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1.
Molecules ; 29(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893321

RESUMO

Owing to the important role of and increasing demand for lithium resources, lithium extraction is crucial. The use of molecular extractants is a promising strategy for selective lithium recovery, in which the interaction between lithium and the designed extractant can be manipulated at the molecular level. Herein, we demonstrate that anion receptors of tripodal hexaureas can selectively extract Li2SO4 solids into water containing DMSO (0.8% water) compared to other alkali metal sulfates. The hexaurea receptor with terminal hexyl chains displays the best Li+ extraction selectivity at 2-fold over Na+ and 12.5-fold over K+. The driving force underpinning selective lithium extraction is due to the combined interactions of Li+-SO42- electrostatics and the ion-dipole interaction of the lithium-receptor (carbonyl groups and N atoms); the latter was found to be cation size dependent, as supported by computational calculations. This work indicates that anion binding receptors could drive selective cation extraction, thus providing new insights into the design of receptors for ion recognition and separation.

2.
Angew Chem Int Ed Engl ; 62(51): e202314510, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37926915

RESUMO

The phosphate-coordination triple helicates A2 L3 (A=anion) with azobenzene-spaced bis-bis(urea) ligands (L) have proven to undergo a rare in situ photoisomerization (without disassembly of the structure) rather than the typically known, stepwise "disassembly-isomerization-reassembly" process. This is enabled by the structural self-adaptability of the "aniono" assembly arising from multiple relatively weak and flexible hydrogen bonds between the phosphate anion and bis(urea) units. Notably, the Z→E thermal relaxation rate of the isomerized azobenzene unit is significantly decreased (up to 20-fold) for the triple helicates compared to the free ligands. Moreover, the binding of chiral guest cations inside the cavity of the Z-isomerized triple helicate can induce optically pure diastereomers, thus demonstrating a new strategy for making light-activated chiroptical materials.

3.
Int J Syst Evol Microbiol ; 72(12)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36748480

RESUMO

A novel Gram-stain-positive, endophytic actinobacterium, designated strain HDS5T, was isolated from leaves of Eucommia ulmoides Oliv. collected from Changde City, Hunan Province, PR China. Strain HDS5T produced yellowish oil green substrate mycelia on Gause's synthetic medium, which also carried yellowish oil green aerial hyphae, fragmenting into rod-shaped elements with smooth surfaces. Strain HDS5T grew at pH 5.0-11.0 (optimum, pH 7), at 20-40 °C (optimum, 28 °C) and in the presence of 0-8.0% NaCl (w/v; optimum, 0-1.0 %). Whole-cell hydrolysates contained meso-diaminopimelic acid as the diagnostic amino acid and no diagnostic sugars. The predominant fatty acids were iso-C16:0 and C18 : 1 ω9c. The menaquinones were MK-10(H2), MK-10(H4) and MK-10(H6). Strain HDS5T showed high 16S rRNA gene sequence similarity to Nocardiopsis prasina DSM 43845T (99.72 %), Nocardiopsis ganjiahuensis DSM 45031T (99.31 %), Nocardiopsis exhalans JCM 11759T (99.17 %), Nocardiopsis alba DSM 43377T (99.11 %), Nocardiopsis metallicus KBS6T (99.11 %), Nocardiopsis valliformis DSM 45023T (99.04 %), Nocardiopsis listeri NBRC 13360T (98.97 %), Nocardiopsis lucentensis DSM 44048T (98.83 %), Nocardiopsis terrae YIM 90022T (98.83 %) and <98.7 % similarities to other type strains. Phylogenetic analysis of 16S rRNA gene sequences and whole-genome sequences showed that strain HDS5T was closely related to N. prasina DSM 43845T. However, the average nucleotide identity based on blast and digital DNA-DNA hybridization values between them were determined to be 90.1 and 40.9 %, respectively, below the threshold of 95-96 and 70 % for the delineation of prokaryotic genomic species, suggesting that strain HDS5T represents a novel Nocardiopsis species. Furthermore, the morphological and physio-biochemical characteristics were sufficient to distinguish strain HDS5T from N. prasina DSM 43845T. Consequently, based on phenotypic and genotypic characteristics, strain HDS5T represents a new Nocardiopsis species, for which the name Nocardiopsis eucommiae sp. nov. is proposed. The type strain is HDS5T (=MCCC 1K06172T=JCM 34707T).


Assuntos
Actinobacteria , Actinomycetales , Eucommiaceae , Nocardia , Ácidos Graxos/química , Eucommiaceae/genética , Nocardiopsis , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Nocardia/genética , Vitamina K 2/química , Fosfolipídeos/química
4.
Antonie Van Leeuwenhoek ; 115(10): 1297-1305, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36006529

RESUMO

A novel actinomycete strain, designated as MG28T, was isolated from rhizosphere soil of Akebia trifoliate. The taxonomic position of the strain was investigated by using a polyphasic approach. BLAST search of the full-length 16S rRNA gene sequence of strain MG28T indicated it represented a member of the genus Streptomyces, and displayed 99.03%, 98.90%, 98.90%, 98.89%, 98.83% and less than 98.70% sequence similarities with S. phaeolivaceus GY16T, S. deccanensis KCTC 19241T, S. europaeiscabiei KACC 20186T, S. fructofermentans CGMCC 4.1593T, S. scabiei NRRL B-16523T and other species of the genus Streptomyces with validly published names, respectively. Phylogenomic analysis indicated that strain MG28T was closely related to Streptomyces deccanensis KCTC 19241T. However, the average nucleotide identity values and the digital DNA-DNA hybridization values between them indicated that strain MG28T represented a distinct species. Furthermore, strain MG28T was also distinctly differentiated from strain KCTC 19241T by morphological, physiological and biochemical characteristics. Therefore, strain MG28T (= MCCC 1K06895T = JCM 34922T) represents a novel species of the genus Streptomyces, for which the name Streptomyces akebiae sp. nov. is proposed.


Assuntos
Actinobacteria , Streptomyces , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos , Nucleotídeos , Filogenia , RNA Ribossômico 16S/genética , Ranunculales , Rizosfera , Análise de Sequência de DNA , Solo , Microbiologia do Solo
5.
Ecotoxicol Environ Saf ; 238: 113561, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35489292

RESUMO

Zearalenone (ZEA) is a nonsteroidal estrogenic mycotoxin, which mainly contaminates grains and has estrogen-like effects on the reproductive system. Betulinic acid (BA), a natural lupane-type pentacyclic triterpene, has anti-oxidative and anti-inflammatory properties. This study aimed to investigate whether BA alleviates ZEA-induced testicular damage and explore the possible mechanism. Here, BA ameliorated testicular damage by mitigating the disordered arrangement of seminiferous tubules, the exfoliation of lumen cells, and the increase of cell apoptosis caused by ZEA. Meanwhile, BA alleviated ZEA-triggered testicular damage by restoring hormone levels and sperm motility, and reconstructing the blood-testis-barrier. Moreover, BA alleviated ZEA-exposed testicular oxidative stress by activating Nrf2 pathway. Furthermore, BA moderated ZEA-evoked testicular inflammation by inhibiting p38/ERK MAPK pathway. Overall, our results revealed that BA has a therapeutic protective effect on ZEA-induced testicular injury and oxidative stress via p38/ERK MAPK inhibition and Nrf2-mediated antioxidant defense activation, which provides a viable alternative to alleviate ZEA-induced male reproductive toxicology.


Assuntos
Sistema de Sinalização das MAP Quinases , Fator 2 Relacionado a NF-E2 , Triterpenos Pentacíclicos , Testículo , Zearalenona , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Triterpenos Pentacíclicos/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Zearalenona/toxicidade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ácido Betulínico
6.
Mitochondrial DNA B Resour ; 7(7): 1237-1239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837502

RESUMO

Gomesa flexuosa (Lodd) M.W.Chase & N.H.Williams is a new species of orchid revised in 2009. In this study, the chloroplast genome of G. flexuosa was sequenced to determine its genomic characteristics and phylogenetic relationship with other related species. G. flexuosa has a chloroplast genome size of 147,764 bp, comprising 25,757 bp of two inverted repeat (IR) regions, 83,579 bp of large single-copy (LSC) region, and 12,671 bp of small single-copy (SSC) region. Moreover, the whole genome contains 73 protein-coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic analysis showed that G. flexuosa is closely related to Oncidium sphacelatum.

7.
Sci Total Environ ; 776: 145837, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33639465

RESUMO

Agricultural ecological environment conservation is a major strategic mission for the sustainable development of China's agriculture and rural areas at present. Therefore, it is of great significance to examine the coupling and coordination relationship between new urbanization and the agro-ecological environment, and, accordingly, to establish China's sustainable agro-economic development model. However, this topic has not been adequately addressed in previous studies. To fill this gap, this study detailed an empirical investigation into the spatio-temporal differentiation of and influencing factors on the coupling and coordinated development of new urbanization and the agricultural ecological environment in China. First, aided by spatial analysis methods, a detailed analysis of the spatio-temporal patterns and dynamics of the coupling and coordinated development of new urbanization and the agro-ecological environment was conducted. The driving factors were quantitatively examined using the random panel Tobit model and the panel data modeling technique. The results indicate that the coupling degree between China's new urbanization and the agro-ecological environment ranges from 0.30 to 0.50, which is in the antagonistic stage. The degree of coupling and coordination is between 0.39 and 0.59, basically on the verge of imbalance and reluctant coordination. Most provinces lag behind in new urbanization. Panel data analysis demonstrates financial support for agriculture, rural economic development, environmental pollution control capabilities, and government capabilities significantly impacting the degree of coupling and coordination between China's new urbanization and the agro-ecological environment. Among them, financial support for agriculture and industrialization has different effects on the degree of coupling and coordination between the eastern and midwestern regions. Based on the findings of this study, a series of policy suggestions for improving China's new urbanization and agro-ecological environment is proposed.

8.
Antioxidants (Basel) ; 10(2)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499152

RESUMO

T-2 toxin, which is mainly produced by specific strains of Fusarium in nature, can induce immunotoxicity and oxidative stress, resulting in immune organ dysfunction and apoptosis. Betulinic acid (BA), a pentacyclic triterpenoids from nature plants, has been demonstrated to possess immunomodulating and antioxidative bioactivities. The purpose of the study was to explore the effect of BA on T-2 toxin-challenged spleen oxidative damage and further elucidate the underlying mechanism. We found that BA not only ameliorated the contents of serum total cholesterol (TC) and triglyceride (TG) but also restored the number of lymphocytes in T-2 toxin-induced mice. BA dose-dependently reduced the accumulation of reactive oxygen species (ROS), enhanced superoxide dismutase (SOD) activity, and decreased malondialdehyde (MDA) content, as well as increased the total antioxidant capacity (T-AOC) in the spleen of T-2-toxin-exposed mice. Moreover, BA reduced inflammatory cell infiltration in the spleen, improved the morphology of mitochondria and enriched the number of organelles in splenocytes, and dramatically attenuated T-2 toxin-triggered splenocyte apoptosis. Furthermore, administration of BA alleviated the protein phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinases (ERK); decreased the protein expression of kelch-like erythroid cell-derived protein with CNC homology [ECH]-associated protein1 (Keap1); and increased the protein expression of nuclear factor erythroid 2 [NF-E2]-related factor (Nrf2) and heme oxygenase-1 (HO-1) in the spleen. These findings demonstrate that BA defends against spleen oxidative damage associated with T-2 toxin injection by decreasing ROS accumulation and activating the Nrf2 signaling pathway, as well as inhibiting the mitogen-activated protein kinase (MAPK) signaling pathway.

9.
Int Immunopharmacol ; 101(Pt B): 108210, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34628148

RESUMO

Betulinic acid (BA) is a pentacyclic triterpenoid compound with potential antioxidant and anti-inflammatory effects. In this study, T-2 toxin was injected intraperitoneally in mice to establish kidney damage model and to evaluate the protective effects of BA and further reveal the molecular mechanism. BA pretreatment inhibited the T-2 toxin-stimulated increase in serum Crea, but showed no significant effect on serum Urea. BA pretreatment alleviated excessive glomerular hemorrhage and inflammatory cell infiltration in kidneys caused by T-2 toxin. Moreover, pretreatment with BA mitigated T-2 toxin-induced renal oxidative damage by up-regulating the activities of SOD and CAT, and the content of GSH, while down-regulating the accumulation of ROS and MDA. Meanwhile, BA pretreatment markedly attenuated T-2 toxin-induced renal inflammatory response by decreasing the mRNA expression of IL-1ß, TNF-α and IL-10, and increasing IL-6 mRNA expression. Furthermore, mechanism research found that pretreatment with BA could activate Nrf2 signaling pathway. It was suggested that BA ameliorated the oxidative stress and inflammatory response of T-2 toxin-triggered renal damage by activating the Nrf2 signaling pathway.


Assuntos
Inflamação/induzido quimicamente , Nefropatias/induzido quimicamente , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Triterpenos Pentacíclicos/farmacologia , Toxina T-2/toxicidade , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/tratamento farmacológico , Nefropatias/patologia , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/genética , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Ácido Betulínico
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