Immunochemical methods for detection of probiotics

ANALÍA G. ABRAHAM; MARÍA SERRADELL,; GRACIELA L. GARROTE; ALBERTO C. FOSSATI; GRACIELA L. DE ANTONI

Probiotics in Food Safety and Human Health

CRC Press

Lugar: New York, USA; Año: 2005; p. 165 - 189

Probiotic is a microbial dietary adjuvant that beneficially affects the host physiology by modulating mucosal and systemic immunity, as well as improving nutritional and microbial balance in the intestinal tract. Common criteria used for isolating, characterizing and selecting probiotic microorganisms include the following: strains of human origin, safe for oral administration (GRAS status), stable in the gut environment and specific health related effects. Probiotic action can be ascribed to several mechanisms such as: competitive exclusion, production of antimicrobial substances, modulation of the immune response, alteration of intestinal bacterial metabolic activity, alteration of microecology in human intestine and inhibition of bacterial translocation. Because of their high specificity and sensitivity, immunological methods are useful tools for the identification and detection of microorganisms. Because of the dissimilarity of components of different bacterial species few purification methods are widely applicable and those involves diverse techniques, including chromatography and preparative electrophoresis. Specific antibodies will be used in the future to identify and classify probiotics isolates, to detect and localize probiotic strains in complex communities like intestine, to quantify probiotic strains in food products and feces, to define the mechanism of probiotic action (interaction with epithelium or mucus or other bacteria), to detect extracellular probiotic metabolites (bacteriocins and adhesins), and to study adhesion mechanisms and the role of determined epitopes in surface properties of probiotic microorganisms.. In this section we will discuss only a few  different options that can be particularly helpful in bacteriology, including indirect immunofluorescence, indirect, competitive and capture ELISA, immunoblotting, dot-blot and flow cytometry. Also we will discuss the production of polyclonal and monoclonal antibodies. Development of immunochemical methods for probiotics could be applied to the rational selection and design of novel probiotics as well as to the microbiological control of commercial probiotic products and the detection of probiotics in the gastrointestinal tract.