Evaluation of anthropogenic pollution in river water based on the genetic diversity of Aeromonas hydrophila

Abstract Aeromonas hydrophila is a valuable indicator of the quality of water polluted by sewage and pathogens that pose a risk for humans and cold-blooded animals, including fi sh. The main aim of this research was to evaluate anthropogenic pollution of river water based on genetic diversity of 82 A. hydrophila strains by means of RAPD, semi-random AP-PCR (ISJ) and the rep-BOX conservative repeats test. Genetic diversity of A. hydrophila was HT = 0.28 (SD = 0.02) for all DNA markers (RAPD, semi random and rep-BOX). None of the analyzed electrophoretic patterns was identical, implying that there were many sources of strain transmission. The presence of genes for aerolysin (aerA), hemolysin (ahh1) and the cytotoxic enzyme complex (AHCYTOGEN) was verifi ed for all tested strains, and drug resistance patterns for tetracycline, enrofl oxacin and erythromycin were determined. The most diverse A. hydrophila strains isolated from river water were susceptible to enrofl oxacine (HS = 0.27), whereas less diverse strains were susceptible to erythromycin (HS = 0.24). The presence of the multidrug resistance marker (ISJ4-25; 1100 bp locus) in the examined strains (resistant to three analyzed drugs) indicates that intensive fi sh cultivation affects the microbiological quality of river water.

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Are the defined substrate-based methods adequate to determine the microbiological quality of natural recreational waters?

Journal of Water and Health ◽

10.2166/wh.2009.220 ◽

2009 ◽

Vol 8 (1) ◽

pp. 11-19 ◽

Cited By ~ 6

Author(s):

Marta Sofia Valente ◽

Paulo Pedro ◽

M. Carmen Alonso ◽

Juan J. Borrego ◽

Lídia Dionísio

Keyword(s):

Standard Method ◽

Membrane Filtration ◽

Microbiological Quality ◽

Recreational Waters ◽

Total Coliforms ◽

E Coli ◽

Quality Of Water ◽

Routine Monitoring ◽

Rapid Tests

Monitoring the microbiological quality of water used for recreational activities is very important to human public health. Although the sanitary quality of recreational marine waters could be evaluated by standard methods, they are time-consuming and need confirmation. For these reasons, faster and more sensitive methods, such as the defined substrate-based technology, have been developed. In the present work, we have compared the standard method of membrane filtration using Tergitol-TTC agar for total coliforms and Escherichia coli, and Slanetz and Bartley agar for enterococci, and the IDEXX defined substrate technology for these faecal pollution indicators to determine the microbiological quality of natural recreational waters. ISO 17994:2004 standard was used to compare these methods. The IDEXX for total coliforms and E. coli, Colilert®, showed higher values than those obtained by the standard method. Enterolert® test, for the enumeration of enterococci, showed lower values when compared with the standard method. It may be concluded that more studies to evaluate the precision and accuracy of the rapid tests are required in order to apply them for routine monitoring of marine and freshwater recreational bathing areas. The main advantages of these methods are that they are more specific, feasible and simpler than the standard methodology.

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Study of the Microbial Ecology of Wild and Aquacultured Tunisian Fresh Fish

Journal of Food Protection ◽

10.4315/0362-028x.jfp-11-057 ◽

2011 ◽

Vol 74 (10) ◽

pp. 1762-1768 ◽

Cited By ~ 15

Author(s):

MOUNA BOULARES ◽

LOBNA MEJRI ◽

MNASSER HASSOUNA

Keyword(s):

Aeromonas Hydrophila ◽

Microbiological Quality ◽

Common Species ◽

Microbial Populations ◽

Plate Count ◽

Gram Negative Bacteria ◽

Fresh Fish ◽

Psychrotrophic Bacteria ◽

Aerobic Plate Count

Eighty samples of fresh fish were collected in Tunisia and analyzed for microbial load. Quality and hygienic safety of the meat and intestines of wild and aquacultured fresh fish were determined. The mesophilic aerobic plate count and populations of psychrotrophic lactic acid bacteria (LAB) and other psychrotrophic bacteria ranged from 5.67 to 7.29, 4.51 to 6, and 5.07 to 6.21 log CFU/g, respectively. For all microbiological determinations, bacterial counts were lower in meat than in the intestines of fresh fish. For all samples lower microbial populations were found in most of the wild fish than in the aquacultured fish. No isolates of the pathogenic genera Salmonella and Listeria were detected in any sample. Among the 160 strains of biopreservative psychrotrophic LAB and the 150 strains of spoilage psychrotrophic gram-negative bacteria identified by biochemical and molecular methods, Lactobacillus (six species) and Pseudomonas (six species) predominated. Lactococcus, Leuconostoc, Carnobacterium (C. piscicola and C. divergens), Aeromonas, and Photobacterium were the most common genera, and Lactococcus lactis, Lactobacillus plantarum, Pseudomonas fluorescens, and Aeromonas hydrophila were the most common species. These findings indicate that the microbiological quality of fresh fish in Tunisia can be preserved by controlling pathogenic and psychrotrophic bacteria.

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Microbiological quality of water from noncommunity supply wells in carbonate and crystalline aquifers of Pennsylvania

10.3133/wri014268 ◽

2002 ◽

Cited By ~ 1

Keyword(s):

Microbiological Quality ◽

Quality Of Water

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THE MICROBIOLOGICAL QUALITY OF WATER, PATHOGENIC MICROORGANISMS IN FOOD PRODUCTS AND FACEL CONTAMINATION IN THE RIVERS OF THE REPUBLIC OF KOSOVO

RASAYAN Journal of Chemistry ◽

10.31788/rjc.2018.1144065 ◽

2018 ◽

Vol 11 (4) ◽

pp. 1399-1404

Author(s):

Nexhdet Shala ◽

Ibrahim Hoxha ◽

Gafur Q. Xhabiri ◽

Bajram Avdiu

Keyword(s):

Microbiological Quality ◽

Food Products ◽

Pathogenic Microorganisms ◽

Quality Of Water ◽

The Republic

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Microbiological Quality of Water

MWH's Water Treatment ◽

10.1002/9781118131473.ch3 ◽

2012 ◽

pp. 73-164

Keyword(s):

Microbiological Quality ◽

Quality Of Water

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The pursuit of good microbiological conditions in domestic softeners: a new improvement

Journal of Water and Health ◽

10.2166/wh.2020.136 ◽

2020 ◽

Vol 18 (2) ◽

pp. 200-206

Author(s):

L. Bolelli ◽

Elida Nora Ferri ◽

Stefano Sangiorgi ◽

Giuseppe Novelli ◽

Stefano Girotti

Keyword(s):

Pathogenic Bacteria ◽

Microbiological Quality ◽

Global Network ◽

Plate Count ◽

Bacteria Growth ◽

Warm Environment ◽

Quality Of Water ◽

Softened Water ◽

Generous Support

Abstract Effective resin disinfection is mandatory to ensure the microbiological quality of water treated by domestic softeners. The wet and sometimes warm environment inside the softener is ideal for bacteria growth. Our research was focused on the evaluation of the microbial quality of water from softeners sanitized by chlorine solutions or by electrolytic systems. We employed the heterotrophic plate count and specific tests to monitor the presence of opportunistic and pathogenic bacteria (Pseudomonas aeruginosa, Escherichia coli, enterococci, and coliforms). Completely new devices were equipped with a commercially available electrolytic system or with a newly patented one or sanitized by automatic or manual addition of chlorine solutions. In all cases, the contamination was reduced, not completely avoided. In particular, the patented electrolytic system significantly reduced bacterial proliferation in strongly contaminated devices. Our data confirm the difficulties encountered to solve the problem of microbiological quality of softened water and offer encouraging information on new possible solutions. This article has been made Open Access thanks to the generous support of a global network of libraries as part of the Knowledge Unlatched Select initiative.

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