Quellung reaction is seen in
High-Yield Explanation
Quellung reaction is seen in Streptococcus pneumoniae Quellung reaction: a specific test of Streptococcus pneumoniae. A suspension of Streptococcus pneumoniae is mixed with a drop of type-specific antiserum and a loopful of methylene blue solution. In the presence of homologous antiserum, the capsule becomes apparently swollen, sharply delineated and refractile. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 225