Four chlorinated depsidones from a seaweed-derived strain of Aspergillus unguis and their new biological activities.
Four chlorinated depsidones (two reported for the second time (1 and 2) and two known (3 and 4)) were isolated from a seaweed-derived Aspergillus unguis strain. Their structures were spectroscopically elucidated. Compounds 1, 3 and 4 strongly inhibited methicillin-resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentrations (MICs) of 2, 2 and 4 μg/mL and killed Artemia larva with LC50 of 4.1, 1.7 and 2.8 μg/mL, respectively. Besides, in DNA-damaging test, they also selectively inhibited a DNA repair capacity-defective Escherichia coli strain AB3027(-) (MICs: 2, 32 and 4 μg/mL, respectively) compared with the wild-type strain AB1157(+) (MICs: over 512, over 512 and 256 μg/mL, respectively). Furthermore, compound 1 also strongly inhibited cancer cell line A-549 (IC50: 0.5 μg/mL). The above-mentioned bioactivities were newly reported for compound 1. In contrast, compound 2 did not exhibit significant activity. The structure-activity relationship indicated that a complete lactone ring may be important.
a School of Environmental and Chemical Engineering, Dalian Jiaotong University , Dalian , P.R. China.
Yi
Y
Zhang
Jun
J
Mu
Yan
Y
Feng
Lixue
L
Wen
Jinyuan
J
Han
D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001156:Artemia / Q000187:drug effects; D001230:Aspergillus / Q000737:chemistry*; D004249:DNA Damage / Q000187:drug effects; D053630:Depsides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D007783:Lactones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D012624:Seaweed / Q000382:microbiology*; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D053630:Depsides; D006843:Hydrocarbons, Chlorinated; D007783:Lactones; C000875:depsidone