Production of Vitamins, Exopolysaccharides and Bacteriocins by Probiotic Bacteria

This chapter details the production of three types of complex biomolecules by probiotic bacteria, namely vitamins, exopolysaccharides (EPS) and bacteriocins, and discusses their potential for health promotion in humans. It has been suggested that vitamin production is one of a number of functional characteristics associated with probiotic bacteria and gastrointestinal (GI) microbiota. A large number of lactic acid bacteria (LAB) have been reported to produce vitamins, such as folate (vitamin B 9 ), cobalamin (vitamin B 12 ), menaquinone (vitamin K 2 ), riboflavin (vitamin B 2 ) and thiamine (vitamin B 1 ). A number of LAB, propionibacteria and bifidobacteria can synthesise EPS, which are excreted from the bacterial cells and which may or may not be loosely attached to the cell wall. EPS can contribute to the improved stability, rheology and texture of fermented dairy products, and may also offer protection to bacterial cells against bacteriophage attack, desiccation and osmotic stress.