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Salmonella survival and differential expression of fatty acid biosynthesis‐associated genes in a low‐water‐activity food 全文
2014
Chen, W. | Golden, D.A. | Critzer, F.J.
The purpose of this study was to investigate the difference in expression of fatty acid biosynthesis genes and survival of different serotypes of Salmonella when incubated in a low‐water‐activity (aw) food over a 14‐day period. Stationary cells of five strains of Salmonella enterica belonging to 3 different serovars (Typhimurium ATCC 2486, Enteritidis H4267, Tennessee ARI‐33, Tennessee S13952 and Tennessee K4643) were inoculated into granular sugar (aW = 0·50) and held aerobically over a 14‐day period at 25°C. Survival was determined by enumerating colonies on TSA and XLT‐4 plates at 0, 1, 3, 5, 7 and 14 days. Correspondingly, gene expression was evaluated for three selected genes involved in fatty acid biosynthesis and modification (fabA, fabD and cfa). After 14 days of incubation, the population was reduced from 2·29 to 3·36 log for all five strains. Salmonella Tennessee ARI‐33 and Salm. Tennessee K4643 displayed greater survival than Salm. Typhimurium and Salm. Enteritidis. The increased expression of the cfa gene (involved in cyclopropane fatty acid biosynthesis) over 14 days was found associated with strains with a lower survival rate. The fabA gene (involved in unsaturated fatty acid biosynthesis) was observed up‐regulated for all strains for at least one sampling time and for Salm. Tennessee ARI‐33 for all time points tested, suggesting its potential role in enhancing Salmonella survival in low awfoods. SIGNIFICANCE AND IMPACT OF THE STUDY: Numerous outbreaks of salmonellosis associated with low‐water‐activity foods have been reported. Therefore, the adaptive mechanisms utilized by Salmonella to survive in low‐water‐activity foods for prolonged periods of time need to be better understood. The results in this study showed that low‐water‐activity environments increase expression of gene fabA, which is involved in unsaturated fatty acid biosynthesis of Salmonella, while the increased expression of cfa, associated with cyclopropane fatty acid synthesis, was associated with decreased survival over 14 days.
显示更多 [+] 显示较少 [-]Agrourban sustainability through rooftop greenhouses. Ecoinnovation on residual flows of energy, water and CO2 for food production 全文
2014
Rieradevall Pons, Joan | Llorach Massana, Pere | Sanjuan-Delmás, David | Sanyé Mengual, Esther | Nadal, Ana | Cuerva Contreras, Eva | Planas Rodríguez, Carla | Pons Valladares, Oriol | Josa Garcia-Tornel, Alejandro | Montero Camacho, Juan Ignacio | Muñoz, Pere | Oliver Solà, Jordi | Gabarrell Durany, Xavier | Villalba Mendez, Gara | Rovira, Maria Rosa | Universitat Politècnica de Catalunya. Departament d'Enginyeria de Projectes i de la Construcció | Universitat Politècnica de Catalunya. Departament de Tecnologia de l'Arquitectura | Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental | Universitat Politècnica de Catalunya. GRIC - Grup de Recerca i Innovació de la Construcció | Universitat Politècnica de Catalunya. LiTA - Laboratori d'Innovació i Tecnologia en l'Arquitectura | Universitat Politècnica de Catalunya. MECMAT - Mecànica de Materials
Postprint (published version)
显示更多 [+] 显示较少 [-]The security of water, food, energy and liveability of cities: challenges and opportunities for peri-urban futures
2014
Maheshwari, B. | Purohit, R. | Malano, H. | Singh, V. P. | Amerasinghe, Priyanie
Understanding the impact of crop and food production on the water environment—using sugar as a model 全文
2014
Hess, Tim | Aldaya, Maite | Fawell, John | Franceschini, Helen | Ober, Eric | Schaub, Ruediger | Schulze‐Aurich, Jochen
The availability of fresh water and the quality of aquatic ecosystems are important global concerns, and agriculture plays a major role. Consumers and manufacturers are increasingly sensitive to sustainability issues related to processed food products and drinks. The present study examines the production of sugar from the growing cycle through to processing to the factory gate, and identifies the potential impacts on water scarcity and quality and the ways in which the impact of water use can be minimised. We have reviewed the production phases and processing steps, and how calculations of water use can be complicated, or in some cases how assessments can be relatively straightforward. Finally, we outline several ways that growers and sugar processors are improving the efficiency of water use and reducing environmental impact, and where further advances can be made. This provides a template for the assessment of other crops. © 2013 Society of Chemical Industry
显示更多 [+] 显示较少 [-]Food, water, and energy security in South Asia: A nexus perspective from the Hindu Kush Himalayan region☆ 全文
2014
Rasul, Golam
With limited land resources, inadequate energy supply, and growing water stress, South Asia faces the challenge of providing enough water and energy to grow enough food for the burgeoning population. Using secondary data from diverse sources, this paper explores the food, water, and energy nexus from a regional dimension, emphasizing the role of Hindu Kush Himalayan (HKH) ecosystem services in sustaining food, water, and energy security downstream. The analysis reveals that the issues and challenges in the food, water, and energy sectors are interwoven in many complex ways and cannot be managed effectively without cross-sectoral integration. The most distinctive feature of the nexus in South Asia is the high degree of dependency of downstream communities on upstream ecosystem services for dry-season water for irrigation and hydropower, drinking water, and soil fertility and nutrients. This finding suggests that along with cross-sectoral integration to improve the resource-use efficiency and productivity of the three sectors, regional integration between upstream and downstream areas is critical in food, water, and energy security. Within the nexus approach in South Asia, equal attention should be paid to management of HKH ecosystems–especially the watersheds, catchments, and headwaters of river systems–and to tapping the potential of collaborative gains in water, hydropower, and other ecosystem services through coordination across HKH countries.
显示更多 [+] 显示较少 [-]The security of water, food, energy and liveability of cities: challenges and opportunities for peri-urban futures
2014
Maheshwari, B. | Purohit, R. | Malano, H.M.M. | Singh, Virendra Pal | Amerasinghe, Priyanie H.
Water-based oligochitosan and nanowhisker chitosan as potential food preservatives for shelf-life extension of minced pork 全文
2014
Chantarasataporn, Patomporn | Tepkasikul, Preenapha | Kingcha, Yutthana | Yoksan, Rangrong | Pichyangkura, Rath | Visessanguan, Wonnop | Chirachanchai, Suwabun
Water-based chitosans in the forms of oligochitosan (OligoCS) and nanowhisker chitosan (CSWK) are proposed as a novel food preservative based on a minced pork model study. The high surface area with a positive charge over the neutral pH range (pH 5–8) of OligoCS and CSWK lead to an inhibition against Gram-positive (Staphylococcusaureus, Listeriamonocytogenes, and Bacilluscereus) and Gram-negative microbes (Salmonellaenteritidis and Escherichiacoli O157:H7). In the minced pork model, OligoCS effectively performs a food preservative for shelf-life extension as clarified from the retardation of microbial growth, biogenic amine formation and lipid oxidation during the storage. OligoCS maintains almost all myosin heavy chain protein degradation as observed in the electrophoresis. The present work points out that water-based chitosan with its unique morphology not only significantly inhibits antimicrobial activity but also maintains the meat quality with an extension of shelf-life, and thus has the potential to be used as a food preservative.
显示更多 [+] 显示较少 [-]Review of arsenic contamination, exposure through water and food and low cost mitigation options for rural areas 全文
2014
Sharma, Anitha K. | Tjell, Jens Chr | Sloth, Jens J. | Holm, Peter E.
Arsenic (As) is a toxic metalloid found to be an important groundwater contaminant of mainly natural geogenic origin worldwide particularly in large deltas and along major rivers in poor regions of South- and East-Asia. Excessive and long-term human intake of toxic inorganic As with food and water is causing arsenicosis, which is disfiguring, disabling, and leading to potentially fatal diseases like skin- and internal cancers. It is estimated that more than 100million people mainly in developing countries are at risk. The arsenicosis situation in affected countries has been named the largest chemical threat to public health ever experienced and arsenicosis is spreading to regions where near-sterile well water loaded with As has replaced microbial suspect surface water containing lower As concentrations. This review provides an overview of the state of the art knowledge on the water and food As intake and exposure, and how the As chemistry in water and food may influence chosen mitigation strategies. Although reports on severe health effects from exposure to As in water are abundant there are several weak points in our knowledge on causes and prevalence of arsenicosis in order to devise effective mitigation. The main mitigation strategies focus on drinking water based on exploration of As-free water and As removal from extracted water, whereas mitigation strategies on cooking water and reducing exposure through food are quite often overlooked. The experiences of adopted low cost methods for lowering the human intake of As in rural areas are critically evaluated in terms of public acceptance, sustainability and impact on arsenicosis.
显示更多 [+] 显示较少 [-]DESEMPEÑO DE OVINOS DE LA RAZA SANTA INÊS ALIMENTADOS CON NOPAL Y RESTRICCIÓN DE AGUA 全文
2014
Cordova-Torres Alma | Costa Roberto | Filho José | Alves Neymar
La variabilidad en la precipitación pluvial, torna la alimentación y el agua en factores limitantes para el desempeño animal en las regiones semiaridas. Ante estas dificultades, el objetivo del trabajo fue evaluar la influencia de la inclusión de nopal (Nopalea cohenillifera Salm Dyck) y la restricción de agua sobre el desempeño productivo de ovinos Santa Inês. Fueron utilizados 42 ovinos machos, con edad y peso medio de 100 días y 18.74 kg respectivamente, fueron alimentados con dietas de 0, 30, 50 y 70% de inclusión de nopal hasta alcanzar 32 kg. El diseño experimental fue arreglo factorial 3x2 (inclusión de nopal y niveles de agua: con agua y sin agua). Las variables fueron analizadas usando el test de Tukey a 5%. El agua y su interacción con los tratamientos no tuvo influencia para las variables analizadas. El peso final fue (P< 0.05) mayor para los tratamientos con 30 y 50% de inclusión, con medias de peso 31,78 y 31, 4 kg respectivamente vs 28,43 kg (control). La ganancia total y la ganancia diaria de peso, fueron mayores para los tratamientos con 30 y 50 % , con ganancia total de 13, 27 y 12,23 kg, y 167 y 153g/día respectivamente en comparación con 9,5 kg y 106g/día del tratamiento control. Los días en confinamiento no fueron significativos, siendo 83 dias en promedio. Los niveles de 30 y 50% son los más recomendados, mejoran la ganancia diaria y total de peso, siendo ampliamente recomendada su utilización en los sistemas de producción. | Semiarid conditions are a big challenge for ovine producers | variability in rainfall makes food and water limiting factors for animal performance. Given these difficulties, the spineless cactus has become a permanent ingredient in diets. The objective of this work was to evaluate the influence of spineless cactus inclusion (Nopalea cohenillifera Salm Dyck) and water restriction on the performance of Santa Inês sheep breed. Forty two males were used, with age and average weight of 100 days and 18.74 kg respectively. Animals were fed diets with 0, 30, 50 and 70% inclusion of cactus reaching 32 kg. The experimental design was a 3x2 factorial arrangement (spineless cactus: 30, 50, 70 and water levels: with and without water). Variables were analyzed using the Tukey test to 5% by the PROC GLM procedure of SAS. Water and its interaction with the treatments had no influence on the analyzed variables. The final weight was (P
显示更多 [+] 显示较少 [-]DESEMPEÑO DE OVINOS DE LA RAZA SANTA INÊS ALIMENTADOS CON NOPAL Y RESTRICCIÓN DE AGUA 全文
2014
Cordova-Torres A.V., Costa R.G., Araújo J.T., Alves N.L.