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1.
Front Microbiol ; 14: 1287582, 2023.
Article in English | MEDLINE | ID: mdl-38075866

ABSTRACT

Introduction: Endophytic microorganisms are bacteria or fungi that inhabit plant internal tissues contributing to various biological processes of plants. Some endophytic microbes can promote plant growth, which are known as plant growth-promoting endophytes (PGPEs). There has been an increasing interest in isolation and identification of PGPEs for sustainable production of crops. This study was undertaken to isolate PGPEs from roots of a halophytic species Sesuvium portulacastrum L. and elucidate potential mechanisms underlying the plant growth promoting effect. Methods: Surface-disinfected seeds of S. portulacastrum were germinated on an in vitro culture medium, and roots of some germinated seedlings were contaminated by bacteria and fungi. From the contamination, an endophytic fungus called BF-F (a fungal strain isolated from bacterial and fungal contamination) was isolated and identified. The genome of BF-F strain was sequenced, its genome structure and function were analyzed using various bioinformatics software. Additionally, the effect of BF-F on plant growth promotion were investigated by gene cluster analyses. Results: Based on the sequence homology (99%) and phylogenetic analysis, BF-F is likely a new Cladosporium angulosum strain or possibly a new Cladosporium species that is most homologous to C. angulosum. The BF-F significantly promoted the growth of dicot S. portulacastrum and Arabidopsis as well as monocot rice. Whole genome analysis revealed that the BF-F genome has 29,444,740 bp in size with 6,426 annotated genes, including gene clusters associated with the tryptophan synthesis and metabolism pathway, sterol synthesis pathway, and nitrogen metabolism pathway. BF-F produced indole-3-acetic acid (IAA) and also induced the expression of plant N uptake related genes. Discussion: Our results suggest that BF-F is a novel strain of Cladosporium and has potential to be a microbial fertilizer for sustainable production of crop plants. The resulting genomic information will facilitate further investigation of its genetic evolution and its function, particularly mechanisms underlying plant growth promotion.

2.
Biosens Bioelectron ; 242: 115703, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37820556

ABSTRACT

We demonstrated a temperature-compensated optofluidic DNA biosensor available for microfluidic chip. The optofluidic sensor was composed of an interferometer and a fiber Bragg grating (FBG) by femtosecond laser direct writing micro/nano processing technology. The sensing arm of the interferometer was suspended on the inner wall of the microchannel and could directly interact with the microfluid. With the immobilization of the single stranded probe DNA (pDNA), this optofluidic biosensor could achieve specific detection of single stranded complementary DNA (scDNA). The experimental results indicated that a linear response within 50 nM and the detection limit of 1.87 nM were achieved. In addition, the optofluidic biosensor could simultaneously monitor temperature to avoid temperature fluctuations interfering with the DNA hybridization detection process. And, the optofluidic detection channel could achieve fast sample replacement within 10 s at a flow rate of 2 µL/min and sample consumption only required nanoliters. This optofluidic DNA biosensor had the advantages of label-free, good specificity, dual parameter detection, low sample consumption, fast response, and easy repeatable preparation, which was of great significance for the field of DNA hybridization research and solving the temperature sensitivity problem of biosensors and had good prospects in biological analysis.


Subject(s)
Biosensing Techniques , Microfluidics , Temperature , Biosensing Techniques/methods , Fiber Optic Technology , DNA/genetics , DNA/analysis , DNA, Single-Stranded
3.
J Hazard Mater ; 460: 132414, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37677970

ABSTRACT

3D printing waste (3DPW) contains hazardous substances, such as photosensitizers and pigments, and may cause environmental pollution when improperly disposed of. Pyrolysis treatment can reduce hazards and turn waste into useful resources. This study coupled thermogravimetric (TG), TG-Fourier transform infrared spectroscopy-gas chromatography/mass spectrometry, and rapid pyrolysis gas chromatography/mass spectrometry analysis to evaluate the pyrolytic reaction mechanisms, products, and possible decomposition pathways of the three typical 3DPW of photosensitive resin waste (PRW), polyamide waste (PAW), and polycaprolactone waste (PCLW). The main degradation stages of the typical 3DPW occurred at 320-580 °C. The most appropriate reaction mechanisms of PRW, PAW and PCLW were D1, A1.2 and A1.5, respectively. The main pyrolysis processes were the decomposition of the complex organic polymers of PRW, the breaking of the NH-CH2 bond and dehydration of -CO-NH- of PAW, and the breaking and reorganization of the molecular chains of PCLW, mainly resulting in toluene (C7H8), undecylenitrile (C11H21N), tetrahydrofuran (C4H8O), respectively. Unlike the slow pyrolysis, the rapid pyrolysis produced volatiles consisting mainly of phenol, 4,4'-(1-methylethylidene)bis- (C15H16O2) for PRW; 1,10-dicyanodecane (C12H20N2) for PAW; and ɛ-caprolactone (C6H10O2) for PCLW. These pyrolysis products hold great potential for applications. The findings of the study offer actionable insights into the hazard reduction and resource recovery of 3D printing waste.

4.
Anal Chem ; 95(33): 12532-12540, 2023 08 22.
Article in English | MEDLINE | ID: mdl-37553756

ABSTRACT

Rapid and sensitive antigen detection using a lateral flow immunoassay (LFIA) is crucial for diagnosing infectious diseases due to its simplicity, speed, and user-friendly features. However, it remains a critical issue to explore specific biorecognition elements and powerful signal amplification. In this study, taking SARS-CoV-2 as a proof of concept, a specific peptide, WFLNDSELIML, binding to the SARS-CoV-2 spike (S) antigen was identified by a nonamplified biopanning method, which exhibited high affinity to the target, with a dissociation constant of 9.29 ± 1.55 nM. Molecular docking analysis reveals that this peptide binds to the N-terminal domain of the SARS-CoV-2 S antigen. Then, using this peptide as a capture probe and angiotensin-converting enzyme 2 as a detection probe, a peptide-based lateral flow immunoassay (pLFIA) for the sensitive detection of the SARS-CoV-2 S antigen without any antibody was developed, for which a polydopamine nanosphere (PDA)@MnO2 nanocomposite with excellent oxidase-like activity was used as a colorimetric label, exhibiting dual-mode remarkable signal amplification of natural melanin and on-demand nanozyme catalytic enhancement. The PDA@MnO2-based pLFIA is capable of detecting the SARS-CoV-2 S antigen with a limit of detection of 8.01 pg/mL, which is 18.7 times lower than that of a conventional pLFIA tagged with gold nanoparticles. Additionally, the as-proposed PDA@MnO2-based pLFIA can detect up to 150 transduction units/mL SARS-CoV-2 pseudoviruses spiked in saliva samples. Given the outstanding analytical performance, the proposed PDA@MnO2-based pLFIA may offer a reliable option for the rapid diagnosis of SARS-CoV-2.


Subject(s)
Blood Group Antigens , COVID-19 , Metal Nanoparticles , Humans , COVID-19/diagnosis , Gold , Manganese Compounds , Molecular Docking Simulation , Oxides , SARS-CoV-2 , Immunoassay
5.
J Hazard Mater ; 459: 132190, 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37536156

ABSTRACT

Sulfidated zero-valent iron (S-ZVI) has shown significant potential for the removal of arsenic(III). However, little attention has been paid to the mechanism of As(III) sequestration enhancement and how the phase transformation for S-ZVI strengthens this process in aerobic conditions. In this work, sulfidated ZVI was created by ball-milling (S-ZVIbm) and liquid-mixing (S-ZVIlm) of ZVI with elemental sulfur(S0) to investigate the performance and mechanisms of As(III) sequestration in air-saturated water. Sulfidation was found to significantly enhance the As(III) removal rate constant, which was 2.8 âˆ¼ 6.7 times (S-ZVIbm) and 3.1 âˆ¼ 17.1 times (S-ZVIlm) higher than that without sulfidation. FeS was identified as the predominant sulfur species in the S-ZVI samples using S K-edge XANES spectra. The enhanced electron transfer and ZVI corrosion after sulfidation were verified via electrochemical tests. XANES and Mössbauer spectra suggested that lepidocrocite(γ-FeOOH) was the predominant corrosion product generated on the ZVI surface with the presence of oxygen, and DFT calculations further confirmed the improved performance of γ-FeOOH for As(III) sequestration. Besides, As(III) oxidation occurred dominantly on the heterogeneous surface rather than in solution, and the As(III) sequestration pathway of adsorption followed by oxidation was proposed. This study provides new insight into the enhanced As(III) sequestration by S-ZVI in aerobic conditions.

6.
Chempluschem ; 86(9): 1322-1341, 2021 09.
Article in English | MEDLINE | ID: mdl-34363342

ABSTRACT

Owing to the low price, chemical stability and good conductivity, carbon-based materials have been extensively applied as the anode in microbial fuel cells (MFCs). In this review, apart from the charge storage mechanism and anode requirements, the major work focuses on five categories of carbon-based anode materials (traditional carbon, porous carbon, nano-carbon, metal/carbon composite and polymer/carbon composite). The relationship is demonstrated in depth between the physicochemical properties of the anode surface/interface/bulk (porosity, surface area, hydrophilicity, partical size, charge, roughness, etc.) and the bioelectrochemical performances (electron transfer, electrolyte diffusion, capacitance, toxicity, start-up time, current, power density, voltage, etc.). An outlook for future work is also proposed.

7.
Opt Lett ; 46(13): 3069, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34197381

ABSTRACT

This publisher's note contains corrections to Opt. Lett.46, 2714 (2021).OPLEDP0146-959210.1364/OL.428001.

8.
Opt Lett ; 46(11): 2714-2717, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34061095

ABSTRACT

A special open-cavity Mach-Zehnder salinity sensor is presented and verified in this Letter, which has obvious advantages in salinity sensitivity and loss. The open-cavity structure is composed of a short section of etched double-side hole fiber spliced between a pair of multimode fibers and connected in series between a pair of single-mode fibers, which is the SMF-MMF-etched DSHF-MMF-SMF structure proposed in the paper. According to the experiment results, when the cavity length is about 100 µm, the salinity sensitivity of the sensing probe can reach 2 nm/‰, and its refractive index (RI) sensitivity can be more than 10,000 nm/RIU, while having a low loss of ${-}{15}\;{\rm dB}$ and a detection limit of 0.23‰. Based on its characteristics, the sensor is a prospective online monitor of ocean salinity. At the same time, it also provides a low-cost way to construct an open cavity instead of femtosecond inscribing.

9.
Ecotoxicol Environ Saf ; 211: 111914, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33454593

ABSTRACT

Bioremediation of Cd contaminated environments can be assisted by plant-growth-promoting bacteria (PGPB) enabling plant growth in these sites. Here a gram-negative Burkholderia contaminans ZCC was isolated from mining soil at a copper-gold mine. When exposed to Cd(II), ZCC displayed high Cd resistance and the minimal inhibitory concentration was 7 mM in LB medium. Complete genome analysis uncovered B. contaminans ZCC contained 3 chromosomes and 2 plasmids. One of these plasmids was shown to contain a multitude of heavy metal resistance determinants including genes encoding a putative Cd-translocating PIB-type ATPase and an RND-type related to the Czc-system. These additional heavy metal resistance determinants are likely responsible for the increased resistance to Cd(II) and other heavy metals in comparison to other strains of B. contaminans. B. contaminans ZCC also displayed PGPB traits such as 1-aminocyclopropane-1-carboxylate deaminase activity, siderophore production, organic and inorganic phosphate solubilization and indole acetic acid production. Moreover, the properties and Cd(II) binding characteristics of extracellular polymeric substances was investigated. ZCC was able to induce extracellular polymeric substances production in response to Cd and was shown to be chemically coordinated to Cd(II). It could promote the growth of soybean in the presence of elevated concentrations of Cd(II). This work will help to better understand processes important in bioremediation of Cd-contaminated environment.


Subject(s)
Adaptation, Physiological/physiology , Burkholderia/physiology , Cadmium/toxicity , Soil Pollutants/toxicity , Biodegradation, Environmental , Cadmium/metabolism , Indoleacetic Acids , Metals, Heavy/analysis , Mining , Plant Development , Soil/chemistry , Soil Microbiology , Soil Pollutants/analysis , Glycine max/metabolism
10.
Opt Lett ; 45(24): 6631-6634, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33325856

ABSTRACT

A multifunctional optical fiber sensor fabricated by asymmetric offset splicing is proposed in this Letter. The light is divided into several parts at the offset interface, among which the transmitted light forms the Mach-Zehnder interference (MZI) spectrum while the reflected light forms the Fabry-Perot interference (FPI) spectrum. The online monitoring system is built to create a better light distribution at the offset interface. Theoretical analysis and experimental verification are carried out. The results of the experiment show that the proposed sensor has good characteristics of salinity and temperature, and the salinity sensitivity is as high as -2.4473nm/‰ in the range of 20-40‰; the temperature sensitivity is better than 2.17 nm/°C in the range of 28-48 °C. The two interferometers involved have different responses to temperature and salinity, contributing to the effective elimination of cross-sensitivity. The proposed optical fiber sensor has the benefits of compact size, high sensitivity, and multispectral measurement function.

11.
Lab Chip ; 20(21): 4007-4015, 2020 11 07.
Article in English | MEDLINE | ID: mdl-32966477

ABSTRACT

Lung cancer is one of the leading causes of death worldwide. Fifteen percent of lung cancer patients will present with malignant pleural effusion initially, and up to 50% will have malignant pleural effusion throughout the course of the disease. In this study, we developed a spiral microfluidic device that can rapidly isolate cancer cells and improve their purity through fluid dynamics. This label-free, high-throughput device continuously isolates cancer cells and other unrelated molecules from pleural effusion. Most of the background cells that affect interpretation are flushed to outlets 1 to 3, and cancer cells are hydrodynamically concentrated to outlet 4, with 90% of lung cancer cells flowing to this outlet. After processing, the purity of cancer cells identified in pleural effusion by CD45 and epithelial cell adhesion molecule (EpCAM) antibodies in flow cytometry will be increased by 6 to 24 times. The microfluidic device presented here has the advantages of rapid processing and low cost, which are conducive to rapid and accurate clinical diagnosis.


Subject(s)
Lung Neoplasms , Pleural Effusion, Malignant , Pleural Effusion , Flow Cytometry , Humans , Lung Neoplasms/diagnosis , Microfluidics , Pleural Effusion/diagnosis , Pleural Effusion, Malignant/diagnosis
12.
Sci Total Environ ; 738: 140232, 2020 Oct 10.
Article in English | MEDLINE | ID: mdl-32806353

ABSTRACT

Antimony (Sb) is not an essential element for humans and plants although it can be used to treat some human diseases, such as schistosomiasis. Sb contamination has been documented in many regions around the world, particularly in China. The Sb contamination in the environment often stems from anthropogenic activities such as mining, smelting, and shooting. Within the latest decade, great progress has been made in research examining the physiochemical behavior of Sb in the environment, including 1) the extent of Sb pollution around the world particularly in China; 2) the mechanisms and factors influencing Sb migration in soils, especially the adsorption/desorption of Sb by minerals or organic materials; 3) the transformations influencing speciation catalyzed by soil microbes; 4) to a lesser extent, the toxicity of Sb to plants and soil animals. In this review, we highlighted the current knowledge with respect to 1) how soil physicochemical properties (including water regimes, pH, organic materials and Eh), and soil organisms will affect the soil bioavailability of Sb, and subsequently the uptake of Sb by plants; 2) the uptake pathway of antimonite and antimonate, the translocation of Sb from roots to shoots, and the redistribution and toxicity of Sb in plants.


Subject(s)
Antimony/analysis , Soil Pollutants/analysis , China , Environmental Monitoring , Soil
13.
Sci Total Environ ; 711: 134589, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32000315

ABSTRACT

Antimony (Sb) is a toxic element for both human and plants, but the toxic responses of plants to different forms of antimony and the associated mechanisms are unknown. This study was carried out to investigate the effects of different forms of Sb [Sb(III) and Sb(V)] on the root exudates, root endogenous hormones, root cell wall components and antioxidant systems in rice plant via three hydroponic experiments. The results showed that Sb(III) displayed a higher toxicity than Sb(V) to the plant which accumulated much more Sb in its tissues under Sb(III) exposure than that under Sb(V) exposure. Under Sb(III) exposure, most of absorbed Sb was found to be Sb(III) in the shoots and roots; however when plants were exposed to Sb(V), most of absorbed Sb in this rice plant was Sb(V). Only two kinds of endogenous hormones were detected as abscisic acid (ABA) and salicylic acid (SA). The addition of Sb(III) significantly increased the content of ABA but Sb(V) did not, probably suggesting the higher toxicity of Sb(III) than Sb(V) might be due to the stimulation of ABA content. The addition of Sb(III) significantly increased the concentration of oxalic acid but decreased the concentrations of formic, acetic and maleic acids. Sb(V) also enhanced the oxalic acid concentration at 20 mg L-1 Sb(V) treatment level but reduced the concentrations of formic and acetic acids. Different forms of Sb dose-dependently increased the content of pectin, but significantly enhanced the content of lignin in cell wall. Different forms of Sb induced oxidative stress, but rice plant triggered the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) to counteract the oxidative stress.


Subject(s)
Antimony , Oryza , Antioxidants , Cell Wall , Plant Roots
14.
Mater Sci Eng C Mater Biol Appl ; 100: 576-583, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30948094

ABSTRACT

Hydroxyapatite/sodium alginate/chitosan (HA/SA/CS) composite microspheres, which possess good biocompatibility for specific biomedical application, were prepared using an emulsion crosslink technique; calcium ions were used as a cross-linking agent. The effect of the concentration of sodium alginate (SA), the volume ratio of water to oil, the content of hydroxyapatite (HA) nanoparticles, as well as rotation speed, on the morphology and dispersion of composite microspheres were investigated. Also investigated were the drug loading, release behaviors, in vitro hemolysis activity, cytotoxicity, cell adhesion and proliferation capacity of the materials. The results demonstrate that the HA/SA/CS composite microspheres were successfully prepared; their drug loading and encapsulation efficiency are much higher than that of HA nanoparticles. Dox-loaded HA/SA/CS composite microspheres show good pH-sensitive drug-release capability. The hemolysis and cytotoxicity tests suggest that the microspheres have good blood and cell compatibility. Furthermore, the prepared composite microspheres display better cell adhesion and proliferation capacity than HA nanoparticles and HA/SA composite microspheres. Therefore, the HA/SA/CS composite microspheres might have potential as drug carriers in a pH-responsive controlled-release drug delivery system and as candidates for application in bone tissue engineering.


Subject(s)
Alginates/chemistry , Bone and Bones/physiology , Chitosan/chemistry , Drug Delivery Systems/methods , Durapatite/chemistry , Microspheres , Tissue Engineering/methods , Animals , Bone and Bones/drug effects , Cell Adhesion/drug effects , Cell Death/drug effects , Cell Line , Cell Proliferation/drug effects , Doxorubicin/pharmacology , Drug Liberation , Hemolysis/drug effects , Humans , Male , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Rabbits , Reference Standards , Spectroscopy, Fourier Transform Infrared , Surface Properties , X-Ray Diffraction
15.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3245, 2010 Nov 20.
Article in English | MEDLINE | ID: mdl-21589532

ABSTRACT

The asymmetric unit of the title compound, C(17)H(20)N(2), contains two mol-ecules, whose bond lengths and angles differ only slightly. In the crystal, neighbouring mol-ecules form pillar structures via edge-to-face π-π stacking inter-actions [edge-to-face distances = 3.538 (3) and 3.496 (3)Å].

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