Neurotoxin-producing Pseudonitzschia multiseries (Hasle) Hasle, in the Coastal Waters of Southern Korea II. Production of Domoic Acid

Algae > Volume 12(1); 1997 > Article

Algae 1997;12(1): 31-38.

Jin Hwan Lee, Jung Hyun Baik

Department of Biology, Sangmyung University

ABSTRACT

The marine diatom, Pseudonitzschia multiseries was known as a producer of domoic acid. This species was eaten by oysters, clams and blue mussels etc. from which domoic acid was accumulated and extracted. P. multiseries was abundant in the coastal waters of southern Korea, but little has been known concerning toxins in details. In order to determine the presence of domoic acid in the axenic strain of P. multiseries and to certify the occurrence of domoic acid in P. multiseries and mytilus edulis, this study was carried out during the period from April 1993 to May 1995 in Jinhae Bay. A single clone was isolated and cultured by means of f/2 medium and then cultured diatoms were analyzed at each growth stage along with reverse phage HPLC. The aqueous extracts of M. edulis were analyzed with reverse phage HPLC. Domoic acid was also detected in P. multiseries, which has had relations with the food chain between this diatom and M. edulis. Domoic acid of P. multiseries was increased abruptly during the stationary phase (7-15 day), and the domoic acid content per cell was about 1.03 pg/cell. Quantitative analysis of M. edulis yielded variable levels of domoic acid from 30.85-33.55 mg/kg in a cell density of 1.5-9.5 × 10 super(5) cells/l. Toxicity of M. edulis was relatively high during the occurrence of blooms of P. multiseries. Domoic acid-producing P. multiseries was abundant in April and May when the water temperature is 14.8℃ to 19.0℃.

Key words: diatom, domoic acid, neurotoxin, Pseudnitzschia multiseries, southern Korea