obtained from the green alga Codium fragile collected from the coast of Dalian.
Aspeverin (492) inhibited growth of the marine phytoplankton Heterosigma
akashiwo with EC 50 values of 6.3 and 3.4 μg/cm
3 after 24 and 96 h, respectively
[152]. When grown on solid 2216E medium, Aspergillus sp. Z-4, a gut-derived
fungus from the marine isopod Ligia oceanica collected in Zhoushan, Zhejiang
Province, gave asperginine (493) [153]. The fermentation in liquid PDB medium of
Paecilomyces variotii EN-291, an endophyte obtained from the red alga Grateloupia
turuturu, yielded two indole alkaloids varioloids A and B (494 and 495). Both
compounds exhibited cytotoxicity against the A549, HCT116, and HepG2 cell
lines with IC 50 values ranging from 2.6 to 8.2 μg/cm
3 [154]. Communol B (496)
was isolated from a liquid GPY medium cultivation of Penicillium commune 518, a
fungus associated with the gorgonian Muricella abnormalis collected in Danzhou,
Hainan Province (Fig. 28) [28].
7.2 Quinolone and Quinazoline Derivatives
The fungal strain Aspergillus sp. XS-20090B15 was derived from the gorgonian
Muricella abnormalis collected in the South China Sea. Solid rice fermentation of
this fungus led to the isolation of two prenylated dihydroquinolone derivatives,
22-O-(N-methyl-L-valyl)aflaquinolone B and 22-O-(N-methyl-L-valyl)-21-epiaflaquinolone B (497 and 498) (Fig. 29). Compound 498 showed significant antiviral
activity against the human respiratory syncytial virus (RSV) with an IC 50 value of
42 nM, approximately 500-fold more potent than that of the positive control ribavirin
(IC 50 20 μM). The compound furthermore showed a high therapeutic ratio (TC 50 /
IC 50 ¼ 520), whereas its 21-epimer 497 exhibited no antiviral activity, suggesting
that the configuration of the cyclohexane unit plays a key role in the anti-RSV
activity [155].
3-Methoxyviridicatol (499), a 2-quinolinone derivative, was obtained from liquid
potato sucrose medium fermentation of Penicillium crustosum AP2T1, a fungus
derived from the fresh gill tissue of the shark Isurus oxyrinchus that was captured by
fishermen in the Wenzhou marine area of Zhejiang Province [156]. When grown in
liquid medium composed of sorbitol, yeast extract, maltose, and NaCl, the
gorgonian-derived fungus Aspergillus terreus SCSGAF0162, which was obtained
from Echinogorgia aurantiaca collected from Sanya, Hainan Province, yielded
terremide C (500) [141]. A cyclopenin derivative, 9-hydroxy-3-methoxyviridicatin
(501), and four quinazoline derivatives, versicomides AÀD (502–505), were
obtained from the liquid potato dextrose fermentation of Aspergillus versicolor
XZ-4, derived from the crab Xenograpsus testudinatus collected from Kueishantao,
Taiwan. 9-Hydroxy-3-methoxyviridicatin (501) exhibited inhibitory activities
against Escherichia coli with a MIC value of 32 μg/cm
3 [157]. Another fungal strain
of Aspergillus versicolor coded LZD-14-1 was obtained from the gorgonian
Pseudopterogorgia sp. collected from the South China Sea. Fermentation of this
fungus on solid rice medium resulted in the isolation of eleven fumiquinazoline-type
Secondary Metabolites from Marine-Derived Fungi from China
127
Aspeverin (492) inhibited growth of the marine phytoplankton Heterosigma
akashiwo with EC 50 values of 6.3 and 3.4 μg/cm
3 after 24 and 96 h, respectively
[152]. When grown on solid 2216E medium, Aspergillus sp. Z-4, a gut-derived
fungus from the marine isopod Ligia oceanica collected in Zhoushan, Zhejiang
Province, gave asperginine (493) [153]. The fermentation in liquid PDB medium of
Paecilomyces variotii EN-291, an endophyte obtained from the red alga Grateloupia
turuturu, yielded two indole alkaloids varioloids A and B (494 and 495). Both
compounds exhibited cytotoxicity against the A549, HCT116, and HepG2 cell
lines with IC 50 values ranging from 2.6 to 8.2 μg/cm
3 [154]. Communol B (496)
was isolated from a liquid GPY medium cultivation of Penicillium commune 518, a
fungus associated with the gorgonian Muricella abnormalis collected in Danzhou,
Hainan Province (Fig. 28) [28].
7.2 Quinolone and Quinazoline Derivatives
The fungal strain Aspergillus sp. XS-20090B15 was derived from the gorgonian
Muricella abnormalis collected in the South China Sea. Solid rice fermentation of
this fungus led to the isolation of two prenylated dihydroquinolone derivatives,
22-O-(N-methyl-L-valyl)aflaquinolone B and 22-O-(N-methyl-L-valyl)-21-epiaflaquinolone B (497 and 498) (Fig. 29). Compound 498 showed significant antiviral
activity against the human respiratory syncytial virus (RSV) with an IC 50 value of
42 nM, approximately 500-fold more potent than that of the positive control ribavirin
(IC 50 20 μM). The compound furthermore showed a high therapeutic ratio (TC 50 /
IC 50 ¼ 520), whereas its 21-epimer 497 exhibited no antiviral activity, suggesting
that the configuration of the cyclohexane unit plays a key role in the anti-RSV
activity [155].
3-Methoxyviridicatol (499), a 2-quinolinone derivative, was obtained from liquid
potato sucrose medium fermentation of Penicillium crustosum AP2T1, a fungus
derived from the fresh gill tissue of the shark Isurus oxyrinchus that was captured by
fishermen in the Wenzhou marine area of Zhejiang Province [156]. When grown in
liquid medium composed of sorbitol, yeast extract, maltose, and NaCl, the
gorgonian-derived fungus Aspergillus terreus SCSGAF0162, which was obtained
from Echinogorgia aurantiaca collected from Sanya, Hainan Province, yielded
terremide C (500) [141]. A cyclopenin derivative, 9-hydroxy-3-methoxyviridicatin
(501), and four quinazoline derivatives, versicomides AÀD (502–505), were
obtained from the liquid potato dextrose fermentation of Aspergillus versicolor
XZ-4, derived from the crab Xenograpsus testudinatus collected from Kueishantao,
Taiwan. 9-Hydroxy-3-methoxyviridicatin (501) exhibited inhibitory activities
against Escherichia coli with a MIC value of 32 μg/cm
3 [157]. Another fungal strain
of Aspergillus versicolor coded LZD-14-1 was obtained from the gorgonian
Pseudopterogorgia sp. collected from the South China Sea. Fermentation of this
fungus on solid rice medium resulted in the isolation of eleven fumiquinazoline-type
Secondary Metabolites from Marine-Derived Fungi from China
127