The invention provides an isolated, anti-inflammatory, cytoprotective compound that is soluble in aqueous fluid, is derivable from the conditioned medium of a probiotic culture, such as VSL#3, induces heat shock protein expression, and has shown the capacity to inhibit NF-.kappa.B activation. The compound is amenable to formulation in a pharmaceutical composition and to packaging in a kit form with instructions for use in methods according to the invention, which include methods of preventing, treating, or ameliorating a symptom of an inflammatory disorder, such as an inflammatory epithelial disease, e.g., inflammatory bowel disease, characterized by inflammation.