Detection of TDH-producing Vibrio parahaemolyticus O3: K6 from Naturally Contaminated Shellfish Using an Immunomagnetic Separation Method and Chromogenic Agar Medium

Abstract

We attempted to isolate TDH-producing Vibrio parahaemolyticus O3: K6 from shellfish. Asari samples were incubated with TSB supplemented with 2% (w/v) NaCl for 6h, and then the 6-h cultures were incubated with salt polymyxin broth for 18h. After the two-step enrichment, a 1ml portion of the culture was treated with magnetic beads coated with K6 antibody for immunoconcentration ofV. parahaemolyticus O3: K6. The immunoconcentrated and untreated cultures were plated onto a chromogenic agar and TCBS agar media for isolation of V. parahaemolyticus. TDH-producing V. parahaemolyticus O3: K6 was isolated from 3 out of 66 lots (4.5%) of naturally contaminated Asari. Six of 4, 265 colonies suspected as V. parahaemolyticus (0.14%) were TDH-producing V. parahaemolyticusO3: K6.