JOURNAL OF CHROMATOGRAPHY A
·
2014
·
IF 4.258
Qianying Sheng,Xindai Su,Xiuling Li,Yanxiong Ke,Xinmiao Liang
A-saccharide-based stationary phase for hydrophilic interaction liquid chromatography (HILIC) is presented. The method uses carbonyl di-imidazole (CDI) as a cross-linker for dextran in aqueous solution. Different from the traditional immobilized saccharide stationary phase, this method was using a simple way to bond the high molecular of polysaccharide immobilized on the silica gel. The new method avoided the time-consuming process but had a very considerable loading result. With silica-based surface bonded, it will be possible to develop well-defined surface modifications that promote the hydrophilic with dextran and high mechanical strength with silica. For all tested compounds, including polar compounds and carbohydrates, this dextran-bonded stationary phase performed well in terms of separation efficiency and column stability, and the retention mechanism matched that of typical HILIC retention. Moreover, good selectivity was achieved in the separation of oligosaccharides and glycopeptides.
研究领域:
分析化学
·
色谱学
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产品关联
DOI
PubMed
高影响因子
SYNTHESIS-STUTTGART
·
2021
·Vol. 53
·期 14
·2435-2448
·
IF 3.157
Xin Zhou,Qing Long,Dongwei Li,Jingru Gao,Qikai Sun,Shaozi Sun,Yong Su,Peng Wang,Wenjie Peng,Ming Li
Structurally defined and pure oligosaccharides corresponding to β-glucans have attracted great attention because of their potential properties as immunostimulating agents and as antigens of vaccine candidates. We herein describe a convergent synthesis of ready-to-conjugate tridecasaccharides composed of a β-1,3-glucan nonasaccharide backbone and a β-1,6-glucan tetrasaccharide branch. The assembly was achieved by employing trichloroacetimidate glycosylations and features the gram-scale preparation of the nonasaccharide backbone and installation of the tetrasaccharide branch involving orthoester rearrangement to the glycoside.
研究领域:
有机化学
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生物化学
·
疫苗研究
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DOI
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Peiqian Zhang,Mimi Chen,Yuhao Duan,Renliang Huang,Rongxin Su,Wei Qi,Wim Thielemans,Zhimin He
Effective regulation of cellulase adsorption is key to improving the efficiencies of the two major bottlenecks of lignocellulose hydrolysis and cellulase recovery. In this work, we investigated the effect of inhibitors, pH, and temperature on the adsorption of exo- and endoglucanases (Cel7A and Cel7B, respectively) on cellulose using quartz crystal microgravimetry with dissipation. The addition of glucose and cellobiose can both inhibit the hydrolysis activity of Cel7A, whereas only cellobiose can inhibit that of Cel7B. Notably, the adsorption was favored by acidic conditions (pH ≤ 4.8) and low temperature, whereas alkaline conditions (pH 9 and 10) facilitated enzyme desorption, which is useful to guide the process of cellulase recovery. The adsorption and hydrolysis activity of Cel7A and Cel7B were both higher at 45 °C than at 25 °C. These findings pave the way to effective regulation of cellulase adsorption and thus improve lignocellulose conversion and cellulase recovery.
研究领域:
生物化学
·
可再生能源
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产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2021
·
IF 9.147
Yu-Xiao Wang,Ting Zhang,Jun-Yi Yin,Xiao-Jun Huang,Jun-Qiao Wang,Jie-Lun Hu,Shao-Ping Nie
A homogeneous β-glucan (JHMP-70) was obtained from Hypsizygus marmoreus by alkali extraction and ethanol precipitation, and had an apparent molecular weight of 394 kDa. Its fine structure was investigated by FT-IR, methylation combined with GC-MS and 1D and 2D NMR analysis. Results indicated JHMP-70 was a branched β-(1 → 6)-glucan substituted at O -3 by the non-reducing β-Glc p and/or β-(1 → 3)-linked β-Glc p side chains at a ratio of 1:1. SEM observation revealed that there were micro-spherical shapes intertwined with randomly distributed fibrous filaments. Rheological measurements showed that its flow behavior was highly dependent on the concentration. Newtonian behavior was evident at low concentration, whereas pseudoplastic behavior was observed at high concentration. Besides, the addition of salt ions (Na + or Ca 2+ ) significantly decreased the apparent viscosity of JHMP-70 solution. The low viscosity of JHMP-70 was probably attributed to its structural features, including main chain structure, branching degree and side chain length. This work can provide a basis theory to expand the application of the polysaccharides from H. marmoreus in food industry, because their lower viscosity and superior fluidity are desired in beverage products to impart stability against phase separation without compromising other sensorial properties.
研究领域:
食品科学
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生物化学
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产品关联
DOI
高影响因子
Microbiology Spectrum
·
2021
·Vol. 9
·期 3
·
IF 7.171
Alia Rizvi Syeda Kazim,Yuting Jiang,Shengnan Li,Xiaoxiao He
α-Glucan is a major cell wall component and a virulence and adhesion factor for fungal cells. However, the biosynthetic pathway of α-glucan was still unclear. α-Glucan was shown to be composed mainly of 1,3-glycosidically linked glucose, with trace amounts of 1,4-glycosidically linked glucose. Besides the α-glucan synthetases, amylase-like proteins were also important for α-glucan synthesis. In our previous work, we showed that Aspergillus nidulans AmyG was an intracellular protein and was crucial for the proper formation of α-glucan. In the present study, we expressed and purified AmyG in an Escherichia coli system. Enzymatic characterization found that AmyG mainly functioned as an α-amylase that degraded starch into maltose. AmyG also showed weak glucanotransferase activity. Most intriguingly, supplementation with maltose in shaken liquid medium could restore the α-glucan content and the phenotypic defect of a ΔamyG strain. These data suggested that AmyG functions mainly as an intracellular α-amylase to provide maltose during α-glucan synthesis in A. nidulans.IMPORTANCE Short α-1,4-glucan was suggested as the primer structure for α-glucan synthesis. However, the exact structure and its source remain elusive. AmyG was essential to promote α-glucan synthesis and had a major impact on the structure of α-glucan in the cell wall. Data presented here revealed that AmyG belongs to the GH13_5 family and showed strong amylase function, digesting starch into maltose. Supplementation with maltose efficiently rescued the phenotypic defect and α-glucan deficiency in an ΔamyG strain but not in an ΔagsB strain. These results provide the first piece of evidence for the primer structure of α-glucan in fungal cells, although it might be specific to A. nidulans.
研究领域:
微生物学
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分子生物学
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真菌遗传学
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细胞壁生物学
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Cuige Zhang,Suhan Yang,Ye Zhu,Rongli Zhang,Xiaoya Liu
The self-assembly of amphiphilic copolymers has attracted much attention because of their various morphologies and potential applications. Bowl-shaped nanoparticles could apply in many aspects due to their interior cavity, specific concave structure and high surface area. In this study, dextran (Dex) was hydrophobic modified by cinnamic acid (CINN) via esterification reaction between the hydroxyl group of Dex and the carboxyl group of CINN. The modification degree of CINN could be achieved by changing the feed ratios between Dex, CINN and the coupling agent. The cinnamic acid-modified dextran (Dex–CINN) composed of Dex as hydrophilic segment and CINN as hydrophobic segment could self-assemble into bowl-shaped nanoparticles with a single dimple on the surface. Furthermore, the size of the dimples could be controlled by changing the modification degree of CINN, concentration of Dex–CINN and the rate of water addition. The morphologies of bowl-shaped nanoparticles were characterized by transmission electron microscopy (TEM) and scanning electron microscope (SEM).
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
Advanced Materials Technologies
·
2022
·Vol. 7
·期 7
·2101382
·
IF 8.856
Lilong Cao,Zhijie Zhao,Xueying Wang,Xueli Huang,Junjie Li,Yuping Wei
Forming natural polymers-based hydrogels with enhanced mechanical strength, outstanding antifreezing property and superior conductivity is still a challenge. Here, gelatin/oxidized dextran hydrogel is fabricated and it shows enhanced mechanical performance, antifreeze tolerance, and conductivity due to the synergistic interaction of ammonium sulfate and betaine. The resulting gelatin/oxidized dextran/(NH 4 ) 2 SO 4 /betaine hydrogel exhibits high stretchability (570%), tough tensile (2.49 MPa) and compressive (46.41 MPa) fracture strength, favorable tensile (6.05 MJ m −3 ) and compressive (3.08 MJ m −3 ) toughness, antifreezing property (−30 °C) and high conductivity (2.86 S m −1 ). Based on the above characteristics, the hydrogel is applied for strain sensor to monitor the joints motion of human body such as finger, wrist, elbow, knee, neck, and throat. The hydrogel can maintain good mechanical performance and stable sensing signal from 25 to −30 °C. Therefore, the designed hydrogel based on natural polymers shows a huge potential for tissue engineering and biosensing under the mild or extreme environment.
研究领域:
材料科学
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生物医学工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Marine Drugs
·
2023
·Vol. 21
·期 3
·148
·
IF 5.4
Haiqiong Ma,Qingxia Yuan,Hao Tang,Hongjie Tan,Tingting Li,Shiying Wei,Jinwen Huang,Yue Yao,Yaping Hu,Shengping Zhong,Yonghong Liu,Chenghai Gao,Longyan Zhao
Echinoderms have been attracting increasing attention for their polysaccharides, with unique chemical structure and enormous potential for preparing drugs to treat diseases. In this study, a glucan (TPG) was obtained from the brittle starTrichaster palmiferus. Its structure was elucidated by physicochemical analysis and by analyzing its low-molecular-weight products as degraded by mild acid hydrolysis. The TPG sulfate (TPGS) was prepared, and its anticoagulant activity was investigated for potential development of anticoagulants. Results showed that TPG consisted of a consecutive α1,4–linked D-glucopyranose (D-Glcp) backbone together with a α1,4–linked D-Glcpdisaccharide side chain linked through C-1 to C-6 of the main chain. The TPGS was successfully prepared with a degree of sulfation of 1.57. Anticoagulant activity results showed that TPGS significantly prolonged activated partial thromboplastin time, thrombin time, and prothrombin time. Furthermore, TPGS obviously inhibited intrinsic tenase, with an EC50value of 77.15 ng/mL, which was comparable with that of low-molecular-weight heparin (LMWH) (69.82 ng/mL). TPGS showed no AT-dependent anti-FIIa and anti-FXa activities. These results suggest that the sulfate group and sulfated disaccharide side chains play a crucial role in the anticoagulant activity of TPGS. These findings may provide some information for the development and utilization of brittle star resources.Keywords:brittle star;polysaccharide;glucan;structure;anticoagulant activity
研究领域:
海洋生物学
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药学
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生物化学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Zuyu He,Yunhao Liu,Hui Wang,Puwang Li,Yu Chen,Chao Wang,Chuang Zhou,Shuhui Song,Shaohua Chen,Guocong Huang,Ziming Yang
Quercetin (QCT) has antioxidant, anti-inflammatory, anti-tumor and other important pharmacological activities, but the poor water solubility limits its application. In this work, the amphiphilic dextran (ADEX) was prepared by grafting L-cysteine and octadecylamine onto carboxymethyl dextran with the grafting rate of 21.29 % and 19.35 %. Then, the QCT-loaded nanomicelles (QNMs) were prepared by using ADEX as wall material and the QCT as core material via ultrasonic self-assembly method. The particle size and zeta potential of QNMs were 372 nm and 31.4 mV. Under simulated gastric and simulated intestinal fluids, the cumulative release QNMs were 37.54 % and 52.13 % within 180 min, and the QNMs showed better stability in simulated gastric fluid. The QNMs showed significantly better PTIO , OH and O 2 − scavenging activities than QCT. In addition, QNMs could effectively down-regulate the expression of pro-inflammatory cytokines and promoted the expression of anti-inflammatory cytokine. The cellular uptake results proved that the QNMs were more easily absorbed by cells than free QCT, indicating that the nano-encapsulation procedure effectively improved the uptake efficiency of QCT by cells.
研究领域:
药学
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纳米技术
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2016
·Vol. 182
·期 1
·261-275
·
IF 1.606
Jiang Cheng,Song Jinzhu,Cong Hua,Zhang Junzheng,Yang Qian
A novel β-1,3-glucanase gene, designated Ccglu17A , was cloned from the biological control fungus Chaetomium cupreum Ame. Its 1626-bp open reading frame encoded 541 amino acids. The corresponding amino acid sequence showed highest identity (67 %) with a glycoside hydrolase family 17 β-1,3-glucanase from Chaetomium globosum . The recombinant protein Ccglu17A was successfully expressed in Pichia pastoris , and the enzyme was purified to homogeneity with 10.1-fold purification and 47.8 % recovery yield. The protein’s molecular mass was approximately 65 kDa, and its maximum activity appeared at pH 5.0 and temperature 45 °C. Heavy metal ions Fe 2+ , Mn 2+ , Cu 2+ , Co 2+ , Ag + , and Hg 2+ had inhibitory effects on Ccglu17A, but Ba 2+ promoted the enzyme’s activity. Ccglu17A exhibited high substrate specificity, almost exclusively catalyzing β-1,3-glycosidic bond cleavage in various polysaccharoses to liberate glucose. The enzyme had a Km of 2.84 mg/mL and Vmax of 10.7 μmol glucose/min/mg protein for laminarin degradation under optimal conditions. Ccglu17A was an exoglucanase with transglycosylation activity based on its hydrolytic properties. It showed potential antifungal activity with a degradative effect on cell walls and inhibitory action against the germination of pathogenic fungus. In conclusion, Ccglu17A is the first functional exo-1,3-β-glucanase to be identified from C. cupreum and has potential applicability in industry and agriculture.
研究领域:
微生物学
·
酶学
·
分子生物学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2019
·
IF 6.044
Laifeng Lu,Lifeng Ji,Ruixi Shi,Shuhua Li,Xi Zhang,Qingbin Guo,Changlu Wang,Liping Qiao
Alpha-1,3-glucan is often synthesized on the surface of pathogenic filamentous fungi cell walls to block pathogen-associated molecular patterns (PAMPs) generation by host plant enzymes and the subsequent immune system response of the plant. Here, Botrytis cinerea susceptibility was assessed in tomato fruit to determine whether the fruit could recognize this camouflage and mount an immune response to it. The results showed that local mechanical wounds treated with dextran and laminarin, except amylopectin, could locally and then systemically activate disease resistance against B. cinerea infection in tomato fruit. Dextran treatment effectively elicited fruit callose deposition and phenylpropanoid and flavonoid biosynthesis to a greater extent than α-glucanase activity relative to the mock group surface wounds. Enzymatic hydrolysis of this polysaccharide provided some help in improving host disease resistance. Taken together, these results demonstrate that tomato fruit can perceive α-1,3-glucan as a kind of PAMPs but have limited ability to degrade it.
研究领域:
植物病理学
·
植物生理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Jingjing Dong,Yanli Wang,Xiaoxiao Li,Ying Chen,Rui Fan,Nana Wang,Zhengyu Jin,Yuxiang Bai
The starch-converting GH70 α-glucanotransferases, as the influential enzymatic tools for the synthesis of structurally diverse α-glucans, are of great value in the food industry. In this work, a new GtfB-type α-glucanotransferase from Fructilactobacillus sanfranciscensis Gs2 (FsGs2 GtfB) was mined from the NCBI database, which is highly conserved in four conserved regions I-IV for GtfB enzymes but possessed distinct characteristics in some residues at acceptor subsites +1/+2. Biochemical characterizations revealed that the FsGs2 GtfB enzyme demonstrated a novel 4,6-α-glucanotransferase activity, which was able to cleave the (α1 → 4) linkages in maltooligosaccharide/starch substrates and mainly synthesize branching (α1 → 4,6) linkages in the gelatinized system, resulting in the generation of low-molecular-mass short-clustered (α1 → 4,6)-glucans. Nevertheless, FsGs2 GtfB acted as a quasi-hydrolase instead of transglucosylase in the granular system, causing a notable decrease in the molecular mass of granular wheat starch and a tendency towards shortened chain lengths. Hence, the FsGs2 GtfB enzyme represents an additional potent enzymatic tool of reassembling the (α1 → 4) and (α1 → 6) linkages in starch molecules and enriches the diversity of α-glucans that can be synthesized.
研究领域:
食品科学
·
生物化学
·
酶工程
✓ 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）