Search results for "Aeromonas"
showing 10 items of 33 documents
Preliminary Study on the In vitro and In vivo Effects of Asparagopsis taxiformis Bioactive Phycoderivates on Teleosts
2016
Several compounds from marine organisms have been studied for their potential use in aquaculture. Among the red algae, Asparagopsis taxiformis is considered one of the most promising species for the production of bioactive metabolites with numerous proposed applications. Here, the in vitro antibacterial activity, the easy handling and the absence of adverse effects on marine fish species are reported. Depending on the seasonal period of sampling, ethanol extracts of A. taxiformis exhibited significantly different inhibitory activity against fish pathogenic bacteria. The extract obtained in late spring showed strong antibacterial activity against Aeromonas salmonicida subsp. salmonicida, Vib…
First data on microflora of loggerhead sea turtle (Caretta caretta) nests from the coastlines of Sicily (Italy)
2020
ABSTRACT Caretta caretta is threatened by many dangers in the Mediterranean basin, but most are human-related. The purposes of this research were: (i) to investigate microflora in samples from six loggerhead sea turtle nests located on the Sicilian coast and (ii) to understand microbial diversity associated with nests, with particular attention to bacteria and fungi involved in failed hatchings. During the 2016 and 2018 summers, 456 eggs and seven dead hatchling from six nests were collected. We performed bacteriological and mycological analyses on 88 egg samples and seven dead hatchlings, allowing us to isolate: Fusarium spp. (80.6%), Aeromonas hydrophila (55.6%), Aspergillus spp. (27.2%) …
The antioxidant power of horseradish, Armoracia rusticana, underlies antimicrobial and antiradical effects, exerted in vitro
2018
Armoracia rusticana (AR) was tested for antimicrobial and antioxidants power. The compound demonstrated to inhibit fish pathogens such as Vibrio anguillarum, V. harvey, V. alginolyticus, Aeromonas hydrophila, A. salmonicida, Photobacterium damselae subspecie piscicida, Tenacibaculum marinum and Pseudomonas anguilliseptica,. The total phenolic content and the reducing power resulted higher in the water extract of AR, respect to the hydroalcoolic. In vitro test demonstrated that AR significantly protect cells against death, induced by oxidative stress.
Is Caretta Caretta a Carrier of Antibiotic Resistance in the Mediterranean Sea?
2020
Sea turtles can be considered a sentinel species for monitoring the health of marine ecosystems, acting, at the same time, as a carrier of microorganisms. Indeed, sea turtles can acquire the microbiota from their reproductive sites and feeding, contributing to the diffusion of antibiotic-resistant strains to uncontaminated environments. This study aims to unveil the presence of antibiotic-resistant bacteria in (i) loggerhead sea turtles stranded along the coast of Sicily (Mediterranean Sea), (ii) unhatched and/or hatched eggs, (iii) sand from the turtles&rsquo
Inhibited fatty acid β-oxidation impairs stress resistance ability in Nile tilapia (Oreochromis niloticus)
2017
Energy metabolism plays important roles in stress resistance and immunity in mammals, however, such functions have not been established in fish. In the present study, Nile tilapia (Oreochromis niloticus) was fed with mildronate, an inhibitor of mitochondrial fatty acid (FA) β-oxidation, for six weeks subsequently challenged with Aeromonas hydrophila and ammonia nitrogen exposure. Mildronate treatment reduced significantly l-carnitine concentration and mitochondrial FA β-oxidation efficiency, while it increased lipid accumulation in liver. The fish with inhibited hepatic FA catabolism had lower survival rate when exposed to Aeromonas hydrophila and ammonia nitrogen. Moreover, fish fed mildro…
Seasonal recovery ofEdwardsiella piscicidafrom wild European eels and natural waters: Isolation methods, virulence and reservoirs
2018
A total of 127 wild eels caught in the L'Albufera Lake (Spain) and 24 samples of lagoon freshwater were analysed for 1-year period. Edwardsiella strains were isolated from liver/kidney on TSA-1 plates in 31.9% of total diseased specimens, and the edwardsiellosis prevalence in the fishery was of 11.8%. The use of double-strength Salmonella-Shigella (DSSS) broth and SS agar yielded Edwardsiella isolation from intestine in 100% of those edwardsiellosis-diseased eels, but also in 40.4% of other sick fish with vibriosis or aeromonosis and in 28.8% of healthy eels, as well as from freshwater in 8.3% of samples. Pure cultures were isolated on SS agar from the former, but motile Aeromonas, Plesiomo…
Pathogenic Aeromonas hydrophila Serogroup O:14 and O:81 Strains with an S Layer
2004
ABSTRACT Five autoagglutinating Aeromonas hydrophila isolates recovered from eels and humans were assigned to serogroups O:14 and O:81 of the Sakazaki and Shimada (National Institutes of Health) scheme. They had the following properties in common: positive precipitation after boiling, moderate surface hydrophobicity (salt-aggregation-test value around 1.2), pathogenicity for fish and mice (50% lethal dose, 10 4.61 to 10 7.11 ), lipopolysaccharides that contained O-polysaccharide chains of homogeneous chain length, and an external S layer peripheral to the cell wall observed by electron microscopy. A strong cross-reactivity was detected by immunoblotting between the homogeneous O-polysacchar…
Bacterial Community Structure of an IFAS-MBRs Wastewater Treatment Plant
2017
TIn this work, the bacterial community putatively involved in BNR events of a UCT-MBMBR pilot plant was elucidated by both culture-dependent and metagenomics DNA analyses. The presence of bacterial isolates belonging to Bacillus (in the anoxic compartment) and to Acinetobacter, Stenotrophomonas, Rhodococcus, Escherichia and Aeromonas (in the aerobic compartment) is in agreement with the nitrification/denitrification processes observed in the plant. Moreover, the study of bacterial community structure by NGS revealed a microbial diversity suggesting a biochemical complexity which can be further explored and exploited to improve UCT-MBMBR plant performance.
Mechanisms of quinolone resistance in Aeromonas species isolated from humans, water and eels.
2009
Mechanisms of resistance were determined in 33 quinolone-resistant isolates of the species Aeromonas hydrophila, Aeromonas caviae, Aeromonas media, Aeromonas salmonicida, Aeromonas popoffii and Aeromonas veronii, recovered from humans, freshwater and eels. The quinolone resistance-determining regions (QRDRs) of gyrA and parC genes were sequenced in these resistant strains, as well as in 8 quinolone-sensitive Aeromonas used as controls. All quinolone-resistant Aeromonas carried point mutations in the gyrA QRDR at codon 83, respectively giving rise to substitutions Ser(83)-->Ile (32 strains) or Ser(83)-->Val (1 strain). Almost half of these isolates (48%) carried additional point mutations in…
Taxonomic study of sucrose-positive Aeromonas jandaei-like isolates from faeces, water and eels: emendation of A. jandaei Carnahan et al. 1992
2003
Fourteen sucrose-positive Aeromonas jandaei-like isolates from fresh water and reared European eels were subjected to a polyphasic study to determine their taxonomic position. Numerical taxonomy was used to analyse phenotypic data obtained for these isolates and 43 type and reference strains representative of recognized Aeromonas species. The A. jandaei cluster (phenon 1) was defined at 81.6 % similarity (S(J)); this included the A. jandaei-like isolates, the sucrose-positive strain Aeromonas veronii biogroup sobria CECT 4910 and nearly all A. jandaei reference strains used in the study. Four other reference strains of A. veronii biogroup sobria and the type strain of Aeromonas ichthiosmia …