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1.
研究了化香果提取物对水产常见9种致病菌嗜水气单胞菌(Aeromonas hydrophila)、温和气单胞菌(Aeromonas sobria)、豚鼠气单胞菌(Aeromonas caviae)、维氏气单胞菌(Aeromonas veronii)、迟钝爱德华菌(Edwardsiella tarda)、副溶血弧菌(Vibrio parahaemolyticus)、鼠疫耶尔森氏菌(Yersinia pestis)、大肠杆菌(Escherichia coli)和金黄色葡萄球菌(Staphylococcus aureus)的抑菌活性。研究结果表明:化香果提取物对9种细菌均具有抑制作用,最小抑菌浓度为4.50 g/L。对每种细菌而言,抑菌效果随化香果提取物质量浓度的增加而增强,其中对大肠杆菌的抑制能力最强,IC50值为0.035 g/L;金黄色葡萄球菌次之,IC50值为0.053 g/L。对雌雄小鼠急性经口毒性试验结果表明化香果提取物对小鼠的急性经口半数致死量(LD50值)分别为5 010和7 940 mg/kg体质量,表明化香果提取物属于实际无毒级。 相似文献
2.
Nicki Frederiksen Assoc. Prof. Paul R. Hansen Dr. Dorota Zabicka Magdalena Tomczak Malgorzata Urbas Dr. Ilona Domraceva Prof. Fredrik Björkling Assoc. Prof. Henrik Franzyk 《ChemMedChem》2020,15(24):2544-2561
The influence of hydrophobicity on antibacterial activity versus the effect on the viability of mammalian cells for peptide/peptoid hybrids was examined for oligomers based on the cationic Lys-like peptoid residue combined with each of 28 hydrophobic amino acids in an alternating sequence. Their relative hydrophobicity was correlated to activity against both Gram-negative and Gram-positive species, human red blood cells, and HepG2 cells. This identified hydrophobic side chains that confer potent antibacterial activity (e. g., MICs of 2–8 μg/mL against E. coli) and low toxicity toward mammalian cells (<10 % hemolysis at 400 μg/mL and IC50>800 μg/mL for HepG2 viability). Most peptidomimetics retained activity against drug-resistant strains. These findings corroborate the hypothesis that for related peptidomimetics two hydrophobicity thresholds may be identified: i) it should exceed a certain level in order to confer antibacterial activity, and ii) there is an upper limit, beyond which cell selectivity is lost. It is envisioned that once identified for a given subclass of peptide-like antibacterials such thresholds can guide further optimisation. 相似文献
3.
Nasrin Oroujzadeh Elham Delpazir Zahra Shariatinia 《Particulate Science and Technology》2019,37(4):423-429
Using ultrasonic top-to-down method, nanoparticles of two N-nicotinyl phosphoric triamides: C5H4NC(O)NHP(O)R, R?=?4-CH3-NC5H10 (1), (CH3)3CNH2 (2) were prepared for the first time and characterized by 31P, 13C, 1H NMR, FTIR, scanning electron microscopy, energy dispersive X-ray. The average particle size of 1 and 2 were 60–70 and 40–50?nm, respectively, and the morphology was spherical for 1 and rod for 2. Solid state (powder) antibacterial effect of these compounds and two other similar reported ones, in their macro- and nanosizes, were evaluated with colony counting method on one Gram-positive (Staphylococcus aureus) and one Gram-negative (Escherichia coli) bacteria in Brain–Heart infusion culture medium. Results showed that all the macro- and nanosized compounds, except macrosized 1, were antibacterial and all nanoscaled ones had stronger antibacterial activity than their macroscaled analogues. The most effect of the particle size was observed for 1: by decreasing the particle sizes, the antibacterial activity state of 1 was changed from inactive (for macro) to potent (for nano). 相似文献
4.
Min Zhou Weinan Jiang Jiayang Xie Dr. Wenjing Zhang Zhemin Ji Jingcheng Zou Zihao Cong Ximian Xiao Jiawei Gu Prof. Runhui Liu 《ChemMedChem》2021,16(2):309-315
Poly(2-oxazoline)s have excellent biocompatibility and have been used as FDA-approved indirect food additives. The inert property of the hydrophilic poly(2-oxazoline)s suggests them as promising substitutes for poly(ethylene glycol) (PEG) in various applications such as anti-biofouling agents. It was recently reported that poly(2-oxazoline)s themselves have antimicrobial properties as synthetic mimics of host defense peptides. These studies revealed the bioactive properties of poly(2-oxazoline)s as a new class of functional peptide mimics, by mimicking host defense peptides to display potent and selective antimicrobial activities against methicillin-resistant Staphylococcus aureus both in vitro and in vivo, without concerns about antimicrobial resistance. The high structural diversity, facile synthesis, and potent and tunable antimicrobial properties underscore the great potential of poly(2-oxazoline)s as a class of novel antimicrobial agents in dealing with drug-resistant microbial infections and antimicrobial resistance. 相似文献
5.
Pierre Santucci Christina Dedaki Alexandros Athanasoulis Laura Gallorini Anaïs Munoz Dr. Stéphane Canaan Dr. Jean-François Cavalier Dr. Victoria Magrioti 《ChemMedChem》2019,14(3):349-358
In the quest for new antibacterial agents, a series of novel long- and medium-chain mono- and disubstituted β-lactones was developed. Their activity against three pathogenic mycobacteria—M. abscessus, M. marinum, and M. tuberculosis—was assessed by the resazurin microtiter assay (REMA). Among the 16 β-lactones synthesized, only 3-hexadecyloxetan-2-one (VM005) exhibited promising activity against M. abscessus, whereas most of the β-lactones showed interesting activities against M. marinum, similar to that of the classical antibiotic, isoniazid. Regarding M. tuberculosis, six compounds were found to be active against this mycobacterium, with β-lactone VM008 [trans-(Z)-3-(hexadec-7-en-1-yl)-4-propyloxetan-2-one] being the best growth inhibitor. The promising antibacterial activities of the best compounds in this series suggest that these molecules may serve as leads for the development of much more efficient antimycobacterial agents. 相似文献
6.
7.
Benhui Hu Christopher Berkey Timothy Feliciano Xiaohong Chen Zhuyun Li Chao Chen Shahrouz Amini Mui Hoon Nai Qun-Li Lei Ran Ni Juan Wang Wan Ru Leow Shaowu Pan Yong-Qiang Li Pingqiang Cai Ali Miserez Shuzhou Li Chwee Teck Lim Yun-Long Wu Teri W. Odom Reinhold H. Dauskardt Xiaodong Chen 《Advanced materials (Deerfield Beach, Fla.)》2020,32(12):1907030
Bacterial infections remain a leading threat to global health because of the misuse of antibiotics and the rise in drug-resistant pathogens. Although several strategies such as photothermal therapy and magneto-thermal therapy can suppress bacterial infections, excessive heat often damages host cells and lengthens the healing time. Here, a localized thermal managing strategy, thermal-disrupting interface induced mitigation (TRIM), is reported, to minimize intercellular cohesion loss for accurate antibacterial therapy. The TRIM dressing film is composed of alternative microscale arrangement of heat-responsive hydrogel regions and mechanical support regions, which enables the surface microtopography to have a significant effect on disrupting bacterial colonization upon infrared irradiation. The regulation of the interfacial contact to the attached skin confines the produced heat and minimizes the risk of skin damage during thermoablation. Quantitative mechanobiology studies demonstrate the TRIM dressing film with a critical dimension for surface features plays a critical role in maintaining intercellular cohesion of the epidermis during photothermal therapy. Finally, endowing wound dressing with the TRIM effect via in vivo studies in S. aureus infected mice demonstrates a promising strategy for mitigating the side effects of photothermal therapy against a wide spectrum of bacterial infections, promoting future biointerface design for antibacterial therapy. 相似文献
8.
Huan-yu Tao Qin Hu Yi Wu Peng Han Xiaobo Liang 《International Journal of Food Science & Technology》2021,56(8):3807-3813
A strain, Rahnella aquatilis L103, which was isolated from the soil around the roots of mushrooms, produced antibacterial protein though fermentation. This protein has broad antibacterial spectrum towards gram-positive and gram-negative bacteria. The protein has a significant antioxidant capacity on scavenging ABTS+· (82.5%, 120 μg mL−1), DPPH· (64.1%, 600 μg mL−1) and OH· (60.1%, 750 μg mL−1) as well. The protein was considered to be safe within concentration of 150 μg mL−1 as shown by MTT results and was applied to beef refrigerated preservation. The treatment group presented lower total viable counts (TVC), total volatile basic nitrogen (TVB-N), 2-thiobarbituric acid (TBA), meanwhile, higher sensory score and longer shelf life (2 days) compared with the control group (P < 0.05). The results indicated that the protein under safe concentration was beneficial to beef preservation. 相似文献
9.
《Ceramics International》2020,46(14):22171-22180
An effective g-C3N4/Fe@ZnO heterostructured photocatalyst was synthesized by a simple chemical co-precipitation method and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and ultraviolet–visible spectroscopy. Transmission electron microscopy revealed that 7-8 nm-sized 1%Fe@ZnO nanoparticles were evenly distributed on g-C3N4 nanosheets to form a hybrid composite. The photocatalytic effectiveness of the composites was assessed against methylene blue dye, and it was found that the 50%g-C3N4/Fe@ZnO photocatalyst was more efficient in harvesting solar energy to degrade dye than the ZnO, 1%Fe@ZnO, g-C3N4, g-C3N4/ZnO and (10, 25, 40, 60 & 75 wt%) g-C3N4/Fe@ZnO samples. The antibacterial competency of the samples was also explored against Gram-positive (Bacillus subtilis, Staphylococcus aureus and Streptococcus salivarius) and Gram-negative (Escherichia coli) bacteria through the well diffusion method. The 50%g-C3N4/Fe@ZnO nanocomposite exhibited a superior antibacterial action compared to that of the rest of the samples. The exceptionally improved photocatalytic and antimicrobial efficiency of the 50%g-C3N4/Fe@ZnO composite was primarily accredited to the synergic outcome of the interface established between Fe@ZnO nanoparticles and g-C3N4 nanosheets. 相似文献
10.
Carla Giovana Luciano Larissa Tessaro Rodrigo Vinicius Lourenço Ana Mônica Quinta Barbosa Bittante Andrezza Maria Fernandes Isabel Cristina Freitas Moraes Paulo José do Amaral Sobral 《International Journal of Food Science & Technology》2021,56(2):587-599
The addition of nisin into a gelatin matrix can change properties of the film. The aim of this work was to develop gelatin-based films containing different nisin concentrations in order to study their influence on the film's antimicrobial and physical properties and their rheological properties as a film-forming solution (FFS). The FFS was characterised by rheological assays, and the gelatin-based active films were characterised and assessed by the effects of nisin concentrations on their various properties, including antimicrobial activity. Nisin's concentration affected not only its viscoelastic properties of FFS but also its film solubility in water, film surface roughness and light barrier. The addition of nisin also slightly modified the water contact angle and the mechanical properties of the gelatin films. Finally, the films demonstrated activity against Staphylococcus aureus and Listeria monocytogenes at concentrations above 56 mg of nisin g−1 of gelatin. 相似文献