Biotechnology for Biofuels and Bioproducts
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2022
·Vol. 15
·期 1
·1-10
·
IF 0
Hua Xia,Zhang ChenHui,Han Jian,Xu Yong
Background Hydroxyl acid is an important platform chemical that covers many industrial applications due to its dual functional modules. At present, the traditional technology for hydroxyl acid production mainly adopts the petroleum route with benzene, cyclohexane, butadiene and other non-renewable resources as raw materials which violates the development law of green chemistry. Conversely, it is well-known that biotechnology and bioengineering techniques possess several advantages over chemical methods, such as moderate reaction conditions, high chemical selectivity, and environmental-friendly. However, compared with chemical engineering, there are still some major obstacles in the industrial application of biotechnology. The critical issue of the competitiveness between bioengineering and chemical engineering is products titer and volume productivity. Therefore, based on the importance of hydroxyl acids in many fields, exploring a clean, practical and environmental-friendly preparation process of the hydroxyl acids is the core purpose of this study. Results To obtain high-purity hydroxyl acid, a microbiological regulation for its bioproduction by Gluconobacter oxydans was constructed. In the study, we found a critical point of chain length determine the end-products. Gluconobacter oxydans catalyzed diols with chain length ≤ 4, forming hydroxyl acids, and converting 1,5-pentylene glycol and 1,6-hexylene glycol to diacids. Based on this principle, we successfully synthesized 75.3 g/L glycolic acid, 83.2 g/L 3-hydroxypropionic acid, and 94.3 g/L 4-hydroxybutyric acid within 48 h. Furthermore, we directionally controlled the products of C5/C6 diols by adjusting pH, resulting in 102.3 g/L 5‑hydroxyvaleric acid and 48.8 g/L 6-hydroxycaproic acid instead of diacids. Combining pH regulation and cell-recycling technology in sealed-oxygen supply bioreactor, we prepared 271.4 g 5‑hydroxyvaleric acid and 129.4 g 6-hydroxycaproic acid in 6 rounds. Conclusions In this study, a green scheme of employing G. oxydans as biocatalyst for superior-quality hydroxyl acids (C2–C6) production is raised up. The proposed strategy commendably demonstrated a novel technology with simple pH regulation for high-value production of hydroxyl acids via green bioprocess developments.
研究领域:
生物化学
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绿色化学
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生物工程
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DOI
PubMed
Biomaterials Science
·
2018
·Vol. 6
·期 5
·1227-1237
·
IF 5.831
Qianwen Li,Donghui Wang,Jiajun Qiu,Feng Peng,Xuanyong Liu
Hard tissue implant materials which can cause a suitable alkaline microenvironment are thought to be beneficial for stimulating osteoblast differentiation while suppressing osteoclast generation. To make the local pH around the interface between materials and cells controllable, we prepared a series of Mg–Fe layered double hydroxide (LDH) films on acid-etched pure titanium surfaces via hydrothermal treatment. By adjusting the Mg/Fe proportion ratio, the interlayer spacing of Mg–Fe LDHs was regulated, making their OH− exchange abilities adjustable, and this ultimately resulted in a microenvironment with a controllable pH value. In vitro experiments demonstrated that the Mg–Fe LDH film-modified titanium surface possessed good biocompatibility and osteogenic activity, especially the Mg–Fe LDH film with Mg/Fe proportion ratio of 4, which could form a suitable alkaline microenvironment for the growth and osteogenetic differentiation of stem cells. These results demonstrate the potential application of the prepared Mg–Fe LDH films in enhancing the osteogenesis of implant materials while providing a new way into the design of controllable alkaline environment.
研究领域:
生物材料学
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细胞生物学
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医学工程
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DOI
PubMed
高影响因子
LANGMUIR
·
2021
·
IF 3.882
Liwei Zhao,Ming Gong,Jian Yang,Jinlou Gu
The construction of a biomimetic ionic channel is of great significance for the fabrication of smart biodevices or logic circuit. Inspired by the selective permeability of the cell membrane toward bioions, a light-induced and pH-modulated artificial nanochannel is herein prepared by integrating the multistimuli-response molecule of carboxylated spiropyran (SP-COOH) into the frameworks of NU-1000 (Zr-based MOFs defined by Northwestern University). The loading density of the SP-COOH could reach as high as 7 wt % while keeping unchanged crystallinity and high porosity. Thanks to the precise matching of pore size of NU-1000 and molecular dimensions of SP-COOH, the loaded molecules could proceed free and reversible for isomerization between the hydrophilic and hydrophobic states. The ion-switchable characteristics of the channel are implemented by the amphiphilic change of the light-controlled gate molecule. Additionally, in the hydrophilic state, the channel presents reversible affinity toward cations or anions due to the reverse charge state induced by pH, thus constructing a pH-controlled subgate. Taking [Ru(NH3)6]3+ and [Fe(NH3)]3– as the model cation and anion, their redox peak currents occur as reversible change under different signal combinations of light and pH. Moreover, in accordance with the ionic selective permeability, several logic circuits/devices are designed to display the relationships between exogenous stimuli and ionic transportations in a computer language, prefiguring their wide application prospects in electronic devices and life sciences.
研究领域:
材料科学
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生物医学工程
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化学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
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2018
·Vol. 8
·期 73
·41956-41965
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IF 2.936
Jingxian Huang,Wenwei Huang,Yin Chen,Yu Shrike Zhang,Jinshuang Zhong,Yan Li,Jianhua Zhou
In this work, we present a novel class of uniform eccentric magnetic microcapsules based on polydimethylsiloxane (PDMS) for magnetic resonance imaging (MRI)-guided local injection and pH-regulated drug release. The microcapsules contained magnetic nanoparticles in their PDMS shells, which allowed them to be easily tracked by MRI during administration. Besides, they showed pH-dependent drug release profiles due to dissolution of the embedded magnetic nanoparticles in acidic solutions. Moreover, by tuning the mass fraction of the magnetic nanoparticles, we could further regulate the release rate of drug molecules from them. As a demonstration, we investigated the delivery of cis-platinum using the microcapsules through an in vitro cell test, which confirmed the pH-controlled release of the drug in phantom tissues. Our study suggests that this type of eccentric magnetic microcapsules could be simultaneously employed as a potential imaging contrast and a smart drug delivery system, holding great potential for guided local therapy.
研究领域:
生物医学工程
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材料科学
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医学影像
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DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
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2017
·
IF 4.857
Lei Mei,Cong-zhi Wang,Liu-zheng Zhu,Zeng-qiang Gao,Zhi-fang Chai,John K. Gibson,Wei-qun Shi
The reaction of uranyl nitrate with terephthalic acid (H2TP) under hydrothermal conditions in the presence of an organic base, 1,3-(4,4′-bispyridyl)propane (BPP) or 4,4′-bipyridine (BPY), provided four uranyl terephthalate compounds with different entangled structures by a pH-tuning method. [UO2(TP)1.5](H2BPP)0.5·2H2O (1) obtained in a relatively acidic solution (final aqueous pH, 4.28) crystallizes in the form of a noninterpenetrated honeycomb-like two-dimensional network structure. An elevation of the solution pH (final pH, 5.21) promotes the formation of a dimeric uranyl-mediated polycatenated framework, [(UO2)2(μ-OH)2(TP)2]2(H2BPP)2·4.5H2O (2). Another new polycatenated framework with a monomeric uranyl unit, [(UO2)2(TP)3](H2BPP) (3), begins to emerge as a minor accompanying product of 2 when the pH is increased up to 6.61, and turns out to be a significant product at pH 7.00. When more rigid but small-size BPY molecules replace BPP molecules, [UO2(TP)1.5](H2BPP)0.5 (4) with a polycatenated framework similar to 3 was obtained in a relatively acidic solution (final pH, 4.81). The successful preparation of 2–4 represents the first report of uranyl–organic polycatenated frameworks derived from a simple H2TP linker. A direct comparison between these polycatenated frameworks and previously reported uranyl terephthalate compounds suggests that the template and cavity-filling effects of organic bases (such as BPP or BPY), in combination with specific hydrothermal conditions, promote the formation of uranyl terephthalate polycatenated frameworks.
研究领域:
化学
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材料科学
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DOI
高影响因子
INORGANIC CHEMISTRY
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2020
·
IF 4.825
Wan Jiang,Yuyuan Bai,Qinzhen Li,Xiean Yao,Hui Zhang,Yongbo Song,Xiangming Meng,Haizhu Yu,Manzhou Zhu
An understanding of the response of nanomaterials to specific environmental parameters is an essential prerequisite for their practical use, especially in living systems. Herein, we disclose the preparation of a water-soluble nanocluster Au16(SR)12 (SR denotes deprotonated captopril) and its characterization by a combination of theoretical (e.g., density functional theory calculations) and experimental (UV–vis, electrospray ionization mass spectrometry, etc.) methods. Interestingly, Au16(SR)12 was found to convert to Au18(SR)14 under acidic conditions, while the reverse conversion from Au18(SR)14 to Au16(SR)12 occurred upon the addition of base. A mechanistic investigation determined this pH regulation to originate from the distinct steric and electrostatic properties of these two clusters. This study is the first to report the susceptibility of Au18(SR)14 and Au16(SR)12 to pH, and the distinct pH stability unambiguously reveals the importance of size-tracking of nanomaterials in living systems for future clinical applications.
研究领域:
纳米材料
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生物化学
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理论计算
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DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
·
IF 5.316
Yi Peng,Juntao Wang,Ying Yan,Wenlei Wang,Hongbo Xiao
In this work, a high content of pyrrole nitrogen carbon nitride (HPCN)-SnS 2 has been successfully constructed with −C═Sn− chemical bond as the interface framework. The charge state of Sn species was adjusted by β particles to obtain controllable sulfur defects onto the HPCN-SnS 2 through electron beam irradiation (EBI). The composites exhibited excellent photocatalytic oxidation capacity of As(Ⅲ) and adsorption capacity of As(Ⅴ). It is confirmed that the optimized HPCN-SnS 1.38 can remove the total As concentrations below 0.40 mg/L within 80 min. Additionally, the effect of various conditions (pH value and type of anions) was evaluated using degradation experiments, and HPCN-SnS 1.38 could be reused at least 5 times without an obvious reduction in the photocatalysis and adsorption performances. Based on the experimental results, the photocatalytic mechanism of As(Ⅲ) by HPCN-SnS 2 after electron beam irradiation was studied. Free radical quenching experiments and electron paramagnetic resonance (EPR) showed that the oxidation of As(III) under visible light is mainly controlled by •O 2 − and •OH, and •OH is converted from •O 2 − under acidic conditions.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Shiwei Xie,Chang Li,Hui Zhan,Wei Shao,Yuanxin Zhao,Peng Liu,Peng Liao
Fe-based replacement and precipitation are promising methods for removal of copper ethylenediaminetetraacetic acid (Cu(II)-EDTA) but are limited by the necessity of controlling pH and dissolved oxygen. The details of the decomplexation mechanism also remain unclear. The present work investigated an anoxic iron electrocoagulation process capable of automatically modulating anoxic conditions and solution pH during exposure to air and thus promoting the rapid and thorough decomplexation of Cu(II)-EDTA. Dissolved Fe (II), rather than Fe(II)-bearing minerals, was found to be primarily responsible for the reduction of Cu(II)-EDTA to Cu(I)-EDTA and for the subsequent replacement reaction to generate free Cu(I) ions within the initial pH range of 2–7. The Cu(I) was primarily precipitated as Cu 2 O on the surface of green rust and magnetite as the pH was increased. The aeration of these Fe-containing precipitates released free Cu(I) ions instead of chelated Cu into solution, allowing for recycling of the Cu. This release of Cu(I) was likely induced by the pH decrease during aeration. This study provides important insights regarding the reductive decomplexation of chelated Cu(II) and the recovery of Cu via anoxic iron electrocoagulation, which is a promising green approach to recycling Cu from wastewater.
研究领域:
环境科学
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废水处理
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
·
IF 7.312
Tingting Zhang,Yi Li,Xudong Zhao,Weihua Li,Xiuyun Sun,Jiansheng Li,Rui Lu
During the boronic acid production process, boronic acid emission causes considerable loss of resources and water pollution. At present, adsorption is the preferred technology to treat boron pollution. Although conventional adsorbents are simple and effective, their regeneration and recovery are challenging, which hinder their wide-scale application. Considerable research efforts have been devoted to resolving the two issues mentioned above. Herein, a novel boron-adsorbing magnetic material with a cis -diol structure possessing boronate affinity was prepared. 3-Hydroxytyramine hydrochloride auto-polymerization (PDA), magnetic graphene oxide (GO) synthesis, polyethylenimine (PEI) self-assembly, and a 3,4-dihydroxyphenylpropionic acid (DHHA) covalent bonding procedure were conducted to synthesize a Fe 3 O 4 /PDA/GO/PEI/DHHA nanocomposite. This nanocomposite exhibited excellent adsorption performance and was easily recycled using an external magnetic force. The boronic acid was separated and recovered by simply adjusting the pH of the solution. The nanocomposite’s adsorption capacity reached 91.46 mg g - 1 at 30 °C with 4-formylphenylboronic acid (FPBA) as a model compound. Besides, the adsorption capacity of the nanocomposite was maintained at >89% of its original value even after five cycles. It was confirmed that the adsorption was primarily a thermochemical reaction controlled by entropy change. Thus, this novel adsorbent can be used for boron removal because it exhibits significant boronate affinity and high regeneration ability and is easy to recycle.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Xingyu Lin,Yong Zhang,Ziteng Yang,Wenjian Yue,Ruoxin Zhang,Jie Qi,Hongsheng Lu
pH-regulated wettability transformation materials have gained increasing attention attributing to the capacity for sustainable oil-water separation. In this work, a smart quartz sand (OD-SiO 2 @sand) with controllable wettability was designed as a filter media for efficient oil-water mixtures and water in oil emulsions separation. The OD-SiO 2 @sand was synthesized by grafting nano-silica and modifying with two silane couplers, including N, N-Diethyl-3-(trimethoxysilyl)− 1-propanamine (DTP) and trimethoxy(octyl)silane (OTMS). OD-SiO 2 @sand featured superhydrophobicity with a water contact angle (WCA) of 151.6°, which suggests selective separation capacity for oil and high permeation flux up to 4018 L.m −2 ∙h −1 . Meanwhile, OD-SiO 2 @sand exhibits superhydrophobicity and hydrophilicity in neutral and acidic solutions resulting from the reversible protonation of grafted DTP, which was revealed by 1 H NMR and molecular dynamics simulations. OD-SiO 2 @sand posed controllable oil-water separation performance, which remains superhydrophobicity with a WCA of 150.4° after 10 cycles of filtration processes upon pH regulation. Furthermore, OD-SiO 2 @sand demonstrated efficient demulsification and separation capacity for various water in oil emulsions, achieving a purified oil size of less than 10 nm and a permeation flux up to 1850 L.m −2 ∙h −1 . Thus, OD-SiO 2 @sand shows promising applicability in the field of oil recovery and oil quality improvement.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FLUORESCENCE
·
2025
·
IF 3.1
Xue Weijian,Ling Xiangyu,Li Huiqian,Liu Yuhang,Zhao Bing,Yin Yanbing
In this work, two chain aromatic hydrocarbon derivatives 1 – 2 , which are constructed by linking two 3 H-imidazo[4,5- b ]pyridine moieties through phenyls and oxygen bridges, were designed and synthesized. The aggregation and disaggregation behavior of these sensors could be modulated by pH, as evidenced by H 1 NMR, fluorescence spectrum and DLS, attributable to the altered deprotonation of the 3 H-imidazo[4,5- b ]pyridine cores. An increase in the sensor concentration leads to the reemergence of aggregation, correspondingly diminishing the fluorescence intensity. Polyaromatic aromatic hydrocarbons (PAHs), known for their luminescent characteristics, demonstrate sustained luminescence even at high concentrations of 10 − 3 M. Notably, the fluorescence of PAHs are effectively quenched upon mixed with 7 × 10 − 5 M aggregated sensor 1 or 10 − 4 M aggregated sensor 2 . Aggregation is identified as the predominant mechanism for fluorescence quenching, the finding corroborated by fluorescence spectroscopy and DLS measurements. Based on computational studies and mechanistic evaluations, sensors 1 and 2 emerge as promising candidates for serving as efficient fluorescence quenchers for polycyclic aromatic hydrocarbons. Graphic
研究领域:
化学
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环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yang Hu,Tianyou Cui,Zhihong Yang,Lu Ren,Li Luo,Mengqian Zhao,Mingjie Jin,Xuwei Long
Sophorolipids (SLs) show great potential application in many fields as an alternative to chemically synthesized surfactants. However, their poor water solubility limits industrial applications in many fields. In this study, a new environmentally friendly strategy based on acid-induced chemical modifications has been developed to prepare and isolate water-soluble SLs from natural SLs that not dissolve or precipitate in fermentation broth. Over 70 % of SLs were obtained as sediments from fermentation broth after chemical modification at a pH of 1 at 120 °C for 5 min. The obtained SLs demonstrated excellent pH-regulated water solubility, superior foaming ability, and comparable surface activities with natural SLs. The involved mechanism of the present process was attributed to the generation of glucolipids with excellent water solubility. The present findings are conducive to preparing water-soluble SLs, addressing the problem that SLs cannot be recovered from fermentation broths via acid-induced precipitation in certain case.
研究领域:
生物化学
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环境科学
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工业应用
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）