Sylvia DUNCAN is a Microbiologist in the Gut Health Group and her work comprises studies on the impact of dietary macronutrients, including protein and carbohydrate content, on modulating the composition of the gut microbiota and metabolic outputs to improve health and prevent disease. The impact of gut environmental factors, including pH and bile salt levels, on modulating the gut microbiota and metabolism are also being studied. Bacterial cross feeding is being investigated, using in vitro model colonic fermentor systems, as specialist species can utilise lactate, a product that is usually low in healthy colons but can accumulate in disease states. More recently, the formation of secondary metabolites by gut anaerobes are being studied through genome mining strains, testing their ability to inhibit pathogens and thus to identify potentially important compounds that may possess anti-microbial properties.