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1.
Foods ; 13(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38998629

RESUMO

By employing headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), this study displayed the compositional changes in volatile organic compounds (VOCs) in Tricholoma matsutake samples subjected to hot-air drying (HAD) and vacuum freeze-drying (VFD) processes from their fresh samples. A total of 99 VOCs were detected, including 2 acids, 10 aldehydes, 10 alcohols, 13 esters, 12 ketones, 24 alkanes, 14 olefins, 7 aromatic hydrocarbons, and 7 heterocyclic compounds. Notably, the drying process led to a decrease in most alcohols and aldehydes, but an increase in esters, ketones, acids, alkanes, olefins, aromatic, and heterocyclic compounds. Venn diagram (Venn), principal component analysis (PCA), and partial least squares-discriminant analysis (PLS-DA) analyses enabled an easy and rapid distinction between the VOC profiles of T. matsutake subjected to different drying methods. Among the identified VOCs, 30 were designated as marker VOCs indicative of the employed drying process. And the VFD method was more capable of preserving the VOCs of fresh T. matsutake samples than the HAD method. Benzaldehyde, 1-Octen-3-ol, 3-Octanol, and (E)-2-Octen-1-ol were identified as markers for FRESH T. matsutake. Conversely, (E)-3-Hexene, lavender lactone, and α-Pinene were associated with VFD T. matsutake. For HAD T. matsutake, olefins, pyrazine, and esters, particularly ocimene, 2,5-Dimethyl-pyrazine, and methyl cinnamate, significantly contributed to its particularities. The results from this present study can provide a practical guidance for the quality and flavor control of volatile organic compounds in preciously fungal fruiting bodies by using drying processes.

2.
Plants (Basel) ; 13(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999618

RESUMO

Crop production in Afghanistan suffers from limited phosphorus (P) availability, which severely hinders national agriculture sustainability. This study hypothesized that deep fertilizer placement could significantly enhance the uptake of immobile P and, thus, tissue P accumulation and crop yield. A two-year pot experiment growing two maize (Zea mays) hybrid cultivars (Xida-789 and Xida-211) was, therefore, conducted to test these hypotheses under three contrasting fertilizer placement methods (broadcast, side band, and deep band). In doing so, P concentrations in both maize tissues and soils were compared at 45, 60, and 115 days after sowing (DAS) under nine combinations of nitrogen (N) and P fertilizer rates (kg ha-1: N112P45, N112P60, N112P75, N150P45, N150P60, N150P75, N187P45, N187P60, N187P75). Results have shown that deep band placement significantly increased P uptake efficiency, leading to greater P concentration and accumulation in maize tissues compared to the other two fertilization methods. This improved P uptake was attributed to several factors associated with deep placement, including reduced P fixation, enhanced root access to P, and moisture availability for P uptake. Additionally, deep band placement combined with higher N application rates (N187 and N150) further enhanced plant P uptake by promoting P availability and utilization mechanisms. Deep band placement also resulted in significantly higher total soil P, Olsen-P, and P use efficiency than broadcast and side band methods, indicating a more efficient P fertilization strategy for maize that can improve growth and yield. This study also found positive correlations between P concentration in plant organs and soil Olsen-P, highlighting the importance of adequate soil P levels for optimal plant growth. Overall, our results have shown that deep band fertilizer placement emerged as a superior strategy for enhancing P uptake efficiency, utilization, and maize productivity compared to broadcast and side band placement. The outcome generated from the deep band fertilization by this greenhouse study can be recommended for field practices to optimize P fertilizer use and improve maize production while minimizing potential environmental P losses associated with broadcast fertilization.

3.
Chemosphere ; 361: 142522, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838869

RESUMO

Selecting safe, non-toxic, and non-metallic semiconductor materials that facilitate the degradation of pollutants in water stands out as an optimal approach to combat environmental pollution. Herein, graphitic carbon nitride (g-C3N4)-based hollow nanospheres nonmetallic photocatalyst modified with covalent organic framework materials named TpMA, based on 1, 3, 5-trimethylchloroglucuronide (Tp) and melamine (MA), was successfully synthesized (abbreviated as CNTP). The ordered electron donor-acceptor structure inherent in TpMA contributed to enhancing the transport efficiency of photogenerated carriers in CNTP. The CNTP photocatalysts exhibited excellent performance in degrading rhodamine B and tetracycline in visible light, with optimal degradation rates reached more than 90% in 60 and 80 min, respectively, which were 5.3 and 3.0 times higher than those of pure CNNS. The increased photocatalytic efficiency observed in CNTP composites could be traced back to the covalently connection between the two molecules, forming a π-conjugated system that facilitated the separative efficiency of photogenerated electron-hole pairs and intensified the utilization of visible light. This study provided a new means to design and fabricate highly efficient and environmentally friendly non-metallic photocatalytic materials.


Assuntos
Grafite , Nanosferas , Compostos de Nitrogênio , Rodaminas , Triazinas , Poluentes Químicos da Água , Nanosferas/química , Catálise , Triazinas/química , Grafite/química , Rodaminas/química , Compostos de Nitrogênio/química , Poluentes Químicos da Água/química , Luz , Tetraciclina/química , Nitrilas/química , Processos Fotoquímicos , Fotólise
4.
J Med Chem ; 67(13): 11435-11449, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38889119

RESUMO

Enhancing the selectivity of alpha2-adrenoceptor (α2A-AR) agonists remains an unresolved issue. Herein, we reported the design of an α2A-AR agonist using the conformation constraint method, beginning with medetomidine. The structure-activity relationship indicated that the 8-substituent of chromane derivatives exerted the most pronounced effect on α2A-AR agonistic activity. Compounds A9 and B9 were identified as the most promising, exhibiting EC50 values of 0.78 and 0.23 nM, respectively. Their selectivity indexes surpassed dexmedetomidine (DMED) by 10-80 fold. In vivo studies demonstrated that both A9 and B9 dose-dependently increased the loss of righting reflex in mice, with ED50 values of 1.54 and 0.138 mg/kg, respectively. Binding mode calculations and mutation studies suggested the indispensability of the hydrogen bond between ASP1283.32 and α2A-AR agonist. In particular, A9 and B9 showed no dual reverse pharmacological effect, a characteristic exhibited by DMED in α2A-AR activation.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2 , Cromanos , Desenho de Fármacos , Receptores Adrenérgicos alfa 2 , Animais , Receptores Adrenérgicos alfa 2/metabolismo , Cromanos/farmacologia , Cromanos/química , Cromanos/síntese química , Relação Estrutura-Atividade , Camundongos , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Agonistas de Receptores Adrenérgicos alfa 2/química , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Masculino
5.
Front Microbiol ; 15: 1367184, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827150

RESUMO

Diversifying cultivation management, including different crop rotation patterns and soil amendment, are effective strategies for alleviating the obstacles of continuous cropping in peanut (Arachis hypogaea L.). However, the peanut yield enhancement effect and temporal changes in soil chemical properties and microbial activities in response to differential multi-year crop rotation patterns and soil amendment remain unclear. In the present study, a multi-year localization experiment with the consecutive application of five different cultivation managements (including rotation with different crops under the presence or absence of external quicklime as soil amendment) was conducted to investigate the dynamic changes in peanut nutrient uptake and yield status, soil chemical property, microbial community composition and function. Peanut continuous cropping led to a reduction in peanut yield, while green manure-peanut rotation and wheat-maize-peanut rotation increased peanut yield by 40.59 and 81.95%, respectively. A combination of quicklime application increased yield by a further 28.76 and 24.34%. Alterations in cultivation management also strongly affected the soil pH, nutrient content, and composition and function of the microbial community. The fungal community was more sensitive than the bacterial community to cultivation pattern shift. Variation in bacterial community was mainly attributed to soil organic carbon, pH and calcium content, while variation in fungal community was more closely related to soil phosphorus content. Wheat-maize-peanut rotation combined with quicklime application effectively modifies the soil acidification environment, improves the soil fertility, reshapes the composition of beneficial and harmful microbial communities, thereby improving soil health, promoting peanut development, and alleviating peanut continuous cropping obstacles. We concluded that wheat-maize-peanut rotation in combination with quicklime application was the effective practice to improve the soil fertility and change the composition of potentially beneficial and pathogenic microbial communities in the soil, which is strongly beneficial for building a healthy soil micro-ecology, promoting the growth and development of peanut, and reducing the harm caused by continuous cropping obstacles to peanut.

6.
Microbiol Spectr ; : e0416523, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916324

RESUMO

Soil microorganisms are the most active participants in terrestrial ecosystems, and have key roles in biogeochemical cycles and ecosystem functions. Despite the extensive research on soil pH as a key predictor of microbial community and composition, a limitation of these studies lies in determining whether bacterial and/or fungal communities are directly or indirectly influenced by pH. We conducted a controlled laboratory experiment to investigate the effects of soil pH amendment (+/- 1-2 units) with six levels on soil microbial communities in two contrasting Chinese agricultural soils (pH 8.43 in Dezhou, located in the North China Plain, Shandong vs pH 6.17 in Wuxi, located in the Taihu Lake region, Jiangsu, east China). Results showed that the fungal diversity and composition were related to soil pH, but the effects were much lower than the effects of soil pH on bacterial community in two soils. The diversity and composition of bacterial communities were more closely associated with soil pH in Wuxi soils compared to Dezhou soils. The alpha diversity of bacterial communities peaked near in situ pH levels in both soils, displaying a quadratic fitting pattern. Redundancy analysis and variation partition analysis indicated that soil pH affected bacterial community and composition by directly imposing a physiological constraint on soil bacteria and indirectly altering soil characteristics (e.g., nutrient availability). The study also examined complete curves of taxa relative abundances at the phylum and family levels in response to soil pH, with most relationships conforming to a quadratic fitting pattern, indicating soil pH is a reliable predictor. Furthermore, soil pH amendment affected the transformation of nitrogen and the abundances of functional genes involved in the nitrogen cycle, and methane production and consumption. Overall, results from this study would enhance our comprehension of how soil microorganisms in contrasting farmlands will respond to soil pH changes, and would contribute to more effective soil management and conservation strategies. IMPORTANCE: This study delves into the impact of soil pH on microbial communities, investigating whether pH directly or indirectly influences bacterial and fungal communities. The research involved two contrasting soils subjected to a 1-2 pH unit amendment. Results indicate bacterial community composition was shaped by soil pH through physiological constraints and nutrient limitations. We found that most taxa relative abundances at the phylum and family levels responded to pH with a quadratic fitting pattern, indicating that soil pH is a reliable predictor. Additionally, soil pH was found to significantly influence the predicted abundance of functional genes involved in the nitrogen cycle as well as in methane production and consumption processes. These insights can contribute to develop more effective soil management and conservation strategies.

7.
Environ Sci Pollut Res Int ; 31(25): 37705-37716, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38780846

RESUMO

The hydrographic and environmental factors along the Three Gorges Reservoir (TGR) have been significantly altered since the Three Gorges Dam (TGD) began working in 2006. Here, we collected 54 water samples, and then measured the environmental factors, followed by sequencing of the 18S rRNA gene and subsequent analysis of community assembly mechanisms. The findings indicated that the majority of environmental variables (such as AN, TP, Chl-a, CODMn, and Cu) exhibited both temporal and spatial variations due to the influences of the TGD. The distribution of different environmental factors and microeukaryotic plankton communities is influenced by the changing seasons. The community structure in TGR showed variations across three seasons, possibly due to variations in their environmental preferences, inherent dissimilarities, and seasonal succession. Furthermore, different communities exhibited a comparable distance-decay trend, suggesting that distinct taxa are likely to exhibit a similar spatial distribution. In addition, the community formation in TGR was influenced by both deterministic and stochastic factors, with the balance between them being mainly controlled by the season. Specifically, deterministic processes could explain 33.9-51.1% of community variations, while stochastic processes could contribute 23.5-32.2%. The findings of this research demonstrated that the varying ecological processes' significance relied on environmental gradients, geographical scale, and ecological conditions. This could offer a fresh outlook on comprehending the composition, assembly mechanisms, and distribution patterns of microeukaryotic plankton in reservoir ecosystems.


Assuntos
Plâncton , Estações do Ano , China , Monitoramento Ambiental , RNA Ribossômico 18S
8.
Sci Total Environ ; 937: 173309, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38782268

RESUMO

The grass family (Poaceae) dominates ~43 % of Earth's land area and contributes 33 % of terrestrial primary productivity that is critical to naturally regulating atmosphere CO2 concentration and global climate change. Currently grasses comprise ~11,780 species and ~50 % of them (~6000 species) utilize C4 photosynthetic pathway. Generally, grass species have smaller leaves under colder and drier environments, but it is unclear whether the primary drivers of leaf size differ between C3 and C4 grasses on a global scale. Here, we analyzed 34 environmental variables, such as latitude, elevation, mean annual temperature, mean annual precipitation, and solar radiation etc., through a comparatively comprehensive database of ~3.0 million occurrence records from 1380 C3 and 978 C4 grass species (2358 species in total). Results from this study confirm that C4 grasses have occupied habitats with lower latitudes and elevations, characterized by warmer, sunnier, drier and less fertile environmental conditions. Grass leaf size correlates positively with mean annual temperature and precipitation as expected. Our results also demonstrate that the mean temperature of the wettest quarter of the year is the primary control for C3 leaf size, whereas C4 leaf size is negatively correlated with the difference between summer and winter temperatures. For C4 grasses, phylogeny exerts a significant effect on leaf size but is less important than environmental factors. Our findings highlight the importance of evolutionarily contrasting variations in leaf size between C3 and C4 grasses for shaping their geographical distribution and habitat suitability at the global scale.


Assuntos
Ecossistema , Folhas de Planta , Poaceae , Poaceae/anatomia & histologia , Folhas de Planta/anatomia & histologia , Fotossíntese , Mudança Climática
9.
Plants (Basel) ; 13(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38592790

RESUMO

Soil compaction is one of the crucial factors that restrains the root respiration, energy metabolism and growth of peanut (Arachis hypogaea L.) due to hypoxia, which can be alleviated by ventilation. We therefore carried out a pot experiment with three treatments: no ventilation control (CK), (2) ventilation volumes at 1.2 (T1), and 1.5 (T2) times of the standard ventilation volume (2.02 L/pot). Compared to no-ventilation in compacted soil, ventilation T1 significantly increased total root length, root surface area, root volume and tips at the peanut anthesis stage (62 days after sowing), while T2 showed a negative impact on the above-mentioned root morphological characteristics. At the podding stage (S2, 95 days after sowing), both ventilation treatments improved root morphology, especially under T1. Compared to CK, both ventilation T1 and T2 decreased the activities of enzymes involving the anaerobic respiration, including root lactate dehydrogenase, pyruvate decarboxylase and alcohol dehydrogenase. The activities of antioxidant enzymes of root superoxide dismutase, peroxidase and catalase also decreased at S1, while superoxide dismutase and peroxidase significantly increased under T1 at S2. The ventilation of compacted soil changed soil nitrogen-fixing bacterial communities, with highest bacterial alpha diversity indices under T1. The Pearson correlation analyses indicated a positive relationship between the relative abundance of Bradyrhizobiaceae and root activity, and between unclassified_family of Rhizobiales and the root surface area, while Enterobacteriaceae had a negative impact on the root nodule number. The Pearson correlation test showed that the root surface, tips and activity positively correlated with root superoxide dismutase and peroxidase activities. These results demonstrate that soil ventilation could enhance plant root growth, the diversity and function of soil nitrogen-fixing bacterial communities. The generated results from this present study could serve as important evidence in alleviating soil hypoxia caused by compaction.

10.
Plants (Basel) ; 13(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38611468

RESUMO

Citrus is the largest fruit crop around the world, while high nitrogen (N) application in citrus orchards is widespread in many countries, which results not only in yield, quality and environmental issues but also slows down the establishment of citrus canopies in newly cultivated orchards. Thus, the objective of this study was to investigate the physiological inhibitory mechanism of excessive N application on the growth of citrus seedlings. A pot experiment with the citrus variety Orah (Orah/Citrus junos) at four N fertilization rates (0, 50, 100, and 400 mg N/kg dry soil, denoted as N0, N50, N100, and N400, respectively) was performed to evaluate the changes of root morphology, biomass, N accumulation, enzyme activities, and so on. The results showed that the N400 application significantly reduced the total biomass (from 14.24 to 6.95 g/Plant), N accumulation (from 0.65 to 0.33 g/Plant) and N use efficiency (92.69%) in citrus seedlings when compared to the N100 treatment. The partial least squares pathway model further showed that the decline of biomass and N accumulation by high N application were largely attributed to the reduction of root growth through direct and indirect effects (the goodness of fit under the model was 0.733.) rather than just soil N transformation and activity of root N uptake. These results are useful to optimize N management through a synergistic N absorption and utilization by citrus seedlings.

11.
Physiol Plant ; 176(2): e14242, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439528

RESUMO

The CONSTANS/CONSTANS-Like (CO/COL) family has been shown to play important roles in flowering, stress tolerance, fruit development and ripening in higher plants. In this study, three COL genes, MiCOL6, MiCOL7A and MiCOL7B, which each contain only one CCT domain, were isolated from mango (Mangifera indica), and their functions were investigated. MiCOL7A and MiCOL7B were expressed mainly at 20 days after flowering (DAF), and all three genes were highly expressed during the flowering induction period. The expression levels of the three genes were affected by light conditions, but only MiCOL6 exhibited a clear circadian rhythm. Overexpression of MiCOL6 promoted earlier flowering, while overexpression of MiCOL7A or MiCOL7B delayed flowering compared to that in the control lines of Arabidopsis thaliana under long-day (LD) and short-day (SD) conditions. Overexpressing MiCOL6, MiCOL7A or MiCOL7B in transgenic plants increased superoxide dismutase (SOD) and proline levels, decreased malondialdehyde (MAD) levels, and improved survival under drought and salt stress. In addition, yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) analyses showed that the MiCOL6, MiCOL7A and MiCOL7B proteins interact with several stress- and flower-related proteins. This work demonstrates the functions of MiCOL6, MiCOL7A and MiCOL7B and provides a foundation for further research on the role of mango COL genes in flowering regulation and the abiotic stress response.


Assuntos
Arabidopsis , Mangifera , Mangifera/genética , Arabidopsis/genética , Ritmo Circadiano , Secas , Flores/genética , Saccharomyces cerevisiae
12.
Int J Biol Macromol ; 262(Pt 1): 129913, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336312

RESUMO

SQUAMOSA promoter-binding protein-like (SPL) family genes play an important role in regulating plant flowering and resistance to stress. However, understanding the function of the SPL family in mango is still limited. In a previous study, two MiSPL3 genes, MiSPL3a and MiSPL3b (MiSPL3a/b), were identified in 'SiJiMi' mango and exhibited the highest expression in flowers at the initial flowering stage [24]. Therefore, in this study, we further investigated the expression pattern and gene function of MiSPL3a/b. The results showed that the expression of MiSPL3a was greatest at the end of floral bud differentiation, and MiSPL3b was expressed mainly during the flowering induction and vegetative growth stages. Subcellular localization showed that MiSPL3a/b localized to the nucleus. In addition, ectopic expression of MiSPL3a/b promoted earlier flowering in Arabidopsis thaliana by 3 d-6 d than in wild-type (WT) plants, which increased the expression of SUPPRESSOR OF CONSTANS1 (AtSOC1), FRUITFULL (AtFUL), and APETALA1 (AtAP1). MiSPL3a/b transgenic lines exhibited increased tolerance to drought, GA3, and abscisic acid (ABA) treatments but were sensitive to Pro-Ca treatment. Furthermore, protein interaction analysis revealed that MiSPL3a/b could interact with several stress-related proteins, flowering-related proteins, and the bridge protein 14-3-3. Taken together, MiSPL3a and MiSPL3b acted as positive regulators of flowering time and stress tolerance in transgenic Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Flores/genética , Regiões Promotoras Genéticas/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
ACS Sens ; 9(1): 195-205, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38166241

RESUMO

A NO2 sensor with a detection limit down to the ppb level based on pristine SnO2 has been developed through a facile poly(acrylic acid)-mediated hydrothermal method. SnO2 particles of solid microsphere, hollow microsphere, and nanosphere morphologies were synthesized, with respective constitutional crystallite of size ∼2 µm in length and 10-20 nm and ∼7 nm in diameter. All sensors show great selectivity to NO2. The hollow microsphere sensor exhibits the best performance, with medium specific surface area (SSA), followed by the nanosphere sensor with the largest SSA. This is attributed to the superposition of two opposite effects on sensor response with increased SSA: more adsorption sites and fewer electrons to be taken out with overly small crystallite that may reach complete depletion. O2 is found to speed up the response and recovery times but reduce the response because O adsorbates facilitate the adsorption/desorption of NO2 thermodynamically, and the two oxidizing gases compete in harvesting electrons from SnO2. The adverse effect of humidity can be minimized by operating the sensor at 110 °C. The response of the hollow microsphere sensor to 50 ppb of NO2 is 8.8 (Rg/Ra) at room temperature, and it increases to 15.1 at 110 °C. These findings are useful for developing other oxidizing gas semiconductor sensors.


Assuntos
Nanosferas , Oxigênio , Dióxido de Nitrogênio , Microesferas , Gases
14.
Glob Chang Biol ; 30(1): e17072, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273547

RESUMO

Tropical and subtropical forests play a crucial role in global carbon (C) pools, and their responses to warming can significantly impact C-climate feedback and predictions of future global warming. Despite earth system models projecting reductions in land C storage with warming, the magnitude of this response varies greatly between models, particularly in tropical and subtropical regions. Here, we conducted a field ecosystem-level warming experiment in a subtropical forest in southern China, by translocating mesocosms (ecosystem composed of soils and plants) across 600 m elevation gradients with temperature gradients of 2.1°C (moderate warming), to explore the response of ecosystem C dynamics of the subtropical forest to continuous 6-year warming. Compared with the control, the ecosystem C stock decreased by 3.8% under the first year of 2.1°C warming; but increased by 13.4% by the sixth year of 2.1°C warming. The increased ecosystem C stock by the sixth year of warming was mainly attributed to a combination of sustained increased plant C stock due to the maintenance of a high plant growth rate and unchanged soil C stock. The unchanged soil C stock was driven by compensating and offsetting thermal adaptation of soil microorganisms (unresponsive soil respiration and enzyme activity, and more stable microbial community), increased plant C input, and inhibitory C loss (decreased C leaching and inhibited temperature sensitivity of soil respiration) from soil drying. These results suggest that the humid subtropical forest C pool would not necessarily diminish consistently under future long-term warming. We highlight that differential and asynchronous responses of plant and soil C processes over relatively long-term periods should be considered when predicting the effects of climate warming on ecosystem C dynamics of subtropical forests.


Assuntos
Sequestro de Carbono , Ecossistema , Mudança Climática , Florestas , Carbono , Solo
15.
Org Lett ; 26(1): 51-56, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38078673

RESUMO

Herein, we present a green scheme for the divergent synthesis of two polysubstituted quinolines from a singular substrate via exploiting free-radical duality. Photocatalytically generated imine radicals produce 3,4-disubstituted quinolines via a novel rearrangement in the presence of an inorganic base. Alternatively, they react in the presence of an organic base to furnish 2,3-disubstituted quinolines. Mechanism studies support the hypothesis that the electrophilic/nucleophilic bias of free radicals can be adjusted by altering the reaction conditions.

16.
Environ Pollut ; 342: 123056, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040184

RESUMO

Endocrine disrupting chemicals like triclosan (TCS) have been thought to be an emergent environmental pollutant. The ubiquitous dissolved organic matter (DOM) is able to interrelate with TCS and hamper its phototransformation. However, how the components in DOM can inhibit the photodegradation of DOM/TCS complex is largely unknown. Herein, we discovered that TCS photodegradation with biochar-derived DOM (BDOM) was interfered by both binding affinity and reactive oxygen species (ROS) productivity. BDOM can not only stimulate TCS photodegradation by producing ROS, but also inhibit the removal of TCS through the interactions between BDOMs and TCS. The quantification of BDOM's impact on TCS photodegradation revealed that BDOM hampered TCS removal with the proportion of -7.95 to -11.24% at pH 8.5, but strengthened it to 13.20% at pH 7.0. Binding process was more easily to inhibit TCS photodegradation in molecular form, while anionic TCS photodegradation was dominated by ROS productivity. Different inhibition mechanisms were involved in TCS photodegradation depending on the components of BDOMs. The hydroxyls and aromatic carbonyls might have hindered the attack of ROS on the phenolic hydroxyl of TCS via hydrogen bond interaction or π-π electron donor-acceptor interaction. Through hydrophobic interaction, the mobile aliphatics could greatly shield TCS to prevent ROS attack by wrapping or twining TCS, playing a significant role in inhibiting TCS removal. Results from this present study can afford a new viewpoint in elucidating the function of BDOMs in the phototransformation of organics and decrease the spread of antibiotic resistance genes.


Assuntos
Carvão Vegetal , Triclosan , Poluentes Químicos da Água , Fotólise , Matéria Orgânica Dissolvida , Espécies Reativas de Oxigênio , Poluentes Químicos da Água/química
17.
Int J Biol Macromol ; 258(Pt 1): 128744, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38123033

RESUMO

The bio-based coatings of cellulose fabrics (cotton) had attracted increasing attention for multifunction and sustainability but suffered from poor durability and low efficiency. Here, the aldehyde-free and durable coatings for cotton fabrics (CPZ@CF) with satisfactory flame retardancy, antibacteria as well as wearing performance were prepared through the interfacial coordination effect where the well-organized zinc phytate complex were in situ grew on the pre-treated surface of cotton fabrics with chitosan (CS) and Zn2+. The CZP@CF exhibited excellent antibacterial activity for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with 99.99 % antibacterial rates benefiting from the synergistic effect between Zn2+ and CS. Meanwhile, even the CPZ coatings loading was only 1.5 wt%, the fire safety of CZP@CF remarkably enhanced owing to the excellent synergistic catalytic charring and free radical capture. More importantly, the antibacterial rates of CZP@CF for S. aureus and E. coli still reached 99.99 % and 91.67 % after 50 washing cycles. Additionally, this treatment method did not deteriorate the fabrics properties, including mechanical and breathability as well as wearing performance, which provided the approach to fabricate the flame retardant and antibacterial textiles with well durability and wearing performance.


Assuntos
Celulose , Quitosana , Fibra de Algodão , Escherichia coli , Staphylococcus aureus , Aldeídos , Antibacterianos
18.
Plant Sci ; 338: 111925, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37981085

RESUMO

Chloroplasts are the organelles responsible for photosynthesis and regulate normal plant growth. Although translation elongation factors play important roles in chloroplast development, functional studies of chloroplast translation elongation factors in higher plants remain very sparse. Here, we obtained a rice mutant exhibiting seedling-lethal albino phenotype and named it albino and lethal seedling 1 (als1). Consistently, low content of photosynthetic pigments, malformed chloroplasts and defective photosynthesis were observed in als1 mutant leaves. Map-based cloning experiment showed that als1 mutant had a T base insertion in Os02g0595700, causing a frame shift and premature stop codon. ALS1 encoded a GTP-binding protein EF-Tu, which acts as a translation elongation factor in chloroplast protein translation. ALS1 was found to be expressed throughout plant with highest expression level in young leaves. Moreover, ALS1 was located in chloroplast, whereas the truncated als1 could not normally be located in chloroplast. Additionally, the ALS1 mutation significantly influenced the expression of downstream genes, such as genes relevant to chlorophyll biosynthesis, photosynthesis as well as chloroplast development. These results show that ALS1 acts as a key regulator of chloroplast development and plant growth.


Assuntos
Cloroplastos , Genes de Plantas , Oryza , Proteínas de Plantas , Plântula , Clorofila/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fenótipo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Genes de Plantas/genética , Genes de Plantas/fisiologia
19.
BMC Cancer ; 23(1): 1102, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957639

RESUMO

BACKGROUND: Pancreatic adenocarcinoma (PAAD) is an aggressive solid tumour characterised by few early symptoms, high mortality, and lack of effective treatment. Therefore, it is important to identify new potential therapeutic targets and prognostic biomarkers of PAAD. METHODS: The Cancer Genome Atlas and Genotype-Tissue Expression databases were used to identify the expression and prognostic model of protocadherin 1 (PCDH1). The prognostic performance of risk factors and diagnosis of patients with PAAD were evaluated by regression analysis, nomogram, and receiver operating characteristic curve. Paraffin sections were collected from patients for immunohistochemistry (IHC) analysis. The expression of PCDH1 in cells obtained from primary tumours or metastatic biopsies was identified using single-cell RNA sequencing (scRNA-seq). Real-time quantitative polymerase chain reaction (qPCR) and western blotting were used to verify PCDH1 expression levels and the inhibitory effects of the compounds. RESULTS: The RNA and protein levels of PCDH1 were significantly higher in PAAD cells than in normal pancreatic ductal cells, similar to those observed in tissue sections from patients with PAAD. Aberrant methylation of the CpG site cg19767205 and micro-RNA (miRNA) hsa-miR-124-1 may be important reasons for the high PCDH1 expression in PAAD. Up-regulated PCDH1 promotes pancreatic cancer cell metastasis. The RNA levels of PCDH1 were significantly down-regulated following flutamide treatment. Flutamide reduced the percentage of PCDH1 RNA level in PAAD cells Panc-0813 to < 50%. In addition, the PCDH1 protein was significantly down-regulated after Panc-0813 cells were incubated with 20 µM flutamide and proves to be a potential therapeutic intervention for PAAD. CONCLUSION: PCDH1 is a key prognostic biomarker and promoter of PAAD metastasis. Additionally, flutamide may serve as a novel compound that down-regulates PCDH1 expression as a potential treatment for combating PAAD progression and metastasis.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Prognóstico , Flutamida , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , RNA , Biomarcadores , Regulação Neoplásica da Expressão Gênica , Protocaderinas , Neoplasias Pancreáticas
20.
Plants (Basel) ; 12(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38005767

RESUMO

Balanced nitrogen (N) and phosphorus (P) rates, coupled with rational fertilization methodology, could promote crop N accumulation, N use efficiency, and yield production, particularly in semi-arid and arid regions. To test these characteristics, a two-year (2018 and 2019) pot experiment was performed by growing summer maize in a rain-proof glass greenhouse under nine combined N (112, 150, and 187 kg ha-1, urea) and P (45, 60, and 75 kg ha-1 calcium superphosphate) rates and three contrasting fertilizer placements. The fertilizers were placed by broadcast on the soil surface (Broadcast), a side band on a 4 cm strip of soil surface within 7 cm from the sowing line (Side band), and a deep band on a 4 cm strip below 7 cm soil depth within 7 cm from the sowing line (Deep band). Results from three maize growth stages (eight-leaf, 45 days after sowing, DAS; tasseling, 60 DAS; and harvest, 115 DAS) showed that leaf, stem, root N accumulation, and total soil N were significantly increased under Deep band than under both Side band and Broadcast at N150P60, N187P60, N150P75, and N187P75, but not at N112P45, N150P45, N187P45, N112P60, and N112P75. Significantly greater leaf, stem, and root N accumulations were also displayed at N150 and N187 than at N112 for the same P60 or P75 under the Deep band at 60 DAS and 115 DAS; while for leaf and stem, N accumulations were greater at P75 and P60 than at P45 for the same N150 under Deep band at 45 DAS, 60 DAS, and 115 DAS. Significantly greater agronomy N use efficiency, partial factor productivity, and N use efficiency were exhibited under the Deep band than under the Side band and Broadcast at N150P75 and N187P75, but at N150P60 and N187P60 for NUE only. In addition, leaf, stem, seed, and root N concentrations positively correlated with their own N accumulations or soil N concentrations at the tasseling and harvest stages. Our results demonstrate that a synchronized N150P60, N187P60, N150P75, or N187P75 fertilization rate with Deep band placement can improve soil N availability and root N uptake, and thereby, increase aboveground N accumulation, N use efficiency, and yield production of maize, which is particularly practical for small-holder farmers globally.

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