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  • o-Aminophenol derivatives are of particular interest for their di-verse biological activities and potential therapeutic applications. Such as, antioxidant, an-tibacterial, and cytotoxic activities.

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  • Persimmon fruit is highly susceptible to chilling injury (CI) during cold storage. Notably, glycine betaine (GB), a compound that helps regulate cell osmotic balance, can alleviate postharvest CI in various fruits. In this study, the postharvest application of GB increased chilling tolerance, delayed CI, and reduced the CI index in 'Youhou' sweet persimmon fruit during cold storage. Moreover, GB treatment markedly decreased the O · production rate and malondialdehyde (MDA) and HO content while significantly increasing the ascorbic amounts of acid and glutathione (GSH). Compared with the control group, GB treatment increased activities of antioxidant enzymes such as glutathione reductase (GR), glutathione peroxidase (GPX), ascorbate peroxidase (APX), catalase (CAT), and superoxide dismutase (SOD). GB treatment also reduced the activities of phenylalanine ammonia-lyase, polyphenol oxidase, and peroxidase. RNA sequencing revealed that GB treatment significantly altered gene expression linked to sugar metabolism, GSH metabolism, and phenylpropanoid biosynthesis. This study provides novel insights into the regulatory mechanisms of GB treatment alleviating CI in postharvest persimmon fruit. PRACTICAL APPLICATION: 'Youhou' sweet persimmons are prone to rapid softening after harvest. This softening process can be limited through cold storage; this can also result in chilling injury (CI). The research findings suggest that glycine betaine (GB) treatment delays 'Youhou' persimmon fruit softening and alleviates CI during cold storage. GB application could be a feasible technique for extending the storage life of 'Youhou' sweet persimmon fruit.

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  • Prunus mandshurica (Maxim.) Koehne pulp and almonds are rich in nutrients and bioactive compounds; however, their chemical composition and content remain unexplored. We systematically evaluated their physicochemical properties and antioxidant capacities using 14 clones. Significant differences in physicochemical properties observed between the tested clones provided opportunities for developing and utilizing germplasm resources. Clones with thicker pulps exhibited sweet flavors, heavier fruits, lighter almonds, and lower kernel rates. Their pulp was relatively low in total sugar (1.66 - 14.91%) and soluble solids content (6.23 - 18.67°Brix) but rich in titratable acidity (2.81 - 4.20%) and vitamin C (0.97 - 1.65 mg/g), making them a promising option for food and nutraceutical applications. Almond oil was the main component (50.02%), followed by protein (25.82%), and amygdalin (3.17%), with high balanced amino acid levels. Nine clones with amygdalin content > 3% indicated a high medicinal value. The fruit was rich in total phenolics, total flavonoids, and antioxidant capacity, and its pulp exhibited a stronger antioxidant capacity than that of almonds. Clones 783 and 717 had sweet and thick pulp with high nutrient content and antioxidant capacity, whereas clone 772 pulp exhibited a strong antioxidant capacity and a high yield, making it a good source of natural antioxidants. We are the first to assess the physicochemical properties and antioxidant capacity of 14 P. mandshurica clones fruit to explore their potential applications in the food and pharmaceutical industries, and provide data to support the selection of excellent germplasm for different needs.

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  • Under changing climates, engineering drought-resistant crops is critical for reducing food insecurity. Here, we leverage plant "stress memory" and ROS-generating silica nanoparticles (NPs) to enhance the drought tolerance of cucumber plants. Under PEG-mimicking drought conditions, cucumber seeds primed with fumed silica NPs (40 mg/L, 4 h) exhibited an increased seed germination rate (from 66.7 to 80.0%), enhanced seedling vigor (59.3%), and improved root and shoot length (24.4 and 74.1%, respectively) compared to seeds primed with water. In contrast, silicic acid and traditional silicon fertilizers at the same dose did not show priming effects, indicating that the released Si did not contribute to the observed outcomes. Metabolomics reveals that silica seed priming accelerated the mobilization of seed-stored reserves. Vegetative tissues also exhibit enhanced drought resistance, and metabolomics analysis reveals that the drought resistance strategy involves the upregulation of sugars (glucose, sucrose, trehalose, maltose; 34.7-74.8%), amino acids (methionine, 6-fold), signaling molecules (salicylic acid, 2.5-fold), and antioxidants (ascorbic acid, 2-hydroxycinnamic acid, ferulic acid, P-coumaric acid; 16.0-83.8%). Transcriptomics analysis reveals that several drought- and even desiccation-tolerant associated genes exert more pronounced transcript changes in silica-primed leaves. The life cycle study shows that silica seed priming does not generate any yield penalty or compromise the nutritional quality of the fruits. Importantly, offspring seeds exhibit enhanced vigor and drought tolerance, indicating the transgenerational transmission of the acquired drought resilience. The findings of this study provide a promising approach for engineering crops that are resilient to climate change.

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  • Melatonin is known to delay postharvest nutrient loss. However, its specific roles in regulating cell wall and sugar metabolism to maintain postharvest quality in flowering Chinese cabbage remain unclear. In this study, postharvest flowering Chinese cabbage was treated with melatonin (100 µmol L) to investigate the cell wall and sugar metabolisms. Our research found that melatonin supplementation increased levels of important nutrients like ascorbic acid, sugars, soluble protein, carotenoid, and glucosinolates. It also enhanced various cell wall components (cellulose, hemicellulose, lignin, and protopectin) while reducing water-soluble pectin accumulation. Melatonin helped stabilize cell wall by reducing the expression of genes related to cell wall degradation (BrBGAL4, BrPG, BrCEL3, and BrPME3), inhibiting activities of cell wall-degrading enzymes like pectin methylesterase and cellulase, and improving expressions of cellulose biosynthesis-related genes (BrCesA1, BrCesA3.1, and BrCesA3.2). Additionally, it boosted sugar accumulation by increasing activities of sucrose synthetase and sucrose phosphate synthetase, upregulating expressions of BrSUS1, BrSUS5, BrSPS1F, BrSPS3F, BrSPS4F, and suppressing activities of neutral invertase and acidic invertase and expressions of genes involved in sugar metabolism (BrSUS3, BrINV, BrSWEET2, BrSWEET4, and BrSWEET17). This study highlights melatonin's vital roles in maintaining postharvest quality and offers practical insights for improving market performance of flowering Chinese cabbage.

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  • The investigation of biomolecules is essential due to abnormalities in biological metabolism in the human body. Dopamine (DA) and uric acid (UA) are important chemicals that coexist in biological systems and play crucial roles in various physiological processes related to human metabolism. This study explores the application of carbon and SnO nanoparticles for DA and UA sensing, focusing on the preparation of Sn/SnO nanocomposites through electrospinning and plasma treatment. The research aims to measure these concentrations quickly and accurately, offering advantages such as low manufacturing costs and environmental friendliness.

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  • This meta-analysis systematically investigates the markers of oxidative stress (OS) and antioxidant systems in the saliva and serum of patients with oral submucous fibrosis (OSF) and healthy controls.

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  • Modelling oxidative potential of atmospheric particle: A 2-year study over France.

    The oxidative potential (OP) of particulate matter (PM) has emerged as a promising indicator of the adverse effects of PM on human health. In particular, OP is an indicator for oxidative stress in biological media through formation of reactive oxygen species. To provide a mapping of the spatial and temporal OP variability over France, we have developed a strategy to simulate the volume-normalized oxidative potential (OP) in the state-of-the-art CHIMERE air quality model over the metropolitan French territory for the years 2013 and 2014. To do so, we combined a measurement-derived and source specific intrinsic OP (OP) receptor modelling approach with Particle Source Apportionment Technology (PSAT) in CHIMERE. First, the model's ability to reproduce PM concentrations and speciation was verified using in situ observations in mainland France. Furthermore, a mostly satisfying correspondence between receptor model and PSAT outputs was obtained considering their source specific chemical profiles. Simulated versus observed OP values showed median correlations ranging from 0.35 to 0.60 and mean fractional biases from -30 % to zero, depending on the OP assay considered (ascorbic acid AA, or dithiothreitol DTT) and the PM sources taken into account (i.e. two methods with different PM sources have been used, the reduced and the extended set methods). The modelled two-year average OP fields show greater spatial hot spots over large urban areas (especially along roadsides) compared to those for PM distributions, due to elevated intrinsic OP values for the primary anthropogenic sources such as traffic and biomass burning. These effects are stronger for the AA compared to the DTT assays, and for a method with a reduced set compared to an extended set of sources. Overall, through the OP apportionment, these results advocate for reinforcing action plans to reduce emissions from road traffic as well as biomass burning emissions.

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  • The chain conformation of conjugated oligomers are critical for constructing ultrafine fluorescent nanoprobes with outstanding sensing performances owing to their suitable molecular flexibility and fine-tuned aggregation state. Herein, a series of pyrenyl-pyridine oligomers (OPPs) were designed and conveniently prepared by one-pot Sonogashira coupling of flexible 2,6-bis(ethynyl)pyridine with different rigid pyrene unit. Novel fluorescent nanoprobes (OPPNPs, ca. 2.50-25.4 nm in diameter) were hence readily fabricated through a microemulsion route, showcasing significantly distinct detecting properties due to their distinctive chain conformations. In particular, ultrasmall OPP1NPs (~ 3.75 nm) bearing zig-zag-shaped 1,6-substituted pyrenyl-pyridyl conjugated chain presented superior π-π stacking, strong excimer emission and best sensing performances for Fe via electron transfer (ET) and OPP1NPs aggregation-based fluorescence quenching. Additionally, ascorbic acid (AA) could act as an effective reducer and chelator, resulting in the fluorescence recovery of OPP1NPs. Under the optimal conditions, ultralow detection limits of OPP1NPs for Fe (LOD, 0.06 nM, S/N = 3) and AA (LOD, 8 nM) were achieved. Furthermore, small and biocompatible OPP1NPs enabled efficient fluorescence imaging of Fe and AA in live cells. Moreover, the conformation-regulated sensing strategy and ET mechanism are also supported by DFT calculations.

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  • Biosynthesis techniques for nanomaterials have advanced significantly, promoting eco-friendly synthesis chemistry as a sustainable alternative to conventional methods. This study presents a novel and environmentally friendly approach for synthesizing nanoparticulate ZnO, CuO, and ZnO/CuO nanocomposites using aqueous extracts of Pleurotus ostreatus spent substrate, is reported. The structural, optical, and morphological properties of the synthesized NPs were analysed. A hexagonal phase of ZnO NPs and a monoclinic phase of CuO NPs were obtained according to the X-ray diffraction analysis. A reduction in the peak intensity of these metal oxides was observed in the ZnO/CuO NPs due to reduced crystallinity. The absorption spectra, obtained from the UV-vis analysis, showed peaks at 354, 365, and 525 nm for the ZnO, CuO, and ZnO/CuO NPs, respectively. An anticancer assay of the NPs was conducted using human embryonic kidney (HEK 293) and cervical carcinoma (HeLa) cell lines, while a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was used for the antioxidant evaluation. The ZnO, CuO, and ZnO/CuO NPs showed higher antioxidant potency with IC of 2.15, 2.16, and 3.18 µg/mL, respectively, than the ascorbic acid (4.25 µg/mL). This indicates that the nanoparticles were more effective in capturing DPPH free radicals. Anticancer assays showed strong cytotoxic effects for all nanoparticles, with ZnO NPs exhibiting the highest activity (IC: 1.94 μM for HEK 293 cells, 3.23 μM for HeLa cells), surpassing CuO and ZnO/CuO NPs. Cell viability for both HEK 293 and HeLa cells decreased as nanoparticle concentration increased, confirming dose-dependent cytotoxicity. The green synthesized metal oxides and their composite have the potential for biomedical applications.

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