Alkaloids and Polyketides from the Marine-Derived Fungus Aspergillus versicolor
- PDF / 162,240 Bytes
- 4 Pages / 594 x 792 pts Page_size
- 92 Downloads / 237 Views
ALKALOIDS AND POLYKETIDES FROM THE MARINE-DERIVED FUNGUS Aspergillus versicolor
Shuai-Shuai Zhang,1 Ao Zhu,1 Xuan Bai,2 Hua-Jie Zhu,1 and Fei Cao1*
Marine-derived fungi, which have very high medicinal value, can produce a large number of bioactive secondary metabolites [1]. Among them, previous studies showed that marine-derived Aspergillus versicolor has a wide array of bioactive natural products such as xanthones, alkaloids, cyclic peptides, and terpenes [2–5]. Our ongoing research on the EtOAc extract of the marine-derived fungus A. versicolor HBU-2017-7 indicated it has antibacterial and cytotoxic activities. Conclusively, eight compounds (1–8), including three alkaloids and five polyketides, were obtained from the fungal strain HBU-2017-7. The structures of 1–8 were identified by NMR and MS data as brevianamide K (1) [6], brevianamide R (2) [7], brevianamide Q (3) [7], 8-di-O-methylaverufin (4) [8], 1′-O-methylaverantin (5) [9], arugosin C (6) [10], sterigmatocystin (7) [11], and 5-methoxysterigmatocystin (8) [11]. Compound 2 was identified as brevianamide R by comparison of its 1H and 13C NMR spectroscopic data with those of brevianamide R reported in the literature [7]. However, the absolute configuration of brevianamide R has not been reported previously. In this paper, the absolute configuration of C-9 in 2 was determined as 9S by comparing the calculated ECD spectrum with its experimental values. Fungus Material. The fungus Aspergillus versicolor HBU-2017-7, which was collected from the Bohai Sea, was identified by ITS sequence. The strain was deposited at the Key Laboratory of Pharmaceutical Quality Control of Hebei Province Hebei University. Culture Condition. Starter cultures were maintained on PDA medium. Plugs of agar supporting mycelia growth were cut and transferred aseptically to a flask containing rice culture (100 mL seawater, 80 g rice). The flasks were then incubated at room temperature statically for 45 days. 13
O 11
15 17
N H
19
O
O
10
N HN 24
23
1
O
21
HN
N H
9
1
22
8a
8
O
R
O
9
O
2
9a
O
H3CO
2, 3
4a 4 10
N 7
6'
5 10a
H3CO
OH 4
17 18
4'
OH O
HO
11
OH
8
O
OH
OCH3
22 19
5
6
10
21
O
1'
13
O
3 7
O O
H
H
10
4' 24
OH
R 5
1 2'
14
13
3
O
3'
HO O
3'
1'
11
OH
12
1
O
OH
23
7, 8
2, 8: R = OCH3; 3: R = OH; 7: R = H
1) College of Pharmaceutical Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, P. R. China, e-mail: [email protected]; 2) Affiliated Hospital of Hebei University, Baoding, 071000, P. R. China. Published in Khimiya Prirodnykh Soedinenii, No. 5, September–October, 2020, pp. 824–826. Original article submitted August 12, 2019. 964
0009-3130/20/5605-0964 ©2020 Springer Science+Business Media, LLC
TABLE 1. Antibacterial Activities Data of Compounds 1–8 (MIC, μM) Compound
S. aureus
B. subtilis
P. aeruginosa
E. coli
C. albicans
1 2 3 7 8 Ciprofloxacin
> 25 12.5 > 25 > 25 6.13 0.312
6.13 6.13 > 25 12.5 6.13 0.625
12.5 > 25 12.5 12.5 12.5 0.625
6.13 > 25 12.
Data Loading...
