Agency: GTR | Branch: BBSRC | Program: | Phase: Intramural | Award Amount: 104.92K | Year: 2015
The substantial economic and health impact of pathogens of the genus Salmonella is the result of their entry into and survival within the food chain, and their ability to cause disease. Salmonella are a diverse group of pathogens in which some variants are more likely to be associated with disease in humans than others. One of the factors governing this is the adaptation to host species that are important sources of food. Recently an epidemic spanning three years was associated with S. Typhimurium (STM) DT8 that was specifically associated with duck eggs. Recent research from my lab revealed that DT8 is part of a cluster of genotypes adapted to circulation in populations of poultry, ducks and geese. But what are the genomic or transcriptomic features specific to these clusters that result in their association with the avian host and transmission through the food chain? Polymorphisms associated with essential genes, or altered transcriptional response of essential genes, that are specific to strains belonging to genotypic clusters associated with altered risk to food safety are candidate molecular markers of risk to food safety. The overall aim of this project is to determine the essential genes and transcriptional response of STM DT8 compared with non-DT8 variants. The central hypothesis is that a distinct transcriptional response and sets of genes are associated with S. Typhimurium DT8 in environments encountered in the host and during transmission. The significance of the project is that it will inform strategies to intervene in transmission of food borne pathogens through the food chain and identify pathogens in their zoonotic reservoirs.
Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 113.56K | Year: 2015
Palm Paper Ltd. recycles 400K tonnes of waste newsprint annually. This creates 140,000 tonnes paper crumble (PC) waste which costs £4m to dispose of by landspreading. PC comprises approximately 15-20% cellulose and 70% paper filler (calcium carbonate) with a little latex. The aim of this research is to evaluate the feasibility of innovatively digesting the cellulose to liberate glucose and to then refine the large carbonate fraction for re-incorporation into the newspaper production process. This will avoid disposal and reduce the import of new paper filler. The research will also assess the feasibility of converting the liberated glucose to chemicals and fuel ethanol by fermentation with specialist yeasts identified from the UK National Collection of Yeast Cultures at Norwich. The study will build on preliminary research carried out at the Biorefinery Centre, IFR, Norwich, in conjunction with industrial research expertise of Palm Paper, Lenzing, plc and Vireol plc. Additional sources of cellulose waste (e.g. waste paper, cellulose fibres) will be incorporated into the study to improve economies of scale as required. In this way, the project will serve to address three IB challenges: production of commodity, platform and intermediate chemicals and materials; production of liquid and gaseous biofuels and novel or improved upstream or downstream processes to reduce costs and improve efficiency.
Agency: GTR | Branch: BBSRC | Program: | Phase: Intramural | Award Amount: 178.79K | Year: 2015
Sirtuin 1 (SIRT1) is a NAD+ histone III deacetylase that links the energy status of the cell with the regulation of metabolism, cell protection, inflammation and other vital processes that preserve whole-body homeostasis. SIRT1 mediates a healthy aging and protects the liver against dietary-induced metabolic disease, whereas we recently described the pro-tumorigenic characteristic of this deacetylase in the liver. Our most recent findings showing the detrimental implication of SIRT1 in (murine and human) cholestatic disease support the complexity of SIRT1 signaling and highlight the importance of defining specificity of SIRT1 function in different cellular contexts. Importantly, increasing evidences point to the relevance of the communication between the liver and the gut in preserving liver homeostasis and how disturbances in gut function may influence the progression of chronic liver diseases such as metabolic syndrome and cholestasis. Taking all these together, our research aims to understand the role of SIRT1 in regulating the liver-gut interaction to preserve life-long health and how SIRT1 may influence the progression of chronic liver disease. To understand the implication of SIRT1 in these processes will allow us to propose new therapeutic strategies based on the modulation of this deacetylase to preserve health. Our multidisciplinary work involves the use of diverse techniques including molecular biology, immunology and high throughput technologies (transcriptomics, proteomics and metabolomics) for the in depth analysis of samples obtained from in vitro, in vivo (from transgenic animals conventionally raised or in germ-free conditions) and ultimately in human specimens. We anticipate that our results will enable us to develop interventional opportunities aiming to maintain and/or restore gut and liver homeostasis and to preserve a life-long health.
Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 415.77K | Year: 2015
The bacterium Salmonella accounts for about 125 million incidents of disease worldwide each year, and nearly a million deaths. The morbidity and mortality caused by this pathogen has a significant impact on the economies of both resource rich and resource poor countries. Most cases of non-typhoidal Salmonella are thought to result from fecal contamination of food and food products, either directly in the food chain or by cross contamination in the home or restaurants. A common and therefore critical step for this is the entry of the bacterium into the food chain from livestock and poultry in which this pathogen is commonly found. However, even though virtually all types of Salmonella have the potential to cause disease in man, not all are commonly associated with disease in man. Understanding how these processes work is critical to the detection of high risk types of Salmonella in livestock and the food chain, and efforts to decrease the likelihood of Salmonella entering these environments. We propose to study two common types of Salmonella that are both present in pig herds butter present distinct risk to food safety. We will study these bacteria at a genetic and behavioural level to understand how the different types circulate in pig populations in the UK and how they enter and survive in our food. First a collection of pig and food chain isolates of Salmonella Typhimurium will be whole genome sequenced and the variation in their genome used to define the how they spread into the food chain and into the human population. Then we will study important behavioural variations that may impact the threat posed by the variants in food. As the types of Salmonella to be studied are genetically closely related, the number of genetic differences are small, which makes it possible to identify candidate differences associated with altered behaviours of the variants. Genetic differences in types of Salmonella are potential candidates targets for surveillance to identify types more likely to represent a risk to food safety or for other intervention strategies aimed at decreasing the likelihood that they will enter the food chain.
Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 143.31K | Year: 2016
This project will deliver rapidly a formulation engineering route to salt or sugar reduction in sauces, dressings, soups and milk shakes. It will also provide non-chemically modified starches as food emulsifiers. The novelty lies in programming one of the formulation ingredients, starch, for dual purpose: product stabilisation and taste experience using ingredients acceptable to consumers. There are a range of novel strategies to reduce salt and sugar content in dry/solid foods, but these are not practical in liquid foods due to the high solubility of salt and sugar in water. Therefore this project specifically targets the salt or sugar levels of liquid and semi-liquid foods where salt or sugar is primarily added for taste rather than preservation, a particular challenge for the food industry. We hypothesise that the formulation levels of these undesirable nutrients can be reduced without taste compromise by encapsulation in a fashion that, while the delivery vehicles remain stable during shelf life, they break down in the mouth, close to the taste receptors to deliver the tastant right where it will be perceived. Currently salt or sugar is delivered to the taste receptors through the bulk of the food and taste intensity correlates to concentration. Delivery of pockets of sufficiently high concentrations of salt or sugar near the taste receptors will enable lowering their overall concentration in the bulk of the food that is swallowed without contributing to taste. The proposed approach is to use water-in-oil-in-water emulsions (wow/s) to encapsulate the salt or sugar, which will be protected by a starch based shell. This starch will be designed to break down when brought into contact with saliva, thus releasing high concentrations of salt or sugar close to taste receptors in the mouth. wow emulsions are oil-in-water (o/w) emulsions where the oil droplets are filled with water droplets. Although wow/s have been talked about for some time, they can be very difficult to stabilise to give a long shelf life and therefore are not found in commercial foods or drinks. What happens is termed emptying out: the internalised water diffuses through the oil into the external water phase slowly converting the wow into a simple o/w. There have been different approaches to reduce emptying out, but perhaps the only practically relevant method for this project is through particle stabilisation of the external o/w interface. This has recently been demonstrated to be possible with OSA starch (a chemically modified starch) that is well known to be a good emulsifier. Native starches with small granules have also been reported to show emulsifying ability although our own attempts have shown limited stability. It can be predicted that native starches will not be widely functional across the broad spectrum of emulsion based foods and drinks. Chemical modification of food ingredients is not desired by consumers, so we will explore physical modification via extrusion processing and milling to program starches as emulsifier & for break down delivery of salt or sugar near the taste receptors during consumption. As salivary amylase will be the tastant release trigger, individuals or consumer groups amylase levels will be considered in developing this pathway for salt or sugar reduction. We have proof-of-concept sensory data indicative of the potential success of the proposed technology based on formulating with a commercial OSA starch. Emulsion stability was excellent although encapsulation efficiency was not optimised for product storage. The internal water phase was stabilised with polyglycerol polyricinoleate (PGPR) as in most researches despite the limitations for use of PGPR in processed foods. In this research alternative approaches to stabilise the internal water phase, e.g., by a fat crystal network (which is known to be successful), extremely hydrophobic starches or other food particles not requiring chemical modification will be applied.