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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

HUMAN AND ANIMAL HEALTH RISK ASSESSMENT OF MYCOTOXIN MIXTURES IN MAIZE: FROM FUNGAL PRODUCTION AND OCCURRENCE TO HARMONISED RISK CHARACTERISATION

PALUMBO, ROBERTA 03 April 2020 (has links)
Maize is the principal staple food/feed crop exposed to mycotoxins, and the co-occurrence of multiple mycotoxins and their metabolites has been well documented. Dietary (co)-exposure to mycotoxins is associated with human and animal health concerns as well as economic losses. The present thesis aims to apply a holistic approach for the risk assessment of mycotoxin mixtures in food and feed, i.e. from fungal production and occurrence to harmonised risk characterisation. This was done in three folds. Firstly, available environmental, ecological, and agronomic factors that may affect the relative abundance of co-occurring mycotoxins in the contaminated crops were collected from peer-reviewed literature, with focus on maize (Chapter I). Secondly, (co-)occurrence data on mycotoxins in core cereals was extracted from available articles in the scientific literature and analysed to estimate potential pattern of co-exposure in humans and animals (Chapter II). Finally, Chapter III investigates the applicability of the EFSA guidance to multiple mycotoxins through a scenario of possible co-exposure in humans and animals, using maize as a case study. In particular, a human and animal risk assessment to mycotoxin mixture in maize was conducted using a modelled component-based approach for selected mixture of mycotoxins, that, according to our data, co-occur in maize based feed and food products. / Maize is the principal staple food/feed crop exposed to mycotoxins, and the co-occurrence of multiple mycotoxins and their metabolites has been well documented. Dietary (co)-exposure to mycotoxins is associated with human and animal health concerns as well as economic losses. The present thesis aims to apply a holistic approach for the risk assessment of mycotoxin mixtures in food and feed, i.e. from fungal production and occurrence to harmonised risk characterisation. This was done in three folds. Firstly, available environmental, ecological, and agronomic factors that may affect the relative abundance of co-occurring mycotoxins in the contaminated crops were collected from peer-reviewed literature, with focus on maize (Chapter I). Secondly, (co-)occurrence data on mycotoxins in core cereals was extracted from available articles in the scientific literature and analysed to estimate potential pattern of co-exposure in humans and animals (Chapter II). Finally, Chapter III investigates the applicability of the EFSA guidance to multiple mycotoxins through a scenario of possible co-exposure in humans and animals, using maize as a case study. In particular, a human and animal risk assessment to mycotoxin mixture in maize was conducted using a modelled component-based approach for selected mixture of mycotoxins, that, according to our data, co-occur in maize based feed and food products.
32

Dai mangimi al latte: fattori di rischio e qualità / FEED INTO MILK: QUALITY AND RISK FACTORS

BATTAGLIA, MARCO 22 April 2010 (has links)
La tesi è divisa in quattro manoscritti. Lo scopo è lo studio di tre aspetti, come casi-studio indipendenti, all’interno della gestione della catena alimentare dai mangimi al latte. Il primo manoscritto riguarda la fortificazione del latte bovino con iodio e selenio allo scopo di migliorare la qualità del latte e dei suoi derivati; il secondo riguarda la contaminzione dei mangimi con melamina come fattore di rischio per l’industria lattiero-casearia e la salute pubblica. Gli ultimi due lavori sono corollari alla qualità del latte derivante dallo iodio: ovvero un confronto analitico tra procedure di determinazione dello iodio in latte crudo, e uno studio di speciazione dello iodio inorganico nel latte crudo fortificato. Il primo lavoro offre informazioni per meglio comprendere i fattori coinvolti nel miglioramento della concentrazione dello iodio e del selenio nel latte a seguito di una fortificazione della dieta animale. Riguardo la melamina, lo studio conferma il passaggio di essa dai mangimi al latte e la sua rapida escrezione anche a livelli bassi di ingestione da parte dell’animale; uno scarso passaggio dal latte al formaggio. Il terzo lavoro mostra che, per analisi dello iodio con ICP-MS, l’estrazione dell’elemento con soluzione d’ammoniaca è una valida alternativa al metodo ufficiale con TMAH. La speciazione dello iodio inorganico nel latte scremato è un’operazione possibile utilizzando delle diluizioni con soluzione d’ammoniaca (quarto manoscritto). / The thesis is divided into 4 manuscripts. The aim is to study three aspects, as independent case studies, within the quality management of feed-for-food system. The first manuscript is about the fortification of feeds with iodine and selenium to improve the quality of cow’s milk and derivatives; the second one investigates the contamination of feeds with melamine as risk factor for dairy industries and human health. The last two works are corollaries to the iodine-linked quality of milk: i.e. a comparison between analytical procedures for the determination of iodine in raw milk, and a speciation study of iodine in fortified milk. The first work helps to better understand factors involved in improvement of milk iodine and selenium concentration and CO following supplementation with inorganic sources. Regarding melamine, the study confirmed the pathway for its transmission from feed to milk and its rapid excretion, also at a very low level of melamine ingestion by cows; and a low transfer from milk to cheese. The third study shows that the ammonia extraction of iodine is a valid alternative to the official method with TMAH for iodine determination in milk, by using ICP-MS. The speciation of inorganic iodine in skimmed milk is feasible by using ammonia dilution (fourth manuscript).
33

VALUTAZIONE E MIGLIORAMENTO DELLO STATO NUTRIZIONALE DELLE POPOLAZIONI IN DIVERSE CONDIZIONI PEDOCLIMATICHE E SOCIOECONOMICHE / ASSESSMENT AND IMPROVEMENT OF NUTRITIONAL STATUS OF POPULATION IN DIFFERENTS PEDOCLIMATIC AND SOCIO-ECONOMIC CONDITIONS / ASSESSMENT AND IMPROVEMENT OF NUTRITIONAL STATUS OF POPULATIONS IN DIFFERENT PEDOCLIMATIC AND SOCIO-ECONOMIC CONDITIONS

NDEREYIMANA, ANDRE 14 December 2017 (has links)
La dieta, lo stato nutrizionale e la salute sono questioni strettamente correlate sia nei paesi industrializzati che in quelli in via di sviluppo. In questa tesi di dottorato, l'obiettivo principale è stato quello di valutare lo stato nutrizionale come passo prodromico per migliorarlo per ottimizzare la salute. Nei paesi industrializzati è stato condotto un caso studio sullo stato nutrizionale di una popolazione dell'Italia centrale; l’ingestione di alcuni gruppi di alimenti, di origine animale e vegetale, è stata valutata mediante questionari di frequenza alimentare e alcuni biomarcatori del sangue. I risultati hanno dimostrato che nei controlli della dieta, al fine di accertarne gli effetti a lungo termine sulla salute, le misurazioni dei consumi tramite questionari non possono essere esclusive, ma alcuni indici ematici ed antropometrici potrebbero essere utili. Nei paesi in via di sviluppo, due casi di studio in zone rurali dell’India e della Repubblica Democratica del Congo hanno confermato che la malnutrizione è un problema serio; in particolare nei bambini di 3-5 anni con il 26% di malnutrizione cronica severa in India e oltre il 60% in R D Congo. Possibili percorsi per migliorare le condizioni di vita delle comunità rurali povere includono la produzione di cibi appropriati per una dieta migliore, nuove attività generatrici di reddito, miglioramento della nutrizione infantile, riduzione delle malattie causate dalla contaminazione di alimentari e dell’acqua, metodi di conservazione degli alimenti a livello domestico, etc.; i risultati di diverse prove sono stati discussi. / The diet, nutritional status and health are tightly related issues both in industrialized and developing countries. In this doctoral thesis, the main objective was the assessment of nutritional status as a prodromic step to improve it and consenquently health. In industrialized countries, a case study was the nutritional status of a population of central Italy; the intake of some groups of foods, of animal and plant origin, was estimated by food frequency questionnaires and some blood biomarkers. The results demostrated that in dietary controls, aiming to ascertain the long-term effects on health, consumption measurements by questionnaires cannot be exclusive, but some blood and anthropometric indexes could be also useful. In developing countries, two case studies in rural India and D R Congo confirmed that malnutrition is a serious issue; particularly in 3-5 years old children with 26% of severe chronic malnutrition in India and more than 60% in D R Congo. Possible pathways to improve livelihood of rural poor comunities including appropriate food production for a better diet, new income generating activities, infant nutrition improvement, food and waterborn diseases reduction, household food preservation, etc., have been analyzed and the risults of different related trials have been discussed.

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