F (455 and 456). Versicotides DÀF (454–456) showed cholesterol-lowering effects
at a dose of 10 μM, comparable to simvastatin through the regulation of cholesterol
efflux to HDL in RAW264.7 macrophages. The mechanism of action was explained
through promotion of the target genes ABCG1 and LXRa and a decrease in critical
scavenger receptors CD36 and SR-1/SR-2 [139]. A further fungal strain of Aspergillus versicolor was isolated from the gorgonian Carijoa sp. collected from the
Weizhou coral reefs in the South China Sea. Solid rice medium fermentation of this
fungus gave a cyclic hexapeptide, aspersymmetide A (457) [140]. The fungal strain
Aspergillus terreus was isolated from the gorgonian Echinogorgia aurantiaca
collected from Sanya, Hainan Province. An unusual cyclic tetrapeptide,
asperterrestide A (458), containing anthranilic acid and 3-OH-N-Me-Phe moieties,
was obtained from fermentation of this fungus in liquid medium composed of
maltose, NaCl, sorbitol, and yeast extract. Asperterrestide A (458) exhibited cytotoxic activity against the U937 and MOLT4 human carcinoma cell lines with IC 50
values of 6.4 and 6.2 μM, respectively, and also displayed antiviral activity against
the H1N1 and H3N2 influenza viral strains, having IC 50 values of 15.0 and 8.1 μM
(Fig. 25) [141].
A strain of Aspergillus versicolor was isolated from the soft coral Cladiella
sp. collected from Lingao, Hainan Province. Three cyclopentapeptides,
versicoloritides AÀC (459–461) (Fig. 26), were obtained following fermentation
of this fungus in liquid medium composed of sea salt, sorbitol, maltose, and yeast
extract [66]. The fungus Aspergillus clavatus was isolated from the shell of the crab
Xenograpsus testudinatus collected from hydrothermal vents in Kueishantao near
Taiwan. From the mycelium and broth obtained from a cultivation of the fungus in
liquid potato medium, two anthranilic acid-containing cyclic depsipeptides,
clavatusides A and B (462 and 463), were isolated, while cultivation in a zincenriched medium yielded the cyclic pentapeptide clavatuside C (464). Clavatusides
A and B (462 and 463) suppressed the proliferation of the HepG2, SMMC-7721, and
Bel-7402 hepatocellular carcinoma cell lines in a dose- and time-dependent manner
with IC 50 values ranging between 32 and 64 μM. Clavatuside B (463) was also active
against several other human cancer cell lines including pancreatic cancer (Panc-1),
gastric cancer (MGC-803), colorectal cancer (SW-480), retinoblastoma (WERI-Rb1), and prostate cancer (PC3) cell lines in a dose-dependent manner with IC 50 values
ranging between 32 and 42 μM [142, 143].
A cyclic tetrapeptide (465), containing the unusual amino acids 3-aminoacrylic
acid and 3-methoxyanthranilic acid, was isolated from the solid rice medium fermentation of Aspergillus flavipes obtained from the gut of the marine isopod Ligia
oceanica collected in Zhoushan, Zhejiang Province [144]. A strain of Nigrospora
oryzae was obtained from the inner tissue of the sponge Phakellia fusca collected
from Yongxing Island in the South China Sea. Fermentation of this fungus in liquid
PDA medium yielded three cyclohexadepsipeptides, oryzamides AÀC (466–468),
and two isolation artifacts, oryzamides D and E (469 and 470), which are methionine
sulfoxide diastereomers. Oryzamides AÀE (466–470) all possess a rare 3-hydroxy4-methyldecanoic acid moiety (Fig. 26) [145].
Secondary Metabolites from Marine-Derived Fungi from China
123
at a dose of 10 μM, comparable to simvastatin through the regulation of cholesterol
efflux to HDL in RAW264.7 macrophages. The mechanism of action was explained
through promotion of the target genes ABCG1 and LXRa and a decrease in critical
scavenger receptors CD36 and SR-1/SR-2 [139]. A further fungal strain of Aspergillus versicolor was isolated from the gorgonian Carijoa sp. collected from the
Weizhou coral reefs in the South China Sea. Solid rice medium fermentation of this
fungus gave a cyclic hexapeptide, aspersymmetide A (457) [140]. The fungal strain
Aspergillus terreus was isolated from the gorgonian Echinogorgia aurantiaca
collected from Sanya, Hainan Province. An unusual cyclic tetrapeptide,
asperterrestide A (458), containing anthranilic acid and 3-OH-N-Me-Phe moieties,
was obtained from fermentation of this fungus in liquid medium composed of
maltose, NaCl, sorbitol, and yeast extract. Asperterrestide A (458) exhibited cytotoxic activity against the U937 and MOLT4 human carcinoma cell lines with IC 50
values of 6.4 and 6.2 μM, respectively, and also displayed antiviral activity against
the H1N1 and H3N2 influenza viral strains, having IC 50 values of 15.0 and 8.1 μM
(Fig. 25) [141].
A strain of Aspergillus versicolor was isolated from the soft coral Cladiella
sp. collected from Lingao, Hainan Province. Three cyclopentapeptides,
versicoloritides AÀC (459–461) (Fig. 26), were obtained following fermentation
of this fungus in liquid medium composed of sea salt, sorbitol, maltose, and yeast
extract [66]. The fungus Aspergillus clavatus was isolated from the shell of the crab
Xenograpsus testudinatus collected from hydrothermal vents in Kueishantao near
Taiwan. From the mycelium and broth obtained from a cultivation of the fungus in
liquid potato medium, two anthranilic acid-containing cyclic depsipeptides,
clavatusides A and B (462 and 463), were isolated, while cultivation in a zincenriched medium yielded the cyclic pentapeptide clavatuside C (464). Clavatusides
A and B (462 and 463) suppressed the proliferation of the HepG2, SMMC-7721, and
Bel-7402 hepatocellular carcinoma cell lines in a dose- and time-dependent manner
with IC 50 values ranging between 32 and 64 μM. Clavatuside B (463) was also active
against several other human cancer cell lines including pancreatic cancer (Panc-1),
gastric cancer (MGC-803), colorectal cancer (SW-480), retinoblastoma (WERI-Rb1), and prostate cancer (PC3) cell lines in a dose-dependent manner with IC 50 values
ranging between 32 and 42 μM [142, 143].
A cyclic tetrapeptide (465), containing the unusual amino acids 3-aminoacrylic
acid and 3-methoxyanthranilic acid, was isolated from the solid rice medium fermentation of Aspergillus flavipes obtained from the gut of the marine isopod Ligia
oceanica collected in Zhoushan, Zhejiang Province [144]. A strain of Nigrospora
oryzae was obtained from the inner tissue of the sponge Phakellia fusca collected
from Yongxing Island in the South China Sea. Fermentation of this fungus in liquid
PDA medium yielded three cyclohexadepsipeptides, oryzamides AÀC (466–468),
and two isolation artifacts, oryzamides D and E (469 and 470), which are methionine
sulfoxide diastereomers. Oryzamides AÀE (466–470) all possess a rare 3-hydroxy4-methyldecanoic acid moiety (Fig. 26) [145].
Secondary Metabolites from Marine-Derived Fungi from China
123