The swelling causes theabsorption of fluids from the exterior and thus regulate the release of theentrapped EO from the interior. Erosion mechanism involves dissolutionof the outer part of the wall (surface erosion) or the entire wall (bulkerosion), which often occurs because of the enzyme or chemical hydrolysis. The fragmentation mechanism involves disruption or fractureof the wall matrix, which mainly occurs because of the mechanicalforces.