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Yu ZQ, Ren H, Guo XW, Yang GG, Wu J, Xi JM, Xiang XY, Fang J, Wu QX. Targeted isolation, identification, and antioxidant evaluation of aromatic polyketides from a plant-derived fungus Ophiobolus cirsii LZU-1509. Fitoterapia 2024:105884. [PMID: 38460855 DOI: 10.1016/j.fitote.2024.105884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/27/2024] [Accepted: 03/03/2024] [Indexed: 03/11/2024]
Abstract
There are >350 species of the Ophiobolus genus, which is not yet very well-known and lacks research reports on secondary metabolites. Three new 3,4-benzofuran polyketides 1-3, a new 3,4-benzofuran polyketide racemate 4, two new pairs of polyketide enantiomers (±)-5 and (±)-7, two new acetophenone derivatives 6 and 8, and three novel 1,4-dioxane aromatic polyketides 9-11, were isolated from a fungus Ophiobolus cirsii LZU-1509 derived from an important medicinal and economic crop Anaphalis lactea. The isolation was guided by LC-MS/MS-based GNPS molecular networking analysis. The planar structures and relative configurations were mainly elucidated by NMR and HR-ESI-MS data. Their absolute configurations were determined by using X-ray diffraction analysis and via comparing computational and experimental ECD, NMR, and specific optical rotation data. 9 possesses an unreported 5/6/6/6/5 five-ring framework with a 1,4-dioxane, and 10 and 11 feature unprecedented 6/6/6/5 and 6/6/5/6 four-ring frames containing a 1,4-dioxane. The biosynthetic pathways of 9-11 were proposed. 1-11 were nontoxic in HT-1080 and HepG2 tumor cells at a concentration of 20 μM, whereas 3 and 5 exerted higher antioxidant properties in the hydrogen peroxide-stimulated model in the neuron-like PC12 cells. They could be potential antioxidant agents for neuroprotection.
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Affiliation(s)
- Zhen-Qing Yu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Hao Ren
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Xiao-Wei Guo
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Ge-Ge Yang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Jia Wu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Jun-Min Xi
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Xin-Yu Xiang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Jianguo Fang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
| | - Quan-Xiang Wu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China.
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Guo XW, Yu ZQ, Xi J, Ren H, Xiang XY, Wu J, Fang J, Wu QX. Isolation and Identification of Novel Antioxidant Polyketides from an Endophytic Fungus Ophiobolus cirsii LZU-1509. J Agric Food Chem 2023; 71:1593-1606. [PMID: 36634077 DOI: 10.1021/acs.jafc.2c07386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Sixteen new polyketides, ophicirsins A-P (1-16), including four novel carbon skeletons (5-9, 14, 15, and 16), were isolated from the extract of an endophytic fungus Ophiobolus cirsii LZU-1509. The unique frameworks of ophicirsin N (14) and O (15) feature a different cyclic ether connected with an aromatic ring system. Ophicirsin P (16) is characterized by the unprecedented heterozygote of a polyketide and an alkaloid. The absolute stereochemistries of those polyketides were characterized via single-crystal X-ray diffraction analysis and the experimental and computational electric circular dichroism spectra comparison. Theoretical reaction pathways in the fermentation to generate different novel skeletons starting from acetyl CoA and malonyl CoA helped to assign their structures. Compounds 1-16 appear almost nontoxic in HepG2 and HT-1080 tumor cells. Their antioxidant effects were further evaluated, and 15 exhibits an excellent protection activity in hydrogen peroxide-stimulated oxidative damage in neuron-like PC12 cells via screening all compounds. Moreover, 15 displays a greater ability to scavenge the 2,2-diphenyl-1-picrylhydrazyl free radicals than resveratrol. Taken together, these findings suggest that the novel polyketides could serve as potential antioxidant agents for neuroprotection.
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Affiliation(s)
- Xiao-Wei Guo
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Zhen-Qing Yu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Junmin Xi
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Hao Ren
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Xin-Yu Xiang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Jia Wu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Jianguo Fang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
- School of Chemistry and Chemical Engineering, Nanjing University of Science & Technology, Nanjing, Jiangsu 210094, China
| | - Quan-Xiang Wu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
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