Carbohydrate Research最新文献

英文中文

The preparation and evaluation of granulated chitosan-catechin tablets with excellent disintegration properties 制备和评估崩解性能优异的壳聚糖儿茶素颗粒片剂。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-08 DOI: 10.1016/j.carres.2024.109308

Tomoki Adachi , Yuto Tomita , Yasuyuki Mizukai , Yuji Maezaki , Kazuo Kawano , Kindness L. Commey , Hideaki Nakamura , Keishi Yamasaki , Masaki Otagiri , Makoto Anraku

In this study, we prepared granulated chitosan (G-CS)/catechin tablets with excellent disintegration properties. We then compared their physical properties, dissolution behavior, and pharmacokinetic profile to non-granulated chitosan (N-CS)/catechin tablets. During the tableting process, the G-CS/catechin tablets demonstrated significantly higher compatibility and superior manufacturability, as evidenced by lower ejection and detachment stress than the N-CS/catechin tablets. This resulted in more robust tablets with better physical properties. The dissolution of catechin from the G-CS/catechin tablets occurred significantly faster than from the N-CS/catechin tablets, resulting in a significantly higher 2,2′-azino-bis(3 ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity. Similarly, the primary catechin components of the tablets, epigallocatechin gallate (EGCG) and caffeine, showed faster dissolution and membrane uptake from the G-CS/catechin tablets. These indicate a more efficient tablet formulation than N-CS/catechin tablets. Furthermore, the absorption and bioavailability of EGCG and caffeine in rats were significantly higher after oral administration of the G-CS/catechin tablets than the N-CS/catechin tablets. These findings suggest that G-CS/catechin tablets, having better disintegration properties than N-CS/catechin tablets, could allow for combination with other supplements, leading to the design of highly efficient supplement combination tablets.

在这项研究中，我们制备了崩解性能极佳的粒化壳聚糖（G-CS）/儿茶素片剂。然后，我们将其物理性质、溶出行为和药代动力学特征与非粒化壳聚糖（N-CS）/儿茶素片进行了比较。在压片过程中，G-CS/儿茶素片剂的相容性和可制造性明显优于N-CS/儿茶素片剂，这表现在弹射和脱落应力低于N-CS/儿茶素片剂。这使得片剂更坚固，物理性能更好。G-CS/ 儿茶素片剂中儿茶素的溶解速度明显快于 N-CS/ 儿茶素片剂，因此其 2,2'-偶氮-双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）自由基清除能力明显更高。同样，片剂中的儿茶素主要成分表没食子儿茶素没食子酸酯（EGCG）和咖啡因在 G-CS/catechin 片剂中的溶解和膜吸收速度也更快。这表明 G-CS/catechin 片剂比 N-CS/catechin 片剂更有效。此外，大鼠口服 G-CS/儿茶素片剂后，对 EGCG 和咖啡因的吸收率和生物利用率明显高于 N-CS/儿茶素片剂。这些研究结果表明，G-CS/儿茶素片剂比 N-CS/儿茶素片剂具有更好的崩解特性，可以与其他营养补充剂结合使用，从而设计出高效的营养补充剂复合片剂。

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引用次数: 0

Capsular polysaccharide structure of Acinetobacter baumannii K58 from clinical isolate MRSN31468 从临床分离物 MRSN31468 中提取的鲍曼不动杆菌 K58 的胶囊多糖结构。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-06 DOI: 10.1016/j.carres.2024.109307

Wei Zou , Evguenii Vinogradov , Frank St-Michael , Dean Williams , Lillian Zou , Jenny Peters , Melanie Arbour , Greg Harris , Wangxue Chen , Danielle Peters

Capsular polysaccharides (CPS) of Acinetobacter baumannii is a virulence factor with diverse structures. CPS are produced by the CPS biosynthesis gene cluster in their K locus (KL). However, CPS variations may occur due to insertion of additional genes from external sources, e.g., prophages. Recently, the CPS structure from a clinical isolate, BAL062 which includes KL58 locus, was found to have a pseudaminic acid isomer (8ePse5NAc7NAc) as a result of prophage inserted epaA/epaB genes. Here, we report a CPS structure produced by A. baumannii strain MRSN31468 which also belongs to a KL58 type. The K58 CPS structure was determined by 1D and 2D NMR analysis of the oligosaccharides derived from the CPS by a phage depolymerase, and supported by the sugar composition analysis. The K58 CPS structure has the following tetra saccharide repeating unit.

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The K58 CPS differs from the CPS from BAL062 only by replacing 8-epimerized β-8ePse5NAc7NAc with β-Pse5NAc7NAc.

鲍曼不动杆菌的胶囊多糖（CPS）是一种具有多种结构的毒力因子。CPS 由其 K 基因座（KL）中的 CPS 生物合成基因簇产生。然而，由于插入了额外的外部基因（如噬菌体），CPS 可能会发生变异。最近，人们发现临床分离株 BAL062 的 CPS 结构（包括 KL58 基因座）中有一个伪氨基酸异构体（8ePse5NAc7NAc），这是噬菌体插入 epaA/epaB 基因的结果。在此，我们报告了鲍曼不动杆菌 MRSN31468 菌株产生的一种 CPS 结构，它也属于 KL58 型。K58 CPS结构是通过对噬菌体解聚酶从CPS中提取的寡糖进行一维和二维核磁共振分析确定的，并得到了糖成分分析的支持。K58 CPS 结构具有以下四糖重复单元。K58 CPS 与 BAL062 的 CPS 的不同之处仅在于用 β-Pse5NAc7NAc 取代了 8-epimerized β-8ePse5NAc7NAc。

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引用次数: 0

Preparation of N-(2-hydroxypropyltrimonium chloride)-O-dodecylylpyridine chitosan quaternary ammonium salt and its antibacterial activities N-(2-羟基丙基三甲基氯化铵)-O-十二烷基吡啶壳聚糖季铵盐的制备及其抗菌活性。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-05 DOI: 10.1016/j.carres.2024.109306

Yu Pang , Lulu Shi , Lin Wang , Tao Zhang , Meihua Xin , Mingchun Li , Yangfan Mao

Chitosan derivatives, including O-carboxymethyl chitosan (CMC), N-(2-hydroxypropyltrimonium chloride)-O-carboxymethyl chitosan (QCMC), and N-(2-hydroxypropyltrimonium chloride)-O-dodecylylpyridine chitosan quaternary ammonium salt (DQCMC), were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy, ¹H nuclear magnetic resonance (¹H NMR) spectroscopy, Ultraviolet–visible (UV–vis) spectroscopy, and element analysis (EA). The antibacterial activities of chitosan and chitosan derivatives against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were evaluated through the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antibacterial rate assays. Results demonstrated that DQCMC exhibited significantly higher antibacterial efficacy compared to chitosan, CMC, and QCMC. The MIC of DQCMC against E. coli and S. aureus were 31 μg/mL and 7 μg/mL, respectively, with a 100 % antibacterial rate at a concentration of 0.5 mg/mL. Furthermore, assessment of mouse fibroblast (L929) cell viability using cell counting kit-8 (CCK-8) methods revealed no toxicity associated with the material.

合成了壳聚糖衍生物，包括 O-羧甲基壳聚糖（CMC）、N-(2-羟基丙基三甲基氯化铵)-O-羧甲基壳聚糖（QCMC）和 N-(2-羟基丙基三甲基氯化铵)-O-十二烷基吡啶壳聚糖季铵盐（DQCMC）、合成了壳聚糖季铵盐（DQCMC），并使用傅立叶变换红外光谱（FTIR）、1H 核磁共振（1H NMR）光谱、紫外可见光谱（UV-vis）和元素分析（EA）对其进行了表征。通过最低抑菌浓度（MIC）、最低杀菌浓度（MBC）和抗菌率测定，评估了壳聚糖和壳聚糖衍生物对大肠杆菌（E. coli）和金黄色葡萄球菌（S. aureus）的抗菌活性。结果表明，与壳聚糖、CMC 和 QCMC 相比，DQCMC 的抗菌效力明显更高。DQCMC 对大肠杆菌和金黄色葡萄球菌的 MIC 分别为 31 μg/mL 和 7 μg/mL，浓度为 0.5 mg/mL 时的抗菌率为 100%。此外，使用细胞计数试剂盒-8（CCK-8）方法对小鼠成纤维细胞（L929）的存活率进行评估后发现，该材料没有毒性。

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引用次数: 0

Photocatalyst-free light-promoted carbohydrate synthesis and modification 无光催化剂光促进碳水化合物合成和改性。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-05 DOI: 10.1016/j.carres.2024.109304

Jing Wang , Fan Zhou , Yuping Xu , Lei Zhang

Photoredox catalysis has recently emerged as a powerful approach for preparing oligosaccharides because it uses mild conditions, is compatible with partially or completely unprotected carbohydrate substrates, and exhibits impressive regio‐ and stereo‐selectivity and high functional group tolerance. However, most catalytic photoredox reactions require an external photocatalyst (organic dye or expensive transition-metal complex) to deliver key glycosyl radicals. Several photocatalyst-free photocatalytic reactions that avoid the use of expensive metal salts or organic-dye additives have received significant attention. In this review, we highlight the most recent developments in photocatalyst-free light-promoted carbohydrate synthesis and modification, which is expected to inspire broad interest in further innovations in the green synthesis of saccharides.

光氧化催化最近已成为制备低聚糖的一种强有力的方法，因为它使用的条件温和，与部分或完全未受保护的碳水化合物底物兼容，并具有令人印象深刻的区域和立体选择性以及高官能团耐受性。然而，大多数催化光氧化反应都需要外部光催化剂（有机染料或昂贵的过渡金属复合物）来提供关键的糖基自由基。一些避免使用昂贵金属盐或有机染料添加剂的无光催化剂光催化反应受到了广泛关注。在这篇综述中，我们重点介绍了无光催化剂光促进碳水化合物合成和改性的最新进展，预计这将激发人们对糖类绿色合成进一步创新的广泛兴趣。

引用次数: 0

Entropy-enthalpy compensation in the methyl 5-thio-α-d-galactopyranoside–Jacalin interaction 5-thio-α-d-galactopyranoside-Jacalin 与甲基 5-thio-α-d-galactopyranoside 的相互作用中的熵焓补偿。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-05 DOI: 10.1016/j.carres.2024.109305

Daniil Ahiadorme , David Crich

Methyl 5-thio-α-d-galactopyranoside was synthesized and found to have a more favorable enthalpy of binding to Jacalin than methyl α-d-galactopyranoside, which is attributed to the greater magnitude of sulfur-π over oxygen-π interactions. This increase in enthalpy, however, was offset by a less favorable entropy of binding, arising from the need to constrain the more flexible thiosugar, thereby highlighting the complexities inherent in the design of effective sugar mimetics.

合成了甲基 5-硫代-α-d-吡喃半乳糖苷，并发现它与贾卡林的结合焓比甲基 α-d-吡喃半乳糖苷更有利，这归因于硫-π 比氧-π 相互作用更大。然而，由于需要限制更灵活的硫糖，这种焓的增加被较低的结合熵所抵消，从而突出了设计有效糖模拟物固有的复杂性。

引用次数: 0

Structure analysis and immunomodulatory activity of novel oligosaccharide from Nicotiana tabacum roots 来自烟草根的新型寡糖的结构分析和免疫调节活性。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-01 DOI: 10.1016/j.carres.2024.109303

Ming Ma , Fengdie Yan , Jing Jing , Kunyan Chen , Peng Wang , Changguo Wang , Qianfeng Chen

A novel oligosaccharide (NTRP60-W-2) with an average molecular weight of 1377 Da was isolated and purified from Nicotiana tabacum roots. Its structural characteristics and immunomodulatory properties were investigated. Structural analysis revealed that NTRP60-W-2 was composed exclusively of glucose, featuring →1)-α-D-Glcp-(6→ backbone. Immunological assays demonstrated that NTRP60-W-2 significantly enhanced cell viability, nitric oxide production and cytokine secretion (IL-6 and TNF-α) in RAW264.7 cells. These findings provide a foundation for further exploration of Nicotiana tabacum carbohydrates and their potential biological activities.

从烟草根中分离纯化了一种新型寡糖（NTRP60-W-2），其平均分子量为 1377 Da。研究了其结构特征和免疫调节特性。结构分析表明，NTRP60-W-2完全由葡萄糖组成，具有→1)-α-D-Glcp-(6→骨架。免疫学试验表明，NTRP60-W-2 能显著提高 RAW264.7 细胞的存活率、一氧化氮产量和细胞因子分泌（IL-6 和 TNF-α）。这些发现为进一步探索烟草碳水化合物及其潜在的生物活性奠定了基础。

引用次数: 0

Synthetic strategy for polyhydroxylated indolizidine iminosugar from sugar-derived HWE precursor 从糖源 HWE 前体合成多羟基吲嗪亚氨基糖的策略

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-01 DOI: 10.1016/j.carres.2024.109302

Nagaraja Ingaladal , Ravi S. Lankalapalli

The diversity of polyhydroxylated indolizidine (PI) iminosugars is ever-expanding due to the wide range of methods developed and substrate choice during synthesis. This study used an HWE precursor derived from d-glucose to extend the chain length at the C1 position. A double reductive amination and dihydroxylation of the resulting olefin, followed by intramolecular cyclization, enabled the successful synthesis of a new PI. In addition, the precursor intermediate for Mitsunobu reaction was utilized in synthesis of a new iminononulol.

由于合成方法和底物选择的广泛性，多羟基吲哚嗪（PI）亚氨基糖的多样性不断扩大。本研究使用一种源自 d-葡萄糖的 HWE 前体来延长 C1 位置的链长。对得到的烯烃进行双还原胺化和二羟基化，然后进行分子内环化，成功合成了一种新的 PI。此外，还利用 Mitsunobu 反应的前体中间体合成了一种新的亚氨基壬基酚。

引用次数: 0

Effect of bacterial dissociation on lipopolysaccharide structure: A study of O-polysaccharide from the marine bacterium Pseudoalteromonas agarivorans KMM 232 (O-form) 细菌解离对脂多糖结构的影响：对海洋细菌 Pseudoalteromonas agarivorans KMM 232（O-form）O 型多糖的研究。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-01 DOI: 10.1016/j.carres.2024.109300

Maxim S. Kokoulin , Vlada S. Belova , Lyudmila A. Romanenko

The lipopolysaccharide (LPS) was obtained from a bacterium Pseudoalteromonas agarivorans KMM 232 (O-form) isolated from a seawater sample collected at a depth of 500 m. The O-polysaccharide (OPS) was isolated by mild acid degradation of the LPS and studied by chemical methods along with 1D and 2D ¹H and ¹³C NMR spectroscopy, including ¹H,¹H COSY, ¹H,¹H TOCSY, ¹H,¹H ROESY and ¹H,¹³C HSQC, and ¹H,¹³C HMBC experiments. The following new structure of the OPS from P. agarivorans KMM 232 (O-form) containing 2-acetamido-2-deoxy-d-glucose (D-GlcNAc), d-glucose (D-Glc), d-glucuronic acid (D-GlcA), 4,6-O-[(R)-1-carboxyethylidene]-d-galactose [D-Galp4,6 (R-Pyr)] and two residues of d-galactose (D-Gal) was established:

脂多糖（LPS）取自从 500 米深处采集的海水样本中分离出的一种假交替单胞菌（Pseudoalteromonas agarivorans KMM 232）（O-form）。通过弱酸降解 LPS 分离出了 O 型多糖（OPS），并通过化学方法以及一维和二维 1H 和 13C NMR 光谱（包括 1H,1H COSY、1H,1H TOCSY、1H,1H ROESY 和 1H,13C HSQC 以及 1H,13C HMBC 实验）对其进行了研究。以下是来自 P. agarivorans KMM 232（O-form）的 OPS 的新结构，其中含有 2-乙酰氨基-2-脱氧-d-葡萄糖（D-GlcNAc）、d-葡萄糖（D-Glc）、d-葡萄糖醛酸（D-GlcA）、4,6-O-[(R)-1-羧基亚乙基]-d-半乳糖[D-Galp4,6 (R-Pyr)]和两个 d-半乳糖残基（D-Gal）。

引用次数: 0

Sustainable production of organic acids from chitin biomass catalyzed by Keggin-type heteropolyacid under hydrothermal condition 水热条件下 Keggin 型杂多酸催化甲壳素生物质可持续生产有机酸。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-01 DOI: 10.1016/j.carres.2024.109299

Yulong Chang, Yongtai Wang, Yimo Feng, Xiangling Zhu, Hongjun Zang

The “shell biorefinery,” which valorizes the shell waste chitin into fine chemicals, has developed rapidly in recent years. Herein, we present a novel base-free heteropolyacid-catalyzed oxidation method for the transformation of chitin biomass into organic acid. After a series of optimization experiments, a 5.93 % yield of formic acid and 25.09 % yield of acetic acid were achieved in the presence of 0.5 equivalent of Mo–V–P heteropolyacids (H₄PMo₁₁VO₄₀·2H₂O) and air at 180 °C under hydrothermal conditions for 4 h. Meanwhile, we have demonstrated that the Keggin-type heteropolyacid catalysts are capable of efficiently converting microcrystalline chitin into organic acids. The synthesized heteropolyacids are well characterized with FT-IR, XRD, ICP-AES, and TGA. The possible reaction pathway was speculated accordingly. This method offers several advantages, including readily available raw materials, simple operation, and relatively higher yield.

近年来，将贝壳废弃物甲壳素转化为精细化学品的 "贝壳生物炼制 "技术发展迅速。在此，我们提出了一种将甲壳素生物质转化为有机酸的新型无碱杂多酸催化氧化法。经过一系列优化实验，在 180 ℃ 水热条件下，在 0.5 当量的 Mo-V-P 杂多酸（H4PMo11VO40-2H2O）和空气存在下反应 4 小时，甲酸收率为 5.93%，乙酸收率为 25.09%。同时，我们还证明了凯金型杂多酸催化剂能够高效地将微晶甲壳素转化为有机酸。我们利用 FT-IR、XRD、ICP-AES 和 TGA 对合成的杂多酸进行了表征。据此推测了可能的反应途径。该方法具有原料易得、操作简单、产率较高等优点。

引用次数: 0

Modeling conformational changes in alginic acid oligomers induced by external forces 模拟藻酸低聚物在外力作用下的构象变化。

IF 2.4 3区化学 Q3 BIOCHEMISTRY & MOLECULAR BIOLOGY

Carbohydrate Research

Pub Date : 2024-11-01 DOI: 10.1016/j.carres.2024.109294

Agnieszka Brzyska , Wojciech Płaziński

In this study, the mechanism and nature of mechanical force-induced conformational transitions of alginate oligomers with different ratios of β-d-mannuronic acid (M unit) and α-l-guluronic acid (G unit) units were investigated. The influence of the type of glycosidic linkage in either homo- or heterooligomers on the nature of conformational transitions was also considered. For this purpose, two different theoretical methods were used: quantum mechanics (QM) at the DFT level with the EGO (Enforced Geometry Optimization) approach previously tested also for other saccharide systems, and molecular dynamics (MD) simulations within hybrid interaction potentials, which take into account both the ab initio (QM) level of theory and classical molecular mechanics (MM) force fields. This allowed to characterize in detail the structural and energetic properties of the conformational transition occurring upon the influence of external, mechanical forces (e.g. ring conformations at the path of ring-inversion process as well as the energies corresponding to initial, final and intermediate states). The results indicate qualitatively various responses against the applied force, depending on the G:M ratio, which have their source in differing topologies of glycosidic linkage in either G or M units. This is of potential relevance for determining the content of naturally heterogeneous alginate chains by the AFM experimental studies. The effects of explicit solvent and non-zero temperature are not of primarily importance in the context of determined stretching properties.

本研究探讨了不同比例的β-d-甘露糖酸（M单位）和α-l-谷朊酸（G单位）单位的海藻酸低聚物的机械力诱导构象转变的机制和性质。研究还考虑了同源或异源低聚物中糖苷键的类型对构象转变性质的影响。为此，研究人员采用了两种不同的理论方法：DFT 水平的量子力学（QM）和 EGO（强制几何优化）方法，前者曾在其他糖类系统中进行过测试；后者是在混合相互作用势中进行的分子动力学（MD）模拟，其中考虑到了 ab initio（QM）理论水平和经典分子力学（MM）力场。这样就能详细描述在外部机械力影响下发生的构象转变的结构和能量特性（例如，环形反转过程路径上的环形构象，以及与初始、最终和中间状态相对应的能量）。研究结果表明，G:M 比率不同，对外力的反应也不同，其根源在于 G 或 M 单元中糖苷键的拓扑结构不同。这对于通过原子力显微镜实验研究确定天然异构藻酸盐链的含量具有潜在意义。显性溶剂和非零温度的影响对于确定拉伸特性并不重要。

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