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1.
BMC Plant Biol ; 23(1): 133, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36882694

RESUMO

BACKGROUND: Loropetalum chinense var. rubrum (L. chinense var. rubrum) is a precious, coloured-leaf native ornamental plant in the Hunan Province. We found an L. chinense var. rubrum tree with three different leaf colours: GL (green leaf), ML (mosaic leaf), and PL (purple leaf). The mechanism of leaf coloration in this plant is still unclear. Therefore, this study aimed to identify the metabolites and genes involved in determining the colour composition of L. chinense var. rubrum leaves, using phenotypic/anatomic observations, pigment content detection, and comparative metabolomics and transcriptomics. RESULTS: We observed that the mesophyll cells in PL were purple, while those in GL were green and those in ML were a mix of purple-green. The contents of chlorophyll a, b, carotenoids, and total chlorophyll in PL and ML were significantly lower than those in GL. While the anthocyanin content in PL and ML was significantly higher than that in GL. The metabolomics results showed the differences in the content of cyanidin 3-O-glucoside, delphinidin 3-O-glucoside, cyanidin 3,5-O-diglucoside, pelargonidin, and petunidin 3,5-diglucoside in ML, GL, and PL were significant. Considering that the change trend of anthocyanin content change was consistent with the leaf colour difference, we speculated that these compounds might influence the colour of L. chinense var. rubrum leaves. Using transcriptomics, we finally identified nine differentially expressed structural genes (one ANR (ANR1217); four CYP75As (CYP75A1815, CYP75A2846, CYP75A2909, and CYP75A1716); four UFGTs (UFGT1876, UFGT1649, UFGT1839, and UFGT3273) and nine transcription factors (two MYBs (MYB1057 and MYB1211), one MADS-box (MADS1235), two AP2-likes (AP2-like1779 and AP2-like2234), one bZIP (bZIP3720), two WD40s (WD2173 and WD1867) and one bHLH (bHLH1631) that might be related to flavonoid biosynthesis and then impacted the appearance of colour in L. chinense var. rubrum leaves. CONCLUSION: This study revealed potential molecular mechanisms associated with leaf coloration in L. chinense var. rubrum by analyzing differential metabolites and genes related to the anthocyanin biosynthesis pathway. It also provided a reference for research on leaf colour variation in other ornamental plants.


Assuntos
Antocianinas , Transcriptoma , Clorofila A , Metaboloma , Metabolômica
2.
Ecotoxicol Environ Saf ; 188: 109826, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31732271

RESUMO

Quinclorac (QNC) is an effective but environmentally persistent herbicide commonly used in rice production. However, few studies have investigated its environmental behavior and degradation. In the present study, we carried out microbial cultures in the presence of QNC to observe changes in soil microbiota and to identify species capable of QNC degradation by using high-throughput sequencing of the 16S rRNA. Pseudomonas was the dominant genus, and Pseudomonas putida II-2 and other species were found to be capable of mineralizing QNC as a source of carbon and energy. However, this degradation rate was slow, only reaching 51.5 ± 1.6% for 7 days at 30 °C on QNC + minimal salt medium. Achromobacter sp. QC36 co-metabolized QNC when rice straw was added into the mineral salt medium containing QNC, and a mixed culture of both strains could mineralize approximately 92% of the 50 mg/L QNC after 5 days of cultivation in the presence of rice straw, at 25-35 °C and pH 6.0-8.0. Non-phytotoxicity of tobacco after degradation of QNC by mixed strains was evidenced in a pot experiment. These results suggest that this mixed culture may be useful in QNC bioremediation and can be used as a bio-formulation for agro-economical and industrial application.


Assuntos
Achromobacter/crescimento & desenvolvimento , Herbicidas/análise , Pseudomonas putida/crescimento & desenvolvimento , Quinolinas/análise , Microbiologia do Solo , Poluentes do Solo/análise , Achromobacter/metabolismo , Biodegradação Ambiental , Oryza/crescimento & desenvolvimento , Pseudomonas putida/metabolismo , RNA Ribossômico 16S/genética , Solo/química
3.
Mar Drugs ; 17(8)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370332

RESUMO

The effect of collagen peptides (CPs) in intestinal mucosal protection has been approved in both cell and animal models. However, its structure-activity relationship and efficient peptide sequences are unclear, which hinders the in-depth study of its action mechanism and relative nutraceuticals and pharmaceuticals development. In this work, size exclusion chromatography, cation-exchange chromatography, and RP-HPLC were used to separate Alaska pollock skin-derived collagen hydrolysates based on their molecular weight, charge property, and hydrophobicity. The intestinal epithelial barrier function (IEBF) protective effect of separated peptide fractions were evaluated by tumor necrosis factor (TNF)-α-induced Caco-2 cell model. Results indicated that lower molecular weight (500-1000 Da) and higher hydrophilicity of CPs were related to better IEBF protective effect. Two high-efficiency IEBF protective peptide sequences, GPSGPQGSR and GPSGLLGPK with the corresponding molecular weights of 841.41 Da and 824.38 Da, were subsequently identified by UPLC-QToF-MS/MS. Their IEBF protective ability are comparable or even better than the currently used intestinal health supplements glutamine and arginine. The present findings suggested that the hydrophilic CPs, with molecular weight between 500 Da to 1000 Da, should be preferred in IEBF protective peptides preparation. GPSGPQGSR and GPSGLLGPK might have the potential of being IEBF protective ingredients used in intestinal health supplements and drugs.


Assuntos
Colágeno/farmacologia , Gadiformes , Mucosa Intestinal/efeitos dos fármacos , Peptídeos/farmacologia , Alaska , Animais , Células CACO-2 , Colágeno/química , Colágeno/isolamento & purificação , Suplementos Nutricionais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Peso Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Permeabilidade/efeitos dos fármacos , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem
4.
J Interv Cardiol ; 31(6): 737-746, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30251273

RESUMO

INSTRUCTION: Several factors affect the in-stent intimal healing process after drug-eluting stents (DESs) implantation. We hope to investigate the influence of plaque characteristics on subsequent heterogeneous neointimal hyperplasia (NIH) using optical coherence tomography (OCT). METHODS: The study population consisted 217 patients with single-vessel de novo lesions who underwent both pre-procedural OCT scan and 12-month follow-up OCT examination. NIH is defined as at least five consecutive cross-sectional images with no less than 100µm neointimal thickness. According to OCT follow-up, patients were divided into three groups: neointima-covered group, homogeneous, and heterogeneous NIH group. RESULTS: 102 patients were categorized in neointima-covered group, 91 and 24 patients in homogeneous and heterogeneous group, respectively. Time interval between OCT scans was similar (P = 0.55). No significant differences in the patients' age, gender, comorbidities, laboratory findings, procedural, and lesion-related findings were found among these three groups. Heterogeneous group tended to have more subjects presented as acute coronary syndrome (ACS) (P = 0.04) and mean macrophage grade was higher in this group (P = 0.01). While no statistically significant difference concerning mean intimal thickness (P = 0.21) or neointimal burden (P = 0.73) was found between homogeneous and heterogeneous group. Multivariate logistic regression analysis showed that mean macrophage grade (OR: 2.26, 95%CI: 1.12 to 4.53, P = 0.02) and initial clinical presentation of ACS (OR: 2.81, 95%CI: 1.03 to 7.72, P = 0.04) were significant independent risk factors for heterogeneous NIH. CONCLUSION: Mean macrophage grade measured by OCT as a semi-quantitative morphological risk factor, as well as clinical presentation of ACS, was associated with in-stent neointimal heterogeneity after DES implantation.


Assuntos
Doença da Artéria Coronariana/patologia , Stents Farmacológicos/efeitos adversos , Neointima/patologia , Placa Aterosclerótica/patologia , Tomografia de Coerência Óptica/métodos , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Feminino , Seguimentos , Humanos , Hiperplasia/patologia , Masculino , Pessoa de Meia-Idade , Neointima/diagnóstico por imagem , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Túnica Íntima/patologia
5.
J Sci Food Agric ; 95(7): 1469-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25065672

RESUMO

BACKGROUND: Rhamnolipids were reported to have evident antifungal activity. The efficacy of rhamnolipids against Alternaria alternata and their possible mechanisms involved were investigated. RESULT: The decay incidences of A. alternata of cherry tomatoes (Lycopersicon esculentum) treated by rhamnolipids were significantly reduced. The in vitro assays showed that rhamnolipids inhibited fungal growth on solid medium and prevented spore germination and mycelium growth in liquid medium. In addition, the combination of rhamnolipids and essential oil had a synergistic effect leading to the decrease of fungicidal concentrations of laurel oil. Scanning electron microscopy and transmission electron microscopy observations of the pathogen revealed significant morphological and cell structural alterations in the hyphae. Compared to the control, the content of nucleic acid in supernatant of the suspension of A. alternata increased, while the content of DNA and protein of mycelium decreased, which was in agreement with electrolyte leakage experiments. CONCLUSION: Rhamnolipids could be an alternative to chemicals for controlling post-harvest phytopathogenic fungi on fruits and vegetables.


Assuntos
Alternaria/efeitos dos fármacos , Antifúngicos/farmacologia , Conservação de Alimentos/métodos , Frutas/microbiologia , Fungicidas Industriais/farmacologia , Glicolipídeos/farmacologia , Solanum lycopersicum/microbiologia , Alternaria/genética , Alternaria/crescimento & desenvolvimento , Microbiologia de Alimentos , Estruturas Fúngicas/efeitos dos fármacos , Estruturas Fúngicas/crescimento & desenvolvimento , Humanos , Óleos Voláteis/farmacologia , Sesquiterpenos/farmacologia
6.
J Sci Food Agric ; 94(7): 1403-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25525652

RESUMO

BACKGROUND: Many essential oils were reported to be used as natural, environmental friendly antimicrobial agents. The antifungal activity in vitro and in vivo of an essential oil extracted from Chinese local Laurus nobilis leaves against Alternaria alternata has been studied. RESULT: The main components of the essential oil were investigated by means of gas chromatography­mass spectrometry and 14 components were identified. The main ones were eugenol, caryophyllene and cinnamaldehyde. The antifungal test showed that at 800 µg mL−1 of L. nobilis oil completely inhibited the growth of A. alternata. In addition, the conidial germination of the pathogen was significantly inhibited at 200 µgmL−1, and the weight of mycelia efficiently decreased at 500 µgmL−1. The in vivo assay indicated that 500 µg mL−1 L. nobilis oil was effective in protecting cherry tomatoes (Lycopersicon esculentum)from infection of A. alternata, with an inhibition ratio of 33.9%. Scanning electron microscopy observations of the pathogen revealed significant morphological alterations in the hyphae. CONCLUSION: This work suggested that L. nobilis oil could be used as a potential fungicide to control the post-harvest disease caused by A. alternata.


Assuntos
Alternaria/efeitos dos fármacos , Frutas/microbiologia , Fungicidas Industriais/farmacologia , Laurus/química , Óleos Voláteis/farmacologia , Solanum lycopersicum/microbiologia , Alternaria/fisiologia , Alternaria/ultraestrutura , Conservação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Hifas/fisiologia , Hifas/ultraestrutura , Esporos Fúngicos/fisiologia
7.
J Sci Food Agric ; 94(12): 2441-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24425449

RESUMO

BACKGROUND: Essential oils such as citronella oil exhibit antifungal activity and are potential alternative inhibitors to chemical synthetic fungicides for controlling postharvest diseases. In this study the antifungal activity of citronella oil against Alternaria alternata was investigated. RESULTS: In vitro, citronella oil showed strong inhibition activity against A. alternata. The minimum inhibitory concentration in potato dextrose agar and potato dextrose broth medium was determined as 1 and 0.8 µL mL(-1) respectively. In vivo the disease incidence of Lycopersicon esculentum (cherry tomato) treated with citronella oil was significantly (P < 0.05) reduced compared with the control after 5 days of storage at 25 °C and 95% relative humidity. The disease incidence at oil concentrations of 0.2-1.5 µL mL(-1) was 88-48%. The most effective dosage of the oil was 1.5 µL mL(-1), with 52% reduction, and the oil had no negative effect on fruit quality. Scanning electron microscopy observation revealed considerably abnormal mycelial morphology. CONCLUSION: Citronella oil can significantly inhibit A. alternata in vitro and in vivo and has potential as a promising natural product for controlling black rot in cherry tomato.


Assuntos
Alternaria/efeitos dos fármacos , Frutas/microbiologia , Fungicidas Industriais/farmacologia , Óleos Voláteis/farmacologia , Doenças das Plantas/microbiologia , Óleos de Plantas/farmacologia , Solanum lycopersicum/microbiologia , Antifúngicos/farmacologia , Conservação de Alimentos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
8.
Adv Mater ; 36(1): e2309038, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37970742

RESUMO

Despite being extensively explored as cathodes in batteries, sulfur (S) can function as a low-potential anode by changing charge carriers in electrolytes. Here, a highly reversible S anode that fully converts from S8 0 to S2- in static aqueous S-I2 batteries by using Na+ as the charge carrier is reported. This S anode exhibits a low potential of -0.5 V (vs standard hydrogen electrode) and a near-to-theoretical capacity of 1404 mA h g-1 . Importantly, it shows significant advantages over the widely used Zn anode in aqueous media by obviating dendrite formation and H2 evolution. To suppress "shuttle effects" faced by both S and I2 electrodes, a scalable sulfonated polysulfone (SPSF) membrane is proposed, which is superior to commercial Nafion in cost (US$1.82 m-2  vs $3500 m-2 ) and environmental benignity. Because of its ultra-high selectivity in blocking polysulfides/iodides, the battery with SPSF displays excellent cycling stability. Even under 100% depth of discharge, the battery demonstrates high capacity retention of 87.6% over 500 cycles, outperforming Zn-I2 batteries with 3.1% capacity under the same conditions. These findings broaden anode options beyond metals for high-energy, low-cost, and fast-chargeable batteries.

9.
Front Pharmacol ; 15: 1358640, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384290

RESUMO

Moutan Cortex (MC) has been used in treating inflammation-associated diseases and conditions in China and other Southeast Asian countries. However, the active components of its anti-inflammatory effect are still unclear. The study aimed to screen and identify potential cyclooxygenase-2 (COX-2) inhibitors in MC extract. The effect of MC on COX-2 was determined in vitro by COX-2 inhibitory assays, followed by bio-affinity ultrafiltration in combination with ultra-performance liquid chromatography-mass spectrometry (BAUF-UPLC-MS). To verify the reliability of the constructed approach, celecoxib was applied as the positive control, in contrast to adenosine which served as the negative control in this study. The bioactivity of the MC components was validated in vitro by COX-2 inhibitor assay and RAW264.7 cells. Their in vivo anti-inflammatory activity was also evaluated using LPS-induced zebrafish inflammation models. Finally, molecular docking was hired to further explore the internal interactions between the components and COX-2 residues. The MC extract showed an evident COX-2-inhibitory effect in a concentration-dependent manner. A total of 11 potential COX-2 inhibitors were eventually identified in MC extract. The COX-2 inhibitory activity of five components, namely, gallic acid (GA), methyl gallate (MG), galloylpaeoniflorin (GP), 1,2,3,6-Tetra-O-galloyl-ß-D-glucose (TGG), and 1,2,3,4,6-Penta-O-galloyl-ß-D-glucopyranose (PGG), were validated through both in vitro assays and experiments using zebrafish models. Besides, the molecular docking analysis revealed that the potential inhibitors in MC could effectively inhibit COX-2 by interacting with specific residues, similar to the mechanism of action exhibited by celecoxib. In conclusion, BAUF-UPLC-MS combining the molecular docking is an efficient approach to discover enzyme inhibitors from traditional herbs and understand the mechanism of action.

10.
ACS Appl Mater Interfaces ; 16(12): 15143-15155, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38481099

RESUMO

Realizing controllable input of botanical pesticides is conducive to improving pesticide utilization, reducing pesticide residues, and avoiding environmental pollution but is extremely challenging. Herein, we constructed a smart pesticide-controlled release platform (namely, SCRP) for enhanced treatment of tobacco black shank based on encapsulating honokiol (HON) with mesoporous hollow structured silica nanospheres covered with pectin and chitosan oligosaccharide (COS). The SCRP has a loading capacity of 12.64% for HON and could effectively protect HON from photolysis. Owing to the pH- and pectinase-sensitive property of the pectin, the SCRP could smartly release HON in response to a low pH or a rich pectinase environment in the black shank-affected area. Consequently, the SCRP effectively inhibits the infection of P. nicotianae on tobacco with a controlled rate for tobacco black shank of up to 87.50%, which is mainly due to the SCRP's capability in accumulating ROS, changing cell membrane permeability, and affecting energy metabolism. In addition, SCRP is biocompatible, and the COS layer enables SCRP to show a significant growth-promoting effect on tobacco. These results indicate that the development of a stimuli-responsive controlled pesticide release system for plant disease control is of great potential and value for practical agriculture production.


Assuntos
Praguicidas , Praguicidas/farmacologia , Preparações de Ação Retardada/farmacologia , Preparações de Ação Retardada/química , Poligalacturonase , Agricultura , Pectinas
11.
Environ Sci Pollut Res Int ; 30(13): 35985-35995, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36542280

RESUMO

Increasing food output while reducing agricultural carbon emissions (ACE) is a major challenge to achieving green agriculture in China. Previously unexplored research regarding the relationship between agricultural production outsourcing services (APOS) and ACE is investigated using household microsurvey data in China and econometric methods, and the influencing mechanism is also tested empirically. The results reveal that APOS increases the total ACE and reduces ACE per unit area. The mechanism test shows that APOS are beneficial to the expansion of rice planting areas and farmers' adoption of agricultural green production techniques. The increasing effect of rice planting area on ACE was greater than the decreasing effect of green production techniques. In the future, China should accelerate the selection and breeding of rice varieties with low carbon emissions to reduce the increase of ACE caused by large-scale land management in the process of APOS development. Policy support and subsidies should be strengthened for APOS organizations to purchase green production techniques, so as to further drive farmers to adopt green production techniques and reduce ACE. It is also necessary for China to encourage small-scale farmers to outsource their agricultural production activities to APOS organizations. The role of collective action consciousness of agricultural production in increasing the supply capacity of APOS organizations should be enhanced.


Assuntos
Oryza , Serviços Terceirizados , Carbono , Melhoramento Vegetal , Agricultura/métodos , Fazendeiros , China
12.
Foods ; 12(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37959099

RESUMO

Chilled pork is frequently contaminated with Pseudomonas fragi and Pseudomonas fluorescens. In this study, the bactericidal efficacy and mechanisms of non-electrolytic slightly acidic hypochlorous water (NE-SAHW) against two strains of these two species were evaluated. The results showed that the antibacterial efficacy of NE-SAHW was positively correlated with the concentration level of NE-SAHW and negatively correlated with the initial populations of the strains. The strains of small populations were completely inhibited when provided with each level of NE-SAHW. The killed cells of P. fragi were 0.94, 1.39, 4.02, and 5.60 log10 CFU/mL, respectively, and of P. fluorescens they were 1.21, 1.52, 4.14, and 5.74 log10 CFU/mL, respectively, when the initial populations of the strains were at high levels (about 7 log10 CFU/mL). Both strains were completely killed within 12 s with the available chlorine concentration (ACC) of 50 mg/L of NE-SAHW. Morphological changes in both cells were observed by using a Scanning Electron Microscope (SEM) and it was discovered that the cell membranes were damaged, which led to the leakage of the intracellular substances, including K+, nucleic acid, and protein. In terms of the Fourier Transform Infrared Spectroscopy (FTIR) results, NE-SAHW destroyed the structures of membrane proteins and cell structure proteins, and influenced the composition of polysaccharides. The bacteria were definitely dead after treatment by NE-SAHW compared to the control according to the results of flow cytometry. These results demonstrated the potential bactericidal property of NE-SAHW when applied to the meat and other food sterilization industries.

13.
Foods ; 12(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37761079

RESUMO

Allium mongolicum Regel (A. mongolicum) is a healthy edible plant but highly perishable with a short shelf life of 1-2 d. Modified atmosphere packaging (MAP) could inhibit the postharvest senescence and decay of the vegetables. Thus, the aim of this study was to apply MAP with different gas permeabilities to the storage of A. mongolicum and evaluate its effects on maintaining microbial communities and the postharvest quality of A. mongolicum. The results showed that polypropylene/poly(butylene adipate-co-terephthalate) (PP/PBAT, abbreviated as PAT) MAP was suitable for the storage of A. mongolicum by establishing an optimal atmosphere of 0.5-0.6% O2 and 6.2-7.1% CO2 in the bag. It could delay the postharvest senescence of A. mongolicum and maintain its quality by slowing down its respiration rate and weight loss, reducing cell membrane permeability and lipid peroxidation, maintaining the cell wall, and reducing infection and the growth of microorganisms. However, A. mongolicum in HPT was more perishable than that in PAT during storage. Pseudomonas was found to be the main spoilage bacteria, and they could also be effectively inhibited by PAT-MAP. The next-generation sequencing results also showed the growth of Escherichia-Shigella, Clostridium sensu stricto 1, Streptococcus, Aureobasidium, Didymella, and Fusarium, responsible for A. mongolicum decay or human disease, was well inhibited by PAT-MAP. The results suggested that PAT-MAP could be used to maintain microbial diversity and the postharvest quality of A. mongolicum under cold storage conditions. It provided a feasible solution for the preservation, food quality, and safety control of A. mongolicum.

14.
PeerJ ; 11: e14834, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36815976

RESUMO

This research mainly focused on the leaf color change and photosystem function differentiation between Loropetalum chinense and its variety L. chinense var. rubrum under heat stress, which were tightly concerned about their ornamental traits and growth. L. chinense 'Xiangnong Xiangyun' (X) and L. chinense var. rubrum 'Xiangnong Fendai' (F) and L. chinense var. rubrum 'Hei Zhenzhu' (H) were chosen to be experimented on to investigate whether leaf color morphology and pigment composition could influence the adaptability of plants to high temperature in order to select foliage plants which posses stable leaf color and better adaptability for hot regions. The plants were cultured in hot environment (40 °C/33 °C, day/night) and normal environment (25 °C/18 °C, day/night). Phenotype and anatomic observation of three cultivars were made and leaf color indices and pigment contents were measured. During the experiment, H and F gradually turned green, total anthocyanins contents significantly decreased in them, however, chlorophyll b contents increased in all three cultivars. In addition, the initial fluorescence (Fo) decreased in X, while increased in H and F. For the maximum fluorescence (Fm) and maximum photochemical efficiency of PSII (Fv/Fm), they only increased in H and decreased in both F and X. The non-photochemical chlorophyll fluorescence quenching (NPQ) also increased in H and decreased in F. For X, it increased at first then gradually decreased. The coefficient of photochemical quenching all increased at first then gradually decreased. Correlation analysis between showed that there was relatively strong connection between anthocyanins, flavonoids and chlorophyll fluorescence parameters, especially NPQ, proved anthocyanins and flavonoids might not only involved in enriching leaf color, but also interfered with the protection of photosystem. Generally speaking, we found higher anthocyanin and flavonoids content level not only dramatically enriched the leaf color of L. chinense var. rubrum cultivars, but also offered more potential antioxidant to keep their normal growth when encountered heat stress.


Assuntos
Antocianinas , Fotossíntese , Antocianinas/análise , Clorofila/análise , Folhas de Planta/química , Resposta ao Choque Térmico
15.
Artigo em Inglês | MEDLINE | ID: mdl-35805456

RESUMO

Based on the Web of Science core collection database, this paper retrieves 349 research papers on terraced fields published during 1991-2020. Keyword co-occurrence analysis, cluster analysis, and thematic evolutionary analysis were used to identify the evolutionary path of terrace research. The findings were as follows: (1) In the past 20 years, the study of terraced fields has shown an upward trend. The number of annual published papers during 2012-2020 was much more than that during 1991-2011, but papers during 1991-2011 were more academically influential than those during 2012-2020. (2) Regional analysis showed that terrace research in China is the most abundant currently, and is mainly focused on agricultural production, agricultural engineering, cultural tourism, and ecological environment. (3) Keyword co-occurrence analysis showed that terrace landscape, terrace agriculture, terrace abandonment, land use change, soil and water conservation, and sustainable utilization of typical terraces are the main modules of current terrace studies. (4) In a temporal dynamic perspective, terrace research presented 10 main evolutionary paths during 1991-2020, reflecting the trend of terrace research towards sustainable terrace development of ecological agriculture and ecosystem service. (5) Finally, this paper suggests that here is a need to deepen studies on terrace ecosystem services and human well-being based on their structure and processes, to analyze the interaction and comprehensive effect of natural process and humanistic driving forces on terrace abandonment, and to explore the multi-functional benefits and sustainable management of high quality terraced landscape.


Assuntos
Agricultura , Ecossistema , Bibliometria , Evolução Biológica , Humanos , Solo
16.
Artigo em Inglês | MEDLINE | ID: mdl-35328906

RESUMO

Land consolidation is widely used as a powerful tool for land use management in many countries. In order to objectively reveal the current research status in the field of land consolidation, this paper uses the Bibliometrix and Biblioshiny software packages, and VOSviewer to analyze the literature in the field of land consolidation in the last 20 years of the Web of Science Core Collection Database. The results show that: (1) In the past two decades, the annual publication of papers on land consolidation rose. It can be divided into three stages: 2000-2007 for the embryonic period, 2008-2012 for the long-term, and 2013-2020 for the high-yield period. (2) Land consolidation studies covered 68 countries or regions. The top three countries were China, Poland, and the United States. China and the United States played an important role in international cooperation in the field of land consolidation, and Turkey mainly conducted independent research in the field of land consolidation. (3) Land consolidation, reclamation, China, remote sensing, and land fragmentation were the high-frequency keywords in the field of land consolidation in recent years. (4) The research focusing on the field of land consolidation involved its development course, its impact on ecosystem services, and the evaluation of its benefits. (5) The theme of land consolidation studies was shunted and evolved over time, and nine evolution paths could be summarized in the studies of cultivated land fragmentation, development course of land consolidation, and impacts of land consolidation on soil. Finally, this paper predicted the future research directions of land consolidation: exploring new methods for evaluating the benefits of land consolidation, the scale effects of the impact of land consolidation on ecosystem services, research on the mechanism and comprehensive effects of land consolidation on soil, research on land consolidation and rural revitalization, and land consolidation theory research.


Assuntos
Bibliometria , Ecossistema , China , Bases de Dados Factuais , Solo , Estados Unidos
17.
J Colloid Interface Sci ; 610: 136-151, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34922071

RESUMO

The development of visible-light response photocatalysts with a high catalytic performance and long-term cyclic stability is of great significance in the field of energy and environmental protection. Inspired by photosynthesis, a novel three-dimensional coral zirconium-based metal organic framework (MOF) was synthesized using a double-ligand strategy. The optimal sample, Zr-TCPP-bpydc (2:1), (the ratio of tetra-(4-carboxyphenyl) porphyrin to 2,2'-bipyridine-5,5'-dicarboxylic acid is 2:1) shows an excellent photocatalytic activity under visible light irradiation, and the effects of the amount of photocatalyst, pH and concentration on the degradation rate were investigated under the optimum conditions. It has a high degradation rate of tetracycline (98.12% for tetracycline and 96.74% for ofloxacin), which is 2.11 times higher than that of single ligand Zr-bpydc (zirconium-based MOF containing only 2,2'-bipyridine-5,5'-dicarboxylic acid). More importantly, it also has a good H2 evolution rate (213.68 µmol g-1h-1) and CO2 reduction (35.81 µmol g-1h-1). In addition, the intermediate pathway of degradation, photocatalytic enhancement mechanism and cycle stability were deeply studied by liquid chromatography-mass spectrometry (LC-MS), electron spin resonance spectroscopy (ESR), linear sweep voltammetry (LSV) and recycling tests. The synthesis of a three-dimensional biomimetic coral zirconium-based MOF material will provide guidance for the development of new, promising, and natural ideal photocatalytic materials.


Assuntos
Recuperação e Remediação Ambiental , Estruturas Metalorgânicas , Biomimética , Ligantes , Zircônio
18.
Front Plant Sci ; 13: 1000160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36457526

RESUMO

Introduction: Loropetalum chinense var. rubrum blooms 2-3 times a year, among which the autumn flowering period has great potential for exploitation, but the number of flowers in the autumn flowering period is much smaller than that in the spring flowering period. Methods: Using 'Hei Zhenzhu' and 'Xiangnong Xiangyun' as experimental materials, the winter growth environment of L. chinense var. rubrum in Changsha, Hunan Province was simulated by setting a low temperature of 6-10°C in an artificial climate chamber to investigate the effect of winter low temperature on the flowering traits and related gene expression of L. chinense var. rubrum. Results: The results showed that after 45 days of low temperature culture and a subsequent period of 25°C greenhouse culture, flower buds and flowers started to appear on days 24 and 33 of 25°C greenhouse culture for 'Hei Zhenzhu', and flower buds and flowers started to appear on days 21 and 33 of 25°C greenhouse culture for 'Xiangnong Xiangyun'. The absolute growth rate of buds showed a 'Up-Down' pattern during the 7-28 days of low temperature culture; the chlorophyll fluorescence decay rate (Rfd) of both materials showed a 'Down-Up-Down' pattern during this period. The non-photochemical quenching coefficient (NPQ) showed the same trend as Rfd, and the photochemical quenching coefficient (QP) fluctuated above and below 0.05. The expression of AP1 and FT similar genes of L. chinense var. rubrum gradually increased after the beginning of low temperature culture, reaching the highest expression on day 14 and day 28, respectively, and the expression of both in the experimental group was higher than that in the control group. The expressions of FLC, SVP and TFL1 similar genes all decreased gradually with low temperature culture, among which the expressions of FLC similar genes and TFL1 similar genes in the experimental group were extremely significantly lower than those in the control group; in the experimental group, the expressions of GA3 similar genes were all extremely significantly higher than those in the control group, and the expressions all increased with the increase of low temperature culture time. Discussion: We found that the high expression of gibberellin genes may play an important role in the process of low temperature promotion of L. chinense var. rubrum flowering, and in the future, it may be possible to regulate L. chinense var. rubrum flowering by simply spraying exogenous gibberellin instead of the promotion effect of low temperature.

19.
IEEE Trans Neural Netw Learn Syst ; 32(6): 2430-2442, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32749966

RESUMO

Correlation filter (CF) has recently been widely used for visual tracking. The estimation of the search window and the filter-learning strategies is the key component of the CF trackers. Nevertheless, prevalent CF models separately address these issues in heuristic manners. The commonly used CF models directly set the estimated location in the previous frame as the search center for the current one. Moreover, these models usually rely on simple and fixed regularization for filter learning, and thus, their performance is compromised by the search window size and optimization heuristics. To break these limits, this article proposes a location-aware and regularization-adaptive CF (LRCF) for robust visual tracking. LRCF establishes a novel bilevel optimization model to address simultaneously the location-estimation and filter-training problems. We prove that our bilevel formulation can successfully obtain a globally converged CF and the corresponding object location in a collaborative manner. Moreover, based on the LRCF framework, we design two trackers named LRCF-S and LRCF-SA and a series of comparisons to prove the flexibility and effectiveness of the LRCF framework. Extensive experiments on different challenging benchmark data sets demonstrate that our LRCF trackers perform favorably against the state-of-the-art methods in practice.


Assuntos
Desempenho Psicomotor , Algoritmos , Inteligência Artificial , Humanos , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Modelos Neurológicos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão
20.
Plants (Basel) ; 10(4)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924154

RESUMO

Wild soybean (Glycine soja Sieb.et Zucc; WS) has been used as a traditional food in China for many years and contains significantly higher levels of isoflavones than cultivated soybean (Glycine max; CS), but the secondary metabolites, including flavonoids and the phenolic composition differences between them, remain unclear. The results showed that WS possessed significantly higher total phenolic and flavonoid content and exhibited better antioxidant and α-glucosidase inhibition activities as well as excellent protective effects against H2O2-induced oxidative injury in a human endothelial cell line. Through metabolomic analysis, 642 metabolites were identified, and 238 showed differential expression, with 151 upregulated and 87 downregulated. A total of 79 flavonoid compounds were identified, 42 of which were upregulated in WS. 2'-Hydroxygenistein, garbanzol, protocatechuic aldehyde, ligustilide, and resveratrol were the most discriminated compounds in WS. The metabolic pathway analysis of differential metabolites related to the biosynthesis of flavonoids and phenolic acids were the biosynthesis of phenylpropanoids, flavonoids, isoflavonoids, flavones, and flavonols. This study substantially elucidated differences in the content of flavonoids and biological activities between WS and CS, which is useful information for the effective utilization of these two black soybean species in food processing.

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