APPLIED CLAY SCIENCE
·
2023
·
IF 5.6
Li Li,Guanzheng Zhuang,Peng Yuan
Sepiolite can form stable hybrid pigments by immobilizing organic dyes in its microporous structure. Previous investigations demonstrated that the micropores and coordinated water might be responsible for the exceptional color and stability of indigo-sepiolite hybrid pigments. This work reveals the roles of coordinated water in forming hybrid pigments by acid modification. Raw sepiolite was modified by nitric acid at different conditions before use. Then a series of indigo-sepiolite pigments were prepared by indigo and acid-modified sepiolite. Their microstructures were characterized and analyzed by X-ray diffraction, Fourier transform infrared, transmission electron microscopy , and N 2 adsorption-desorption. The color properties of hybrid pigments were evaluated by reflectance spectra and CIE color parameters. Investigations into the chemical stability of pigments were conducted using concentrated HNO 3 and dimethyl sulfoxide. In addition, the photostability of pigments exposed to simulated 30-year illumination in a typical museum was studied. Acid modification of sepiolite contributed to a larger specific surface area and pore volume. However, acid modification resulted in worse color properties and stability due to the removal of coordinated water bonded with octahedral Mg 2+ . These findings confirmed that coordinated water molecules were the key to stabilizing indigo-sepiolite hybrid pigments by forming hydrogen bonds .
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Biomass Conversion and Biorefinery
·
2023
·
IF 4
Xu Tingting,Gao Xin,Li Yuanzhang,Lin Changqu,Ma Peipei,Bai Zhongzhong,Zhou Jun,Wu Hongli,Cao Fei,Wei Ping
Isatis indigotica Fort. root (Ban-lan-gen, IIR), a traditional Chinese medicine (TCM), has an ancient and well-documented history for its medicinal properties. Aside from epigoitrin, indole alkaloids, and their corresponding derivatives as medicinal ingredients, it also contains lots of biomass such as starch. Herein, a new starch was isolated from IIR and the physicochemical properties such as amylose content, moisture content, ash content, morphology, thermal properties, and crystallography were characterized systematically. The amylose content of IIR starch was 19.84 ± 0.85%, and the size and shape of starch granules is ellipsoidal shape with sizes from 2 to 10 μm. IIR starch exhibited a C-type pattern and had 25.92% crystallinity (higher than that of corn starch). The gelatinization temperature of IIR starch was 58.68–75.41 °C, and its gelatinization enthalpy was Δ H gel = 4.33 J/g. After decocting, the IIR’s residues can be used to prepare anhydro-sugars in a polar aprotic solvent. The total carbon yield of levoglucosan (LG), levoglucosenone (LGO), 5-hydroxymethylfurfural (HMF), and furfural (FF) could reach 69.81% from IIR’s decoction residues in 1,4-dioxane with 15 mM H 2 SO 4 as the catalyst. Further, the residues after dehydration were prepared into biochar by thermochemical conversion and the BET surface area of biochar was 1749.46 m 2 /g which has good application prospect in soil improvement and alleviates obstacles of IIR continuous cropping.
研究领域:
药用植物学
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生物质化学
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中药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2022
·
IF 5.122
Li Li,Guanzheng Zhuang,Mengyuan Li,Peng Yuan,Liangliang Deng,Haozhe Guo
Maya blue is a greenish-blue and stable pigment composed of indigo and palygorskite or sepiolite . Previous studies implied that the properties of Maya blue were influenced by different hydroxyl groups in the clay structure, e.g., zeolitic water, coordinated water, and structural hydroxyls. Therefore, an in-depth investigation was planned to analyze the structures and properties of indigo-sepiolite hybrid pigments in this work. Sepiolite materials were heated at 160, 360, 610, and 880 °C to remove zeolitic water, the first coordinated water, the second coordinated water, and structural hydroxyls. A series of Maya blue simulants were prepared by heating the mixture of indigo and sepiolite materials at 180 °C. Reflectance spectroscopy and CIE 1976 color space were employed to characterize color properties and color differences of hybrid pigments. Chemical resistance to concentrated HNO 3 and dimethyl sulfoxide (DMSO), and photostability under visible light were evaluated. Microporous analysis and Fourier transform infrared spectroscopy were applied to study the indigo-sepiolite interaction. Coordinated water was essential for the greenish-blue color and outstanding stability of Maya blue, while zeolitic water and structural hydroxyls did not affect pigments’ properties. Indigo molecules were confirmed to be inserted into sepiolite channels and formed hydrogen bonds with coordinated water at one side. Structural hydroxyls were insignificant for the formation of Maya blue. This work provides a guideline for preparing stable clay-dye hybrid pigments.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
TETRAHEDRON
·
2017
·
IF 2.651
Cuiling Wang,Jiaxu Yan,Mo Du,Joseph A. Burlison,Chi Li,Yanni Sun,Danqing Zhao,Jianli Liu
One step synthesis of the natural product indirubin by reductive coupling of isatin with KBH 4 is described and a possible mechanism for the reaction is proposed. Eleven indirubin derivatives were obtained easily from the corresponding substituted isatin.
研究领域:
有机化学
·
药物化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMBIOCHEM
·
2025
·
IF 2.8
Shiqi Luo,Wei Song,Guipeng Hu,Jian Wen,Xiaomin Li,Cong Gao,Jia Liu,Wanqing Wei,Liming Liu
Graphical Here, we have constructed a dual-enzyme ( Ec TnaA, Ma FMO) cascade pathway for the biosynthesis of indigo from L-tryptophan and enhanced the enzymatic activity of Ma FMO through mechanism-guided rational design. Subsequently, by optimizing promoters and increasing copy numbers to regulate the expression levels of Ec TnaA and Ma FMO D197E , under optimal conditions, E. coli IND-13 achieved the highest yield to date using glucose as the substrate. Indigo is widely used in dyes, medicines and semiconductors materials due to its excellent dyeing efficiency, antibacterial, antiviral, anticancer, anti-corrosion, and thermostability properties. Here, a biosynthetic pathway for indigo was designed, integrating two enzymes ( Ec TnaA, Ma FMO) into a higher L-tryptophan-producing the strain Escherichia coli TRP. However, the lower catalytic activity of Ma FMO was a bottleneck for increasing indigo titers. To overcome this limitation, the enzyme activity of Ma FMO was enhanced through mechanism-guided rational design. The optimal mutant obtained in this study, Ma FMO D197E , whose k cat / K m was 1.34 times that of the wild type, and its specific activity was 2.36 times that of the wild type. In addition, the expression levels of Ec TnaA and Ma FMO D197E were regulated by optimizing the promoters and increasing the copy number to generate the strain E. coli IND-13. Finally, in the optimal fermentation conditions (220 rpm, 0.05 % Tween-80), the strain E. coli IND-13 achieved the indigo titer of 568.52 mg/L in a 5-L bioreactor, with the yield and productivity of 2.62 mg/g and 12.96 mg/L/h (the highest to date), respectively. The results presented here can lay a foundation for further construction of cell factories for indigo and its derivatives with industrial application potential.
研究领域:
合成生物学
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微生物工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2014
·
IF 2.045
Jin-Qiang Liu,Si-Yu Chen,Baoming Ji
The solubility of isatin in eight pure solvents including dichloromethane, toluene, acetone, ethyl acetate, 1,4-dioxane, N,N-dimethylformamide, tetrahydrofuran, and acetonitrile were determined from (278.15 to 333.15) K at atmospheric pressure using the synthetic method. The solubility was determined by a laser monitoring observation technique and found to increase with the rise of temperature. The experimental solubilities were correlated by four models including the ideal solution model, the modified Apelblat equation, λh (Buchowski) equation, and Wilson models with the overall average percentage deviations less than 0.52% in all cases. Thermodynamic functions of the solution of isatin in these solvents including apparent standard enthalpy and entropy of solution were obtained by van’t Hoff plot, and the apparent standard Gibbs energy change of solution was also calculated.
研究领域:
物理化学
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药物化学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2025
·
IF 4.7
Li Li,Qian Liu,Guanzheng Zhuang,Jixing Fan,Peng Yuan,Fei Xu
Thermal treatment is a key step in synthesizing Maya blue pigments. While palygorskite-based Maya blue has been extensively studied, the preparation of sepiolite-based pigments remains underexplored. This study synthesized sepiolite-based Maya blue by heating indigo-sepiolite mixtures at 100–500 °C for 1–72 h, systematically investigating the effects of temperature and duration on pigment color and stability. Mechanistic insights were provided using XRD, surface area and micropore analysis, HRTEM, and FTIR. The optimal preparation conditions were identified as 100–200 °C with heating durations under 8 h. Below 200 °C, increasing temperature and time enhanced the greenish-blue hue and improved chemical and photostability due to the conversion of indigo oligomers to monomers and their diffusion into sepiolite channels. No evidence of strong interactions, such as hydrogen bonding or coordination, was found between indigo and sepiolite. Indigo encapsulation within sepiolite's channels likely explains its stability, while the conversion of intermolecular to intramolecular hydrogen bonds accounts for its coloration. Above 300 °C, indigo degradation caused pigment darkening. HRTEM showed no significant structural changes in sepiolite after heating. Sepiolite's nanostructure, microporosity, and diverse surface groups make it ideal for clay-dye hybrid pigments. These findings advance the understanding and application of sepiolite-based organic-inorganic hybrid materials.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Arabian Journal of Chemistry
·
2024
·
IF 5.3
Changwei Zhang,Hua Yuan,Hong Shen,Chuan Li,Jianzhong Ye,Huaxing Zhang,Chengzhang Wang
The effect of acidolysis time, hydrochloric acid concentration, ozonization time and pH on the yield of indigo were investigated by single factor experiment using dried leaves of Baphicacanthus cusia (Nees) Bremek (DLB) as raw material. On this basis, the technological condition for preparing new indigo extract (NIE) by directional chemical conversion method was optimized by orthogonal experiment. Then, the physiochemical properties of NIE were analyzed by combustion assay, nitric acid assay, thin layer chromatography identification assay, moisture detection and water-soluble pigment observation assay. Moreover, UPLC-Q-TOF-MS/MS technology was utilized to compare chemical composition difference between the NIE and traditional indigo naturalis (TIN). Finally, NIE emulsion was prepared by ultrasound assisted high pressure homogenization method and its stability, antibacterial activity as well as antibacterial mechanism were evaluated. The experimental results showed that optimum process for preparing NIE were hydrochloric acid concentration of 2 %, ozonization time of 3 min, pH of 7 and acidolysis time of 1 h; Under this condition, the content and yield of indigo in the NIE were significantly improved, which could reach up to 42.6 ± 0.28 % and 2.26 ± 0.04 %, separately. NIE possessed similar physiochemical properties with TIN described in Chinese pharmacopoeia 2020, and had more diverse active ingredients than TIN. The prepared NIE emulsion demonstrated excellent stability, whether at dark or bright place, and no matter at low temperature (4 ℃) or room temperature (25 ℃), the particle size, PDI, pH and indigo content of which displayed little variation. In addition, the NIE emulsion owned good inhibitory activity against S. aureus , and its MIC and MBC values were 40 and 80 μg/mL, respectively. Moreover, NIE emulsion exhibited antibacterial effect by influencing cell membrane integrity, Ca 2+ -Mg 2+ -ATPase activity on the cell membrane and intracellular Ca 2+ levels of S. aureus. All of above results will lay the foundation for the green and sustainable utilization of Baphicacanthus cusia (Nees) Bremek.
研究领域:
药用植物学
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天然产物化学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2014
·
IF 5.323
Ruijuan Qu,Bingzhe Xu,Lingjun Meng,Liansheng Wang,Zunyao Wang
As a promising disinfection technique to replace chlorination, ozonation has been demonstrated to be efficient in water treatment . This paper describes an effective way to enhance the ozonation of indigo by using carbon nanotubes functionalized with carboxyl groups (CNTs-COOH) as catalysts. The result of kinetic studies showed that the presence of CNTs-COOH dramatically increased the decolorization rate of indigo. Different types of catalysts were compared to further elucidate the internal mechanism of the catalytic reaction and the special nanostructure and the functional –COOH groups are considered to play an important role in the catalytic ozonation process. Four aromatic intermediate products were identified using an electrospray time-of-flight mass spectrometer and further rationalized by the frontier electron density calculations. Ion chromatography analysis revealed that the nitrogen atom of indigo was released predominantly as ammonium and to a lesser extent as nitrate. The presence of the catalyst CNTs-COOH leads to a higher mineralization degree than single ozonation, as suggested by the total organic carbon (TOC) measurement. Three major carboxylic acids (i.e., oxalic, formic and acetic acids) were also identified as oxidation by-products, and they contributed significantly to the residual TOC after 2 h of ozonation. In addition, the toxicity evolution during the degradation was investigated through two aquatic model species to evaluate the potential ecological risks of the intermediate products.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2017
·Vol. 7
·期 12
·362
·
IF 3.082
Chunjing Hao,Zehua Xiao,Di Xu,Chengbo Zhang,Jian Qiu,Kefu Liu
Textile dyes are some of the most refractory organic compounds in the environment due to their complex and various structure. An integrated resin adsorption/Dielectric Barrier Discharge (DBD) plasma regeneration was proposed to treat the indigo carmine solution. It is the first time to report ectopic regeneration of the saturated resins by non-thermal Dielectric Barrier Discharge. The adsorption/desorption efficiency, surface functional groups, structural properties, regeneration efficiency, and the intermediate products between gas and liquid phase before and after treatment were investigated. The results showed that DBD plasma could maintain the efficient adsorption performance of resins while degrading the indigo carmine adsorbed by resins. The degradation rate of indigo carmine reached 88% and the regeneration efficiency (RE) can be maintained above 85% after multi-successive regeneration cycles. The indigo carmine contaminants were decomposed by a variety of reactive radicals leading to fracture of exocyclic C=C bond, which could cause decoloration of dye solution. Based on above results, a possible degradation pathway for the indigo carmine by resin adsorption/DBD plasma treatment was proposed.Keywords:indigo carmine;resin;Dielectric Barrier Discharge;adsorption;regeneration
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2019
·
IF 4.191
Wenjing Wang,Yuan Wu,Huihui Xu,Yuan Shang,Yichen Chen,Miaoer Yan,Zhaohui Li,David R. Walt
The harvest time of a plant usually affects the yield of its metabolites. Polygonum tinctorium ( Polygonum tinctorium Ait., P. tinctorium ) is an important cultivated plant that produces the natural blue dye indigo and the medicinal metabolite indirubin. To explore the mechanism of indigo and indirubin accumulation, the leaves of P. tinctorium at different harvest times, namely July, August, and October, were investigated by metabolite and de novo transcriptome analyses. The results revealed that the indigo and indirubin content varied at different harvest times. Moreover, their contents were significantly higher (p < 0.05) in August than in either July or October. Transcriptome analysis showed different gene expression patterns of P. tinctorium leaves in August. Almost all the identified differentially expressed genes (DEGs) that were responsible for the biosynthesis of indigo and indirubin, including four anthranilate synthase (AS) genes, two indole-3-glycerolphosphate synthase (IGPS) genes, three tryptophan synthase (TS) genes and seven cytochrome P450 (CYP450) genes were expressed at significantly higher levels in August ( p < 0.05), which correlated with the increase of the two compounds. Overall, the results of this study provide useful information for understanding the accumulation mechanism of indigo and indirubin in P. tinctorium , which may promote the development of agricultural breeding and industrial production of P. tinctorium. Moreover, sequence data obtained by de novo transcriptome sequencing of P. tinctorium provides a platform for future molecular biological studies.
研究领域:
植物学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2016
·
IF 3.138
Xinyi Zhu,Liping Bao,Yong Wei,Jiangquan Ma,Yong Kong
Sodium carboxymethyl cellulose (NaCMC) and chitosan (CS) are successfully combined via amidation, and the obtained product, CMC-CS-A, is used for the adsorption of toxic indigo blue (IB) for the first time. The results of control experiments indicate that the adsorption performance of CMC-CS-A is superior to that of NaCMC, CS, and the composites of NaCMC and CS integrated via electrostatic attractions (CMC-CS-E), which can be attributed to the unique interconnected porous network structure of the as-prepared CMC-CS-A. The mass fraction of CS in the CMC-CS-A is also investigated to achieve the best adsorption of IB, and it reveals that satisfactory removal of IB can be achieved at the CMC-CS-A (50 wt%). Important parameters such as contact time, temperature and initial concentration are discussed in detail in this work. Finally, adsorption isotherms and adsorption kinetics are investigated and compared by using classic models, and the results indicate that the adsorption fits well with the Langmuir isotherm model and the pseudo-second-order kinetic model. It opens a new avenue for the effective and convenient treatment of textile wastewater with integrated natural biopolymers.
研究领域:
环境科学
·
材料科学
·
生物化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）