RESUMO
Hybrid bermudagrass (Cynodon dactylon × C. transvaalensis) is widely used as turf in southern and transition zones of China. From June to September in 2022, an unknown disease was consistently observed on hybrid bermudagrass in different regions of Nanjing China, exhibiting distinct symptoms of leaf necrosis, severe root rot and circular or irregular necrotic patches with 20-300 cm in diameter. In this study, culture -independent and dependent methods were used to elucidate the dominant fungal pathogens associated with the disease. Basidiomycota and Marasmiellus were shown to be the dominant phyla (51.96%-70.60%) and genera (50.09%-69.84%) in the symptomatic samples. A total of 128 fungal strains were isolated from symptomatic root tissues, and 40 strains representing the largest proportion (31.25%), were identified as Marasmiellus mesosporus, based on the morphological characteristics, phylogenetic analysis of ITS and LSU rDNA region, and pathogenicity testing. Temperature sensitivity tests revealed that M. mesosporus grew well at high temperature (growth rate of 13.74 mm/d at 36 â). To our knowledge, this is the first report of M. mesosporus causing root rot disease on hybrid bermudagrass during hot summer months. The study will have important implications for the management of the disease.
RESUMO
BACKGROUND: Some species of Marine bacteria pose great risks to human and mariculture organisms. Meanwhile, Vibrio harveyi and Vibrio parahaemolyticus strains have acquired resistance to many antibiotics. OBJECTIVE: A novel series of erythromycin 9-acylhydrazone derivatives were synthesized and evaluated for their in vitro antibacterial activity against marine pathogens. METHODS: The site-selective N-acylation of erythromycin hydrazone was achieved using acid chloride/ triethylamine in methanol as the reaction system. All the synthesized target compounds were evaluated for their antibacterial activity by determination of minimum inhibitory concentrations (MICs) using the broth microdilution method. RESULTS: All the tested acylhydrazone compounds showed moderate to high activity with MIC value 0.125-1 µg/mL against Vibrio parahaemolyticus and Vibrio harveyi. CONCLUSION: The introduction of the acylhydrazone moiety at the C-9 position of erythromycin improved its activity against the above-mentioned marine bacteria strains.
Assuntos
Eritromicina , Vibrio , Humanos , Eritromicina/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
The 5-(chloromethyl)furfural (CMF) derivative ethyl 5-(chloromethyl)furan-2-carboxylate undergoes two-electron electrochemical reduction in a simple, undivided cell to give the corresponding furylogous enolate anion, which can either be quenched with carbon dioxide to give a 5-(carboxymethyl)furan-2-carboxylate or with hydrogen ion to give a 5-methylfuran-2-carboxylate, thereby expanding the derivative scope of CMF as a biobased platform molecule.
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Alfalfa (Medicago sativa L.) is an important forage in intercropping or rotation ecosystem, and shading is the principal limiting factor for its growth under the crop or forest. Agronomic studies showed that shading would systematically reduce the biomass of alfalfa. However, little is known about the reproduction of alfalfa under shading conditions. In order to study the effect of shading on the reproductive characteristics of alfalfa, two alfalfa cultivars ("Victoria" and "Eureka") were used to study the effect of shading levels (full light, 56.4% shade, and 78.7% shade) on alfalfa flowering phenology, pollen viability, stigma receptivity, and seed quality. Results showed that shading delayed flowering phenology, shortened the flowering stage, faded the flower colors, and significantly reduced pollen viability, stigma receptivity, the number of flowers, quantity, and quality of seeds. Under shading conditions, seed yield per plant was obviously positively correlated with germination potential, germination rate, pollen viability, and 1,000-seed weight. The number of flower buds, pollen viability, 1,000-seed weight, and germination rate had the greatest positive direct impact on seed yield per plant. Our findings suggested that delayed flowering and reducing reproduction growth were important strategies for alfalfa to cope with shading and pollen viability was the key bottleneck for the success of alfalfa reproduction under shading. However, given that alfalfa is a perennial vegetative-harvest forage, delaying flowering in a weak light environment was beneficial to maintain the high aboveground biomass of alfalfa. Therefore, this should be taken into account when breeding alfalfa cultivars suitable for intercropping. Future research should further reveal the genetic and molecular mechanism of delayed flowering regulating the accumulation and distribution of assimilates between vegetative and reproductive organs of alfalfa under shading, so as to provide a theoretical basis for breeding of shade-tolerant alfalfa cultivars.
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Platycodin D (PD) is the active metabolite of Platycodon grandiflorum. The main purpose of this study was to develop and evaluate a water-in-oil (W/O) microemulsion formulation of PD (PD-ME). The PD-ME was successfully prepared by the water titration method at K m = 2, to draw the pseudoternary phase diagrams. Physical characterization including the particle size, pH, refractive index, average viscosity, and polydispersity index (PDI) was performed. The in vivo characteristics were evaluated by intestinal permeability and pharmacokinetic studies. The optimized microemulsion formulation consisted of 100 mg/ml PD aqueous solution, soybean phospholipids, ethanol, and oleic acid (27:39:19:15, w/w). The average viscosity, pH, droplet size, PDI, and zeta potential of the PD-ME were 78.65 ± 0.13 cPaâ¢s, 5.70 ± 0.05, 30.46 ± 0.20 nm, 0.33 ± 0.00, and -3.13 mV, respectively. The drug concentration of the PD-ME was 26.3 ± 0.6 mg/ml. The PD-ME showed significantly higher apparent permeability coefficients than PD (p < .01). The pharmacokinetic studies showed that the PD-ME had significantly higher values of T 1/2 (2.26-fold), AUC0-24h (area under the curve; 1.65-fold), and MRT0-24h (1.58-fold) than PD (p < .01). It can be seen that W/O ME presents a strategy with great promise for enhancing the intestinal permeability and better oral absorption of drugs with high polarity and poor permeability.
Assuntos
Absorção Intestinal , Platycodon/metabolismo , Saponinas/administração & dosagem , Triterpenos/administração & dosagem , Animais , Área Sob a Curva , Emulsões , Etanol/química , Meia-Vida , Concentração de Íons de Hidrogênio , Masculino , Ácido Oleico/química , Tamanho da Partícula , Fosfolipídeos/química , Ratos , Ratos Sprague-Dawley , Saponinas/química , Saponinas/farmacocinética , Glycine max/química , Triterpenos/química , Triterpenos/farmacocinética , Viscosidade , Água/químicaRESUMO
A new, simplified method for the synthesis of dimethyl aryl acylsulfonium salts has been developed. A series of dimethyl aryl acylsulfonium bromides were prepared by the reaction of aryl methyl ketones with hydrobromic acid and dimethylsulfoxide (DMSO). This sulfonium salt confirms that bromine production and the bromination reaction take place in the DMSO-HBr oxidation system. What's more, it is also a key intermediate for the synthesis of arylglyoxals.
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Brometos/química , Cetonas/química , Brometos/síntese química , Dimetil Sulfóxido/químicaRESUMO
Copper-catalyzed direct conversion of benzylic alcohols to aryl nitriles was realized using NH3(aq.) as the nitrogen source, O2 as the oxidant and TEMPO as the co-catalyst. Furthermore, copper-catalyzed one-pot synthesis of primary aryl amides from alcohols was also achieved.
Assuntos
Amônia/química , Álcoois Benzílicos/química , Cobre/química , Nitratos/química , Nitrilas/síntese química , Catálise , Estrutura Molecular , Nitrilas/química , Oxirredução , Água/químicaRESUMO
An abundance of candidate genes have been reported as susceptibility factors for the risk of nasopharyngeal carcinoma (NPC). Vitamin D receptor (VDR) plays an important role in cellular differentiation and the control of proliferation in a variety of cell types. To our knowledge, however, no study has reported the relationship between the VDR and NPC. The purpose of this study is to explore the potential correlation between single-nucleotide polymorphisms of the VDR gene (VDR) Fok I and Bsm I and NPC. A total of 171 patients with NPC and 176 age- and sex-matched controls were involved in this study. Genotypes were determined by using polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. There were no significant differences in the genotype and allele frequencies of VDR Fok I and Bsm I polymorphisms between the group of patients with NPC and the control group in a Chinese Han population (for VDR Fok I: adjusted OR 1.03, 95% CI: 0.76-1.41; for VDR Bsm I: adjusted OR 0.80, 95% CI: 0.48-1.33). Further studies will be needed to explore the complicated gene-gene interaction and gene-environmental interactions in the susceptibility to NPC, especially in ethnically disparate populations in cohort study samples.
Assuntos
Neoplasias Nasofaríngeas/genética , Polimorfismo Genético/genética , Receptores de Calcitriol/genética , Adulto , Povo Asiático , Carcinoma , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/epidemiologiaRESUMO
Single crystals of the title compound, C(10)H(13)OS(+)·Br(-), were obtained from ethyl acetate/ethyl ether after reaction of acetophenone with hydro-bromic acid and dimethyl-sulfoxide. The carbonyl group is almost coplanar with the neighbouring phenyl ring [O-C-C-C = 178.9â (2)°]. The sulfanium group shows a trigonal-pyramidal geometry at the S atom. The crystal structure is stabil-ized by C-Hâ¯Br hydrogen-bonding inter-actions. Weak π-π inter-actions link adjacent phenyl rings [centroid-centroid distance = 3.946â (2)â Å].