1,720,987 research outputs found
Viral Indicators of Hygienic-Sanitary Quality: Detection of Somatic Coliphages in the Southern Adriatic Sea.
No full textRotavirus detection in environmental water samples by tangential flow ultrafiltration and RT-nested PCR
No full textEnvironmental monitoring was conducted in Otranto (Italy), from January 2006 to April 2007, to monitor the circulation of rotaviruses in various water matrices (raw and treated sewage, surface waters and seawater) and to identify any correlation with the traditional bacteriological indices (faecal coliforms). The viruses were detected using tangential flow ultrafiltration and reverse transcriptase-nested polymerase chain reaction, whilst detection of feaecal coliform was performed according to standard methods. The results showed widespread viral contamination, particularly in spring, of the matrices tested, with the exception of seawater, which at all times tested negative for the presence of rotaviruses. The typing of the rotavirus strains identified the circulation in the studied area of only two genotypes: G1 (22%) and G2 (78%). The bacterial recoveries confirmed the presence of faecal pollution indicators in all examined samples, sometimes with high values. A very weak correlation was found between the presence of faecal coliforms and the circulation of rotaviruses in the environment. The presence of rotaviruses in the environmental water samples may constitute a potential health risk for the local population. © 2009 Springer Science+Business Media B.V
Study of the correlation between microfauna and the macrostructure of activated sludge and the efficiency of biological wastewater treatment plants
No full textAssessment of protozoan populations is an important tool in
evaluating the efficiency of activated sludge in the treatment of
wastewater. In this process, protozoa play a significant role by
grazing on dispersed bacteria, supporting a healthy food web
in activated sludge artificial ecosystems. The objective of this
study was to verify how the success of the purification process in
activated sludge plants, mainly in terms of TSS, BOD5 and COD,
is related to ciliate protozoa communities and the presence of
filamentous bacteria.
Samples were collected from five water treatment plants in the
Puglia region, in the period May 2007 - April 2008. Microfauna
and filamentous bacteria were identified and quantified, and the
sludge biotic index calculated.
The data show a correlation between the biological components
of activated sludge and traditional chemical parameters. Our
results indicate that biological analyses represent a valid alternative
to traditional chemical testing in assessing the performance
of activated sludge systems
Environmental circulation of rotaviruses: use of mussel as natural accumulation matrices in coastal seawaters
No full textListeria Species in campioni di origine alimentare: influenza della temperatura nelle tecniche di isolamento
No full textMicrobial and nutritional aspects on the production of live feeds in a fish farming industry
No full textAquaculture is an enterprise in constant development, in particular relating to its effect on the environment and also the quality of its products. It represents a valid alternative to traditional fishing, facing the increasing demand for fish products. To guarantee to the consumer a product of high nutritional, organoleptic and hygienic quality, it is fundamental to monitor every phase of the fish farming industry, isolating the potential risk points. For this reason there has been a rapid evolution of productive technique, particularly in the technology, artificial reproduction and feed sectors. The aim of this research has been the monitoring of the evolution of certain microbial and nutritional quality indexes (total microbial counts and lipid analysis on suspensions of Rotifers and Artemia, used as live feed) in the larval phase of the productive cycle of the farm raised fish, in an intensive system. The study has shown an increment in the total microbial counts in the fish farming industry within the production of Rotifers and Artemia, more evident in the suspensions of Rotifers. In addition the study has demonstrated that the maintenance phase, in the enrichment protocol, can reduce the EPA and DHA content. The results confirm the importance of microbial and nutritional control of the live feeds before they get supplied to fish larvae
Valutazione dello stato di qualità delle acque marine costiere del Salento sud- orientale
No full textLe aree marine costiere sono ecosistemi caratterizzati da elevata diversità e produttività biologica. La conservazione dell’integrità di questi ambienti e dei loro equilibri interni sono obiettivi prioritari di tutte le politiche di sviluppo sociale ed economico di ogni paese.
Il presente studio ha avuto come obiettivo l’identificazione dei fattori potenzialmente responsabili dell’alterazione della qualità ecologica delle acque marine costiere lungo il litorale del Salento sud-orientale, nell’area Parco di Otranto-Santa Maria di Leuca. Per lo studio delle relazioni causa-effetto è stato applicato il modello concettuale DPSIR, utilizzando un set di indicatori – determinanti, pressioni, stato, impatti e riposte - utili alla gestione delle acque costiere. Tra i DETERMINANTI sono stati considerati gli aspetti demografici, sociali ed economici. Le dinamiche di sfruttamento ambientale e di produzione di carichi inquinanti sono state considerate indicatori di PRESSIONE. Per la valutazione dello STATO di salute dell’ecosistema considerato, sono stati monitorati parametri chimico-fisici (azoto e fosforo totali, ossigeno disciolto, temperatura, salinità e pH), microbiologici (Escherichia coli, batteri eterotrofi totali e relativa frazione luminescente) ed ecologici (Clorofilla a e TRIX). Le RISPOSTE sono state valutate attraverso le azioni di tutela ambientale implementate sul territorio studiato. I risultati hanno evidenziato la presenza di una forte pressione antropica, legata essenzialmente alle attività turistiche e allo smaltimento non idoneo di reflui provenienti dalle aree urbanizzate.
Lo stato di salute delle acque costiere è risultato entro i limiti delle normative vigenti, sia facendo riferimento ai valori degli indicatori fecali che all’Indice trofico TRIX. Si sono però osservate aree interessate a fenomeni di maggiore contaminazione, in prossimità delle risorgive.
Ciò evidenzia un inquinamento proveniente da sorgenti diffuse che impone il problema di una gestione più attenta ed articolata dell’intero litorale, al fine di ridurre le pressioni e gli impatti derivanti dallo sfruttamento incontrollato della fascia costiera
Phenotypic characterization of culturable marine luminous bacteria isolated from coastal waters of the southern Adriatic Sea (Otranto, Italy).
No full textTo determine the abundance and species composition of luminous bacteria in the coastal waters of the southern Adriatic Sea (Otranto, Italy), samples were collected from three sites affected by different degrees of anthropogenic pollution. A total of 116 strains of marine luminous bacteria were isolated and subjected to phenotypic characterization, which included 36 biochemical tests. Numerical analysis of the data revealed five clusters with > 86% similarity, which were readily identified as Photobacterium leiognathi, Vibrio fischeri, Vibrio harveyi, Vibrio splendidus biovar I, and Shewanella hanedai. The relative abundance of each species shows that culturable luminous bacteria in the monitored waters are composed mainly of V. harveyi (69.0%), followed by V. fischeri (13.8%) and P. leiognathi (12.1%). In addition, human activity appears to affect the total abundance of luminous bacteria but not the selection of individual species, since the frequencies of the bacteria were similar at all examined sites
Phenotypic characterization of culturable marine luminous bacteria isolated from coastal waters of the southern Adriatic sea (Otranto, Italy)
No full textTo determine the abundance and species composition of luminous bacteria in the coastal waters of the southern Adriatic Sea (Otranto, Italy), samples were collected from three sites affected by different degrees of anthropogenic pollution. A total of 116 strains of marine luminous bacteria were isolated and subjected to phenotypic characterization, which included 36 biochemical tests. Numerical analysis of the data revealed five clusters with > 86% similarity, which were readily identified as Photobacterium leiognathi, Vibrio fischeri, Vibrio harveyi, Vibrio splendidus biovar I, and Shewanella hanedai. The relative abundance of each species shows that culturable luminous bacteria in the monitored waters are composed mainly of V. harveyi (69.0%), followed by V. fischeri (13.8%) and P. leiognathi (12.1%). In addition, human activity appears to affect the total abundance of luminous bacteria but not the selection of individual species, since the frequencies of the bacteria were similar at all examined sites
Fruibilità di risorse idriche pregiate nel territorio afferente all'Unione dei Comuni"Terre D'Oriente" nel Sud-Salento.
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