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1.
Inorg Chem ; 60(6): 3539-3542, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33650857

RESUMEN

Explorations of new types of borates are important because of their promising application in diverse fields. A new bismuth-containing boroselenite, Bi2[B2(SeO3)6], has been obtained through high-temperature solid-state reaction in a closed system. Bi2[B2(SeO3)6] possesses a zero-dimensional [B2(SeO3)6]6- anionic group that does not belong to any types of reported boroselenites. Besides, Bi2[B2(SeO3)6] is the first boroselenite with lone-pair electrons containing a metal ion as the countercation. More interestingly, on the basis of the first-principles calculations, this compound displays a large birefringence (0.090) at 1064 nm.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38922439

RESUMEN

In this study, a convenient chitosan oligosaccharide laser lithograph (COSLL) technology was developed to fabricate laser-induced graphene (LIG) electrodes and flexible on-chip microsupercapacitors (MSCs). With a simple one-step CO2 laser, the pyrolysis of a chitosan oligosaccharide (COS) and in situ welding of the generated LIGs to engineering plastic substrates are achieved simultaneously. The resulting LIG products display a hierarchical porous architecture, excellent electrical conductivity (6.3 Ω sq-1), and superhydrophilic properties, making them ideal electrode materials for MSCs. The pyrolysis-welding coupled mechanism is deeply discussed through cross-sectional analyses and finite element simulations. The MSCs prepared by COSLL exhibit considerable areal capacitance of over 4 mF cm-2, which is comparable to that of the polyimide-LIG-based counterpart. COSLL is also compatible with complementary metal-oxide-semiconductor (CMOS) and micro-electro-mechanical system (MEMS) processes, enabling the fabrication of LIG/Au MSCs with comparable areal capacitance and lower internal resistance. Furthermore, the as-prepared MSCs demonstrate excellent mechanical robustness, long-cycle capability, and ease of series-parallel integration, benefiting their practical application in various scenarios. With the use of eco-friendly biomass carbon source and convenient process flowchart, the COSLL emerges as an attractive method for the fabrication of flexible LIG on-chip MSCs and various other advanced LIG devices.

3.
Front Plant Sci ; 13: 851077, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35401649

RESUMEN

Treatments with abiotic elicitors can efficiently induce the accumulation of specialized metabolites in plants. We used a combined omics approach to analyze the elicitation effects of MeJa, AgNO3, and PEG on camptothecin (CPT) biosynthesis in Camptotheca acuminata plantlets. Untargeted analyses revealed that treatments with MeJa, AgNO3, and PEG significantly inhibited the photosynthetic pathway and promoted carbon metabolism and secondary metabolic pathways. The CPT levels increased by 78.6, 73.3, and 50.0% in the MeJa, AgNO3, and PEG treatment groups, respectively. Using C. acuminata plantlets after elicitation treatment, we mined and characterized 15 new alkaloids, 25 known CPT analogs and precursors, 9 iridoid biosynthetic precursors, and 15 tryptamine biosynthetic precursors based on their MS/MS fragmentation spectra. Using 32 characterized genes involved in CPT biosynthesis as bait, we mined 12 prioritized CYP450 genes from the 416 CYP450 candidates that had been identified based on co-expression analysis, conserved domain analysis, and their elicitation-associated upregulation patterns. This study provides a comprehensive perspective on CPT biosynthesis in C. acuminata plantlets after abiotic elicitation. The findings enable us to elucidate the previously unexplored CYP450-mediated oxidation steps for CPT biosynthesis.

4.
Chem Commun (Camb) ; 57(87): 11525-11528, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34661229

RESUMEN

A new noncentrosymmetric iron-iodate-fluoride Ba2[FeF4(IO3)2]IO3 was ingeniously obtained based on the centrosymmetric Ba[FeF4(IO3)] through chemical tailoring. Ba2[FeF4(IO3)2]IO3 exhibits a strong phase-matchable second-harmonic generation effect, a large band gap, and a wide mid-infrared transparent window. The chemical tailoring design based on oxide-fluoride anions affords a feasible approach to design nonlinear optical materials.

5.
Chem Sci ; 12(27): 9333-9338, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34349903

RESUMEN

A novel salt-inclusion fluoroiodate [GaF(H2O)][IO3F] derived from CsIO2F2 was ingeniously obtained through anisotropic polycation substitution. Because the catenulate [GaF(H2O)]2+ framework serves as a template for the favorable assembly of the polar [IO3F]2- groups and contributes to the nonlinear coefficient, [GaF(H2O)][IO3F] exhibits a greatly improved second-harmonic generation (SHG) effect of 10 times that of KH2PO4 (KDP) and a considerable band gap of 4.34 eV compared to the parent compound CsIO2F2 (3 × KDP, 4.5 eV). Particularly, to the best of our knowledge, [GaF(H2O)][IO3F] has the largest laser-induced damage threshold (LDT) of 140 × AgGgS2 of the reported iodates. All these results signify that [GaF(H2O)][IO3F] is a promising nonlinear optical (NLO) crystal. This work also proposes that anisotropic polycation substitution is an effective approach to optimize the SHG effect and develop excellent NLO materials.

6.
J Chromatogr A ; 1620: 461036, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32201039

RESUMEN

Leaves, flowers, fruits and stems (44 sample groups) were collected from mature Camptotheca acuminate during 2017.3-2018.3 and classified by ultra-high performance liquid chromatography coupled with quadrupole-time of flight-mass spectrometry based metabolomics. One hundred metabolites including forty-seven alkaloids, fifteen terpenes, thirty-two polyphenols and six other metabolites were rapidly identified through the in-house database alignment at first glance. Thirty-three alkaloids classified into five groups including camptothecin group (CG1-13), pumiloside group (PG1-5), strictosidinic acid group (SG1-3), vincosamide group (VG1-7), and a new hybrid group, vincosamide-camptothecin group (VC1-5) were mined and further characterized by MS/MS analyses. The identification of two untapped biosynthetic precursors, 2-hydroxypumiloside (PG2) and 16­hydroxy­15, 16-dihydrocamptothecoside (CG3), along with sixteen new alkaloids enables us for a better understanding of camptothecin biogenetic reasoning. The underlying enzymes involved in camptothecin biosynthesis were also proposed according to the guiding metabolic map, thus purposefully mining of enzymes involved in the downstream biosynthetic pathway of camptothecin could be initiated with the help of this map.


Asunto(s)
Alcaloides/análisis , Vías Biosintéticas , Camptotheca/química , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Camptotecina/análogos & derivados , Camptotecina/análisis , Camptotecina/química , Camptotecina/metabolismo , Carbolinas/análisis , Carbolinas/química , Bases de Datos como Asunto , Análisis Discriminante , Glicósidos/análisis , Glicósidos/química , Alcaloides Indólicos/análisis , Alcaloides Indólicos/química , Análisis de los Mínimos Cuadrados , Redes y Vías Metabólicas , Metaboloma , Metabolómica , Análisis Multivariante , Análisis de Componente Principal
7.
Fitoterapia ; 134: 113-128, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30794920

RESUMEN

The plant derived camptothecin (CPT) is a pentacyclic pyrroloquinoline alkaloid with unique antitumor activity. Successive discoveries of new CPT-producing plants occurred in recent years due to market demands. The scattered distribution among angiosperms drew researchers' attention. The aim of this review is to appraise the literature available to date for CPT distribution and the phytochemistry of these CPT-producing plants. Metabolite comparative analyses between the plants were also conducted for tracking of possible clues for CPT biosynthesis. Forty-three plant species in total were reported to possess CPT-producing capability, and one hundred twenty-five alkaloids classified into three major categories are summarized herein. Metabolite comparative analysis between these plants suggests the probability that the formation of the central intermediate for CPT biosynthesis has multiple origins. A more complete biogenetic reasoning for CPT and its structural homolog was delineated based on this fragmentary phytochemical evidence from a chemical point of view. Furthermore, an in-house compound database was constructed for further metabolomic analysis.


Asunto(s)
Antineoplásicos Fitogénicos/biosíntesis , Camptotecina/biosíntesis , Magnoliopsida/química , Magnoliopsida/clasificación , Estructura Molecular , Fitoquímicos/biosíntesis
8.
Yi Chuan ; 29(7): 859-66, 2007 Jul.
Artículo en Zh | MEDLINE | ID: mdl-17646153

RESUMEN

The full-length coding region (open reading frame, ORF) of low-molecular-weight glutenin subunit (LMW-GS ) gene was amplified from Sichuan wheat landrace accession AS1643 by using the primer pairs P1/P2, which were designed according to wheat LMW-GS conservative domains. The amplified DNA fragment was separated and recovered from agarose gel, subsequently cloned into pMD18-T vector, and then transformed into E. coli strain DH5a. One positive clone LMW-AS1643 (GenBank accession No. EF 190322) was selected and sequenced. It had a coding region of 909 bp, and encoded a mature protein of 302 amino acid residues. Sequence analysis suggested that LMW-AS1643 was a typical LMW-GS gene. The deduced amino acid sequence comparison suggested that LMW-AS1643 had a high similarity with other known LMW-GS genes, with the highest similarity of 93.40 %Bioinformatics analysis indicated that among the three types of secondary structures, content of coil was the highest with 67.90 %, a-helix was the second with 30.46%, and b-sheet was the lowest with 1.64%.


Asunto(s)
Glútenes/genética , Proteínas de Plantas/genética , Triticum/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Glútenes/química , Datos de Secuencia Molecular , Peso Molecular , Proteínas de Plantas/química , Reacción en Cadena de la Polimerasa , Estructura Secundaria de Proteína , Alineación de Secuencia
9.
Ying Yong Sheng Tai Xue Bao ; 23(8): 2212-8, 2012 Aug.
Artículo en Zh | MEDLINE | ID: mdl-23189701

RESUMEN

Taking Trametes gallica mycelium pellets, Bacillus cereus, and their co-immobilized biomaterial as bio-adsorbents, this paper studied their Pb2+ adsorption under effects of different contact time, medium initial pH value and Pb2+ concentration, and bio-adsorbent concentration, and compared the infrared spectra of the bio-adsorbents before and after Pb2+ absorption. The Pb2+ adsorption efficiency of the bio-adsorbents was the highest when the bio-adsorbent concentration was 2 g x L(-1), initial pH was 5.0, initial Pb2+ concentration was 50 mg x L(-1), and contact time was 1 h, with the Pb2+ biosorption rate being 71.7% for the mycelium pellets of T. gallica, 91.0% for B. cereus, and 96.9% for the co-immobilized biomaterial. The infrared spectra of the bio-adsorbents were mainly consisted of the absorption zones of protein, carbohydrates, and sulphur- and phosphors-based groups, suggesting that hydroxyl, carboxyl, and sulphur- and phosphate-based groups played important roles in the Pb2+ adsorption by the bio-adsorbents.


Asunto(s)
Bacillus cereus/metabolismo , Plomo/aislamiento & purificación , Trametes/metabolismo , Eliminación de Residuos Líquidos/métodos , Adsorción , Biodegradación Ambiental , Células Inmovilizadas/metabolismo , Plomo/metabolismo , Espectrofotometría Infrarroja , Aguas Residuales/química
10.
Biosens Bioelectron ; 26(8): 3614-9, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21382705

RESUMEN

In this paper, we demonstrated that bovine serum albumin (BSA) stabilized Au clusters exhibited highly intrinsic peroxidase-like activity. Unlike nature enzymes, the BSA-Au clusters have strong robustness and can be used over a wide range of pH and temperature. Because of ultra-small size, good stability and high biocompatibility in water solution compare with other kinds of nanoparticles as peroxidase mimetics, such as Fe(3)O(4), FeS or graphene oxide, it is more competent for bioanalysis. Furthermore, we make use of the novel properties of BSA-Au clusters as peroxidase mimetics to detect H(2)O(2). The as-prepared BSA-Au clusters were used to catalyze the oxidation of a peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) by H(2)O(2) to the oxidized colored product, and which provides a colorimetric detection of H(2)O(2). As low as 2.0 × 10(-8)M H(2)O(2) could be detected with a linear range from 5.0 × 10(-7) to 2.0 × 10(-5)M via this method. More importantly, a sensitive and selective method for xanthine detection was developed using xanthine oxidase (XOD) and the as-prepared BSA-Au clusters. The detection limit of this assay for xanthine was 5 × 10(-7)M and the proposed method was successfully applied for the determination of xanthine in urine and human serum sample.


Asunto(s)
Materiales Biomiméticos/química , Oro/química , Peroxidasa/química , Albúmina Sérica Bovina/química , Xantina/análisis , Animales , Catálisis , Bovinos , Humanos , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Temperatura , Xantina/sangre , Xantina/orina
11.
Ying Yong Sheng Tai Xue Bao ; 22(12): 3293-9, 2011 Dec.
Artículo en Zh | MEDLINE | ID: mdl-22384600

RESUMEN

With a shaker, this paper studied the characteristics of the biosorption of crystal violet and malachite green by Rhodotorula graminis Y-5 under different adsorption time, initial pH, and temperature, as well as the desorption and recycling use of the dyes. The biosorption of crystal violet and malachite green by R. graminis Y-5 had the peaks (93.8% and 87.7%, respectively) at pH 7.0, dye concentration 50 mg x L(-1), 150 r x min(-1), 30 degrees C, and lasting 10 hours. After desorption, the biosorption rate of crystal violet and malachite green by R. graminis was 85.5% and 78.5%, respectively, indicating that the biosorption of crystal violet and malachite green was reversible, and the recycling use of the dyes by R. graminis was quite good, i. e., the dyes were renewable and could be recycled. Biosorption could be the mechanism of the decolorization of the dyes. The dyes were mostly adsorbed on the R. graminis surface -OH. The adsorption process was fast, efficient, and reversible, suggesting that R. graminis had a high potential for waste water treatment.


Asunto(s)
Violeta de Genciana/aislamiento & purificación , Rhodotorula/metabolismo , Colorantes de Rosanilina/aislamiento & purificación , Contaminantes del Agua/aislamiento & purificación , Adsorción , Antiinfecciosos Locales/aislamiento & purificación , Antiinfecciosos Locales/metabolismo , Colorantes/aislamiento & purificación , Colorantes/metabolismo , Violeta de Genciana/metabolismo , Rhodotorula/fisiología , Colorantes de Rosanilina/metabolismo , Contaminantes del Agua/metabolismo
12.
Ying Yong Sheng Tai Xue Bao ; 22(12): 3300-6, 2011 Dec.
Artículo en Zh | MEDLINE | ID: mdl-22384601

RESUMEN

The characteristics of the induction of laccase in Trametes gallica under different initial cultural pH, incubation time by different inducers were discussed, as well as the effects of temperature, pH and time on laccase degradation of six dyes and four organophosphors. The results showed that RB-bright blue, ABTS and o-toluidine affected the production of laccase at different levels, and ABTS was the best inductive agent in our test conditions, whose optimal initial pH and incubation time were 4.0 and 13 days, respectively. The appropriate reaction temperature of the laccase produced was 38 degrees C, and it got a good stability, for it could retain 78.6% of the enzyme activity after 20 min holding at 40 degrees C. Mediated by ABTS, the optimal temperature for laccase to degrade the six types of neutral dyes could be divided into two cases, that was 30 degrees C (neutral black, neutral bordeaux, neutral pink, methyl orange) and 60 degrees C (neutral dark yellow, cresol red), the optimal pH were 6.0 (neutral black), 2.0 (neutral bordeaux, neutral pink) and 4.0 (methyl orange, neutral dark yellow, cresol red), respectively, while the optimal times separately were 6 h (methyl orange, neutral dark yellow, cresol red), 12 h (neutral pink) and 24 h (neutral bordeaux). And using the same inductive agent, the best temperature for laccase to degrade dimethoate, chlorpyrifos, trichlorfon and parathion-pyridazine was 25 degrees C, the suitable time was 9 h, and the optimal pH was 10.0 for dimethoate, chlorpyrifos and parathion-pyridazine, and 8.0 for trichlorfon.


Asunto(s)
Benzotiazoles/farmacología , Colorantes/aislamiento & purificación , Lacasa/biosíntesis , Compuestos Organofosforados/aislamiento & purificación , Ácidos Sulfónicos/farmacología , Trametes/enzimología , Biodegradación Ambiental , Colorantes/metabolismo , Inducción Enzimática/efectos de los fármacos , Compuestos Organofosforados/metabolismo , Plaguicidas/aislamiento & purificación , Plaguicidas/metabolismo
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