7 research outputs found
Highly Selective Hydrogenation of Furfural to Cyclopentanone over a NiFe Bimetallic Catalyst in a Methanol/Water Solution with a Solvent Effect
The
aqueous phase hydrogenation of furfural to cyclopentanone over
a NiFe bimetallic catalyst was investigated for the efficient utilization
of biomass-derived compounds. Catalyst characterization by XRD, EDS
mapping, and TPR revealed significant synergetic effects in the NiFe/SBA-15
catalyst. With NiFe/SBA-15, cyclopentanone selectivity was increased
to 78.4% from 46.1% with Ni/SBA-15. The use of different supports
showed that weak acidity favors cyclopentanone formation. The solvent
played an important role: methanol/water solutions with different
compositional ratios gave significantly changed product distributions.
With pure methanol, and methanol-dominated and water-dominated solutions,
respectively, the main product was furfuryl alcohol, tetrahydrofurfuryl
alcohol, and cyclopentanone. Furfural in the water inhibited THFA
formation, which led furfural to preferentially produce cyclopentanone.
At the optimized reaction temperature, NiFe/SBA-15 in water gave 99.8%
furfural conversion and 90% cyclopentanone yield at 300 min, which
was much better than most reported nonprecious metal catalysts
Fluorescence and Colorimetric Dual-Mode Ratiometric Sensor Based on Zr–Tetraphenylporphyrin Tetrasulfonic Acid Hydrate Metal–Organic Frameworks for Visual Detection of Copper Ions
As
a special heavy metal ion, copper ions (Cu2+) play
an indispensable role in the fields of environmental protection and
safety. Their excessive intake not only easily leads to diseases but
also affects human health. Therefore, it is particularly important
to construct a facile, effective, and highly selective Cu2+ probe. Herein, a novel Zr–tetraphenylporphyrin tetrasulfonic
acid hydrate (TPPS) metal–organic framework (ZTM) was fabricated
using TPPS as the ligand and exhibited strong red fluorescence with
a high quantum yield of 12.22%. In addition, we designed a ratiometric
fluorescent probe by introducing green fluorescein isothiocyanate
(FITC), which was not subject to environmental interference and had
high accuracy. When exposed to different amounts of Cu2+, the fluorescence emission at 667 nm from ZTMs is remarkably quenched,
while that at 515 nm from FITC is enhanced, accompanied by a change
in the solutions’ fluorescence color from red to green under
a UV lamp. Besides, the ZTMs solutions display an excellent ratiometric
colorimetric response for Cu2+ and produce an obvious color
change (from green to colorless) that is visible to the naked eye.
The fabricated ZTMs@FITC fluorescent probe exhibits distinguished
performance for Cu2+ detection with linear ranges of 0.1
to 5 μM and 5 to 50 μM, as well as a low detection limit
of 5.61 nM. Moreover, a colorimetric sensor based on ZTMs exhibits
a good linear range from 0.1 to 20 μM for Cu2+ with
the detection limit of 4.96 nM. Furthermore, the dual-signal ratiometric
sensor has significant specificity for Cu2+ and is successfully
applied for monitoring Cu2+ in water samples, which proves
its practical application value in the environment and biological
systems
Data_Sheet_1_Cotton miR319b-Targeted TCP4-Like Enhances Plant Defense Against Verticillium dahliae by Activating GhICS1 Transcription Expression.ZIP
Teosinte branched1/Cincinnata/proliferating cell factor (TCP) transcription factors play important roles in plant growth and defense. However, the molecular mechanisms of TCPs participating in plant defense remain unclear. Here, we characterized a cotton TCP4-like fine-tuned by miR319b, which could interact with NON-EXPRESSER OF PATHOGEN-RELATED GENES 1 (NPR1) to directly activate isochorismate synthase 1 (ICS1) expression, facilitating plant resistance against Verticillium dahliae. mRNA degradome data and GUS-fused assay showed that GhTCP4-like mRNA was directedly cleaved by ghr-miR319b. Knockdown of ghr-miR319b increased plant resistance to V. dahliae, whereas silencing GhTCP4-like increased plant susceptibility by the virus-induced gene silencing (VIGS) method, suggesting that GhTCP4-like is a positive regulator of plant defense. According to the electrophoretic mobility shift assay and GUS reporter analysis, GhTCP4-like could transcriptionally activate GhICS1 expression, resulting in increased salicylic acid (SA) accumulation. Yeast two-hybrid and luciferase complementation image analyses demonstrated that GhTCP4-like interacts with GhNPR1, which can promote GhTCP4-like transcriptional activation in GhICS1 expression according to the GUS reporter assay. Together, these results revealed that GhTCP4-like interacts with GhNPR1 to promote GhICS1 expression through fine-tuning of ghr-miR319b, leading to SA accumulation, which is percepted by NPR1 to increase plant defense against V. dahliae. Therefore, GhTCP4-like participates in a positive feedback regulation loop of SA biosynthesis via NPR1, increasing plant defenses against fungal infection.</p
Dual-Modal Immunochromatographic Test for Sensitive Detection of Zearalenone in Food Samples Based On Biosynthetic Staphylococcus aureus-Mediated Polymer Dot Nanocomposites
The
rapid detection of toxins is of great significance to food
security and human health. In this work, a dual-modality immunochromatographic
test (DICT) mediated by Staphylococcus aureus (SA)-biosynthesized polymer dots (SABPDs) was constructed for sensitive
monitoring of zearalenone (ZEN) in agro products. The SABPDs as potent
microorganism nanoscaffolds with excellent solubility, brightness,
and stability were ingeniously fabricated employing hydroquinone and
SA as precursors in the Schiff base reaction and a self-assembly technique.
Thanks to the fact that they not only preserved an intact microsphere
for loading Fc regions of monoclonal antibodies (mAbs) and the affinity
of their labeled mAbs to antigen but also generated superb colorimetric–fluorescent
dual signals, the versatile SABPDs manifested unique possibilities
as the new carriers for dual-readout ICT with remarkable enhancement
in sensitivity in ZEN screening (limit of detection = 0.036 ng/mL,
which was 31-fold lower than that of traditional gold nanoparticle-based
ICT). Ultimately, the proposed immunosensor performed well in millet
and corn samples with satisfactory recoveries, demonstrating its potential
for point-of-care testing. This work offers a bio-friendly strategy
for biosynthesizing cell-based PD vehicles with bimodal signals for
food safety analysis
Ultrabright Fluorescent Nanorod-Based Immunochromatographic with Low Background for Advancing Detection Performance
Nanomaterials-based immunochromatographic
assays (ICAs) are of
great significance in point-of-care testing (POCT), yet it remains
challenging to explore low background platforms and high chromogenic
intensity probes to improve detection performance. Herein, we reported
a low interference and high signal-to-noise ratio fluorescent ICA
platform based on ultrabright persistent luminescent nanoparticles
(PLNPs) Zn2GeO4: Mn, which could produce intense
photoluminescence at 254 nm excitation to reduce background interference
from ICA substrates and samples. The prepared immunosensor was successfully
applied in T-2 toxin detection with a remarkable limit of detection
of 0.025 ng/mL, which was 22-fold more sensitive compared with that
of traditional gold nanoparticles. Ultimately, a portable 3D-printed
detection device equipped with a smartphone analyzing application
was fabricated for quantitative readout in POCT, achieving favorable
recoveries in practical sample detection. This work provides a creative
attempt for ultrabright PLNP-based low background ICA, and it also
guarantees its feasibility in practical POCT
Data_Sheet_1_A Cotton Lignin Biosynthesis Gene, GhLAC4, Fine-Tuned by ghr-miR397 Modulates Plant Resistance Against Verticillium dahliae.pdf
Plant lignin is a component of the cell wall, and plays important roles in the transport potential of water and mineral nutrition and plant defence against biotic stresses. Therefore, it is necessary to identify lignin biosynthesis-related genes and dissect their functions and underlying mechanisms. Here, we characterised a cotton LAC, GhLAC4, which participates in lignin biosynthesis and plant resistance against Verticillium dahliae. According to degradome sequencing and GUS reporter analysis, ghr-miR397 was identified to directedly cleave the GhLAC4 transcript through base complementary. GhLAC4 knockdown and ghr-miR397 overexpression significantly reduced basal lignin content compared to the control, whereas ghr-miR397 silencing significantly increased basal lignin levels. Based on staining patterns and GC/MS analysis, GhLAC4 acted in G-lignin biosynthesis. Under V. dahliae infection, we found that G-lignin content in ghr-miR397-knockdowned plants significantly increased, compared to these plants under the mock treatment, while G-lignin contents in GhLAC4-silenced plants and ghr-miR397-overexpressed plants treated with pathogen were comparable with these plants treated with mock, indicating that GhLAC4 participates in defence-induced G-lignin biosynthesis in the cell wall. Knockdown of ghr-miR397 in plants inoculated with V. dahliae promoted lignin accumulation and increased plant resistance. The overexpression of ghr-miR397 and knockdown of GhLAC4 reduced lignin content and showed higher susceptibility of plants to the fungal infection compared to the control. The extract-free stems of ghr-miR397-knockdowned plants lost significantly less weight when treated with commercial cellulase and V. dahliae secretion compared to the control, while the stems of ghr-miR397-overexpressed and GhLAC4-silenced plants showed significantly higher loss of weight. These results suggest that lignin protects plant cell walls from degradation mediated by cellulase or fungal secretions. In summary, the ghr-miR397-GhLAC4 module regulates both basal lignin and defence-induced lignin biosynthesis and increases plant resistance against infection by V. dahliae.</p
