INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2016
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IF 2.567
Binglin Li,Jiao Wang,Xiaoli Zhang,Binxia Zhao
Phospholipase D (PLD) was immobilized in a simple and effective way by adsorption and precipitation of the enzyme, followed by chemical cross-linking to form an “enzyme net” covering the surface of nonporous silicon dioxide nanoparticles. For catalyzing transphosphatidylation to produce phosphatidylethanolamine (PE), at pH 6.0 and 35 °C (the optimum operational conditions), the specific activity of immobilized PLD reached 15872 U/gprotein, which was approximately 1.15 times higher than the maximum value of specific activity of free PLD (13813 U/gprotein). A kinetic study demonstrates immobilized PLD had increases in catalytic activity and enzyme–substrate affinity. In addition, the thermostability and pH tolerance were significantly enhanced compared with free PLD. The half-life of immobilized PLD was significantly increased from 30 to 70 days at 4 °C (approximately 2.3 times). This novel method has been proven to be suitable for the production of robust biocatalysts.
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Analytical Methods
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2017
·Vol. 9
·期 43
·6131-6138
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IF 1.9
Xiangyu Wang,Huihui Wu,Rongying Luo,Donghai Xia,Zhengjin Jiang,Hai Han
D-amino acids are currently paid attention to as new physiologically active substances. Foodstuffs and beverages containing D-amino acids are a matter of interest. Until now, the profiles of D-amino acids have not been reported in natural and fermented teas except theanine. In this study, an off-line 2D-HPLC method combining a Gemini C18 column and a CHIRALPAK® IC-3 column or a self-prepared poly(MQD-co-HEMA-co-EDMA) monolithic capillary column was employed for the separation and detection of D-amino acids in tea samples with the co-existence of a large amount of L-amino acids. The free amino acid fractions in longjing, black, oolong, and pu-erh tea samples were separated and collected after pre-column derivatization using 9-fluorenylmethoxycarbonyl (FMOC) chloride in the reversed-phase mode, and then were concentrated and separated to D- and L-forms on a chiral column. Among them, the D-form of isoleucine (Ile) (1.0–1.6%), alanine (Ala) (0.1–0.8%), phenylalanine (Phe) (0.1–0.4%), valine (Val) (0.2–0.3%), serine (Ser) (0.1–0.2%), aspartic acid (Asp) (0.2%), and proline (Pro) (0.1%) were detected in longjing and oolong teas. Differences between natural tea and fermented tea in the profiles of D-amino acids as well as the total amino acids were also observed. The results provided useful information for the bio-function research of D-amino acids in tea.
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BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
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2015
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IF 2.297
Li Ma,Xia Gong,Ge Kuang,Rong Jiang,Rongchun Chen,Jingyuan Wan
Sesamin has been described to exert anti-oxidant and anti-inflammatory properties. In present study, we investigated the potential effects and mechanisms of sesamin on lipopolysaccharide (LPS)-induced fulminant hepatic failure (FHF) in d -galactosamine (D-GalN)-sensitized mice. Our results showed that pretreatment with sesamin dose-dependently improved LPS/D-GalN-induced mortality and liver injury as indicated by reduced serum levels of aminotransferases and alleviated pathological damage as well as hepatocyte apoptosis in mice. Additionally, sesamin markedly attenuated LPS/D-GalN-induced adhesion molecules expression, and decreased neutrophils recruitment. Furthermore, sesamin inhibited LPS-induced tumor necrosis factor-alpha (TNF-α) production, p38 mitogen-activated protein kinases (MAPK) and NF-κB activation, and Toll like receptor (TLR) 4 expression in mice and in RAW264.7 macrophage cells. In summary, these results demonstrate that sesamin protects mice from LPS-induced FHF and the molecular mechanisms may down-regulate the expression of TLR4, block MAPK and NF-κB activation, decrease the production of TNF-α.
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Chemical Biology & Drug Design
·
2015
·Vol. 87
·期 4
·499-507
·
IF 2.485
Xuebao Wang,Di Chen,Shufang Yu,Zaikui Zhang,Yu Wang,Xiaolu Qi,Weitao Fu,Zixin Xie,Faqing Ye
A series of tetrahydrobenzothieno[2,3-d]pyrimidine derivatives were designed, synthesized, and evaluated as inhibitors of FGFR1. These analogs were synthesized via Gewald's reaction under mild conditions. The structures of the synthesized compounds were characterized by spectroscopic data (IR, 1 H NMR and MS). Their antitumor activities were evaluated against H460, A549 and U251 cell lines in vitro . Results revealed that the tested compounds showed moderate antitumor activities. Structure–activity relationship analyses indicated that compounds with an aromatic ring substituted in the C-2 position or with larger molecules such as 3g , 4c , and 7 were more effective than others. The compound, 3g (78.8% FGFR1 inhibition at 10 μ m ), was identified to have the most potent antitumor activities, with IC 50 values of 7.7, 18.9, and 13.3 μ m against the H460, A549, and U251 cell lines, respectively. Together, the results suggested that tetrahydrobenzothieno[2,3-d]pyrimidine derivatives may serve as a potential agent for the treatment of FGFR1-mediated cancers.
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BIOMACROMOLECULES
·
2015
·
IF 5.75
Piming Ma,Long Jiang,Pengwu Xu,Weifu Dong,Mingqing Chen,Piet J. Lemstra
In this work we report the in situ preparation of fully biobased stereocomplex poly(lactide) (SC-PLA) nanocomposites grafted onto nanocrystalline cellulose (NCC). The stereocomplexation rate by compounding high-molar-mass poly(d-lactide) (PDLA) with comb-like NCC grafted poly(l-lactide) is rather high in comparison with mixtures of PDLA and PLLA. The rapid stereocomplexation was evidenced by a high stereocomplexation temperature (Tc-sc = 145 °C) and a high SC crystallinity (Xc-sc = 38%) upon fast cooling (50 °C/min) from the melt (250 °C for 2 min), which are higher than currently reported values. Moreover, the half-life crystallization time (175–190 °C) of the SC-PLA was shortened by 84–92% in comparison with the PDLA/PLLA blends. The high(er) stereocomplexation rate and the melt stability of the SC in the nanocomposites were ascribed to the nucleation effect of the chemically bonded NCC and the “memory effect” of molecular pairs in the stereocomplex melt because of the confined freedom of the grafted PLLA chains.
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Journal of Physical Chemistry C
·
2015
·
IF 4.772
Yongxin Tao,Xiaogang Gu,Linhong Deng,Yong Qin,Huaiguo Xue,Yong Kong
We report a Cu2+-modified β-cyclodextrin, Cu2-β-CD, that was self-assembled on poly(l-glutamic acid) (P-l-Glu) for chiral recognition of d-tryptophan (d-Trp). Cu2+ formed binuclear hydroxy-bridge (Cu(OH)2Cu) at the wider opening of the cavity of β-CD and acted as a cap to prevent high-energy water molecules from being released while forcing Trp isomers to enter through its narrower opening. Because H-bonds were favored to form between the high-energy water molecules and the amino groups of d-Trp inside the cavity of β-CD, d-Trp was thus recognized. The recognition capability of the Cu2-β-CD appeared to depend on the way the Cu2-β-CD self-assembled onto P-l-Glu, preferring via H-bonds rather than via electrostatic interactions, because electrostatic interactions between P-l-Glu and Cu(OH)2Cu could alter the configuration of the Cu2-β-CD cavity, resulting in weakened H-bonds between high-energy water molecules and d-Trp.
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ELECTROCHIMICA ACTA
·
2025
·
IF 5.6
Hongdi Zheng,Liuyan Zhang,Yingying Li,Binkai Yuan,Shixuan Wang,Zeyi Guan,Gengzhe Shen,Guibin Tan,Yanmei Zhang
A honeycomb-like porous self-supporting Ni-Al(G) electrode was successfully prepared by low-pressure cold spraying combined with heat treatment. The main components of the electrode were Ni and NiAl. Graphene was uniformly dispersed throughout the electrode, exhibiting a 3-D distribution, which increased the active site of electrode and improved the electron exchange rate. The electrochemical properties of the Ni-Al(G) electrode were characterized using 6 M KOH. As a result, the Ni-Al(G) electrode requires only an overpotential of 130 mV to achieve a current density of 100 mA cm −2 , and a Tafel slope of 35.5 mV dec −1 . In addition, the electrode exhibited excellent stability. The addition of graphene and the honeycomb-like porous structure of the Ni-Al(G) electrode resulted in an excellent hydrogen evolution activity. This study provides a simple and rapid technique for building high-performance, low-cost, and industrially available electrodes for the efficient alkaline HER.
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INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2025
·Vol. 26
·期 4
·1558
·
IF 4.9
Jiabin Huang,Haotian Wu,Ranran Gao,Lan Wu,Mengyue Wang,Yang Chu,Yuhua Shi,Li Xiang,Qinggang Yin
L-ascorbic acid (vitamin C, AA) is widely present in plants, but humans lack the ability to synthesize it independently. As a potent reducing agent, AA is susceptible to oxidation, making the enhancement of its stability crucial. 2-O-β-D-glucopyranosyl-L-ascorbic acid (AA-2βG) is a stable natural derivative of AA with glycosylation, initially discovered in the fruits ofLycium barbarum. Understanding the biosynthesis of AA-2βG is crucial for enhancing its production inL. barbarum. While the established biosynthesis pathway of AA constitutes the upstream of AA-2βG biosynthesis, the conclusive step of β-glycosylation remains unclear. We identified aL. barbarumcultivar by UPLC, ZN01, with a high content of AA-2βG, and compared its leaves, immature fruits, and mature fruits to a normal AA-2βG contentL. barbarumcultivar for metabolomic and transcriptomic analysis. The RNA-seq and RT-qPCR analysis revealed that the expression levels of genes involved in the AA biosynthesis pathway did not consistently correlate with AA-2βG content, suggesting that the final glycosylation step may be a key determinant of AA-2βG accumulation. Subsequently, utilizing phylogenetic and co-expression analysis, we identified ten UDP-glycosyltransferases (UGTs) and three β-glucosidases (BGLUs) which may be involved in the crucial step of the conversion from AA to AA-2βG, and the UGTs’ activities were predicted through molecular docking. Lastly, we speculated that the presence of the glycosylation process of AA might have a crucial role in maintaining AA homeostasis inL. barbarum, and deliberated on potential correlations between AA, carotenoids, and anthocyanins. Our integrated multi-omics analysis provides valuable insights into AA-2βG biosynthesis inL. barbarum, identifying thirteen candidate genes and highlighting the complex interplay between AA, carotenoids, and anthocyanins. These findings have implications for improving AA-2βG content inL. barbarum.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xiaolong Sun,Jiahuan Hu,Yufeng Zhou,Xiangyu Zi,Huayue Zhu,Xi Luo,Yongqian Fu
In this study, we endeavored to catalyze the biosynthesis of D -phenyllactic (D-PLA) from L-Phenylalanine (L-Phe) through a one-pot method. However, the crucial enzymes for the biosynthesis of phenylpyruvate (PPA), amino acid oxidase (L-AAD), is a membrane-bound protein. Herein, we proposed a novel co-immobilization strategy of whole cells and enzymes, integrating them into ZIF-90 to achieve efficient biosynthesis of D-PLA. Consequently, we embarked on integrating both enzyme and E. coli into ZIF-90, ultimately obtaining the novel biocatalyst E. coli /LDH@ZIF-90. This achievement facilitated the cascade reaction between LDH and E. coli , enabling a streamlined one-pot bioconversion process. The morphology and structure of E. coli /LDH@ZIF-90 were thoroughly characterized using a range of methods, including XRD, SEM, FT-IR, CLSM, and XPS, which confirmed that the material had been successfully synthesized. Further activity experiments revealed that E. coli /LDH@ZIF-90 exhibited good stability even under harsh conditions. Additionally, the biocatalyst retained 76 % of its initial catalytic activity after completing six cycles. Moreover, when utilized for the biosynthesis of D-PLA, this system demonstrated an impressive conversion rate of 85.2 % after 12 h. The successful cascade catalysis from L-Phe to D-PLA underscored the potential of the enzyme-cell cascade catalytic system, offering valuable insights for its potential industrial applications.
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Frontiers in Bioengineering and Biotechnology
·
2024
·
IF 4.3
Lei Han,Chaoqian Zhao,Yufang Zhu,Huang Li
Introduction: Bone tissue engineering is considered the ideal approach for bone repair. Mesoporous bioactive glass (MBG) possesses the characteristics of high drug-loading capacity and bioactivity. Low-intensity pulsed ultrasound contributes to promoting fracture healing and bone defect repair, and dimethyloxalyl glycine (DMOG) is a small molecular inhibitor that can suppress prolyl hydroxylase, reducing the degradation of hypoxia-inducible factor. Methods: In this study, we proposed to prepare DMOG-loaded MBG/poly(D,L-lactide) composite scaffolds (DMOG-MBG/PDLLA) for promoting bone repair. The effects of ultrasound stimulation and DMOG release on the cell responses of rat bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) and bone repair in vivo were investigated. Results and Discussion: The results showed that both ultrasound stimulation and DMOG release could promote the proliferation, adhesion and differentiation of BMSCs and HUVECs, respectively. After the implantation of scaffolds in rat cranial bone defect model for 8 weeks, the results indicated that the combined ultrasound stimulation and DMOG release contributed to the highest ability for promoting bone repair. Hence, the DMOG-MBG/PDLLA scaffolds with ultrasound stimulation are promising for application in bone repair.
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JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2024
·
IF 3.1
Wenchan Deng,Rongrong Huang,Yuanjiang Pan,Cuirong Sun
The metabolism process of amino acids is closely related to the growth of normal and cancer cells. It is still not clear how L/D-configuration amino acids participate in the metabolism of colorectal cell. Herein, intra- and extra-cellular metabolic distribution of L/D-amino acids in colorectal cell (HCT116) and human normal intestinal epithelial cell (NCM460) were profiled utilizing HPLC-MS/MS coupled with a chiral probe. The results displayed the differential metabolic portrayal for the two cell lines. Compared with NCM460 cell, 13 kinds of significant differential amino acids were founded in a lower concentration within HCT116 cell, and L-Gln was even not detected for intra-cell; as for extra-cell culture medium, the HCT116 cell consumed more L-Gln, D-Phe and D-Leu, while L-Met was low ingested in HCT116 cell. L-Ala and Gly were excretion in both two cell lines, excepted L-Cit which was uptake in HCT116 and excretion in NCM460 cell. Furthermore, the dynamic changes of chiral amino acids displayed that phenylalanine, tyrosine and tryptophan biosynthesis and arginine biosynthesis is the major pathway for intra-cellular metabolites and extra-cellular metabolites, respectively. Moreover, with additional D-amino acids in culture medium, the results exhibited that high concentration of D-amino acids have no significant effect on the proliferation of NCM460 cell, but could influence the profiling of amino acids metabolites, and further affect the proliferation of HCT116 cell. This present work enhances the understanding of these differential amino acids metabolic network and depicts a dynamic process of metabolic dysregulation of HCT116 and NCM460 cell.
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APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Songlin Chen,Zhihao Shen,Shuming Wen,Guang Han,Qicheng Feng
Flotation separation of Cu–Fe sulfide minerals typically necessitate the addition of substantial quantities of lime to depress pyrite flotation. Because lime can harm the environment, there is an urgent need to develop novel environmentally friendly depressants that are non-toxic and biodegradable. In this study, we investigated an environmentally friendly pyrite depressant containing amino and carboxyl groups, namely D-arginine (DA). The effect of DA on the surface hydrophobicity of Cu–Fe sulfide minerals and thus collector adsorption was investigated by analyzing zeta potentials, adsorption capacities, and contact angles. Additionally, changes in the surface properties of the minerals induced by DA were examined using X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), and atomic force microscopy (AFM). Flotation tests revealed that 2 × 10 –4 mol/L DA reduced the flotation recovery of pyrite to 9.96 % at low alkalinity while leaving chalcopyrite recovery unchanged. The results of mineral surface analysis indicated that DA exhibited significantly stronger adsorption on the pyrite surface than on the chalcopyrite surface. Furthermore, DA effectively reduced the adsorption of the collector on the surface of pyrite, thereby weakening pyrite floatability at low alkalinity. Therefore, DA is a promising alternative depressant for the flotation separation of chalcopyrite from pyrite.
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