RESUMEN

This study comprehensively investigated the effects of high-temperature cooking (HT), complex enzyme hydrolysis (CE), and high-temperature cooking combined enzymatic hydrolysis (HE) on the chemical composition, microstructure, and functional attributes of soluble dietary fiber (SDF) extracted from corn bran. The results demonstrated that HE-SDF yielded the highest output at 13.80 ± 0.20 g/100 g, with enhancements in thermal stability, viscosity, hydration properties, adsorption capacity, and antioxidant activity. Cluster analysis revealed three distinct categories of SDF's physicochemical properties. Principal component analysis (PCA) confirmed the superior functional properties of HE-SDF. Correlation analysis showed positive relationships between the monosaccharide composition, purity, and viscosity of SDF and most of its functional attributes, whereas particle size and zeta potential were inversely correlated. Furthermore, a highly significant positive correlation was observed between crystallinity and thermal properties. These findings suggest that the HE method constitutes a viable strategy for enhancing the quality of SDF sourced from corn bran.

Asunto(s)

Fibras de la Dieta , Zea mays , Zea mays/química , Fibras de la Dieta/análisis , Hidrólisis , Viscosidad , Análisis Multivariante , Calor , Tamaño de la Partícula , Antioxidantes/química , Culinaria , Solubilidad

RESUMEN

The study examined the antihypertensive effect of peptides derived from pepsin-hydrolyzed corn gluten meal, namely KQLLGY and PPYPW, and their in silico gastrointestinal tract digested fragments, KQL and PPY, respectively. KQLLGY and PPYPW showed higher angiotensin I-converting enzyme (ACE)-inhibitory activity and lower ACE inhibition constant (Ki) values when compared to KQL and PPY. Only KQL showed a mild antihypertensive effect in spontaneously hypertensive rats with -7.83 and - 5.71 mmHg systolic and diastolic blood pressure values, respectively, after 8 h oral administration. During passage through Caco-2 cells, KQL was further degraded to QL, which had reduced ACE inhibitory activity. In addition, molecular dynamics revealed that the QL-ACE complex was less stable compared to the KQL-ACE. This study reveals that structural transformation during peptide permeation plays a vital role in attenuating antihypertensive effect of the ACE inhibitor peptide.

Asunto(s)

Inhibidores de la Enzima Convertidora de Angiotensina , Antihipertensivos , Digestión , Glútenes , Péptidos , Peptidil-Dipeptidasa A , Ratas Endogámicas SHR , Zea mays , Inhibidores de la Enzima Convertidora de Angiotensina/química , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/metabolismo , Antihipertensivos/química , Antihipertensivos/farmacología , Animales , Glútenes/química , Glútenes/metabolismo , Humanos , Zea mays/química , Zea mays/metabolismo , Ratas , Células CACO-2 , Péptidos/química , Péptidos/farmacología , Masculino , Digestión/efectos de los fármacos , Peptidil-Dipeptidasa A/química , Peptidil-Dipeptidasa A/metabolismo , Presión Sanguínea/efectos de los fármacos , Hipertensión/metabolismo , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Tracto Gastrointestinal/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/farmacología , Hidrólisis

RESUMEN

The fall armyworm, Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae), is a significant global pest, that exhibits 2 discernible strains, corn strain (CS) and rice strain (RS). After initial detection in the eastern hemisphere in 2016, the dominant strain was identified as RS based only on cytochrome C oxidase subunit I (COI) mitochondrial gene from limited samples from various countries, including Thailand. This study aimed to assess strain and haplotype variation in the S. frugiperda populations in Thailand using both mitochondrial COI and nuclear triosephosphate isomerase (Tpi) genes. Analyses of COI sequences (n = 105) revealed 2 predominant haplotypes, COICSh4 (82.86%) and COIRSh1 (17.14%), and the analyses of Tpi sequences (n = 99) revealed 6 haplotypes, with TpiCa1a (53.53%) being the most prevalent. Of the 98 caterpillar samples, the majority exhibited true CS (83.67%) for both genes. Meanwhile, interstrain hybrids, indicated by gene discordance, accounted for the minority (16.33%). Interestingly, despite the initial dominance of RS during the 2018 outbreak, the current study identified CS as the prevalent strain across all localities in Thailand. These findings suggested a shift in S. frugiperda dynamics in Thailand that was possibly influenced by factors, such as competitive exclusion principle, pesticide usage in rice cultivation, and preferences for corn over rice. Our study suggests a need to reexamine the previous reports of rice-strain dominance in various countries in the eastern hemisphere after the initial invasion.

RESUMEN

Phytic acid (PA) and malic acid (MA), as environmentally friendly, plant-based water-soluble acids, were applied to normal corn starch during dry heating at mildly acidic pH to improve its gelatinization and retrogradation behaviors. A significant increase in peak viscosity (5011-6338 mPa·s) was observed in starch treated with MA compared to native corn starch (1162 mPa·s). The treatment with PA and MA further increased the peak viscosity (8140-8621 mPa·s). The interactions of PA and MA with starch were analyzed using ICP-OES, FTIR, and 13C CP/MAS NMR. Swelling power and solubility increased in MA and PA + MA starches. After storage at 4 °C for 14 d, MA and PA + MA starches produced transparent and fluid gels without forming B-type crystals, which indicated inhibition of starch retrogradation by PA and MA treatments. In conclusion, dry heating with PA and MA produced starch with remarkably superior paste viscosity, swelling, and inhibition of retrogradation.

RESUMEN

A key aspect of sustainable bioeconomy is the recirculation of renewable, agricultural waste streams as substrates for microbial production of high-value compounds. One approach is the bioconversion of corn stover, an abundant maize crop byproduct, using the fungal maize pathogen Ustilago maydis. U. maydis is already used as a unicellular biocatalyst in the production of several industrially-relevant compounds using plant biomass hydrolysates. In this study, we demonstrate that U. maydis can grow using untreated corn stover as its sole carbon source. We developed a small-scale bioreactor platform to investigate U. maydis processing of corn stover, combining online monitoring of fungal growth and metabolic activity profiles with biochemical analyses of the pre- and post-fermentation residues. Our results reveal that U. maydis primarily utilizes soluble sugars i.e., glucose, sucrose and fructose present in corn stover, with only limited exploitation of the abundant lignocellulosic carbohydrates. Thus, we further explored the biotechnological potential of enhancing U. maydis´ lignocellulosic utilization. Additive performance improvements of up to 120 % were achieved when using a maize mutant with increased biomass digestibility, co-fermentation with a commercial cellulolytic enzyme cocktail, and exploiting engineered fungal strains expressing diverse lignocellulose-degrading enzymes. This work represents a key step towards scaling up the production of sustainable compounds from corn stover using U. maydis and provides a tool for the detailed monitoring of the fungal processing of plant biomass substrates.

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The possibility of different agrowastes to self-ignite under ambient condition, due to exothermic reactions between their surface molecules and air or other oxidizing agents which are conveyed into the void volume between the particles, exists. It is imperative to investigate the self-ignition ability of these harzadous waste products causing environmental pollution after the milling process to avoid sudden fire outbreaks. In this study, the self-ignition attributes of corn cob, wheat bran and rice husk residues in ambient air from biomass gasification was investigated by evaluating their self-ignition temperatures using DIN EN 15188:2021 standard and Frank-Kamenetzkii's theory of thermal explosion at varying basket volume. The results revealed decrease in the ignition temperature of dust samples as ignition time and dust basket volume were increased. Sample C (rice husk dust residue) was considered to be the most hazardous with respect to its propensity to self-heating possessing the lowest self-ignition temperature of 173 °C at 800 mL cubic mesh. Its moisture content and activation energy of 1.41 % and 46.52 kJ/mol respectively were the lowest. Its thermal conductivity, carbon content, heating value and bulk density of 0.07 W/mK, 78.98 wt%, 26,895 kJ/kg and 255.4 kg/m3 respectively were the highest. Correlation coefficient from the Arrhenius plot showing the self-ignition behaviour of dust samples using the model of Frank-Kamenetzkii were 0.9976, 0.9910 and 0.9962 for corn cob, wheat bran and rice husk residues respectively. In conclusion, the data presented are effective in predicting the self-ignition ability of corn cob, wheat bran and rice husk residues in ambient air from biomass gasification in order to prevent sudden fire attack that may arise based on storage of their dust particles in food processing industries.

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Baby corn, characterized by its high water activity and elevated respiration rate, poses a formidable obstacle to prolonged storage under standard ambient conditions and necessitates specialized treatments for transportation to distant locations. One of the primary postharvest challenges associated with baby corn is the occurrence of brown pigment formation because of enzymatic browning at the apex of its immature ovules, cut surfaces, and silk attached to the young ears. The present study was undertaken to investigate the effect of different blanching treatments on peroxidase inactivation, physicochemical properties, and functional properties of baby corn. The treatments applied were hot water blanching (HWB) at temperatures ranging from 70°C to 90 °C for 30-240 s, steam blanching (SB) for 30-240 s, and microwave blanching (MWB) at power levels of 360 W-900 W for 30-300 s. Results indicated that 90 % peroxidase enzyme inactivation occurred under different methods as 90 °C for 60 s for HWB, 100 °C for 60 s for SB, and 540 W for 30 s for MWB. These blanching methods have shown significant effects on the properties under investigation. MWB demonstrated the highest retention of ascorbic acid (94.15 %) and minimal color changes (ΔE = 5.72) in comparison to hot water and steam blanching. Similarly, the result for total flavonoid content for 540 W, 90 °C and 100 °C for 30, 60, and 60 s were found to be 3.01,1.99 and 2.10 mg QE/100g, phenols 48.98, 47.99 and 48.03 mg GAE/100g and DPPH (%) 42.55, 34.20 and 37.08 % respectively. The findings suggest that microwave blanching of baby corn at 540 W for 30 s holds promise to inactivate the peroxidase enzyme with better retention of physicochemical and functional properties.

RESUMEN

The utilization of cold plasma can be used as an alternative method to modify the properties of starch. This research aimed to examine the use of cold plasma technology to alter the structure of corn starch and investigate how its functionality could be improved using a food model (milk dessert). Modified corn starch by plasma technology under different gas contents (dielectric-barrier discharge (DBD)) (95 % argon+5 % hydrogen (DBD1) and 90 % argon+10 % oxygen (DBD2)) was compared to the control sample of corn starch. The physicochemical characteristics of modified corn starch, DSC, XRD, SEM and FTIR tests were evaluated. The findings demonstrated that corn starch had significantly higher solubility, transparency, ash, oil absorption capacity (OAC), and resistant starch (RS) when exposed to cold plasma under the test circumstances compared to the control sample. SEM analysis confirmed that plasma affected the surface of starch granules, making the surface changes more pronounced when oxygen was added to the treatment. It was concluded that the sample should be treated with plasma containing 90 % argon and 10 % oxygen (as the best sample). The best sample (modified corn starch) was used to prepare a milk dessert as a food model, and considerable differences were found between the modified starch treated sample and control samples in terms of moisture, brix, syneresis, and organoleptic properties (p < 0.05).

RESUMEN

Because of eco-friendliness, biodegradability and ease of modification, cellulose is deemed as alternative to unrenewable petroleum resources. Nonetheless, it is more indispensable to exploit corn cob cellulose produced from agricultural waste residue as supportive materials in green catalysis. In this study, a new magnetically benzimidazole functionalized cellulose/Fe3O4 derived from corn cob cellulose as a stabilizer agent (Fe3O4@CL-NHC) was prepared, and palladium was immobilized on this stabilizer (Fe3O4@CL-NHC-Pd). The catalyst was fully characterized by different techniques including TEM, SEM, and XPS analyses, etc. The abundant hydroxyl groups of cellulose provided uniform dispersion and high stability of palladium, while Fe3O4 as a support offered simple magnetic separation. High efficiency (up to 99 %) was demonstrated by this biocatalyst under green conditions in relatively short reaction times towards Suzuki reactions. Due to collaborative interactions of N-heterocyclic carbene and hydroxyl groups with palladium, the synthesized complex prevented metal leaching effectively (<1 %). Moreover, the magnetic property of this catalyst (43.0 emu g-1) provides facile recovery of this composite from the reaction mixture with great ease for several times, which overcomes issues of complicated work-up separation. This work offers a promising avenue to enriching the application of biopolymer from agricultural residue in the potential organic transformations.

RESUMEN

Land suitability (LS) classifications are essential for efficient and sustainable agricultural land use. With climate change, future LS classifications are necessary to ensure that crop growth remains sustainable and prevents land degradation. This study develops a current LS classification for rainfed corn (Zea mays) growth in the state of Georgia, USA, which is validated using historical census data on yield, acres planted, and corn crop lost. Significant (p < 0.05) differences were found between yield, acres planted, and crop loss percentage across LS classes for many years. Soil factors (Ph and soil texture) showed significant differences in fewer years compared to climate and topography factors, as soil factors can be altered by management practices such as liming and irrigation. Future LS classes determined by climate factors indicated a shift to the northwest of 150-300 km by the year 2100 based on the RCP4.5 or RCP8.5 emissions scenarios. The northwards shift in more suitable land due to rising maximum temperatures is expected to limit rainfed corn growth in Georgia in the future. As urban areas become more suitable for corn growth, farmers may need to plant crops earlier, irrigate, or switch to different crops. These results have important implications for agricultural planning and policy in the state of Georgia.

RESUMEN

Fagao is one of China's traditional gluten-free staple foods made with rice or corn flour. Corn Fagao prepared by co-fermentation with sourdough and yeast exhibits better quality and less staling compared to traditional yeast-fermented Fagao. The physicochemical properties of corn Fagao batter during sourdough-yeast co-fermentation were investigated. The results showed that compared with yeast fermentation, the gas production and viscosity of the batter increased with co-fermentation. The co-fermented batter showed a higher hydrolysis of starch and less amylose content. The integrity of starch granules in the co-fermented batter was damaged more seriously, and the crystallinity and short-range ordered structure were less than in the yeast-fermented batter, even though the crystal structure type of starch did not obviously change. The peak viscosity, minimum viscosity, final viscosity, decay value, and recovery value of the corn batter were reduced by co-fermentation, which improved the thermal stability of the batter and slowed down the aging. Co-fermentation also resulted in a more pronounced reduction in protein subunit content than yeast fermentation. The changes in the physicochemical properties of the corn Fagao batter help explain the improvement in quality of corn Fagao made from the co-fermentation method and may provide theoretical references for co-fermentation with sourdough and yeast to other gluten-free foods.

RESUMEN

Although graphene oxide (GO) has extensive recognized application prospects in slow-release fertilizer, plant pest control, and plant growth regulation, the incorporation of GO into nano herbicides is still in its early stages of development. This study selected a pair of sweet corn sister lines, nicosulfuron (NIF)-resistant HK301 and NIF-sensitive HK320, and sprayed them both with 80 mg kg-1 of GO-NIF, with clean water as a control, to study the effect of GO-NIF on sweet corn seedling growth, photosynthesis, chlorophyll fluorescence, and antioxidant system enzyme activity. Compared to spraying water and GO alone, spraying GO-NIF was able to effectively reduce the toxic effect of NIF on sweet corn seedlings. Compared with NIF treatment, 10 days after of spraying GO-NIF, the net photosynthetic rate (A), stomatal conductance (Gs), transpiration rate (E), photosystem II photochemical maximum quantum yield (Fv/Fm), photochemical quenching coefficient (qP), and photosynthetic electron transfer rate (ETR) of GO-NIF treatment were significantly increased by 328.31%, 132.44%, 574.39%, 73.53%, 152.41%, and 140.72%, respectively, compared to HK320. Compared to the imbalance of redox reactions continuously induced by NIF in HK320, GO-NIF effectively alleviated the observed oxidative pressure. Furthermore, compared to NIF treatment alone, GO-NIF treatment effectively increased the activities of superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) in both lines, indicating GO induced resistance to the damage caused by NIF to sweet corn seedlings. This study will provides an empirical basis for understanding the detoxification promoting effect of GO in NIF and analyzing the mechanism of GO induced allogeneic detoxification in cells.

Asunto(s)

Antioxidantes , Clorofila , Grafito , Herbicidas , Fotosíntesis , Compuestos de Sulfonilurea , Zea mays , Fotosíntesis/efectos de los fármacos , Clorofila/metabolismo , Zea mays/efectos de los fármacos , Zea mays/metabolismo , Zea mays/crecimiento & desarrollo , Compuestos de Sulfonilurea/farmacología , Compuestos de Sulfonilurea/toxicidad , Antioxidantes/metabolismo , Grafito/toxicidad , Herbicidas/toxicidad , Herbicidas/farmacología , Piridinas/farmacología , Fluorescencia , Superóxido Dismutasa/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo

RESUMEN

BACKGROUND: Diets with high inclusion of corn co-products such as corn fermented protein (CFP) may contain excess Leu, which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin synthesis. However, we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val, Trp, and (or) Ile. METHODS: Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a completely randomized design, with 4 pigs per pen and 8 replicate pens per treatment. A corn-soybean meal diet and 2 basal diets based on corn and 10% CFP or corn and 20% CFP were formulated. Seven additional diets were formulated by fortifying the basal diet with 20% CFP with Ile, Trp, Val, Ile and Val, Ile and Trp, Trp and Val, or Ile, Trp and Val. A two-phase feeding program was used, with d 1 to 14 being phase 1 and d 15 to 28 being phase 2. Fecal scores were recorded every other day. Blood samples were collected on d 14 and 28 from one pig per pen. On d 14, fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids, ammonium concentration, and microbial protein. These pigs were also euthanized and ileal tissue was collected. RESULTS: There were no effects of dietary treatments on any of the parameters evaluated in phase 1. Inclusion of 10% or 20% CFP in diets reduced (P < 0.05) final body weight on d 28, and average daily gain (ADG) and average daily feed intake (ADFI) in phase 2 and for the entire experimental period. However, pigs fed the CFP diet supplemented with Val, Ile, and Trp had final body weight, ADFI, ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control diet. Fecal scores in phase 2 were reduced (P < 0.05) if CFP was used. CONCLUSIONS: Corn fermented protein may be included by up to 20% in diets for weanling pigs without affecting growth performance, gut health, or hindgut fermentation, if diets are fortified with extra Val, Trp, and Ile. Inclusion of CFP also improved fecal consistency of pigs.

RESUMEN

This study presents an innovative approach to eco-friendly synthesis and utilization of copper nanoparticles (CuNPs) for photocatalytic applications, employing waste corn husk fibers as sustainable catalyst support. The synthesis of CuNPs was achieved through a green synthesis method utilizing myrtle extract. Subsequently, the remarkable photocatalytic activity of the CuNPs explored (76% removal efficiency of Crystal Violet), showcased their potential in environmental remediation applications. Furthermore, the immobilization of CuNPs onto waste corn husk fibers was investigated, aiming to develop a novel composite material with enhanced catalytic performance. A distinctive approach was introduced by immobilizing CuNPs onto fibers derived from corn husks, and waste biomass material, leading to a significant enhancement in photocatalytic efficiency, surpassing 95.1%. Furthermore, bioactivity evaluation studies revealed the significant antioxidant, antidiabetic, DNA fragmentation, cell viability, antibiofilm and antimicrobial properties of CuNPs. The antioxidant ability was determined at 100 mg/L as 87.12%. The most powerful antimicrobial activity of CuNP was found as a MIC value of 8 mg/L against E. faecalis. The cell viability inhibition of CuNP was 90.05% at 20 mg/L. CuNP exhibited biofilm inhibition activity at different concentrations. The antibiofilm ability was investigated against Staphylococcus aureus compared to Pseudomonas aureginosa. While the DNA cleavage activity of CuNP observed double-strand breaks at 50 and 100 mg, complete fragmentation occurred at 200 mg concentrations. The bioactivity of the synthesized CuNPs shed light on their potential biomedical applications. The synthesized CuNPs are characterized using various analytical techniques to elucidate their structural and morphological properties. Fourier-transform infrared (FTIR) analysis provided insights into the chemical composition and surface properties of the synthesized materials. EDS analysis confirmed their successful integration into waste corn husk fibers. Overall, this interdisciplinary study highlights the potential of CuNPs immobilized on waste corn husk fibers for addressing environmental pollution, advancing sustainable technologies and paving the way for the development of efficient catalysts with diverse functionalities.

RESUMEN

Kuey teow is one of the delicacies of Guangdong, China and is a gluten-free noodle dish made from rice. It has a short storage period and extending the shelf life by quick freezing induces quality deterioration due to temperature fluctuations. To improve its freeze-thaw frozen storage quality, this paper examined the effects of hydroxypropyl corn starch (HCS), guar gum (GG), and compound phosphates (CP) on the quality of quick-frozen kuey teow during freeze-thaw cycles. The mechanism was investigated by identifying changes in the moisture status, aging degree of the starch, and textural and cooking characteristics. The results showed that all three additions improved the toughness, chewiness and steaming characteristics of the kuey teow, with CP significantly enhancing chewiness. XRD and FTIR results revealed that GG more significantly inhibited the decrease of starch crystallinity, while HCS inhibited starch aging. GG, HCS and CP all improved the hydration characteristics and water holding capacity of rice starch. GG enhances the ability of starch to bind more tightly with water, resulting in a more uniform water distribution and a more continuous and tight structure of the kuey teow. This study will provide a theoretical basis for compounding and optimizing the quick-freezing of kuey teow.

RESUMEN

In plants, sugar metabolism involves a complex interplay of genetic, molecular and environmental factors. To better understand the molecular mechanisms underlying these processes, we utilized a multi-layered approach that integrated transcriptomic and metabolomic datasets generated from multiple different varieties of sweet corn. Through this analysis, we found 2533 genes that were differentially expressed in the immature kernel tissues of sweet corn, including genes involved in transcriptional regulation, sugar metabolism, primary metabolism, and other processes associated with adaptability of sweet corn. We also detected 31 differential metabolites among the three types of sweet corn. Utilizing an integrated approach encompassing transcriptomics and eGWAS, we elucidated the transcriptional regulatory patterns governing these differential metabolites. Specifically, we delved into the transcriptional modulation of malate- and ubiquitin-associated genes across a range of sweet corn varieties, shedding new light on the molecular mechanisms underlying their regulation. This study provides a framework for future research aimed at improving the current understanding of sugar metabolism and regulatory gene networks in sweet corn, which could ultimately lead to the development of novel strategies for crop improvement.

RESUMEN

This work proposes an evaluation of the Crystalline Index (CrI) in function of the bleaching process employed during cellulose extraction from corn husk, for further characterization using CP/MAS 13C NMR, XRD, and FT-IR. In that sense, CrI values were calculated by FT-IR and the bands associated with the crystalline and amorphous regions were observed at 1424 cm-1 and 896 cm-1, respectively. Similarly, the signals due to ordered (89.1 ppm) and disordered (84.2 ppm) cellulose chains were detected by solid-state 13C NMR, while the Segal equation was only used for comparison purposes. Additionally, PCA studies showed consistent results attributed to the crystalline region in cellulose domains analyzed by both, FT-IR and solid-state 13C NMR. The results revealed the coexistence of cellulose I/cellulose II and its effect on CrI, as well as the incomplete mercerization process, in some cases non-cellulosic residues can cause an overestimation of CrI. Additionally, the thermal stability and the glass transition temperature were determined by TGA/DTA and DSC analyses. Finally, a partially fibrillated-network morphology with a diameter of 20.47 ± 2.77 µm was observed in cellulose bleached with peracetic acid, whereas organosolv method provides flexible and clean microfibrils with diameter sizes between 10 and 9 µm.

RESUMEN

This study investigated the effects of ultrasonic and three chemical individual and dual modification treatments on corn starch's physicochemical, thermal, and rheological properties. Ultrasonication and the three chemical treatments disrupted the starch granules with a decrease in particle size and a significant increase in the ζ-potential. The hydrophilicity of ultrasonic-oxidized dual-modified starch (U-O-CS) was the highest, at 0.854 g/g. The lipophilicity of ultrasonic-esterified dual-modified starch (U-E-CS) was the highest, at 1.485 g/g. The gelatinization temperature of ultrasonic, oxidation, and cross-linking modified starches increased significantly, with cross-linking starches being the largest. Oxidative treatment significantly decreased the starch's G' and G" and weakened the textural properties. The rheological properties of U-O-CS were further weakened. The G' of the starch decreased after the esterification treatment, while the G" increased, and the textural properties were cut. The maximum rheological and textural properties were obtained for crosslinked modification, with a hardness value of 284.70 g.

RESUMEN

Endowing biodegradable plastics with easy recyclability can reduce competition with food resources and further enhance their environmental friendliness. In this work, 4-carboxyphenylboronic acid was grafted onto the side chains of hydroxyethyl cellulose and compounded with inexpensive cornstarch. Upon the introduction of tannic acid, stable and reversible borate ester bond rapidly formed, yielding composite biodegradable plastic films with outstanding mechanical properties and facile recyclability. The formation of a dynamic cross-linked network mitigates the aggregation of gelatinized starch molecules, enhancing the flexibility and durability of the crosslinked film. Testing revealed that while maintaining high tensile strength, the elongation at break of the crosslinked film increased by 952.86 %. The static water contact angle was improved from 32.74° to 78.82°, with a change of <5° within 1 min, demonstrating enhanced water resistance. Excellent antioxidant and thermal stability were also characterized, the crosslinked film can be easily dissolved by heating in water at pH = 6.5 and reshaped in water at pH = 7.2. After five times of regeneration, the tensile strength loss was as low as 5.68 %. This eco-friendly and efficient recycling process is promising during green chemistry.

RESUMEN

The real-time monitoring of corn yield by a combine harvester is a critical data source for constructing the yield histogram, which significantly benefits precision management and decision-making in modern precision agriculture. While widely used, the current photoelectric sensor-based yield monitoring method has limitations. It detects the corn height on each scraper and calculates the yield through a geometric formula. However, it neglects the noticeable difference in the corn stacking patterns affected by factors such as feeding volume, terrain, and driving speed. This oversight often results in low accuracy and poor stability in the prediction of corn yield, highlighting the need for a more advanced approach. To resolve this, we employ EDEM discrete element simulation to demonstrate the large difference of corn stacking patterns on the scraper of the elevator corresponding to feeding volume. Then, we develop a real-time monitoring system on our self-developed double elevator testing rig for carrying out a composite dataset for training three machine learning algorithm-based models, namely Deep Neural Networks (DNN), Gradient Boosting Machine (GBM), and Random Forest (RF). Importantly, these models have undergone rigorous validation under various feeding volumes, ensuring their robustness and reliability. The auxiliary elevator speed is meticulously set at 150r/min, 225r/min, and 450r/min, providing a comprehensive performance assessment. The results denote that the DNN model performs best and is stable, with a coefficient of determination (R2) of 0.998, root mean square error (RMSE) of 0.526, and mean absolute error (MAE) of 0.425. The paper also performs field experiments to test the proposed three prediction models and the system. The results also denote the DNN-based prediction model's best performance for the lowest relative error of 2.29% and the highest average accuracy of 97.85%. Consequently, the proposed real-time corn yield monitoring system achieves high accuracy and reliability for the combine harvester applications.