2.2.2. Fungi

Sea-cucumber-associated fungi belong to 29 genera in 24 families (Table 2). All of them are in the phylum Ascomycota [20–22,27–29,35–45]. The dominant genus was *Aspergillus*, followed by *Penicillium* (Table S1).

Fungi were isolated from six species in five genera of sea cucumbers: *A. japonicus*, *Cucumaria japonica*, *Eupentacta fraudatrix*, *Holothuria nobilis*, *Holothuria poli*, and *Stichopus japonicus* [20,22,29,35–42]. Among them, the greatest number of fungal species was isolated from *H. poli*, with 16 genera. Thirteen genera were isolated from *E. fraudatrix*, and twelve genera were isolated from *A. japonicus*. Two, three, and one genera of fungi were isolated from the sea cucumbers *C. japonica*, *H. nobilis*, and *S. japonicus*, respectively (Table 1 and Table S1).


**Table 1.** Sea cucumbers used for the isolation of culturable microorganisms.


**Table 2.** Culturable microorganisms associated with sea cucumbers.



**Table 2.** *Cont.*

#### **3. Structures and Bioactivities of Natural Products**

To date, 145 natural products have been isolated from sea-cucumber-associated microorganisms (Figure 2). These compounds include polyketides, alkaloids, and terpenoids, among others. These natural products have diverse properties, such as cytotoxic [37,39,45], antimicrobial [44], enzyme-inhibiting [46], and antiangiogenic activities [47].
