GUT FLORA IN NORMAL AND DISORDERED STATES

Infections of the gastrointestinal tract are a major health problem fo r both adults and children worldwide. Changes in the normal human gut microflora result in the development of intestinal disorders. Pathogen ic bacteria alter the intestinal microecology and intestinal colonizat ion resistance. A healthy gastrointestinal microflora forms a barrier against invading organisms. Normal intestinal microbes and some probio tic bacteria can enhance the host's defence mechanisms against pathoge ns. They can also improve intestinal immunity by adhering to intestina l mucosa and stimulating local immune responses. Thus the maintenance of a balanced intestinal microecology improves the ability to preserve intestinal integrity.