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1.
Org Biomol Chem ; 22(20): 4179-4189, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38716654

RESUMO

Aspergillus versicolor, an endophytic fungus associated with the herbal medicine Pedicularis sylvatica, produced four new polyketides, aspeversins A-D (1-2 and 5-6) and four known compounds, O-methylaverufin (2), aversin (3), varilactone A (7) and spirosorbicillinol A (8). Their structures were elucidated by extensive spectroscopic data analysis, and their absolute configurations were determined by calculated electronic circular dichroism (ECD) and Mo2(AcO)4-induced CD data. Compound 5 was found to exhibit α-glucosidase inhibitory activity with an IC50 value of 25.57 µM. An enzyme kinetic study indicated that 5 was a typical uncompetitive inhibitor toward α-glucosidase, which was supported by a molecular docking study. Moreover, compounds 1-3 and 5 also improved the cell viability of PC12 cells on a 1-methyl-4-phenylpyridinium (MPP+)-induced Parkinson's disease model, indicating their neuroprotective potential as antiparkinsonian agents.


Assuntos
Aspergillus , Inibidores de Glicosídeo Hidrolases , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores , Policetídeos , alfa-Glucosidases , Aspergillus/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Policetídeos/farmacologia , Policetídeos/química , Policetídeos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Células PC12 , Animais , Ratos , alfa-Glucosidases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Estrutura Molecular
2.
Nat Commun ; 14(1): 8477, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123561

RESUMO

Following acute retinal damage, zebrafish possess the ability to regenerate all neuronal subtypes through Müller glia (MG) reprogramming and asymmetric cell division that produces a multipotent Müller glia-derived neuronal progenitor cell (MGPC). This raises three key questions. First, do MG reprogram to a developmental retinal progenitor cell (RPC) state? Second, to what extent does regeneration recapitulate retinal development? And finally, does loss of different retinal cell subtypes induce unique MG regeneration responses? We examined these questions by performing single-nuclear and single-cell RNA-Seq and ATAC-Seq in both developing and regenerating retinas. Here we show that injury induces MG to reprogram to a state similar to late-stage RPCs. However, there are major transcriptional differences between MGPCs and RPCs, as well as major transcriptional differences between activated MG and MGPCs when different retinal cell subtypes are damaged. Validation of candidate genes confirmed that loss of different subtypes induces differences in transcription factor gene expression and regeneration outcomes.


Assuntos
Redes Reguladoras de Genes , Peixe-Zebra , Animais , Peixe-Zebra/genética , Retina/metabolismo , Neurogênese/genética , Neuroglia/metabolismo , Proliferação de Células/fisiologia , Células Ependimogliais/metabolismo
3.
Res Sq ; 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37790324

RESUMO

Following acute retinal damage, zebrafish possess the ability to regenerate all neuronal subtypes. This regeneration requires Müller glia (MG) to reprogram and divide asymmetrically to produce a multipotent Müller glia-derived neuronal progenitor cell (MGPC). This raises three key questions. First, does loss of different retinal cell subtypes induce unique MG regeneration responses? Second, do MG reprogram to a developmental retinal progenitor cell state? And finally, to what extent does regeneration recapitulate retinal development? We examined these questions by performing single-nuclear and single-cell RNA-Seq and ATAC-Seq in both developing and regenerating retinas. While MG reprogram to a state similar to late-stage retinal progenitors in developing retinas, there are transcriptional differences between reprogrammed MG/MGPCs and late progenitors, as well as reprogrammed MG in outer and inner retinal damage models. Validation of candidate genes confirmed that loss of different subtypes induces differences in transcription factor gene expression and regeneration outcomes. This work identifies major differences between gene regulatory networks activated following the selective loss of different subtypes of retina neurons, as well as between retinal regeneration and development.

4.
J Environ Manage ; 345: 118916, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37690244

RESUMO

The commitment to waste management has gained increasing momentum as global waste generation continues to skyrocket and threaten the environment. However, detailed assessments and clear insights remain absent to address the global waste utilization conundrum. This study evaluated the impact-oriented energy, carbon, and water (ECW) footprints of three typical scenarios for a waste recycling activity (i.e., waste rubber recycling) from environmental and economic dimensions, and explored key factors, nexus characteristics, and optimization measures. Results indicated that the rubber powder as an asphalt modifier scenario had a 93% greater environmental impact and 87% higher economic cost compared with the pyrolysis and reclaimed rubber production scenarios. Key processes, such as direct processes, electricity generation, and transportation, were identified as the major contributors to the ECW footprints, with the internal costs of raw materials, equipment, and taxes coupled with the external costs of human health dominating the economic impact. The nexus analysis results highlighted the urgent need to optimize the energy system for waste rubber recycling. Greening the production process revealed the benefits, with natural additives mitigating 85% of the environmental burden and 97% of the external costs compared with conventional additives. Industrial green microgrids, clean energy generation, proximity waste management, and electrified transportation were explored to foster sustainable optimization of waste rubber recycling systems. Moreover, a joint tax-subsidy mechanism for rubber production-recycling systems can stimulate recycling-oriented product design and increase the motivation to recycle waste rubber.


Assuntos
Pegada de Carbono , Borracha , Humanos , Impostos , Carbono , Eletricidade
5.
bioRxiv ; 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37609307

RESUMO

Following acute retinal damage, zebrafish possess the ability to regenerate all neuronal subtypes. This regeneration requires Müller glia (MG) to reprogram and divide asymmetrically to produce a multipotent Müller glia-derived neuronal progenitor cell (MGPC). This raises three key questions. First, does loss of different retinal cell subtypes induce unique MG regeneration responses? Second, do MG reprogram to a developmental retinal progenitor cell state? And finally, to what extent does regeneration recapitulate retinal development? We examined these questions by performing single-nuclear and single-cell RNA-Seq and ATAC-Seq in both developing and regenerating retinas. While MG reprogram to a state similar to late-stage retinal progenitors in developing retinas, there are transcriptional differences between reprogrammed MG/MGPCs and late progenitors, as well as reprogrammed MG in outer and inner retinal damage models. Validation of candidate genes confirmed that loss of different subtypes induces differences in transcription factor gene expression and regeneration outcomes. This work identifies major differences between gene regulatory networks activated following the selective loss of different subtypes of retina neurons, as well as between retinal regeneration and development.

6.
Bioinformatics ; 39(9)2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37610325

RESUMO

MOTIVATION: Single-cell sequencing technology has become a routine in studying many biological problems. A core step of analyzing single-cell data is the assignment of cell clusters to specific cell types. Reference-based methods are proposed for predicting cell types for single-cell clusters. However, the scalability and lack of preprocessed reference datasets prevent them from being practical and easy to use. RESULTS: Here, we introduce a reference-based cell annotation web server, CellAnn, which is super-fast and easy to use. CellAnn contains a comprehensive reference database with 204 human and 191 mouse single-cell datasets. These reference datasets cover 32 organs. Furthermore, we developed a cluster-to-cluster alignment method to transfer cell labels from the reference to the query datasets, which is superior to the existing methods with higher accuracy and higher scalability. Finally, CellAnn is an online tool that integrates all the procedures in cell annotation, including reference searching, transferring cell labels, visualizing results, and harmonizing cell annotation labels. Through the user-friendly interface, users can identify the best annotation by cross-validating with multiple reference datasets. We believe that CellAnn can greatly facilitate single-cell sequencing data analysis. AVAILABILITY AND IMPLEMENTATION: The web server is available at www.cellann.io, and the source code is available at https://github.com/Pinlyu3/CellAnn_shinyapp.


Assuntos
Computadores , Software , Humanos , Animais , Camundongos , Bases de Dados Factuais , Análise de Célula Única
7.
Phytochemistry ; 211: 113690, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150432

RESUMO

Nigrograna sp. LY66, an endophytic fungus associated with the herbal medicinal plant Clematis shensiensis, produced four undescribed steroids, nigergostanes A-D (1-4), including an unusual ketal-containing nigergostane (1), and four undescribed sesquiterpenoids decorated with cyclohexanone motifs, nigbisabolanes A-D (7-10), along with three known compounds, 23R-hydroxy-(20Z,24R)-ergosta-4,6,8(14),20(22)-tetraen-3-one (5), ergosta-5,7,22-trien-3ß-ol (6), and curculonone A (11). The structures and absolute configurations of these undescribed compounds were confirmed using spectroscopic data (NMR and HRESIMS), modified Mosher's method, and ECD experiments. Additionally, compounds 5 and 8 displayed significant inhibition of nitric oxide generation in lipopolysaccharide-induced BV-2 microglial cells with IC50 values of 2.8 and 2.7 µM, respectively, and is thus more potent than that of the positive control, quercetin (IC50 = 8.77 µM). A molecular docking study revealed that 23-OH of 5 binds to the Y347 residue of inducible nitric oxide synthase (iNOS), whereas the 2-OH and 9,10-diol moieties of 8 bind to R381 and W463 and haeme residues of iNOS, respectively, which has rarely been reported in previous studies. These findings provide a set of undescribed lead compounds that can be developed into anti-neuroinflammatory agents.


Assuntos
Ascomicetos , Clematis , Fitosteróis , Sesquiterpenos , Esteróis , Clematis/metabolismo , Simulação de Acoplamento Molecular , Ascomicetos/metabolismo , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Óxido Nítrico
8.
J Agric Food Chem ; 71(11): 4615-4624, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36945879

RESUMO

Phaeosphaeria sp., a lichen-associated fungus, produced six skeletally new dimeric spiciferones (1-6) and four known metabolites (7-10). The new structures were elucidated by spectroscopic analysis, and their absolute configurations were determined by electronic circular dichroism calculations. Compounds 1 and 3-6 represent the first examples of ethylidene-bridged dimers from the building blocks 4H-chromene-4,7(8H)-dione and α-pyrone, and 2 is a unique homodimer of spiciferone. Compounds 1, 2, and 5-9 significantly inhibited the growth of weed-like dicot Arabidopsis thaliana at 100.0 µM. Notably, 8 showed the strongest inhibitory activity against the fresh weight and root elongation of A. thaliana with the IC50 values of 32.04 and 26.78 µM, respectively, whereas 1, 8, and 9 stimulated the growth of A. thaliana at lower concentrations. Meanwhile, compounds 2 and 6 exhibited weak inhibitory effects on the root elongation of monocot rice, while 1 and 8 exhibited growth-promoting effects on the shoot and root elongation of rice in a roughly dose-dependent manner.


Assuntos
Arabidopsis , Ascomicetos , Pironas/química , Benzopiranos/farmacologia , Benzopiranos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Ascomicetos/química , Estrutura Molecular
9.
Angew Chem Int Ed Engl ; 62(15): e202300773, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36806846

RESUMO

Tricrilactones A-H (1-8), a new family of oligomeric 10-membered macrolides featuring collectively five unique ring skeletons, were isolated from a hitherto unexplored fungus, Trichocladium crispatum. Compounds 1 and 7 contain two unconventional bridged (aza)tricyclic core skeletons, 2, 3, 5, and 6 share an undescribed tetracyclic 9/5/6/6 ring system, 4 bears an uncommon 9/5/6/10/3-fused pentacyclic architecture, and 8 is a dimer bridged by an unexpected C-C linkage. Their structures, including absolute configurations, were elucidated by spectroscopic analysis, quantum chemical calculations, and X-ray diffraction analysis. Importantly, the absolute configuration of the highly flexible side chain of 1 was resolved by the asymmetric synthesis of its four stereoisomers. The intermediate-trapping and isotope labeling experiments facilitated the proposal of the biosynthetic pathway for these macrolides. In addition, their antiosteoporosis effects were evaluated in vivo (zebrafish).


Assuntos
Chaetomium , Macrolídeos , Animais , Estrutura Molecular , Macrolídeos/química , Peixe-Zebra , Antibacterianos/farmacologia
10.
Microbiol Spectr ; 11(1): e0276422, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36622153

RESUMO

The prevalence of superbugs, represented by methicillin-resistant Staphylococcus aureus (MRSA), has become a serious clinical and public safety concern with rising incidence in hospitals. Polyketides with diverse chemical structures harbor many antimicrobial activities, including those of rifampin and rapamycin against MRSA. Streptomyces sp. QHH-9511 was isolated from a niche habitat in the Qinghai-Tibet Plateau and used to produce antibacterial metabolites. Herein, an integrated approach combining genome mining and metabolic analysis were employed to decipher the chemical origin of the antibacterial components with pigmented properties in strain QHH-9511, a novel Streptomyces species from a lichen symbiont on the Qinghai-Tibet Plateau. Genomic phylogeny assembled at the chromosome level revealed its unique evolutionary state. Further genome mining uncovered 36 candidate gene clusters, most of which were uncharacterized. Meanwhile, based on liquid chromatography coupled to diode array detection mass spectrometry, a series of granaticins, BSMs, chromones, phaeochromycins, and related molecules were discovered by using the Global Natural Product Social molecular networking platform. Subsequently, several pigment compounds were isolated and identified by high-resolution mass spectrometry and/or nuclear magnetic resonance, among which the structure-activity relationships of seven aromatic polyketides showed that the fused lactone ring of the C-2 carboxyl group could increase antibacterial activity. Genetic experiments indicated that all seven aromatic polyketides are a series of metabolic shunts produced by a single type II polyketide synthase (PKS) cluster. Comparative genomic analysis of granaticin producers showed that the granaticin gene cluster is widely distributed. This study provides an efficient method to combine genome mining and metabolic profiling techniques to uncover bioactive metabolites derived from specific habitats, while deepening our understanding of aromatic polyketide biosynthesis. IMPORTANCE Undescribed microorganisms from special habitats are being screened for anti-superbug drug molecules. In a project to screen actinomycetes for anti-MRSA activity, we isolated a Streptomyces strain from Qinghai Lake lichens. The phylogeny based on the genome assembled at the chromosome level revealed this strain's unique evolutionary state. The chemical origins of the antibacterial components with pigment properties in strain QHH-9511 were determined using an integrated approach combining genome mining and metabolic analysis. Further genome mining uncovered 36 secondary metabolite gene clusters, the majority of which were previously unknown. A series of aromatic compounds were discovered using molecular network analysis, separation, and extraction. Genetic experiments revealed that all seven aromatic polyketides are a series of metabolic shunts produced by a single cluster of type II PKSs. This study describes a method for identifying novel Streptomyces from specific habitats by combining genome mining with metabolic profiling techniques.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Policetídeos , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/metabolismo , Tibet , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Policetídeos/química , Policetídeos/metabolismo , Genômica , Filogenia
11.
Sci Total Environ ; 863: 160970, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36539091

RESUMO

Ecosystems provide benefits to human well-being, but highly concentrated human activities also cause environmental pressure. Previous studies focused only on one aspect: either ecosystem services (ESs) or ecosystem damage (ED). To provide comprehensive view of ecosystem status in the selected study area, an integrated ecosystem performance analytic framework was established based on the ED-ESs synergistic effect. This study quantitatively analyzed the dynamic variation in ecosystem status from both ED and ESs perspectives with a case study of Jinan City, China, from 2000 to 2020. The results showed that the environmental and economic impacts caused by pollution were 692.87 species.year and $15.58 × 108 in 2020, respectively, and they were mainly derived from energy consumption. Regarding ESs, three regulating services (water retention, soil retention, and carbon sequestration) increased from south to north, whereas material services presented the opposite trend. Ecosystem service value had declined after peaking in 2010 when material services contributed the most. Overall, the Jinan City suffered from ecosystem decline, with ecosystem performance on a downward trend from 2000 to 2020. Finally, the characterization factors of four ESs were appropriately incorporated into the life cycle impact assessment to drive the evolution in ecosystem performance calculations.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Conservação dos Recursos Naturais/métodos , Solo , Cidades , China
12.
Environ Dev Sustain ; : 1-19, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35645607

RESUMO

As a significant protein source for humans and animals, soybean (Glycine max) has experienced a fast growth with the rapid development of population and economy. Despite broad interest in energy consumption and CO2 emissions generated by soybean production, there are few impact-oriented water footprint assessments of soybean production. This study evaluates the fossil energy, carbon, and water footprints of China's soybean production so that key environmental impacts can be identified. To provide reliable results for decision-making, uncertainty analysis is conducted based on the Monte Carlo model. Results show that the impact on climate change, ecosystem quality, human health, and resources is 3.33 × 103 kg CO2 eq (GSD2 = 1.87), 6.18 × 10-5 Species·yr (GSD2 = 1.81), 3.26 × 10-3 Disability-adjusted Life Years (GSD2 = 1.81), and 81.51 $ (GSD2 = 2.28), respectively. Freshwater ecotoxicity is the dominant contributor (77.69%) to the ecosystem quality category, while climate change (85.22%) is the dominant contributor to the human health category. Key factors analysis results show that diammonium phosphate and diesel, and on-site emissions, are the major contributors to the overall environmental burden of soybean production. Several policy recommendations are proposed, focusing on trade structure optimization, efficient resource use, and technological improvements. Such policy recommendations provide valuable insights to those decision-makers so that they can prepare appropriate mitigation policies.

13.
J Environ Manage ; 312: 114949, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35367689

RESUMO

Nickel is a critical metal for global low-carbon energy transition, but its production processes require massive energy inputs and emit large amounts of pollutants. This study constructed life cycle inventories of the mainstream electrolytic nickel production chains in China at the industrial level and subsequently evaluated their environmental performance via a regionalised life cycle impact assessment method. Results show that environmental indicator results of the electrolytic nickel production from the leaching electrowinning method were 17.7%-40.2% lower than those from the grind and flotation electrolytic method. At the endpoint level, the nickel mining and beneficiation stages contributed 54.7%-65.91% of human health damage, 83.0%-84.7% of ecosystem quality damage and 80.8%-83.7% of resources damage. The key processes, including direct processes, cement input and energy consumption (e.g., electricity and coal), accounted for more than 62.1% of the impacts in the key midpoint categories. The potential environmental damage of China's nickel mining and beneficiation industry increased by 29.2% from 2010 to 2018 because of the growing trend of nickel ore demand. In the case that China's nickel metal recovery rate reaches the global average level, then approximately 3.83 × 102 Daly of human health damage, 59.83 Species·year of ecosystem quality damage and 1.64 × 108 $ of resources damage can be avoided annually. Strategies for promoting the full assimilation of renewable electricity, applying the clinker-free cemented backfill materials in the mining process, precious recovery by bioleaching from tailings and reusing waste rock as building materials are recommended. Meanwhile, extended producer responsibility should to be comprehensively implemented in the nickel-related industries to alleviate the environmental implications and nickel supply pressures from geo-mining.


Assuntos
Ecossistema , Níquel , Animais , China , Carvão Mineral/análise , Humanos , Estágios do Ciclo de Vida , Mineração
14.
Phytochemistry ; 193: 112981, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34653910

RESUMO

In this research, twenty aromatic and branched aliphatic polyketides, including seven previously undescribed butenolide derivatives, piterriones A-G and one known analogue, along with twelve known altenusin derivatives, were isolated from the isopod-associated fungus Pidoplitchkoviella terricola. Their structures were elucidated by analysis of NMR (1D and 2D) and mass spectrometry data, and their absolute configurations were determined by Mosher's method, microscale derivatization, and comparison of their specific rotations and ECD spectra. Dihydroaltenuene B exhibited mushroom tyrosinase inhibitory activity with an IC50 value of 38.33 ± 1.59 µM, which was comparable to that of the positive control, kojic acid (IC50 = 39.72 ± 1.34 µM). A molecular-docking study disclosed the hydrogen bonding interactions between the 3-OH and 4'-OH of dihydroaltenuene B and the His244, Met280 and Gly281 residues of tyrosinase.


Assuntos
Ascomicetos , Isópodes , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Animais , Estrutura Molecular
15.
J Environ Manage ; 305: 114378, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34959058

RESUMO

The application potential and environmental benefits of ground source heat pump (GSHP) systems have become the focal points of decarbonization in the building sector. Synchronized and scientific analysis of GSHP systems' environmental and economic performance, however, remains lacking. This study analyzes the application prospects of GSHP systems via a life cycle assessment-based life cycle costing method, and considers China's actual status quo. The internal and external annual costs of a GSHP system per square meter are $ 4.05 and $ 1.37, respectively. Electricity generation and steel production are key processes to improve the environmental performance of a GSHP system further. Compared with coal-based heating, a GSHP system can mitigate 65%-95% of the environmental impact and 85% of external costs, except for the metal depletion impact which is 1.5 times higher than that of coal-based heating. In Shandong Province, promoting GSHP systems can substitute up to 69.4% of the district heating area, which implies reductions in fossil depletion, greenhouse gas emissions, human health impact, ecosystem quality impact, and external costs by up to 2.37 × 1010 kg oil eq, 1.08 × 1011 kg CO2 eq, 3.87 × 105 DALY, 1.18 × 103 Species. year, and $ 2.51 × 1010, respectively. In consideration of environmental and economic aspects, a GSHP system can exhibit benefits compared with coal-based heating after 2.34 years of operation. To improve the economic and environmental performance of GSHP systems, a series of recommendations on financial subsidies, renewable energy development, inter-regional power transmission, steel scrap utilization, and hydrogen reduction steelmaking is provided.


Assuntos
Ecossistema , Temperatura Alta , China , Carvão Mineral , Humanos , Energia Renovável
16.
J Agric Food Chem ; 69(23): 6524-6534, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34096711

RESUMO

Sixteen metabolites, including seven C7-alkylated salicylaldehyde derivatives (1-7) and nine prenylated indole alkaloids (8-16), three of which are new, namely, asperglaucins A and B (1 and 2) and neoechinulin F (8), were separated from the endolichenic fungus Aspergillus chevalieri SQ-8. Asperglaucin A (1) represents an unusual phthalide-like derivative with a benzo[c]thiophen-1(3H)-one scaffold. All compounds were assessed in vitro for antibacterial, antineuroinflammatory, and antioxidant activities. Notably, asperglaucins A and B exhibited potent antibacterial activities against two plant pathogens Pseudomonas syringae pv actinidae (Psa) and Bacillus cereus, with an MIC value of 6.25 µM; further SEM analyses illustrated that the possible bacteriostatic mechanisms for compounds 1 and 2 were to alter the external structure of B. cereus and Psa, and to cause the rupture or deformation of the cell membranes, respectively, and the results suggest that compounds 1 and 2 may serve as potential promising candidates for lead compounds of agrochemical bactericides. Furthermore, compounds 6 and 10 significantly inhibited nitric oxide production with an IC50 value of ca. 12 µM, and the possible anti-inflammatory mechanisms involved were also studied by molecular docking. Finally, the tested phenolics 3-5 showed significant antioxidative effects. Thus, strain SQ-8 represents a novel resource of these bioactive metabolites to be utilized.


Assuntos
Fungos , Alcaloides Indólicos , Aldeídos , Aspergillus , Alcaloides Indólicos/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular
17.
Nat Prod Bioprospect ; 11(3): 325-332, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33963522

RESUMO

Two new sterpurane sesquiterpenoids named sterpurol D (1) and sterpurol E (2), and one skeletally new sesquiterpene, cryptomaraone (3), bearing a 5,6-fused bicyclic ring system, along with five known ones, sterpurol A (4), sterpurol B (5), paneolilludinic Acid (6), murolane-2α, 9ß-diol-3-ene (7) and (-)-10,11-dihydroxyfarnesol (8) were isolated from an endolichenic fungus Cryptomarasmius aucubae. The structures of the new compounds were elucidated by analysis of NMR spectroscopic spectra and HRESIMS data. The absolute configurations of 1 and 2 were established by spectroscopic data analysis and comparison of specific optical rotation, as well as the biosynthetic consideration. Additionally, compounds 1, 2, 4-6, and 8 showed significant nitric oxide (NO) production inhibition in Lipopolysaccharide (LPS)-induced BV-2 microglial cells with the IC50 values ranging from 9.06 to 14.81 µM.

18.
J Environ Manage ; 287: 112359, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33756212

RESUMO

As the largest consumer of rapeseed oil in the world, China should consider the environmental effect of rapeseed oil production. However, only a few improvement measures have been proposed. To fill this gap, this study analyzed the energy, carbon and water footprints of rapeseed oil production based on the International Organization for Standardization standards using the framework of life cycle assessment. Results show that most of the energy, carbon, and water footprint of rapeseed oil production can be contributed to the direct processes of rapeseed cultivation, and the indirect processes of transport and fertilizer/diesel production. The value of energy and carbon footprints are calculated as 726.07 kg oil eq and 3889.75 kg CO2 eq, respectively. For the water footprint, the values of acidification, aquatic eutrophication, carcinogens, freshwater ecotoxicity, water scarcity, and non-carcinogens are 14.24 kg SO2 eq, 4.53 kg PO4-3 eq, 6.72 × 10-5Case, 5.43 × 104 PAF.m3.d, 437.62 m3 deprived, and 1.88 × 10-5 case, respectively. Spatial analysis shows that the total environmental impacts of rapeseed production are concentrated in Sichuan, Hunan, Hubei, and Jiangxi Provinces. Correlation analysis reveals the positive correlation of human health and ecosystem quality with fertilizer application and pesticide loss. In general, the environmental effect can be effectively reduced by adjusting the industrial layout to shorten the distance of transport, improve the fine cultivation degree in low-yield areas, and decrease the use of pesticides in the hilly region of southern China.


Assuntos
Carbono , Água , Pegada de Carbono , China , Ecossistema , Humanos , Óleo de Brassica napus
19.
Sci Total Environ ; 752: 141963, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889291

RESUMO

Nowadays, agricultural production places an enormous burden on freshwater resources, and the environmental external cost caused by the restoration of water quality degradation has attracted great attention. Maize is regarded as one of the world's major food security crops, and China is the second-largest maize producer. Thus, this study conducts an impact-oriented water footprint coupled economic impact assessment to quantify the water-related environmental impacts and economic burden caused by China's maize production from 2008 to 2017. Results show that the overall damage to human health and ecosystem quality of China's maize production in 2017 were 4.32 × 104 DALY and 4.62 × 103 Species·yr, respectively. The total economic cost was $ 2.15 × 1011, which included an internal cost of $ 5.99 × 1010 and external cost of $ 1.55 × 1011. Key factor analysis demonstrates that diesel and fertilizer production dominated the reduction in ecological and external cost burdens. Direct water consumption and labor cost played leading roles in human health and internal cost, respectively. The spatiotemporal variation assessment indicates that Inner Mongolia and Heilongjiang were the hotspots for water footprint and economic impact assessment results after considering the yield factor. The national average water footprint and economic impact caused by producing 1 ton of maize showed an upward trend from 2008 to 2015, however, a significant decline transpired later. Overall, improving the resource efficiency (i.e., diesel and freshwater), scientific application of fertilizer and reducing labor input can further lessen the water footprint and economic impact of maize production. Developing the social environment can also generate indirect environmental and economic benefits to China's maize production.

20.
Sensors (Basel) ; 20(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906755

RESUMO

In recent years, increasing image data comes from various sensors, and object detection plays a vital role in image understanding. For object detection in complex scenes, more detailed information in the image should be obtained to improve the accuracy of detection task. In this paper, we propose an object detection algorithm by jointing semantic segmentation (SSOD) for images. First, we construct a feature extraction network that integrates the hourglass structure network with the attention mechanism layer to extract and fuse multi-scale features to generate high-level features with rich semantic information. Second, the semantic segmentation task is used as an auxiliary task to allow the algorithm to perform multi-task learning. Finally, multi-scale features are used to predict the location and category of the object. The experimental results show that our algorithm substantially enhances object detection performance and consistently outperforms other three comparison algorithms, and the detection speed can reach real-time, which can be used for real-time detection.

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