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1.
Nat Commun ; 15(1): 5879, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-38997253

RESUMO

The development of new antibiotics continues to pose challenges, particularly considering the growing threat of multidrug-resistant Staphylococcus aureus. Structurally diverse natural products provide a promising source of antibiotics. Herein, we outline a concise approach for the collective asymmetric total synthesis of polycyclic xanthene myrtucommulone D and five related congeners. The strategy involves rapid assembly of the challenging benzopyrano[2,3-a]xanthene core, highly diastereoselective establishment of three contiguous stereocenters through a retro-hemiketalization/double Michael cascade reaction, and a Mitsunobu-mediated chiral resolution approach with high optical purity and broad substrate scope. Quantum mechanical calculations provide insight into stereoselective construction mechanism of the three contiguous stereocenters. Additionally, this work leads to the discovery of an antibacterial agent against both drug-sensitive and drug-resistant S. aureus. This compound operates through a unique mechanism that promotes bacterial autolysis by activating the two-component sensory histidine kinase WalK. Our research holds potential for future antibacterial drug development.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Xantenos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Xantenos/síntese química , Xantenos/farmacologia , Xantenos/química , Testes de Sensibilidade Microbiana , Estereoisomerismo , Compostos Policíclicos/síntese química , Compostos Policíclicos/farmacologia , Compostos Policíclicos/química , Descoberta de Drogas , Estrutura Molecular
2.
Sci Total Environ ; 948: 174870, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39029755

RESUMO

OBJECTIVE: Polychlorinated biphenyls (PCBs) have caused great environmental concerns. The study aims to investigate underlying molecular mechanisms between PCBs exposure and prostate cancer (PCa). METHODS: To investigate the association between PCBs exposure and prostate cancer by using CTD, TCGA, and GEO datasets. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to explore pathways associated with PCBs-related genes (PRGs). Using Lasso regression analysis, a novel PCBs-related prognostic model was developed. Both internal and external validations were conducted to assess the model's validity. Molecular docking was utilized to assess the binding capacity of PCBs to crucial genes. At last, preliminary experimental validations were conducted to confirm the biological roles of Aroclor 1254 in PCa cells. RESULTS: The GO enrichment analysis of PRGs revealed that the biological processes were most enriched in the regulation of transcription from the RNA polymerase II promoter and signal transduction. The KEGG enrichment analysis showed that of the pathways in cancer is the most significantly enriched. Next, a PCBs-related model was constructed. In the training, test, GSE70770, and GSE116918 cohorts, the biochemical recurrences free survival of the patients with high-risk scores was considerably lower. The AUCs at 5 years were 0.691, 0.718, 0.714, and 0.672 in the four cohorts, demonstrating the modest predictive ability. A nomogram that incorporated clinical characteristics was constructed. The results of the anti-cancer drug sensitivity analysis show chemotherapy might be more beneficial for patients at low risk. The molecular docking analysis demonstrated PCBs' ability to bind to crucial genes. PCa cells exposed to Aroclor 1254 at a concentration of 1 µM showed increased proliferation and invasion capabilities. CONCLUSIONS: This study provides new insights into the function of PCBs in PCa and accentuates the need for deeper exploration into the mechanistic links between PCBs exposure and PCa progression.

3.
Bioorg Chem ; 151: 107664, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39079392

RESUMO

Eleven undescribed monoterpenoid bisindole alkaloids, alstomaphyines A-K (1-11), along with three known analogues were isolated from the leaves and stem bark of the Alstonia macrophylla. Compounds 1-3 were unprecedented dimerization alkaloids incorporating a macroline-type motif with an ajmaline-type motif via a C-C linkage. Their structures and absolute configurations were elucidated by extensive spectroscopic analysis, electronic circular dichroism (ECD) calculation, and CD exciton chirality method. Compounds 1-3 displayed potential inhibitory bioactivity against AChE with IC50 values of 4.44 ± 0.35, 3.59 ± 0.18, and 3.71 ± 0.23 µM, respectively. Enzyme kinetic study revealed compounds 1-3 as mixed competitive AChE inhibitors. Besides, compounds 8 and 12-14 exhibited better cytotoxicity against human cancer cell line HT-29 than cisplatin. Flow cytometry data revealed that compounds 8, 13, and 14 significantly induced the HT-29 cells arrest in G0/G1 phase in a concentration-dependent manner.

4.
Talanta ; 279: 126621, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39079437

RESUMO

Iron-anchored nitrogen/doped carbon single-atom nanozymes (Fe-N/C), which possess homogeneous active sites and adjustable catalytic environment, represent an exemplary model for investigating the structure-function relationship and catalytic activity. However, the development of pyrolysis-free synthesis technique for Fe-N/C with adjustable enzyme-mimicking activity still presents a significant challenge. Herein, Fe-N/C anchored three carrier morphologies were created via a pyrolysis-free approach by covalent organic polymers. The peroxidase-like activity of these Fe-N/C nanozymes was regulated via the pores of the anchored carrier, resulting in varying electron transfer efficiency due to disparities in contact efficacy between substrates and catalytic sites within diverse microenvironments. Additionally, a colorimetric sensor array for identifying antioxidants was developed: (1) the Fe-N/C catalytically oxidized two substrates TMB and ABTS, respectively; (2) the development of a colorimetric sensor array utilizing oxTMB and oxABTS as sensing channels enabled accurate discrimination of antioxidants such as ascorbic acid (AsA), glutathione (GSH), cysteine (Cys), gallic acid (GA), and caffeic acid (CA). Subsequently, the sensor array underwent rigorous testing to validate its performance, including assessment of antioxidant mixtures and individual antioxidants at varying concentrations, as well as target antioxidants and interfering substances. In general, the present study offered valuable insights into the active origin and rational design of nanozyme materials, and highlighting their potential applications in food analysis.

5.
Neurochem Res ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002091

RESUMO

Alzheimer's disease (AD) represents the most widespread neurodegenerative disorder, distinguished by a gradual onset and slow progression, presenting a substantial challenge to global public health. The mitochondrial-associated membrane (MAMs) functions as a crucial center for signal transduction and material transport between mitochondria and the endoplasmic reticulum, playing a pivotal role in various pathological mechanisms of AD. The dysregulation of mitochondrial quality control systems is considered a fundamental factor in the development of AD, leading to mitochondrial dysfunction and subsequent neurodegenerative events. Recent studies have emphasized the role of MAMs in regulating mitochondrial quality control. This review will delve into the molecular mechanisms underlying the imbalance in mitochondrial quality control in AD and provide a comprehensive overview of the role of MAMs in regulating mitochondrial quality control.

6.
Huan Jing Ke Xue ; 45(6): 3523-3532, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897772

RESUMO

In this study, the effects of four types of amendments on effective Cd and Cd content in different parts of prickly ash soil and soil enzyme activity were studied, which provided scientific basis for acidification improvement of purple soil and heavy metal pollution control. A field experiment was conducted. Six treatments were set up:no fertilizer (CK), only chemical fertilizer (F), lime + chemical fertilizer (SF), organic fertilizer + chemical fertilizer (OM), biochar + chemical fertilizer (BF), and vinasse biomass ash + chemical fertilizer (JZ). Soil pH; available Cd (DTPA-Cd); Cd content in branches, leaves, shells, and seeds of Zanthoxylum; as well as the activities of catalase (S-CAT), acid phosphatase (S-ACP), and urease (S-UE) in different treatments were studied, and their relationships were clarified. The results showed following:① The two treatments of vinasse biomass ash + chemical fertilizer and lime + chemical fertilizer significantly increased soil pH (P < 0.05) to 3.39 and 2.25 units higher than that in the control, respectively. Compared with that in the control treatment, the content of available Cd in soil under vinasse biomass ash + chemical fertilizer and lime + chemical fertilizer treatment decreased by 28.91 % and 20.90 %, respectively. ② The contents of Cd in leaves, shells, and seeds of Zanthoxylum were decreased by 31.33 %, 30.24 %, and 34.01 %, respectively. The Cd enrichment ability of different parts of Zanthoxylum was different, with the specific performances being leaves > branches > seeds > shells. Compared with that of the control, the enrichment coefficient of each part of Zanthoxylum treated with vinasse biomass ash + chemical fertilizer decreased significantly(P < 0.05)by 27.54 %-40.0 %. ③ The changes in catalase and urease activities in soil treated with amendments were similar. Compared with those in the control group, the above two enzyme activities were significantly increased by 191.26 % and 199.50 %, respectively, whereas the acid phosphatase activities were decreased by 16.45 %. Correlation analysis showed that soil available Cd content was significantly negatively correlated with soil pH value(P < 0.01), S-CAT and S-UE enzyme activities were significantly positively correlated with soil pH(P < 0.01), and the soil available Cd content was significantly negatively correlated (P < 0.01); the S-ACP enzyme showed the complete opposite trends. The application of lime and vinasse biomass ash to acidic purple soil had the most significant effect on neutralizing soil acidity. It was an effective measure to improve acidic purple soil and prevent heavy metal pollution by reducing the effective Cd content in soil and improving the soil environment while inhibiting the absorption and transfer of Cd in various parts of Zanthoxylum.


Assuntos
Cádmio , Fertilizantes , Poluentes do Solo , Solo , Poluentes do Solo/metabolismo , Cádmio/metabolismo , Solo/química , Urease/metabolismo , Zanthoxylum/química , Zanthoxylum/metabolismo , Fosfatase Ácida/metabolismo , Catalase/metabolismo , Disponibilidade Biológica , Óxidos/química , Compostos de Cálcio/química , Carvão Vegetal/química
7.
J Hazard Mater ; 474: 134829, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38865924

RESUMO

Selective catalytic oxidation of the hazardous DMF exhaust gas presents a significant challenge in balancing oxidation activity and products selectivity (CO, NOx, N2, etc.). It is found that Cu/H-MOR demonstrates superior performance for DMF oxidation compared to CuO on other supports (γ-Al2O3, HY, ZSM-5) in terms of product selectivity and stability. The geometric and electronic structures of CuO active sites in Cu/H-MOR have been regulated by CeO2 promoter, leading to an increase in the ratio of active CuO (highly dispersed CuO and Cu+ specie). As a result, the oxidation activity and stability of the Cu/H-MOR catalyst were enhanced for DMF selective catalytic oxidation. However, excessive CuO or CeO2 content led to decreased N2 selectivity due to over-high oxidation activity. It is also revealed that Ce3+ species, active CuO species, and surface acid sites play a critical role in internal selective catalytic reduction reaction during DMF oxidation. The 10Cu-Ce/H-MOR (1/4) catalyst exhibited both high oxidation activity and internal selective catalytic reduction activity due to its abundance of active CuO specie as well as Ce3+ species and surface acid sites. Consequently, the 10Cu-Ce/H-MOR (1/4) catalyst demonstrated the widest temperature window for DMF oxidation with high N2 selectivity. These findings emphasize the importance of surface active sites modification for DMF selective catalytic oxidation.

8.
Food Sci Nutr ; 12(6): 4110-4121, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873490

RESUMO

Among middle-aged and older people, balanced and nutritious diets are the foundation for maintaining bone health and preventing osteoporosis. This study is aimed at investigating the link between dietary folic acid intake and the risk of osteoporosis among middle-aged and older people. A total of 20,686 people from the National Health and Nutritional Examination Survey (NHANES) 2007-2010 are screened and included, and 5312 people aged ≥45 years with integral data are ultimately enrolled in evaluation. Demographics and dietary intake-related data are gathered and analyzed, and the odds ratio (OR) and 95% confidence interval (CI) of each tertile category of dietary folic acid intake and each unit increase in folic acid are assessed via multivariate logistic regression models. On this basis, the receiver operating characteristic (ROC) curve is used to identify the optimal cutoff value of dietary folic acid intake for indicating the risk of osteoporosis. Of 5312 people with a mean age of 62.4 ± 11.0 years old, a total of 513 people with osteoporosis are screened, and the dietary folic acid intake amount of the osteoporosis group is significantly lower than that of the non-osteoporosis group (p < .001). The lowest tertile category is then used to act as a reference category, and a higher dietary folic acid intake amount is observed to be positively related to lower odds for risk of osteoporosis. This trend is also not changed in adjustments for combinations of different covariates (p all < .05). Based on this, a dietary folic acid intake of 475.5 µg/day is identified as an optimal cutoff value for revealing osteoporosis. Collectively, this nationwide population-based study reveals that a higher daily dietary folic acid intake has potential protective effects on osteoporosis in middle-aged and older people.

9.
Bioorg Chem ; 150: 107536, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38878751

RESUMO

Carboxylesterase 1 (CES1), a member of the serine hydrolase superfamily, is involved in a wide range of xenobiotic and endogenous substances metabolic reactions in mammals. The inhibition of CES1 could not only alter the metabolism and disposition of related drugs, but also be benefit for treatment of metabolic disorders, such as obesity and fatty liver disease. In the present study, we aim to develop potential inhibitors of CES1 and reveal the preferred inhibitor structure from a series of synthetic pyrazolones (compounds 1-27). By in vitro high-throughput screening method, we found compounds 25 and 27 had non-competitive inhibition on CES1-mediated N-alkylated d-luciferin methyl ester (NLMe) hydrolysis, while compound 26 competitively inhibited CES1-mediated NLMe hydrolysis. Additionally, Compounds 25, 26 and 27 can inhibit CES1-mediated fluorescent probe hydrolysis in live HepG2 cells with effect. Besides, compounds 25, 26 and 27 could effectively inhibit the accumulation of lipid droplets in mouse adipocytes cells. These data not only provided study basis for the design of newly CES1 inhibitors. The present study not only provided the basis for the development of lead compounds for novel CES1 inhibitors with better performance, but also offered a new direction for the explore of candidate compounds for the treatment of hyperlipidemia and related diseases.


Assuntos
Adipócitos , Hidrolases de Éster Carboxílico , Inibidores Enzimáticos , Pirazolonas , Humanos , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipócitos/citologia , Animais , Camundongos , Pirazolonas/farmacologia , Pirazolonas/química , Pirazolonas/síntese química , Relação Estrutura-Atividade , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Estrutura Molecular , Células Hep G2 , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células 3T3-L1
10.
Phytochemistry ; 225: 114165, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38815884

RESUMO

Ten C-geranylated flavonoids, along with three known analogues, were isolated from the leaves of Artocarpus communis. The chemical structures of these compounds were unambiguously determined via comprehensive spectroscopic analysis, single-crystal X-ray diffraction experiments, and quantum chemical electronic circular dichroism calculations. Structurally, artocarones A-I (1-9) represent a group of unusual, highly modified C-geranylated flavonoids, in which the geranyl chain is cyclised with the ortho-hydroxy group of flavonoids to form various heterocyclic scaffolds. Notably, artocarones E and G-I (5 and 7-9) feature a 6H-benzo[c]chromene core that is hitherto undescribed in C-geranylated flavonoids. Artocarone J (10) is the first example of C-9-C-16 connected C-geranylated aurone. Meanwhile, the plausible biosynthetic pathways for these rare C-geranylated flavonoids were also proposed. Notably, compounds 1, 2, 4, 8, 11, and 12 exhibited promising in vitro inhibitory activities against respiratory syncytial virus and herpes simplex virus type 1.


Assuntos
Antivirais , Artocarpus , Flavonoides , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Artocarpus/química , Antivirais/química , Antivirais/farmacologia , Antivirais/isolamento & purificação , Estrutura Molecular , Herpesvirus Humano 1/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Folhas de Planta/química , Relação Estrutura-Atividade , Modelos Moleculares
11.
PLoS One ; 19(5): e0302148, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38771887

RESUMO

This paper extracts culture element of long-term orientation from Chinese listed firm's annual report, then argue and testify whether long-term orientation can help firms to hang on risky decision especially as innovation, when firms are under performance pressure. There are three main conclusions. First, we report that the higher degree of long-term oriented culture a firm has, the stronger innovation capability the firm shows. Second, we find that long-term oriented culture can improve employee's educational qualification to promote corporate innovation, as well as improve the corporate internal control to promote innovation. Third, when firms are subjected to internal or external performance pressure in their business process, higher long-term oriented culture will make firms more innovative.


Assuntos
Cultura Organizacional , Inovação Organizacional , China , Humanos , Comércio
12.
Aging Clin Exp Res ; 36(1): 104, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713318

RESUMO

INTRODUCTION: Studies examining the effects of social participation on activities of daily living (ADL) disability are still scarce. AIM: To assess the reciprocal relationship between ADL disability trajectories and social participation among older Chinese people aged ≥ 60 years. METHODS: This study included 2976 participants aged ≥ 60 years in six waves of a community-based survey from 2015 to 2022. Basic activities of daily living (BADL) and instrumental activities of daily living (IADL) were used to assess the ADL disability in each survey. Social participation was assessed by involvement in four social activities and an extensive social participation score. Group-based trajectory modeling was used to identify potential heterogeneity in longitudinal changes over 7 years and explore associations between baseline predictors of group membership and these trajectories. RESULTS: Two BADL disability trajectories were identified: stable (94.8%) and increase (5.2%). Additionally, three IADL disability trajectories were distinguished: stable (73.2%), moderate (20.2%), and increase (6.6%). After controlling for the potential covariates, each point increase in the extensive social participation score correlated with a 17% decrease in the odds of older individuals belonging to the increase BADL trajectory group (OR = 0.83, 95% CI = 0.68-1.00). For IADL, it decreased the odds of being assigned to the moderate trajectory group by 16% (OR = 0.84, 95% CI = 0.75-0.95) and to the increase trajectory group by 23% (OR = 0.77, 95% CI = 0.64-0.93). CONCLUSIONS: Higher levels of social participation among older individuals were more likely to be classified as stable trajectories in both BADL and IADL. Increased participation in social activities by community-dwelling elderly adults may promote healthy aging.


Assuntos
Atividades Cotidianas , Pessoas com Deficiência , Vida Independente , Participação Social , Humanos , Idoso , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Longitudinais , Idoso de 80 Anos ou mais , Estudos de Coortes , China
13.
Huan Jing Ke Xue ; 45(5): 3027-3036, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629563

RESUMO

Biochar and modified biochar have been widely used as remediation materials in heavy metal-contaminated agricultural soils. In order to explore economical and effective materials for the remediation of cadmium (Cd)-contaminated acidic purple soil, distillers 'grains were converted into distillers' grains biochar (DGBC) and modified using nano-titanium dioxide (Nano-TiO2) to produce two types of modified DGBCs:TiO2/DGBC and Fe-TiO2/DGBC. A rice pot experiment was used to investigate the effects of different biochar types and application rates (1%, 3%, and 5%) on soil properties, nutrient content, Cd bioavailability, Cd forms, rice growth, and Cd accumulation. The results showed that:① DGBC application significantly increased soil pH, cation exchange capacity (CEC), and nutrient content, with TiO2/DGBC and Fe-TiO2/DGBC exhibiting better effects. ② DGBC and modified DGBCs transformed Cd from soluble to insoluble forms, increasing residual Cd by 1.22% to 18.46% compared to that in the control. Cd bioavailability in soil decreased significantly, with available cadmium being reduced by 11.81% to 23.67% for DGBC, 7.64% to 43.85% for TiO2/DGBC, and 19.75% to 55.82% for Fe-TiO2/DGBC. ③ DGBC and modified DGBCs increased rice grain yield, with the highest yields observed at a 3% application rate:30.60 g·pot-1 for DGBC, 37.85 g·pot-1 for TiO2/DGBC, and 39.10 g·pot-1 for Fe-TiO2/DGBC, representing 1.13, 1.40, and 1.44 times the control yield, respectively. Cd content in rice was significantly reduced, with grain Cd content ranging from 0.24 to 0.30 mg·kg-1 for DGBC, 0.16 to 0.26 mg·kg-1 for TiO2/DGBC, and 0.14 to 0.24 mg·kg-1 for Fe-TiO2/DGBC. Notably, Cd content in rice grains fell below the food safety limit of 0.2 mg·kg-1 (GB2762-2022) at 5% for TiO2/DGBC and 3% and 5% for Fe-TiO2/DGBC. In conclusion, Nano-TiO2 modified DGBC effectively reduced the bioavailability of soil Cd through its own adsorption and influence on soil Cd forms distribution, thus reducing the absorption of Cd by rice and simultaneously promoting rice growth and improving rice yield. It is a type of Cd-contaminated soil remediation material with a potential application prospect. The results can provide scientific basis for farmland restoration and agricultural safety production of Cd-contaminated acidic purple soil.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Oryza/química , Solo/química , Poluentes do Solo/análise , Carvão Vegetal/química , Grão Comestível/química
14.
Fitoterapia ; 175: 105982, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685512

RESUMO

A phytochemical investigation on the buds of edible medicinal plant, Eugenia carvophyllata, led to the discovery of seven new compounds, caryophones A-G (1-7), along with two biogenetically-related known ones, 2-methoxy-7-methyl-1,4-naphthalenedione (8) and eugenol (9). Compounds 1-3 represent the first examples of C-5-C-1' connected naphthoquinone-monoterpene adducts with a new carbon skeleton. Compounds 4-7 are a class of novel neolignans with unusual linkage patterns, in which the C-9 position of one phenylpropene unit coupled with the aromatic core of another phenylpropene unit. The chemical structures of the new compounds were determined based on extensive spectroscopic analysis, X-ray diffraction crystallography, and quantum-chemical calculation. Among the isolates, compounds (-)-2, 3, 6, and 9 showed significant in vitro inhibitory activities against respiratory syncytial virus (RSV)-induced nitric oxide (NO) production in RAW264.7 cells.


Assuntos
Anti-Inflamatórios , Eugenia , Lignanas , Naftoquinonas , Óxido Nítrico , Compostos Fitoquímicos , Camundongos , Células RAW 264.7 , Animais , Óxido Nítrico/metabolismo , Estrutura Molecular , Lignanas/farmacologia , Lignanas/isolamento & purificação , Lignanas/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/química , Naftoquinonas/farmacologia , Naftoquinonas/isolamento & purificação , Naftoquinonas/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Eugenia/química , Vírus Sinciciais Respiratórios/efeitos dos fármacos , China
17.
Zhongguo Zhong Yao Za Zhi ; 49(3): 728-734, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621876

RESUMO

Mesona chinensis is a common medicinal and edible plant in the Lingnan region of China, which has extensive pharmacological activity. However, the study of its chemical constituents is not sufficient. In this study, a variety of modern chromatographic separation techniques were used to isolate two compounds from 95% ethanol extract of the grass parts of M. chinensis. Their absolute configurations were determined by ultraviolet spectroscopy(UV), infrared spectroscopy(IR), high resolution mass spectrometry(HR-ESI-MS), 1D and 2D nuclear magnetic resonance(1D NMR and 2D NMR), and single-crystal X-ray diffraction(SC-XRD). Specifically, they were two new benzoyl-sesquiterpenes and named mesonanol A and mesonanol B, respectively. The results of the pharmacological activity evaluation showed that neither of the two new compounds showed obvious antiviral and anti-inflammatory activities.


Assuntos
Lamiaceae , Sesquiterpenos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho , Estrutura Molecular
18.
Plant Physiol Biochem ; 208: 108523, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38492487

RESUMO

The development of pollen is critical to male reproduction in flowering plants. Acyl-CoA synthetase (ACOS) genes play conserved functions in regulating pollen development in various plants. Our previous work found that knockout of the SlACOS1 gene in tomato might decrease fruit setting. The current study further revealed that SlACOS1 was important to pollen development and male fertility. The SlACOS1 gene was preferentially expressed in the stamen of the flower with the highest expression at the tetrad stage of anther development. Mutation of the SlACOS1 gene by the CRISPR/Cas9-editing system reduced pollen number and viability as well as fruit setting. The tapetum layer exhibited premature degradation and the pollen showed abnormal development appearing irregular, shriveled, or anucleate in Slacos1 mutants at the tetrad stage. The fatty acid metabolism in anthers was significantly impacted by mutation of the SlACOS1 gene. Furthermore, targeted fatty acids profiling using GC-MS found that contents of most fatty acids except C18:1 and C18:2 were reduced. Yeast complementation assay demonstrated that the substrate preferences of SlACOS1 were C16:0 and C18:0 fatty acids. Male fertility of Slacos1 mutant could be slightly restored by applying exogenous palmitic acid, a type of C16:0 fatty acid. Taken together, SlACOS1 played important roles on pollen development and male fertility by regulating the fatty acid metabolism and the development of tapetum and tetrad. Our findings will facilitate unraveling the mechanism of pollen development and male fertility in tomato.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen , Flores/metabolismo , Fertilidade/genética , Ácidos Graxos , Ligases/metabolismo , Regulação da Expressão Gênica de Plantas
19.
Yeast ; 41(3): 108-127, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38450805

RESUMO

Schizosaccharomyces japonicus Yukawa et Maki (1931) and Schizosaccharomyces versatilis Wickerham et Duprat (1945) have been treated as varieties of S. japonicus or as conspecific, based on various approaches including mating trials and nDNA/nDNA optical reassociation studies. However, the type strains of S. japonicus and S. versatilis differ by five substitutions (99.15% identity) and one 1-bp indel in the sequences of the D1/D2 domain of the 26S rRNA gene, and 23 substitutions (96.3% identity) and 31-bp indels in the sequences of internal transcribed spacer (ITS) of rRNA, suggesting that they may not be conspecific. To reassess their taxonomic status, we conducted mating trials and whole-genome analyses. Mating trials using the type strains showed a strong but incomplete prezygotic sterility barrier, yielding interspecies mating products at two orders of magnitude lower efficiency than intraspecies matings. These mating products, which were exclusively allodiploid hybrids, were unable to undergo the haplontic life cycle of the parents. We generated chromosome-level gap-less genome assemblies for both type strains. Whole genome sequences yielded an average nucleotide identity (ANI) of 86.4%, indicating clear separation of S. japonicus and S. versatilis. Based on these findings, we propose the reinstatement of S. versatilis as a distinct species (holotype strain: CBS 103T and ex-types: NRRL Y-1026, NBRC 1607, ATCC 9987, PYCC 7100; Mycobank no.: 847838).


Assuntos
Schizosaccharomyces , Schizosaccharomyces/genética , Filogenia , Análise de Sequência de DNA
20.
Huan Jing Ke Xue ; 45(3): 1655-1664, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471877

RESUMO

The aim of this study was to explore the effects of four amendments on soil fertility and labile carbon fraction characteristics of acid purple soil, so as to provide scientific basis for nutrient management and carbon storage stability in purple soil. Field experiments were carried out, and six treatments were set up:no fertilization (CK), only chemical fertilizer (F), lime + chemical fertilizer (SF), organic fertilizer + chemical fertilizer (OM), biochar + chemical fertilizer (BF), and vinasse biomass ash + chemical fertilizer (JZ). The contents of soil organic matter, pH, available nutrients, soil integrated fertility index (IFI), dissolved organic carbon (DOC), microbial biomass carbon (MBC), particulate organic carbon (POC), their effective rates, and soil carbon pool management index (CPMI) under different treatments were studied to clarify their relationships. The results showed that:① the application of amendments significantly increased soil pH and the contents of organic matter, alkali-hydrolyzed nitrogen, available phosphorus, and available potassium (P<0.05). The OM and JZ treatments had the most significant increase in soil comprehensive fertility index (P<0.05), with increases of 1.96 and 0.77 and 170.43% and 66.96%, respectively. ② Compared with those in the control treatment, the contents of POC, MBC, and DOC in JZ and OM increased by 110.30% and 84.81%, 61.08% and 46.56%, and 195.87% and 141.67%, respectively. The application of amendments significantly increased the soil carbon pool index (CPI) and CMPI (P<0.05), in which the OM treatment showed the most significant increase, with soil CPI and CMPI values increasing by 107.34% and 90.75% compared with those of the control, respectively. ③ Soil organic carbon and its labile fractions were positively correlated with IFI (P<0.05), and redundancy analysis showed that there were significant differences among different treatments. The interpretation rates of soil IFI, pH, and available potassium to organic carbon and its components reached significant levels, and the order of interpretation rates was IFI(74.6%)>pH (11.7%)>AK(6.5%). The application of vinasse biomass ash and organic fertilizer to acid purple soil had the most significant effect on improving soil fertility and soil quality and was conducive to promoting the accumulation and activation of soil carbon fractions.

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