Investigating the properties and agronomic benefits of onion peel and chicken feather-derived biochars.

Biochar production from unconventional biomass, specifically onion peel (OP) and chicken feathers (CF), was investigated in this study. Two distinct biochars were produced by doping each biomass with the other, with the aim of exploring the synergistic effects of different feedstock combinations on biochar properties. The biochar production process was conducted using a retort heating method and characterized using several techniques. A yield of 36 % was obtained for OP-doped biochar (OP92CF8-BC) and 23 % for CF-doped biochar (F92OP8-BC). Fourier Transform Infrared Spectroscopy analysis revealed characteristic functional groups from cellulose, hemicellulose, and lignin in OP92CF8-BC, while CF92OP8-BC displayed keratin-related peaks. Scanning Electron Microscopy imaging showed surface morphology differences, with OP92CF8-BC exhibiting a rougher and more porous structure compared to CF92OP8-BC. Energy-Dispersive X-ray Spectroscopy analysis confirmed the elemental composition, with OP92CF8-BC having higher carbon, calcium, and sulfur contents and CF92OP8-BC having higher nitrogen and oxygen contents. The biochar had specific surface areas of 342.4 and 200.80 m2/g for OP92CF8-BC and CF92OP8-BC, respectively. According to the results, using biochar treatments-more especially, CF92OP8-BC-can significantly enhance cob weight. This could be good for agricultural productivity. These findings highlight the influence of feedstock composition on the properties of biochar and provide insights for its potential applications in soil amendment and pollutant removal.

Levels of organochlorine pesticides in onion and tomato samples from selected towns of Jimma Zone, Ethiopia.

This study aimed to determine residues of organochlorine pesticides (OCPs) in tomato and onion samples collected from selected markets in the Jimma zone. A QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method was used for sample preparation followed by gas chromatography-mass spectrometry (GC-MS) for OCPs analysis. The method used showed wide linear ranges from 5-50 µg/L for all eight pesticides, with R2 values ≥ 0.992. The LOD values for the pesticides tested ranged from 0.14 µg/kg for p,p'-DDE to 2.40 µg/kg for p,p-DDT. LOQ values ranged from 0.46 µg/kg for p,p-DDE to 8.32 µg/kg for p,p'-DDT. The recoveries ranged from 74.84 - 109.45 % except for ß-BHC (67.82 %). While most of the OCPs in the onion and tomato samples met European Union (EU) and Codex standards, some exceeded the limits. Methoxychlor and p,p'-DDT in onions, and methoxychlor, p,p'-DDT, α-BHC, and δ-BHC in some tomatoes, were detected above the permitted levels. Specific OCPs were not detected in some samples including aldrin in Meki Tomato (Mek-T), γ-chlordane in Agaro Tomato (Ag-T), and p,p'-DDE in Gera Tomato (Ger-T). The residual concentrations of OCPs varied among the samples. Among tomatoes, Gera had the highest percentage of detected OCPs contaminants (37 %), followed by Agaro (34.34 %) and Meki (28.55 %). Similarly, Sire onion (SrO) had the highest percentage of detected OCPs (28 %) compared to Minjer (25.16 %), Shewa Robit (25.10 %), and Sudan onion (22.25 %). In conclusion, most tomato and onion samples analyzed in this study contained OCP residues highlighting the importance of conducting a consumer health risk assessment.

Unveiling primary intracranial eosinophilic angiocentric fibrosis: A rare case report and diagnostic dilemmas.

Eosinophilic angiocentric fibrosis (EAF) is a rare, benign fibroinflammatory condition primarily affecting the sinonasal and upper respiratory tract, with a few cases reported beyond these regions. Primary intracranial EAF is rare. To date, only one case of intracranial EAF has been reported; ours is the second. This case report presents a case of EAF in a 55-year-old man, initially misdiagnosed as meningioma based on clinical and radiological features. The patient complained of a persistent dull headache for six months without associated neurological symptoms. Brain magnetic resonance imaging revealed a dural-based lesion with characteristics suggestive of meningioma. However, histopathological examination post-surgical resection revealed a nodular vascular lesion with concentric angiocentric fibrosis, a distinctive onion skin pattern, and an inflammatory infiltrate rich in eosinophils, plasma cells, and histiocytes. Immunohistochemistry ruled out IgG4-related disease, and other systemic disorders were ruled out based on combined clinical and histological features. This case underscores the need for considering EAF in the differential diagnosis of dural-based lesions. Awareness of its potential mimicking of meningioma is crucial for accurate diagnosis and appropriate management, emphasizing the importance of histopathological examination in challenging cases.

Synthesis of some polyphenolics from contents of onion skin and discovery of the promoter effect on barley germination.

Facile synthesis and characterisation of three natural compounds and their two synthetic analogues based on onion skin content were performed. Both OSE and 2,4,6-trihydroxyphenylglyoxylic acid was induced effect on cell proliferation during barley germination with a difference of approximately %4 compared to the control group.

Optimizing plant growth, nutrient uptake, and yield of onion through the application of phosphorus solubilizing bacteria and endophytic fungi.

Introduction: The application of mineral fertilizers deteriorates soil properties and affects crop yield and nutritional properties. However, plant growth-promoting microorganisms (PGPM- Serendipita indica, phosphorus solubilizing bacteria (PSB), and vesicular arbuscular mycorrhizae (VAM)) have great potential to reduce fertilizers and improve soil fertility, crop yield, and nutrient uptake and mitigate the environmental effect of mineral fertilizers. Material and methods: Hence, a field experiment was conducted involving nine treatments to evaluate the effects of PGPM along with 50% or 100% of the recommended dose of fertilizers on plant growth, soil fertility, nutrient uptake, and onion productivity. Results and discussion: Results indicated that 100% RDF combined with S. indica or PSB led to improved plant growth, and higher nutrient concentrations in both leaves and bulbs of onions compared to RDF alone. Moreover, the application of 100% RDF with S. indica increased total dry matter yield by 11.5% and 7.6% in the 2018-2019 and 2019-2020 seasons, respectively, compared to 100% RDF alone. This treatment also resulted in the highest nutrient uptake, with N uptake increasing by 6.9%-29.9%, P by 13.7%-21.7%, K by 20.0%-23.7%, and S by 18.1%-23.4%. Additionally, the combination of 100% RDF with S. indica inoculation led to a notable increase in bulb yield, with increments of 16.2% and 13.9% observed in 2018-2019 and 2019-2020, respectively, compared to 100% RDF alone. Similarly, the application of 100% RDF along with PSB inoculation resulted in an increase in bulb yield by 7.2% and 9.4% in the respective years. However, VAM did not exhibit satisfactory performance or improvements in the onion crop. Conclusion: Overall, the study suggests that combining 100% RDF with S. indica or PSB can enhance onion productivity and nutrient use efficiency. The present study may open a new avenue of PGPM application in enhancing onion yield and improving the bulb quality as well as soil health. However, field trials across different regions and soil types are necessary to validate these findings for practical adoption by farmers.

Protective potential of onion eco-extract: safeguarding chicken patties from oxidative deterioration.

Onions contain valuable phytochemical compounds, including quercetin derivatives. This study explores the potential of onion extract as a natural additive in chicken patties. The optimized conditions involved sonication at 80% for 5 min with a 75% ethanol concentration. The onion extract exhibited total phenolic and flavonoid compound values of 255.63 mg GAE g-1 DR and 196.87 mg QE g-1 DR, respectively. The antioxidant activity of the onion extract was characterized by an IC50 of 12.74 µg/mL. This onion extract was dominated by quercetin derivatives (quercetin 4'-O-ß-glycoside and quercetin-3-O-ß-glycoside and quercetin-3,4'-O-ß-diglycoside). Chicken patties treated with 2% onion extract exhibited superior pH stability, lowest thiobarbituric acid reactive substances level (0.40 mg/kg) and peroxide index (0.77 mEq O2/kg meat) and maintained color stability. Comparative analysis with BHT demonstrated the efficacy of onion extract in reducing lipid oxidation. These findings highlight the potential of a 2% onion extract as effective ingredient for enhancing the quality of chicken products.

Climate change impacts on Allium crop production: Insights from long-term observations in South Korea.

Climate change is an imminent threat, particularly affecting agricultural productivity, which relies heavily on weather conditions. Understanding the specific impacts of climate change on key crops is crucial for developing effective adaptation strategies to ensure food security. The growth patterns of onions and garlic were observed at over ten different locations in South Korea, and the yield data from the past 40 years were analyzed. The yield was significantly correlated with temperature and strongly affected by the frequent and unexpected patterns of precipitation. The increase in mean temperature during winter and the spatial and temporal concentration of precipitation are expected to be the most influential factors for Allium crop production in the future. In addition, the yields of onions and garlic can serve as good indicators for predicting the impacts of weather on agricultural productivity, given their extended cultivation periods and significant correlations with temperature and precipitation. As climate change scenarios become available, the results of this study can serve as a basis for predicting changes in agricultural production in the future and identifying opportunities to adapt cultivation systems for food security.

Development of a sequential sampling plan for classifying Thrips tabaci (Thysanoptera: Thripidae) populations in onion fields.

Onion thrips, Thrips tabaci Lindeman, is a global pest of onion crops, causing substantial economic damage by diminishing bulb yields and transmitting plant pathogens. Insecticides are used to manage T. tabaci infestations with control decisions traditionally based on action thresholds that require visually counting thrips on a fixed, predetermined number of onion plants per field. However, this approach for treatment decisions is inefficient when thrips populations are well above or below the action threshold. The aim of this research was to develop a sequential sampling plan that would provide a rapid and reliable classification of thrips populations in commercial onion fields above or below prespecified management thresholds. The study was conducted in a total of 24 commercial onion fields in New York in 2021 and 2022. Taylor's power law and Wald's Sequential Probability Ratio Test were used in concert to develop each sampling plan. Simulated and historical field data of thrips populations were used to further validate the efficacy of each sampling plan. Results demonstrated the sequential sampling plan required an average of 78% fewer samples to make a control decision compared with the traditional fixed-sampling approach. Treatment decisions were reached in 72% of cases after inspecting only 10 plants, while only 6% of the cases required examining more than 25 plants. Comparisons with fixed-sample sizes ranging from 23 to 68 plants revealed a 96% agreement in decision-making and a 78% reduction in sampling effort when using the sequential sampling plans.

Concurrently boosted oxygen reduction/evolution electrocatalysis over highly loaded CoNi/onion-like carbon hybrid nanosheets.

Balancing the bicatalytic activities and stabilities between oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a critical yet challenging task for exploring advanced rechargeable Zinc-air batteries (ZABs). Herein, a hybrid nanosheet catalyst with highly dispersed and densified metallic species is developed to boost the kinetics and stabilities of both ORR and OER concurrently. Through a progressive coordination and pyrolysis approach, we directly prepared highly conductive onion-like carbon (OLC) accommodating dense ORR-active CoNC species and enveloping high-loading OER-active CoNi-synergic structures within a porous lamellar architecture. The resultant CoNi/OLC nanosheet catalyst delivers better ORR and OER activities showcasing a smaller reversible oxygen electrode index (ΔE = Ej10 - E1/2) of 0.71 V, compared to state-of-the-art Pt/C-RuO2 catalysts (0.75 V), Co/amorphous carbon polyhedrons (0.80 V), NiO nanoparticles with higher Ni loading (1.00 V), and most CoNi-based bifunctional catalysts reported so far. The rechargeable ZAB assembled with the developed catalyst achieves a remarkable peak power density of 270.3 mW cm-2 (172 % of that achieved by Pt/C + RuO2) and ultrahigh cycling stability with a negligible increase in voltage gap after 800 h (110 mV increase after 200 h for a Pt/C + RuO2-based battery), standing the top level of those ever reported.

Exploring the therapeutic potential of the oxygenated monoterpene linalool in alleviating saline stress effects on Allium cepa L.

Sodium chloride (NaCl) can cause oxidative stress in plants, which represents a potential obstacle to the development of monocultures worldwide. Onion (Allium cepa L.) is a famous vegetable consumed and used in world cuisine. In the present study, we analyzed the influence of soil physicochemical profile and the remedial capacity of linalool on seed emergence, roots, and leaf growth in onions subjected to salt stress, as well as its in vivo and in vitro antioxidant potential, Fe2+chelating activity, and reducing power of Fe3+. The outcome of the soil analysis established the following order of abundance: sulfur (S) > calcium (Ca) > potassium (K) > magnesium (Mg) > sodium (Na). NaCl (150 mM) significantly reduced the emergence speed index (ESI), leaf and root length, while increasing the peroxidation content. The length of leaves and roots significantly increased after treatment with linalool (300 and 500 µg/mL). Our data showed negative correlations between seed emergence and K+ concentration, which was reversed after treatments. Linalool (500 µg/mL) significantly reduced oxidative stress, but increased Fe2+ concentration and did not show potential to reduce Fe3+. The in vivo antioxidant effect of linalool is thought to primarily result from an enzymatic activation process. This mechanism underscores its potential as a therapeutic agent for oxidative stress-related conditions. Further investigation into this process could unveil new avenues for antioxidant therapy.

Aspects of quercetin stability and its liposomal enhancement in yellow onion skin extracts.

Quercetin is a flavonoid that occurs in many types of fruit and vegetables and is stable for no longer than 4.5 h in the investigated pH range (6.0-8.0), even at 4 °C in the dark. At higher temperatures, the degradation/oxidation process is much faster. Simple but effective proliposomal encapsulation was used to protect the quercetin from environmental conditions such as pH. With this approach, 65 to 90% of pure quercetin and quercetin-rich onion extract was kept after >60 days under conditions that favoured its oxidation (pH 7.4). In addition, the encapsulated quercetin decreases the lipid peroxidation induced by pulsed UV light by >50%. At a mass ratio of 1:100 quercetin to lipids (w/w), the liposomes remained intact in solutions for six months. Quercetin in lipid bilayers simultaneously protects the unsaturated lipids from peroxidation.

DFT simulated Quercetin imprinted polymer: Selective recovery of Quercetin from onion solid waste.

Onion peels (OP) are byproduct of food processing industries that poses economic and environmental challenges. However, being rich source of bioactive compounds like Quercetin (Qt), a polyphenolic antioxidant with potential health benefits, harnessing value from such waste can imbibe sustainable practices and protect environment. With this view, the present study targets selective recovery of Qt from OP waste using rationally designed molecularly imprinted polymer (MIP). Density Functional Theory (DFT) was used for the theoretical selection of the best conformer of Qt (template), methacrylic acid (MAA) as functional monomer, ratio of Qt-MAA for getting stable pre-polymerization complex, and to avoid hit and trial experiments. The theoretical results were validated experimentally by synthesizing MIP/ control polymer (NIP) using MAA as functional monomer, EGDMA as a cross-linker and AIBN as initiator. Synthesized MIP/NIP were characterized using various characterization techniques to confirm successful imprinting. Prepared MIP and NIP could effectively rebind the Qt molecule with binding capacity of 46.67 and 20.89 mg g-1 respectively. Furthermore, synthesized MIP could selectively recover 62.81 % of Qt from 1 g of dry onion peel powder. This study can be effectually used for sustainable recovery of Qt in large scale for various foods, cosmetic and pharmaceutical applications.

Effects of different preparation and cooking processes on the bioactive molecules of Allium vegetables.

Allium species are among the most widely cultivated vegetables for centuries for their positive effects on human health and their variety of uses in food preparation and cooking. Preparation and cooking processes create chemical changes that can affect the concentration and bioavailability of bioactive molecules. Understanding the changes in bioactive compounds and bioactive activities in Allium vegetables resulting from preparation and cooking processes is essential for better retention of these compounds and better utilization of their health benefits. This study aimed to investigate the effects of different preparation and cooking processes on the bioactive molecules of Allium vegetables. This review concludes that bioactive compounds in Allium vegetables are affected by each preparation and cooking process depending on variables including method, time, temperature. Owing to differences in the matrix and structure of the plant, preparation and cooking processes show different results on bioactive compounds and bioactive activities for different vegetables. Continued research is needed to help fill gaps in current knowledge, such as the optimal preparation and cooking processes for each Allium vegetable.

Characterization of flavor volatiles in raw and cooked pigmented onion (Allium cepa L) bulbs: A comparative HS-GC-IMS fingerprinting study.

Variations in volatile flavor components in pigmented onion bulbs (purple, white, and yellow) before and after cooking were characterized by headspace gas chromatography-ion migration spectrometry (HS-GC-IMS) to investigate their odor traits. Results showed that 39 and 45 volatile flavor compounds were identified from pigmented onion bulbs before and after cooking via the HS-GC-IMS fingerprinting, respectively. Sulfurs (accounting for 50.65%-63.42%), aldehydes (13.36%-22.11%), and alcohols (11.32%-17.94%) ranked the top three prevailing compound categories in all pigmented onions (both raw and cooked). Compared to the raw colored onion bulbs, the relative proportion of sulfurs in cooked onions decreased, whereas the relative proportion of alcohols, esters, pyrazines, and furans increased. Two reliable prediction models were established through orthogonal partial least squares-discriminant analysis (OPLS-DA), and 8 and 22 distinctive odor compounds were sieved out by variable importance in projection (VIP>1.0) as volatile labels, respectively. Both principal component analysis (PCA) and clustering heatmap exhibited favorable distinguishing effects for various pigmented onion bulbs before and after cooking. These results might offer insights into understanding the odor characteristics of different pigmented onions.

First Report of Erwinia aphidicola Causing Bulb Rot of Onion in Chile.

During the 2021-22 and 2022-23 seasons (December to February), onion plants (Allium cepa L.) showing decay, leaf blight, chlorosis and water soak lesions were collected in Central Chile. Five symptomatic plants were sampled from 20 different onion fields. Brown rot of the external scales was observed in bulbs from two fields: one planted with the cv. Campero (20 ha; O'Higgins Region), and another with cv. Marenge (2 ha; Metropolitan Region). The disease incidence in these fields ranged from 2% to 5%. Isolations were carried out from symptomatic leaves and bulbs from these fields on King's B medium, resulting in small white colonies with smooth margin. Three isolates were selected, two from first field (QCJ3A & QCJ2B), and one from second field (EPB1). A preliminary identification based on 16S rRNA sequences was conducted. BLAST analyses of strains QCJ3A, QCJ2B and EPB1 (GenBank Accession No. PP345601 to PP345603) against the NCBI Database resulted in a match with strains (GenBank Accession No. ON255770.1 and ON255825.1) isolated from infected bulbs in Texas, USA identified as Erwinia spp. (Khanal et al. 2023), with 100% coverage and 100% identity (707 bp out of 707). To evaluate the pathogenicity of these three strains, onion bulbs were inoculated (Guajardo et al. 2023). Toothpicks previously immersed in a bacterial suspension at ~ 108 colony forming units (CFU)/mL were pricked at a 4 cm depth into the shoulders of onion bulbs bought from commercial store and incubated at room temperature. Bulbs inoculated with sterile water served as negative control. A known onion bulb rotting bacterial strain of Dickeya sp. was used as a positive control. At the end of the incubation period (20 days), bulbs were opened longitudinally across their inoculation site, showing that the external scales had a brown color. Negative control remained asymptomatic. Strains were re-isolated from damaged tissue and identified as Erwinia sp. This assay was repeated three times with the same results. For further identification, genomic DNA extraction was carried out using the Blood & Cell Culture DNA Kit (Qiagen), and genome sequencing was performed in the Illumina HiSeq 2500 platform. The Whole Genome Shotgun project for strains QCJ3A, QCJ2B and EPB1 have been deposited at DDBJ/ENA/GenBank under the accession JBANEI010000000, JBANEJ010000000 and JBANEK010000000. The average nucleotide identity (ANI) values were 99.6% (EPB1), 98.2% (QCJ2B), and 99.6% (QCJ3A) and DNA-DNA hybridization (dDDH) values were 96.9% (EPB1), 83.7% (QCJ2B), and 97.1% (QCJ3A), when compared with the type strain Erwinia aphidicola JCM 21238 (GenBank accession No. GCF_014773485.1). The three strains were deposited in the Chilean Collection of Microbial Genetic Resources (CChRGM). Erwinia aphidicola has been previously described causing diseases in common bean (Phaseolus vulgaris) and pea (Pisum sativum), in Spain (Santos et al. 2009) and in pepper (Capsicum annuum) in China (Luo et al. 2018). Its close relative E. persicina has been reported causing bulb rot in onion in Korea (Cho et al. 2019) and garlic in Europe (Galvez et al. 2015). To our knowledge, this is the first report of E. aphidicola causing a bulb rot of onion in Chile. Although the distribution and prevalence of this bacterium in Chilean agroecosystems is not known, it can be a potential cause of losses in onions and other crops such as beans, peas, and peppers. Additional studies should be conducted to determine the host range of Chilean Erwinia aphidicola strains.

OnionFoliageSET: Labeled dataset for small onion and foliage flower crop detection.

Digital image datasets for Precision Agriculture (PA) still need to be available. Many problems in this field of science have been studied to find solutions, such as detecting weeds, counting fruits and trees, and detecting diseases and pests, among others. One of the main fields of research in PA is detecting different crop types with aerial images. Crop detection is vital in PA to establish crop inventories, planting areas, and crop yields and to have information available for food markets and public entities that provide technical help to small farmers. This work proposes public access to a digital image dataset for detecting green onion and foliage flower crops located in the rural area of Medellín City - Colombia. This dataset consists of 245 images with their respective labels: green onion (Allium fistulosum), foliage flowers (Solidago Canadensis and Aster divaricatus), and non-crop areas prepared for planting. A total of 4315 instances were obtained, which were divided into subsets for training, validation, and testing. The classes in the images were labeled with the polygon method, which allows training machine learning algorithms for detection using bounding boxes or segmentation in the COCO format.

PEDOT-Doped Mesoporous Nanocarbon Electrodes for High Capacitive Aqueous Symmetric Supercapacitors.

Poly(3,4-ethylenedioxythiophene) (PEDOT) and PEDOT-functionalized carbon nanoparticles (f-CNPs) were synthesized by in situ chemical oxidative polymerization and pyrolysis methods. f-CNP-PEDOT nanocomposites were prepared by varying the concentration of PEDOT from 1 to 20% by weight (i.e., 1, 2.5, 5, 10, and 20 wt%). Several characterization techniques, such as field-emission scanning electron microscopy (FESEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), N2 Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) analyses, as well as cyclic voltammetry (CV), galvanostatic charge discharge (GCD), and electrochemical impedance spectroscopy (EIS), were applied to investigate the morphology, the crystalline structure, the N2 adsorption/desorption capability, as well as the electrochemical properties of these new synthesized nanocomposite materials. FESEM analysis showed that these nanocomposites have defined porous structures, and BET surface area analysis showed that the standalone f-CNP exhibited the largest surface area of 801.6 m2/g, whereas the f-CNP-PEDOT with 20 wt% exhibited the smallest surface area of 116 m2/g. The BJH method showed that the nanocomposites were predominantly mesoporous. CV, GCD, and EIS measurements showed that f-CNP functionalized with 5 wt% PEDOT had a higher capacitive performance compared to the individual f-CNPs and PEDOT constituents, exhibiting an extraordinary specific capacitance of 258.7 F/g, at a current density of 0.25 A/g, due to the combined advantage of enhanced electrochemical activity induced by PEDOT doping, and highly developed porosity of f-CNPs. Symmetric aqueous supercapacitor devices were fabricated using the optimized f-CNP-PEDOT doped with 5 wt% of PEDOT as active material, exhibiting a high capacitance of 96.7 F/g at 1.4 V, holding practically their full charge, after 10,000 charge-discharge cycles at 2 A/g, thus providing the highest electrical electrodes performance. Hereafter, this work paves the way for the potential use of f-CNP-PEDOT nanocomposites in the development of high-energy-density supercapacitors.

Poly-vinyl-pyrrolidone capped luminescent zinc oxide nanocomposites as excellent tools for germicidal and photo-catalytic performances.

Alternate antibiotics developed through the involvement of nanomaterials are gaining interest due to their economical and lower toxicity concerns. A newly developed biopolymer-based polyvinylpyrrolidone/zinc oxide (PVP/ZnO) nanocomposite (NCs) was efficiently synthesized by an environment-friendly approach, utilizing onion and garlic peel extract as a bio-surfactant, zinc acetate as the source, PVP as the stabilizing agent, and sodium hydroxide as the precipitant. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) investigations verified the crystalline properties of ZnO, PVP, and PVP/ZnO-based NCs. The structure of the biopolymer-linked ZnO particles interpolated inside the PVP array was seen to have a layered and flaky structure, as validated by field emission scanning electron microscopy (FE-SEM) analysis, which revealed its occurrence in the nanometer range. The XRD examination verified that the surface topographical image of PVP/ZnO NCs had an average thickness of 21 nm. The PVP/ZnO nanocrystals demonstrated exceptional photocatalytic efficacy, with a breakdown rate of 88% and almost 92% for the methylene blue dye. Therefore, the PVP/ZnO matrix exhibits superior antibacterial activity compared to other extracts, resulting in greater microbial suppression. The results above indicate that the ZnO-intercalated PVP array has a stronger reinforcing effect than other components. Hence, PVP/ZnO nanocrystals exhibit enormous potential as a favorable substance for environmental and biomedical intentions.

Innovative chitosan-onion polysaccharide composite films: A study on the preservation effects on cherry tomatoes.

Natural preservation materials have long been a focus of research in the quality control of fruits and vegetables. This study aimed to develop composite films with exceptional preservation properties by utilizing chitosan (CS) as the film-forming material and incorporating onion polysaccharide (ONP) as the active component. The CS-ONP composite films were prepared, and their performance and preservation effects were evaluated. The results demonstrated that increasing the ONP content significantly enhanced the shading, antimicrobial, and antioxidant capabilities of the CS-ONP composite films. Preservation experiments revealed that the CS-ONP composite films effectively delayed the quality decline of cherry tomatoes during storage. However, despite the improvements brought by ONP, certain drawbacks persisted, such as reduced mechanical properties and alterations in surface structure. In summary, the CS-ONP composite films exhibit promising potential as novel materials for fruit and vegetable preservation. PRACTICAL APPLICATION: The spoilage of fruits and vegetables can cause huge economic losses. This study addresses this challenge by using chitosan as the film-forming substrate and adding crude onion polysaccharide as the active ingredient to create composite films. The preservation effects of these films on cherry tomatoes were studied. Although only cherry tomatoes were tested in this study, the composite films demonstrated significant potential for broader applications in fruit and vegetable preservation.

Onion husk-derived high surface area graphene-like carbon for supercapacitor electrode material application.

In this study, we report the synthesis of graphene-like carbon derived from onion husk, with potential application as an electrode material in energy storage devices. Graphene-like carbon (GLC) was synthesized from onion husk (OH) by preliminary carbonization at 550 °C, followed by thermochemical activation at various temperatures to determine the optimal activation parameters. The surface morphology of graphene-like carbon from onion husk (GLC-OH) samples after carbonization shows distinct thermal exfoliation of the material. This layering upon activation in KOH promotes the formation of highly porous graphene-like carbon flakes. According to the Brunauer-Emmett-Teller (BET) method, the specific surface area at 850 °C was 1924 m2/g. The X-ray diffraction (XRD) and Raman spectroscopy results reveal the emergence of few-layer graphene with a significant amount of structural defects at 850 °C. As the temperature increases, the formation shifts towards multilayer graphene, which leads to a decrease in the specific surface area of the carbon material. The electrochemical characterization of the assembled GLC-OH-based supercapacitor synthesized at 850 °C revealed a markedly higher specific capacitance value of 131 F/g, along with a Coulombic efficiency of 98 % at a gravimetric current density of 1 A/g. Additionally, it exhibited a low charge transfer resistance (RCT) of approximately 1.4 Ω. Our study investigates the influence of structural changes on the electrochemical performance of biomass-derived activated carbon, highlighting the potential of graphene-like carbon from onion husk as a promising and low-cost material for future energy storage devices.