Filamentous fungi associated with holothurians from the Sea of Japan, off the Primorye coast of Russia

Holothurians (Holothurioidea, Echinodermata) are known to contain triterpen e glycosides, which show antifungal activity. Nevertheless, fungi can be is olated from all organs of holothurians. During 1995-1996, mycelial fungi fr om several Far-Eastern holothurians-Apostichopus japonicus, Eupentacta frau datrix, Cucumaria japonica-were collected from the Sea of Japan near the co ast of Primorye (Russia) and studied. Twenty-seven species of marine fungi, mostly facultative ones belonging to the mitosporic fungi, were isolated f rom the holothurians and identified. Fungi isolated from the holothurian su rface were more diverse and abundant than those from internal organs and co elomic fluids. Of the holothurians studied, Cucumaria japonica was poorest in abundance and diversity of fungi. The fungi Cladosporium brevicompactum and C. sphaerospermum were common in the holothurian coelom. Because of the ir high proteolytic activity, these fungi may be pathogenic to holothurians . The detritovorus holothurian A. japonicus was shown to modify the fungal assemblages within the marine bottom sediments.