Two fucoidans in the holdfast of cultivated Laminaria japonica.

Two fucoidans have been isolated from the holdfast of cultivated Laminaira japonica. One (L-fucoidan) is rich in fucose and sulfate; the other (GA-fucoidan) is rich in uronate. L-fucoidan was found in the fronds of L. japonica (cultivated and wild), L. angustata, and Kjellmaniella crassifolia whereas GA-fucoidan was not detected in these fronds and may be a fucoidan specific to the holdfast. These two fucoidans were proved to have anti-tumor activity against Adenocarcinoma 755-transplanted mice by i.p. and p.o. administration.