MOLECULES
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2019
·Vol. 24
·期 5
·891
·
IF 3.06
Ye Liu,Jiaqi Liu,Renmei Zhang,Yan Guo,Hongbo Wang,Qingguo Meng,Yuan Sun,Zongliang Liu
3,4-dihydropyrimidin-2(1H)-one compounds (DHPMs) possess extensive biological activities and are mainly prepared via Biginelli reaction and N-alkylation. In the present study, selective alkylation of N1was investigated by using tetrabutylammonium hydroxide. In vitro cytotoxicity study on all synthesized compounds demonstrated that introduction of the aryl chain in the R3as well as the low electron-donating group in the R1of DHPMs contributed to the anti-proliferative potency. A larger value of the partition coefficient (Log P) and suitable polar surface area (PSA) values were both found to be important in order to maintain the antitumor activity. The results from in vivo study indicated the great potential of compound3dto serve as a lead compound for novel anti-tumor drugs to treat glioma. Pharmacophore study regarding the structure-activity relations of DHPMs were also conducted. Our results here could provide a guide for the design of novel bioactive 3,4-dihydropyrimidin-2(1H)-one compounds.Keywords:3,4-dihydropyrimidin-2(1H)-ones;N1-alkylation;structure-activity relationship;in vivo experiments;anticancer activities
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Microbial Cell Factories
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2019
·Vol. 18
·期 1
·1-10
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IF 4.402
Xu Jian-Miao,Li Jian-Qiang,Zhang Bo,Liu Zhi-Qiang,Zheng Yu-Guo
Background l -2-aminobutyric acid ( l -ABA) is an unnatural amino acid that is a key intermediate for the synthesis of several important pharmaceuticals. To make the biosynthesis of l -ABA environmental friendly and more suitable for the industrial-scale production. We expand the nature metabolic network of Escherichia coli using metabolic engineering approach for the production of l -ABA. Results In this study, Escherichia coli THR strain with a modified pathway for threonine-hyperproduction was engineered via deletion of the rhtA gene from the chromosome. To redirect carbon flux from 2-ketobutyrate (2-KB) to l -ABA, the ilvIH gene was deleted to block the l -isoleucine pathway. Furthermore, the ilvA gene from Escherichia coli W3110 and the leuDH gene from Thermoactinomyces intermedius were amplified and co-overexpressed. The promoter was altered to regulate the expression strength of ilvA* and leuDH . The final engineered strain E. coli THR Δ rhtA Δ ilvIH /Gap- ilvA *-Pbs- leuDH was able to produce 9.33 g/L of l -ABA with a yield of 0.19 g/L/h by fed-batch fermentation in a 5 L bioreactor. Conclusions This novel metabolically tailored strain offers a promising approach to fulfill industrial requirements for production of l -ABA.
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COLORATION TECHNOLOGY
·
2019
·Vol. 135
·期 5
·335-348
·
IF 1.241
Qiushui Zhang,Wei Xiong,Shufen Zhang,Wei Ma,Bingtao Tang
A new kind of hetero-bifunctional reactive dye containing 2-ethoxy-4-chloro- s -triazine, with better activity matching with β-hydroxyethyl sulphone sulphate at a low fixation temperature, was successfully synthesised and characterised. An ethoxy group was designed to be introduced into triazine to increase the substantivity and the reactivity of the dyes. Thereby, the fixation of mono- s -chlorotriazine/hydroxyethyl sulphone sulphate (KM-type) bifunctional reactive dyes on cotton was improved, and dyeing under mild conditions with high fixation was realised. Nineteen dyes with orange, red and blue colours were synthesised and characterised by UV-Vis and infrared spectroscopy and mass spectrometry. Synthesised dyes were dyed at 60, 75 and 90°C, respectively. Exhaustion and reactivity for all of the ethoxy-containing KM-type dyes was over 90% at the optimal temperature, and fixation was over 87%, which was higher than the ethoxy-free comparative dyes. The optimal fixation temperature of ethoxy-containing dyes was initially reduced to 75°C, and then to 60°C. Compared with comparative dyes, the wash fastness and light fastness were basically unchanged, and the wet rub fastness of the H-acid series was reduced by one grade.
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MICROCHIMICA ACTA
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2019
·Vol. 186
·期 7
·1-9
·
IF 5.479
Yu Qiongqiong,Liu Jing,Zhao Guangying,Dou Wenchao
An immunochromatographic assay (ICA) is presented that can be applied to simultaneous detection of clenbuterol (CLE) and ractopamine (RAC). It is making use of two red and blue silica nanoparticles (SiNPs) that act as labels for encoding the antibodies. This design permits multiplexed analysis in a single test line and does not require an external source for photoexcitation. Anti-CLE was labeled with red SiNPs, and anti-RAC with blue SiNPs. The capture antigens CLE-BSA and RAC-BSA were placed onto the conjugate pad and the test line of the test strip, respectively. Under bare eye examination, no cross-colored lines or nonspecific bioconjugate adsorption were observed, and the visible limit of detections for CLE (red) and RAC (blue) are 3 and 2 ng‧mL −1 , respectively. This design allows for multiplexed detection with reduced device dimensions and costs, and with easy integration and manufacturing. Conceivably, the method may be extended to simultaneous determination of numerous other analytes.
The principle of qualitative detection strategy of multiplex immunochromatographic assay for clenbuterol (CLE) and ractopamine (RAC) is schematically illustrated. Depending on the type and ratio of organic dyes, the color of colored silica nanoparticle can be tuned from red to purple and even to black (lower right corner).
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ACS Omega
·
2019
·
IF 2.584
Xinru Mu,Ganyu Zhu,Xu Li,Shaopeng Li,Xiaokang Gong,Huiquan Li,Guoxin Sun
Wet-process phosphoric acid is a fundamental process in the fertilizer industry. The influence of impurities on crystallization kinetics of CaSO4 was investigated in the Ca(H2PO4)2–H2SO4–H3PO4–H2O system using a mixed suspension mixed product removal crystallizer. Effects of Si, Al, Fe, Mg, K, and Na on crystal morphology and structure were examined in the highly acidic system through scanning electron microscopy and high-resolution transmission electron microscopy. Results show that the increase of Mg, K, and Na content facilitates crystal growth. Si, Al, and Fe are beneficial to CaSO4 crystal growth at a certain concentration range. Impurities also affect the crystal morphology, and the addition of Si, Fe, and Na promotes the formation of needle-like crystals compared with other impurities. X-ray diffraction results show that the preferred crystal growth direction is (020), and the interplanar spacing of the crystals is affected by the element radius of the impurities.
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BIOTECHNOLOGY AND APPLIED BIOCHEMISTRY
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2019
·Vol. 67
·期 3
·343-353
·
IF 1.559
Hai-Feng Hu,Hai-Yan Zhou,Gao-Ping Cheng,Ya-Ping Xue,Yuan-Shan Wang,Yu-Guo Zheng
R -2-(4-hydroxyphenoxy)propionicacid (HPOPA) is a valuable intermediate for the synthesis of enantiomerically pure aryloxyphenoxypropionic acid herbicides. In this work, to improve the HPOPA biosynthesis by Beauveria bassiana ZJB16002 from the substrate R -2-phenoxypropionic acid (POPA), the original HPOPA producer B. bassiana ZJB16002 was subjected to physical mutagenesis with 137 Cs-γ irradiation and chemical mutagen N -methyl- N' -nitro- N -nitrasoguanidine (NTG) induced mutagenesis. The effects of different treatment doses of the mutagens on the lethal rate and positive mutation rate were investigated, and the results showed that the optimal 137 Cs-γirradiation dose and NTG concentration was 850 Gy and 500 µg/mL, respectively. Under these conditions, a mutant strain CCN-7 with the highest HPOPA production capacity was obtained through two rounds of 137 Cs-γ irradiation treatment followed by one round of NTG mutagenesis. At the substrate (POPA) concentration of 50 g/L, HPOPA titer of CCN-7 reached 36.88 g/L, which was 9.73-fold higher than the parental strain. The morphology of the wild-type and mutant strain was compared and the results might provide helpful information in exploration of the correlation of morphology and biochemical features of B. bassiana .
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JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
·
IF 6.361
Chunyu Qiu,Fuxian Cai,Yuan Wang,Yijun Liu,Qingxiang Wang,Chuan Zhao
It is a highly desired yet challenging task to replace rare and expensive noble metal catalysts with inexpensive and earth-abundant metal ones in electrochemical sustainable chemistry field. Herein, the bimetallic zinc-cobalt layered double hydroxide nanosheets (ZnCo-LDH NS) have been facilely synthesized using 2-methylimidazole as a bifunctional alkali source (OH − ) and a morphological controlling reagent by the one-step room-temperature reaction. The mechanism study shows that the weak organic base of 2-methylimidazole-induced slow release of OH − in water/ethanol is the controlling factor for the formation of the LDH nanosheets. The ZnCo-LDH NS modified on glassy carbon electrode exhibited an overpotential of 385 mV at 10 mA cm −2 and a Tafel slope of 108 mV dec −1 in 1.0 M KOH for oxygen evolution reaction , outperforming the corresponding the monometal oxides of Zn-OH, Co-OH, the NaOH produced ZnCo-LDH microparticles , and even the benchmark catalyst of RuO 2 at high current density. Characterization experiments indicated that the outstanding electrocatalytic activity can be ascribed to the nanosheet-induced surface area effect, excellent electronic conductivity, and the coupling effect between Zn 2+ and Co 2+ in the material. This work offers a facile and environmental-friendly method for synthesising LDH nanosheets bearing enhanced oxygen evolution reaction activity.
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JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
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2019
·Vol. 19
·期 11
·7178-7184
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IF 1.093
Xing Xuteng,Wang Jihui,Li Qiushi,Hu Wenbin
Halloysite nanotubes (HNTs) are natural clay minerals with a tubular structure. They have attracted considerable attention as a potential nanocontainer due to their abundance, biocompatibility and nontoxicity. In this study, HNTs were handled with H2SO4 at 70 °C.
The morphology and structure of these acid-treated and original HNTs were investigated by scanning electron microscopy (SEM), energy dispersion spectrum (EDS), transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), and their specific
surface area was determined by automatic gas adsorption analyzer. The loading efficiency and release behavior of acid-treated HNTs for 2-Mercaptobenzothiazole (MBT) were investigated by UV-vis spectrophotometer. Results show that acid-treated HNTs retained their tubular structure, but their
internal diameter expanded by 35–37 nm after 32 h of acid treatment. After 72 h of acid treatment, HNTs can be transferred into amorphous silica nanotubes. Moreover, the specific surface area of these HNTs samples initially increased with the increase in acid treatment time but then
started to decrease after 32 h. The specific surface area of acid-treated HNTs at 32 h can reach 251.6 m2/g, which was much higher than that for untreated HNTs (55.3 m2/g). In addition, the loading capacity of acid-treated HNTs can reach 32.1% for HNTs-32, which is about
three times higher than that of original HNTs. The acid treatment has slight effect on the release behavior.
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INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
·
IF 3.375
Honghua Zhang,Jiakuo Xu,Hongguo Tang,Zhiqiang Yang,Ruixia Liu,Suojiang Zhang
Different metal compositions based on metal-ion-modified X-type zeolite in the isobutane/2-butene alkylation reaction were investigated. Bimetallic (rare earth (RE) and Cu) supported zeolites catalysts owned better lifetime and selectivity than those modified by the single metal (La, Ce, or Cu). CuLaX performed best with a 15 h catalytic lifetime obtained after hydrogen activation when the content of copper was 0.197 mmol/g. The possible reason is that the RE X-type catalyst modified with copper ion increases the concentration of strong Brønsted acid sites, which is more favorable for the hydride transfer in the alkylation. Herein, the valence of copper ions is of importance to the alkylation performance. A mechanism was proposed wherein the existence of Cu+ inhibited the progress of the oligomerization reaction and then prolonged the lifetime of the catalyst through decreasing the desorption concentration of 2-butene in the active site.
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ASIAN JOURNAL OF ANDROLOGY
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2018
·
IF 3.259
Guo-Tao Chen,Bai-Bing Yang,Jian-Huai Chen,Zheng Zhang,Lei-Lei Zhu,He-Song Jiang,Wen Yu,Yun Chen,Yu-Tian Dai
Erectile dysfunction (ED) associated with type 2 diabetes is a severe problem that requires effective treatment. Pancreatic kininogenase (PK) has the potential to improve the erectile function of ED patients. This study aims to investigate the effect of PK on erectile function in streptozotocin-induced type 2 diabetic ED rats. To achieve this goal, we divided male Sprague–Dawley rats into five groups. One group was not treated, and the other four groups were treated with saline, sildenafil, PK or sildenafil, and PK, respectively, for 4 weeks after the induction of type 2 diabetic ED. Then, intracavernous pressure under cavernous nerve stimulation was measured, and penile tissue was collected for further study. Endothelial nitric oxide synthase levels, smooth muscle content, endothelium content, cyclic guanosine monophosphate (cGMP) levels in the corpus cavernosum, and neuronal nitric oxide synthase levels in the dorsal penile nerve were measured. Improved erectile function and endothelium and smooth muscle content in the corpus cavernosum were observed in diabetic ED rats. When treating diabetic ED rats with PK and sildenafil at the same time, a better therapeutic effect was achieved. These data demonstrate that intraperitoneal injection of PK can improve erectile function in a rat model of type 2 diabetic ED. With further research on specific mechanisms of erectile function improvement, PK may become a novel treatment for diabetic ED.
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BIOCHEMICAL PHARMACOLOGY
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2018
·
IF 4.235
Mengjing Zhao,Tianpeng Zhang,Fangjun Yu,Lianxia Guo,Baojian Wu
Carboxylesterases (CES) are a family of phase I enzymes that play an important role in xenobiotic clearance and lipid metabolism. Here, we investigate a potential role of E4 promoter-binding protein 4 (E4bp4) in regulation of Ces and CPT-11 (irinotecan, a first-line drug for treating colorectal cancer) pharmacokinetics in mice. Mouse hepatoma Hepa-1c1c7 cells were transfected with Rev-erbα expression plasmid or siRNA targeting E4bp4. The relative mRNA and protein levels of Ces enzymes in the cells or the livers of wild-type and E4bp4-deficient (E4bp4 −/− ) mice were determined by qPCR and Western blotting , respectively. Transcriptional regulation of Ces by E4bp4/Rev-erbα were investigated using luciferase reporter, mobility shift, and co-immunoprecipitation (Co-IP) assays. Pharmacokinetic studies were performed with wild-type and E4bp4 −/− mice after intraperitoneal injection of CPT-11. E4bp4 ablation down-regulated an array of hepatic Ces genes in mice. E4bp4 −/− mice also showed reduced Ces-mediated metabolism and elevated systemic exposure of CPT-11, a well-known Ces substrate. Consistently, E4bp4 knockdown reduced the expression of Ces genes ( Ces2b , Ces2e and Ces2f ) in Hepa-1c1c7 cells. Furthermore, Rev-erbα repressed the transcription of Ces2b, whereas E4bp4 antagonized this repressive action. Co-IP experiment confirmed a direct interaction between E4bp4 and Rev-erbα. Through a combination of promoter analysis and mobility shift assays, we demonstrated that Rev-erbα trans-repressed Ces (Ces2b) through its specific binding to the -767 to-754 bp promoter region. In conclusion, E4bp4 regulates Ces enzymes through inhibition of the transrepression activity of Rev-erbα, thereby impacting the metabolism and pharmacokinetics of Ces substrates.
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NEW JOURNAL OF CHEMISTRY
·
2018
·Vol. 42
·期 16
·13375-13381
·
IF 3.201
Haobo Han,Wenqi Chen,Jiebing Yang,Jiayuan Zhang,Quanshun Li,Yan Yang
The modification of 2-amino-6-chloropurine on polyamidoamine was performed to synthesize a derivative, AP-PAMAM, which was then employed as a carrier for p53 gene delivery to achieve anti-tumor efficacy. Using a human prostate tumor cell line PC-3 as a model, enhanced expression level of p53 gene could be detected by RT-PCR, qPCR and western blotting. Based on the successful p53 gene transfection, an obvious anti-proliferative effect could be obtained, which was identified to be associated with the simultaneous induction of cell apoptosis and cell cycle arrest at the G1 phase. The cell apoptosis was elucidated to be triggered by the activation of the mitochondria-dependent apoptotic signaling pathway. In addition, AP-PAMAM/p53 transfection could restrain the migration of tumor cells as demonstrated by wound healing and Transwell migration assays. Notably, AP-PAMAM-mediated p53 delivery exhibited a stronger inhibitory effect on both cell proliferation and migration than the PAMAM/p53 group. In summary, AP-PAMAM/p53 transfection provided a promising route to achieve the p53-based gene therapy.
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