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1.
Chempluschem ; 85(7): 1523-1528, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32662951

RESUMO

A heating treatment method for the synthesis of fluorescent nanoparticles using simple N-(9-fluorenylmethoxycarbonyl) (Fmoc)-protected tripeptides is reported. Two pairs of Fmoc-protected tripeptides (Fmoc-FR1 R2 , R1 =F or W, R2 =H or Y) were designed by changing the amino acid sequences of the peptides. The peptides can self-assemble into nanofibers at lower temperatures, which will spontaneously transform into fluorescent nanoparticles under heating treatment. Moreover, the fluorescence properties of the self-assembled structures can be affected by changing amino acids in the middle of the tripeptide. Specifically, tryptophan (W) can promote fluorescence of the assemblies incubated at high temperatures. Thus, the temperatures and amino sequences of the Fmoc-protected tripeptides have significant effects on the fluorescence of the assembled nanostructures. The results provide a design principle for self-assembled fluorescent peptide nanostructures with potential biomedical applications.

2.
Phytomedicine ; 77: 153273, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32663710

RESUMO

BACKGROUND: The selection of quality control indicators in a complex system is a key scientific issue for the study of Chinese materia medica (CMM), which is directly related to its safety and efficacy. In order to scientifically understand and control the quality of CMM, quality marker (Q-marker) has been recently raised as a new concept, which provided a novel research idea for the quality control and evaluation of CMM. PURPOSE: By a new and integrated "spider-web" mode, Q-markers of Xuefu Zhuyu capsule (XZC) were comprehensively uncovered, conducing to great improvement of quality control of XZC. METHODS: Mainly established by three dimensions derived from six variables including content, stability and activity, "spider-web" mode was constructed to evaluate Q-marker property of candidate compounds by taking regression area of the tested compounds into account. RESULTS: The candidate compounds with larger regression area were preferentially adopted as Q-markers, which should possess the satisfactorily integrated properties of content, stability and activity. Six compounds, naringin, isoliquiritin, paeoniflorin, protocatechuic acid, neohesperidin and ferulic acid, were identified and preferred as Q-markers of XZC. CONCLUSION: Based on "spider-web" mode, Q-markers from Xuefu Zhuyu capsule were successfully screened, which would substantially perform quality control of XZC and prove the feasibility of "spider-web" mode in solving the selection of quality control indicators from compound formulae.

3.
J Colloid Interface Sci ; 578: 218-228, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32531552

RESUMO

In this work, we report a strategy to self-assemble multifunctional hydrogels composed of highly ordered polyoxometalates (POMs) helical arrays using a liquid crystalline tripeptide as the template. The cationic peptide can self-assemble into long-range ordered nanofilaments with a diameter of ~4.1 nm in aqueous media. Through the incorporation of various multivalent polyoxometalates (POMs), the POMs clusters can spontaneously organize into periodic nanowire arrays by the colloidal co-assembly with the as-prepared nematic peptide nanofilaments. This leads to the formation of hybrid gels with tunable mechanical strength by simply changing the charge number of the POMs. The H3PW12O40 (noted as PW) clusters@peptide hybrid hydrogels show excellent adsorption performance of dyes. Moreover, the long-range aligned PW clusters within the co-assembled fiber bundles exhibit great improvement in the efficiency of photodegradation of dyes, which shows 8.7 times higher than that of the pristine PW clusters in the homogeneous phase. The synergistic effect between the adsorption and catalytic process within the hybrid gels is considered to be responsible for its highly catalytic activity. This work highlights a general pathway upon the well-defined organization of the various components into hybrid materials with superior properties using simple peptide liquid crystals as templates.

4.
ACS Appl Mater Interfaces ; 12(28): 31830-31841, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539326

RESUMO

The growing enthusiasm to mimic the luminous properties of fluorescent proteins (FPs) has expanded to include the potential biomedical applications of FP analogues. We developed a series of non-fluorescent oligopeptides (Fc-(X)n; where X = F, Y, W, and H; n = 1-3) that can aggregate into fluorescent nanoparticles with rainbow colors, termed the peptidyl rainbow kit (PRK). The PRK encompasses the full visible color spectrum, and its photoluminescent properties may have originated from aggregation-induced emission (AIE). Intermolecular forces restricted the intramolecular motions of the oligopeptide residues, providing a barrier to non-radiative conformational relaxation pathways and leading to AIE fluorescence. The PRK oligopeptides are pH sensitive, biocompatible, and photostable under physiological conditions, making the PRK a promising fluorescence candidate for biomedical applications.

5.
Biochim Biophys Acta Mol Basis Dis ; 1866(10): 165856, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32512188

RESUMO

Epigallocatechin gallate (EGCG), as one of the main ingredients of green tea, has been reported to have potential prevention on a variety of solid tumors. However, the system-wide molecular mechanisms targeted to EGCG's anti-tumor effect have not been illustrated. Here, AGS and SGC7901 GC cells were used to investigate the EGCG-mediated change of gene expression. Our data showed that EGCG retarded cell growth and promoted cell death of GC in dose-dependent manner. Analyses based on transcription, translation as well as function were performed to explore the elusive anticancer role of EGCG. Of them, cell cycle was probably implicated key pathway of EGCG. Besides, our data revealed numerous LncRNAs activated after EGCG treatment. In this study, LINC00511 was discovered to be suppressed by EGCG and highly expressed in GC cells and tissues. Knockdown of LINC00511 inhibited cell growth and promoted cell death ratio in GC. Additionally, our data suggested LINC00511 could decrease the expression of miR-29b, followed by inducing GC development. Knockdown of miR-29b recovered the effects of LINC00511 silencing. In addition, we found overexpression of KDM2A, a target of miR-29b, would rescue the level of LINC00511. All the data showed that the LINC00511/miR-29b/KDM2A axis can be used as a diagnostic and therapeutic target for GC.

6.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1509-1514, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32489027

RESUMO

Viral pneumonia is caused by a spreading of lung infection caused by respiratory viruses. Some virus infections were found to be highly aggressive, leading to lung inflammation and severe damage in respiratory system with high fatality rate. Currently, there is no effective therapeutic drugs in the clinic. The common clinical symptoms of viral pneumonias include fever, rhinitis, runny nose, nonproductive cough, fatigue, myalgias and headaches after the immune system being tricked by driving cytokines and overactivated immune response induced by cytokine storms. Patients with severe symptoms could get persistent high fever, dysfunctional breathing, consciousness disorders and even respiratory failure, post-inflammatory pulmonary fibrosis, multi-organ damages, shock and so on. Most clinical treatments are used to inhibit virus replication, relieve symptoms, inhibit excessive inflammatory response, regulate immune balance and protect organs. Both applied and basic research demonstrate that Chinese patent medicine has certain anti-viral effects, effectively inhibiting viral pneumonia transiting from mild to severe, rapid relieving of patient symptoms because of their multi-component and multi-target integrated roles. This review has summarized the reports on the treatment of viral pneumonia. Based on the pathogenic characteristics of viral pneumonia, this paper summarizes the diverse roles of the marketed Chinese patent medicine, such as their effects in inhibiting the progress of viral replication and overactivated inflammatory response, regulating immune balance, attenuating pulmonary fibrosis and so forth. Our paper summarizes the advantages of Chinese patient medicine in the treatment of viral pneumonia, based on which improvements of clinical therapy are expected to be made soon.


Assuntos
Pneumonia Viral , Tosse , Febre , Humanos , Medicamentos sem Prescrição
7.
J Colloid Interface Sci ; 577: 388-396, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497920

RESUMO

We report the self-assembly of an ultra-pH-sensitive hydrogel from a simple dipeptide derivative, ferrocene-diphenylalanine (noted as Fc-FF). The pure Fc-L-Phe-L-Phe-OH (noted as (L)-Fc-FF) or Fc-D-Phe-D-Phe-OH (noted as (D)-Fc-FF) peptide could self-assemble into right- or left-handed nanohelices in a mixture of water and organic solvent leading to formation of stable chiral hydrogels at a very narrow pH range of 5.7-5.9. Intriguingly, if we used a racemic mixture (noted as (L,D)-Fc-FF) of (L)-Fc-FF and (D)-Fc-FF, stable hydrogels could only be formed at much lower pH values with a weak mechanical property. The results indicated that the molecular chirality has great influence on the gelation of the peptides. Moreover, we investigated the gelation behaviour of the peptides in various solvents. Here the water molecules are essential in directing the chiral self-assembly of Fc-FF into entangled chiral nanostructures, leading to the formation of stimuli-responsive hydrogels. And in the presence of water molecules, a small amount of organic co-solvents also has significant effect on the gelation of Fc-FF peptides. This work demonstrated that the gelation of such a bioorganometallic molecule is very sensitive to the molecular conformation of itself and the self-assembly environment (pH, solvents, etc.), which has potential applications in chemical sensing and biomedicine.

8.
Small ; 16(23): e1906701, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32378351

RESUMO

A magnetic urchin-like microswimmer based on sunflower pollen grain (SPG) that can pierce the cancer cell membrane and actively deliver therapeutic drugs is reported. These drug loaded microperforators are fabricated on a large scale by sequentially treating the natural SPGs with acidolysis, sputtering, and vacuum loading. The microswimmers exhibit precise autonomous navigation and obstacle avoidance in complex environments via association with artificial intelligence. Assemblies of microswimmers can further enhance individual motion performance and adaptability to complicated environments. Additionally, the experimental results demonstrate that microswimmers with nanospikes can accomplish single-cell perforation for direct delivery under an external rotating magnetic field. Drugs encapsulated in the inner cavity of the microperforators can be accurately delivered to a specific site via remote control. These dual-action microswimmers demonstrate good biocompatibility, high intelligence, precision in single-cell targeting, and sufficient drug loading, presenting a promising avenue for many varieties of biomedical applications.

9.
Nutrients ; 12(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290071

RESUMO

Several studies in the past decades have reported anti-tumor activity of the bioactive compounds extracted from tea leaves, with a focus on the compound epigallocatechin-3-gallate (EGCG). However, further investigations are required to unravel the underlying mechanisms behind the anti-tumor activity of EGCG. In this study, we demonstrate that EGCG significantly inhibits the growth of 4T1 breast cancer cells in vitro and in vivo. EGCG ameliorated immunosuppression by significantly decreasing the accumulation of myeloid-derived suppressor cells (MDSCs) and increasing the proportions of CD4+ and CD8+ T cells in spleen and tumor sites in 4T1 breast tumor-bearing mice. Surprisingly, a low dose of EGCG (0.5-5 µg/mL) effectively reduced the cell viability and increased the apoptosis rate of MDSCs in vitro. EGCG down-regulated the canonical pathways in MDSCs, mainly through the Arg-1/iNOS/Nox2/NF-κB/STAT3 signaling pathway. Moreover, transcriptomic analysis suggested that EGCG also affected the non-canonical pathways in MDSCs, such as ECM-receptor interaction and focal adhesion. qRT-PCR further validated that EGCG restored nine key genes in MDSCs, including Cxcl3, Vcan, Col4a1, Col8a1, Oasl2, Mmp12, Met, Itsnl and Acot1. Our results provide new insight into the mechanism of EGCG-associated key pathways/genes in MDSCs in the murine breast tumor model.

10.
Science ; 368(6491): 642-648, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32273399

RESUMO

The structural complexity of composite biomaterials and biomineralized particles arises from the hierarchical ordering of inorganic building blocks over multiple scales. Although empirical observations of complex nanoassemblies are abundant, the physicochemical mechanisms leading to their geometrical complexity are still puzzling, especially for nonuniformly sized components. We report the self-assembly of hierarchically organized particles (HOPs) from polydisperse gold thiolate nanoplatelets with cysteine surface ligands. Graph theory methods indicate that these HOPs, which feature twisted spikes and other morphologies, display higher complexity than their biological counterparts. Their intricate organization emerges from competing chirality-dependent assembly restrictions that render assembly pathways primarily dependent on nanoparticle symmetry rather than size. These findings and HOP phase diagrams open a pathway to a large family of colloids with complex architectures and unusual chiroptical and chemical properties.

11.
J Ethnopharmacol ; 255: 112771, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32201300

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: As an important medicinal material constituting a variety of traditional Chinese medicine prescriptions, Nepeta angustifolia C. Y. Wu was used as a folk medicine to treat various vascular-related diseases including apoplexia, and cerebral haemorrhage in Tibet, China. Our previous studies have shown that this plant had a significant protective effect on vascular dysfunction of the intracerebral haemorrhage and diabetic rats. In present study, we aimed to investigate the protective effects and underlying mechanisms of Nepeta angustifolia on diabetic nephropathy (DN), a microvascular complication. AIM OF THE STUDY: This study is aim to evaluate the protective effect of ethanol extracts of N. angustifolia (NA) on DN, and explore mechanism of action to provide basis for its pharmacological action against DN. MATERIALS AND METHODS: High-fat diet and low-dose streptozotocin administration (HFD/STZ) induced diabetic rats were randomly divided into 5 groups (n = 8): the diabetic model group, metformin group, and three dose groups of NA (60 mg/kg, 120 mg/kg, 240 mg/kg). After administration of NA for 8 weeks, the blood, urine and renal tissue were collected for subsequent experiments. Biochemical markers (urine protein, Cr, BUN), oxidative stress makers (SOD, GSH-px and MDA) and pro-inflammatory mediators (TNF-α, IL-1ß, IL-6 and MCP-1) were evaluated by commercial kit and ELISA, respectively. The effect of NA on DN was further confirmed by evaluation of renal histopathology by using the H&E, PAS and Masson staining. The H2O2-induced HBZY-1 cells (rat glomerular mesangial cells) were also been used to evaluate the renal protective effect of NA (50 µg/mL, 100 µg/mL, 200 µg/mL). The oxidative stress makers were detected by commercial kit. The levels of apoptosis and related proteins (caspase 3, 9) were detected by TUNEL assay and western blot analysis, respectively. The depolarization of mitochondrial membrane potential was detected by JC-1 staining assay. RESULTS: The administration of NA is helpful to maintain near normal body weight, blood glucose, urine volume, urine protein, kidney index and serum levels of Cr and BUN. NA treatment significantly improve renal dysfunction by the down-regulation of renal oxidative stress and pro-inflammatory mediators in HFD/STZ induced diabetic rats. In vitro experiments, NA has a significant cellular protective effect in H2O2-induced HBZY-1 cells, as well as the regulation in increases of SOD level and the decreases of ROS and MDA levels. Furthermore, NA treatment can significantly inhibit H2O2 induced mesangial cells apoptosis by the increasing mitochondrial potential and suppressing caspases-madiated signaling pathway. CONCLUSIONS: NA has obvious improvement on renal dysfunction in HFD/STZ induced diabetic rats. NA can protect mesangial cells by inhibiting oxidative stress induced apoptosis, which may be related to its regulation of mitochondrial-caspase apoptosis pathway.

12.
Genes (Basel) ; 11(3)2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32106614

RESUMO

Tea (Camellia sinensis (L.) O. Kuntze) is a widely consumed beverage. Lack of macronutrients is a major cause of tea yield and quality losses. Though the effects of macronutrient starvation on tea metabolism have been studied, little is known about their molecular mechanisms. Hence, we investigated changes in the gene expression of tea plants under nitrogen (N), phosphate (P), and potassium (K) deficient conditions by RNA-sequencing. A total of 9103 differentially expressed genes (DEG) were identified. Function enrichment analysis showed that many biological processes and pathways were common to N, P, and K starvation. In particular, cis-element analysis of promoter of genes uncovered that members of the WRKY, MYB, bHLH, NF-Y, NAC, Trihelix, and GATA families were more likely to regulate genes involved in catechins, L-theanine, and caffeine biosynthetic pathways. Our results provide a comprehensive insight into the mechanisms of responses to N, P, and K starvation, and a global basis for the improvement of tea quality and molecular breeding.

13.
J Agric Food Chem ; 68(8): 2528-2538, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32011878

RESUMO

Albino became a novel kind of tea cultivar in China recently. In this study, transcriptome and whole-genome bisulfite sequencing (WGBS) were employed to investigate the shading effects on leaf color conversion and biosynthesis of three major secondary metabolites in the albino tea cultivar "Yujinxiang". The increased leaf chlorophyll level was likely the major cause for shaded leaf greening from young pale or yellow leaf. In comparison with the control, the total catechin level of the shading group was significantly decreased and the abundance of caffeine was markedly increased, while the theanine level was nearly not influenced. Meanwhile, differentially expressed genes (DEGs) enriched in some biological processes and pathways were identified by transcriptome analysis. Furthermore, whole-genome DNA methylation analysis revealed that the global genomic DNA methylation patterns of the shading period were remarkably altered in comparison with the control. In addition, differentially methylated regions (DMRs) and the DMR-related DEG analysis indicated that the DMR-related DEGs were the critical participants in biosynthesis of the major secondary metabolites. These findings suggest that DNA methylation is probably responsible for changes in the contents of the major secondary metabolites in Yujinxiang.


Assuntos
Camellia sinensis/metabolismo , Folhas de Planta/efeitos da radiação , Metabolismo Secundário/efeitos da radiação , Camellia sinensis/genética , Camellia sinensis/efeitos da radiação , Clorofila/biossíntese , Cor , Regulação da Expressão Gênica de Plantas , Luz , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Int J Biol Macromol ; 150: 122-128, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32045606

RESUMO

It is highly desirable to develop a facile approach for the detection of the human immunodeficiency virus (HIV). To address this need, an octopus-like DNA (OLD) is designed in a one-pot method by direct folding of nine short single strands of DNA (ssDNA), which can be used to capture all the conserved HIV-1 gene efficiently though the sticky arms. The branched OLD was applied for the enzyme-free detection of HIV-1 nucleic acid and the visualization of the virus during HIV infection. The total detection procedure can be finished within 2 h with high specificity, making the OLD system a valuable tool for the rapid detection of HIV virus and further biomedical application.

15.
Pharmacol Res ; 153: 104654, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31945473

RESUMO

Metabolic syndrome, such as diabetes mellitus, obesity, atherosclerosis, and high blood pressure (HBP), are closely linked pathophysiologically. However, current monotherapies for metabolic syndrome fail to target the multifactorial pathology via multiple mechanisms, as well as resolving the dysfunctionality of the cells and organs of the body. We aimed to provide a comprehensive and up-to-date review of the pharmacological advances, therapeutic potential, and phytochemistry of Salvia miltiorrhiza, Carthamus tinctorius, and Danhong injection (DHI). We discussed the molecular mechanisms of the bioactive constituents relating to diabetes mellitus and metabolic disease for further research and drug development. Interestingly, Salvia miltiorrhiza, Carthamus tinctorius, and DHI have anti-inflammatory, anti-glycemic, anti-thrombotic, and anti-cancer properties; and they mainly act by targeting the dysfunctional vasculatures including the inflammatory components of the disease to provide vascular repair as well as resolving oxidative stress. The major bioactive chemical constituents of these plants include polyphenolic acids, diterpene compounds, carthamin, and hydroxysafflor yellow A. Treatment of diabetes mellitus and its associated cardiovascular complication requires a comprehensive approach involving the use of appropriate traditional Chinese medicine formula. Danshen, Honghua, and DHI target the multiple risk factors regulating the physiologic function of the body and restore normalcy, apart from the traditional advice on exercise and diet control as treatment options in a metabolic syndrome patient.

16.
Int J Biol Macromol ; 149: 732-740, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31987946

RESUMO

The polysaccharides and phenylethanoid glycosides from Cistanche deserticola have been demonstrated with various health benefits, however the interactive effect between these two kinds of compounds in vivo are not in detail known. The objective of this study was to investigate the synergistic actions of cistanche polysaccharides with phenylethanoid glycoside and the effects of polysaccharides on gut microbiota. Sprague-Dawley rats were fed with different kinds of cistanche polysaccharides for 20 days, on the last day, all rats were administered the echinacoside at 100 mg/kg. The results were compared mainly on the difference of pharmacokinetic parameters, gut microbiota composition, and short chain fatty acids contents. The results indicated that all the cistanche polysaccharides, including crude polysaccharide, high molecular weight polysaccharide and low molecular weight polysaccharide, could regulate the gut microbiota diversity, increase beneficial bacteria and particularly enhance the growth of Prevotella spp. as well as improve the production of short chain fatty acids and the absorption of echinacoside. By exploring the synergistic actions of polysaccharides with small molecules, these findings suggest that cistanche polysaccharides, particularly low molecular weight polysaccharides, could be used as a gut microbiota manipulator for health promotion.

17.
Bioengineered ; 11(1): 103-115, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31903833

RESUMO

Abscisic acid (ABA) signaling regulates plant growth and development and participates in response to abiotic stressors. However, details about the PYL-PP2C-SnRK2 gene family, which is the core component of ABA signaling in Camellia sinensis, are unknown. In this work, we identified 14 pyrabactin resistance-likes (PYLs), 84 type 2C protein phosphatase (PP2Cs), and 8 SNF1-related protein kinase 2s (SnRK2s) from C. sinensis. The transcriptomic analysis indicated that PYL-PP2C-SnRK2s were associated with changes of leaf color and the response of C. sinensis to drought and salt stressors. Changes of the expression of Snrk2s were not significant in the process of leaf color change or drought and salt stress response, suggesting that PYLs and PP2Cs may not interact with SnRK2s in C. sinensis during these processes. Finally, Gene Regulatory Network (GRN) construction and interaction networks analysis demonstrated that PYLs and PP2Cs were associated with multiple metabolic pathways during the changes of leaf color.

18.
ACS Appl Mater Interfaces ; 12(4): 4212-4220, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31917546

RESUMO

As an invaluable tool for biomedical research, the green fluorescent proteins (GFPs) make tumor cells, amyloid plaques, and pathogenic bacteria equally visible. Here, inspired by the chromophore of GFPs, we constructed a tyrosine-based peptide that show green luminescence in the aggregation state. Similar to the optical property of GFPs, the tyrosine-based peptidyl nanoparticles are stabilized by intermolecular hydrogen bonding and emit fluorescence when the Tyr residues bear phenolic anions. In addition, the tyrosine-based peptide is cell-permeable and endosome-escaped when conjuncted with the GPGR motif of human immunodeficiency virus and can be used for stable cell imaging due to its excellent photostability, pH-sensitivity and biocompatibility in physiological conditions. The results provide a promising pathway to construct peptidyl bioluminescent agents for biomedical applications.


Assuntos
Nanopartículas/química , Peptídeos/química , Fluorescência , Proteínas de Fluorescência Verde/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Simulação de Dinâmica Molecular , Espectrometria de Fluorescência
19.
Bioresour Technol ; 295: 122250, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31629281

RESUMO

Increasing nitrogenous contaminants have caused immense challenges to the environment and human health. As compared to physical and chemical methods, biological denitrification is considered to be an effective solution due to its environmental friendliness, high efficiency, and low cost. In the present work, a novel fungal strain identified as Fusarium solani (RADF-77) was isolated from cellulose material-supported denitrification reactor; this strain is capable of removing nitrogen under aerobic conditions. The average NO3--N removal rate for RADF-77 were 4.43 mg/(L·h) and 4.50 mg/(L·d), when using glucose and tea residue as carbon source, respectively. The nitrogen balance revealed that 53.66% of N vanished via gaseous products. Transcriptional results revealed that respiratory and assimilative nitrate reductases may work together for nitrate removal. Our results indicate that RADF-77 could be used as a potential means of enhancing nitrate-removal performance, as well as recycling tea residue, which is the main byproduct of the manufacture of tea extracts.


Assuntos
Desnitrificação , Fusarium , Aerobiose , Nitratos , Nitrificação , Nitrogênio
20.
Nanoscale ; 12(3): 1406-1413, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31872830

RESUMO

Wide band gap semiconductors are promising UV photodetector materials due to their suitable bandgap, high crystal quality, strong absorption and large carrier mobility. Up to now, deep UV photodetectors are mainly based on epitaxial thin films, which have some undesired properties such as p-type doping difficulty. Lattice mismatch hinders the further development of these devices. Here, a high performance self-powered solar-blind UV photodetector was realized by a facile combination of a centimeter-sized single crystal ß-Ga2O3 microwire and polyaniline. Owing to the excellent organic/inorganic hybrid p-n junction, the device shows an ultrahigh responsivity of 21 mA W-1 at 246 nm with a sharp cut-off wavelength of 272 nm without an external power supply. Moreover, the dark current is 0.08 pA, which is smaller than those of almost all the previous metallic oxide based solar-blind UV photodetectors. The photodetector also shows a high UV/visible rejection ratio (102) at zero bias voltage. Finally, a physical model of the self-powered photodetector is also proposed. This work provides a simple, low-cost, and effective method for preparing high performance self-powered solar-blind UV photodetectors based on organic/inorganic heterojunctions.

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