Journal of Macromolecular Science Part B-Physics
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2018
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IF 1.005
Yun Yang,Wenjuan Liu,Jianjun Fang,Yunhui Zhao,Yanmin Zhao,Tianlong Huang,Jiale Cui,Wei Wu,Xiaofei Li,Zhihua Zhou
Random terpolymers of poly(L-lactide-glycolide-ε-caprolactone) (PLLGC) was prepared by ring-opening polymerization of L-lactide, glycolide and ε-caprolactone monomers initiated with stannous octanoate. Fourier transform infrared spectra, nuclear magnetic resonance and gel permeation chromatography were employed to characterize the obtained PLLGC terpolymers. The effects of polymerization temperature, reaction time, the amount of initiator and the polymerization pressure on the weight average molecular mass and polydispersity index of the PLLGC were investigated. In addition, the water contact angle of the PLLGC was also tested. The characterization of chemical structure showed that the PLLGC was successfully synthesized. For instance, a PLLGC terpolymer with a weight average molecular mass of about 12.435 × 104 Da and a polydispersity index of 1.28 was obtained when the polymerization was conducted with a molar ratio of monomer to initiator ([M]/[I]) of 2000, polymerization temperature of 140 °C, polymerization pressure of 5.0 Pa and reaction time of 24 h. The random incorporation of ε-CL monomer units decreased the wettability of the PLGA copolymers.
研究领域:
高分子化学
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生物医学材料
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高分子合成与表征
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NATURAL PRODUCT RESEARCH
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2026
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IF 1.6
Di Zhang,Yujiang Dai,Xin Wang,Qi Mai,Lu Jiang,Tuanjie Wang,Huifang Li,Xing Ren,Rongbin Wei
The halophyte Suaeda maritima subsp. salsa (L.) Soó has been utilised as a traditional medicinal herb in China. Its phytochemical profile remains inadequately elucidated to date. In this study, twelve compounds, including one previously undescribed biflavonoid, 3′-methoxy-4′,4′″,5,5″-tetrahydroxy-[C7-O-C7″]-biflavone (1), and eleven known compounds (2∼12), were isolated from the whole plant of S. salsa. Their structures were fully determined via NMR, MS data analysis and literature comparison. The anti-microbial assay revealed that compounds 1, 9, and 12 exhibited an inhibitory effect against P. aeruginosa with an MIC of 25 μg/mL. Additionally, compounds 3, 5, 7, 9 and 12 displayed potent inhibitory activity against the growth of E. coli, with their MIC values ranging from 12.5 to 25 μg/mL. Furthermore, compound 1 showed the cytotoxic activity against human SGC-7901 cells with an IC50 of 89.04 ± 0.26 μm. Biflavonoid 1 represents the first reported occurrence of this class of compounds within the genus Suaeda.
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POWDER TECHNOLOGY
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2026
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IF 5.5
Jinqiu Fu,Zheng Ren,Huanfa Feng,Jingliang Xu,Wei Zhuang,Hanjie Ying,Pengpeng Yang,Keke Zhang
Solvent effects on L-carnosine spherical aggregates were studied. • Reduced (001) solvent-crystal interaction promotes spherulitic growth. • Tip defects trigger non-crystallographic branching and spherulitic growth. • The spherulitic crystals exhibited superior flow properties. L-carnosine, a biologically active dipeptide with significant antioxidant properties, typically crystallizes in a needle-like habits that result in poor flowability and low bulk density, posing significant challenges for downstream processing. This study provides a new strategy for the preparation and optimization of spherical L-carnosine crystals. Systematic solvent screening identified dimethyl sulfoxide (DMSO) as the optimal antisolvent, enabling the formation of dense, uniform spherulites. The effects of main crystallization parameter on the morphology and properties of the spherical crystals were explored and the optimal crystallization conditions were determined. Molecular dynamics simulations and experimental analyses reveal that DMSO selectively reduces the solvent-crystal interaction energy on the (001) crystal face, accelerating growth at the crystal tips and triggering non-crystallographic branching. Compared to the raw material and spherical agglomerates, the spherulites show a 3.6-fold and 2.7-fold increase in bulk density, respectively. More importantly, they exhibit excellent flowability (Carr's index 14.4% vs. 47.8% and 39.2%; Hausner's ratio 1.16 vs. 1.92 and 1.47), highlighting the primary advantage of the spherulitic growth strategy. This work provides a mechanistic understanding of spherulitic growth and offers a practical route to enhance the powder properties of L-carnosine. Download: Download high-res image (223KB) Download: Download full-size image Solvent‑dependent morphology evolution and non‑crystallographic branching mechanism in L‑carnosine spherulitic crystallization.
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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2026
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IF 6.7
Cheng Chen,Yamin Huang,Juan Li,Meijuan Xu,Hui Li,Guoqiang Xu,Jinsong Shi,Zhenghong Xu,Xiaomei Zhang
l-Tryptophan, an essential amino acid, serves as a critical precursor for the biosynthesis of numerous bioactive compounds. In this study, we engineered tryptophan synthase (TrpS) to develop an efficient cell factory for l-tryptophan production. Initially, EcTrpS from Escherichia coli K-12 was expressed in E. coli BL21 (DE3) to construct strain BS, which produced 836.43 mg/L of l-tryptophan. To alleviate substrate inhibition, we constructed a mutant library of 104–105 variants through two rounds of error-prone PCR and utilized a biosensor employing a green fluorescent protein to report l-serine consumption for screening TrpS mutants. Mutant C10 showed a 375% increase in enzyme activity compared with strain BS. Computational analysis was used to explore an improved catalytic mechanism. Finally, through systematic process optimization and catalytic strategy, strain C10 produced 94.2 g/L of l-tryptophan, the highest titer via whole-cell transformation. This study provides new perspectives and strategies for TrpS engineering and the industrial production of l-tryptophan.
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MOLECULAR BIOLOGY REPORTS
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2026
·Vol. 53
·期 1
·1291
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IF 3.2
Zhu Mo-li,Hao Rui,Zhao Meng-yao,Liu Pei-yao,Zhang Hong-dou,Li Peng,Yin Ya-ling,Liu Hui-jun,Ren Guang-qiu,Zhang Jie,Yang Jing
Background The clinical use of doxorubicin (DOX), a widely used and effective antitumor drug, is limited by its cardiotoxicity. Currently, safe and effective strategies for preventing doxorubicin-induced cardiotoxicity (DIC) remain limited. Therefore, this study aimed to investigate the potential cardioprotective effects and possible underlying mechanisms of L-arginine (L-Arg) against DIC. Methods and Results To investigate the cardioprotective effects and underlying mechanisms of L-Arg, three complementary experimental models were used: male Sprague–Dawley rats ( n = 6 per group), male AMPKα2 knockout (AMPKα2 KO) mice ( n = 6 per group), and H9c2 cardiomyocytes. A DIC model was induced in rats by intraperitoneal injection of DOX (2.5 mg/kg/week) for 6 weeks. Serum nitric oxide (NO) and lactate dehydrogenase (LDH) levels were measured to assess oxidative stress and myocardial injury. Cardiac morphology, inflammation, and fibrosis were evaluated by histological staining and protein expression analyses, whereas miR-29b-3p expression was determined by RT-qPCR. AMPKα2-deficient models and miR-29b-3p gain- and loss-of-function models were used to investigate the underlying mechanisms. Compared with the DOX group, L-Arg significantly improved cardiac function and morphology, reduced oxidative stress, myocardial injury, inflammation, and fibrosis, and increased miR-29b-3p expression (all P < 0.05). Moreover, miR-29b-3p overexpression enhanced, whereas miR-29b-3p inhibition attenuated, the cardioprotective effects of L-Arg ( all P < 0.05 ). These protective effects were also markedly attenuated by AMPKα2 deficiency ( P < 0.05 ). Conclusions L-Arg alleviates DIC by improving cardiac function, reducing oxidative stress, inflammation, and fibrosis, and increasing miR-29b-3p expression. These cardioprotective effects are associated with AMPKα2 activation and enhanced miR-29b-3p expression.
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MICROCHIMICA ACTA
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2026
·Vol. 193
·期 10
·685
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IF 5.4
Qin Ziyao,Jia Menggai,Zhan Yue,Yang Molin,Hu Beibei,Li Zhiwei,Sun Shiguo
L -Glutamate ( L -Glu), a major excitatory neurotransmitter in the central nervous system, plays an important role in nitrogen metabolism. In this study, chiral mesoporous imprinted silica nanoparticles (CMISNs) were synthesized via the sol-gel method using L -Glu derivatives as templates. Subsequently, the AuNPs/CMISNs@CMK-3/GCE electrochemical sensing interface was constructed. Benefiting from the chiral mesoporous structure of CMISNs and combined high conductivity of CMK-3 and signal amplification effect of gold nanoparticles (AuNPs), the designed electrochemical sensor enables specific detection of L -Glu. The developed sensor exhibits a wide linear response range for L -Glu (1 nM to 1 mM), with a limit of detection of 0.15 nM and a limit of quantification of 0.52 nM. It also demonstrated remarkable enantioselectivity, achieving a chiral separation factor of 7.7 toward glutamate enantiomers, along with good reproducibility (RSD = 3.2%, n = 5). The sensor retained excellent stability over 14 days and high selectivity against potential interferents. In contrast to conventional enzyme-based biosensors, chiral recognition is achieved by imprinted mesopores of L -Glu without the involvement of biological enzymes. This work provides a novel bionic sensing platform for the precise detection of L -Glu, which holds significant potential in neuroscience research and clinical diagnosis. Graphical abstract
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INORGANIC CHEMISTRY
·
2025
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IF 4.7
Yong Wang,Zhiyong Bai,Shanshan Chen,Xu Chen,Liangmeng Zhu,Tao Ouyang,Yanqiang Li,Weiqi Huang,Yipeng Song,Sangen Zhao,Junhua Luo
Ultraviolet (UV) nonlinear optical (NLO) crystals capable of expanding common laser sources to the UV regime are core components of solid-state lasers. Currently, exploring UV NLO crystals in hybrid organic–inorganic systems is receiving increasing attention. Herein, we report the synthesis, characterization, and linear and NLO properties of a semiorganic UV NLO crystal, namely, lithium l-aspartate monohydrate, Li(L-OOCNH3CHCH2COO)·H2O (1). The title compound crystallizes in the noncentrosymmetric polar monoclinic space group P21. It exhibits layered structures composed of [LiO4] tetrahedra, l-aspartate, and isolated H2O molecules; the layers are further strengthened by robust interlayer N–H···O hydrogen bonding to form the whole architectures. Optical measurements revealed that compound 1 exhibits a phase-matchable second-harmonic generation (SHG) response with powder efficiency 0.9 times that of KDP, a short UV transmission cutoff edge at 208 nm, and wide optical bandgap of 5.42 eV. Frist-principles calculations were conducted to elucidate the origin of the underlying linear and NLO properties.
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Chemical and Biological Technologies in Agriculture
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2025
·Vol. 12
·期 1
·1-18
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IF 5.2
Xie Wenli,Xia Qing,Xu Zongchang,Xu Kuo,Fu Xianjun
Apocynum venetum L. represents a species with medicinal-food homology that is utilized in the management of hypertension and is widely consumed as a health-promoting tea in East Asia. This study reports the identification and characterization of two novel polysaccharides (PSs), AV1-N1 and AV2-N1, extracted from A. venetum L. The PSs were purified with a DEAE Seplife FF an ion exchange column and a Sephacryl S-400HR gel column and characterized by monosaccharide composition, FT-IR spectroscopy, methylation, and NMR spectroscopic analyses. It was determined that AV1-N1 and AV2-N1 were primarily composed of arabinose and galactose in varying proportions, with average molecular weights of 64.1 kDa and 58.8 kDa, respectively. The primary structure of both AV1-N1 and AV2-N1 predominantly comprises the R → 6)-β- D -Gal p (1 → R) unit, featuring α-L-Ara f (1 → R) branches at the C-3 position. Both AV1-N1 and AV2-N1 possess a reducing end characterized by the R → 3,6)-β- D -Gal p (1 → R) unit and share identical nonreducing ends, specifically the R → 5)-α-L-Ara f (1 → R) residue. In addition, this study provides the first comprehensive evaluation of the cardioprotective activities of A. venetum L. PSs, demonstrating significant protective effects against DOX-induced heart failure. Notably, at identical concentrations, AV2-N1 demonstrates more pronounced therapeutic efficacy than AV1-N1 across evaluation indicators including pericardial edema area, heart rate, ejection fraction, and cardiac output. It is postulated that AV2-N1 may enhance ampk , pgc-1α , nrf2 , gpx4a , ho-1 , and prdx1 gene expression, thereby effectively inhibiting reactive oxygen species (ROS) production and mitigating oxidative damage, ultimately exerting cardioprotective effects. These findings hold significant promise for the further development and utilization of A. venetum L. PSs. Graphical
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Materials Today Communications
·
2022
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IF 3.662
Bo Li,Moyuan Qu,Haocheng Yang,Yue Shu,Wenqian Xiao,Songsong Zhu,Xiaoling Liao
Simulating the hierarchical structure of natural bone, mineralized synthetic polymer fibrils such as poly(L-lactic acid) (PLLA) in the form of microspheres show considerable potential as injectable scaffolds for bone defect repair. However, the hydrophobicity of PLLA restricts the deposition of bone-like apatite on the surface of PLLA directly, limiting its application in osteogenesis. In this paper, after sodium trimetaphosphate (STMP) modification, nanofibrous PLLA microspheres were immersed into 2.5 times simulated body fluid (2.5 ×SBF) for 3 days to produce abundant bone-like apatite on the surface of microspheres. The bioactivity in vitro and bone repair ability in vivo of surface mineralized PLLA microspheres were evaluated. The results indicated that surface mineralized nanofibrous PLLA microspheres improved MSCs proliferation and bone-related gene expression, including OPN, RUNX-2 and OCN. After the surface mineralized nanofibrous PLLA microspheres were implanted into rat skulls to repair bone defects (5 mm) for 6 weeks, the micro-CT and histology results showed that the surface mineralized nanofibrous PLLA microspheres improved bone regeneration compared to pure nanofibrous PLLA microspheres. Our study provides a feasible strategy for the rapid preparation of biomimetic mineralized PLLA scaffolds, the novel mineralized microspheres showed considerable bone repair potential.
研究领域:
生物材料学
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组织工程学
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医学
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Natural Products and Bioprospecting
·
2025
·Vol. 15
·期 1
·1-13
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IF 4.9
Zang Hao-Jing,Bai Xiao-Lin,Sui Xue-Yi,Zhai Xiao-Rui,Wang Yong-Cui,Xin Zhong-Quan,Yin Qiu-Yuan,Hao Xiao-Jiang,Wang Yue-Hu,Liao Xun,Di Ying-Tong
Parkinson’s disease (PD), the second most common neurodegenerative disorder globally, arises from selective dopaminergic neuron degeneration. While current therapies address symptoms, disease-modifying agents remain an unmet need. Herein, we investigated Nicotiana tabacum L. (Solanaceae), a plant linked epidemiologically to reduced PD risk, as a source of multi-target neuroprotective compounds. From ultra-low nicotine (< 0.04%) tobacco leaves, we isolated 22 molecules, including a novel 21-norsesterterpenoid (Nicotiazanorpenoid A) and eight previously unreported compounds. Systematic evaluation revealed three synergistic neuroprotective mechanisms: (1) Antioxidant activity: Scopoletin ( 3 ) and isoferulic acid ( 6 ) showed significant radical scavenging capacity (ABTS assay; IC 50 = 27.74, and 18.13 μM, respectively); (2) Neuronal protection: cis -11,14,17-Eicosatrienoic acid methyl ester ( 14 ) enhanced survival (93.94% vs. control) in 6-OHDA-induced PC12 cells, surpassing rasagiline (88.36% at equivalent concentrations); (3) MAO-B inhibition: five compounds displayed selective inhibition, with scopoletin ( 3 ) exhibiting highest potency ( K i = 20.7 μM). Notably, plant prostaglandins ( 10/11 ) were identified as competitive MAO-B inhibitors first time through molecular docking and 100-ns MD simulations, revealing stable binding at the FAD site (ΔG = − 10.42, and − 9.75 kcal/mol, respectively). Graphical
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CRYOBIOLOGY
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2024
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IF 2.3
Xin Li,Yukun Cao,Chenxi Liu,Jia Tan,Xinli Zhou
Cryopreservation of biological samples is an important technology for expanding their applications in the biomedical field. However, the quality and functionality of samples after rewarming are limited by the toxicity of commonly used cryoprotectant agents (CPAs). Here, we developed a novel preservation system by combining the natural amino acid l -proline (L-Pro) with gelatin methacryloyl (GelMA) hydrogels. Compared with dimethyl sulfoxide (DMSO), L-Pro and GelMA demonstrated excellent biocompatibility when co-culturing with cells. Cryopreservation procedures were optimized using 3T3 as model cells. The results showed that rapid cooling was the most suitable cooling procedure for L-Pro and GelMA among the three cooling procedures. Co-culturing with cells for 3 h before cryopreservation, 6 % L-Pro +7 % GelMA had the highest survival rate, reaching up to 80 %. Differential Scanning Calorimetry (DSC) analysis showed that 6 % L-Pro + 7 % GelMA lowered the freezing point of the solution to −4.2 °C and increased the unfrozen water content to 20 %. To the best of our knowledge, this is the first report of cell cryopreservation using a combination of L-Pro and GelMA hydrogels, which provides a new strategy for improving cell cryopreservation.
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INTERNATIONAL JOURNAL OF CHEMICAL KINETICS
·
2014
·Vol. 46
·期 3
·169-175
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IF 1.566
Hong-Ya Li,Xiao-Li Zhang,Jie-Bing Zhang,Tian-Tian Zhang,Bin-Xia Zhao
The transesterification of phosphatidylcholine with methanol was successfully carried out using a promising solvent methyl tert-butyl ether instead of traditional ether, and the reaction was dramatically enhanced in the presence of tetrabutylammonium hydroxide as the phase-transfer catalyst. Kinetics of the reaction including the effects of the reaction conditions on the conversion of phosphatidylcholine and the apparent rate constant ( k app ) were investigated in detail. On the basis of the experimental evidence, the transesterification mechanism was proposed and a kinetic model was developed, and the experimental data were well described by the pseudo–first-order equation.
研究领域:
生物化学
·
有机化学
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危险品化学品经营许可证（带存储）