Biodiversity and antifouling activity of fungi associated with two soft corals from the South China Sea

Bacteria in corals have been studied in detail in the past decades. However, the biodiversity and bioactivity of fungi in corals are still poorly understood. This study investigated the biodiversity and antifouling activity of fungi in soft corals Cladiella krempfi and Sarcophyton tortuosum from the South China Sea. A high diverse and abundant fungal community was found in the two soft corals. Furthermore, five isolates shared 83-95% similarity with their closest relatives, indicating that they might be novel species in genera Phaeoshaeria and Mucor. In addition, approximately 50% of the representative isolates exhibited distinct antifouling activity. In particular, isolates Fungal sp. SCAU132 and Fungal sp. SCAU133 displayed very strong antifouling activity against Bugula neritina, suggesting they can provide a potential resource for further investigation on isolation of novel antifouling metabolites. To our knowledge, this study is the first report to investigate the biodiversity and antifouling activity of fungi in C. krempfi and S. tortuosum.