*2.5. Aspergillus sp. from Corals and Their Antimicrobial Activities*

Three known metabolites, including demethylincisterol A2 (**29**), asperophiobolin E (**30**) and butyrolactone I (**31**), were isolated and identified from the soft coral fungus *A. hiratsukae* SCSIO 5Bn1003 (Figure 5). Compounds **29**–**31** showed potent antibacterial activity against *B. subtilis*, with MIC values of 10.26 ± 0.76, 17.00 ± 1.25 and 5.30 ± 0.29 μM. Meanwhile, asperophiobolin E and butyrolactone I showed weak activity against *S. aureus*, with MIC values of 102.86 ± 4.50 and 59.54 ± 0.50 μM, respectively [61].

Five new antimicrobial α-pyranone methterpenoids H-L (**32**–**36**) and one known antimicrobial compound, namely neoechinulin A (**37**), were isolated from *A. hiratsukae* SCSIO 7S2001, a fungus derived from ophiophora coral. Methterpenoids H-L and neoechinulin A showed varying degrees of antibacterial activity, with MIC values of 6.25–100 μg/mL. The MIC values of methterpenoid H were 6.25 μg/mL for *Micrococcus lutea* 01, MRSA, and *Streptococcus faecalis*; that of methterpenoid I was 6.25 μg/mL for MRSA; that of methterpenoid G was 12.5 μg/mL for MRSA; that of methterpenoid K was 6.25 μg/mL for *Klebsiella pneumoniae*; that of methterpenoid L was 12.5 μg/mL for *M. lutea*, *S. faecalis* and MRSA; and that of neoechinulin A was 12.5 μg/mL for *S. faecalis*. [62].

Two butenolides, including versicolactone B (**38**) and butyrolactone VI (**39**), were isolated from *Aspergillus terreus* SCSIO41404, a fungus derived from coral. Versicolactone B and butyrolactone VI showed weak antibacterial activity against *Enterococcus faecalis* and *K. pneumoniae* with IC50 values of 25 and 50 μg/mL, respectively [63].

Six chlorinated polyketones were isolated from the coral fungus *A. unguis* GXIMD 02505 in the Beibu Gulf. These polyketones included aspergillusethers J and F (**40** and **41**), nornidulin (**42**), aspergillusidones B and C (**43** and **44**) and 1-(2, 6-dihydroxy-4-methoxy-3, 5-dimethylphenyl)- 2-methylbutan-1-one (**45**). Compounds **40**–**45** exhibited inhibitory activities against marine biofilm-forming bacteria, *Marinobacterium jannaschii*, MRSA, *Microbulbifer variabilis* and *Vibrio pelagius*, with MIC values ranging from 2 to 64 μg/mL [64].

Five antimicrobial cyclic lipopeptides, namely maribasins C-E (**46**–**48**) and maribasins A and B (**49** and **50**), were isolated from the marine fungus *Aspergillus* sp. SCSIO 41501. These compounds showed strong antifungal activities against five plant pathogenic fungi, with MIC values ranging from 3.12 to 50 μg/disc [34].

In conclusion, coral-derived *Aspergillus* and its active metabolites were summarized. Twenty-two antimicrobial compounds were found in five fungi strains of coral origin. It was a relatively large variety of compounds compared with *Aspergillus* from other origins. Most of the compounds had a wide antimicrobial spectrum against different bacteria and fungi.

**Figure 5.** Compounds of *Aspergillus* sp. derived from corals.
