Capsules in Biology and Pharmaceutics

Biological Capsule

A layer of polysaccharides surrounding the cell wall of some bacteria, composed of complex carbohydrates (glucose, galactose, mannose). Functions include protection from environmental stresses (desiccation, temperature extremes, chemicals), adhesion, nutrient acquisition, host tissue colonization, and immune evasion.

Pharmaceutical Capsule

A solid dosage form: a small cylindrical container (gelatin or other material) containing powdered or liquid drug(s). Taken orally; gelatin dissolves in stomach, releasing drug for absorption. Used for drugs with unpleasant taste/odor or acid sensitivity.