TETRAHEDRON-ASYMMETRY
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2014
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IF 2.165
Rui-Jie Chen,Gao-Wei Zheng,Yan Ni,Bu-Bing Zeng,Jian-He Xu
A new NADH-dependent carbonyl reductase Rh CR capable of efficiently reducing the ε-ketoester ethyl 8-chloro-6-oxooctanoate (ECOO) to give ethyl ( S )-8-chloro-6-hydroxyoctanoate [( S )-ECHO], an important chiral precursor for the synthesis of ( R )-α-lipoic acid, was identified from Rhodococcus sp. ECU1014. Using recombinant Escherichia coli cells expressing Rh CR and glucose dehydrogenase used for the regeneration of cofactor, 440 g L −1 (2 M) of ECOO were stoichiometrically converted to ( S )-ECHO in a space–time yield of 1580 g L −1 d −1 without the external addition of any expensive cofactor.
研究领域:
生物催化
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酶工程
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合成化学
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生物技术
✓ 已验证
DOI
高影响因子
Food Bioscience
·
2025
·
IF 5.9
Lei Chen,Zhuomin Zhang,Zihan Guan,Jing Sun,Yanhui Sun,Mengmeng Xu,Ka-Hing Wong,Guiyang Shi,Zhongyang Ding
Ergothioneine (EGT) production in Pleurotus tuber-regium was significantly enhanced through Na 2 SeO 3 -induced oxidative stress, in combination with optimized carbon sources and precursor amino acids. Initially, glucose and rhamnose (20 g/L each) as dual carbon sources increased EGT synthesis. Supplementation with 0.75 mM cysteine and 1 mM methionine further promoted EGT biosynthesis by providing essential precursors. Additionally, the introduction of 0.3 mM Na 2 SeO 3 induced oxidative stress, leading to an EGT accumulation of 4.68 mg/g dry weight (DW) in the mycelium and a yield of 35.27 mg/L, representing a 4.25-fold and 162% increases compared to the control, respectively. RNA-Seq analysis revealed that selenium exposure triggered the upregulation of genes involved in antioxidant defense, reinforcing redox homeostasis and driving EGT accumulation. This study highlights the mechanistic role of selenium in modulating antioxidant pathways, offering a promising strategy for enhancing EGT production in the nutraceutical and biotechnological fields.
研究领域:
生物技术
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营养学
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分子生物学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2019
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IF 3.556
Li Long,Xiaolan Hu,Jinpeng Yan,Yifan Zeng,Jiaqi Zhang,Yingwen Xue
It is urgent to explore an effective removal method for perfluorooctanoic acid (PFOA) due to its recalcitrant nature. In this study, a novel chitosan-based hydrogel (CEGH) was prepared with a simple method using chitosan and ethylene glycol through a repeated freezing–thawing procedure. The adsorption of PFOA anions to CEGH agreed well to the Freundlich–Langmuir model with a maximum adsorption capacity as high as 1275.9 mg/g, which is higher than reported values of most adsorbents for PFOA. The adsorption was influenced by experimental conditions. Experimental results showed that the main removal mechanism was the ionic hydrogen bond interaction between carbonyl groups (COO − ) of PFOA and protonated amine (NH + ) of the CEGH adsorbent. Therefore, CEGH is a very attractive adsorbent that can be used to remove PFOA from water in the future.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Water
·
2022
·Vol. 14
·期 7
·1010
·
IF 3.53
Gaoxi Liu,Xiaohui Wei,Peiru Luo,Shuyu Dai,Wenfen Zhang,Yanhao Zhang
The mobility, durability, and widespread use of perfluorinated and polyfluoroalkyl substances (PFAS), notably perfluorooctanoic acid (PFOA), bring about serious contamination of many ground and surface waters. In this study, fluorine and amine-functionalized porous organic polymer (POP-4F) was designed and successfully synthesized as an adsorbent for PFOA removal in water. The characterization results showed that the synthesized material had an amorphous microporous structure, and the BET surface area was up to 479 m2g−1. Its versatile adsorption property was evaluated by batch adsorption experiments using PFOA as a probe. The experiments show that the polymer was able to remove 98% of the PFOA in 5 min from water and then desorb within 3 min in methanol ([PFOA]0= 1 mg L−1; [POP-4F] = 200 mg L−1). Specifically, the adsorption capacity of POP-4F is up to 107 mg g−1, according to the Langmuir fit. The rapid adsorption and desorption of PFOA by POP-4F offers the possibility of economical, environmentally friendly, and efficient treatment of real wastewater.Keywords:perfluoro octanoic acid;porous organic polymer;adsorption removal
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
CHEMICAL ENGINEERING JOURNAL
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2017
·
IF 6.216
Jing Li,Qian Li,Lu-shuang Li,Li Xu
Perfluoroalkyl and polyfluoroalkyl substances are priority contaminants of global concern. It is urgent to remove them from the environment. Adsorption is an efficient approach, but the adsorption capacity and regeneration of adsorbent were not satisfactory. In the present study, mesoporous melamine-formaldehyde resin microsphere (MMFRS) was fabricated through suspension polymerization. Owing to its mesoporous property and large anion-exchange capacity of 0.3 mmol/g, MMFRS was applied to the adsorption of perfluorooctanoic acid, a model target. The sorption kinetics obeyed pseudo-second-order equation and the sorption isotherms fitted both Freundlich and Langmuir models well. MMFRS exhibited a superiority over commercial powdered activated carbon on the adsorption amount. The sorption could reach equilibrium within 24 h. In addition, the material could be easily and economically regenerated by dilute NH 3 ·H 2 O (7.5 mM); a regeneration percentage (>85%) after 20 recycles was obtained. This study provides a facile, environmentally-friendly and low energy-consumption strategy for removal of perfluorooctanoic acid from aqueous solution in waste-water treatment.
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
FOOD HYDROCOLLOIDS
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2024
·
IF 11
Ke Zhang,Lai Jiang,Ru-Kang Chen,Yu Shi,Yu-Gang Shi,Yue-Wen Chen,Rammile Ettelaie,Ping Li
This study aims to construct a versatile film fabricated by gallic acid/octanoic acid-grafted-chitosan (GA/OA- g -CS) for high photodynamic antibacterial and antibiofilm efficacy with blue light (BL, 420 nm) irradiation. First, the GA/OA- g -CS conjugates were synthesized by a green radical-induced grafting reaction in the redox system composed of ascorbic acid/hydroxyl peroxide (AA/H 2 O 2 ). Then, the molecular structural and physicochemical characteristics of the conjugates, as well as the mechanisms of the free radical grafting reaction were further studied. Ascorbate radical ( Asc • − ) and hydroxyl radical (•OH) were produced in the AA/H 2 O 2 system, and •OH reacted with CS to produce CS macro-radicals (•CS). UV–vis, Fourier transform infrared, nuclear magnetic resonance spectroscopy, X-ray diffraction (XRD), and thermogravimetric analysis confirmed that GA/OA was attached onto CS through •OH. Notably, the films constructed by GA/OA- g -CS exhibited robust multi-modal functionalities, including intriguing bacteria-capturing and contact-killing, as well as BL-driven photodynamic sterilization, ascribed to the inherent merits based on the massive photoactive GA, hydrophobic and high membrane affinity of OA within the CS chains. As a result, the GA/OA- g -CS (2:1) film plus BL irradiation can efficiently eradicate Escherichia coli ( E. coli ), Staphylococcus aureus ( S. aureus ) and their biofilms. After BL irradiation for 30 min, the GA/OA- g -CS (2:1) film showed a reduction of 5.2 Log CFU/mL against E. coli . More importantly, the film with BL irradiation can efficiently not only inhibit the formation of biofilms but also jeopardize the matured biofilms. This research provides a potential platform and promises for applications in active and intelligent food packaging.
研究领域:
食品科学
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生物材料
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
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2015
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IF 2.719
Qi Liu,Aizhen Huang,Nan Wang,Guan Zheng,Lihua Zhu
Analysis of perfluorooctanoic acid (PFOA) usually requires a combination of high-performance liquid chromatography and mass spectrometry , which is expensive and time-consuming. In the present work, water-soluble CdS quantum dots (QDs) were employed to develop a simple and rapid fluorometric method for the determination of PFOA. Strongly fluorescent CdS QDs were prepared by using 3-mercaptopropionic acid (MPA) as a stabilizer . It was observed that PFOA strongly quenched the fluorescence emission of the MPA-CdS QDs because PFOA promotes the aggregation of MPA-CdS QDs through a fluorine–fluorine affinity interaction. Under optimum conditions, the fluorescence intensity of MPA-CdS QDs was observed to decrease linearly with an increase in the concentration of PFOA from 0.5 to 40 μmol L −1 , with a limit of detection of 0.3 μmol L −1 . This new method was successfully implemented for the analysis of PFOA-spiked textile samples, with recoveries ranging from 95% to 113%.
研究领域:
分析化学
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环境科学
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
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2020
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IF 3.795
Peng Yang,Xianzhi Hu,Futing Zi,Baomin Yang,Qiang Wang,Yunlong Chen,Shuliang Chen
Because it is difficult to hydrophobically agglomerate fine kaolinite particles to obtain stronger, larger flocs using only dodecylamine (DDA) as a flocculant , octanoic acid (OA) was used as a synergistic flocculant to improve DDA-induced fine-kaolinite particle agglomeration. Particle settlement tests were conducted to study flocculation and synergistic flocculation behaviours of fine kaolinite particles for different DDA and/or OA concentrations. Results showed that OA strengthened DDA-induced particle agglomeration. Aggregate sedimentation rates and Stokes’ equivalent diameters exceeded 21.7 m/h and 84.4 µm, respectively. A clearer kaolinite suspension was obtained and a more compact aggregate layer accumulated within 3 min. Contact angles and Fourier-transform infrared (FTIR) spectroscopy were used to investigate kaolinite hydrophobicity before and after hydrophobisation and mechanisms of DDA and/or OA interactions with the kaolinite surface. Results suggested that faster sedimentation and larger equivalent-diameter aggregates were both related to significantly increased kaolinite-surface hydrophobicity. FTIR data confirmed that enhanced kaolinite surface hydrophobicity was owed to DDA and OA physisorption . The kaolinite micro-particle aggregation mechanism was analysed by SEM images. Kaolinite particle self-aggregation changed after OA was adsorbed on the kaolinite Si–O basal plane. Owing to DDA/OA synergistic effects, kaolinite particles hydrophobically agglomerated by actions of Al–O/Al–O and Al–O/Si–O faces, thereby promoting fine-kaolinite particle agglomeration and sedimentation. Study findings could lead to development of enhanced water-purification methods.
研究领域:
矿物加工工程
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环境科学与工程
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2019
·
IF 3.621
Li Song,Bao Zhang,Ge Gao,Chunsheng Xiao,Gao Li
Herein, Pluronic F127 (PEO 99 -PPO 65 -PEO 99 ) end functionalized with α-lipoic acid (LA) (F127-LA) was synthesized and used for preparation of “single-component, multi-responsive” hydrogels through the photo cross-linking of LA components. The F127-LA hydrogels not only possessed thermo- and reduction- double responsiveness, but also demonstrated self-healing properties under UV irradiation due to the existence of dynamic disulfide bonds. The rheological and mechanical properties of the hydrogels can be adjusted by their concentration. The F127-LA hydrogels presented a swelling ratio decrease from 25 °C to 37 °C due to a lower critical solution temperature (LCST)-type thermo-responsive volume phase transition. The bovine serum albumin (BSA) was loaded into F127-LA hydrogels, and their drug release behavior can be regulated by surrounding temperature and reducing agent concentration. The volume shrinkage of the hydrogels promoted the sustained release of BSA above volume phase transition temperature. Cytocompatibility assay of L929 mouse fibroblasts showed that cellular metabolic activity were merely affected by F127-LA, even at concentrations up to 1000 mg L −1 . This study thus provided a very promising route for the preparation of multifunctional hydrogels.
研究领域:
材料科学
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生物医学工程
·
药物递送
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2016
·
IF 3.698
Lina Zhou,Mengjie Xia,Li Wang,Hui Mao
As a persistent organic pollutant in the environment, perfluorooctanoic acid (PFOA) has been extensively investigated. It can accumulate in food chains and in the human body. This work investigated the effect of PFOA on wheat ( Triticum aestivum L.) germination and seedling growth by conducting a germination trial and a pot trial. A stimulatory effect of PFOA on seedling growth and root length of wheat was found at <0.2 mg kg −1 , while >800 mg kg −1 PFOA inhibited germination rate, index, and root and shoot growth. In the pot trial, PFOA concentration in root was double that in the shoot. Soil and plant analyzer development (SPAD) and plant height of wheat seedling were inhibited by adding 200 mg kg −1 PFOA. Proline content and POD activity in wheat seedlings increased as PFOA increased, while CAT activity decreased. Using logarithmic equations, proline content was selected as the most sensitive index by concentration for 50% of maximal effect (EC 50 ). Hence, the tolerance of wheat seedlings to PFOA levels could be evaluated on the basis of the physiological index.
研究领域:
环境科学
·
植物生理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Wenli Yao,Mingzhe Li,Changduo Sun,Yanlong Liu,Mengling Ma,Fengjuan Chen,Lei Zhou,Yian Zheng
Removal of perfluorinated compounds (PFCs) from the environment is a major challenge due to their refractory, persistent and bioaccumulative properties. In this study, trace Co coupled via Co–P coordination and tourmaline (TM) doped g-C 3 N 4 was fabricated (marked as Co/TM/g-C 3 N 4 ) and used as the catalyst for activating peroxymonosulfate (PMS) to remove emerging PFOA under visible light irradiation. Several affecting parameters were systematically investigated, inlcuding Co/TM/g-C 3 N 4 dosage, PMS concentration, initial pH, as well as coexisting Cl − , HC O 3 − , H 2 P O 4 − , N O 3 − and humic acid . Under the conditions of 0.5 g/L Co/TM/g-C 3 N 4 , 2.5 g/L PMS and pH 3.0, the developed synergistic system had the ability for 81.11% removal of PFOA within 4 h, 67.64% removal after the fourth run, and also could be effectively applied in actual water bodies. During the degradation process , π-π*, N–C N and graphite N played the vital role, with the final defluorination rate of 31.12% at 4 h. Free radical quenching and quantitative analysis, as well as electron paramagnetic resonance was used to verify the free radical and non-free radical pathways for PFOA removal, with the findings that S O 4 • − (2.61 μM at 1 h), •OH (0.067 μM at 4 h), O 2 • − , h + , and O 1 2 were involved with possible time-dependent. By liquid chromatography-mass spectrometry analysis, the short-chain intermediates of C3–C7 were proposed and identified. From this study, trace Co coupled and TM doped g-C 3 N 4 demonstrated higher catalytic potential to activate PMS for visible-light synergistic PFOA removal, with the expectation of achieving a cleaner water environment for human beings.
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Ruiming Liu,Xiaosen Pan,Zijun Xu,Lin Cheng,Dongsheng Ma,Lulu Cai,Xiao-Gen Xiong,Liyu Zheng,Qin Yue
Stretchable sensors have attracted an increasing interests in electronic skin, motion monitoring, medical care, and human-computer interaction. The traditional polymer-based elastomers possess excellent mechanical properties, however, are non-recyclable and difficult-to-degrade. Poly(thioctic acid) (PTA) offers recyclability through reversible disulfide bond polymerization, its poor resilience and conductivity limit practical applications. Herein, the synthesis of a recyclable polysulfide network has been pioneered with super-stretchability, remarkable resilience, electrical stability, and self-healing ability through molecular structure design. By modifying the thioctic acid (TA) repeating units with cationic chains to obtain cationic thioctic acid (C 15 H 25 N 2 O 2 S 2 Br, TAB), and subsequently co-polymerizing it with PTA, the recyclable and super-stretchable Poly(TA- co -TAB) are generated with high resilience and electronic stability. The resulting material achieves tunable stretchability (360–1700%), high sensitivity (GF = 16.2), fast response/recovery (117/108 ms), and stability (>1500 cycles at 100% strain). Notably, the material can be fully recycled via a simple alkaline dissolution-acid extraction process, showcasing its environmental sustainability.
研究领域:
材料科学
·
高分子化学
·
柔性电子学
·
可持续技术
·
传感器技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）