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1.
Antibiotics (Basel) ; 11(10)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36289962

RESUMO

Genome mining has become an important tool for discovering new natural products and identifying the cryptic biosynthesis gene clusters. Here, we utilized the flavin-dependent halogenase GedL as the probe in combination with characteristic halogen isotope patterns to mine new halogenated secondary metabolites from our in-house fungal database. As a result, two pairs of atropisomers, pestalachlorides A1a (1a)/A1b (1b) and A2a (2a)/A2b (2b), along with known compounds pestalachloride A (3) and SB87-H (4), were identified from Pestalotiopsis rhododendri LF-19-12. A plausible biosynthetic assembly line for pestalachlorides involving a putative free-standing phenol flavin-dependent halogenase was proposed based on bioinformatics analysis. Pestalachlorides exhibited antibacterial activity against sensitive and drug-resistant S. aureus and E. faecium with MIC values ranging from 4 µg/mL to 32 µg/mL. This study indicates that halogenase-targeted genome mining is an efficient strategy for discovering halogenated compounds and their corresponding halogenases.

2.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296584

RESUMO

Graphite anodes are well established for commercial use in lithium-ion battery systems. However, the limited capacity of graphite limits the further development of lithium-ion batteries. Hard carbon obtained from biomass is a highly promising anode material, with the advantage of enriched microcrystalline structure characteristics for better lithium storage. Tannin, a secondary product of metabolism during plant growth, has a rich source on earth. But the mechanism of hard carbon obtained from its derivation in lithium-ion batteries has been little studied. This paper successfully applied the hard carbon obtained from tannin as anode and illustrated the relationship between its structure and lithium storage performance. Meanwhile, to further enhance the performance, graphene oxide is skillfully compounded. The contact with the electrolyte and the charge transfer capability are effectively enhanced, then the capacity of PVP-HC is 255.5 mAh g-1 after 200 cycles at a current density of 400 mA g-1, with a capacity retention rate of 91.25%. The present work lays the foundation and opens up ideas for the application of biomass-derived hard carbon in lithium anodes.


Assuntos
Grafite , Lítio , Lítio/química , Grafite/química , Carbono/química , Taninos , Eletrodos , Íons/química , Eletrólitos
3.
Neoplasia ; 33: 100835, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36113195

RESUMO

Peptidylarginine deiminase 4 (PAD4), a Ca2+-dependent enzyme, catalyzes the conversion of arginine to citrulline and has been strongly associated with many malignant tumors. However, the molecular mechanisms of PAD4 in the development and progression of colorectal cancer (CRC) remain unclearly defined. In our study, PAD4 expression was increased in CRC tissues and cells, and was closely related to tumor size, lymph node metastasis. Moreover, the transcription factor KLF9 directly bound to PADI4 gene promoter, leading to overexpression of PAD4 in CRC cells, which augmented cell growth and migration. We revealed that PAD4 interacted with and citrullinated glycogen synthase kinase-3ß (GSK3ß) in CRC cells, and GSK3ß Arg-344 was the dominating PAD4-citrullination site. Furthermore, IgL2 and catalytic domains of PAD4 directly bound to the kinase domain of GSK3ß in CRC cells. Mechanistically, PAD4 promoted the transport of GSK3ß from the cytoplasm to the nucleus, thereby increasing the ubiquitin-dependent proteasome degradation of nuclear cyclin-dependent kinase inhibitor 1 (CDKN1A). Our study is the first to reveal the details of a critical PAD4/GSK3ß/CDKN1A signaling axis for CRC progression, and provides evidence that PAD4 is a potential diagnosis biomarker and therapeutic target in CRC.


Assuntos
Citrulinação , Neoplasias Colorretais , Arginina/genética , Biomarcadores/metabolismo , Citrulina/genética , Citrulina/metabolismo , Neoplasias Colorretais/genética , Inibidor de Quinase Dependente de Ciclina p21 , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Hidrolases/genética , Hidrolases/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas/genética , Desiminases de Arginina em Proteínas/metabolismo , Fatores de Transcrição/genética , Ubiquitinas/genética
4.
Cell Death Dis ; 13(9): 827, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167685

RESUMO

Circular RNAs (circRNAs) have been reported to play essential roles in tumorigenesis and progression. This study aimed to identify dysregulated circRNAs in gastric cancer (GC) and investigate the functions and underlying mechanism of these circRNAs in GC development. Here, we identify circ_CEA, a circRNA derived from the back-splicing of CEA cell adhesion molecule 5 (CEA) gene, as a novel oncogenic driver of GC. Circ_CEA is significantly upregulated in GC tissues and cell lines. Circ_CEA knockdown suppresses GC progression, and enhances stress-induced apoptosis in vitro and in vivo. Mechanistically, circ_CEA interacts with p53 and cyclin-dependent kinases 1 (CDK1) proteins. It serves as a scaffold to enhance the association between p53 and CDK1. As a result, circ_CEA promotes CDK1-mediated p53 phosphorylation at Ser315, then decreases p53 nuclear retention and suppresses its activity, leading to the downregulation of p53 target genes associated with apoptosis. These findings suggest that circ_CEA protects GC cells from stress-induced apoptosis, via acting as a protein scaffold and interacting with p53 and CDK1 proteins. Combinational therapy of targeting circ_CEA and chemo-drug caused more cell apoptosis, decreased tumor volume and alleviated side effect induced by chemo-drug. Therefore, targeting circ_CEA might present a novel treatment strategy for GC.


Assuntos
MicroRNAs , Neoplasias Gástricas , Apoptose/genética , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , RNA Circular/genética , Neoplasias Gástricas/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
5.
Org Lett ; 24(32): 5941-5945, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35938920

RESUMO

Prenylemestrins A and B (1 and 2, respectively), two unusual epipolythiodioxopiperazines featuring a thioethanothio bridge instead of a polysulfide bridge, were isolated from the fungus Emericella sp. CPCC 400858 guided by genomic analysis. Their structures were determined by extensive spectroscopic data, NMR and ECD calculations, and X-ray diffraction analysis. A plausible biosynthetic pathway for 1 and 2 was proposed on the basis of gene cluster analysis. Prenylemestrins A and B exhibited cytotoxicities against human chronic myelocytic leukemia cell lines K562 and MEG-01.


Assuntos
Emericella , Cristalografia por Raios X , Emericella/química , Fungos , Genômica , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
6.
Cancer Lett ; 545: 215826, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35839920

RESUMO

Circular RNAs (circRNAs) are covalently closed, endogenous molecules that are widespread in eukaryotes. Recent evidence indicates that circRNAs play important roles in carcinogenesis. Several circRNAs have been reported to comprise translatable RNA; however, whether circRNAs encode functional proteins remains unknown. In our study, circRNA sequencing was carried out using five pathologically diagnosed gastric carcinoma (GC) samples and their paired adjacent normal tissues, we characterized the circRNA GSPT1 (circGSPT1), which is expressed at low levels in GC. Antibody detections, and mass spectrometry were used to validate active circRNA translation. The spanning junction open reading frame in circGSPT1, driven by an internal ribosome entry site (IRES), encodes a functional peptide, termed GSPT1-238aa. Interestingly, GSPT1-238aa tends to select the start codon used to initiate translation. This is the first finding of selective translation driven by IRES. CircGSPT1 and GSPT1-238aa halted the proliferation, migration, and invasion in GC cells in vitro. We also confirmed that the vimentin/Beclin1/14-3-3 complex interacts with GSPT1-238aa and modulates autophagy via the PI3K/AKT/mTOR signaling pathway in GC cells. Our study reveals that GSPT1-238aa, a novel protein encoded by circGSPT1, halts GC tumorigenesis. We also provide insights into the function and underlying molecular mechanisms of GSPT1-238aa in GC and suggest that this protein represents a novel target for GC treatment.


Assuntos
Carcinoma , Neoplasias Gástricas , Autofagia/genética , Carcinogênese/genética , Carcinoma/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Sítios Internos de Entrada Ribossomal , Fatores de Terminação de Peptídeos , Fosfatidilinositol 3-Quinases/genética , RNA Circular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Proteínas Supressoras de Tumor/genética , Vimentina/genética
7.
J Nat Prod ; 85(4): 972-979, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35385664

RESUMO

MS/MS-based molecular networking strain prioritization led to the discovery of a group of cyclic depsipeptides from an endolichenic Xylaria sp. The main component, xylaroamide A (1), was obtained by LC-MS-guided isolation. The planar structure of compound 1 was elucidated via 1D and 2D NMR, as well as MS/MS data. The configurations were fully determined by the combination of advanced Marfey's analysis, partial hydrolysis, Mosher's reaction, and GIAO NMR calculation based on a restricted conformational search. A plausible biosynthetic pathway for xylaroamide A (1) involving a rare trans-acting N-methyltransferase is proposed based on bioinformatics analysis. Xylaroamide A (1) exhibited inhibitory activity against cancer cell lines BT-549 and RKO with IC50 values of 2.5 and 9.5 µM, respectively.


Assuntos
Depsipeptídeos , Xylariales , Depsipeptídeos/química , Conformação Molecular , Estrutura Molecular , Peptídeos Cíclicos/química , Espectrometria de Massas em Tandem , Xylariales/química
8.
Environ Res ; 220: 115170, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36592813

RESUMO

Wood has been a promising water purifier material on account of its abundant natural transport channels, easy processing, and renewability, which is mainly focused on its utilization in growth direction for effective separation.Wood veneer manufacured from raw wood block has a reversed-tree pore structure, and possesses advantages of low cost, easy fabrication, material saving, and abundant sources. To realize its functionalization and practicable application for membrane separation, modification of wood veneer is prerequisite. Herein, thin wood veneer with disparate utilization direction of wood was developed to design filter membrane loading TiO2 nanoparticles for treatment of dye wastewater. Wood veneer with reversed-tree transport pathways exhibits unique porous structure, and filtering direction and wood growth direction is almost orthogonal generated numerous sinuous channels. Thereout, sufficient area for loading TiO2 nanoparticles and contacting pollutants as well as appropriate water transport pathways at significantly shrinking thickness of wood (the thickness of 0.2 mm) can be provide by these sinuous channels. TiO2 nanoparticles was first modified by (3-Aminopropyl)triethoxysilane with high positive charge, and immobilized on negatively charged wood surface through atmospheric impregnation via strong electrostatic attractive interaction. Vast quantities of exposed TiO2 nanoparticles on wood cell lumens significantly enhance the adsorption ability for dye contaminants, resulting in a high membrane separation performance. The flux of TiO2/wood veneer membrane can achieve high level of 636.94 L/(m2h) with considerable methylene blue removal of 99.9% at 0.01 MPa. Meanwhile, it shows good cycling stability as well as decent flexibility and excellent mechanical strength. Moreover, the designed membrane with photocatalytic function of TiO2 also displays impressive decontaminated and recycling ability. The flux can recover its pre-recession level after 10 h light irradiation. The designed TiO2/wood veneer with simple preparation process and excellent water treatment capacity exhibits promising results for practical wastewater treatment.

9.
Front Chem ; 10: 1106869, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36712984

RESUMO

Three new hexadepsipeptides (1-3), along with beauvericin (4), beauvericin D (5), and four 4-hydroxy-2-pyridone derivatives (6-9) were isolated from the endophytic fungus Fusarium sp. CPCC 400857 that derived from the stem of tea plant. Their structures were determined by extensive 1D and 2D NMR, and HRESIMS analyses. The absolute configuration of hexadepsipeptides were elucidated by the advanced Marfey's method and chiral HPLC analysis. Compounds 4, and 7-9 displayed the cytotoxicity against human pancreatic cancer cell line, AsPC-1 with IC50 values ranging from 3.45 to 29.69 µM, and 7 and 8 also showed the antiviral activity against the coronavirus (HCoV-OC43) with IC50 values of 13.33 and 6.65 µM, respectively.

10.
Mol Cancer ; 20(1): 158, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863211

RESUMO

BACKGROUND: Circular RNA (circRNA), a subclass of non-coding RNA, plays a critical role in cancer tumorigenesis and metastasis. It has been suggested that circRNA acts as a microRNA sponge or a scaffold to interact with protein complexes; however, its full range of functions remains elusive. Recently, some circRNAs have been found to have coding potential. METHODS: To investigate the role of circRNAs in gastric cancer (GC), parallel sequencing was performed using five paired GC samples. Differentially expressed circAXIN1 was proposed to encode a novel protein. FLAG-tagged circRNA overexpression plasmid construction, immunoblotting, mass spectrometry, and luciferase reporter analyses were applied to confirm the coding potential of circAXIN1. Gain- and loss-of-function studies were conducted to study the oncogenic role of circAXIN1 and AXIN1-295aa on the proliferation, migration, invasion, and metastasis of GC cells in vitro and in vivo. The competitive interaction between AXIN1-295aa and adenomatous polyposis coli (APC) was investigated by immunoprecipitation analyses. Wnt signaling activity was observed using a Top/Fopflash assay, real-time quantitative RT-PCR, immunoblotting, immunofluorescence staining, and chromatin immunoprecipitation. RESULTS: CircAXIN1 is highly expressed in GC tissues compared with its expression in paired adjacent normal gastric tissues. CircAXIN1 encodes a 295 amino acid (aa) novel protein, which was named AXIN1-295aa. CircAXIN1 overexpression enhances the cell proliferation, migration, and invasion of GC cells, while the knockdown of circAXIN1 inhibits the malignant behaviors of GC cells in vitro and in vivo. Mechanistically, AXIN1-295aa competitively interacts with APC, leading to dysfunction of the "destruction complex" of the Wnt pathway. Released ß-catenin translocates to the nucleus and binds to the TCF consensus site on the promoter, inducing downstream gene expression. CONCLUSION: CircAXIN1 encodes a novel protein, AXIN1-295aa. AXIN1-295aa functions as an oncogenic protein, activating the Wnt signaling pathway to promote GC tumorigenesis and progression, suggesting a potential therapeutic target for GC.


Assuntos
Proteína Axina/genética , Regulação Neoplásica da Expressão Gênica , RNA Circular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Via de Sinalização Wnt , Sequência de Aminoácidos , Animais , Proteína Axina/química , Proteína Axina/metabolismo , Carcinogênese/genética , Linhagem Celular Tumoral , Biologia Computacional , Modelos Animais de Doenças , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Metástase Linfática , Camundongos , Modelos Biológicos , Estadiamento de Neoplasias , Conformação Proteica , Neoplasias Gástricas/patologia
11.
J Biomed Nanotechnol ; 17(9): 1850-1857, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34688330

RESUMO

Chemically modified chitosan nanoparticles (NPs) are capable of releasing their own substances to target cells or tissues, improving microenvironment and promoting wound healing. This study aimed to explore the molecular mechanism underlying chitosan NPs loaded with TGF-ß1 participating in cervical cancer (CC) progression. TGF-ß1-loaded-chitosan NPs were prepared and particle size distribution, zeta potential and encapsulation efficiency of NPs were determined. MTT assay assessed the toxicity of NPs to macrophages. CC cells were co-cultured with TGF-ß1-loaded chitosan NPs (experimental group) or pure chitosan NPs (control group) and cells were cultured alone to produce control group. After treatment, flow cytometry was conducted to detect apoptosis and cycle. Cancer cell migration was evaluated by Transwell assay, and miR-155 and Tim-3 expression was determined. At a ratio of 2:1 chitosan and TGF-ß1, the particle size was102.65±11.98 nm, which was smallest, with high encapsulation rate of 81.26%, and low potential of 1.46±1.71. NP toxicity increased as concentration rose and relative cell proliferation rate was >80%, indicated as non-toxic. CC tissues had positive expression of CD163 and TGF-ß1 (95%) (p < 0.05). Treatment with TGF-ß1-loaded chitosan NPs induced increased apoptosis rate of 9.13±2.15%, reduced migration (67.65±9.91) and invaded cells (19.98±3.41), causing cell accumulation in the S phase when compared to the blank and control groups (p < 0.05). Besides, experimental group exhibited lower expression of miR-155 (0.39±0.59) and higher expression of Tim-3 (2.87± 0.51), which was higher than the blank group and control group. The optimal concentration ratio for producing TGF-ß1-loaded chitosan NPs was 2:1, with less toxicity. The composite NPs suppressed malignant characteristics of CC cells through down-regulation of miR-155 and activation of Tim-3 signal pathway on the surface of macrophages, promoting secretion of macrophage inflammatory factors.


Assuntos
Quitosana , MicroRNAs , Nanopartículas , Neoplasias do Colo do Útero , Regulação para Baixo , Feminino , Receptor Celular 2 do Vírus da Hepatite A , Humanos , MicroRNAs/genética , Fator de Crescimento Transformador beta1/genética , Microambiente Tumoral , Neoplasias do Colo do Útero/tratamento farmacológico
12.
Sensors (Basel) ; 21(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34450704

RESUMO

Surface plasmonic sensors have been widely used in biology, chemistry, and environment monitoring. These sensors exhibit extraordinary sensitivity based on surface plasmon resonance (SPR) or localized surface plasmon resonance (LSPR) effects, and they have found commercial applications. In this review, we present recent progress in the field of surface plasmonic sensors, mainly in the configurations of planar metastructures and optical-fiber waveguides. In the metastructure platform, the optical sensors based on LSPR, hyperbolic dispersion, Fano resonance, and two-dimensional (2D) materials integration are introduced. The optical-fiber sensors integrated with LSPR/SPR structures and 2D materials are summarized. We also introduce the recent advances in quantum plasmonic sensing beyond the classical shot noise limit. The challenges and opportunities in this field are discussed.


Assuntos
Fibras Ópticas , Ressonância de Plasmônio de Superfície , Monitoramento Ambiental
13.
J Asian Nat Prod Res ; 23(5): 504-511, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32762359

RESUMO

In this work, we isolated and characterized fusapyrone A (1), a new γ-pyrone derivative, along with six previously described compounds from the rice fermentation of Fusarium sp. CPCC 401218, a fungus collected from the desert. The structure of 1 was characterized using various spectroscopic analyses, such as MS, IR, 1D, and 2D NMR. The absolute configuration of 1 was determined through the use of 13C NMR chemical shifts, electronic circular dichroism (ECD) and optical rotation (OR) calculations. Compound 1 was found to have weak antiproliferative activity for Hela cells, with an IC50 of 50.6 µM.[Formula: see text].


Assuntos
Fusarium , Pironas , Células HeLa , Humanos , Estrutura Molecular , Pironas/farmacologia
14.
Protoplasma ; 258(2): 361-370, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33106960

RESUMO

As the by-products of edible oil production with rich lignin, the reserves of Camellia oleifera shell were abundant and had a great economic value. Lignin was the most important limiting factor during the conversion of plant biomass to pulp or biofuels, which mainly deposited in the stone cells of C. oleifera shells. Thus, its lignin deposition made the function of stone cells in the ripening process of the shell clearer, and provided a theoretical basis for the potential utilization of the biomass of C. oleifera shells. In this study, the paraffin embedding method was used to investigate the development and difference of stone cell in the fruitlet. The lignin deposition characteristics of stone cell were analyzed by the fluorescence microscopy and Wiesner and Mäule method. The chemical-functional group types of lignin in the stone cell of C. oleifera shell were examined by the ultraviolet spectrophotometer and transform infrared spectroscopy. The stone cells, vessels, parenchyma, and vascular tissue had existed during the young fruit growing period. The anatomical characteristics and the cell tissue ratio inverse relationship between stone cell and parenchymal cell suggested that stone cells developed from parenchymal cells. With the growth of shell, the stone cell wall thickened, and thickness-to-cavity ratio from 0 to 3.6. The fluorescent results showed that lignin content increased continuously; during shell development, the mean brightness of stone cell wall from 0 to 77.9 sections was stained with phloroglucinol-HCl, and Mäule revealed the presence of G-S-lignin in stone cells, and ImageJ results showed that G-lignin was distributed in the entire stone cell wall, while S-lignin deposition accounted for 48.59% of the cell wall area. In the FTIR spectra, the shell was identified as containing G-S-lignin.


Assuntos
Camellia/química , Lignina/metabolismo , Plantas/química
15.
Front Chem ; 8: 241, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32300584

RESUMO

Hard carbon derived from fossil products is widely used as anode material for lithium-ion batteries. However, there are still several main shortcomings such as high cost, and poor rate performance, which restrict its wide application. Then tremendous efforts have been devoted to developing biomaterials in the battery applications. Recently, especially agricultural and industrial by-products have attracted much attention due to the electric double-layer capacitors. Herein, we report the sulfur-doped hard carbon (SHC) materials from the tannin-furanic resins (TF-Resin) of the derived agricultural by-products, followed by enveloping rGO on its surface through the hexadecyl trimethyl ammonium bromide. SHC provides sites for the storage of lithium, while the rGO layers can offer a highly conductive matrix to achieve good contact between particles and promote the diffusion and transport of ions and electrons. As a result, the SHC@rGO shows excellent lithium storage performance with initial discharge capacity around 746 mAh g-1 at a current density of 50 mA g-1, and shows superb stability keeping capacity retention of 91.9% after 200 cycles. Moreover, even at a high current density of 2,000 mAg-1, SHC@rGO still delivers a specific capacity of 188 mAg-1. These desired promising properties are active to the implement in the possible practical application.

16.
Sci Rep ; 9(1): 16496, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712585

RESUMO

Bamboo with the outstanding properties, such as good mechanical strength, fast growth rate and low growth cost, is considered as one of utilitarian structural nature materials. But bamboo is easy to get mildewed resulting in disfiguration and fungi corrosion. In this work, a facile method was developed to improve the mildew-proofing capability of bamboo. Mussel-inspired polydopamine (PDA) with biomimetic adhesion function and highly active functional groups was employed to immobilize highly-dispersed Ag and TiO2 nanoparticles on the surface of bamboo via an in-situ growth method. Integrating the uniform PDA coating, photocatalytic function of TiO2 nanoparticles and bactericidal role of Ag nanoparticles, the mildew-proofing capability of bamboo is enhanced significantly. The results show a non-covalent interaction is more likely to account for the binding mechanism of PDA to bamboo. And the prepared bamboo samples show good photocatalytic performance and have excellent resistance leachability. Meanwhile, the mildew-proofing property of prepared bamboo sample was greatly improved.


Assuntos
Indóis , Nanopartículas Metálicas , Polímeros , Sasa , Prata , Titânio , Biomimética , Catálise , Resistência à Doença , Fungos , Indóis/química , Indóis/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Processos Fotoquímicos , Doenças das Plantas , Polímeros/química , Polímeros/metabolismo , Sasa/metabolismo , Sasa/microbiologia , Sasa/ultraestrutura , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/química
17.
Protoplasma ; 256(4): 1145-1151, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30953174

RESUMO

Generally, Camellia oleifera shells are byproducts of edible oil production and are often incinerated or discarded as agricultural waste without any sustainable uses. Although numerous studies have focused on the C. oleifera shell, few studies have examined its biological characteristics, particularly its internal mesoporosity. The aim of the present study was to elucidate the microscopic biological structure of C. oleifera shells to explore their potential applications. Paraffin-embedded slices of C. oleifera shells were observed on different planes using an optical microscope. Supercritically dried samples were prepared and assessed using the nitrogen adsorption-desorption technique to reveal mesopore structural features. The present article shows that C. oleifera shells were mainly made up of stone cells, parenchyma tissue, spiral vessels, and vascular bundles. The key features of the cells were the pits in the cell walls of stone cells and vessels, which are associated with the abundant mesopores in C. oleifera shells. C. oleifera shells have an advantage over woody materials based on their mesoporosity features. C. oleifera shells are ideal raw materials that could serve as biomass templates or find applications as other high-performance biomimetic materials.


Assuntos
Camellia/ultraestrutura , Sementes/ultraestrutura , Adsorção , Camellia/química , Indústria de Processamento de Alimentos , Porosidade , Sementes/química , Resíduos
18.
Org Lett ; 21(5): 1530-1533, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30785290

RESUMO

Isocoumarindole A (1), a novel polyketide synthetase-nonribosomal peptide synthetase (PKS-NRPS) hybrid metabolite, was isolated from the endolichenic fungus Aspergillus sp. CPCC 400810. The structure of isocoumarindole A (1) was featured by an unprecedented skeleton containing chlorinated isocoumarin and indole diketopiperazine alkaloid moieties linked by a carbon-carbon bond, which was determined by a combination of spectroscopic analyses, Marfey's method, and calculations of NMR chemical shifts, ECD spectra, and optical rotation values. Isocoumarindole A showed significant cytotoxicity and mild antifungal activities.


Assuntos
Aspergillus/química , Dicetopiperazinas/química , Alcaloides Indólicos/química , Alcaloides Indólicos/metabolismo , Isocumarinas/química , Isocumarinas/metabolismo , Peptídeo Sintases/metabolismo , Fungos , Halogenação , Alcaloides Indólicos/isolamento & purificação , Isocumarinas/isolamento & purificação , Estrutura Molecular , Peptídeo Sintases/química
19.
RSC Adv ; 9(28): 16035-16039, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35521380

RESUMO

The following compounds were isolated from acetate extracts of Chaetomium globosum 7951 solid cultures: demethylchaetocochin C (1) and chaetoperazine A (3), two new epipolythiodioxopiperazine (ETP) alkaloids, a novel pyridine benzamide, 4-formyl-N-(3'-hydroxypyridin-2'-yl) benzamide (6), and three known ETP derivatives (2, 4, and 5). The structures of these compounds were determined using extensive spectroscopic data analysis. Compounds 1-3, and 6, inhibited the growth of MCF-7, MDA-MB-231, H460 and HCT-8 cells with an IC50 of 4.5 to 65.0 µM.

20.
Protoplasma ; 255(6): 1777-1784, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29868989

RESUMO

The main product of Camellia oleifera is edible oil made from the seeds, but huge quantities of agro-waste are produced in the form of shells. The primary components of C. oleifera fruit shell are cellulose, hemicellulose, and lignin, which probably make it a good eco-friendly non-wood material. Understanding the structure of the shell is however a prerequisite to making full use of it. The anatomical structure of C. oleifera fruit shells was investigated from macroscopic to ultrastructural scale by stereoscopic, optical, and scanning electron microscopy. The main cell morphology in the different parts of the shell was observed and measured using the tissue segregation method. The density of the cross section of the shell was also obtained using an X-ray CT scanner to check the change in texture. The C. oleifera fruit pericarp was made up of exocarp, mesocarp, and endocarp. The main types of exocarp cells were stone cells, spiral vessels, and parenchyma cells. The mesocarp accounted for most of the shell and consisted of parenchyma, tracheids, and some stone cells. The endocarp was basically made up of cells with a thickened cell wall that were modified tracheid or parenchyma cells with secondary wall thickening. The most important ultrastructure in these cells was the pits in the cell wall of stone and vessel cells that give the shell a conducting, mechanical, and protective role. The density of the shell gradually decreased from exocarp to endocarp. Tracheid cells are one of the main cell types in the shell, but their low slenderness (length to width) ratio makes them unsuitable for the manufacture of paper. Further research should be conducted on composite shell-plastic panels (or other reinforced materials) to make better use of this agro-waste.


Assuntos
Camellia/anatomia & histologia , Frutas/anatomia & histologia , Camellia/ultraestrutura , Frutas/ultraestrutura , Tomografia Computadorizada por Raios X , Madeira/ultraestrutura
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