363 results on '"Zhong, Tao"'
Search Results
2. Role of Additives in Electrochemical Deposition of Ternary Metal Oxide Microspheres for Supercapacitor Applications
- Author
-
Avijit Biswal, Prasanna Kumar Panda, Achyuta Nanda Acharya, Subhashree Mohapatra, Nibedita Swain, Bankim Chandra Tripathy, Zhong-Tao Jiang, and Manickam Minakshi Sundaram
- Subjects
Chemistry ,QD1-999 - Published
- 2020
- Full Text
- View/download PDF
3. Catalytic Hydrogenation of p‑Chloronitrobenzene to p‑Chloroaniline Mediated by γ‑Mo2N
- Author
-
Zainab N. Jaf, Mohammednoor Altarawneh, Hussein A. Miran, Mansour H. Almatarneh, Zhong-Tao Jiang, and Bogdan. Z. Dlugogorski
- Subjects
Chemistry ,QD1-999 - Published
- 2018
- Full Text
- View/download PDF
4. Design, Synthesis, and Biological Evaluation of Novel Biotinylated Podophyllotoxin Derivatives as Potential Antitumor Agents
- Author
-
Cheng-Ting Zi, Ying-Sheng Gao, Liu Yang, Shu-Yun Feng, Yue Huang, Li Sun, Yi Jin, Feng-Qing Xu, Fa-Wu Dong, Yan Li, Zhong-Tao Ding, Jun Zhou, Zi-Hua Jiang, Sheng-Tao Yuan, and Jiang-Miao Hu
- Subjects
podophyllotoxin derivatives ,biotin ,anticancer activity ,synthesis ,apoptosis ,Chemistry ,QD1-999 - Abstract
Podophyllotoxin has long been used as an active substance for cytotoxic activity. Fourteen novel biotinylated podophyllotoxin derivatives were designed, synthesized, and evaluated for cytotoxic activity for this study. The synthesized compounds were evaluated for cytotoxic activity in the following human cancer cell lines, SW480, MCF-7, A-549, SMMC-7721, and HL-60 by MTT assay. Most of them exhibited potent cytotoxic effects and compound 15 showed the highest cytotoxic activity among the five cancer cell lines tested, having its IC50 values in the range of 0.13 to 0.84 μM. Apoptosis analysis revealed that compound 15 caused obvious induction of cell apoptosis. Compound 15 significantly down-regulated the expression level of the marker proteins (caspase-3 and PARP) in H1299 and H1975 cells, activated the transcription of IRE1α, increased the expression of GRP78 and XBP-1s, and finally induced apoptosis of H1299 cells. In vivo studies showed that 15 at a dose of 20 mg/kg suppressed tumor growth of S180 cell xenografts in icr mice significantly. Further molecular docking studies suggested that compound 15 could bind well with the ATPase domain of Topoisomerase-II. These data suggest that compound 15 is a promising agent for cancer therapy deserving further research.
- Published
- 2019
- Full Text
- View/download PDF
5. Interaction between Alternaria alternata and monoterpenoids caused by fungal self-protection
- Author
-
Ya-Xian Shi, Rui-Feng Mei, Hao Ding, Si-Ping Deng, Le Cai, Zhong-Tao Ding, and Jun-Li Gan
- Subjects
chemistry.chemical_classification ,biology ,Bioengineering ,Fungus ,biology.organism_classification ,Citral ,Applied Microbiology and Biotechnology ,Biochemistry ,Alternaria alternata ,Hydroxylation ,chemistry.chemical_compound ,Enzyme ,chemistry ,Biotransformation ,Myrcene ,Food science ,Black spot - Abstract
Alternaria alternata is a critical plant pathogen, and the black spot caused by this fungus is the main cause of crop loss. In this study, four monoterpenes commonly found in plant essential oils, β-lonone, citral, γ-terpinene and myrcene, were found to possess a two-way interaction relationship with A. alternata. Four monoterpenes exhibited moderate inhibitory activities against A. alternata with MIC values of 128, 256, 512 and 256 μg/mL, respectively. However, when the concentration of monoterpenes in the culture medium was reduced to 1/4 MIC, A. alternata could facilitate the biotransformation of the aforementioned four monoterpenes by hydroxylation, dihydroxylation or carboxylation. These biotransformations were verified to be promoted by the P450 enzyme. Considering that none of the converted products showed inhibitory activity against A. alternata, these transformations were hypothesized to be self-protective mechanism of A. alternata. Expectedly, the combined use of P450 enzyme inhibitors and monoterpenes exhibited stronger antifungal activities, and could significantly inhibited black spot development in tomatoes. This work provides a reference for the development of effective antifungal agents.
- Published
- 2021
6. Gene Overexpression and RNA Silencing Tools for the Genetic Manipulation of the S-(+)-Abscisic Acid Producing Ascomycete Botrytis cinerea
- Author
-
Zhong-Tao Ding, Zhi Zhang, Di Luo, Jin-Yan Zhou, Juan Zhong, Jie Yang, Liang Xiao, Dan Shu, and Hong Tan
- Subjects
Botrytis cinerea ,gene overexpression ,RNA silencing ,ATMT ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The phytopathogenic ascomycete Botrytis cinerea produces several secondary metabolites that have biotechnical significance and has been particularly used for S-(+)-abscisic acid production at the industrial scale. To manipulate the expression levels of specific secondary metabolite biosynthetic genes of B. cinerea with Agrobacterium tumefaciens-mediated transformation system, two expression vectors (pCBh1 and pCBg1 with different selection markers) and one RNA silencing vector, pCBSilent1, were developed with the In-Fusion assembly method. Both expression vectors were highly effective in constitutively expressing eGFP, and pCBSilent1 effectively silenced the eGFP gene in B. cinerea. Bcaba4, a gene suggested to participate in ABA biosynthesis in B. cinerea, was then targeted for gene overexpression and RNA silencing with these reverse genetic tools. The overexpression of bcaba4 dramatically induced ABA formation in the B. cinerea wild type strain Bc-6, and the gene silencing of bcaba4 significantly reduced ABA-production in an ABA-producing B. cinerea strain.
- Published
- 2015
- Full Text
- View/download PDF
7. Development of an Efficient Electroporation Method for Iturin A-Producing Bacillus subtilis ZK
- Author
-
Zhi Zhang, Zhong-Tao Ding, Dan Shu, Di Luo, and Hong Tan
- Subjects
electroporation ,response surface methodology ,wall-weakening agent ,wild-type B. subtilis ,rapC ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
In order to efficiently introduce DNA into B. subtilis ZK, which produces iturin A at a high level, we optimized seven electroporation conditions and explored an efficient electroporation method. Using the optimal conditions, the electroporation efficiency was improved to 1.03 × 107 transformants/μg of DNA, an approximately 10,000-fold increase in electroporation efficiency. This efficiency is the highest electroporation efficiency for B. subtilis and enables the construction of a directed evolution library or the knockout of a gene in B. subtilis ZK for molecular genetics studies. In the optimization process, the combined effects of three types of wall-weakening agents were evaluated using a response surface methodology (RSM) design, which led to a two orders of magnitude increase in electroporation efficiency. To the best of our limited knowledge, this study provides the first demonstration of using an RSM design for optimization of the electroporation conditions for B. subtilis. To validate the electroporation efficiency, a case study was performed and a gene (rapC) was inactivated in B. subtilis ZK using a suicide plasmid pMUTIN4. Moreover, we found that the rapC mutants exhibited a marked decrease in iturin A production, suggesting that the rapC gene was closely related to the iturin A production.
- Published
- 2015
- Full Text
- View/download PDF
8. Molybdenum nitrides from structures to industrial applications
- Author
-
Hussein A. Miran, Zhong-Tao Jiang, Mohammednoor Altarawneh, and Zainab N. Jaf
- Subjects
Materials science ,Chemical engineering ,chemistry ,Hydrogen ,Molybdenum ,General Chemical Engineering ,chemistry.chemical_element ,Molecule ,Nitride ,Chemical reaction ,Hydrodeoxygenation ,Hydrodesulfurization ,Catalysis - Abstract
Owing to their remarkable characteristics, refractory molybdenum nitride (MoN x )-based compounds have been deployed in a wide range of strategic industrial applications. This review reports the electronic and structural properties that render MoN x materials as potent catalytic surfaces for numerous chemical reactions and surveys the syntheses, procedures, and catalytic applications in pertinent industries such as the petroleum industry. In particular, hydrogenation, hydrodesulfurization, and hydrodeoxygenation are essential processes in the refinement of oil segments and their conversions into commodity fuels and platform chemicals. N-vacant sites over a catalyst’s surface are a significant driver of diverse chemical phenomena. Studies on various reaction routes have emphasized that the transfer of adsorbed hydrogen atoms from the N-vacant sites reduces the activation barriers for bond breaking at key structural linkages. Density functional theory has recently provided an atomic-level understanding of Mo–N systems as active ingredients in hydrotreating processes. These Mo–N systems are potentially extendible to the hydrogenation of more complex molecules, most notably, oxygenated aromatic compounds.
- Published
- 2021
9. Rhodium-Catalyzed Direct Allylation of Simple Arenes by Using Gem-Difluorinated Cyclopropanes as Allyl Surrogates
- Author
-
Zhong Tao Jiang, Yaxin Zeng, and Ying Xia
- Subjects
010405 organic chemistry ,Chemistry ,Organic Chemistry ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Combinatorial chemistry ,0104 chemical sciences ,Catalysis ,Palladium ,Rhodium - Abstract
Gem-difluorinated cyclopropanes have become an important type of allyl surrogate in transition-metal-catalyzed ring-opening processes, as demonstrated recently through various important advances, especially with palladium catalysis. The versatile fluorinated allyl species generated in this way from gem-difluorinated cyclopropanes exhibit unique advantages compared with conventional allyl sources. By using gem-difluorinated cyclopropanes as allyl surrogates, we achieved a direct allylation of simple arenes through rhodium catalysis under mild conditions. This transformation permits directing-group-free allylation of simple arenes, including electron-neutral, electron-rich, and electron-deficient ones. Here, we give a brief introduction to this area and we discuss our thoughts regarding our recent work and its design.1 Introduction2 Our Design3 Condition Optimization and Substrate Scope4 Applications in Synthesis5 Mechanistic Discussions6 Conclusion and Outlook
- Published
- 2021
10. Sequencing and Transcriptional Analysis of the Biosynthesis Gene Cluster of Abscisic Acid-Producing Botrytis cinerea
- Author
-
Tao Gong, Dan Shu, Jie Yang, Zhong-Tao Ding, and Hong Tan
- Subjects
Botrytis cinerea ,abscisic acid ,comparative sequence analysis ,real-time PCR ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Botrytis cinerea is a model species with great importance as a pathogen of plants and has become used for biotechnological production of ABA. The ABA cluster of B. cinerea is composed of an open reading frame without significant similarities (bcaba3), followed by the genes (bcaba1 and bcaba2) encoding P450 monooxygenases and a gene probably coding for a short-chain dehydrogenase/reductase (bcaba4). In B. cinerea ATCC58025, targeted inactivation of the genes in the cluster suggested at least three genes responsible for the hydroxylation at carbon atom C-1' and C-4' or oxidation at C-4' of ABA. Our group has identified an ABA-overproducing strain, B. cinerea TB-3-H8. To differentiate TB-3-H8 from other B. cinerea strains with the functional ABA cluster, the DNA sequence of the 12.11-kb region containing the cluster of B. cinerea TB-3-H8 was determined. Full-length cDNAs were also isolated for bcaba1, bcaba2, bcaba3 and bcaba4 from B. cinerea TB-3-H8. Sequence comparison of the four genes and their flanking regions respectively derived from B. cinerea TB-3-H8, B05.10 and T4 revealed that major variations were located in intergenic sequences. In B. cinerea TB-3-H8, the expression profiles of the four function genes under ABA high-yield conditions were also analyzed by real-time PCR.
- Published
- 2014
- Full Text
- View/download PDF
11. MYOD1 inhibits avian adipocyte differentiation via miRNA-206/KLF4 axis
- Author
-
Qiang-Sen Zhao, Sirui Chen, Sen Wu, Ning Yang, Xiao-Qin Li, Zhuo-Cheng Hou, Zhong-Tao Yin, and Zheng Wang
- Subjects
0301 basic medicine ,Avian ,animal structures ,Veterinary medicine ,Endogeny ,Biology ,Biochemistry ,SF1-1100 ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Adipocyte ,microRNA ,SF600-1100 ,CRISPR/Cas9 ,Activator (genetics) ,Adipocyte differentiation ,Research ,Cell biology ,Animal culture ,030104 developmental biology ,chemistry ,MYOD1 ,Adipogenesis ,KLF4 ,030220 oncology & carcinogenesis ,embryonic structures ,Myoblast Determination Protein 1 ,Lipid biosynthetic process ,Animal Science and Zoology ,miR-206/KLF4 axis ,Food Science ,Biotechnology - Abstract
Background A considerable number of muscle development-related genes were differentially expressed in the early stage of avian adipocyte differentiation. However, the functions of them in adipocyte differentiation remain largely known. In this study, the myoblast determination protein 1 (MYOD1) was selected as a representative of muscle development. We investigated its expression, function, and regulation in avian adipocyte differentiation. Results The expression of MYOD1 decreased significantly in the early stage of avian adipocyte differentiation. CRISPR/Cas9-mediated deletion of MYOD1 induced adipocyte differentiation, whereas over-expression of MYOD1 inhibited adipogenesis. The mRNA-seq data showed that MYOD1 could perturb the lipid biosynthetic process during differentiation. Our results showed that MYOD1 directly up-regulates the miR-206 expression by binding the upstream 1200 bp region of miR-206. Then, over-expression of miR-206 can inhibit the adipogenesis. Furthermore, MYOD1 affected the expression of endogenous miR-206 and its target gene Kruppel-like factor 4 (KLF4), which is an important activator of adipogenesis. Accordingly, the inhibition of miR-206 or over-expression of KLF4 could counteract the inhibitory effect of MYOD1 on adipocyte differentiation. Conclusions Our results establish that MYOD1 inhibits adipocyte differentiation by up-regulating miR-206 to suppress the KLF4 expression. These findings identify a novel function of MYOD1 in adipocyte differentiation, suggesting a potential role in body-fat distribution regulation.
- Published
- 2021
12. Physicochemical properties of geopolymer composites with DFT calculations of in-situ reduction of graphene oxide
- Author
-
Zhong-Tao Jiang, M. Mahbubur Rahman, Monita Olivia, Mohammednoor Altarawneh, Ahmad Ainun Najib, Aman Syam, Amun Amri, Johny Wahyuadi, and Sulistyo Saputro
- Subjects
Materials science ,Scanning electron microscope ,Oxide ,02 engineering and technology ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,law ,0103 physical sciences ,Materials Chemistry ,Composite material ,Fourier transform infrared spectroscopy ,Curing (chemistry) ,010302 applied physics ,Graphene ,Process Chemistry and Technology ,Epoxy ,021001 nanoscience & nanotechnology ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Geopolymer ,Compressive strength ,chemistry ,visual_art ,Ceramics and Composites ,visual_art.visual_art_medium ,0210 nano-technology - Abstract
In this work, the physicochemical properties of palm oil fuel ash (POFA) based geopolymers with the addition of graphene oxide (GO) were investigated. Geopolymer composites were prepared by mixing the treated POFA, sand, NaOH, Na2SiO3, and GO. The mixtures were then cast in mortar molds to form the geopolymer composites, with different GO proportions and curing temperatures applied to the composites. Compressive strength, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses, as well as density functional theory (DFT) calculations, have been performed. The compressive test results showed that the compressive strength increased proportionally with the increase of GO content and decreased when there was an excess of GO. The excessive GO and the limited amount of NaOH activator solution inhibited the formation of reduced graphene oxide (rGO) via an in-situ reduction mechanism. The FTIR and SEM analyses revealed that the excess GO tended to promote the formation of epoxy groups on the GO, which eventually confined the formation of dense agglomeration and led to a decrease in compressive strength. The DFT calculations confirmed the significance of the epoxy group stretching. Overall, the ratio of NaOH to GO is a crucial factor in determining the mechanical properties of geopolymers-GO composites.
- Published
- 2021
13. circGFRA1 affects the sensitivity of triple-negative breast cancer cells to paclitaxel via the miR-361-5p/TLR4 pathway
- Author
-
Gui-Long Guo, Shu-Rong Zheng, Zhi-Hai Zheng, Qi-di Huang, and Zhong-Tao Zhang
- Subjects
Paclitaxel ,Triple Negative Breast Neoplasms ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Breast cancer ,Cell Line, Tumor ,medicine ,Humans ,RNA, Neoplasm ,Molecular Biology ,Luciferase reporter gene ,Triple-negative breast cancer ,030304 developmental biology ,0303 health sciences ,Gene knockdown ,Chemistry ,RNA ,RNA, Circular ,General Medicine ,Tnbc cell ,medicine.disease ,Neoplasm Proteins ,Toll-Like Receptor 4 ,MicroRNAs ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,TLR4 ,Cancer research ,Female ,Signal Transduction - Abstract
In recent years, the role of circular RNAs (circRNAs) in tumours has attracted widespread attention. Some circRNAs have been reported to play a role in triple-negative breast cancer (TNBC). However, circRNAs have rarely been reported in terms of TNBC resistance. This study aimed to clarify that circGFRA1 affects the sensitivity of TNBC cells to paclitaxel (PTX) by the miR-361-5p/TLR4 pathway. Compared with the non-PTX-resistant TNBC cell line MDA-MB-231, the expression of circGFRA1 in the PTX-resistant TNBC cell line MDA-MB-231.PR was significantly increased. The small hairpin RNA-mediated circGFRA1 knockdown inhibited the resistance of TNBC cells to PTX. RNA pull-down assay and luciferase reporter gene assay confirmed the binding between circGFRA1 and miR-361-5p and between miR-361-5p and TLR4. It has been proven that circGFRA1 knockdown can inhibit the resistance of TNBC cells to PTX by promoting the expression of miR-361-5p, and subsequently reduce the expression of TLR4.
- Published
- 2021
14. A simple and efficient copper-catalyzed three-component reaction to synthesize (Z)-1,2-dihydro-2-iminoquinolines
- Author
-
Zhong-Tao Yang, Weiguang Yang, Susu Tao, Xiai Luo, Zhao Yu, and Hui Luo
- Subjects
Sulfonyl ,chemistry.chemical_classification ,chemistry ,Hydrogen bond ,Simple (abstract algebra) ,Component (thermodynamics) ,General Chemical Engineering ,Copper catalyzed ,General Chemistry ,Combinatorial chemistry - Abstract
A operationally simple synthesis of (Z)-1,2-dihydro-2-iminoquinolines that proceeds under mild conditions is achieved by copper-catalyzed reaction of 1-(2-aminophenyl)ethan-1-ones, sulfonyl azides and terminal ynones. In particular, the reaction goes through a base-free CuAAC/ring-opening process to obtain the Z-configured products due to hydrogen bonding.
- Published
- 2021
15. Biotransformation of 1,8-Dihydroxyanthraquinone into Peniphenone under the Fermentation of Aleurodiscus mirabilis
- Author
-
Ya-Xian Shi, Le Cai, Li Zhu, Zhong-Tao Ding, Jun-Li Gan, Sheng-Qi Zhang, Rui-Feng Mei, and Jun-Tao Hu
- Subjects
chemistry.chemical_classification ,Oxidase test ,General Chemical Engineering ,General Chemistry ,Article ,chemistry.chemical_compound ,Metabolic pathway ,Dihydroxyanthraquinone ,Polyketide ,Chemistry ,Enzyme ,Biochemistry ,chemistry ,Biotransformation ,Fermentation ,Emodin ,QD1-999 - Abstract
The present study verified that 1,8-dihydroxyanthraquinone (1), a common component in some industrial raw materials and dyes, could be converted into peniphenone (2), which possesses immunosuppressive activity and other medicinal potential, by Aleurodiscus mirabilis fermentation. The yield of peniphenone (2) after 7 days of fermentation was 11.05 ± 2.19%. To reveal the transformation mechanism, two secondary metabolites, emodin (3) and monodictyphenone (4), were isolated from the fermentation broth of A. mirabilis, implying that polyketide metabolic pathways from emodin (3) to monodictyphenone (4) might exist in A. mirabilis. 1,8-Dihydroxyanthraquinone (1) was suspected to be converted into peniphenone (2) via the same pathway since emodin (3) and 1,8-dihydroxyanthraquinone (1) share very similar skeletons. The P450 enzyme and Baeyer-Villiger oxidase in A. mirabilis were confirmed to catalyze this biotransformation on the basis of ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) analysis. This novel investigation could shed light on the mechanism and therefore development of peniphenone production from 1,8-dihydroxyanthraquinone by microbial fermentation.
- Published
- 2020
16. Paraverrucsins A–F, Antifeedant, and Antiphytopathogenic Polyketides from Rhizospheric Paraphaeosphaeria verruculosa and Induced Bioactivity Enhancement by Coculturing with Host Plant Dendrobium officinale
- Author
-
Zhong-Tao Ding, Ya-Bin Yang, Ming Hu, Cui-Fang Wang, Xue-Qiong Yang, Tong-De Zhao, and Dai-Li Wang
- Subjects
biology ,Chemistry ,Stereochemistry ,General Chemical Engineering ,General Chemistry ,biology.organism_classification ,Article ,Mutarotation ,Minimum inhibitory concentration ,Dendrobium officinale ,Paraphaeosphaeria ,Carcinoma Cell ,Fermentation ,Cytotoxicity ,QD1-999 ,EC50 - Abstract
Six new polyketides named paraverrucsins A–F (1–6) with oxabicyclic and dioxatricyclic skeletons, together with eight known metabolites (7–14), were discovered and isolated from the fermentation medium of Paraphaeosphaeria verruculosa. Paraverrucsin A–C possessed a novel decarboxylated skeleton compared with that of trichocladinols. Their structures were elucidated by extensive spectral analysis and DP4+ calculations. Paraverrucsins B/C and D/E were isolated as a mixture for the mutarotation occurred at C-2. Paraverrucsins B/C, D/E, F/trichocladinol B, 8, and 9 displayed antifeedant activities against silkworm larvae, with antifeedant index percentages ranging from 62.5 to 93.0%, at a concentration of 50 μg/cm2. Among them, Paraverrucsins B/C and 9 had EC50 values at 13.9 and 18.2 μg/cm2. Most compounds showed antifungal activities against phytopathogenic fungi with minimum inhibitory concentration (MIC) values of 16–64 μg/mL. Coculture of P. verruculosa and host plant Dendrobium officinale leads to the enhancement of antifeedant and antiphytopathogenic activities. Compounds 1, 2/3, 4/5, 6/14 were tested for cytotoxicity against five human carcinoma cell lines, HL-60, A549, MCF-7, SW480, and SMMC-7721, while they exhibited selected cytotoxicity against SW480 with inhibition ratios of 32–38% at a concentration of 40 μM.
- Published
- 2020
17. Biotransformation of natural polyacetylene in red ginseng by Chaetomium globosum
- Author
-
Bang Yan Wang, Xue Qiong Yang, Ya-Bin Yang, Zhong Tao Ding, Ya Mei Wu, Li Jiao Shi, Hai Yue Yin, Ming Hu, and Hao Zhou
- Subjects
0301 basic medicine ,Metabolite ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,03 medical and health sciences ,chemistry.chemical_compound ,Ginseng ,0302 clinical medicine ,Biotransformation ,lcsh:Botany ,Active metabolite ,chemistry.chemical_classification ,Chromatography ,Natural product ,Chaetomium globosum ,food and beverages ,NO inhibition ,Polyacetylene ,lcsh:QK1-989 ,030104 developmental biology ,Complementary and alternative medicine ,chemistry ,030220 oncology & carcinogenesis ,Fermentation ,Fermented red ginseng ,Detoxification ,Lactone ,Biotechnology - Abstract
Background Fermentation has been shown to improve the biological properties of plants and herbs. Specifically, fermentation causes decomposition and/or biotransformation of active metabolites into high-value products. Polyacetylenes are a class of polyketides with a pleiotropic profile of bioactivity. Methods Column chromatography was used to isolate compounds, and extensive NMR experiments were used to determine their structures. The transformation of polyacetylene in red ginseng (RG) and the production of cazaldehyde B induced by the extract of RG were identified by TLC and HPLC analyses. Results A new metabolite was isolated from RG fermented by Chaetomium globosum, and this new metabolite can be obtained by the biotransformation of polyacetylene in RG. Panaxytriol was found to exhibit the highest antifungal activity against C. globosum compared with other major ingredients in RG. The fungus C. globosum cultured in RG extract can metabolize panaxytriol to Metabolite A to survive, with no antifungal activity against itself. Metabolites A and B showed obvious inhibition against NO production, with ratios of 42.75 ± 1.60 and 63.95 ± 1.45% at 50 μM, respectively. A higher inhibitory rate on NO production was observed for Metabolite B than for a positive drug. Conclusion Metabolite A is a rare example of natural polyacetylene biotransformation by microbial fermentation. This biotransformation only occurred in fermented RG. The extract of RG also stimulated the production of a new natural product, cazaldehyde B, from C. globosum. The lactone in Metabolite A can decrease the cytotoxicity, which was deemed to be the intrinsic activity of polyacetylene in ginseng.
- Published
- 2020
18. LncRNA KCNQ1OT1 is a key factor in the reversal effect of curcumin on cisplatin resistance in the colorectal cancer cells
- Author
-
He-Yi You, Zhong-Tao Zhang, Yu-Jie Feng, and Zhi-Hai Zheng
- Subjects
0301 basic medicine ,Reporter gene ,Colorectal cancer ,Clinical Biochemistry ,Cell Biology ,General Medicine ,medicine.disease ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,Downregulation and upregulation ,chemistry ,Cell culture ,In vivo ,Apoptosis ,030220 oncology & carcinogenesis ,medicine ,Cancer research ,Curcumin ,Ectopic expression ,Molecular Biology - Abstract
The development of cisplatin resistance is a common cause of cancer recurrence in colorectal cancer (CRC). Though many studies have reported the oncogenic function of long non-coding RNA (LncRNA) KCNQ1OT1 in multiple cancers, few studies explored its role in cisplatin resistance of CRC. Curcumin is a natural phenolic compound extracted from turmeric, which can effectively suppress cisplatin resistance in CRC. This study aims to expound the role of KCNQ1OT1 in cisplatin resistance in CRC cells and whether KCNQ1OT1 participates in the reversal effect of curcumin on cisplatin resistance in CRC. The interplay between KCNQ1OT1 and miR-497 was determined using RNA pull-down assay and dual-luciferase reporter gene assay. The combination of B-cell lymphoma 2 (Bcl-2) and miR-497 was confirmed using dual-luciferase reporter gene assay. Compared with CRC cell line HCT8, the cisplatin-resistant CRC cell line HCT8/DDP exhibited a higher expression level of KCNQ1OT1. Functionally, the silence of KCNQ1OT1 suppressed proliferation and boosted apoptosis in HCT8/DDP cells. Subsequently, we found that KCNQ1OT1 could act as a sponge of miR-497 and remove the suppressive effect of miR-497 on Bcl-2 expression. Curcumin treatment restrained proliferation and facilitated apoptosis in HCT8/DDP cells. While KCNQ1OT1 overexpression removed the effect of curcumin on HCT8/DDP cells via miR-497/ Bcl-2 axis. Finally, the in vivo experiments showed that the inhibitory effect of curcumin on the growth of cisplatin-resistant CRC cells was reserved by the ectopic expression of KCNQ1OT1. In conclusion, KCNQ1OT1 aggravated cisplatin resistance in CRC cells via the miR-497/Bcl-2 axis. Administration of curcumin could effectively downregulate KCNQ1OT1 expression, thus reversing cisplatin resistance in CRC cells.
- Published
- 2020
19. Organocatalytic Regiodivergent Ring Expansion of Cyclobutanones for the Enantioselective Synthesis of Azepino[1,2-a]indoles and Cyclohepta[b]indoles
- Author
-
Wu-Lin Yang, Wei-Ping Deng, Wen Li, and Zhong-Tao Yang
- Subjects
010405 organic chemistry ,Chemistry ,Stereochemistry ,Organic Chemistry ,Michael reaction ,Enantioselective synthesis ,Physical and Theoretical Chemistry ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Sequence (medicine) - Abstract
A regiodivergent organocatalytic enantioselective Michael addition/three-atom ring expansion sequence of electron-withdrawing group activated cyclobutanones with 2-nitrovinylindoles was developed. ...
- Published
- 2020
20. RETRACTED ARTICLE: Two novel nanostructured La(III) coordination polymers were synthesized by sonochemical: crystal structures along with anticancer activity on human nasopharyngeal carcinoma cells
- Author
-
Jian-Ming Tang, Yao-Wei Yuan, Xiao-Hui Wang, Zhong-Tao Cui, Po-Yi Chu, Ye Zhang, and Hong Liu
- Subjects
chemistry.chemical_classification ,medicine.diagnostic_test ,010405 organic chemistry ,Chemistry ,General Chemistry ,Tricarboxylic acid ,Crystal structure ,010402 general chemistry ,medicine.disease ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Nasopharyngeal carcinoma ,Western blot ,Annexin ,Apoptosis ,Cancer cell ,medicine ,Benzoic acid ,Nuclear chemistry - Abstract
The preparation and the structural characterization of two La(III)-based coordination polymers was described in this study, in which {[La(H2O)(BTCTB)]·2H2O}n (1, H3BTCTB = 3,3′,3′′-[1,3,5‐benzenetriyltris(carbonyl amino)] three benzoic acid) and [(La2(TATAB)2)·4DMF·4H2O]n (2, H3TATAB = 4,4,4″s-triazine-1,3,5-triethyl-m-aminobenzoic acid) were prepared by means of two flexible tricarboxylic acid ligands with different joints and functional backbones. Moreover, a sonochemical synthesis way has been carried out to produce the nanostructures of complexes 1 and 2. In addition, their anticancer activity was evaluated on nasopharyngeal carcinoma cells. Firstly, Cell Counting Kit-8 test kit was used to test the cancer cells proliferation after treated with nano 1 or 2. Then, the Annexin V-FITC/PI test was performed and the percentage of the apoptotic cancer cells was determined after nano 1 and 2 treatment. Next, the ROS accumulation after nano 1 and 2 treatment was detected by DCFH-DA detection kit. Finally, the expression level of FHIT in nasopharyngeal carcinoma cells treated with nano 1 and 2 was evaluated via western blot.
- Published
- 2020
21. Role of Additives in Electrochemical Deposition of Ternary Metal Oxide Microspheres for Supercapacitor Applications
- Author
-
Manickam Minakshi Sundaram, Zhong-Tao Jiang, Bankim Chandra Tripathy, Prasanna Kumar Panda, Achyuta Nanda Acharya, Subhashree Mohapatra, Nibedita Swain, and Avijit Biswal
- Subjects
Materials science ,Metal hydroxide ,General Chemical Engineering ,Oxide ,General Chemistry ,Micelle ,Article ,law.invention ,Chemistry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Bromide ,Electrode ,Mixed oxide ,Calcination ,Ternary operation ,QD1-999 - Abstract
A simple two-step approach has been employed to synthesize a cobalt-nickel-copper ternary metal oxide, involving electrochemical precipitation/deposition followed by calcination. The ternary metal hydroxide gets precipitated/deposited from a nitrate bath at the cathode in the catholyte chamber of a two-compartment diaphragm cell at room temperature having a pH ≈ 3. The microstructure of the ternary hydroxides was modified in situ by two different surfactants such as cetyltrimethylammonium bromide and dodecyltrimethylammonium bromide in the bath aiming for enhanced storage performance in the electrochemical devices. The effect of the surfactant produces a transition from microspheres to nanosheets, and the effect of micelle concentration produces nanospheres at a higher ion concentration. The ternary hydroxides were calcined at 300 °C to obtain the desired ternary mixed oxide materials as the electrode for hybrid supercapacitors. X-ray diffraction analysis confirmed the formation of the ternary metal oxide product. The scanning electron microscopy images associated with energy-dispersive analysis suggest the formation of a nanostructured porous composite. Ternary metal oxide in the absence and presence of a surfactant served as the cathode and activated carbon served as the anode for supercapacitor application. DTAB-added metal oxide showed 95.1% capacitance retention after 1000 cycles, achieving 188 F/g at a current density of 0.1 A/g, and thereafter stable until 5000 cycles, inferring that more transition metals in the oxide along with suitable surfactants at an appropriate micellar concentration may be better for redox reactions and achieving higher electrical conductivity and smaller charge transfer resistance. The role of various metal cations and surfactants as additives in the electrolytic bath has been discussed.
- Published
- 2020
22. Mobility of Air-Stable p-type Polythiophene Field-Effect Transistors Fabricated Using Oxidative Chemical Vapor Deposition
- Author
-
Linh Nguyen Thi Truc, Zhong-Tao Jiang, Jae Yong Cho, Kwangsoo No, Han Wook Song, Nik Radevski, Sunghwan Lee, and Tae Hyun Sung
- Subjects
Materials science ,02 engineering and technology ,Chemical vapor deposition ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,law ,0103 physical sciences ,Materials Chemistry ,Electrical and Electronic Engineering ,010302 applied physics ,business.industry ,Contact resistance ,Transistor ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Organic semiconductor ,chemistry ,Polythiophene ,Optoelectronics ,Field-effect transistor ,0210 nano-technology ,business ,Voltage drop ,Voltage - Abstract
Air-stable organic field-effect transistors (FETs) based on an unsubstituted polythiophene (PT) channel, processed using oxidative chemical vapor deposition (oCVD), have been investigated. The intrinsic properties of PT, including its rigid backbone structure and resistance to reactions with water and oxygen, lead to excellent air stability of oCVD PT-based FET devices. The effect of the channel/metalization contact resistance on the field-effect mobility (μFE) of PT-based FETs has also been investigated. Due to the channel/metallization contact resistance, the actual voltages applied to the channel are found to be significantly lower than the intended drain bias because of the voltage drops that occur at the source/drain contacts. Transmission-line measurements reveal that more than 30% of the intended drain bias is lost at all gate voltages applied to the channel. Reconstructed output characteristics excluding the contact effect allow the extraction of a corrected μFE, which is approximately 40% higher than that with contact resistance.
- Published
- 2020
23. Tuning the morphology and redox behaviour by varying the concentration of Fe in a CoNiFe ternary oxide heterostructure for hybrid devices
- Author
-
Achyuta Nanda Acharya, Zhong-Tao Jiang, Manickam Minakshi Sundaram, Prasanna Kumar Panda, Avijit Biswal, Feraih Alenazey, and Bankim Chandra Tripathy
- Subjects
Chemistry ,Oxide ,General Chemistry ,Nanoflower ,Electrochemistry ,Catalysis ,law.invention ,Metal ,chemistry.chemical_compound ,Chemical engineering ,Transition metal ,Transmission electron microscopy ,law ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Calcination ,Ternary operation - Abstract
The effect of the incorporation of a third transition metal cation (Fe–O) and its concentration on the configuration of cobalt nickel oxide has been studied. An attempt has been made to synthesize hierarchical porous cobalt–nickel–iron ternary oxide heterostructure arrays by a simple two-step approach, which is a novel galvanostatic electrochemical technique, followed by calcination. The synthesized ternary oxide heterostructures have been targeted as an electrode for hybrid capacitor application due to their high redox potentials. A diaphragm cell was used for the electrodeposition of the ternary hydroxide at room temperature from a nitrate bath of the corresponding metal ions at a pH of 2. A series of experiments was carried out with a fixed concentration of Co (30 g dm−3) and Ni (30 g dm−3) while varying the concentration of Fe (10, 20 and 30 g dm−3) at the optimized pH of 2. The electrodeposited ternary metal hydroxides were calcined at an optimum temperature of 300 °C for 2 h to obtain the ternary oxide heterostructure. The formation of the ternary oxide heterostructure has been confirmed by X-ray diffraction analysis. The field emission scanning electron microscopy images suggest the formation of a hierarchical nanoflower architecture consisting of an interconnected flower petal with a porous surface and spherical nano crystallites at various Fe concentrations. Transmission electron microscopy supports the formation of nano crystallites with the size of ∼20 nm. Elemental analysis of the ternary oxides was carried out by using atomic absorption spectrophotometry, which suggests that all the materials contain Co, Ni, and Fe in various ratios. The result showed that with an increase in Fe concentration from 10 to 30 g dm−3 with the fixed concentration of Co and Ni, the % iron content in the ternary composite increases with a decrease in the concentration of Co and Ni. The increasing concentration of Fe in the metal oxide decreases the specific capacitance from 440 F g−1 to 272 F g−1, indicating a significant difference in the observed redox processes. However, the cycling stability for both these samples showed an excellent retention of over 92% after 1000 cycles.
- Published
- 2020
24. Identification of disordered metabolic networks in postpartum dairy cows with left displacement of the abomasum through integrated metabolomics and pathway analyses
- Author
-
Sheng Hu He, Fan Hua Wei, Yan Sheng Guo, Li Hua Xu, and Jin Zhong Tao
- Subjects
040301 veterinary sciences ,left displacement of the abomasum ,Cattle Diseases ,Phenylalanine ,postpartum dairy cow ,Mass Spectrometry ,0403 veterinary science ,03 medical and health sciences ,Metabolomics ,Valine ,Internal Medicine ,Animals ,030304 developmental biology ,0303 health sciences ,Full Paper ,General Veterinary ,Chemistry ,Abomasum ,Postpartum Period ,04 agricultural and veterinary sciences ,Metabolism ,metabolomics ,pathway analysis ,Metabolic pathway ,Biochemistry ,Pyrimidine metabolism ,Metabolome ,Ketone bodies ,Cattle ,Female ,Leucine ,liquid chromatography coupled with quadrupole time of flight mass spectrometry ,Biomarkers ,Metabolic Networks and Pathways ,Chromatography, Liquid - Abstract
High-producing dairy cows are easily affected by left displacement of the abomasum (LDA) within 4 weeks postpartum. Although LDA is highly associated with metabolic disturbances, the related information on comprehensive metabolic changes, with the exception of some blood biochemical parameters, remains limited. In this study, the changes in plasma metabolites and in the metabolic profile of postpartum dairy cows with LDA were investigated through liquid chromatography coupled with quadrupole time of flight mass spectrometry (LC-Q/TOF-MS)-based metabolomics, and the metabolic networks related to LDA were constructed through metabolomics pathway analysis (MetPA). An obvious change in the metabolic profile was reflected by significant variations in 68 plasma metabolites in postpartum dairy cows with LDA, and these variations consequently altered 13 metabolic pathways (histidine metabolism, tyrosine metabolism, valine, leucine and isoleucine biosynthesis, phenylalanine, tyrosine and tryptophan biosynthesis, arginine and proline metabolism, tryptophan metabolism, synthesis and degradation of ketone bodies, linoleic acid metabolism, arachidonic acid metabolism, citrate cycle, butanoate metabolism, vitamin B6 metabolism and pyrimidine metabolism). This study shows that the more detailed information obtained by LC-Q/TOF-MS-based metabolomics and MetPA might contribute to a better understanding of the disordered metabolic networks in postpartum dairy cows with LDA.
- Published
- 2020
25. Phomretones A–F, C12 polyketides from the co-cultivation of Phoma sp. YUD17001 and Armillaria sp
- Author
-
Zhong-Tao Ding, Tao Liu, Hao Zhou, Yang Zhi, Hong-Tao Li, Ya-Bin Yang, Fei Xie, and Rui-Ning Yang
- Subjects
biology ,010405 organic chemistry ,Stereochemistry ,Chemistry ,General Chemical Engineering ,Armillaria sp ,Diastereomer ,General Chemistry ,Fungus ,Endophytic fungus ,010402 general chemistry ,biology.organism_classification ,01 natural sciences ,Gastrodia elata ,0104 chemical sciences ,Phoma - Abstract
Six new C12 polyketides, phomretones A–F (1–6), were isolated from the co-culture of Armillaria sp. and the endophytic fungus Phoma sp. YUD17001 associated with Gastrodia elata. Neither fungus produced these compounds when cultured alone. The structures of 1–6 were established on the basis of comprehensive spectroscopic analyses, while their absolute configurations were determined by the comparsion of experimental and calculated ECD spectra. Compounds 2–4 are diastereoisomers of each other and featured high levels of stereoisomerization and oxidation.
- Published
- 2020
26. Biotransformation of α-terpineol by Alternaria alternata
- Author
-
Le Cai, Wei-He Duan, Ya-Xian Shi, Zhong-Tao Ding, Hao Ding, Rui-Feng Mei, and Xiao-Ran Zhang
- Subjects
chemistry.chemical_classification ,0303 health sciences ,biology ,010405 organic chemistry ,Chemistry ,General Chemical Engineering ,Cytochrome P450 ,General Chemistry ,Oxidative phosphorylation ,biology.organism_classification ,01 natural sciences ,Alternaria alternata ,0104 chemical sciences ,Cutworm ,03 medical and health sciences ,chemistry.chemical_compound ,Terpineol ,Enzyme ,Biotransformation ,biology.protein ,Fermentation ,Food science ,030304 developmental biology - Abstract
α-Terpineol (1), the main volatile constituent in some traditional Chinese medicines, has been reported to be metabolized to 4R-oleuropeic acid by the larvae of common cutworms. The present study verified that α-terpineol could be converted to 4R-oleuropeic acid (2) and (1S,2R,4R)-p-menthane-1,2,8-triol (3) by Alternaria alternata fermentation. Using shortened fermentation times, 7-hydroxy-α-terpineol (2a) was identified as an oxidative intermediate, which was consistent with the hypothesis put forward by previous studies. Cytochrome P450 enzymes were also confirmed to catalyze this biotransformation. This is the first study on the biotransformation of α-terpineol by microbial fermentation.
- Published
- 2020
27. Roquefornine A, a sesterterpenoid with a 5/6/5/5/6-fused ring system from the fungus Penicillium roqueforti YJ-14
- Author
-
Zhong-Tao Ding, Hao Ding, Xue-Yun Cai, Dong Gan, Rui Liu, Xiao-Ran Zhang, Yan Shu, Jia-Peng Wang, Cheng-Tong Sun, Rui-Feng Mei, Le Cai, Jun-Tao Hu, and Di-Jiao Zhou
- Subjects
biology ,010405 organic chemistry ,Stereochemistry ,Chemistry ,Organic Chemistry ,Penicillium roqueforti ,Fungus ,010402 general chemistry ,biology.organism_classification ,Ring (chemistry) ,Cytotoxicity ,01 natural sciences ,0104 chemical sciences - Abstract
Roquefornine A, a sesterterpenoid with an unprecedented 5/6/5/5/6-membered pentacyclic system, was characterized from Penicillium roqueforti YJ-14. Its structure was determined by extensive spectroscopic analyses, [Rh2(OCOCF3)4]-induced CD data, and DP4+ calculations. A biosynthetic pathway, cytotoxicity, and anti-inflammatory activity were also discussed.
- Published
- 2020
28. Antifeedant and Antifungal Activities of Metabolites Isolated from the Coculture of Endophytic Fungus Aspergillus tubingensis S1120 with Red Ginseng
- Author
-
Zhong-Tao Ding, Li-Jingfei Sun, Wen-Zhi Shi, Xue-Qiong Yang, Ya-Mei Wu, Ya-Bin Yang, Tong-De Zhao, and Rong-Huan Cen
- Subjects
Antifungal ,Antifungal Agents ,Phoma ,medicine.drug_class ,Phoma herbarum ,Molecular Conformation ,Panax ,Bioengineering ,Microbial Sensitivity Tests ,Selective inhibition ,Plant disease resistance ,Biochemistry ,Endophyte ,Ginseng ,Ascomycota ,medicine ,Animals ,Food science ,Molecular Biology ,Plants, Medicinal ,biology ,Chemistry ,food and beverages ,General Chemistry ,General Medicine ,Endophytic fungus ,Bombyx ,biology.organism_classification ,Aspergillus ,Aspergillus tubingensis ,Insect Repellents ,Molecular Medicine ,Enediynes ,Fatty Alcohols - Abstract
A new globoscinic acid derivative, aspertubin A (1) along with four known compounds, were obtained from the co-culture of Aspergillus tubingensis S1120 with red ginseng. The chemical structures of compounds were characterized by using spectroscopic methods, the calculated and experimental electronic circular dichroism. Panaxytriol (2) from red ginseng, and asperic acid (4) showed significant antifeedant effect with the antifeedant rates of 75 % and 80 % at the concentrations of 50 µg/cm2. Monomeric carviolin (3) and asperazine (5) displayed weak attractant activity on silkworm. All compounds were assayed for antifungal activities against phytopathogens A. tubingensis, Nigrospora oryzae and Phoma herbarum and the results indicated that autotoxic aspertubin A (1) and panaxytriol (2) possessed selective inhibition against A. tubingensis with MIC values at 8 µg/mL. The co-culture extract showed higher antifeedant and antifungal activities against P. herbarum than those of monoculture of A. tubingensis in ordinary medium. So the medicinal plant and endophyte showed synergistic effect on the plant disease resistance by active compounds from the coculture of A. tubingensis S1120 and red ginseng.
- Published
- 2021
29. A New Chlorinated Tetralone from Co-Culture of Insect-Pathogenic Beauveria bassiana and Phytopathogenic Nigrospora oryzae
- Author
-
Zhuo-Xi Zhang, Tong-De Zhao, Xue-Qiong Yang, Hai-Yue Yin, Dai-Li Wang, Ya-Bin Yang, Cui-Fang Wang, and Zhong-Tao Ding
- Subjects
Antifungal ,biology ,010405 organic chemistry ,medicine.drug_class ,media_common.quotation_subject ,Metabolite ,Beauveria bassiana ,Plant Science ,General Chemistry ,Insect ,Bassiana ,biology.organism_classification ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Dendrobium officinale ,chemistry.chemical_compound ,chemistry ,Tetralone ,medicine ,Food science ,Nigrospora oryzae ,media_common - Abstract
In this study, the co-culture of Nigrospora oryzae and Beauveria bassiana, the pathogenic endophytes in the seeds of Dendrobium officinale, were examined for their antagonistic relationship by the production of metabolite. One new chlorotetralone (1) and five known compounds, murranoic acid A (2), 9,12,13-trihydroxy-10-octadecenoic acid (3), 3,3′-methylenebis(4-hydroxy-6-methyl-2H-pyran-2-one) (4), sclerin (5), and (4S)-4,6,8-trihydroxy-3,4-dihydro-1(2H)-naphthalen-1-one (6), were isolated. Compounds 1–5 showed antifungal activity against B. bassiana with MICs of 256, 128, 2, 32, and 64 μg/mL, and N. oryzae with MICs of 64, 256, 256, 256, and 64 μg/mL. Compound 4 showed significant antifungal activity against co-culture of B. bassiana and N. oryzae with MIC at 1 μg/mL.
- Published
- 2021
30. An Insight into Geometries and Catalytic Applications of CeO2 from a DFT Outlook
- Author
-
Mohammednoor Altarawneh, Zhong-Tao Jiang, Zainab N. Jaf, and Hussein A. Miran
- Subjects
Reaction mechanism ,Materials science ,catalytic applications ,Rare earth ,Pharmaceutical Science ,chemistry.chemical_element ,Organic chemistry ,Nanotechnology ,Crystal structure ,Review ,Analytical Chemistry ,Catalysis ,oxygen vacancies ,Metal ,density functional theory (DFT) ,QD241-441 ,Transition metal ,Drug Discovery ,cerium oxide (CeO2) ,Physical and Theoretical Chemistry ,Doping ,Cerium ,chemistry ,Chemistry (miscellaneous) ,visual_art ,visual_art.visual_art_medium ,Molecular Medicine ,surface stability ,fluorite structure - Abstract
Rare earth metal oxides (REMOs) have gained considerable attention in recent years owing to their distinctive properties and potential applications in electronic devices and catalysts. Particularly, cerium dioxide (CeO2), also known as ceria, has emerged as an interesting material in a wide variety of industrial, technological, and medical applications. Ceria can be synthesized with various morphologies, including rods, cubes, wires, tubes, and spheres. This comprehensive review offers valuable perceptions into the crystal structure, fundamental properties, and reaction mechanisms that govern the well-established surface-assisted reactions over ceria. The activity, selectivity, and stability of ceria, either as a stand-alone catalyst or as supports for other metals, are frequently ascribed to its strong interactions with the adsorbates and its facile redox cycle. Doping of ceria with transition metals is a common strategy to modify the characteristics and to fine-tune its reactive properties. DFT-derived chemical mechanisms are surveyed and presented in light of pertinent experimental findings. Finally, the effect of surface termination on catalysis by ceria is also highlighted.
- Published
- 2021
31. Bioactive cytochalasans from the fungus Arthrinium arundinis DJ-13
- Author
-
Bing-Xian Li, Zhong-Tao Ding, Jia-Peng Wang, Yan Shu, Jun-Li Gan, Le Cai, Hao Ding, and Rui Liu
- Subjects
biology ,Chemistry ,Kanamycin ,Plant Science ,General Medicine ,Horticulture ,medicine.disease_cause ,biology.organism_classification ,Biochemistry ,Cytochalasins ,In vitro ,Microbiology ,Nystatin ,Ascomycota ,Candida albicans ,medicine ,Escherichia coli ,Bioassay ,Antibacterial activity ,Cytotoxicity ,Molecular Biology ,medicine.drug - Abstract
The investigation of the metabolites from Arthrinium arundinis DJ-13 grown in solid medium revealed six undescribed cytochalasans, arundisins A-F and twelve known compounds. Their structures were initially investigated in detail by spectroscopic analyses and were further confirmed by X-crystallography and ECD experiments. In the in vitro bioassays, arundisins A and B showed cytotoxic activity against the MCF-7 breast cancer cell line with IC50 values of 18.82 ± 0.36 and 15.20 ± 0.42 μM, respectively. Arundisin F exhibited potent antibacterial activity against Escherichia coli with MIC of 8.00 μg/mL (kanamycin, 2.00 μg/mL), and arundisin D displayed gently antibacterial activity against Candida albicans with MIC of 32.00 μg/mL (Nystatin, 1.00 μg/mL).
- Published
- 2021
32. Sulfasalazine Sensitizes Polyhematoporphyrin-Mediated Photodynamic Therapy in Cholangiocarcinoma by Targeting xCT
- Author
-
Li Xiong, Bo Chen, Zhong-Tao Liu, Zijian Zhang, Heng Zou, Yu Wen, Jiang-Jiao Zhou, Xiongying Miao, Fanhua Kong, and Yan-Wen Zheng
- Subjects
medicine.medical_treatment ,Cell ,Photodynamic therapy ,RM1-950 ,chemistry.chemical_compound ,Sulfasalazine ,Organoid ,medicine ,Pharmacology (medical) ,Viability assay ,Original Research ,Pharmacology ,Chemotherapy ,Chemistry ,fungi ,Glutathione ,polyhematoporphyrin ,medicine.anatomical_structure ,photodynamic therapy ,sulfasalazine ,solute carrier family 7 member 11 ,Cancer research ,Therapeutics. Pharmacology ,cholangiocarcinoma ,Intracellular ,medicine.drug - Abstract
Cholangiocarcinoma (CCA), which is highly malignant, shows a relatively poor prognosis, due to the insensitivity of the tumour to chemotherapy and radiotherapy. Photodynamic therapy (PDT) has become a promising palliative therapeutic option for patients with unresectable cholangiocarcinoma (CCA), while the functional amount of ROS is limited by intracellular redox systemen. Sulfasalazine (SASP), a well-known anti-inflammatory agent, which also acts as an inhibitor of the amino acid transport system xc (xCT), decreases the intracellular glutathione (GSH) level, thus weakening the antioxidant defence of the cell by inhibition of the antiporter. However, the combination of SASP and PDT remains unexplored. We have reported that polyhematoporphyrin (PHP)-mediated PDT inhibits the cell viability of CCA cells and organoids. Furthermore, in PHP-enriched HCCC-9810 and TFK-1CCA cells, SASP enhances the sensitivity to PHP-mediated PDT through a GSH-dependent mechanism. We found that PHP-PDT can up-regulate xCT expression to promote cells against overloaded ROS, while SASP reduces GSH levels. After the combination of SASP and PHP-PDT, cell viability and GSH levels were significantly inhibited. xCT was also observed to be inhibited by SASP in human organoid samples. Our findings suggest that, in combination with PDT, SASP has potential as a promising approach against CCA.
- Published
- 2021
33. The selective anti-fungal metabolites from Irpex lacteus and applications in the chemical interaction of Gastrodia elata, Armillaria sp., and endophytes
- Author
-
Xue-Qiong Yang, Wen-Zhi Shi, Zhong-Tao Ding, Ya-Bin Yang, Dai-Li Wang, and Rong-Huan Cen
- Subjects
Pharmacology ,China ,Gastrodia ,Armillaria ,biology ,Molecular Structure ,Host (biology) ,Metabolite ,Irpex lacteus ,General Medicine ,biology.organism_classification ,Endophyte ,Gastrodia elata ,Fungicides, Industrial ,chemistry.chemical_compound ,Symbiosis ,Glucoside ,chemistry ,Drug Discovery ,Botany ,Seeds ,Endophytes ,Polyporales ,Sesquiterpenes - Abstract
The investigation of the metabolites from endophyte Irpex lacteus cultured in host “tian ma” (Gastrodia elata) revealed five new tremulane sesquiterpenes (1–5), and a new tetrahydrofuran derivative (6). Compound 1 was the first tremulane glucoside, and 6 possessed a rare tetrahydropyran-tetrahydrofuran scaffold. Main metabolite (2,3-dihydroxydodacane-4,7-dione, 14) from I. lacteus showed significant selectivity for antifungal activity against phytopathogen and endophytes associated with G. elata rather than against Armillaria sp. providing nutrition for the host G. elata. 14 accounted for 27.4% of isolated compounds from G. elata medium, and 69.3% by co-culturing with Armillaria sp. So the I. lacteus tended to promote the growth of Armillaria sp. in co-culture by producing 2,3-dihydroxydodacane-4,7-dione (14) to selective inhibit the phytopathogen and endophyte existed in host G. elata for the benefit of G. elata-Armillaria symbiosis. And the results were in accord with the real environment of G. elata depending on the nutrition of Armillaria. Some metabolites had anti-fungal activities against phytopathogens of G. elata with MICs ≤8 μg/mL.
- Published
- 2021
34. A LaFeO 3 supported natural‐clay‐mineral catalyst for efficient pyrolysis of polypropylene plastic material
- Author
-
Gérrard Eddy Jai Poinern, Linh T. Tr. Nguyen, Hanh T.N. Le, Zhong-Tao Jiang, Chien M. Tran, and Tien A. Nguyen
- Subjects
chemistry.chemical_classification ,Materials science ,Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,Coke ,Catalysis ,Thermogravimetry ,Cracking ,Hydrocarbon ,Differential scanning calorimetry ,Catalytic reforming ,Chemical engineering ,chemistry ,Waste Management and Disposal ,Pyrolysis - Abstract
The pyrolysis and catalytic reforming process of waste plastics are the best pathways to handle vast amounts of waste plastics as they can convert these waste polymers into sustainable products. This study aims to incorporate a natural-clay-mineral (NCM) with LaFeO3 nanoparticles, with the LaFeO3/NCM catalyst in the pyrolysis of polypropylene (PP) being used as an example of plastic waste. The decomposition of PP with and without catalyst has been theoretically studied using thermogravimetry (TG) and differential scanning calorimetry (DSC) measurements under atmospheric pressure and nitrogen atmosphere. The TG/DSC results show that (i) the required temperature for pyrolysis of PP with or without catalyst in a practical system ranges from 460°C to 480°C; (ii) the amount of coke produced on the surface of the NCM or LaFeO3 is about 2 wt.% compared with the initial plastic levels; (iii) with the catalyst, PP not only goes through the phase transitions of solid to liquid to gas but also decomposition and combination processes between components from the hydrocarbon chain scission of PP. Gas chromatography–mass spectrometry (GC–MS) results show significant differences in the fuel oil recovered from the pyrolysis and catalytic reforming process. In the presence of the catalyst, cracking components consist of 49.3% alkenes (branched-chain alkenes, cyclo-alkenes, and alkenes) and 34.4% alkanes, while without the catalyst, branched-chain alkenes were up to 90.2%. Repeated pyrolysis and GC–MS investigations demonstrated the reusability of the LaFeO3/NCM catalyst, which is promising for its recycling and the efficient pyrolysis of PP.
- Published
- 2021
35. Mix composition and characterisation of one-part geopolymers with different activators
- Author
-
Richard A. Shuaibu, Zhong Tao, Mahya Askarian, Georgius Adam, and Bijan Samali
- Subjects
Calcium hydroxide ,Materials science ,Sodium oxide ,0211 other engineering and technologies ,020101 civil engineering ,Sodium silicate ,02 engineering and technology ,Building and Construction ,Lithium hydroxide ,0201 civil engineering ,Geopolymer ,Potassium carbonate ,chemistry.chemical_compound ,Compressive strength ,chemistry ,Chemical engineering ,Fly ash ,021105 building & construction ,General Materials Science ,Civil and Structural Engineering - Abstract
To improve the commercial viability of geopolymers, there is a need to develop one-part geopolymer mixes. In this research, 100% fly ash or a mixture of fly ash and slag was employed as the precursor. Meanwhile, the highly corrosive alkali solutions used as activators in conventional geopolymers were replaced by different solid activators (in powder form), such as sodium silicate, calcium hydroxide, sodium oxide, lithium hydroxide, potassium carbonate or their combinations. The mixes were subjected to both ambient and heat curing to check the influence of curing conditions. Effects of type/combination of the solid activators on the workability, early and final strength, hardened density and microstructure of these one-part geopolymer mixes were examined. The incorporation of slag in the binder increased the early and final strength of mixes but reduced the workability. Furthermore, the type/combination of solid alkaline activators affects the microstructure of the geopolymer gels and subsequently impacts the mechanical properties. Among the investigated ambient cured geopolymers, a relatively high compressive strength of 38 MPa at 28 days was obtained when the geopolymer precursor was composed of 50 wt% fly ash and 50 wt% slag activated by a combination of sodium silicate, calcium hydroxide and lithium hydroxide.
- Published
- 2019
36. Induction of Antiphytopathogenic Metabolite and Squalene Production and Phytotoxin Elimination by Adjustment of the Mode of Fermentation in Cocultures of Phytopathogenic Nigrospora oryzae and Irpex lacteus
- Author
-
Yu-Jie Luo, Ya-Bin Yang, Jing-Jing Qian, Zhong-Tao Ding, Shi-Xi Liu, Ya-Mei Wu, Xue-Qiong Yang, and Qing-Yan Zhou
- Subjects
0106 biological sciences ,biology ,medicine.drug_class ,Metabolite ,010401 analytical chemistry ,Antibiotics ,Irpex lacteus ,food and beverages ,General Chemistry ,Phytotoxin ,biology.organism_classification ,01 natural sciences ,Endophyte ,0104 chemical sciences ,Microbiology ,Squalene ,chemistry.chemical_compound ,chemistry ,In vivo ,medicine ,Fermentation ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
The investigation of the metabolites from different cocultures of Nigrospora oryzae and Irpex lacteus in solid medium revealed two new squalenes (1 and 2); one new azaphilone (3); two new tremulane sesquiterpenes (4 and 5); and three known compounds, conocenol B (6), conocenol C (7), and 4-(4-dihydroxymethylphenoxy)benzaldehyde (8). The antagonistic relationship was examined by studying metabolite production. The production of compounds 6 and 8 by I. lacteus after the induction of coculture indicated significant selectivity for antifungal activity against phytopathogenic N. oryzae, with MICs of 16 μg/mL; compounds 6 and 8 also exhibited antifungal activities in vivo against Cerasus cerasoides infected by N. oryzae at concentrations of 100 μg/mL. New compounds 2 and 4 showed antifungal activities against Colletotrichum gloeosporioides, with MICs of 8 μg/mL, and compound 4 showed antifungal activity against Didymella glomerata with an MIC of 1 μg/mL. These results indicate that the mutually antagonistic relationship in the coculture of the phytopathogen and the endophyte can result in antibiotics that inhibit the phytopathogen and downregulate the production of phytotoxins by phytopathogenic N. oryzae. New compound 5 from I. lacteus showed weak activity against acetylcholinesterase (AChE), with an inhibition ratio of 16% at a concentration of 50 μM.
- Published
- 2019
37. Glucoside Derivatives Of Podophyllotoxin: Synthesis, Physicochemical Properties, And Cytotoxicity
- Author
-
Jun Zhou, Zi-Hua Jiang, Zhong-Tao Ding, Hong-Mei Li, Xing-Zhi Yang, Liu Yang, Cheng-Ting Zi, Jiang-Miao Hu, and Qing-Hua Kong
- Subjects
0301 basic medicine ,Pharmacology ,chemistry.chemical_classification ,Pharmaceutical Science ,Glycoside ,In vitro ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,Podophyllotoxin ,Biochemistry ,Glucoside ,chemistry ,Cell culture ,030220 oncology & carcinogenesis ,Drug Discovery ,medicine ,Cytotoxic T cell ,Cytotoxicity ,Etoposide ,medicine.drug - Abstract
Background Widespread concern of the side effects and the broad-spectrum anticancer property of podophyllotoxin as an antitumor agent highlight the need for the development of new podophyllotoxin derivatives. Although some per-butyrylated glucosides of podophyllotoxin and 4β-triazolyl-podophyllotoxin glycosides show good anticancer activity, the per-acetylated/free of podophyllotoxin glucosides and their per-acetylated are not well studied. Methods A few glucoside derivatives of PPT were synthesized and evaluated for their in vitro cytotoxic activities against five human cancer cell lines, HL-60 (leukemia), SMMC-7721 (hepatoma), A-549 (lung cancer), MCF-7 (breast cancer), and SW480 (colon cancer), as well as the normal human pulmonary epithelial cell line (BEAS-2B). In addition, we investigated the structure-activity relationship and the physicochemical property-anticancer activity relationship of these compounds. Results Compound 6b shows the highest cytotoxic potency against all five cancer cell lines tested, with IC50 values ranging from 3.27±0.21 to 11.37±0.52 μM. We have also found that 6b displays higher selectivity than the etoposide except in the case of HL-60 cell line. The active compounds possess similar physicochemical properties: MSA > 900, %PSA 2, MW > 700 Da, and RB > 10. Conclusion We synthesized several glucoside derivatives of PPT and tested their cytotoxicity. Among them, compound 6b showed the highest cytotoxicity. Further studies including selectivity of active compounds have shown that the selectivity indexes of 6b are much greater than the etoposide except in the case of HL-60 cell line. The active compounds possessed similar physicochemical properties. This study indicates that active glucoside analogs of podophyllotoxin have potential as lead compounds for developing novel anticancer agents.
- Published
- 2019
38. Application of the Ethyl Acetate Extract of Cichorium as a Potential Photosensitizer in Photodynamic Therapy Induces Apoptosis and Autophagy in Colorectal Cancer Cell Lines via the Protein Kinase R-Like Endoplasmic Reticulum Kinase Pathway
- Author
-
Kai Liu, Li Xiong, Zhong-Tao Liu, Zhen-Xing Zou, Zheng-Chun Wu, Yu Wen, Jiang-Jiao Zhou, Heng Zou, Zi-Jian Zhang, Yun-Peng Huang, Wei Chen, Kun-Peng Wang, and Shi-Lin Luo
- Subjects
chemistry.chemical_classification ,Reactive oxygen species ,medicine.medical_treatment ,0206 medical engineering ,Biomedical Engineering ,Pharmaceutical Science ,Medicine (miscellaneous) ,Bioengineering ,Photodynamic therapy ,02 engineering and technology ,Glutathione ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,Molecular biology ,chemistry.chemical_compound ,chemistry ,Annexin ,Apoptosis ,medicine ,Glutathione disulfide ,General Materials Science ,Photosensitizer ,0210 nano-technology ,Cytotoxicity - Abstract
The present study aims to evaluate the effect of the ethyl acetate extract of Cichorium (EAEC) as a novel photosensitizer in photodynamic therapy (PDT) of colorectal carcinoma (CRC) HCT116 and SW620 cells. The absorption and fluorescence spectra of EAEC were measured using a UV-vis spectrophotometer and fluorescence spectrophotometer, respectively. EAEC-induced reactive oxygen species (ROS) production in HCT116 and SW620 cells was detected using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and glutathione/glutathione disulfide (GSH/GSSG). The photo- and dark toxicities of EAEC were estimated using the Cell Counting Kit-8 (CCK-8) assay. Cellular uptake and localization of EAEC were detected by confocal laser fluorescence microscopy. Annexin V-FITC/PI staining, Western blotting and immunofluorescence staining were used to assess apoptosis and autophagy. The antitumor activity of EAEC was confirmed in a xenograft model. Finally, effects on the PERK pathway were verified using qRT-PCR and Western blotting. EAEC displayed absorption and fluorescence emission peaks at 660 nm and 678 nm, respectively. EAEC induced ROS production in CRC cells. Assessment of dark toxicity showed that treatment with EAEC alone induced little cytotoxicity in CRC or normal cells but that EAEC-PDT induced significant photocytotoxicity in CRC cells in a time- and dose-dependent manner. After cellular uptake, EAEC was located in the mitochondria. Treatment with EAEC-PDT reduced xenograft tumor size. Further evaluation suggested that activation of the PERK pathway mediates these effects, as the apoptotic rate and autophagy flux increased markedly after EAEC-PDT. EAEC, a natural photosensitizer extracted from Cichorium, displays potential utility in PDT of CRC by targeting the PERK pathway.
- Published
- 2019
39. Effect of Cross‐Linked Hyaluronate Scaffold on Cartilage Repair: An In Vivo Study
- Author
-
Qian-Qian Chen, Jian-Ying Chen, Shi-Peng Xiao, Zhong-Tao Li, Shenghou Liu, Tang Liansheng, Guang-Hui Cheng, and Wen-guang Liu
- Subjects
Cartilage, Articular ,Scientific Articles ,medicine.medical_specialty ,Scaffold ,Histology ,Swine ,Sodium hyaluronate ,Type II collagen ,Urology ,Matrix (biology) ,Glycosaminoglycan ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cartilage repair ,Tissue engineering ,lcsh:Orthopedic surgery ,In vivo ,medicine ,Animals ,Scientific Article ,Orthopedics and Sports Medicine ,Femur ,Hyaluronic Acid ,Collagen Type II ,Biomechanical ,Glycosaminoglycans ,030222 orthopedics ,Tissue Scaffolds ,business.industry ,Cartilage ,Disease Models, Animal ,lcsh:RD701-811 ,medicine.anatomical_structure ,chemistry ,Swine, Miniature ,Surgery ,Cross‐linked hyaluronate scaffold ,business ,030217 neurology & neurosurgery - Abstract
Objective To determine the safety and effectiveness of a cross-linked sodium hyaluronate (CHA) scaffold in cartilage repair. Methods Physicochemical properties of the scaffold were determined. The safety and effectiveness of the scaffold for cartilage repair were evaluated in a minipig model of a full-thickness cartilage defect with microfracture surgery. Postoperative observation and hematological examination were used to evaluate the safety of the CHA scaffold implantation. Pathological examination as well as biomechanical testing, including Young's modulus, stress relaxation time, and creep time, were conducted at 6 and 12 months postsurgery to assess the effectiveness of the scaffold for cartilage repair. Furthermore, type II collagen and glycosaminoglycan content were determined to confirm the influence of the scaffold in the damaged cartilage tissue. Results The results showed that the routine hematological indexes of the experimental animals were within the normal physiological ranges, which confirmed the safety of CHA scaffold implantation. Based on macroscopic observation, it was evident that repair of the defective cartilage in the animal knee joint began during the 6 months postoperation and was gradually enhanced from the central to the surrounding region. The repair smoothness and color of the 12-month cartilage samples from the operation area were better than those of the 6-month samples, and the results for the CHA scaffold implantation group were better than the control group. Greater cell degeneration and degeneration of the adjacent cartilage was found in the implantation group compared with the control group at both 6 and 12 months postoperation, evaluated by O'Driscoll Articular Cartilage Histology Scoring. Implantation with the CHA scaffold matrix promoted cartilage repair and improved its compression capacity. The type II collagen level in the CHA scaffold implantation group tended to be higher than that in the control group at 6 months (2.33 ± 1.50 vs 1.68 ± 0.56) and 12 months postsurgery (3.37 ± 1.70 vs 2.06 ± 0.63). The GAG content in the cartilage of the control group was significantly lower than that of the experimental group (2.17 ± 0.43 vs 3.64 ± 1.17, P = 0.002 at 6 months and 2.27 ± 0.38 vs 4.12 ± 1.02, P = 0.002 at 12 months). Type II collagen and glycosaminoglycan content also demonstrated that CHA was beneficial for the accumulation of both these vital substances in the cartilage tissue. Conclusions The CHA scaffold displayed the ability to promote cartilage repair when applied in microfracture surgery, which makes it a promising material for application in the area of cartilage tissue engineering.
- Published
- 2019
40. Hydrostatic bath synthesis of conductive polypyrrole/reduced graphene oxide aerogel as compression sensor
- Author
-
Chuan Yi Foo, Mohammednoor Altarawneh, Hong Ngee Lim, Nay Ming Huang, and Zhong-Tao Jiang
- Subjects
Materials science ,Polymers and Plastics ,Graphene ,Organic Chemistry ,Oxide ,General Physics and Astronomy ,Aerogel ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Polypyrrole ,01 natural sciences ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,Adsorption ,X-ray photoelectron spectroscopy ,chemistry ,Chemical engineering ,Polymerization ,Electrical resistance and conductance ,law ,Materials Chemistry ,0210 nano-technology - Abstract
A conductive and elastic polypyrrole/reduced graphene oxide aerogel (PGA) was synthesized through a hydrostatic bath method followed by freeze-drying. Through this method, the self-agglomeration and oxidative polymerization of rGO and polypyrrole occurred synergistically in a controlled environment, which resulted in a 3D conductive aerogel matrix. The optical spectroscopy, including FT-IR and XPS, showed the distinguished vibration band of polypyrrole and π-π interaction, which evidenced the successful polymerization of the pyrrole monomer through the synergistic assembly process. The presence of flexible rGO nanosheets as an aerogel backbone provided a strong mechanical support and deposition sites for polypyrrole nanoparticles, which contributed to the overall elasticity. Furthermore, the polypyrrole nanoparticles not only addressed the stacking issue of rGO but further enhanced the reactive surface area by eight times of magnitude compared to pure graphene aerogel (GA) produced by the same technique. Molecular modeling estimates adsorption energies for the polypyrrole molecule over the rGO surface and further predict the dominant functional group that involve in the formation of PGA. The as-synthesized PGA provide a significant electrical resistance changes (>80%) before and after compression, which responded exceptionally well upon compression by lighting up LEDs that were arranged in parallel in an electrical circuit.
- Published
- 2019
41. Surface structural features and optical analysis of nanostructured Cu-oxide thin film coatings coated via the sol-gel dip coating method
- Author
-
Abul Hossain, M. Mahbubur Rahman, I. wantono, Neni Frimayanti, Hatem Taha, Syamsu Herman, Ella Awaltanova, Andrizal, Amun Amri, Humayun Kabir, Zhong-Tao Jiang, Kamrul Hasan, Khalil Ibrahim, Syaiful Bahri, and Chun-Yang Yin
- Subjects
Copper oxide ,Materials science ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,01 natural sciences ,Dip-coating ,chemistry.chemical_compound ,Coating ,X-ray photoelectron spectroscopy ,0103 physical sciences ,Materials Chemistry ,Thin film ,010302 applied physics ,Process Chemistry and Technology ,021001 nanoscience & nanotechnology ,Copper ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Chemical engineering ,Tauc plot ,Ceramics and Composites ,engineering ,0210 nano-technology - Abstract
Nanostructured thin film coatings of copper oxide (Cu-oxide) were investigated to determine their physical structure, surface morphology, surface electronic bonding states, and optical properties. The Cu-oxide had been coated onto reflective aluminum substrates via a facile one-step sol–gel dip-coating route using a copper nitrate precursor. Characterizations were conducted using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), and ultra-violet visible (UV–Vis) spectroscopic methods, and representative sol-gel reactions using copper nitrate precursor were proposed. The XPS spectra confirmed the presence of copper oxide elements. Further exploration of the Cu2p3/2 peak in XPS spectra revealed that the electronic structure of the copper component consisted of tetrahedral Cu(I) and octahedral Cu(II) with the presence of octahedral Cu(II) enabling coatings to have high absorption levels across the solar spectrum. The deconvolution of the O1s spectra exhibited three curve-fitting components: the lattice O2−, surface oxygen, and subsurface O− species. FESEM results showed that the coating surface was an agglomerated copper oxide nanoparticles structure forming a porous structure. The optical band-gap of Cu-oxide thin film coatings, via the Tauc plot, was 2.7 eV.
- Published
- 2019
42. Catalytic de-chlorination of products from PVC degradation by magnetite (Fe3O4)
- Author
-
O.H. Ahmed, Mohammednoor Altarawneh, Bogdan Z. Dlugogorski, Zhong-Tao Jiang, and Mohammad Al-Harahsheh
- Subjects
Inorganic chemistry ,Iron oxide ,General Physics and Astronomy ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Chloride ,Catalysis ,Metal ,chemistry.chemical_compound ,symbols.namesake ,Transition metal ,medicine ,Magnetite ,Arrhenius equation ,Surfaces and Interfaces ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Surfaces, Coatings and Films ,chemistry ,visual_art ,Halogen ,visual_art.visual_art_medium ,symbols ,0210 nano-technology ,medicine.drug - Abstract
This contribution provides a systematic theoretical thermo-kinetic study of the initial reactions between Fe3O4(111) surface, as a representative model for metal oxides in electric arc furnace dust (EAFD) with HCl and selected chlorinated hydrocarbons, as major products from thermal degradation of PVC. Formation of the experimentally observed iron chloride occurs by subsequent dissociative addition of HCl molecules followed by H migration into a surface hydroxyl group. We provided Arrhenius parameters for reactions dictating the conversion of iron oxide into its chloride. In the course of the interaction of chlorinated alkanes and alkenes with the Fe3O4 surface, the opening channel in the dissociative addition route requires lower activation barriers in reference to the direct HCl elimination pathways. However, sizable activation barriers are encountered in the subsequent β C H bond elimination step. Estimated electronic charges confirm the nature of surface Fe Cl bonds as Lewis acid−base pair. The obtained accessible reaction barriers for reactions of chlorinated alkanes and alkenes with the title iron oxide demonstrate that the latter serve as active catalysts in producing clean olefins streams from chlorinated alkanes. Results from this study should be instrumental to understand, on a precise atomic scale, mechanisms operating in fixation of halogens on transitional metal oxides; a viable thermal recycling approach for polymeric materials laden with halogenated constituents.
- Published
- 2019
43. Inducing secondary metabolite production from Daldinia eschscholzii JC-15 by red ginseng medium
- Author
-
Bang-Yan Wang, Chen-Hao Zhu, Xue-Qiong Yang, Xue-Yin Wang, Zhong-Tao Ding, Shuang Yang, Ya-Bin Yang, Ting-Ting Xu, Ning-Hua Tan, and Hao Zhou
- Subjects
010405 organic chemistry ,Daldinia eschscholzii ,Metabolite ,Organic Chemistry ,Dietary supplement ,food and beverages ,Plant Science ,Secondary metabolite ,complex mixtures ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Analytical Chemistry ,010404 medicinal & biomolecular chemistry ,Ingredient ,chemistry.chemical_compound ,Ginseng ,chemistry ,medicine ,Food science ,Microbial metabolite ,medicine.drug - Abstract
Red ginseng (RG) is one of the most popular herbal medicines and used as a dietary supplement in recent years. The bioactive ingredient in RG can induce the production of novel microbial metabolite from fermented RG. Using the one strain-many compounds strategy, the reinvestigation of the metabolites from Daldinia eschscholzii JC-15 cultured in red ginseng medium led to the isolation of an unprecedented benzopyran-naphthalene hybrid, daldinsin (1) and a new lactone (2). In this research, a new lactone, 8-hydroxylhelicascolide A (2) instead of helicascolide A was produced by the D. eschscholzii JC-15 induced by the red ginseng medium. Compound 1 showed anti-acetylcholinesterase activity with the inhibition ratio of 38.8% at 50 μM. Compound 2 indicated antimicrobial activities against Fusarium Solani, F. oxysporum, and Escherichia coli with MICs at 128 μg/mL. RG is therefore a promising activator in production of novel microbial metabolite.
- Published
- 2019
44. (-)-Grandiflorimine, a new dibenzopyrrocoline alkaloid with cholinesterase inhibitory activity from Illigera grandiflora
- Author
-
Xue-Yun Cai, Dong Gan, Zhong-Tao Ding, Le Cai, Di-Jiao Zhou, Xue-Jiao Li, and Jian-Wei Dong
- Subjects
Circular dichroism ,biology ,010405 organic chemistry ,Stereochemistry ,Alkaloid ,Organic Chemistry ,Plant Science ,Inhibitory postsynaptic potential ,01 natural sciences ,Biochemistry ,Acetylcholinesterase ,0104 chemical sciences ,Analytical Chemistry ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,chemistry ,biology.protein ,Boldine ,Two-dimensional nuclear magnetic resonance spectroscopy ,Butyrylcholinesterase ,Cholinesterase - Abstract
A new dibenzopyrrocoline alkaloid, (-)-grandifloramine (1), together with five known ones, actinodaphnine (2), N-methyllaurotetanine (3), boldine (4), lindcarpine (5), and (+)-norboldine (6), were isolated from Illigera grandiflora W. W. Sm. et J. F. Jeff. The structure of 1 was identified by HRESIMS, 1D/2D NMR, and electronic circular dichroism (ECD) spectra. Compound 1 and 2 exhibited the moderate inhibitory activity against acetylcholinesterase and 3 showed moderate butyrylcholinesterase inhibitory activity. This is the first report of the chemical constituents of I. grandiflora.
- Published
- 2019
45. Studies of annealing impact on the morphological, opto-dielectric and mechanical behaviors of molybdenum-doped CrN coatings
- Author
-
Zhong-Tao Jiang, Xiaoli Zhao, Abul Hossain, T. S. Y. Moh, Amun Amri, Raba’ah Syahidah Azis, Zhifeng Zhou, Hatem Taha, Khalil Ibrahim, Humayun Kabir, Bouraire Ahmed, Mohammednoor Altarawneh, and M. Mahbubur Rahman
- Subjects
010302 applied physics ,Materials science ,Annealing (metallurgy) ,Metals and Alloys ,chemistry.chemical_element ,02 engineering and technology ,Surfaces and Interfaces ,Nanoindentation ,Sputter deposition ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Crystallinity ,Lattice constant ,chemistry ,Molybdenum ,0103 physical sciences ,Materials Chemistry ,Composite material ,0210 nano-technology ,Chromium nitride ,Elastic modulus - Abstract
In the present study, molybdenum doped chromium nitride coatings deposited onto silicon substrates via unbalanced magnetron sputtering, in as-deposited and annealed conditions, at 500–800 °C in steps of 100 °C, were studied to reveal their temperature dependent structural, morphological, optical and mechanical behaviors. An analysis of these features was carried out using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet visible (UV–Vis) spectroscopy, nanoindentation and finite element modeling (FEM) techniques. XRD results exhibited a significant improvement in the crystallinity of the Molybdenum (Mo)-doped chromium nitride (CrN) coatings along (111) and (200) diffraction planes, as the annealing temperatures increased. The lattice parameters gradually decreased from 4.20 to 4.12 A as the temperature increased. The same tendency was also observed for lattice microstrains and residual stresses. Smooth grain-like surfaces were observed by FESEM imaging techniques. At an annealing temperature of 700 °C, the spectral absorptance of Mo:CrN films attained its peak value (86%), whereas the energy band-gaps were reduced from 2.48 to 1.14 eV. The other optical parameters such as complex dielectric constants, Urbach energy values, and steepness parameters of these coatings were also discussed. The hardness and elastic modulus of the as-deposited Mo:CrN films were estimated to be 18.4 and 287 GPa, respectively. At a film thickness of 1.0 μm, the highest stress of 20 GPa was evaluated, via FEM studies, at the interface between the film and the substrate. As the film thickness was enhanced, the stress level decreased. At higher annealing temperatures, both the mechanical hardness (H) and the elastic modulus (E) of Mo-doped CrN coatings dwindled.
- Published
- 2019
46. High temperature in-situ phase stability of sputtered TiAlxN coatings
- Author
-
Ehsan Mohammadpour, Xiaoli Zhao, Willey Yun Hsien Liew, Zhong-Tao Jiang, Zhifeng Zhou, T. S. Y. Moh, Jean-Pierre Veder, Shyam Bharatkumar Patel, Sunghwan Lee, and Nicholas Mondinos
- Subjects
Materials science ,Mechanical Engineering ,Metals and Alloys ,chemistry.chemical_element ,02 engineering and technology ,Nanoindentation ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Grain size ,0104 chemical sciences ,Lattice constant ,chemistry ,X-ray photoelectron spectroscopy ,Mechanics of Materials ,Aluminium ,Materials Chemistry ,Surface roughness ,Composite material ,Thin film ,0210 nano-technology ,Tin - Abstract
The temperature dependence of phase composition and lattice parameters, for TiAlxN thin film coating, are experimentally investigated by in-situ synchrotron radiation X-ray diffraction (SR-XRD), at temperatures between 25 °C and 700 °C. Mechanical properties, such as: Young's modulus (E), hardness (H) and plastic deformation index (PDI) – were experimentally determined by nanoindentation, at 25 °C. Crystalline structural analysis, of SR-XRD results, indicates the major phases are TiN and AlN; with Ti2O and TiO2 phases also present above 600 °C. The lattice constants increased with an increase in temperature. Atomic and phase compositions, at 25 °C, were also verified by X-ray photoelectron spectroscopy (XPS). Field emission scanning electron microscopy (FESEM) images display an increase in surface roughness and reduction in grain size, with increasing Aluminium percentage (Al%). Nanoindentation analysis showed a maximum hardness of 25.1 ± 1.5 GPa (sample containing 12% Al), which was subsequently reduced upon addition of more Aluminium. Finite element modelling (FEM), including von Mises stress distribution, indicates lower mechanical integrity, for samples with high Al% content.
- Published
- 2019
47. Vertical sleeve gastrectomy improves liver and hypothalamic functions in obese mice
- Author
-
Zhong-Tao Zhang, Peixin Li, Zhijian Rao, Brenton Thomas Laing, Taylor Landry, Wyatt Bunner, Amber Prete, Hu Huang, and Yuan Yuan
- Subjects
medicine.medical_specialty ,education.field_of_study ,Tyrosine hydroxylase ,Glycogen ,Endocrinology, Diabetes and Metabolism ,Population ,Biology ,medicine.disease ,chemistry.chemical_compound ,Endocrinology ,medicine.anatomical_structure ,Insulin resistance ,chemistry ,Hypothalamus ,Internal medicine ,Diabetes mellitus ,parasitic diseases ,Gene expression ,medicine ,Neuron ,education - Abstract
Vertical sleeve gastrectomy (VSG) is an effective surgery to treat obesity and diabetes. However, the direct effect of VSG on metabolic functions is not fully understood. We aimed to investigate if alterations in hypothalamic neurons were linked with perturbations in liver metabolism after VSG in an energy intake-controlled obese mouse model. C57BL/6 and hrNPY-GFP reporter mice received HFD for 12 weeks and were then divided into three groups: Sham (ad lib), Sham (pair-fed) with VSG and VSG. Food intake was measured daily, and blood glucose levels were measured before and after the study. Energy expenditure and body composition were determined. Serum parameters, liver lipid and glycogen contents were measured and gene/protein expression were analyzed. Hypothalamic POMC, AgRP/NPY and tyrosine hydroxylase-expressing neurons were counted. The following results were obtained. VSG reduced body weight gain and adiposity induced by HFD, increased energy expenditure independent of energy intake. Fed and fasted blood glucose levels were reduced in the VSG group. While serum active GLP-1 level was increased, the active ghrelin and triglycerides levels were decreased along with improved insulin resistance in VSG group. Liver lipid accumulation, glycogen content and gluconeogenic gene expression were reduced in the VSG group. In the hypothalamus, TH-expressing neuron population was decreased, and the POMC-expressing neuron population was increased in the VSG group. In conclusion, our data suggest that VSG improves metabolic symptoms by increasing energy expenditure and lowering lipid and glycogen contents in the liver. These physiological alterations are possibly related to changes in hypothalamic neuron populations.
- Published
- 2019
48. A mechanical and modelling study of magnetron sputtered cerium-titanium oxide film coatings on Si (100)
- Author
-
Shyam Bharatkumar Patel, Zhong-Tao Jiang, Jean-Pierre Veder, Xiaoli Zhao, Zhifeng Zhou, Nicholas Mondinos, Nik Radevski, and Kevin S. Jack
- Subjects
010302 applied physics ,Cerium oxide ,Materials science ,Process Chemistry and Technology ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,Nanoindentation ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Titanium oxide ,Contact angle ,chemistry.chemical_compound ,Cerium ,chemistry ,Rutile ,0103 physical sciences ,Materials Chemistry ,Ceramics and Composites ,Composite material ,Thin film ,0210 nano-technology - Abstract
Ce/Ti mixed metal oxide thin films have well known optoelectrical properties amongst several other physio-chemical properties. Changes in the structural and mechanical properties of magnetron sputtered Ce/Ti oxide thin films on Si (100) wafers with different Ce:Ti ratios are investigated experimentally and by modelling. X-ray Photoemission Spectroscopy (XPS) and X-ray diffraction (XRD) confirm the primary phases as trigonal Ce2O3 and rutile form of TiO2 with SiO2 present in all prepared materials. FESEM imaging delivers information based on the variation of grain size, the mixed Ce/Ti oxides providing much smaller grain sizes in the thin film/substrate composite. Nanoindentation analysis concludes that the pure cerium oxide film has the highest hardness value (20.1 GPa), while the addition of excess titanium oxide decreases the hardness of the film coatings. High temperature in-situ XRD (up to 1000 degrees C) results indicate high thermal phase stability for all materials studied. The film with Ce:Ti = 68%:32% has a new additional minor oxide phase above 800 degrees C. Contact angle experiments suggest that the chemical composition of the surface is insignificant affecting the water contact angle. Results show a narrow band of 87.7-95.7 degrees contact angle. The finite element modelling (FEM) modelling of Ce/Ti thin film coatings based on Si(100); Si(110); silica and steel substrates shows a variation in stress concentration.
- Published
- 2019
49. Inducing Secondary Metabolite Production by Co-culture of the Endophytic Fungus Phoma sp. and the Symbiotic Fungus Armillaria sp
- Author
-
Hong-Tao Li, Zhong-Tao Ding, Rong-Ting Duan, Ya-Bin Yang, Hao Zhou, Lin-Huan Tang, Xue-Qiong Yang, and Hong-Yu Li
- Subjects
Circular dichroism ,Stereochemistry ,Pharmaceutical Science ,Fungus ,Secondary metabolite ,01 natural sciences ,Analytical Chemistry ,Ascomycota ,Drug Discovery ,medicine ,Symbiosis ,Pharmacology ,chemistry.chemical_classification ,biology ,010405 organic chemistry ,Circular Dichroism ,Organic Chemistry ,Fatty acid ,Armillaria ,biology.organism_classification ,Antimicrobial ,Gastrodia elata ,Coculture Techniques ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,chemistry ,Fermentation ,Phoma ,Molecular Medicine ,medicine.drug - Abstract
Co-culturing the endophytic fungus Phoma sp. YUD17001 from Gastrodia elata with Armillaria sp. in liquid nutrient medium resulted in the production of five new secondary metabolites, including two phenolic compounds, phexandiols A and B (1 and 2), three aliphatic ester derivatives, phomesters A-C (3-5), and a known fatty acid (6). The structures and absolute configurations of these compounds were elucidated by the interpretation of data from detailed spectroscopic analysis, Mosher's method, and electronic circular dichroism spectra, together with consideration of the biogenetic origins. None of the five new compounds were detected in single-strain cultures under identical fermentation conditions. The results of this work indicated that the production of 1-5 involved a complicated interaction process. None of the new compounds possessed significant cytotoxicity or antimicrobial activities.
- Published
- 2019
50. Enantioselective Construction of CF3-Containing Spirooxindole γ-Lactones via Organocatalytic Asymmetric Michael/Lactonization
- Author
-
Jianhong Zhao, Wu-Lin Yang, Zhong-Tao Yang, and Wei-Ping Deng
- Subjects
010405 organic chemistry ,Organic Chemistry ,Enantioselective synthesis ,Squaramide ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,chemistry ,Cascade reaction ,Amide ,Intramolecular force ,Physical and Theoretical Chemistry ,Bond cleavage - Abstract
A highly enantioselective Michael/lactonization cascade reaction of 3-hydroxyoxindoles with 3-trifluoroethylidene oxindoles was developed. The use of a cinchona-derived squaramide catalyst is essential in achieving high diastereo- and enantioselectivities. This reaction represents the first example of intramolecular amide C–N bond cleavage and lactonization of 3-hydroxyoxindoles with 3-trifluoroethylidene oxindoles, which provides an efficient and convenient approach to diverse CF3-containing spirooxindole γ-lactones in high yields and good to excellent diastereo- and enantioselectivities.
- Published
- 2019
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.