Articles de revues : « ZOI »

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Karpiński, Tomasz M., et Artur Adamczak. « Fucoxanthin—An Antibacterial Carotenoid ». Antioxidants 8, n^o 8 (24 juillet 2019) : 239. http://dx.doi.org/10.3390/antiox8080239.

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Fucoxanthin is a carotenoid produced by brown algae and diatoms. This compound has several biological properties such as antioxidant, anti-obesity, anti-diabetic, anticancer, and antimicrobial activities. Unfortunately, until now the latter effect has been poorly confirmed. The aim of this study was an evaluation of fucoxanthin activity against 20 bacterial species. Antimicrobial effect of fucoxanthin was determined by using the agar disc-diffusion and micro-dilution methods. The studied carotenoid acted against 13 bacteria growing in aerobic conditions. It was observed to have a significantly stronger impact on Gram-positive than Gram-negative bacteria. Mean zones of growth inhibition (ZOIs) for Gram-positive bacteria ranged between 9.0 and 12.2 mm, while for Gram-negative were from 7.2 to 10.2 mm. According to the agar disc-diffusion method, the highest activity of fucoxanthin was exhibited against Streptococcus agalactiae (mean ZOI 12.2 mm), Staphylococcus epidermidis (mean ZOI 11.2 mm), and Staphylococcus aureus (mean ZOI 11.0 mm), and in the microdilution test towards Streptococcus agalactiae with the minimal inhibitory concentration (MIC) of 62.5 µg/mL. On the other hand, fucoxanthin was not active against strict anaerobic bacteria.

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Et al., Hussein. « The Antibacterial, Antiheamolytic, and Antioxidant Activities of Laurus nobilis and Alhagi maurorum Native to Iraq. » Baghdad Science Journal 16, n^o 3(Suppl.) (22 septembre 2019) : 0707. http://dx.doi.org/10.21123/bsj.2019.16.3(suppl.).0707.

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Ethanolic crude extracts of leaves from Laurus nobilis and Alhagi maurorumfor were screened for alkaloids, saponins, tannins, anthraquinones, steroids, flavonoids, glycosides, and glucosides contents. Biochemical activities, including antibacterial activity, antioxidant, and antihemolytic activity, were investigated. Antibacterial activity against Three types of pathogenic bacteria was detected by disc diffusion analysis and characterized by zone of inhibition (ZOI). Antioxidant properties were determined by a diphenyl-1- picrylhydrazyl (DPPH) method. Results revealed that the inhibitory activity of the plants against G+ve and G-ve bacteria were different, where the greatest ZOI of Alhagi maurorum against Staphylococcus aureus was 12.66 mm, while its effect against Pseudomonas aeruginosa generated an 8.33 mm ZOI, with no did not effects on Escherichia coli. Extract of Laurus nobilis against Escherichia coli with a ZOI reached to 10.33 mm, but did not significantly influence the growth of Staphylococcus aureus and Pseudomonas aeruginosa. When the plant extracts were mixed in equal quantities, the percentage of the effect were increased, where the greatest effect of the mixed observed in E. coli was a 16.66mm ZOI, and in Staphylococcus aureus to 15.66mm. In Pseudomonas aeruginosa the ZOI reached to a 12.33 mm. This is referred to as synergistic effect between these plants against pathogenic bacteria. The extracts did not have any toxic effects on human red blood cells.

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Baral, Bikash, Geeta Shrestha Vaidya et Nabin Bhattarai. « Bioactivity and biochemical analysis of water hyacinth (Eichhornia crassipes) ». Botanica Orientalis : Journal of Plant Science 8 (2 mars 2012) : 33–39. http://dx.doi.org/10.3126/botor.v8i0.5556.

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Water hyacinth (Eichhornia crassipes) is an invasive aquatic weed causing serious threats to water ecosystems throughout the world. Recently, considerable attention has been given at harvesting the plant for practical uses. An experiment on the bioactivity of water hyacinth was conducted using the soxhlet extraction (hot method) and cold percolation method in chloroform and ethanol in order to evaluate the antimicrobial properties of the plant. Plant samples were also analyzed for the presence of major pharmacologically active compounds. The antimicrobial assay was performed using well diffusion method against nine different clinical bacterial strains and six phytopathogenic fungal strains. The chloroform hot extract showed activity against 22.22% (Zone of Inhibition, ZOI < 13mm) bacteria and 66.66% (ZOI < 12mm) fungi; while the cold extract showed activity against 50% (ZOI < 13mm) fungi, but no activity against bacteria. Similarly, the ethanol hot extract showed activity against 77.77% (ZOI < 19mm) bacteria and 66.66% (ZOI < 20mm) fungi, while the cold extract showed activity against 77.77% (ZOI < 10mm) bacteria and 50% (ZOI < 14mm) fungi. The ethanolic hot and cold extract proved to be far better than the chloroform fraction showing more antibacterial activity, while they share the same value and possess same effectiveness against the different fungi. Chemical analysis indicated that the major components in these extracts were saponins, polyoses, alkaloid salts, and reducing compounds. The present study showed that the devastating aquatic weed, with strong antimicrobial potentials and presence of biologically active phytochemicals, may be useful for developing alternative compounds to treat infectious diseases caused by bacterial and fungal pathogens. doi: http://dx.doi.org/10.3126/botor.v8i0.5556 Botanica Orientalis – Journal of Plant Science (2011) 8: 33-39

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Cui, Xihong, Zhenxian Quan, Xuehong Chen, Zheng Zhang, Junxiong Zhou, Xinbo Liu, Jin Chen, Xin Cao et Li Guo. « GPR-Based Automatic Identification of Root Zones of Influence Using HDBSCAN ». Remote Sensing 13, n^o 6 (23 mars 2021) : 1227. http://dx.doi.org/10.3390/rs13061227.

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The belowground root zone of influence (ZOI) is fundamental to the study of the root–root and root–soil interaction mechanisms of plants and is vital for understanding changes in plant community compositions and ecosystem processes. However, traditional root research methods have a limited capacity to measure the actual ZOIs within plant communities without destroying them in the process. This study has developed a new approach to determining the ZOIs within natural plant communities. First, ground-penetrating radar (GPR), a non-invasive near-surface geophysical tool, was used to obtain a dataset of the actual spatial distribution of the coarse root system in a shrub quadrat. Second, the root dataset was automatically clustered and analyzed using the hierarchical density-based spatial clustering of applications with noise (HDBSCAN) algorithm to determine the ZOIs of different plants. Finally, the shape, size, and other characteristics of each ZOI were extracted based on the clustering results. The proposed method was validated using GPR-obtained root data collected in two field shrub plots and one simulation on a dataset from existing literature. The results show that the shrubs within the studied community exhibited either segregated and aggregated ZOIs, and the two types of ZOIs were distinctly in terms of shape and size, demonstrating the complexity of root growth in response to changes in the surrounding environment. The ZOIs extracted based on GPR survey data were highly consistent with the actual growth pattern of shrub roots and can thus be used to reveal the spatial competition strategies of plant roots responding to changes in the soil environment and the influence of neighboring plants.

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Baniya, Amina, Sushma Singh, Minu Singh, Pragya Nepal, Mahesh Adhikari, Sagar Aryal et Anurag Adhikari. « Isolation and Screening of Antibiotics Producing Streptomyces spp from the Soil Collected around the Root of Alnus nepalensis from Godawari ». Nepal Journal of Biotechnology 6, n^o 1 (15 janvier 2019) : 46–56. http://dx.doi.org/10.3126/njb.v6i1.22337.

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Actinomycetes are considered as the most invaluable prokaryotes whose genome mining show a great number of putative secondary metabolite biosynthesis pathways as well as gene clusters ranging from 20 to 50 per genome. The genus Streptomyces has been explored for its ability to produce 60% antibiotics worldwide. Alnus nepalensis (Alder) has been found to harbor diverse Eubacteria in its rhizosphere. To evaluate the antibiotic production potential from Actinomycetes, we collected soil samples from rhizosphere (5-7 cm deep) of Alder tree. Primary screening was done by cross-streak method against Multidrug Resistant (MDR) such as Methicillin resistant Staphylococcus auereus (MRSA), Vancomycin resistant Enterococcus feacalis (VRE), Imepenem resistant Acinetobacterbaumannii, Vancomycin resistant Klebsiella pneumonia and Imepenem resistant E. coli as well as Non-MDRs (E. coli, Bacillus subtilis, Klebsiella pneumoniae, S. aeureu and Enterococcus feacalis). Extraction of antibiotics was done using rota-vapour from extract obtained by solid-substrate fermentation technique followed by solvent extraction. Secondary screening was done using well diffusion assay against MDRs. Among total of 40 isolates of Actinomycetes recovered, 14 showed remarkable zone of inhibition (ZOI) to various MDRs. NASA 303 showed 26 mm of ZOI against VRE, NASA 101 had ZOI of 34 mm against MRSA, NASA 319 had 33.7 mm ZOI against Imepenem resistant E. coli, NASA 306 had 36 mm of ZOI against Vancomycin resistant Klebsiella pneumoniae, and NASA 108 showed ZOI of 29.6 mm against Imepenem resistant E. faecalis. This investigation revealed that the Actinomycetes found in Rhizosphere of Alder tree had MDR killing potent antibiotics, which needs to be further explored.

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Shresta, Shrimita, Sudip Bhandari, Babita Aryal, Bishnu P. Marasini, Santosh Khanal, Pramod Poudel, Binod Rayamajhee, Bikash Adhikari, Bibek Raj Bhattarai et Niranjan Parajuli. « Evaluation of Phytochemical, Antioxidant and Antibacterial Activities of Selected Medicinal Plants ». Nepal Journal of Biotechnology 9, n^o 1 (31 juillet 2021) : 50–62. http://dx.doi.org/10.3126/njb.v9i1.38667.

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Medicinal plants are important reservoirs of bioactive compounds that need to be explored systematically. Because of their chemical diversity, natural products provide limitless possibilities for new drug discovery. This study aimed to investigate the biochemical properties of crude extracts from fifteen Nepalese medicinal plants. The total phenolic contents (TPC), total flavonoid contents (TFC), and antioxidant activity were evaluated through a colorimetric approach while the antibacterial activities were studied through the measurement of the zone of inhibition (ZoI) by agar well diffusion method along with minimum inhibitory concentrations (MIC) by broth dilution method. The methanolic extracts of Acacia catechu and Eupoterium adenophorum showed the highest TPC (55.21 ± 11.09 mg GAE/gm) and TFC (10.23 ± 1.07 mg QE/gm) among the studied plant extracts. Acacia catechu showed effective antioxidant properties with an IC50 value of 1.3 μg/mL, followed by extracts of Myrica esculenta, Syzygium cumini, and Mangifera indica. Morus australis exhibited antibacterial activity against Klebsiella pneumoniae (ZoI: 25mm, MIC: 0.012 mg/mL), Staphylococcus aureus ATCC 25923 (ZoI: 22 mm, MIC: 0.012 mg/mL), Pseudomonas aeruginosa (ZoI; 20 mm, MIC: 0.05 mg/mL), and methicillin-resistant Staphylococcus aureus (MRSA) (ZoI: 19 mm, MIC: 0.19 mg/mL). Morus australis extract showed a broad-spectrum antibacterial activity, followed by Eclipta prostrata, and Hypericum cordifolium. Future study is recommended to explore secondary metabolites of those medicinal plants to uncover further clinical efficacy.

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Joshi, Sunil Kumar, Deepak Kumar Semwal, Ankit Kumar et Ashutosh Chauhan. « Antimicrobial activity of the water-soluble ash extract from the invasive weed Parthenium hysterophorus L. » CURRENT MEDICAL AND DRUG RESEARCH 4, n^o 02 (25 septembre 2020) : 1–6. http://dx.doi.org/10.53517/cmdr.2581-5008.422020208.

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Parthenium hysterophorus L., also known as congress grass or carrot grass, is a widely distributed invasive weed which is a big challenge for sustainable agriculture. For the past several years, a number of attempts have been made to evaluate its medicinal properties. The present study aimed to evaluate the antimicrobial activity of the water-soluble ash extract of P. hysterophorus against different bacterial and fungal pathogens. The disc diffusion method was used to measure zone of inhibition (ZOI) whereas broth microdilution method was used to evaluate minimum inhibitory concentration (MIC) of the extract. The extract was found most effective against Staphylococcus aureus with a ZOI value of 33.5 mm at 33 mg/mL concentration when compared with ofloxacin (ZOI = 39.5 mm at 5 μg/disc). The extract was also found active against Salmonella enterica, Staphylococcus epidermidis and Escherichia coli with ZOI values of 25.5, 32.5 and 25.5 mm, respectively. The present study revealed that the ash extract of P. hysterophorus has potential to inhibit various bacterial species. However, the tested fungal pathogens like Candida albicans were found unaffected after treating with the ash extract.

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Wu, Jiawen, Yinshan Yang, Jiahai Zhang, Peng Ji, Wenjing Du, Peng Jiang, Dinghai Xie et al. « Domain-swapped Dimerization of the Second PDZ Domain of ZO2 May Provide a Structural Basis for the Polymerization of Claudins ». Journal of Biological Chemistry 282, n^o 49 (25 septembre 2007) : 35988–99. http://dx.doi.org/10.1074/jbc.m703826200.

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Zonula occludens proteins (ZOs), including ZO1/2/3, are tight junction-associated proteins. Each of them contains three PDZ domains. It has been demonstrated that ZO1 can form either homodimers or heterodimers with ZO2 or ZO3 through the second PDZ domain. However, the underlying structural basis is not well understood. In this study, the solution structure of the second PDZ domain of ZO2 (ZO2-PDZ2) was determined using NMR spectroscopy. The results revealed a novel dimerization mode for PDZ domains via three-dimensional domain swapping, which can be generalized to homodimers of ZO1-PDZ2 or ZO3-PDZ2 and heterodimers of ZO1-PDZ2/ZO2-PDZ2 or ZO1-PDZ2/ZO3-PDZ2 due to high conservation between PDZ2 domains in ZO proteins. Furthermore, GST pulldown experiments and immunoprecipitation studies demonstrated that interactions between ZO1-PDZ2 and ZO2-PDZ2 and their self-associations indeed exist both in vitro and in vivo. Chemical cross-linking and dynamic laser light scattering experiments revealed that both ZO1-PDZ2 and ZO2-PDZ2 can form oligomers in solution. This PDZ domain-mediated oligomerization of ZOs may provide a structural basis for the polymerization of claudins, namely the formation of tight junctions.

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Hu, Li Ming, Heng Zhen Lee, Jian Wang et Jian Ting Du. « Centrifuge Modeling and Numerical Simulation of Air Sparging Process ». Advanced Materials Research 378-379 (octobre 2011) : 445–48. http://dx.doi.org/10.4028/www.scientific.net/amr.378-379.445.

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Air sparging (AS) is one of the in-situ groundwater remediation techniques for remediating volatile organic compounds (VOCs) contaminated soil, and the knowledge of air flow features is essential in designing air sparging system for soil remediation. The centrifuge modeling technique was employed to simulate the in-situ conditions and to investigate air follow characteristics during air sparging by using glass beads as soils. Several centrifugal modeling tests were performed under various g-levels. According to the test results, the zone of influence (ZOI) during air sparging is in a truncated-cone shape under various g-levels, which can be expressed by the lateral expansion around the air injection point and the cone angle between the vertical axis and the boundary of ZOI. A 2D numerical model is used to model the air movement during air sparging process. The ZOI and the water saturation distribution were obtained. The results agree well with the centrifuge test data, which indicates the two phase flow model is reasonable to simulate the air sparging process. It was also shown that air compressibility and buoyant force have a significant influence on the extent of ZOI and should be adequately considered. Hence centrifuge modeling and numerical simulation can be used as a design tool for in-situ air sparging system

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Wang, Jian, et Li Ming Hu. « Numerical Simulation of Air Flow during Air Sparging Remediation ». Applied Mechanics and Materials 138-139 (novembre 2011) : 27–32. http://dx.doi.org/10.4028/www.scientific.net/amm.138-139.27.

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A 2D numerical model is used to modeling the movement of air during air sparging process for groundwater remediation. The zone of influence (ZOI) and the water saturation distribution can be obtained from the calculations. The results agree well with the centrifuge test data, indicating the two-phase flow model is reasonable for numerical simulation of air sparging process. It was also shown that air compressibility has a significant influence on the extent of ZOI.

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Adhikari, Nisha, Anita Rana, Sangita Oli, Srijana Neupane, Ravin Bhandari et Dirgha Raj Joshi. « Study of In-vitro Antioxidant and Antibacterial activity of leaf extract of Azadirachta indica, and Ocimum sanctum in different organic solvents and Cow urine ». Journal of Drug Delivery and Therapeutics 10, n^o 1-s (15 février 2020) : 90–95. http://dx.doi.org/10.22270/jddt.v10i1-s.3908.

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Background: Neem (Azadirachta indica), Tulsi (Ocimum sanctum) and Cow urine (Bos indicus) has been widely used as a therapeutic potential or additive agent in different ethnomedicinal practices as well as modern science also proved its therapeutic potential to treat various diseases and balance the body conditions. Aims: Alone study on Neem, Tulsi and Cow urine (CU) has been widely performed but this study aims to evaluate the individual as well as synergistic antioxidant and antibacterial activity of Neem, and Tulsi’s leaves extract in different organic solvents and Cow urine. Materials and Methods: Antioxidant activity was carried out by using 2,2-Diphenyl1-picrylhydrazyl (DPPH) radical scavenging activity and the antibacterial activity was tested by the agar disc diffusion method against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli, Proteus vulgaris and Klebsiella species) bacteria. Results: The antioxidant and antibacterial activity is concentration-dependent. The neem extract in chloroform shows the highest ZOI against S. aureus (14±2). Similarly, the neem extract in cow urine (8±0.86) and tulsi extract in methanol (8±1.04) shows the highest ZOI against E. coli. Against K. species cow urine is most effective (9±0.29) followed by neem extract in chloroform and cow urine (8±0.77). In P. vulgaris almost all sample shows ZOI around 7 mm. In synergistic antibacterial study tulsi and neem extract in cow urine shows the highest ZOI against E. coli (12±1.75) and P. vulgaris (10±1.44). The tulsi and neem extract in hexane is not effective against S. aureus and E. coli but effective in P. vulgaris and K. species (ZOI 7 mm). Tulsi and neem extract in chloroform, methanol, and cow urine show similar ZOI (9 mm). In DPPH free radical scavenging activity the methanolic extract of tulsi shows the highest inhibition of free radicle (96.35±0.001), followed by methanolic extract of neem (84.85±0.042). The fresh cow urine inhibits (25.19±0.037) followed by neem extract in chloroform (24.53±0.003), neem extract in cow urine (21.8±0.012), tulsi extract in chloroform (20.86±0.047), tulsi extract in hexane (19.5±0.031), tulsi extract in cow urine (18.33±0.023) and the least inhibition by neem extract in hexane (6.74±0.042).

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Khangaonkar, Tarang, Adi Nugraha et Taiping Wang. « Hydrodynamic Zone of Influence Due to a Floating Structure in a Fjordal Estuary—Hood Canal Bridge Impact Assessment ». Journal of Marine Science and Engineering 6, n^o 4 (15 octobre 2018) : 119. http://dx.doi.org/10.3390/jmse6040119.

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Floating structures such as barges and ships affect near-field hydrodynamics and create a zone of influence (ZOI). Extent of the ZOI is of particular interest due to potential obstruction to and impact on out-migrating juvenile fish. Here, we present an assessment of ZOI from Hood Canal (Floating) Bridge, located within the 110-km-long fjord-like Hood Canal sub-basin in the Salish Sea, Washington. A field data collection program allowed near-field validation of a three-dimensional hydrodynamic model of Hood Canal with the floating bridge section embedded. The results confirm that Hood Canal Bridge, with a draft of 4.6 m covering ~85% of the width of Hood Canal, obstructs the brackish outflow surface layer. This induces increased local mixing near the bridge, causes pooling of water (up-current) during ebb and flood, and results in shadow/sheltering of water (down-current). The change in ambient currents, salinity, and temperature is highest at the bridge location and reduces to background levels with distance from the bridge. The ZOI extends ~20 m below the surface and varies from 2–3 km for currents, from 2–4 km for salinity, and from 2–5 km for temperature before the deviations with the bridge drop to <10% relative to simulated background conditions without the bridge present.

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Thapa, Suchitra, Basudha Shrestha et Sarita Manandhar. « Revisiting the Revised CLSI Breakpoint for Detecting Fluoroquinolones Resistance in Salmonella ». Journal of Institute of Science and Technology 25, n^o 2 (25 décembre 2020) : 119–24. http://dx.doi.org/10.3126/jist.v25i2.33748.

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Resistance towards fluoroquinolones and treatment failure is a matter of concern in enteric fever. The present study was undertaken to analyze the susceptibility pattern of Salmonella towards fluoroquinolones using 2006 and 2013 Clinical Laboratory Standards Institute (CLSI) breakpoint for interpretation and revisit the efficacy of Nalidixic acid resistance (NAR) as a phenotypic marker. A retrospective analysis of the zone of inhibition (ZOI) diameter data and minimum inhibitory concentration (MIC) data of 105 Salmonella was conducted. The ZOI diameter analysis showed that all isolates were susceptible to Ofloxacin and Ciprofloxacin using the previous 2006 ZOI breakpoint. However, with the revised 2013 breakpoint of Ciprofloxacin, the susceptibility percent dropped significantly and for Ofloxacin the breakpoint was not revised, so the percentage remained unchanged. The MIC analysis showed that all isolates were susceptible towards Ofloxacin and 97.14 % of isolates were susceptible to Ciprofloxacin using the previous 2006 MIC breakpoint, while the susceptibility decreased for both antibiotics with the revised 2013 MIC breakpoint. Statistically, the ZOI diameter of Nalidixic acid and MIC values of Ciprofloxacin and Ofloxacin was negatively correlated. To conclude, the revision of breakpoints addresses the problem of screening fluoroquinolones resistance but the emerging fluoroquinolones resistance situation is still a matter of concern in healthcare facilities of Nepal. Thus a reliable screening method is need of the hour as NAR cannot be considered a reliable marker to screen fluoroquinolones resistance

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Michalopoulou, Zoi-Heleni. « Ask an Acoustician : Zoi-Heleni Michalopoulou ». Acoustics Today 17, n^o 1 (2021) : 62. http://dx.doi.org/10.1121/at.2021.17.1.62.

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Robinson, Andrew D., Todd A. Walroth, Leigh J. Spera, Rajiv Sood, Brett Hartman, Megan Cheatham et Ryan Relich. « 52 Developing a Topical Antibiogram in the Burn Unit ». Journal of Burn Care & ; Research 41, Supplement_1 (mars 2020) : S34—S35. http://dx.doi.org/10.1093/jbcr/iraa024.056.

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Abstract Introduction Antibiograms display susceptibilities based on bacterial growth in response to systemic agents, utilizing automated systems performing bacterial identification and susceptibility testing. There is a paucity of literature regarding burn-specific antibiograms or susceptibility testing of organisms isolated from wound cultures against topical antimicrobials. Our goal was to create an institutional topical antimicrobial antibiogram in burn and dermatologic disorder patients. Methods Institutional topical antimicrobial agent susceptibilities were retrospectively reviewed from 1/1/18-12/31/18. Quantitative biopsies or swabs collected from patients were cultured. Susceptibility plates were prepared by wells aseptically punched into an agar plate and inoculated with antimicrobial creams. Bacterial isolates were then inoculated in melted agar, overlaid onto the susceptibility dish, and incubated. Zones of inhibition (ZOI) were reported in mm; susceptible being any measurable zone and resistant defined as a zone of 0 mm. Isolated organisms were grouped as Gram-positive cocci (GPC), Gram-negative rods (GNR), or yeast-like fungi (YLF). Results In 2018, 21 organisms were tested for susceptibility in 19 patients with positive cultures. Overall susceptibilities of isolates were 71–91%. Overall, susceptibility rates were: gentamicin 71%, mupirocin 77%, silver sulfadiazine 77%, and mafenide 91%. All C. albicans isolates were susceptible to nystatin. Excluding resistant isolates, the median (IQR) ZOI measurements were: gentamicin 10.0 (7.0, 15.0), mupirocin 12.0 (7.5, 27.0), silver sulfadiazine 8.0 (7.0, 10.5), and mafenide 14.5 (10.3, 19.8). Of organisms reported, there were 10 GNR (45%), 8 GPC (36%), and 4 YLF (18%), with P. aeruginosa, MRSA, and C. albicans being most common. For GPC, susceptibility rates were 63–88% and median (IQR) ZOI measurements were: gentamicin 16.0 (8.0, 30.0), mupirocin 27.0 (9.8, 35.5), silver sulfadiazine 10.0 (8.5, 19.0), and mafenide 15.0 (10.0, 22.0). For GNR, susceptibility rates were 70–90% and median (IQR) ZOI measurements were: gentamicin 10.0 (6.0, 11.0), mupirocin 12.0 (7.0, 18.0), silver sulfadiazine 7.5 (7.0, 9.5), and mafenide 15.0 (13.0, 19.0). Conclusions Based on susceptibility profiles of isolated organisms, mafenide appears to be an appropriate first-line empiric agent with an overall susceptibility rate greater than 90% and the largest ZOI amongst topical agents tested. When examining GPC, mupirocin demonstrated the largest ZOI and may be a more appropriate empiric choice if Gram-stain results are available. Applicability of Research to Practice To our knowledge, no previously published studies exist in burn patients examining susceptibilities to topical antimicrobials. These antibiogram-level data provide direction for empiric treatment of wound infections utilizing local susceptibilities for targeted topical coverage.

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Boyd, T. J., M. T. Montgomery, R. H. Cuenca et Y. Hagimoto. « Combined radiocarbon and CO2 flux measurements used to determine in situ chlorinated solvent mineralization rate ». Environmental Science : Processes & ; Impacts 17, n^o 3 (2015) : 683–92. http://dx.doi.org/10.1039/c4em00514g.

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Pretorius, M. « A framework for turnaround practitioners to assess reasonable prospect for ventures operating in the zone of insolvency ». South African Journal of Business Management 48, n^o 4 (31 décembre 2017) : 57–70. http://dx.doi.org/10.4102/sajbm.v48i4.43.

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Turnaround practitioners (TPs) and business rescue practitioners (BRPs) are tasked with making the critical decision of whether a distressed business has reasonable prospect (RP) for reorganisation. Creditors often require the same determination because only businesses assessed to have a reasonable prospect can enter the rescue or reorganisation process. These determinations are difficult because they are made within a ‘zone of insolvency’ (ZoI). Going concerns operate on a solvent basis but may slide into the ZoI where conditions are ambiguous, unclear and uncertain. At the same, time, the specific conditions and contexts of distressed businesses vary widely despite some generic similarities that may exist. Therefore, the decision about reasonable prospect depends largely on how TP and BRPs perceive and make sense of the ambiguous conditions within the zone of insolvency. Finally, creditors and courts rarely agree with such RP determinations, but no generic tool exists to satisfy all stakeholders. Hence, the decision of whether (or not) a distressed business has a reasonable prospect to embark upon a reorganisation intervention involves both rational and subjective assessment to make sense of the conditions present in the ZoI. An affordance framework with guiding scores is proposed to determine reasonable prospect.

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Joshi, Susan, Yagya Prasad Subedi et Shobha Kumari Paudel. « Antibacterial and Antifungal Activity of Heartwood of Acacia catechu of Nepal ». Journal of Nepal Chemical Society 27 (22 août 2012) : 94–99. http://dx.doi.org/10.3126/jncs.v27i1.6667.

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Antibacterial activity of different extracts of heartwood of Acacia catechu were tested against 11 species of bacteria and antifungal activity were tested against four species of fungi. Among bacteria species highest zone of inhibition (ZOI) was measured against Pseudomonas species by diethyl ether extract, likewise among fungal organism highest zone of inhibition (ZOI) was measured against Fusarium oxysporim by ethyl acetate extract. No extracts showed activity against Salmonella typhi, Salmonella paratyphi, Escherichia coli and Proteus mirabilis. The minimum bactericidal concentration (MBC) of ethyl acetate extract was evaluated against Bacillus subtilis, Klebsiella pneumonia, Staphylococus aureus and Shigella species.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6667 J. Nepal Chem. Soc., Vol. 27, 2011 94-99

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Nur, Alma, Arif Yahya et Rio Risandiansyah. « Efek Kombinasi Fraksi Alkaloid Imperata Cylindrica L. Dengan Amoksisilin Atau Kloramfenikol Terhadap Daya Hambat Staphylococcus Aureus ». Jurnal Kesehatan Islam : Islamic Health Journal 8, n^o 2 (24 septembre 2020) : 74. http://dx.doi.org/10.33474/jki.v8i2.8887.

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Alkaloid merupakan senyawa yang terkandung dalam Imperata cylindrica L. (alang – alang). Ekstrak metanolik I. cylindrica L. diketahui berinteraksi dengan beberapa jenis antibiotik. Namun, belum ada penelitian yang membuktikan bahwa alkaloid dari I.cylindrica L. dapat meningkatkan kinerja antibiotik.Penelitian ini mengisolasi senyawa alkaloid dan melihat pengaruh penambannya terhadap zona hambat amoksisilin dan kloramfenikol terhadap Staphylococcus aureus.Metode: Ekstraksi dilakukan dengan maserasi menggunakan kloroform dan soxhletasi menggunakan methanol. Fraksinasi dengan pelarut, yaitu aquadest, methanol dan etil asetat. Uji fitokimia secara kualitatif dengan melihat perubahan warna. Uji Zone of Inhibition (ZOI) dilakukan untuk mengetahui efek dari kombinasi fraksi alkaloid I.cylindrica L. dengan antibiotik terhadap S.aureus dengan metode Kirby-Bauer. Diameter zona bening diukur menggunakan jangka sorong, dan interpretasi hasil berdasarkan metode Ameri-Ziaei Double Antibiotic Synergism Test (AZDAST).Hasil : Fraksi – fraksi alkaloid I.cylindrica L. tunggal tidak membentuk zona bening terhadap S.aureus. Kombinasi fraksi alkaloid dengan kloramfenikol (F1C dan F2C) memiliki ZOI dengan rerata diameter 30.73 ± 0.9 mm dan 30.53 ± 0.55 mm, yang lebih besar dari ZOI kloramfenikol tunggal yaitu 28.6 ± 0.95 mm dan fraksi tunggal 0 ± 0 mm. Pada uji fitokimia ditemukan bahwa senyawa yang terkandung adalah alkaloid.Simpulan: Alkaloid merupakan senyawa aktif dari I.cylindrica L.. Fraksi alkaloid I.cylindrica L. bersifat potensiasi dengan antibiotik kloramfenikol terhadap S.aureus karena mampu meningkatkan kinerja antibiotik tersebut.

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Maharjan, Renuka, Saru Thapa et Amrit Acharya. « Evaluation of Antimicrobial Activity and Synergistic Effect of Spices against Few Selected Pathogens ». Tribhuvan University Journal of Microbiology 6 (6 décembre 2019) : 10–18. http://dx.doi.org/10.3126/tujm.v6i0.26573.

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Objectives: The main objective of this study was to evaluate antimicrobial activity of ethanolic extract of spices along with determination of its synergistic effect against few selected pathogens. Methods: In this study, ethanolic extract of 5 different spices; Zingiber officinale (Ginger), Allium sativum (Garlic), Curcuma longa (Turmeric), Capsicum annum (Chili) and Allium cepa (Onion) were obtained by using Soxhlet apparatus. The ethanolic extract was concentrated by evaporation and different concentrations of extract were prepared in Dimethy Sulphoxide (DMSO) solvent. Test organisms included mainly pathogens i.e. Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae. The antimicrobial activities of the extracts were determined by well diffusion technique both individually and in combination. On the other hand, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) was determined by serial dilution technique. The result were interpreted on the basis of the fact that the growth occurs in positive control and other tubes with inadequate amount of extract whereas the lowest concentration of agent that inhibits growth of organism, detected by lack of visible turbidity by inhibition of 99% is designed as the MIC. The MBC is identified by determining the lowest concentration of extract solution that reduces the viability of the initial bacterial inoculum by a predetermined reduction such as ≥99.9%. Likewise, for determination of Fractional Inhibitory Concentration Index (FICI), two extracts were combined along with standardized inoculum of bacterial strain. Tubes without visible turbidity were streaked on agar plate and observed for 99.9% killing. Results: All the tested extract of spices were found effective against S. aureus and K. pneumoniae only. The highest zone of inhibition (ZOI) was found in chili extract (ZOI=26 mm) against S. aureus whereas lowest zone of inhibition was found in garlic extract against K. pneumoniae (ZOI=12mm). Similarly, highest ZOI was produced by combined extract of both Turmeric and Ginger (ZOI= 26 mm). Turmeric extract was found to be effective against S. aureus (MIC value = 62.5 mg /ml and MBC value = 31.25 mg/ml) and K. pneumoniae (MIC value 125 mg/ml and MBC value = 62.5 mg/ml). The Fractional Inhibitory Concentration (FIC) values of combined extract suggested synergistic and additive effect (0.5<FIC<1). Chili and ginger were effective with FIC value of 0.25. Conclusion: To recapitulate, the extract of spices can be used to prevent the pathogenic organism.

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Singariya, Premlata, Mourya Krishan Kumar et Padma Kumar. « COMPARATIVE STUDY OF ANTIBACTERIAL PROPERTIES OF FLAVONOIDS OF LEAVES FROM DIFFERENT CACTUS, PERENNIAL GRASSES AND MEDICINAL PLANT ». Asian Journal of Pharmaceutical Research and Development 6, n^o 3 (10 juillet 2018) : 32–41. http://dx.doi.org/10.22270/ajprd.v6i3.372.

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Comparative study of antibacterial properties of flavonoids of leaves from different Cactus (Euphorbia caducifolia); perennial grasses(Panicum antidotale and Lasiurus sindicus) and medicinal plant (Anaegissus rotundifolia) against some important bacteria (G+ve or G-ve) was done. Flavonoid extracts of leaves from all the selected plants were found to possess strong antibacterial activity against these test pathogenic microbes, as revealed by ZOI=(mm± SD), AI, MIC=(mg/ml), MMC=(mg/ml) and TA=(ml/gm) of extracts against each sensitive test pathogenic bacteria were also evaluated. Most of the pathogens were found to be sensitive against these flavonoid extracts. Free flavonoid extract of grasses and medicinal plant showed higher activity against most of the pathogens. Euphorbia caducifolia is the most inactive plant in this study. All pathogens didn’t show any activity against Euphorbia caducifolia except Proteus mirabilis which show 7.83±0.21 mm ZOI for free flavonoid. Highest ZOI (18.67±0.26) was recorded for free flavonoid of medicinal plant (Anaegissus rotundifolia) against Bacillus subtilis (G+ve bacteria) as well as other parameters like AI (1.245), MIC (0.039 mg/ml), MMC (0.78 mg/ml) were found higher against Bacillus subtilisand highest TA (1012.821 ml/gm) were found highest for free flavonoid of Lasiurus sindicus against Bacillus subtilis. The findings of the present study suggested the exploitation of flavonoid extracts of Anaegissus rotundifoliaand of Lasiurus sindicusfor future antibacterial drugs.

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Santosh Kumar, P., S. Vidhya et S. Mahalaxmi. « Antimicrobial Efficacy of Various Concentrations of Bamboo Salt against Enterococcus faecalis and Candida albicans : An in vitro Study ». Journal of Operative Dentistry & ; Endodontics 2, n^o 2 (2017) : 65–68. http://dx.doi.org/10.5005/jp-journals-10047-0039.

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ABSTRACT Sodium hypochlorite (NaOCl) remains the gold standard against which any new endodontic irrigant is compared. But, its inadvertent extrusion beyond the confines of the root canal can be caustic to vital periapical or periodontal tissues. There has been an increase in the use of herbal medicines as irrigants over the last two decades. Bamboo salt is a Korean folk medicine, which shows promising antimicrobial, antioxidant, and anti-inflammatory properties. The aim of this in vitro study was to comparatively evaluate the effectiveness of 1, 3, and 5% bamboo salt against Enterococcus faecalis and Candida albicans using agar diffusion test; 4% NaOCl was used as control. The experiment was performed in triplicate and the zone of inhibition (ZOI) was measured. The results of the present study showed that 4% NaOCl and 5% bamboo salt showed significantly higher mean ZOI than the other groups against E. faecalis; 4% NaOCl showed significantly higher mean ZOI than the other groups against C. albicans, followed by 5 and 3% bamboo salt. Hence, it can be concluded that 4% NaOCl proved to be the most effective antimicrobial against both the species; 5% bamboo salt was as effective as 4% NaOCl against E. faecalis, but significantly less effective against C. albicans. How to cite this article Santosh Kumar P, Vidhya S, Mahalaxmi S. Antimicrobial Efficacy of Various Concentrations of Bamboo Salt against Enterococcus faecalis and Candida albicans: An in vitro Study. J Oper Dent Endod 2017;2(2):65-68.

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Momtaz, Hossein Emad, Shirin Moradkhan, Mohammad Yousef Alikhani, Farzaneh Esnaashari et Mojdeh Afkhami. « Study of antimicrobial effect of some plants of Lamiaceae family on Escherichia coli species isolated from children with urinary tract infection ». Journal of Renal Injury Prevention 8, n^o 1 (26 février 2018) : 38–43. http://dx.doi.org/10.15171/jrip.2019.08.

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Introduction: Urinary tract infection (UTI) has a high prevalence in children. It is an important cause of renal scar, chronic renal disease, failure to thrive and hypertension. The unnecessary consumption of antibiotics results in the bacterial resistance to most common drugs. In addition, possible drug allergic reaction and side effects should be considered. Therefore, finding new antimicrobial compounds is necessary. Objectives: In this study, the antimicrobial effect of some plants of Lamiaceae family on Escherichia coli in comparison with common antibiotics used in UTI was investigated. Materials and Methods: In this experimental study, the hydroalcoholic extract of 13 plant species from Lamiaceae family were prepared and their antimicrobial effects were assessed by the agar well diffusion method. In addition, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were investigated using the serial dilution method. The zone of inhibition (ZOI) of the growth of E. coli was compared between the studied extracts and five most common antibiotics in the treatment of UTI. Results: The mean diameter of ZOI was significantly higher for amikacin than the studied extracts and other antibiotics. Among the herbal extracts, the highest ZOI was observed for Nepeta crispa. In addition, the MIC and MBC of N. crispa were significantly lower than other extracts. Conclusion: According to the side effects and relatively high cost of chemical and synthetic drugs, use of herbal extracts, such as N. crispa may be recommended as an alternative treatment of UTI with E. coli. The results of present study are promising to introduce new candidates in the treatment of UTI.

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Bhandari, Ganesh, Basant Pokhrel, Yogesh Oli, Archana Katuwal et Netra Lal Bhandari. « Screening of Methicillin Resistant Staphylococcus aureus (MRSA) from Wounds in Pediatric Patients Visiting Tertiary Care in Hospital ». Nepal Journal of Biotechnology 7, n^o 1 (29 décembre 2019) : 82–89. http://dx.doi.org/10.3126/njb.v7i1.26957.

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The extent of methicillin-resistant Staphylococcus aureus (MRSA) in children is still unknown. The collected wound pus samples were processed. Identification of S. aureus was done according to standard microbiological procedures as per the clinical laboratory standards institute (CLSI) guidelines (2016). The antibiogram of the isolates was carried out by the Kirby-Bauer disc diffusion technique. MRSA was determined by measuring the zone of inhibition (ZOI) surrounding to cefoxitin disc, with resistance defined as ZOI of ≤ 21 mm. Out of 357 bacterial culture-positive samples, 278 (77.87 %) were S. aureus isolates, among them 102 (36.69%) were found to be MRSA. The percentage of MRSA isolates was found high in male children and inpatients with 61.76 % and 73.52% respectively. All the MRSA isolates were susceptible to gentamicin (79.41%), whereas (91.17%) were resistant to penicillin. The distribution of MRSA in inpatients 75 (73.52%) is higher than that of outpatients 27 (26.74%). This study shows that the MRSA occurrence is prevalent in pediatric patients.

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Kunwor, Rup Bahadur, et Olivia Thapa. « Evaluation of Antibacterial Properties of some Medicinal Plants used for the Treatment of Respiratory Tract Infections in Nepal ». Tribhuvan University Journal 28, n^o 1-2 (2 décembre 2013) : 262–66. http://dx.doi.org/10.3126/tuj.v28i1-2.26253.

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The present work was designed to evaluate the antibacterial properties of the ethanol extracts of five selected medicinal plants Azadirachta indica, Ocimum sanctum, Jasminium humile, Glycyrrhiza glabra and Acorus calamus on bacteria causing respiratory tract infections. Almost all the tested medicinal plants showed inhibitory effect against the test organisms. Among the medicinal plants evaluated Ocimum sanctum was found effective against most of the testorganisms except Pseudomonas aeruginosa. The growth of Staphylococcus aureus was inhibited by all tested plant extracts with highest zone of inhibition by G. glabra with ZOI value 23 mm and MBC value 0.39 mg/ml in ethanol suspension. Among the test organisms K. pneumoniae was found more resistant towards the test plant extracts. This bacterium was inhibited only by J. humile with ZOI value 13 mm and MBC value 6.25 mg/ml in alcohol solution. The present work evidently provides information on the role of some medicinal plants in the fight against bacteria causing respiratory tract infections.

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Sympli, Hakani D., Supriyo Sen, Bahunlang Susngi et Vedant Vikrom Borah. « Quantitative Phytochemical Analysis Reveals Significant Antibiofilm Activity in Pleione maculata, an Endangered Medicinal Orchid ». Journal of Pure and Applied Microbiology 15, n^o 3 (20 août 2021) : 1573–90. http://dx.doi.org/10.22207/jpam.15.3.51.

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Pleione maculata has no scientific reports on quantitative phytochemical and antibiofilm activity till date. The objective of the study was to quantify and determine medicinally important bioactivity in P. maculata and analyse its anti-biofilm activity against clinical isolates Staphyloccocus aureus, Klebsiella pneumoniae and Proteus mirabilis. P. maculata exhibited the highest Total Antioxidant Capacity (TAC) about 193.98±0.1 mg, highest Total Phenolic Content (TPC) at 552±0.0 mg and Total Flavonoid Content (TFC) were observed highest at 879.5±0.2 mg. The acetone and ethyl acetate extracts of P. maculata pseudobulb showed distinct and significant zone of inhibition (ZOI) against drug-resistant S.aureus about 16±0.00 mm (MIC 0.875 mg/mL), ZOI of acetonitrile pseudobulb extract against P. mirabilis was 15.33±0.4 mm (MIC 1 mg/mL), ZOI of acetonitrile extracts of leaves and stem, ethyl acetate extract of pseudobulb was 12±0.0 mm, 12±01.4 mm, 12±2.8 mm against K. pneumoniae (MIC 1.8 mg/mL, 0.68 mg/mL and 3 mg/mL). Acetonitrile extract of pseudobulbs exhibited the highest Minimum Biofilm Inhibition concentration (MBIC) at 0.25 mg/mL against S. aureus, water root extract inhibited attachment of K. pneumoniae with lowest MBIC value 0.093 mg/mL, water and acetone extract of leaves inhibited cell attachment of P. mirabilis at lowest MBIC 0.117 and 0.171 mg/mL. The UV-VIS absorption band of P. maculata extracts ranges from 204-665 nm indicating the presence of phenolic and flavonoid compounds. The study indicates the potentiality of P. maculata as a rich source of medicinal active compounds as an antibiofilm agent against antibiotic-resistant clinical isolates.

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Mohapatra, D. P., V. Thakur et S. K. Brar. « Antibacterial Efficacy of Raw and Processed Honey ». Biotechnology Research International 2011 (29 décembre 2011) : 1–6. http://dx.doi.org/10.4061/2011/917505.

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In vitro antibacterial activity of methanol, ethanol, and ethyl acetate extracts of raw and processed honey was tested against Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Enterococcus faecalis, and Micrococcus luteus) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi). Both types of honey showed antibacterial activity against tested organisms with the zone of inhibition (ZOI) ranging from 6.94 to 37.94 mm, while E. coli, S. typhi, and P. aeruginosa showed that sensibility towards all the extracts with ZOI ranges between 13.09 to 37.94 mm. The methanol extract showed more potent activity than other organic extracts. Gram-negative bacteria were found to be more susceptible as compared to Gram-positive bacteria except E. faecalis. The broth microdilution assay gave minimum inhibitory concentrations (MIC) value of 625 μg/mL, while the minimum bactericidal concentration (MBC) ranges between 625 μg/mL 2500 μg/mL. The study showed that honey has antibacterial activity (bacteriostatic and bactericidal effect), similar to antibiotics, against test organisms and provides alternative therapy against certain bacteria.

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M. El-Khawaga, Ahmed, Ayman A. Farrag, Ahmed I. El-Batal et Mohamed A. Elsayed. « Evaluation of the Antimicrobial Activity of Citric Acid Functionalized Magnetite Nanoparticles ». Egyptian Journal of Medical Microbiology EJMM29, n^o 4 (1 octobre 2020) : 143–49. http://dx.doi.org/10.51429/ejmm29418.

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Background: Antimicrobial resistance (AMR) has emerged as one of the principal public health problems of the 21st century that threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria no longer susceptible to the common medicines used to treat them. Objectives: To development of Fe3O4 NPs with specific sizes and shapes Potential as a new antibacterial agent. Methodology: In this study magnetite nanoparticles (Fe3O4 NPs) were synthesized through an aqueous co-precipitation method and functionalized with citric acid for outstanding their antimicrobial potential. Fe3O4 NPs were characterized by XRD, TEM, SEM, EDX and FTIR to analyze crystallinity, average particle size, morphology and functional groups, respectively. Antimicrobial activity was investigated against pathogenic bacteria as zone of inhibition (ZOI) and minimum inhibitory concentration (MIC). Results: Antimicrobial results showed that CA- Fe3O4 NPs owns maximum activity against Staphylococcus aureus and E. coli by 18.0 and 15.0mm ZOI, respectively. Conclusion: It should be noted that (CA-Fe3O4) NPs are also active upon Gram-positive than Gram- negative bacteria. The synthesized (CA-Fe3O4) NPs are promising for potential applications as antimicrobial agent and in drug delivery fields.

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Laycock, Phillip, John Cooper, Robert Howlin, Craig Delury, Sean Aiken et Paul Stoodley. « In Vitro Efficacy of Antibiotics Released from Calcium Sulfate Bone Void Filler Beads ». Materials 11, n^o 11 (13 novembre 2018) : 2265. http://dx.doi.org/10.3390/ma11112265.

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15 different antibiotics were individually mixed with commercially available calcium sulfate bone void filler beads. The antibiotics were: amikacin, ceftriaxone, cefuroxime, ciprofloxacin, clindamycin, colistamethate sodium, daptomycin, gentamicin, imipenem/cilastatin, meropenem, nafcillin, rifampicin, teicoplanin, tobramycin and vancomycin. The efficacy of specific released antibiotics was validated by zone of inhibition (ZOI) testing using a modified Kirby–Bauer disk diffusion method against common periprosthetic joint infection pathogens. With a subset of experiments (daptomycin, rifampin, vancomycin alone and rifampin and vancomycin in combination), we investigated how release varied over 15 days using a repeated ZOI assay. We also tested the ability of these beads to kill biofilms formed by Staphylococcus epidermidis 35984, a prolific biofilm former. The results suggested that certain antibiotics could be combined and released from calcium sulfate with retained antibacterial efficacy. The daptomycin and rifampin plus vancomycin beads showed antimicrobial efficacy for the full 15 days of testing and vancomycin in combination with rifampin prevented resistant mutants. In the biofilm killing assay, all of the antibiotic combinations showed a significant reduction in biofilm bacteria after 24 h. The exposure time was an important factor in the amount of killing, and varied among the antibiotics.

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Harrison, Jerry Joe E. K., Moscoh Daniel Ayine-Tora, Benjamin Appiagyei, Felix C. Mills-Robertson, William A. Asomaning, Daniel G. Achel, Hiroyuki Ishida et Robert Kingsford-Adaboh. « Crystal structure and in vitro antimicrobial activity studies of Robustic acid and other Alpinumisoflavones isolated from Millettia thonningii ». Zeitschrift für Kristallographie - Crystalline Materials 234, n^o 4 (24 avril 2019) : 229–35. http://dx.doi.org/10.1515/zkri-2018-2052.

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Abstract We report a systematic study of the antibacterial inhibitory potential of isoflavone natural products isolated from the seeds extracts of Millettia thonningii. In an effort to gain bond topological information which may have consequences for the observed bioactivities, the crystal structure of robustic acid was solved and refined using the independent atom as well as the invariom model, and the structures were compared. Robustic acid contains a fused tricyclic unit with a benzopyran moiety, with a phenylene ring substitution on the coumarin ring similar to the alpinumisoflavones isolated from this plant. At a minimum inhibitory concentration of ~1 mg/mL, alpinumisoflavone and robustic acid were found to be cytotoxic to Staphylococcus aureus (ATCC 25923) showing a zone of inhibition (ZOI) of ~9 mm. On the other hand, at ~2 mg/mL, these compounds were found to be bacteriostatic to a hospital isolate of Salmonella typhi with about 7 mm ZOI. Taken together, these compounds offer potential new avenues for targeting both Gram positive and negative bacteria and could be useful as chemical probes for understanding these pathogens in an effort to overcome drug resistance.

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Arikan, Sevtap, Pınar Yurdakul et Gulsen Hascelik. « Comparison of Two Methods and Three End Points in Determination of In Vitro Activity of Micafungin against Aspergillus spp ». Antimicrobial Agents and Chemotherapy 47, n^o 8 (août 2003) : 2640–43. http://dx.doi.org/10.1128/aac.47.8.2640-2643.2003.

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ABSTRACT We investigated the in vitro activity of micafungin against clinical Aspergillus isolates (n = 37) (Aspergillusfumigatus [n = 21], Aspergillusflavus [n = 14], and Aspergillus niger [n = 2]) by using NCCLS M38A microdilution and an investigational disk diffusion assay. Microdilution assay results were evaluated by using the end points of a MIC-2 (measured in micrograms per milliliter) and minimum effective concentration (MEC, measured in micrograms per milliliter; the lowest concentration of micafungin that produces short and aberrant hyphal branchings microscopically). Disk diffusion results were interpreted by measuring the zone(s) of inhibition (ZOI, measured in millimeters). Micafungin proved to be similarly active against all Aspergillus species tested. At 24 h, MIC-2s and MECs were identical. At 48 h, however, MIC-2s increased unpredictably, leading to the loss of a consistent correlation between the two end points. MECs and ZOI remained consistent and correlated at both reading times, suggesting their use as relevant end points in susceptibility testing of micafungin against Aspergillus. All Aspergillus isolates yielded intrazonal growth on disk diffusion agar plates. The intrazonal colonies contained short, aberrant hyphal branchings microscopically. The in vivo significance of these findings remains to be further investigated.

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Pal, A. D., et T. M. Zakir. « Analysis of Proximate Composition and Functional Properties of Selected Edible Leaves : Nutritional and Therapeutic Implication ». Journal of Scientific Research 12, n^o 4 (1 septembre 2020) : 621–32. http://dx.doi.org/10.3329/jsr.v12i4.45110.

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The present study was designed to document the nutritional and functional properties of Ceylon Spinach, Mustard as well as Pumpkin leaves. These samples were selected owing to their economic affordability and utilization within the local population. Proximate analysis revealed a significant percentage of minerals, proteins, carbohydrates and vitamin C in all the leaf extracts. Phytochemical screening displayed Ceylon Spinach, Pumpkin and Mustard leaves to be rich sources of polyphenols (106.6, 76.24 and 89.86 mg/100 g) and alkaloids (12.8 %, 13.2 % and 16.8 %) respectively. Furthermore, these edible leaves could effectively scavenge 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) and hydrogen peroxide (H2O2) free radicals with Mustard leaves showing the greatest efficiency, hence portraying antioxidant properties. Ceylon Spinach leaves depicted the highest reducing power compared to the other samples. Additionally, the edible leaf extracts were shown to possess anti-bacterial abilities with Mustard leaves displaying the strongest inhibition against growth of both Gram positive (ZOI 18.5mm) and negative bacteria (ZOI 25.5mm). Interestingly, the selected samples could also elevate the growth of probiotic Lactobacillus acidophilus in vitro thereby confirming their prebiotic potential. Therefore, inclusion of these edible leaves in the diet may promote good health owing to their nutritional and therapeutic benefits.

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Hakonen, Bodil, Linnea K. Lönnberg, Eva Larkö et Kristina Blom. « A Novel Qualitative and Quantitative Biofilm Assay Based on 3D Soft Tissue ». International Journal of Biomaterials 2014 (2014) : 1–5. http://dx.doi.org/10.1155/2014/768136.

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The lack of predictablein vitromethods to analyze antimicrobial activity could play a role in the development of resistance to antibiotics. Current used methods analyze planktonic cells but for the method to be clinically relevant, biofilm inin vivolike conditions ought to be studied. Hence, our group has developed a qualitative and quantitative method within vivolike 3D tissue for prediction of antimicrobial activity in reality. Devices (wound dressings) were applied on top ofPseudomonas aeruginosainoculated Muller-Hinton (MH) agar or 3D synthetic soft tissues (SST) and incubated for 24 hours. The antibacterial activity was then analyzed visually and by viable counts. On MH agar two out of three silver containing devices showed zone of inhibitions (ZOI) and on SST, ZOI were detected for all three. Corroborating results were found upon evaluating the bacterial load in SST and shown to be silver concentration dependent. In conclusion, a novel method was developed combining visual rapid screening and quantitative evaluation of the antimicrobial activity in both tissue and devices. It uses tissue allowing biofilm formation thus mimicking reality closely. These conditions are essential in order to predict antimicrobial activity of medical devices in the task to prevent device related infections.

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Chomini, M. S., M. K. Peter, M. Ameh, A. E. Chomini, E. A. Bassey et A. O. Ayodele. « Phytochemical Screening and Antibacterial Activities of Aframomum melegueta (K. Schum) Seed Extracts on Salmonella typhi and Klebsiella pneumoniae ». Journal of Applied Sciences and Environmental Management 24, n^o 8 (9 septembre 2020) : 1419–24. http://dx.doi.org/10.4314/jasem.v24i8.17.

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The phytochemical screening and antibacterial effects of Aframomum melegueta (K. Schum)on Salmonella typhi and Klebsiella pneumoniae was carried out. The phytochemical screening revealed the presence of alkaloids, flavonoids, tannins, saponins, steroids, anthraquinones, terpenoids, glycosides and phenols in the seed extract. The susceptibility test showedzones of inhibition (ZOI) of S. typhi (11.0mm) and K. pneumonia (13.0mm)with methanolic seed extract (MSE), while the hot aqueous seed extract (HASE) recorded 3.0mmas ZOI for both test organisms. The Minimum inhibitory concentration (MIC) of 200mg/ml and 100mg/ml were recorded against S. typhi and K. pneumoniae respectively with MSE, while HASE indicated 400mg/ml and 200mg/ml MICs against S. typhi and K. pneumoniae respectively. The Minimum Bactericidal Concentration (MBC) obtained from MSE were 200 mg/ml and 25mg/ml for S. typhiand K. pneumoniae, while HASE had > 400mg/ml for test microbes. The effectiveness of different concentrations of the test plant extracts on the test organisms was significant (P<0.05). Further trials involving other clinical isolates and botanicals at different concentrations be conducted, to optimize theprocess. Keywords: Phytochemical, Antimicrobial, Aframomum melegueta, Salmonella typhi, Klebsiella pneumoniae

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Sharma, Khaga Raj, et Rupak Kharel. « Antibacterial, Antidiabetic and Brine Shrimp Lethality Activities of Some Selected Medicinal Plants from Kavrepalanchok District of Nepal ». Journal of Institute of Science and Technology 24, n^o 1 (26 juin 2019) : 57–62. http://dx.doi.org/10.3126/jist.v24i1.24629.

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The methanol extracts of nine medicinal plants collected from Kavrepalanchok district of Nepal were subjected to their potential bioactivity viz. antibacterial, antidiabetic and toxicity tests. Antibacterial property of the extracts was evaluated against Gram-positive and Gram-negative bacteria by agar well diffusion method and antidiabetic activity was investigated by α-amylase inhibition assay. The toxicity of plant extracts was assessed by brine shrimp lethality test. All the nine different plant extracts showed antibacterial activity with the zone of inhibition (ZOI) ranging from 5 to 35 mm. Among the studied plant extracts, Psidium guajava showed the highest ZOI against Salmonella typhi (35 mm) while Melia azedarach was most effective against Staphylococcus aureus (22 mm). The percentage of α- amylase enzyme inhibition was found up to 88.56 ± 3.50 in dose dependent manner. The enzyme inhibitory concentration IC50 value of standard, acarbose was 166.01 μg/mL while the most effective anti-diabetic plant extract of Utrica dioica has 186.67 μg/mL. Moreover, various plant extracts depicted various levels of toxic activities; Curcuma longa demonstrated significant toxicity to Artemia salina with LC50 value 62.10 μg/mL, while Agerantina adenophora, P. guajava and M. azedarach showed moderate toxicity with 103.77, 109.37 and 383.58 μg/mL, respectively.

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Lekhak, Binod, Anjana Singh et Dwij Raj Bhatta. « Antibacterial and Antifungal Property of Actinomycetes Isolates from Soil and Water of Nepal ». Journal of Nepal Health Research Council 16, n^o 2 (5 juillet 2018) : 136–39. http://dx.doi.org/10.3126/jnhrc.v16i2.20298.

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Background: Human pathogens are rapidly acquiring resistance to antibiotics leading to treatment failure. We carried out this study to isolate and screen actinomycetes strains that have potential to kill bacterial and fungal pathogens.Methods: In this descriptive study 288 soil and water samples were processed by standard microbiological techniques at Central Department of Microbiology, Tribhuvan University from 2013 to 2015. Screened actinomycetes were cultivated for bioactive metabolite production and minimum inhibitory concentration (MIC) of metabolites were determined against bacterial pathogens including multidrug resistant bacteria and fungi.Results: One hundred twenty isolates having antimicrobial property were screened. Out of them, four most potent strains, Nocardiopsis prasina, Streptomyces violarus, Streptomyces krainskii and Streptomyces tsusimaensis were identified all having both antibacterial and anti-fungal property.Highest zone of inhibition (ZOI)was given by N. prasina against Candida albicans(41.33 ±1.15mm) and among bacteria, maximum ZOI was against Acinetobacter baumannii(31.33±3.05mm). MIC value of metabolite of N.prasina was 0.125mg/ml for E.coli and C. albicans. It was 2.5 mg/ml each for methicillin resistant Staphylococcus aureus (MRSA), A. baumannii and Salmonella Typhi and 0.625 mg/ml for Bacillus Subtilis.Conclusions: Bioactive metabolite producing actinomycetes were recovered from soil and tested against human pathogenic bacteria and fungiand found to have antibacterial and antifungal property.

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Satar, Rukhsana, Syed Ahmed Iizhar, Mahmood Rasool, Peter Natesan Pushparaj et Shakeel Ahmed Ansari. « Investigating the antibacterial potential of agarose nanoparticles synthesized by nanoprecipitation technology ». Polish Journal of Chemical Technology 18, n^o 2 (1 juin 2016) : 9–12. http://dx.doi.org/10.1515/pjct-2016-0022.

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Abstract Herein, an effort was made to investigate the antibacterial potential of agarose nanoparticles (ANPs) and poly(quaternary ammonium) modified ANPs (mANPs) against Escherichia coli (gram-negative bacterium) and Staphylococcus aureus (gram positive bacterium) in liquid systems as well as on agar plates. ANPs were synthesized by nanoprecipitation technology and characterized by XRD, TEM, TGA, DTA and DLS. The particle size estimated was 30 nm while atomic force microscopy was used to observe the interaction of ligand on ANPs. Antimicrobial characterization was monitored by colony forming units (CFU) as a function of ANPs concentration on agar plates. It was observed that ANPs showed 15 × 109/ml CFU after 24 hours of incubation at 20 mM ANPs concentration while the modified ANPs exhibited 21 × 109/ml CFU under similar incubation conditions. Moreover, zone of inhibition (ZOI) was 2.9 and 3.8 cm, respectively for E. coli by ANPs at 0.2 and 0.4 mM, respectively while it was 3.2 and 3.8 cm respectively by modified ANPs under similar conditions. Similarly, ZOI for S. aureus by ANPs at 0.2 and 0.4 mM was observed at 3.1 and 4.0 cm, respectively, while these values were 3.5 and 4.1 cm, respectively for modified ANPs under similar incubation conditions.

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Gungor, Ebru, et Tayyar Gungor. « Effect of the Substrate Movement on the Optical Properties of ZnO Thin Films Deposited by Ultrasonic Spray Pyrolysis ». Advances in Materials Science and Engineering 2012 (2012) : 1–7. http://dx.doi.org/10.1155/2012/594971.

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Using a modified ultrasonic spray pyrolysis (USP) system, ZnO thin films were deposited on the substrate moved back and forth (ZO1) and rotated (ZO3) as well as fixed (ZO2) in the conventional USP technique. Prepared thin films are pure ZnO with a preferred crystalline orientation of (0 0 2) in the hexagonal wurtzite structure. Diffraction angle shift implies a decrease lattice parameter alongc-axis anda-axis 0.2% and 0.3%, respectively. Maximum strain has been found for ZO1 which is about (−) 0.17%. These strain values show that presence of compressive strain due to moving substrates as depositing ZnO films. The film deposition process on the rotated quartz substrate is provided to obtain the thinner film. The grain size and root-mean- square value of roughness increase with thickness. Strong UV emission was observed at ∼390 nm assigned to the band gap transition from photoluminescence measurements. Energy shifted about 39 meV for ZO3 sample with respect to that of ZO2 film deposited in conventional USP system. This behaviour is confirmed with (002) diffraction peak shifting. So, the compressed lattice will provide a wider band gap for these films.E2phonon frequency values have not given a considerable shifting.

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Subba, Bimala, et Pramod Aryal. « Study of Biological Activity and Chemical Constituent of Annona Reticulata ». Journal of Institute of Science and Technology 21, n^o 1 (24 novembre 2016) : 157–63. http://dx.doi.org/10.3126/jist.v21i1.16068.

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The methanol and hexane extract of leaf of Annona reticulata, vernacularly known as ‘Sareefa’ were subjected to biological assay and column chromatography respectively. Column chromatography of the hexane extract of the leaf of A. reticulata resulted in the isolation of one pure compound PF1. The compound PF1 was suggested as β-sitosterol by comparing TLC, IR and melting point with authentic sample. The antibacterial activity against two bacteria, Staphylococcus aureus (gram positive) and Escherichia coli (gram negative) was done by agar well diffusion method and Zone of Inhibition (ZOI) was observed. The ZOI obtained ranged from 8 to 12 mm. The methanol extract of leaf showed moderate antibacterial activity on comparison with standard antibiotic streptomycin. The Antioxidant activity of the extract was tested using scavenging activity of DPPH (1, 1-Diphenyl-2- Picrylhydrazyl) radical method. The IC50 value of A. reticulata was found (41 µg/ml). The standard compound has shown IC50 value as 120 µg/ml. The antimicrobial and antioxidant activity of the extract was positively associated with the total phenolic and flavonoid contents of the extract. This study revealed that methanolic leaf extract of A. reticulata comprise effective potential source of natural antioxidant, which might be helpful in preventing the progress of various oxidative stresses.Journal of Institute of Science and TechnologyVolume 21, Issue 1, August 2016, page: 157-163

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Haq, Anika, Suneel Kumar, Yong Mao, Francois Berthiaume et Bozena Michniak-Kohn. « Thymoquinone-Loaded Polymeric Films and Hydrogels for Bacterial Disinfection and Wound Healing ». Biomedicines 8, n^o 10 (28 septembre 2020) : 386. http://dx.doi.org/10.3390/biomedicines8100386.

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The purpose of this study was to synthesize and characterize novel biocompatible topical polymeric film and hydrogel systems that have the potential to deliver the antibacterial agent thymoquinone (TQ) directly to the skin target site to manage the local wound infection and thereby wound healing. The polyvinyl pyrrolidone (PVP) matrix-type films containing TQ were prepared by the solvent casting method. In vitro skin permeation studies on human cadaver skin produced a mean flux of 2.3 µg TQ/cm2/h. Human keratinocyte monolayers subjected to a scratch wound (an in vitro wound healing assay) showed 85% wound closure at day 6 in the TQ group (100 ng/mL TQ) as compared to 50% in the vehicle control group (p = 0.0001). In a zone-of-inhibition (ZOI) assay, TQ-containing films and hydrogels completely wiped out Staphylococcus aureus in 10 cm diameter Tryptic Soy Agar plates while 500 µg/mL gentamicin containing filters gave 10 mm of ZOI. In an ex vivo model, TQ-containing films eradicated bacterial colonization on human cadaver skin. Furthermore, in a full-thickness wound infection model in mice, TQ-containing films showed significant activity in controlling Staphylococcus aureus infection, thereby disinfecting the skin wound. In summary, TQ-containing PVP films and hydrogels developed in this study have the potential to treat and manage wound infections.

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Phuyal, Nirmala, Pramod Kumar Jha, Pankaj Prasad Raturi et Sangeeta Rajbhandary. « In Vitro Antibacterial Activities of Methanolic Extracts of Fruits, Seeds, and Bark of Zanthoxylum armatum DC ». Journal of Tropical Medicine 2020 (4 juin 2020) : 1–7. http://dx.doi.org/10.1155/2020/2803063.

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Crude methanol extracts of fruits, seeds, and bark of Zanthoxylum armatum were investigated in vitro for antimicrobial activities against 9 different bacterial strains: Bacillus subtilis, Enterococcus faecalis, Proteus vulgaris, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysenteriae, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Staphylococcus epidermidis using agar well diffusion method, and the MBC values were determined. Only 5 bacteria, i.e., Bacillus subtilis, Enterococcus faecalis, MRSA, Staphylococcus aureus, and Staphylococcus epidermidis exhibited antibacterial properties against the different extracts. The fruit and seed extracts showed activities against 5 bacteria, while the bark extract was active against 2 bacteria only (MRSA and Staphylococcus aureus). Staphylococcus aureus was found to be more susceptible for all the extracts compared to other strains. The maximum ZOI of 20.72 mm was produced by fruits (wild) and 18.10 mm (cultivated) against Staphylococcus aureus. Likewise, the least ZOI of 11.73 mm was produced by seeds (wild) and 11.29 mm (cultivated) against Escherichia faecalis. Similarly, the lowest MBC value of 0.78 mg/mL was obtained for fruit extracts against MRSA, 1.56 mg/mL for fruits, seeds, and bark extracts against Bacillus subtilis, MRSA, and Staphylococcus aureus, and highest value of 50 mg/mL for fruits and seeds extracts against S. epidermidis. The fruits, seeds, and bark extracts of Z. armatum exhibited remarkable antibacterial properties against different pathogenic bacteria causing several diseases, which suggests the potential use of this plant for treating different bacterial diseases such as skin infection, urinary tract infection, dental problems, diarrhea, and dysentery.

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ALI, MAHBOOB, MUHAMMAD AVAIS, MUHAMMAD AMEEN JAMAL, MUHAMMAD IJAZ, MAMOONA CHAUDHRY, AMJAD ISLAM AQIB, MUMTAZ ALI KHAN et al. « Combating multidrug-resistant Staphylococcus aureus isolated from camel milk with extracts of Eucalyptus globulus and Calotropis procera, and their potential role in modulation of resistance to beta-lactam drugs ». Medycyna Weterynaryjna 77, n^o 10 (2021) : 6583–2021. http://dx.doi.org/10.21521/mw.6583.

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This study aimed to evaluate the efficacy of Eucalyptus globulus and Calotropis procera against MDRSA and their potential role in modulating resistance to beta-lactam drugs. The study used a total of n = 263 camel milk samples as well as aqueous and ethanolic extracts of both plants from the Cholistan Desert and the Suleman Mountain Range in Pakistan. Different concentrations of the two plants (25, 12.6, 6.25, and 3.125 mg/mL), either alone or in combination with each other, were tested against MDRSA by well diffusion and broth dilution methods. Further, the efficacy of both plant extracts in combination with cefotaxime (30 μg) and ampicillin (1 μg) was also tested. The results indicate that the zone of inhibition (ZOI) of E. globulus alone and in combination with C. procera was nearly 3 times as large as that of C. procera. Ethanolic extracts of the two plants plants, alone or in combination with either of the two antibiotics, had a significantly (P <0.05) larger ZOI than their aqueous extracts did. Further, the modulation factor for the drugs in combination with ethanolic extracts of both plants exhibited strong synergy (P <0.05), and the minimum inhibitory concentration (MIC) of ethanolic extracts was also significantly lower than that of the aqueous extract of either plant (P <0.05). In conclusion, the ethanolic extracts of E. globulus and C. procera alone and in combination are effective against MDRSA and can play a role in modulating resistance to beta-lactam antibiotics.

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Ravi, Lokesh, Shabari Girish, M. Harshini et B. K. Anirudh Sreenivas. « β-Sitosterol : An Antibacterial Agent in Aquaculture Management of Vibrio Infections ». Journal of Pure and Applied Microbiology 14, n^o 4 (15 décembre 2020) : 2699–714. http://dx.doi.org/10.22207/jpam.14.4.48.

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This study aims at investigation of antibacterial property of Parthenium hysterophorous against aquatic bacterial pathogens and to identify the key bioactive compound of the same. Antibacterial activity of the crude extracts confirmed that chloroform extract PHC has strong antibacterial activity against aquatic pathogens V.anguillarum and V.harveyi with 16mm and 15mm ZOI at 1mg/well concentration. The crude extracts were subjected for GC-MS analysis to identify the secondary metabolites. PHC was subjected to silica-gel column chromatography to separate the individual phytochemicals. PHC was separated into 9 fractions, among which Fraction No.2 demonstrated significant antibacterial activity against V.anguillarum and V.harveyi with 19mm and 17mm ZOI at 10µg/well concentration. Fraction No.2 was identified to be β-sitosterol based on mass spectrometry analysis and fragmentation analysis. In-silico protein ligand docking demonstrated that β-sitosterol has highest affinity to inhibit dihydrofolate reductase (DHFR) enzyme with -10.10Kcal/mol binding energy. This prediction was further validated using molecular dynamic simulation for 20ns. Based on these computational analyses, it was proposed that β-sitosterol exhibits antibacterial activity via inhibition of DHFR enzyme. β-sitosterol is a well known nutritionally valuable compound that reduces cholesterol levels in humans. It is also been used as supplement feed to increase the nutritional value of cultured fishes. β-sitosterol has also been proven to have positive effect in growth and reproduction of cultivated fishes. Findings of this study strongly suggest the usage of β-sitosterol in aquaculture, as nutritional supplement and also as disease control agent to prevent and control fish diseases caused by Vibrio species.

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Ekhuemelo, D. O., J. V. Anyam et C. Ekhuemelo. « Antimicrobial Efficacy of Vitellaria paradoxa fractions and compounds on some wood Fungi and Bacteria ». Nigerian Journal of Biotechnology 38, n^o 1 (27 juillet 2021) : 1–13. http://dx.doi.org/10.4314/njb.v38i1.1.

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This study examined antifungal efficacy of Vitellaria paradoxa fractions and compounds in the control of some wood degrading fungi. Stem bark and heartwood parts of Vitellaria paradoxa were collected, dried, pulverised and macerated sequentially in n- hexane, methanol and ethyl acetate solvents. The mixtures were filtered, evaporated and the dried samples were mixed and run over silica gel in column chromatography with a mixture of n -hexane and ethyl acetate solvents to obtain fractions. The fractions collected were evaporated and those with white needles were subjected to Magnetic Resonance (NMR) spectroscopic analysis. Spinasterol was isolated and characterised from the heartwood fraction while the stem bark fractions were fatty. Vitellaria paradoxa fractions were active against Serpula lacrymans, Sclerotium rolfsii, Aspergillus fumigatus, Fomitopsis pinicoca, Phaeolus schweinitzii, Rhizopus sp., Coniophora puteana, Gloeophyllum sepiarium, and Fibroporia vaillantii at zones of inhibition (ZOI) of 18 mm - 24 mm. Although the antibiotics were active (25 – 31 mm), they were found inactive against the Fomitopsis pinicoca fungus which was sensitive to all the V. paradoxa fractions at zones of inhibition of 18 - 24 mm. The minimum inhibitory concentrations (MIC) of the V. paradoxa fractions were active at 50 μg/mL against all test fungi. At minimum fungicidal concentration (MFC) of between 50 - 200 μg/mL, all the test fungi were killed. Based on the ZOI, MIC and MFC, the V. paradoxa stem bark heartwood fractions have been proven to be very efficient in inhibiting the growth of test wood rot fungi; hence the species could be explored as a potential source of bioactive fungicides.

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Griseti, Quentin, Christophe Jacquet, Pierre Sautet, Matthew P. Abdel, Sébastien Parratte, Matthieu Ollivier et Jean-Noel Argenson. « Antimicrobial properties of antibiotic-loaded implants ». Bone & ; Joint Journal 102-B, n^o 6_Supple_A (juin 2020) : 158–62. http://dx.doi.org/10.1302/0301-620x.102b6.bjj-2019-1636.r1.

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Aims The aim of this study was to compare the ability of tantalum, 3D porous titanium, antibiotic-loaded bone cement, and smooth titanium alloy to inhibit staphylococci in an in vitro environment, based on the evaluation of the zone of inhibition (ZOI). The hypothesis was that there would be no significant difference in the inhibition of methicillin-sensitive or methicillin-resistant Staphylococcus aureus (MSSA/MRSA) between the two groups. Methods A total of 30 beads made of three different materials (tantalum/3D porous titanium and smooth titanium alloy) were bathed for one hour in a solution of 1 g vancomycin in 20 ml of sterile water for injection (bath concentration: 50 mg/mL). Ten 1 cm3 cylinders of antibiotic-loaded cement were also created by mixing standard surgical cement with 1 g of vancomycin in standardized sterile moulds. The cylinders were then placed on agar plates inoculated with MSSA and MRSA. The ZOIs were measured each day and the cylinders were transferred onto a new inoculated plate. Results For MSSA and MRSA, no inhibitory effect was found in the control group, and antibiotic-loaded smooth titanium alloy beads showed a short inhibitory effect until day 2. For MSSA, both tantalum and 3D porous titanium beads showed significantly larger mean ZOIs than cement beads (all p < 0.01) each day until day 7 for tantalum and until day 3 for 3D porous titanium. After six days, antibiotic-loaded cement had significantly larger mean ZOIs than the 3D porous titanium (p = 0.027), but no significant difference was found with tantalum (p = 0.082). For MRSA, both tantalum and 3D porous titanium beads had significantly larger mean ZOIs than antibiotic-loaded cement each day until day 6 for tantalum (all p < 0.01) and until day 3 for 3D porous titanium (all p < 0.04). Antibiotic-loaded cement had significantly larger mean ZOIs than tantalum and 3D porous titanium from day 7 to 9 (all p < 0.042). Conclusion These results show that porous metal implants can deliver local antibiotics over slightly varying time frames based on in vitro analysis. Cite this article: Bone Joint J 2020;102-B(6 Supple A):158–162.

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Gramlich, Ludwig. « Talidou, Zoi : Regulierte Selbstregulierung im Bereich des Datenschutzes. Europäische Hochschulschriften. Reihe II : Rechtswissenschaft ». Datenschutz und Datensicherheit - DuD 30, n^o 8 (août 2006) : 523–24. http://dx.doi.org/10.1007/s11623-006-0268-1.

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Menon, Soumya, Happy Agarwal, S. Rajesh Kumar et S. Venkat Kumar. « GREEN SYNTHESIS OF SILVER NANOPARTICLES USING MEDICINAL PLANT ACALYPHA INDICA LEAF EXTRACTS AND ITS APPLICATION AS AN ANTIOXIDANT AND ANTIMICROBIAL AGENT AGAINST FOODBORNE PATHOGENS ». International Journal of Applied Pharmaceutics 9, n^o 5 (15 septembre 2017) : 42. http://dx.doi.org/10.22159/ijap.2017v9i5.19464.

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Objective: In the present study, silver (Ag) nanoparticles was synthesized by traditionally used medicinal plant Acalypha indica, which was characterized using various advanced tools, and its antioxidant as well as antimicrobial properties, was studied against food pathogens.Methods: The synthesis of silver (Ag) nanoparticles from the leaf extracts were monitored with the characterization of silver nanoparticles with the help of UV-visible spectrophotometer. The optimized time for the synthesis of nanoparticles was 3 h, followed by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), surface emission microscopy analysis (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and energy dispersive spectroscopy analysis (EDX). The antioxidant activity was evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power assay, while antifungal activity was performed against food pathogens by measuring the zone of inhibition values (ZOI).Results: The Ag nanoparticle produced, have an average particle size of 34 nm with a spherical shape, analyzed from the XRD studies, and size was confirmed with the SEM and TEM analysis. The FTIR analysis gave information about the possible compounds adsorbed on the surface of the Ag nanoparticles. The Ag nanoparticles had good reducing power than the standard and the IC50 value for Ag nanoparticles was 5 mg/ml, while the standard taken had an IC50 value of nearly 6-7 mg/ml. The fungal strain A. fumigates showed ZOI of 133% at 75 µl of concentration proving that Ag nanoparticles can act effectively against this strain when compared to other strains even at low concentrations.Conclusion: The produced Ag nanoparticles can be used for its therapeutic purposes and for large-scale synthesis in food industries for food preservation or packaging.

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Stoodley, Paul, Jacob Brooks, Casey W. Peters, Nan Jiang, Craig P. Delury, Phillip A. Laycock, Sean S. Aiken et Devendra H. Dusane. « Prevention and Killing Efficacy of Carbapenem Resistant Enterobacteriaceae (CRE) and Vancomycin Resistant Enterococci (VRE) Biofilms by Antibiotic-Loaded Calcium Sulfate Beads ». Materials 13, n^o 15 (22 juillet 2020) : 3258. http://dx.doi.org/10.3390/ma13153258.

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Carbapenem-resistant Enterobacteriaceae (CRE) and vancomycin-resistant Enterococci (VRE) have emerged as multidrug-resistant (MDR) pathogens associated with periprosthetic joint infections (PJI). In this study, we evaluated the efficacy of antibiotic-loaded calcium sulfate beads (ALCSB) in inhibiting bacterial growth, encouraging biofilm formation and killing preformed biofilms of CRE and VRE. Three strains of Klebsiella pneumoniae (KP) and a strain of Enterococcus faecalis (EF) were used. ALCSB of 4.8-mm diameter were loaded with vancomycin (V) and gentamicin (G), V and rifampicin (R), V and tobramycin (T) or R and meropenem (M), and placed onto tryptic soy agar (TSA), spread with one of the test strains and incubated for 24 h at 37 °C. Beads were transferred daily onto fresh TSA spread plates and the zone of inhibition (ZOI) was recorded until no inhibition was observed. ALCSB containing R + M or R + V produced the most extensive ZOI up to 5 weeks. Biofilm prevention efficacy was investigated by challenging ALCSB daily with 5 × 105 CFU/mL bacterial cells and analyzing for biofilm formation at challenges 1, 2 and 3. In the biofilm killing experiments, ALCSB were added to pre-grown 3-day biofilms of KP and EF strains, which were then analyzed at days 1 and 3 post-exposure. The CFU counts and confocal images of the attached cells showed that ALCSB treatment reduced colonization and biofilm formation significantly (5–7 logs) with combinations of R + M or R + V, compared to unloaded beads. This study provides evidence that the local release of antibiotics from ALCSB may be useful in treating the biofilms of multidrug-resistant strains of CRE and VRE.

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Shah, Pratibha Jinesh, et Ruchi Malik. « Study of Antibacterial activity of Phyllanthus emblica and its role in Green Synthesis of Silver Nanoparticles ». Journal of Drug Delivery and Therapeutics 9, n^o 3 (5 mai 2019) : 76–81. http://dx.doi.org/10.22270/jddt.v9i3.2753.

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Objective: Phyllanthus emblica L. or amla is known for its therapeutic properties. The aim of the present study was to evaluate the antibacterial activity of aqueous Phyllanthus emblica fruit extract (APE) against eight pathogenic cultures and its application in green synthesis of silver nanoparticles. Methods: APE was screened for the presence of phytochemicals and its antibacterial activity was evaluated by agar well diffusion assay. The minimum inhibitory concentration (MIC) was quantified by broth macrodilution technique, and minimum bactericidal concentration (MBC) was determined. Further, APE was used in the biological synthesis of silver nanoparticles (AgNPs), which were characterized by an Ultraviolet–visible (UV-VIS) spectroscopy and Field emission gun-scanning electron microscopy (FEG-SEM) techniques. The antibacterial activity of the AgNPs was screened by agar well diffusion assay. Results: The zone of inhibition (ZOI) for APE was found to be in the range of 10.7–21.3 mm, for varying concentrations. The MIC values were in the range of 12.5% - 50% (v/v) and the MBC values indicated that a concentration of 50% (v/v) APE could kill 75% (6/8) test cultures. The presence of AgNPs was confirmed by UV-VIS spectroscopy and the surface-plasmon resonance peak was observed at 420 nm. The FEG-SEM analysis revealed that the most of AgNPs were spherical in shape and had 30-40 nm size range. All the test cultures were inhibited by the AgNPs and the average ZOI measured 19.25±2.7 mm. Conclusion: Phyllanthus emblica fruit extract might have therapeutic significance against pathogens and it can be used for green synthesis of silver nanoparticles. Keywords: Phyllanthus emblica, MIC, MBC, silver nanoparticles, UV-VIS, FEG-SEM.

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Ali, Azam, Mariyam Sattar, Fiaz Hussain, Muhammad Humble Khalid Tareen, Jiri Militky et Muhammad Tayyab Noman. « Single-Step Green Synthesis of Highly Concentrated and Stable Colloidal Dispersion of Core-Shell Silver Nanoparticles and Their Antimicrobial and Ultra-High Catalytic Properties ». Nanomaterials 11, n^o 4 (14 avril 2021) : 1007. http://dx.doi.org/10.3390/nano11041007.

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The versatile one-pot green synthesis of a highly concentrated and stable colloidal dispersion of silver nanoparticles (Ag NPs) was carried out using the self-assembled tannic acid without using any other hazardous chemicals. Tannic acid (Plant-based polyphenol) was used as a reducing and stabilizing agent for silver nitrate in a mild alkaline condition. The synthesized Ag NPs were characterized for their concentration, capping, size distribution, and shape. The experimental results confirmed the successful synthesis of nearly spherical and highly concentrated (2281 ppm) Ag NPs, capped with poly-tannic acid (Ag NPs-PTA). The average particle size of Ag NPs-PTA was found to be 9.90 ± 1.60 nm. The colloidal dispersion of synthesized nanoparticles was observed to be stable for more than 15 months in the ambient environment (25 °C, 65% relative humidity). The synthesized AgNPs-PTA showed an effective antimicrobial activity against Staphylococcus Aureus (ZOI 3.0 mM) and Escherichia coli (ZOI 3.5 mM). Ag NPs-PTA also exhibited enhanced catalytic properties. It reduces 4-nitrophenol into 4-aminophenol in the presence of NaBH4 with a normalized rate constant (Knor = K/m) of 615.04 mL·s−1·mg−1. For comparison, bare Ag NPs show catalytic activity with a normalized rate constant of 139.78 mL·s−1·mg−1. Furthermore, AgNPs-PTA were stable for more than 15 months under ambient conditions. The ultra-high catalytic and good antimicrobial properties can be attributed to the fine size and good aqueous stability of Ag NPs-PTA. The unique core-shell structure and ease of synthesis render the synthesized nanoparticles superior to others, with potential for large-scale applications, especially in the field of catalysis and medical.

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