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Unifying Prolonged Copper Exposure, Accumulation, and Toxicity from Food and Water in a Marine Fish Полный текст
2012
Dang, Fei | Wang, Wen-Xiong | Rainbow, P. S.
The link between metal exposure and toxicity is complicated by numerous factors such as exposure route. Here, we exposed a marine fish (juvenile blackhead seabream Acanthopagrus schlegelii schlegelii) to copper either in a commercial fish diet or in seawater. Copper concentrations in intestine/liver were correlated linearly with influx rate, but appeared to be less influenced by uptake pathway (waterborne or dietary exposure). Influx rate best predicted Cu accumulation in the intestine and liver. However, despite being a good predictor of mortality within each pathway, influx rate was not a good predictor of mortality across both exposure pathways, as waterborne Cu caused considerably higher mortality than dietary Cu at a given influx rate. We show that the use of gill Cu accumulation irrespective of the exposure route as a model for observed fish mortality provided a clear relationship between accumulation and toxicity. Investigation of gill Cu accumulation may shed light on the different accumulation strategies from the two exposure pathways. This correlation offers potential for the use of branchial Cu concentration as an indicator of long-term Cu toxicity, allowing for differences in the relative importance of the uptake pathways in different field situations.
Показать больше [+] Меньше [-]Escherichia coli isolated from food sources and irrigation water: A potential risk for causing intestinal dysfunction? Полный текст
2019
Aijuka, Matthew | Santiago, Araceli E. | Girón, Jorge A. | Nataro, James P. | Buys, Elna M.
We have previously shown that diarrheagenic Escherichia coli (DEC) and non-DEC are prevalent in food sources and irrigation water in South Africa. Recent data suggest that an increased relative abundance of faecal Enterobacteriaceae is associated with poorer health outcomes among children in developing countries. Thus, exposure to non-DEC from environmental sources may incur adverse effects, although the mechanisms underlying these effects remain obscure. To further elucidate this phenomenon, we assayed non-DEC strains from environmental sources in South Africa for phenotypes that may be associated with intestinal dysfunction (ID). DEC strains were also used. The strains had previously been isolated from Producer Distributor Bulk Milk (PDBM), irrigated lettuce, street vendor coleslaw and irrigation water.In-vitro assays identified; biofilm formation (n = 38), extracellular polymeric substance (EPS) formation (n = 38), cytotoxic activity (n = 10), disruption of tight junctions and induction of Interleukin 8 (IL-8) on polarized T-84 cells (n = 20). The number of strains tested for each assay differed, depending on prior molecular and phenotypic characterization that signalled potential pathogenicity in-vitro. Subsequently, all strains having data points for all analyses were used to compute Principal Component Analysis (PCA) plot curves to infer potential associations amongst test strains and a standard DEC pathogenic strain (042).Biofilm formation on glass coverslips after strains were grown in nutrient-rich media (LB and DMEM-F12 + 0.5% D-Mannose) at 37 °C varied based on pathotype (DEC and non-DEC) and source of isolation (food, irrigation water, clinical) suggesting that pathotype and source isolation influence persistence within a defined environmental niche. Additionally, DEC isolated from irrigated lettuce had a significantly higher (p ≤ 0.05) propensity for biofilm formation in both media compared to all strains including DEC standard controls. This suggested the propensity for irrigated lettuce as a potential source of persistent pathogenic strains. Furthermore, all strains were able to form EPS suggesting the ability to form mature biofilms under conditions relevant for food processing (20–25 °C). Of the (60%, 6 out of 10) strains that showed cytotoxic activity, most (83%, 5 out of 6 strains) were non-DEC isolated from food sources many of which are consumed with minimal processing.Mean percentage reduction in initial TEER (a measure of intestinal disruption), did not significantly differ (p = 0.05) in all test strains from that observed in the standard DEC. Additionally, IL-8 induction from strains isolated from PDBM (139 pg/mL), irrigation water (231.93 pg/mL) and irrigated lettuce (152.98 pg/mL) was significantly higher (p ≤ 0.05) than in the commensal strain aafa. PCA categorized strains based on sources of isolation showed potential for use in source tracking especially when comparing many strains from various environmental sources. We show that non-DEC strains along the food chain possess characteristics that may lead to ID. Further investigations using a larger collection of strains may provide a clearer link to these reported observations that could be associated with the high diarrheal disease burden within the country, especially among infants.
Показать больше [+] Меньше [-]Physicochemical and in vitro biological validation of food grade secondary oil in water nanoemulsions with enhanced mucus-adhesion properties Полный текст
2022
Lagreca, Elena | Vecchione, Raffaele | Di Cicco, Chiara | D’Aria, Federica | La Rocca, Alessia | De Gregorio, Vincenza | Izzo, Luana | Crispino, Raffaele | Mollo, Valentina | Bedini, Emiliano | Imparato, Giorgia | Ritieni, Alberto | Giancola, Concetta | Netti, Paolo Antonio
Among oral delivery systems, oil in water nano-emulsions (O/W NEs) are of particular interest to improve pharmacokinetics of lipophilic compounds. Recently, we have implemented a successful strategy to improve O/W NEs stability, based on a polymeric coating on an oil core, namely secondary O/W NEs, through the use of pharma grade formulations. However, in the field of food supplements, food grade materials are the top choice since they combine safety and cost effectiveness. Here, we have replaced pharma grade (PG) with food grade (FG) materials in the preparation of the polymer coated O/W NEs, and performed a comparative study between the two formulations to assess the FG one. At the same time, in order to provide formulations with enhanced mucus-adhesion to the intestinal barrier, secondary O/W NEs were prepared by adding thiol groups to chitosan (Ct) via a simple non-covalent procedure based on N-acetyl-cysteine (NAC) salification, thus easily implementable to a food supplement formulation. PG and FG formulations, in different materials combinations, were prepared and physico-chemically characterized (DLS, ¹H NMR, ITC, CRYO-TEM) showing similar behaviour. FG formulations (NEs, Ct-NEs and Ct-NAC-NEs) loaded with curcumin were prepared and compared with the free drug in terms of drug bioaccessibility through the INFOGEST protocol confirming improved bioaccessibility. Very interestingly, by comparing mucus-adhesion properties of the two polymeric coatings (Ct and Ct-NAC) within an intestine on chip device able to mimic the complex intestinal functions, a significant enhancement in the mucus-adhesive properties of the proposed novel Ct-NAC-NE formulation was observed with respect to Ct due to the presence of thiol groups. Nonetheless, in-vivo assays are required as a final assessment of the proposed system.
Показать больше [+] Меньше [-]Effect of milk proteins and food-grade surfactants on oxidation of linseed oil-in-water emulsions during in vitro digestion Полный текст
2019
Lamothe, Sophie | Desroches, Vincent | Britten, Michel
Health benefits are associated with polyunsaturated fatty acids, but their sensitivity to oxidation may generate toxic oxidation species. The objective of this study was to compare the effect of milk proteins (casein, whey protein) and surfactants (Citrem, Tween 20) on the in vitro digestion and oxidation of linseed oil emulsions. The emulsion produced with Tween 20 resisted coalescence in the gastric phase and showed the highest concentrations of free fatty acids and reactive carbonyl compounds in the intestinal digestion phase. The Citrem-stabilized emulsion showed extensive coalescence in the gastric environment, which reduced lipolysis and the formation of advanced oxidation species. The protein-stabilized emulsions showed aggregation with some coalescence in the gastric phase, and casein provided better protection than whey protein against oxidation. This study suggests that the mechanism of emulsion destabilization in the gastric environment and the type of protein can modulate lipolysis and oxidation during in vitro digestion.
Показать больше [+] Меньше [-]Food-borne and water-borne diseases under climate change in low- and middle-income countries: Further efforts needed for reducing environmental health exposure risks Полный текст
2019
Cissé, Guéladio
This paper provides a view of the major facts and figures related to infectious diseases with a focus on food-borne and water-borne diseases and their link with environmental factors and climate change. The global burden of food-borne diseases for 31 selected hazards was estimated by the World Health Organization at 33 million disability-adjusted life years (DALYs) in 2010 with 40% of this burden concentrated among children under 5 years of age. The highest burden per population of food-borne diseases is found in Africa, followed by Southeast Asia and the Eastern Mediterranean sub-regions. Unsafe water used for the cleaning and processing of food is a key risk factors contributing to food-borne diseases. The role of quality and quantity of water to the general burden of infectious diseases deserves attention, particularly in low- and middle-income countries, as its effects go beyond the food chain. Water-related infectious diseases are a major cause of mortality and morbidity worldwide, and climate change effects will exacerbate the challenges for the public health sector for both food-borne and water-borne diseases. Selected case studies from Africa and Asia show that (i) climate change extreme events, such as floods, may exacerbate the risks for infectious diseases spreading through water systems, and (ii) improvements related to drinking water, sanitation and hygiene could result in a significant reduction of intestinal parasitic infections among school-aged children. There is a need to better anticipate the impacts of climate change on infectious diseases and fostering multi-stakeholder engagement and multi-sectoral collaborations for integrated interventions at schools, community and household levels. The paper calls for giving priority to improving the environmental conditions affecting food-borne and water-borne infectious diseases under climate change.
Показать больше [+] Меньше [-]Evaluation of dairy food processing wash water solids as a protein source. II. Microbial protein synthesis, duodenal nitrogen flow, and small intestinal amino acid disappearance
1991
Caton, J.S. | Williams, J.E. | May, T. | Belyea, R.L. | Beaver, E.E. | Tumbleson, M.E.
Twelve ruminally, duodenally, and ileally-cannulated Hereford heifers (average initial BW 313 +/- 20 kg) were used in a replicated experiment to evaluate dairy food processing wash water solids (WWS) as a protein source. Heifers were fed 2.8 kg of chopped (7.6 cm) hay and one of three supplements (1.5 kg/d, DM basis). Supplements were formulated to be similar in energy and contained 1.0 (control), 23.2 (WWS), and 21.6% (soybean meal; SBM) CP on an OM basis. Total N and nonammonia N entering the duodenum (g/d) were greater (P <. 10) for heifers fed WWS and SBM supplements than for controls. Bacterial N flow (g/d) at the duodenum was less (P < .10) for controls (43.9) than for WWS- (63.9) and SBM- (69.9) supplemented heifers. Feed escape N (g/d) was greater (P < .10) for WWS-fed heifers than for those fed SBM (32.1 vs 20.7 g/d, respectively). Total tract N digestion (g/d) was greatest (P < .10) for SBM, intermediate for WWS, and least for control heifers. Microbial protein synthesis (g/kg of OM intake) was enhanced (P < .10) by WWS and SBM supplementation, but efficiency of synthesis (g/kg of OM fermented) did not differ among treatments. Essential amino acid (AA) disappearance in the small intestine (g/d) was less (P < .10) for control than for the other two treatments. Nonessential AA disappearance was greatest (P < .10) for the WWS and least (P < .10) for the control treatment. Based on our short-term feeding data, WWS can be used as a protein source for ruminants, but N availability of WWS seems less than that of soybean meal.
Показать больше [+] Меньше [-]Microflora in the alimentary tract of Tilapia, 2: Comparison among micro-flora of intestine, sediment and pond water
1982
Sakata, T. | Higashi, H. | Kakimoto, D. (Kagoshima Univ. (Japan). Faculty of Fisheries)