Frontiers in Microbiology
·
2021
·
IF 5.64
Zheng Qiuling,Meng Xiangjun,Cheng Mingyang,Li Yanfeng,Liu Yuanpeng,Chen Xuehong
Chitosanase is a significant chitosan-degrading enzyme involved in industrial applications, which forms chitooligosaccharides (COS) as reaction products that are known to have various biological activities. In this study, the gene csnS was cloned from a deep-sea bacterium Serratia sp. QD07, as well as over-expressed in Escherichia coli, which is a new chitosanase encoding gene. The recombinant strain was cultured in a 5 L fermenter, which yielded 324 U/mL chitosanases. After purification, CsnS is a cold-adapted enzyme with the highest activity at 60°C, showing 37.5% of the maximal activity at 0°C and 42.6% of the maximal activity at 10°C. It exhibited optimum activity at pH 5.8 and was stable at a pH range of 3.4–8.8. Additionally, CsnS exhibited an endo-type cleavage pattern and hydrolyzed chitosan polymers to yield disaccharides and trisaccharides as the primary reaction products. These results make CsnS a potential candidate for the industrial manufacture of COS.
研究领域:
海洋生物技术
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酶学
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生物催化
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工业微生物学
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DOI
PubMed
高影响因子
Journal of Ocean University of China
·
2022
·Vol. 21
·期 3
·782-788
·
IF 1.179
Zhang Pengpeng,Zhang Miaomiao,Dong Kaiyu,Zhang Yicong,Yang Shuang,Wang Yuanhong,Jiang Tingfu,Yu Mingming,Lv Zhihua
Chito-oligosaccharide (COS) had shown a variety of biological activities and potential biomedical implications. The present study investigated the pharmacokinetics, bioavailability, and in vitro absorption of COS with degrees of polymerization (DPs) 2–7 and explored the influence of DPs on them. From Caco-2 cell permeation studies, COS were low permeability compounds with no directional effects, suggesting a low in vivo absorption mediated by facilitation diffusion and paracellular absorption. After an intragastrical administration to rats, COS2 showed the highest systemic exposure in six oligosaccharides. The bioavailability of COS2–7 was 7.33%, 6.11%, 4.67%, 4.13%, 4.02%, 0.99%, respectively. Differences in bioavailability for each COS correlated to structural variations, with high DPs contributing to a decrease in bioavailability. In conclusion, COS could be absorbed by the intestinal tract both in vitro and in vivo . The very low oral bioavailability of COS could be due to low permeability. DPs can affect absorption and bioavailability of COS2–7. This study provided evidence for the absorption characteristics of COS2–7 to help us better understanding the pharmacological actions.
研究领域:
药理学
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生物医学科学
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药学
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DOI
高影响因子
Food Chemistry-X
·
2025
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IF 8.2
Bowen Jiao,Nanting Zhu,Decheng Bi,Lijun Yao,Yan Wu,Beiwei Zhu,Xu Xu
Fucoxanthin (FUC), a lipid-soluble carotenoid with various bioactivities, demonstrates promise as a preventive agent against inflammatory bowel disease (IBD). Nevertheless, the inherent instability and low aqueous solubility of FUC limit its application in functional food formulations and pharmaceutical applications. In this study, a FUC-loaded pickering emulsion (G-SPI-COS/FUC emulsion) with high encapsulation efficiency and small particle size was developed by using genipin-crosslinked soy protein isolate (SPI)-chitooligosaccharide (COS) nanoparticles as stabilizers. G-SPI-COS/FUC emulsion exhibited excellent stability under varying pH values, ionic strengths, and storage conditions. In vitro digestion experiments showed that G-SPI-COS/FUC emulsion controlled FUC release and enhanced its intestinal absorption and bioavailability. Furthermore, G-SPI-COS/FUC emulsion was more effective in preventing dextran sulfate sodium (DSS)-induced colitis than free FUC and FUC-loaded pickering emulsion stabilized by native SPI. These findings indicated that G-SPI-COS/FUC emulsion could serve as a promising delivery system for FUC, providing a novel approach to the prevention of IBD.
研究领域:
食品科学
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药学
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纳米技术
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生物技术
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胃肠病学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Jinxin Lan,Yao Wu,Changmei Lin,Jiazhen Chen,Ruiqi Zhu,Xiaojuan Ma,Shilin Cao
The worldwide spread of COVID-19 has put a higher requirement for personal medical protective clothing, developing protective clothing with sustained antibacterial and antiviral performance is the priority for safe and sustaining application. For this purpose, we develop a novel cellulose based material with sustained antibacterial and antiviral properties. In the proposed method, the chitosan oligosaccharide (COS) was subjected to a guanylation reaction with dicyandiamide in the presence of Scandium (III) triflate; because of the relatively lower molecular weight and water solubility of the COS, GCOS (guanylated chitosan oligosaccharide) with high substitution degree (DS) could be successfully synthetized without acid application. In this instance, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the GCOS were only 1/8 and 1/4 of that of COS. The introduction of GCOS onto the fiber endowed the fiber with extremely high antibacterial and antiviral performance, showing 100% bacteriostatic rate against Staphylococcus aureus and Escherichia coli and 99.48% virus load reduction of bacteriophage MS2. More importantly, the GCOS modified cellulosic fibers (GCOS-CFs) exhibit excellent sustained antibacterial and antiviral properties; namely, 30 washing cycles had negligible effect on the bacteriostatic rate (100%) and inhibition rate of bacteriophage MS2 (99.0%). Moreover, the paper prepared from the GCOS-CFs still exhibited prominent antibacterial and antiviral activity; inferring that the sheeting forming, press, and drying process have almost no effect on the antibacterial and antiviral performances. The insensitive of antibacterial and antiviral activity to water washing (spunlace) and heat (drying) make the GCOS-CFs a potential material applicable in the spunlaced non-woven fabric production.
研究领域:
材料科学
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生物技术
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纺织工程
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微生物学
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DOI
PubMed
高影响因子
Applied Materials Today
·
2024
·
IF 7.2
Xiuhong Huang,Liqin Zheng,Pengfei Li,Ziling Lin,Shaohong Huang,Changren Zhou
Bone defects have been a tough clinical challenge. The natural trabecular tissue reflects a balance between the minimal metabolic cost of maintenance and maximal network stability, with mitochondria being the energy suppliers for osteogenesis. Herein, a 3D printed trabecular bone-templated scaffold composed of polylactide (PLA) modified with europium (III)-organic ligands (polydopamine and chitooligosaccharide, PDA/COS@Eu) was fabricated (denoted as Tra-PLA/PDA/COS@Eu) to augment bone repair by facilitating mitochondrial function. First, the trabecular bone templated-scaffold provides superior mechanical performance and permeability in contrast to a computer aided designed (CAD) scaffold under a same volume fraction. Tra-PLA/PDA/COS@Eu scaffold up regulated PI3K/AKT/S6K/HIF-1α pathway and significantly promoted BMSCs proliferation and osteogenic differentiation. In addition, Tra-PLA/PDA/COS@Eu scaffold provided anti-inflammatory environment by promoting macrophages M2 polarization through COS, and significantly stimulated BMSCs osteogenesis with enhanced mitochondrial function and biosynthesis. Remarkably, Eu ions are the key ingredient in enhancing mitochondrial function and biosynthesis in BMSCs. Further studies showed that the above-mentioned facilitations in a rabbit bone defect model were found to be more significant with trabecular bone-templated scaffolds, as opposed to CAD scaffolds. In summary, this novel trabecular bone-templated scaffold targeting mitochondrial function has the potential to become an effective method in the treatment of large bone defects.
研究领域:
生物材料
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组织工程
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生物医学工程
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再生医学
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材料科学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY
·
2024
·
IF 2.5
Shujie Cheng,Shimin Wu,Jianqiang Lan
Polycyclic aromatic hydrocarbons (PAHs) generated from heating butter pose a potential threat to consumer health. This study involved heating butter under different conditions and analysing the changes in the content of 54 PAHs. Furthermore, we investigated the inhibitory effects of β-carotene, pure astaxanthin and astaxanthin microcapsule powder on PAH formation. Results showed that heating temperature and duration affect the formation and transformation of PAHs, with higher temperatures facilitating the synthesis of oxygenated PAHs, whereas longer heating times promote the accumulation of light PAHs. Despite an observed increase in the concentration of light PAHs following heat treatment with added antioxidants, the antioxidants significantly reduced the toxic equivalency quotients (TEQs) in butter. This study revealed the PAH production pattern during butter heating and the effectiveness of antioxidants in inhibiting their accumulation.
研究领域:
食品科学
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毒理学
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营养学
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·
IF 27.4
Wen Li,Qi-Wen Chen,Jin-Xuan Fan,Zi-Yi Han,Wen-Fang Song,Xuan Zeng,Xian-Zheng Zhang
Due to inherent differences in cellular composition and metabolic behavior with host cells, tumor-harbored bacteria can discriminatorily affect tumor immune landscape. However, the mechanisms by which intracellular bacteria affect antigen presentation process between tumor cells and antigen-presenting cells (APCs) are largely unknown. The invasion behavior of attenuated Salmonella VNP20009 (VNP) into tumor cells is investigated and an attempt is made to modulate this behavior by modifying positively charged polymers on the surface of VNP. It is found that non-toxic chitosan oligosaccharide (COS) modified VNP (VNP@COS) bolsters the formation of gap junction between tumor cells and APCs by enhancing the ability of VNP to infect tumor cells. On this basis, a bacterial biohybrid is designed to promote in situ antigen cross-presentation through intracellular bacteria induced gap junction. This bacterial biohybrid also enhances the expression of major histocompatibility complex class I molecules on the surface of tumor cells through the incorporation of Mdivi-1 coupled with VNP@COS. This strategic integration serves to heighten the immunogenic exposure of tumor antigens; while, preserving the cytotoxic potency of T cells. A strategy is proposed to precisely controlling the function and local effects of microorganisms within tumors.
研究领域:
癌症生物学
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免疫学
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生物技术
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产品关联
DOI
PubMed
高影响因子
Science Advances
·
2024
·Vol. 10
·期 46
·
IF 11.7
Wenshang Guo,Ye Tao,Ruizhe Yang,Kaihao Mao,Hongwei Zhou,Minghui Xu,Tie Sun,Xiao Li,Changrui Shi,Zhenyou Ge,Rui Xue,Haizhou Zhou,Yukun Ren
Developing instant detection systems with disease diagnostic capabilities holds immense importance for remote or resource-limited areas. However, the task of creating these systems—which are simultaneously easy to operate, rapid in detection, and cost-effective—remains a challenge. In this study, we present a compact highly sensitive photothermal reverse transcriptase–loop-mediated isothermal amplification (RT-LAMP) chip (SPRC) designed for the detection of multiple diseases. The nucleic acid (NA) amplification on the chip is achieved through LAMP driven by either LED illumination or simple sunlight focusing. SPRC performs sample addition and amplification within a limited volume and autonomous enrichment of NA during the sample addition process, achieving a limit of detection (LOD) as low as 0.2 copies per microliter. Through 120 clinical samples, we achieved an accuracy of 95%, with a specificity exceeding 97.5%. Overall, SPRC has achieved promising progress in the application of point-of-care testing (POCT) by using light energy to simultaneously detect multiple diseases.
研究领域:
分子生物学
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医学检验
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生物医学工程
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Zhimin Deng,Hua Liu,Gantao Chen,Hongbing Deng,Xiangyang Dong,Linlin Wang,Fenghua Tao,Fangfang Dai,Yanxiang Cheng
Ovarian cancer , the deadliest gynecological malignancy, primarily treated with chemotherapy. However, systemic chemotherapy often leads to severe toxic side effects and chemoresistance. Drug-loaded aerogels have emerged as a promising method for drug delivery, as they can improve drug solubility and bioavailability, control drug release, and reduce drug distribution in non-targeted tissues, thereby minimizing side effects. In this research, chitosan oligosaccharide (COS)-loaded nanofibers composite chitosan (CS) aerogels (COS-NFs/CS) with a porous network structure were created using nanofiber recombination and freeze-drying techniques. The core layer of the aerogel has a COS loading rate of 60 %, enabling the COS-NFs/CS aerogel to significantly inhibit the migration and proliferation of ovarian cancer cells (resulting in a decrease in the survival rate of ovarian cancer cells to 33.70 % after 48 h). The coaxial fiber's unique shell-core structure and the aerogel's porous network structure enable the COS-NFs/CS aerogels to release COS steadily and slowly over 30 days, effectively reducing the initial burst release of COS. Additionally, the COS-NFs/CS aerogels exhibit good biocompatibility , degradability (only retaining 18.52 % of their weight after 6 weeks of implantation), and promote angiogenesis, thus promoting wound healing post-oophorectomy. In conclusion, COS-NFs/CS aerogels show great potential for application in the treatment of ovarian cancer.
研究领域:
癌症治疗
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生物材料科学
·
药物递送系统
·
生物医学工程
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Nanqi Zhao,Chaofan Guo,Ziyao Liu,Lin Chen,Yayun Hu,Minyi Han,Feng Huang,Zhuangli Kang,Xianchao Feng
This study investigated the effect of different hydrocolloids on the improvement of the printability and post-processing stability of minced chicken meat, each hydrocolloid was prepared with 1 % formulation and compared with the control. The effects of these hydrocolloids on the rheological properties of chicken mince and complex model printing capability were explored separately, while the cooking loss and microstructure changes of the samples before and after heating were analyzed. The results showed that the chicken mince gel containing carrageenan was more suitable for printing, increased the yield stress and apparent viscosity of the samples, and the printing process was easier to mold. In addition, carrageenan increased the hardness of the samples, and the microstructures were compact and changed little during the heating process, and the water was locked in the gel matrix, reducing shape changes during the heating process. The use of hydrocolloids improves the stability of post-processing of chicken 3D printing.
研究领域:
食品科学
·
生物材料学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Bio Materials
·
2024
·
IF 4.6
Zhaoxin Xia,Yulong Liao,Ge Gao,Shiyong Zhang
The poor accumulation of antibiotics in the cytoplasm leads to the poor eradication of intracellular bacteria. Herein, a polyelectrolyte complex (PECs@Rif) allowing direct cytosolic delivery of rifampicin (Rif) was developed for the treatment of intracellular infections by complexation of poly(α-lipoic acid) (pLA) and oligosaccharide (COS) in water and loading Rif. Due to the thiol-mediated cellular uptake, PECs@Rif delivered 3.9 times higher Rif into the cytoplasm than that of the free Rif during 8 h of incubation. After entering cells, PECs@Rif released Rif by dissociating pLA into dihydrolipoic acid (DHLA) in the presence of intracellular thioredoxin reductase (TrxR). Notably, DHLA could reduce endogenous Fe(III) to Fe(II) and provide a catalyst for the Fenton reaction to produce a large amount of reactive oxygen species (ROS), which would assist Rif in eradicating intracellular bacteria. In vitro assay showed that PECs@Rif reduced almost 2.8 orders of magnitude of intracellular bacteria, much higher than 0.7 orders of magnitude of free Rif. The bacteremia-bearing mouse models showed that PECs@Rif reduced bacterial levels in the liver, spleen, and kidney by 2.2, 3.7, and 2.3 orders of magnitude, respectively, much higher than free Rif in corresponding tissues. The direct cytosolic delivery in a thiol-mediated manner and enhanced oxidative stress proposed a feasible strategy for treating intracellular bacteria infection.
研究领域:
药学
·
生物医学工程
·
微生物学
·
药理学
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产品关联
DOI
PubMed
高影响因子
Foods
·
2024
·Vol. 13
·期 7
·1109
·
IF 4.7
Zilin Wang,Ye Zhao,Min Yang,Yuanli Wang,Yue Wang,Chongying Shi,Tianyi Dai,Yifan Wang,Liang Tao,Yang Tian
Finding stable and bioavailable calcium supplements is crucial for addressing calcium deficiency. In this study, glycated peptide–calcium chelates (WMPHs–COS–Ca) were prepared from walnut meal protein hydrolysates (WMPHs) and chitosan oligosaccharides (COSs) through the Maillard reaction, and the structural properties and stability of the WMPHs–COS–Ca were characterized. The results showed that WMPHs and COSs exhibited high binding affinities, with a glycation degree of 64.82%. After glycation, Asp, Lys, and Arg decreased by 2.07%, 0.46%, and 1.06%, respectively, which indicated that these three amino acids are involved in the Maillard reaction. In addition, compared with the WMPHs, the emulsifying ability and emulsion stability of the WMPHs–COS increased by 10.16 mg2/g and 52.73 min, respectively, suggesting that WMPHs–COS have better processing characteristics. After chelation with calcium ions, the calcium chelation rate of peptides with molecular weights less than 1 kDa was the highest (64.88%), and the optimized preparation conditions were 5:1w/wfor WMPH–COS/CaCl2s, with a temperature of 50 °C, a chelation time of 50 min, and a pH of 7.0. Scanning electron microscopy showed that the “bridging role” of WMPHs-COS changed to a loose structure. UV–vis spectroscopy and Fourier transform infrared spectrometry results indicated that the amino nitrogen atoms, carboxyl oxygen atoms, and carbon oxygen atoms in WMPHs-COS chelated with calcium ions, forming WMPHs-COS-Ca. Moreover, WMPHs-COS-Ca was relatively stable at high temperatures and under acidic and alkaline environmental and digestion conditions in the gastrointestinal tract, indicating that WMPHs–COS–Ca have a greater degree of bioavailability.
研究领域:
食品科学
·
营养学
·
化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）