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641.
Lixandru BE Drăcea NO Dragomirescu CC Drăgulescu EC Coldea IL Anton L Dobre E Rovinaru C Codiţă I 《Roumanian archives of microbiology and immunology》2010,69(4):224-230
The currative properties of aromatic and medicinal plants have been recognized since ancient times and, more recently, the antimicrobial activity of plant essential oils has been used in several applications, including food preservation. The purpose of this study was to create directly comparable, quantitative data on the antimicrobial activity of some plant essential oils prepared in the National Institute of Research-Development for Chemistry and Petrochemistry, Bucharest to be used for the further development of food packaging technology, based on their antibacterial and antifungal activity. The essential oils extracted from thyme (Thymus vulgaris L.), basil (Ocimum basilicum L.), coriander (Coriandrum sativum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), fennel (Foeniculum vulgare L.), spearmint (Mentha spicata L.) and carraway (Carum carvi L.) were investigated for their antimicrobial activity against eleven different bacterial and three fungal strains belonging to species reported to be involved in food poisoning and/or food decay: S. aureus ATCC 25923, S. aureus ATCC 6538, S. aureus ATCC 25913, E. coli ATCC 25922, E. coli ATCC 35218, Salmonella enterica serovar Enteritidis Cantacuzino Institute Culture Collection (CICC) 10878, Listeria monocytogenes ATCC 19112, Bacillus cereus CIP 5127, Bacillus cereus ATCC 11778, Candida albicans ATCC 10231, Aspergillus niger ATCC 16404, Penicillium spp. CICC 251 and two E. coli and Salmonella enterica serovar Enteritidis clinical isolates. The majority of the tested essential oils exibited considerable inhibitory capacity against all the organisms tested, as supported by growth inhibition zone diameters, MICs and MBC's. Thyme, coriander and basil oils proved the best antibacterial activity, while thyme and spearmint oils better inhibited the fungal species. 相似文献
642.
Maxime Boutier Maygane Ronsmans Ping Ouyang Guillaume Fournier Anca Reschner Krzysztof Rakus Gavin S. Wilkie Frédéric Farnir Calixte Bayrou Fran?ois Lieffrig Hong Li Daniel Desmecht Andrew J. Davison Alain Vanderplasschen 《PLoS pathogens》2015,11(2)
Cyprinid herpesvirus 3 (CyHV-3) is causing severe economic losses worldwide in common and koi carp industries, and a safe and efficacious attenuated vaccine compatible with mass vaccination is needed. We produced single deleted recombinants using prokaryotic mutagenesis. When producing a recombinant lacking open reading frame 134 (ORF134), we unexpectedly obtained a clone with additional deletion of ORF56 and ORF57. This triple deleted recombinant replicated efficiently in vitro and expressed an in vivo safety/efficacy profile compatible with use as an attenuated vaccine. To determine the role of the double ORF56-57 deletion in the phenotype and to improve further the quality of the vaccine candidate, a series of deleted recombinants was produced and tested in vivo. These experiments led to the selection of a double deleted recombinant lacking ORF56 and ORF57 as a vaccine candidate. The safety and efficacy of this strain were studied using an in vivo bioluminescent imaging system (IVIS), qPCR, and histopathological examination, which demonstrated that it enters fish via skin infection similar to the wild type strain. However, compared to the parental wild type strain, the vaccine candidate replicated at lower levels and spread less efficiently to secondary sites of infection. Transmission experiments allowing water contamination with or without additional physical contact between fish demonstrated that the vaccine candidate has a reduced ability to spread from vaccinated fish to naïve sentinel cohabitants. Finally, IVIS analyses demonstrated that the vaccine candidate induces a protective mucosal immune response at the portal of entry. Thus, the present study is the first to report the rational development of a recombinant attenuated vaccine against CyHV-3 for mass vaccination of carp. We also demonstrated the relevance of the CyHV-3 carp model for studying alloherpesvirus transmission and mucosal immunity in teleost skin. 相似文献
643.
Simona Savin Oana Craciunescu Anca Oancea Daniela Ilie Teodora Ciucan Loredana Stefania Antohi Agnes Toma Alina Nicolescu Calin Deleanu Florin Oancea 《化学与生物多样性》2020,17(7)
Two chitosan extracts were prepared by chemical and enzymatic treatment of Ganoderma lucidum mushroom, as an alternative source to crustacean shells. The molecular weight of the enzymatic extract was lower than that of the chemical one and of shrimp chitosan, as determined by viscosity measurements. Characteristic signals were identified in the 1H‐NMR spectra and high deacetylation degree indicated good physico‐chemical properties for both mushroom chitosan extracts. The scavenging capacity of mushroom chitosan extracts was moderate against the synthetic radicals of 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), but higher values were observed for the enzymatic extract, compared to the chemical extract and shrimp chitosan. In vitro cytotoxicity was evaluated in L929 mouse fibroblast cell lines and the results of MTT assay showed good cytocompatibility in the tested range of concentrations. The growth of Gram‐positive bacteria was inhibited more than Gram‐negative bacteria in the presence of mushroom chitosan extracts, in particular by the chemical one, indicating their efficiency as antimicrobial agents. All these results strengthen the evidence of mushroom polysaccharide preparations availability for biomedical applications. 相似文献
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645.
Bujor Alexandra Miron Anca Trifan Adriana Luca Simon Vlad Gille Elvira Miron Sorin-Dan Aprotosoaie Ana Clara 《Phytochemistry Reviews》2021,20(4):653-691
Phytochemistry Reviews - Endothelial dysfunction (impaired vasodilation, prothrombotic, proinflammatory and prooxidant states) is involved in the development of cardiovascular diseases... 相似文献
646.
The relationship between algae and depositional environment was studied in a limestone succession of Berriasian–Valanginian age. Several depositional environments were recorded from shallow subtidal to intertidal and supratidal, with salinity ranging from normal marine to fresh and/or supersaline water. The algal assemblages consist mainly of dasycladaleans, rivulariacean-type cyanobacteria and charophytes. Nipponophycus (Bryopsydales) and Lithocodium-Bacinella (microproblematicum), occur at some levels. Dasycladaleans are associated with subtidal, sometimes restricted (“lagoonal”) environments, while rivulariacean-like cyanobacteria and charophytes characterise intertidal-supratidal and fresh and/or supersaline environments, respectively. Among the dasycladaleans, Salpingoporella annulata is often related to restricted environments where it forms monospecific assemblages. Large dasycladaleans, such as Selliporella neocomiensis, Macroporella praturloni and Pseudocymopolia jurassica are found in subtidal high-energy deposits (bioclastic grainstones). The relationship between environment and algae, characteristic for each depositional unit, can be used to interpret the relative sea-level variations. 相似文献
647.
Summary In Perilla ocymoides, a daily lengthening by 20 min of the photoperiod in the non-inductive day length and, at the end of the treatment, a sudden change from a continuous day to a short day or the exposition of one pair of leaves to shortday conditions and another pair one node higher to continuous light induces teratological modifications. 相似文献
648.
In a cross-sectional study of steelworkers aged 45-55 years, smokers (n = 105; mean weight 76.1 kg) were found to weigh significantly less than non-smokers (n = 54; 81.6 kg) and ex-smokers (n = 51; 82.6 kg). The lower weight of smokers was attributable to a group with airflow obstruction (n = 37; forced expiratory volume in one second/vital capacity (FEV1/VC) less than 66%), who weighed less (4.8 kg; p less than 0.05) than smokers with normal FEV1/VC (n = 68). In smokers, but not in ex-smokers or non-smokers, body mass index and FEV1/VC ratio were closely related (r = 0.34; p less than 0.001). This association was apparently not due to an effect of body weight on lung function. Weight loss in smokers may be the consequence of impaired lung function or reflect the effect of cigarette smoking on both the respiratory tract and metabolism in susceptible subjects. 相似文献
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