Antimicrobial Sesquiterpenoid Derivatives and Monoterpenoids from the Deep-Sea Sediment-Derived Fungus Aspergillus versicolor SD-330

Abstract

Two new antimicrobial bisabolane-type sesquiterpenoid derivatives, ent-aspergoterpenin C (compound 1) and 7-O-methylhydroxysydonic acid (2), and two new butyrolactone-type monoterpenoids, pestalotiolactones C (3) and D (4), along with a known monoterpenoid pestalotiolactone A (5) and four known bisabolane sesquiterpenoids (6−9), were isolated and identified from the deep-sea sediment-derived fungus Aspergillus versicolor SD-330. The structures of these compounds were elucidated on the basis of spectroscopic analysis, and the absolute configurations of the new compounds 1−4 were determined by the combination of NOESY and TDDFT-ECD calculations and X-ray crystallographic analysis. Additionally, we first determined and reported the absolute configuration of the known monoterpenoid pestalotiolactone A (5) through the X-ray crystallographic experiment. All of these isolated compounds were evaluated for antimicrobial activities against human and aquatic pathogenic bacteria. Compounds 1, 2, 6 and 9 exhibited selective inhibitory activities against zoonotic pathogenic bacteria such as Escherichia coli, Edwardsiella tarda, Vibrio anguillarum and V. harveyi, with MIC values ranging from 1.0 to 8.0 μg/mL.

New Monoterpenoids and Polyketides from the Deep-Sea Sediment-Derived Fungus Aspergillus sydowii MCCC 3A00324

“…In addition, seven known compounds were established to be pestalotiolactone A ( 5 ) [ 42 , 43 ], 3,7-dihydroxy-1,9-dimethyldibenzofuran ( 6 ) [ 44 ], diorcinol ( 7 ) [ 45 ], cordyol C ( 8 ) [ 46 ], 4-(3′,4′-dihydroxyphenyl)-2-butanone ( 9 ) [ 47 ], 3,4,5-trimethoxybenzoic acid ( 10 ) [ 48 ], and 4-hydroxybenzoic acid ( 11 ) [ 49 ] on the basis of comparison of their NMR and specific rotation data with those reported in the literature.…”

Antimicrobial Secondary Metabolites from the Seawater-Derived Fungus Aspergillus sydowii SW9

“…Antimicrobial evaluation against pathogenic bacteria (Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pneumoniae) was assayed as described previously [20], with chloramphenicol as the positive control. The specific experiment was as follows: the initial cultures were maintained on Luria Broth (LB) agar plates for each pathogenic strain, picking bacterial colonies, and suspended in Mueller-Hinton broth to approximately 5 × 10 5 CFU/mL.…”

Antibacterial Alkaloids and Polyketide Derivatives from the Deep Sea-Derived Fungus Penicillium cyclopium SD-413

“…Marine sediment-derived fungi have received considerable attention as a valuable resource of bioactive metabolites with diversified chemical structures including alkaloids, peptides, polyketides, and terpenoids [1][2][3][4][5][6]. These natural products are characterized by intriguing biological properties such as anticancer, antifouling, antimicrobial, antioxidant, and antiviral activities [4][5][6][7][8][9].…”

“…In our continuing excavation to identify new bioactive metabolites from deep sea-derived fungi [7][8][9][10][11][12], the fungus Penicillium cyclopium SD-413, which was obtained from a sediment sample collected from the East China Sea, was screened out for chemical investigations. As a result, two new polyketide derivatives, 9-dehydroxysargassopenilline A (4) and 1,2-didehydropeaurantiogriseol E (5), along with seven known related metabolites (1-3 and 6-9) (Figure 1), were isolated and identified from the culture extract of the fungus.…”

“…In addition to the two new secondary metabolites (4 and 5) and three known quinazoline alkaloids (1-3), four known derivatives of polyketide (6)(7)(8)(9) were also isolated from the culture extract of the fungus P. cyclopium SD-413. By detailed spectroscopic analysis as well as comparisons with reported data, the structures of compounds 3 and 6-9 were identified as aurantiomide C (3) [17], craterellone D (6) [18], peaurantiogriseol A (7) [16], aspermytin A (8) [19], and 1-(2,8-dihydroxy-1,2,6trimethyl-1,2,6,7,8,8a-hexahydronaphthalen-1-yl)-3-hydroxy-1-propanone (9) [20], respectively.…”