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Anthocyanin is an essential pigment in all major horticultural crops especially in ornamental trees. Magnolia wufengensis (new species of Magnolia) with red color flower was recently found as a popular species for ornamental use, but anthocyanin synthesis and regulation in M. wufengensis are poorly understood. Herein, transcriptome analysis was used to decipher the gene network associated with anthocyanin biosynthesis. An R2R3-like MwMYB-1 transcription factor was found. MwMYB-1 overexpression resulted in anthocyanin accumulation in tobacco and Arabidopsis. MwMYB-1 worked independently rather than forming a protein complex with bHLH or WD40 protein. According to MwMYB-1 DAP-seq analysis in Arabidopsis, the MwMYB-1 transcription factor preferred to bind the "AAGAGAG" motif (DREME-5) in the third exon of the AtMYB75 gene. The yeast one hybrid assay and transcription activity assay further confirmed this. Thus, MwMYB-1 activated AtMYB75 gene expression and conducted cascade amplification of anthocyanin biosynthesis. Taken together, our findings provide a novel understanding of anthocyanin biosynthesis regulation in M. wufengensis and can be used to promote agronomic trait improvement in tree species. • MwMYB-1 is a R2R3-like transcription factor in Magnolia wufengensis. • MwMYB-1 prefers to bind the "AAGAGAG" motif in the third exon of the MYB75 gene. • MYB75 gene is the target of MwMYB-1 in anthocyanin synthesis regulation. [ABSTRACT FROM AUTHOR]

The Bi 2 WO 6 was prepared by the hydrothermal method and its sonocatalytic activity was studied in the degradation of methyl orange (MO) solutions. The effects of catalytic activity of Bi 2 WO 6 on dye were inspected by the change in absorbance of dye with UV–vis spectrometer. The influences of operational parameters such as the addition amount of Bi 2 WO 6 , pH, the initial concentration of dyes, ultrasonic power and irradiation time on the degradation ratio were investigated. In addition, the obtained results indicated that the kinetics of sonochemical reactions of MO were consistent with the pseudo first-order kinetics and Bi 2 WO 6 had excellent reusability and stability during the sonochemical degradation processes. The generation and kinds of reactive oxygen species (ROS) and their influence on the sonochemical degradation of MO were determined by the methods of oxidation–extraction spectrophotometry and ROS scavengers. The results indicate that the degradation of MO in the presence of Bi 2 WO 6 under ultrasonic irradiation is related to the generation of ROS, in which both singlet molecular oxygen ( 1 O 2 ) and hydroxyl radical ( OH) play important roles in the sonochemical degradation of MO. These experimental results provide a sound foundation for the further development of Bi 2 WO 6 as a sonocatalyst in wastewater treatment. [ABSTRACT FROM AUTHOR]

Three different microstructures with line pattern, grid pattern, and spot pattern were fabricated on titanium surfaces by nanosecond laser. Scanning electron microscopy (SEM), contact angle measurement, surface roughness gage, and X-ray photoelectron spectroscopy (XPS) analyses were used to characterize and measure the surface morphology, contact angle, surface roughness, and chemical composition of titanium after laser processing. The results indicate that the contact angle of titanium surface is 77.8° immediately after laser processing, which shows hydrophilicity, and the contact angle presents a rising tendency with time in general. At steady state, the maximum contact angles for line pattern, grid pattern, and spot pattern increased to 157.2°, 153°, and 132.5°, respectively. It can be found that the surface wettability has changed from hydrophilicity to hydrophobicity and even to superhydrophobicity. The influence of surface morphology on the surface wettability effects immediately after laser treatment and does not change with time, while the effect of surface chemical composition on the surface wettability will continue from the beginning of laser processing to the stabilization of surface chemical composition. Finally, it can be deduced that the accumulation of carbon on the surface is probably the critical factor to improve the surface hydrophobicity. Therefore, it is concluded that laser-induced modification of surface wettability correlates with surface morphology and surface chemical composition. [ABSTRACT FROM AUTHOR]

Fluorescence, absorption, time-correlated single photon counting (TCSPC), and circular dichroism (CD) spectroscopic techniques as well as molecular modeling methods were used to study the binding characterization of promethazine (PMT) to human serum albumin (HSA) and the influence of flavonoids, rutin and baicalin, on their affinity. The results indicated that the fluorescence quenching mechanism of HSA by PMT is a static quenching due to the formation of complex. The reaction was spontaneous and mainly mediated by hydrogen bonds and hydrophobic interactions. The binding distance between the tryptophan residue of HSA and PMT is less than 8 nm, which indicated that the energy transfer from the tryptophan residue of HSA to PMT occurred. The binding site of PMT on HSA was located in sites I and the presence of PMT can cause the conformational changes of HSA. There was the competitive binding to HSA between PMT and flavonoids because of the overlap of binding sites in HSA. The flavonoids could decrease the association constant and increase the binding distance. In addition, their synergistic effect can further change the conformation of HSA. The decrease in the affinities of PMT binding to HSA in the presence of flavonoids may lead to the increase of free drug in blood, which would affect the transportation or disposition of drug and evoke an adverse or toxic effect. Hence, rationalising dosage and diet regimens should be taken into account in clinical application of PMT. [ABSTRACT FROM AUTHOR]

In this work, bovine serum albumin (BSA) and eosine B (EB) were selected as a model protein and sonosensitizer, respectively. The sonodynamic damage to protein in the presence of EB and its mechanism were studied by means of absorption and fluorescence spectra. The results indicated that the synergistic effects of ultrasound and EB can efficiently damage the BSA molecules, and the damage of protein could be mainly due to the generation of reactive oxygen species (ROS). The damage degree of protein increased with the increase of ultrasonic time and EB concentration because of the increased quantities of ROS. Hydroxyl free radical ( OH) was the major mediators of the ultrasound-inducing proteins damage in the presence of EB. In addition, the quantities of ROS from the diphenylcarbazide (DPCI)–EB solutions and the DPCI–fluorescein (FS) solutions with or without ROS scavengers were contrasted, respectively. The results show that FS mainly produce OH, but the quantities of ROS in the presence of FS were lower than those of EB, which indicates that the nitro and bromine substituent groups on the benzene ring of FS increase the quantity of ROS, but do not change the kinds of ROS. [ABSTRACT FROM AUTHOR]