact of diet on the composition and functionality of the Nelore microbiome, and explored the associations between specific microbial taxa and their functionality with feed efficiency and methane emission.

Results

The ruminal microbiome exhibited significantly higher microbial diversity, distinctive taxonomic profile and variations in microbial functionality compared to the fecal microbiome, highlighting the distinct contributions of the microbiomes of these environments. Animals subjected to different dietary treatments exhibited significant differences in their microbiomes' archaeal diversity and in the abundance of 89 genera, as well as in the functions associated with the metabolism of components of each diet. Moreover, depending on the diet, feed-efficient animals and low methane emitters displayed higher microbial diversity in their fecal microbiome. Multiple genera were associated with an increase or decrease of the phenotypes. Upon analyzing the functions attributed to these taxa, we observed significant differences on the ruminal taxa associated with feed efficient and inefficient cattle. The ruminal taxa that characterized feed efficient cattle stood out for having significantly more functions related to carbohydrate metabolism, such as monosaccharides, di-/oligosaccharides and amino acids. The taxa associated with methane emission had functions associated with methanogenesis and the production of substrates that may influence methane production, such as hydrogen and formate.

Conclusion

Our findings highlight the significant role of diet in shaping Nelore microbiomes and how its composition and functionality may affect production traits such as feed efficiency and methane emission. These insights provide valuable support for the implementation of novel feeding and biotechnological strategies.

Irradiation effects on characteristics and ethanol fermentation of maize starch

Maize starch was irradiated by a Co60 irradiator with different doses. The morphology and physicochemical properties of native and irradiated starches were investigated. Scanning electron microscopy showed that the shape and size of starch granules did not change after irradiation. However, the irradiated starch granules were easily destroyed by dissolution. Irradiation also caused the change of starch color, the decrease in the pH value, light transmittance, stability index, degree of polymerization, total sugar content, and the increase in the swelling index and the reducing sugar content. In this study, irradiated maize starch was also used as material for ethanol fermentation to investigate its potential as a pretreatment method. Results showed that the ethanol yield of cooked and raw starch fermentation using irradiated starch increased by 20.41 % and 5.18 %, respectively, and the ethanol concentration increased by 3 % and 2 %. This finding indicated that irradiation effectively improved the utilization rate of maize starch, making it an effective pretreatment method for ethanol fermentation.

Reinvention of starch for oral drug delivery system design

Starch is a polysaccharide with varying amylose-to-amylopectin ratios as a function of its biological sources. It is characterized by low shear stress resistance, poor aqueous/organic solubility and gastrointestinal digestibility which limit its ease of processing and functionality display as an oral drug delivery vehicle. Modulation of starch composition through genetic engineering primarily alters amylose-to-amylopectin ratio. Greater molecular properties changes require chemical and enzymatic modifications of starch. Acetylation reduces water solubility and enzymatic digestibility of starch. Carboxymethylation turns starch acid-insoluble and aggregative at low pHs. The summative effects are sustaining drug release in the upper gut. Acid-insoluble carboxymethylated starch can be aminated to provide an ionic character essential for hydrogel formation which further reduces its drug release. Ionic starch can coacervate with oppositely charged starch, non-starch polyelectrolyte or drug into insoluble, controlled-release complexes. Enzymatically debranched and resistant starch has a small molecular size which confers chain aggregation into a helical hydrogel network that traps the drug molecules, protecting them from biodegradation. The modified starch has been used to modulate the intestinal/colon-specific or controlled systemic delivery of oral small molecule drugs and macromolecular therapeutics. This review highlights synthesis aspects of starch and starch derivatives, and their outcomes and challenges of applications in oral drug delivery.

Insights into the Molecular Basis of Huanglongbing Tolerance in Persian Lime (Citrus latifolia Tan.) through a Transcriptomic Approach

Huanglongbing (HLB) is a vascular disease of Citrus caused by three species of the α-proteobacteria "Candidatus Liberibacter", with "Candidatus Liberibacter asiaticus" (CLas) being the most widespread and the one causing significant economic losses in citrus-producing regions worldwide. However, Persian lime (Citrus latifolia Tanaka) has shown tolerance to the disease. To understand the molecular mechanisms of this tolerance, transcriptomic analysis of HLB was performed using asymptomatic and symptomatic leaves. RNA-Seq analysis revealed 652 differentially expressed genes (DEGs) in response to CLas infection, of which 457 were upregulated and 195 were downregulated. KEGG analysis revealed that after CLas infection, some DEGs were present in the plant-pathogen interaction and in the starch and sucrose metabolism pathways. DEGs present in the plant-pathogen interaction pathway suggests that tolerance against HLB in Persian lime could be mediated, at least partly, by the ClRSP2 and ClHSP90 genes. Previous reports documented that RSP2 and HSP90 showed low expression in susceptible citrus genotypes. Regarding the starch and sucrose metabolism pathways, some genes were identified as being related to the imbalance of starch accumulation. On the other hand, eight biotic stress-related genes were selected for further RT-qPCR analysis to validate our results. RT-qPCR results confirmed that symptomatic HLB leaves had high relative expression levels of the ClPR1, ClNFP, ClDR27, and ClSRK genes, whereas the ClHSL1, ClRPP13, ClPDR1, and ClNAC genes were expressed at lower levels than those from HLB asymptomatic leaves. Taken together, the present transcriptomic analysis contributes to the understanding of the CLas-Persian lime interaction in its natural environment and may set the basis for developing strategies for the integrated management of this important Citrus disease through the identification of blanks for genetic improvement.

The addition of crosslinked corn bran arabinoxylans with different gelling characteristics was associated with the pasting, rheological, structural, and digestion properties of corn starch

Crosslinked corn bran arabinoxylan (CLAX) is a food hydrocolloid that can be applied to improve the physicochemical and digestion properties of starch. However, the impact of CLAX with different gelling characteristics on starch properties remains elusive. Here, high cross-linked arabinoxylan (H-CLAX), moderate crosslinked arabinoxylan (M-CLAX), and low crosslinked arabinoxylan (L-CLAX) were fabricated to investigate their effects on the pasting, rheological, structural, and in vitro digestion property of corn starch (CS). The results showed that H-CLAX, M-CLAX, and L-CLAX differently increased the pasting viscosity and gel elasticity of CS, with H-CLAX exhibiting the greatest effect. The structural characterization of CS-CLAX mixtures showed that H-CLAX, M-CLAX, and L-CLAX differently enhanced the swelling power of CS and increased the hydrogen bonds between CS and CLAX. Furthermore, the addition of CLAX (especially H-CLAX) significantly reduced both the digestion rate and extent of CS, probably due to the increased viscosity and the formation of the amylose-polyphenol complex. This study provided new insights into the interaction between CS and CLAX, and could help to develop healthier foods with slow starch digestibility.

Valorization of Starch to Biobased Materials: A Review

Many concerns are being expressed about the biodegradability, biocompatibility, and long-term viability of polymer-based substances. This prompted the quest for an alternative source of material that could be utilized for various purposes. Starch is widely used as a thickener, emulsifier, and binder in many food and non-food sectors, but research focuses on increasing its application beyond these areas. Due to its biodegradability, low cost, renewability, and abundance, starch is considered a "green path" raw material for generating porous substances such as aerogels, biofoams, and bioplastics, which have sparked an academic interest. Existing research has focused on strategies for developing biomaterials from organic polymers (e.g., cellulose), but there has been little research on its polysaccharide counterpart (starch). This review paper highlighted the structure of starch, the context of amylose and amylopectin, and the extraction and modification of starch with their processes and limitations. Moreover, this paper describes nanofillers, intelligent pH-sensitive films, biofoams, aerogels of various types, bioplastics, and their precursors, including drying and manufacturing. The perspectives reveal the great potential of starch-based biomaterials in food, pharmaceuticals, biomedicine, and non-food applications.