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1.
J Am Chem Soc ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264180

RESUMO

α-Aminonitriles are not only broadly useful building blocks but also structural motifs in bioactive molecules. The Strecker reaction is one of the most widely used methods for α-aminonitrile synthesis. However, a severe drawback in Strecker reactions is the required use of a stoichiometric amount of toxic cyanation reagents. Thus, the development of a greener and widely applicable method for the synthesis of aminonitriles from readily available starting materials presents an important yet unmet challenge. We developed a general and new method for the synthesis of aminonitriles from readily available aminoacetonitrile. This method utilized off-the-shelf ammonium salts as catalysts, tolerated air and moisture, and avoided the use of cyanation reagents, which rendered it a greener alternative to the widely practiced Strecker reaction approach. We further illustrated that chiral ammonium-catalyzed asymmetric reactions of N-arylidene aminoacetonitriles could provide chiral α-tertiary and α-quaternary aminonitriles and α-aminonitriles bearing two continuous stereocenters.

2.
Front Plant Sci ; 15: 1435927, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39148625

RESUMO

Introduction: Phosphorus nutrition and hormone concentration both affect crop yield formation. Ascertaining the interaction of phosphorus and GA3 has a synergistic effect on the grain yield and phosphorus utilization efficiency of oilseed flax in dryland. It is extremely important for improving grain yield and phosphorus utilization efficiency. Methods: A field experiment was conducted in 2019 and 2020 at the Dingxi Oil Crops Test Station to investigated the effects of phosphorus, gibberellin (GA3), and their interaction on the grain yield and phosphorus-utilization efficiency of oilseed flax plants. Phosphorus fertilizer was applied at three levels (0, 67.5, 135 kg P2O5·ha-1) and GA3 was also sprayed at three concentrations (0, 15, and 30 mg·L-1). Results: The results showed that application of 67.5 kg P2O5·ha-1 reduced leaves acid phosphatase (ACPase) activity, but increased phosphorus accumulation throughout the growth period, the 1000-kernel weight (TKW), and the number of grains per capsule. Spraying GA3 significantly increased the leaves ACPase activity, phosphorus accumulation after anthesis and its contribution to grain, phosphorus-utilization efficiency, the number of capsules per plant, and TKW. The phosphorus accumulation at the anthesis, kernel, and maturity stages under the treatment of fertilizing 67.5 kg P2O5·ha-1 and spraying 30 mg·L-1 GA3 were increased by 56.06%, 73.51%, and 62.17%, respectively, compared with the control (no phosphorus, no GA3). And the phosphorus accumulation after anthesis and its contribution to grain also increased. 67.5 kg P2O5·ha-1 combined with 30 mg·L-1 GA3 and 135 kg P2O5·ha-1 combined with 15 mg·L-1 GA3 both significantly increased grain yield of oilseed flax, reaching 1696 kg·ha-1 and 1716 kg·ha-1 across two years, respectively. And there was no significant difference between them. However, the former treatment significant increased the apparent utilization rate, agronomic utilization rate, and partial productivity of phosphorus. The interaction between phosphorus and GA3 was significant for grain yield. Conclusion: Therefore, the application of 67.5 kg P2O5·ha-1 in combination with 30 mg·L-1 GA3 is an effective fertilization approach for enhancing oilseed flax growth and grain yield in the experiment region and other similar areas.

3.
Environ Sci Pollut Res Int ; 31(39): 51364-51380, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39110285

RESUMO

Heat stress (HS) causes severe economic losses in sheep industry worldwide. The objective of the present study was to investigate the effects of a herbal formula (HF) supplement on growth, digestibility, antioxidant capacity, and rumen microbes in fattening lambs under HS. The HF composed of four herbs was prepared based on the theory of compatibility of Chinese medicine "Jun-Chen-Zuo-Shi". Two-hundred forty 3-month weaned lambs (initial weight 36.61 ± 0.73 kg) were randomly allocated into four groups, supplemented 0% (Control), 0.5%, 1.0%, and 1.5% HF in diets. All lambs were exposed to HS conditions with 79.7 of average temperature-humidity index throughout an experimental period of 35 days. Growth performance, apparent digestibility, and antioxidant activities, involving antioxidant enzymes and heat shock proteins (HSPs), were measured at the end of trial, as well as microbial communities in bacteria and archaea. Results showed that 0.5% HF increased (P = 0.02) average daily gain by 13.80% and decreased feed-to-gain ratio (P = 0.03) by 14.68%, compared to control. With increasing HF doses, the digestibility of ether extract and acid detergent fiber demonstrated a cubical (P < 0.01) and quadratic (P = 0.03) relation, respectively; moreover, glutathione peroxidase and catalase activities demonstrated a quadratic increase (P < 0.01). Serum levels of HSP60, HSP70, and HSP90 for 0.5% HF were lower than that in control (P < 0.05). On the other hand, total volatile fatty acid, acetic acid, butyric acid, valeric acid, and isovaleric acid levels exhibited quadratic increases (P ≤ 0.01) with HF doses. From rumen microbes, the abundance and diversity of bacterial community were improved by HF supplements. Particularly for 0.5% HF group, the operational taxonomic units were the greatest among all groups. Compared to control, Prevotella abundance for HF supplements from 0.5 to 1.5% increased by 35.57 to 60.15%, and Succiniclasticum abundance demonstrated a quadratic pattern (P = 0.02) with doses. Additionally, Methanosphaera abundance in archaeal community raised by 0.2 to 3.3-folds when lambs were fed the HF additions of 0.5 to 1.5%. In summary, dietary HF supplements would contribute to alleviating HS in lambs, and our results suggest the optimal dose of 0.5% HF supplement in diet.


Assuntos
Ração Animal , Antioxidantes , Rúmen , Animais , Ovinos , Antioxidantes/metabolismo , Rúmen/microbiologia , Dieta/veterinária , Digestão/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Suplementos Nutricionais , Microbiota/efeitos dos fármacos
4.
ACS Nano ; 18(22): 14640-14649, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38761149

RESUMO

The control of reaction selectivity is of great interest in chemistry and depends crucially on the revelation of key influencing factors. Based on well-defined molecule-substrate model systems, various influencing factors have been elucidated, focusing primarily on the molecular precursors and the underlying substrates themselves, while interfacial properties have recently been shown to be essential as well. However, the influence of molecular chemisorption direction on reaction selectivity, as a subtle interplay between molecules and underlying substrates, remains elusive. In this work, by a combination of scanning tunneling microscopy imaging and density functional theory calculations, we report the influence of molecular chemisorption direction on the reaction selectivity of two types of dehalogenative coupling on Au(111), i.e., polymerization and cyclization, at the atomic level. The diffusion step of a reactive dehalogenated intermediate in two different chemisorption directions was theoretically revealed to be the key to determining the corresponding reaction selectivity. Our results highlight the important role of molecular chemisorption directions in regulating the on-surface dehalogenative coupling reaction pathways and products, which provides fundamental insights into the control of reaction selectivity by exploiting some subtle interfacial parameters in on-surface reactions for the fabrication of target low-dimensional carbon nanostructures.

5.
Mycology ; 15(1): 85-90, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558838

RESUMO

Invasive aspergillosis (IA) is the most severe type of Aspergillus infection. Yunnan has developed agriculture, and the proportion of triazole-resistant A. fumigatus induced by triazole fungicides is much higher than that in other regions of China. Inhalation of triazole-resistant A. fumigatus is one of the main factors inducing IA. We gathered five strains of A. fumigatus from the sputum or bronchoalveolar lavage fluid (BALF) of patients with IA in Yunnan. Subsequent testing showed that all of these strains were resistant to triazoles and harboured mutations in the tandem repeat sequence of the cyp51A promoter region, suggesting that they may be triazole-resistant A. fumigatus present in the environment.

6.
Front Plant Sci ; 15: 1257882, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567136

RESUMO

Introduction: An appropriate supply of ammonium (NH4+) in addition to nitrate (NO3-) can greatly improve plant growth and promote maize productivity. However, knowledge gaps exist regarding the mechanisms by which different nitrogen (N) fertilizer sources affect the enzymatic activity of nitrogen metabolism and non-structural carbohydrates during the post-anthesis period. Methods: A field experiment across 3-year was carried out to explore the effects of four nitrateammonium ratio (NO3-/NH4+ = 1:0 (N1), 1:1 (N2), 1:3 (N3), and 3:1 (N4)) on postanthesis dry matter (DM) and N accumulation, partitioning, transportation, and grain yield in maize. Results: NO3-/NH4+ ratio with 3:1 improved the enzymatic activity of N metabolism and non-structural carbohydrate accumulation, which strongly promoted the transfer of DM and N in vegetative organs to reproductive organs and improved the pre-anthesis DM and nitrogen translocation efficiency. The enzymatic activities of nitrate reductase, nitrite reductase, glutamine synthetase, glutamine oxoglutarate aminotransferase, and non-structural carbohydrate accumulation under N4 treatment were increased by 9.30%-32.82%, 13.19%-37.94%, 4.11%-16.00%, 11.19%-30.82%, and 14.89%-31.71% compared with the other treatments. Mixed NO3--N and NH4+-N increased the total DM accumulation at the anthesis and maturity stages, simultaneously decreasing the DM partitioning of stem, increasing total DM, DM translocation efficiency (DMtE), and contribution of pre-anthesis assimilates to the grain (CAPG) in 2015 and 2017, promoting the transfer of DM from stem to grain. Furthermore, the grain yield increased by 3.31%-9.94% (2015), 68.6%-26.30% (2016), and 8.292%-36.08% (2017) under the N4 treatment compared to the N1, N2, and N3 treatments. Conclusion: The study showed that a NO3-/NH4+ ratio of 3:1 is recommended for high-yield and sustainable maize management strategies in Northwestern China.

7.
J Am Chem Soc ; 146(18): 12329-12337, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38662599

RESUMO

Chiral aminonitriles not only are broadly useful building blocks but also increasingly appear as structural motifs in bioactive molecules and pharmaceuticals. The catalytic asymmetric synthesis of chiral aminonitriles, therefore, has been intensively investigated, as reflected in numerous reports of catalytic asymmetric Strecker reactions. Despite such great progress, the catalytic asymmetric synthesis of chiral α,α-dialkyl aminonitriles in a highly selective and efficient manner is still a formidable challenge. Here, we report a new approach for the catalytic asymmetric synthesis of chiral α,α-dialkyl aminonitriles via reaction of cyanoketimines with enals. We demonstrate that this reaction could be carried out with as low as 20 ppm catalyst loading.

8.
ACS Nano ; 18(12): 9082-9091, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466951

RESUMO

On-surface dehalogenative reactions have been promising in the construction of nanostructures with diverse morphologies and intriguing electronic properties, while halogen (X), as the main byproduct, often impedes the formation of extended nanostructures and property characterization, and the reaction usually requires high C-X activation temperatures, especially on relatively inert Au(111). Enormous efforts in precursor design, halogen-to-halide conversion, and the introduction of extrinsic metal atoms have been devoted to either eliminating dissociated halogens or reducing reaction barriers. However, it is still challenging to separate halogens from molecular systems while facilitating C-X activation under mild conditions. Herein, a versatile halogen separation strategy has been developed based on the introduction of extrinsic sodium (Na) into dehalogenative reactions on Au(111) as model systems that both isolates the dissociated halogens and facilitates the C-Br activation under mild conditions. Moreover, the combination of scanning tunneling microscopy imaging and density functional theory calculations reveals the formation of sodium halides (NaX) from halogens in these separation processes as well as the reduction in reaction temperatures and barriers, demonstrating the versatility of extrinsic sodium as an effective "cleaner" and "dehalogenator" of surface halogens. Our study demonstrates a valuable strategy to facilitate the on-surface dehalogenative reactions, which will assist in the precise fabrication of low-dimensional carbon nanostructures.

10.
J Am Chem Soc ; 146(13): 9356-9364, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38502531

RESUMO

Pharmaceuticals and biologically active natural products usually contain multiple stereocenters. The development of catalytic asymmetric reactions for the direct construction of complex motifs containing three nonadjacent stereocenters is a particularly important and formidable challenge. In this paper, we report an unprecedented method for the direct asymmetric construction of complex chiral amines with 1,3,5- or 1,3,4-stereocenters from readily available achiral and racemic starting materials. The reaction was made possible by the development of highly efficient chiral ammonium catalysts that serve three distinct functions: promoting efficient kinetic resolution by chiral recognition of racemic electrophiles, promoting asymmetric C-C bond forming reactions by recognizing enantiotropic faces of achiral nucleophiles, and mediating a highly stereoselective protonation of carbanions. Using these trifunctional catalysts, the reaction of imines and tulipane derivatives proceeded in a highly regio-, chemo-, and stereoselective manner to produce synthetically useful yields of complex chiral amines. We believe that trifunctional catalysis can be applied in a variety of asymmetric transformations for the streamlined asymmetric synthesis of complex chiral molecules with multiple stereocenters.

11.
J Sci Food Agric ; 104(2): 818-828, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37683050

RESUMO

BACKGROUND: Lima bean protein isolate (LPI) is an underutilized plant protein. Similar to other plant proteins, it may display poor emulsification properties. In order to improve its emulsifying properties, one effective approach is using protein and polysaccharide mixtures. This work investigated the structural and emulsifying properties of LPI as well as the development of an LPI/xanthan gum (XG)-stabilized oil-in-water emulsion. RESULTS: The highest protein solubility (84.14%) of LPI was observed and the molecular weights (Mw ) of most LPI subunits were less than 35 kDa. The enhanced emulsifying activity index (15.97 m2 g-1 ) of LPI might be associated with its relatively high protein solubility and more low-Mw subunits (Mw < 35 kDa). The effects of oil volume fraction (ϕ) on droplet size, microstructure, rheological behavior and stability of emulsions were investigated. As ϕ increased from 0.2 to 0.8, the emulsion was arranged from spherical and dispersed oil droplets to polyhedral packing of oil droplets adjacent to each other, while the LPI/XG mixtures changed from particles (in the uncrowded interfacial layer) to lamellae (in the crowded interfacial layer). When ϕ was 0.6, the emulsion was in a transitional state with the coexistence of particles and lamellar structures on the oil droplet surface. The LPI/XG-stabilized emulsions with ϕ values of 0.6-0.8 showed the highest stability during a 14-day storage period. CONCLUSION: This study developed a promising plant-based protein resource, LPI, and demonstrates potential application of LPI/XG as an emulsifying stabilizer in foods. © 2023 Society of Chemical Industry.


Assuntos
Phaseolus , Proteínas de Plantas , Emulsões/química , Proteínas de Plantas/química , Polissacarídeos Bacterianos/química , Água/química
12.
J Phys Chem Lett ; 14(48): 10819-10824, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38016081

RESUMO

On-surface dehalogenative coupling reactions are promising for constructing nanostructures with diverse properties and functionalities. Extensive efforts have been devoted to single aryl-halogen (C-X) substituents and substitutions at various functionalization sites (typically including meta- and para-substitutions) to generate aryl-aryl single bonds. Moreover, multiple C-X substituents at the ortho-site and the peri- and bay-regions have been applied to create a variety of ring scaffolds. However, for multiple C-X substituents, the hierarchy of aryl-metal bond formation and dissociation remains elusive. Herein, by combining scanning tunneling microscopy imaging and density functional theory calculations, we have visualized and demonstrated the hierarchical evolution of aryl-metal bonding in organometallic intermediates involved in a dehalogenative coupling reaction on Ag(111), using a molecular precursor with both para-substitution and potential bay-region substitution. Our results elucidate how metal atoms are progressively embedded into and removed from organometallic intermediates, enhancing the understanding of on-surface dehalogenative coupling reactions for the controlled construction of the desired nanostructures.

13.
J Am Chem Soc ; 145(41): 22366-22373, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37769215

RESUMO

Understanding and controlling molecular orientations in self-assembled organic nanostructures are crucial to the development of advanced functional nanodevices. Scanning tunneling microscopy (STM) provides a powerful toolbox to recognize molecular orientations and to induce orientation changes on surfaces at the single-molecule level. Enormous effort has been devoted to directly controlling the molecular orientations of isolated single molecules in free space. However, revealing and further controlling molecular orientation selectivity in constrained environments remain elusive. In this study, by a combination of STM imaging/manipulations and density functional theory calculations, we report the orientation selectivity of tetrapyridyl-substituted porphyrins in response to various local molecular environments in artificially constructed molecular "Klotski puzzles" on Au(111). With the assistance of STM lateral manipulations, "sliding-block" molecules were able to enter predefined positions, and specific molecular orientations were adopted to fit the local molecular environments, in which the intermolecular interaction was revealed to be the key to achieving the eventual molecular orientation selectivity. Our results demonstrate the essential role of local molecular environments in directing single-molecule orientations, which would shed light on the design of molecular structures to control preferred orientations for further applications in molecular nanodevices.

14.
Altern Ther Health Med ; 29(2): 271-281, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36350320

RESUMO

Objective: Our aim was to perform a meta-analysis to compare the therapeutic effects of compound Xuanju capsules combined with hormone therapy vs hormone therapy alone in polycystic ovary syndrome (PCOS)-related infertility. Methods: Electronic databases including PubMed, The Cochrane Library, Web of Science, Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), Wanfang Data and VIP database were manually searched. The quality of included studies was evaluated based on Cochrane Systematic Review standards, and the valid data were extracted for meta-analysis using RevMan 5.3 software (Cochrane Review). Results: A total of 14 randomized controlled trials (RCTs) including 1249 patients were included in the study. Meta-analysis showed that patients in the compound Xuanju capsule + hormone therapy group had higher estradiol (E2) levels and overall rates of effective treatment than patients in the hormone therapy alone group. Moreover, they exhibited lower levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), as well as lower Kupperman scores, than the hormone therapy alone group. Conclusions: The combination of compound Xuanju capsules and hormone therapy is more effective than hormone therapy alone in the treatment of PCOS-related infertility. However, the quality of current studies is low, and high-quality clinical trials are warranted.


Assuntos
Medicamentos de Ervas Chinesas , Infertilidade , Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/tratamento farmacológico , Cápsulas , Medicamentos de Ervas Chinesas/uso terapêutico , Hormônios , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Front Psychol ; 13: 969209, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405117

RESUMO

Third language (L3) learners have great potential in developing creativity; however, the factors affecting L3 learners' creativity have received little attention. This study investigated the relationships between proactive personality, three different thinking patterns (i.e., growth mindset, fixed mindset, and golden mean thinking), and creativity among L3 learners. The participants were 220 Chinese students who attended an obligatory L3 course in college. The results showed that proactive personality, growth mindset, golden mean thinking, and creativity had significant intercorrelations. Moreover, the role of growth mindset and golden mean thinking as mediators of the proactive personality and creativity relation was supported, and the mediating effect of growth mindset was larger than that of golden mean thinking. However, the fixed mindset did not show a significant indirect effect on the path from proactive personality to creativity. This is the first research to treat growth mindset, fixed mindset, and golden mean thinking as mediating variables on the path from proactive personality to creativity, particularly demonstrating that golden mean thinking, which is specific to Asian students and located midway between a growth mindset and a fixed mindset, can cultivate creativity. Some suggestions for fostering creativity in L3 students were also included in this study.

16.
Front Plant Sci ; 13: 1024898, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275590

RESUMO

Crop production and water productivity may be impacted by diverse crop rotation and management practices. A field study was conducted from 2017-2020 in the Loess Plateau to evaluate the effects of crop rotation sequences on pre-planting and post-harvest soil water storage (SWS), annualized crop yield, water use, and water productivity. Crops in rotation included oil flax (Linum usitatissimum L.) (F), wheat (Triticum aestivum L.) (W), potato (Solanum tuberosum L.) (P). Twelve 4-year-cycle crop rotation treatments, along with a continuous oil flax treatment as a baseline, were included. The results showed that the average soil water content under the 0-150 cm soil layer in all treatments was increased after one rotation cycle, and the PWFW treatment achieved the highest SWC (17.1%). The average soil water storage (winter fallow season) and evapotranspiration (ETa) (growing season) under different crop rotation sequences were lower than those under continuous oil flax cropping. The ETa of FFFF increased by 28.9, 2.7, 15.3, and 28.4%, compared to average crop rotations in 2017, 2018, 2019, and 2020, respectively. Crop rotation had a significant effect on average annual yield and water use efficiency (WUE), which varied by year and rotation sequence. The crop rotations with the highest grain yield of oil flax were FFWP (2017), WFWP (2018),WPFF (2019) and FWPF (2020); the grain yield of wheat was highest when the two pre-crops (previously cultivated crops) were F-F, and potato yield was highest when the two pre-crops were W-F (except 2018). On average, the WUE of oil flax was 8.6, 38.7, 22.7, and 42.1% lower with FFFF than other diversity crop rotations in 2017, 2018, 2019, and 2020. We found that the WUE was not the largest when the grain yield of oil flax and wheat was highest. The treatments with maximum grain yield and WUE were not consistent. Our findings also revealed that wheat-potato-oil flax or potato-wheat-oil flax rotation could increase oil flax grain yields while wheat-oil flax-potato-oil flax markedly improved oil flax WUE.

17.
J Alzheimers Dis ; 90(2): 655-666, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36155514

RESUMO

BACKGROUND: Early intervention of amnestic mild cognitive impairment (aMCI) may be the most promising way for delaying or even preventing the progression to Alzheimer's disease. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that has been recognized as a promising approach for the treatment of aMCI. OBJECTIVE: In this paper, we aimed to investigate the modulating mechanism of tDCS on the core neurocognitive networks of brain. METHODS: We used repeated anodal high-definition transcranial direct current stimulation (HD-tDCS) over the left dorsolateral prefrontal cortex and assessed the effect on cognition and dynamic functional brain network in aMCI patients. We used a novel method called temporal variability to depict the characteristics of the dynamic brain functional networks. RESULTS: We found that true anodal stimulation significantly improved cognitive performance as measured by the Montreal Cognitive Assessment after simulation. Meanwhile, the Mini-Mental State Examination scores showed a clear upward trend. More importantly, we found significantly altered temporal variability of dynamic functional connectivity of regions belonging to the default mode network, central executive network, and the salience network after true anodal stimulation, indicating anodal HD-tDCS may enhance brain function by modulating the temporal variability of the brain regions. CONCLUSION: These results imply that ten days of anodal repeated HD-tDCS over the LDLPFC exerts beneficial effects on the temporal variability of the functional architecture of the brain, which may be a potential neural mechanism by which HD-tDCS enhances brain functions. Repeated HD-tDCS may have clinical uses for the intervention of brain function decline in aMCI patients.


Assuntos
Disfunção Cognitiva , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Córtex Pré-Frontal Dorsolateral , Córtex Pré-Frontal/fisiologia , Disfunção Cognitiva/terapia , Encéfalo/fisiologia
18.
Phytochemistry ; 202: 113359, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35940426

RESUMO

Ten undescribed C12 polyketide phialocetones A-J, featuring twelve-, six- and five-membered lactone moieties, were isolated from a rhizospheric soil-derived Phialocephala sp. YUD18001 associated with Gastrodia elata. Their structures were established by NMR spectroscopic analysis and HRMS, while their absolute configurations were determined by computational methods and chemical reactions. All isolated compounds were evaluated for their anti-inflammatory and cytotoxic activities. As a result, phialocetone D exhibited moderate effects against NO production in lipopolysaccharide (LPS)-induced RAW264.7 cells with an IC50 value of 14.77 µM, while phialocetone E showed cytotoxicity against HL-60 and SW480 cell lines with IC50 values of 19.04 and 10.22 µM, respectively.


Assuntos
Ascomicetos , Gastrodia , Policetídeos , Ascomicetos/metabolismo , Gastrodia/química , Gastrodia/metabolismo , Gastrodia/microbiologia , Lactonas/química , Lactonas/farmacologia , Solo
19.
RSC Adv ; 12(34): 22295-22301, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-36043060

RESUMO

Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A-E (1-5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum. Their structures were determined on the basis of comprehensive spectroscopic analyses, while the absolute configurations were elucidated by the comparison of experimental and calculated specific rotations. Meanwhile, the antimicrobial, cytotoxic, anti-inflammatory and acetylcholinesterase inhibitory activities of compounds 1-5 were also investigated.

20.
Arch Microbiol ; 204(9): 556, 2022 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-35964278

RESUMO

The 'Kyoho' grape (Vitaceae, Plantae) has large ears, plenty of flesh, and rich nutrition and is planted across a large area in China. There are few reports on this variety in winemaking, especially on the dynamic changes of fungi in the wine fermentation broth. In this study, we used the 'Kyoho' grapes as raw materials and adopted a high throughput to analyze dynamic changes in fungal species composition of the natural fermentation broth at four time points: day 1 (D1P), day 3 (D3P), day 5 (D5P), and day 15 (D15P). Changes in fungal metabolic pathways and dominant yeasts were also analyzed. A total of 78 families, 110 genera, and 137 species were detected, in the natural fermentation broth samples. Forty-nine families, 60 genera, and 72 species were found in the control check (CK). A total of 66 differential metabolic pathways were enriched; of those, 41 were up-regulated compared to CK, such as CDP-diacylglycerol biosynthesis I (PWY 5667), chitin degradation to ethanol (PWY 7118), and the super pathway of phosphatidate biosynthesis (PWY 7411). Changes in fungal metabolic pathways were in line with the dynamic changes of dominant yeast species in the whole process of fermentation. Pichia kluyveri, P. membranifaciens, and Citeromyces matritensis are the dominant species in the later stages of natural fermentation. These yeast species may play vital roles in the 'Kyoho' wine industry in the future.


Assuntos
Vitis , Vinho , Fermentação , Sucos de Frutas e Vegetais , Humanos , Vitis/microbiologia , Vinho/microbiologia , Leveduras
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