A detailed chemical investigation of the secondary metabolites produced by the endophytic fungus Xylaria sp.isolated from the stems of Isodon sculponeatus afforded six new compounds,xylariahgins A-F(1-6),two new natur...A detailed chemical investigation of the secondary metabolites produced by the endophytic fungus Xylaria sp.isolated from the stems of Isodon sculponeatus afforded six new compounds,xylariahgins A-F(1-6),two new natural products(7 and 8),along with two known compounds(9 and 10)(Fig.1).The structures of all compounds were unambiguously established by analyzing their spectroscopic data or referring to pertinent literature.Compounds 1-8 were tested for their cytotoxic activity against five human tumor cell lines.展开更多
Three previously undescribed cytochalasins,named xylariasins A‒C(1‒3),together with six known ones(4‒9)were iso-lated from Xylaria sp.CFL5,an endophytic fungus of Cephalotaxus fortunei.The chemical structures of all n...Three previously undescribed cytochalasins,named xylariasins A‒C(1‒3),together with six known ones(4‒9)were iso-lated from Xylaria sp.CFL5,an endophytic fungus of Cephalotaxus fortunei.The chemical structures of all new compounds were elucidated on the basis of extensive spectroscopic data analyses and electronic circular dichroism calculation,as well as optical rotation calculation.Biological activities of compounds 1,4‒9 were evaluated,including cytotoxic,LAG3/MHC II binding inhibition and LAG3/FGL1 binding inhibition activities.Compounds 6 and 9 possessed cytotoxicity against AGS cells at 5μM,with inhibition rates of 94%and 64%,respectively.In addition,all tested isolates,except compound 6,exhibited obvious inhibitory activity against the interaction of both LAG3/MHC II and LAG3/FGL1.Compounds 1,5,7,and 8 inhibited LAG3/MHC II with IC50 values ranging from 2.37 to 4.74μM.Meanwhile,the IC50 values of compounds 1,7,and 8 against LAG3/FGL1 were 11.78,4.39,and 7.45μM,respectively.展开更多
The fungus Xylaria sp.KYJ-15 was isolated from Illigera celebica.Based on the one strain many compounds(OSMAC)strategy,the strain was fermented on potato and rice solid media,respectively.As a result,two novel steroid...The fungus Xylaria sp.KYJ-15 was isolated from Illigera celebica.Based on the one strain many compounds(OSMAC)strategy,the strain was fermented on potato and rice solid media,respectively.As a result,two novel steroids,xylarsteroids A(1)and B(2),which are the first examples of C28-steroid with an unusualβ-andγ-lactone ring,respectively,along with two new dihydroisocoumarin glycosides,xylarglycosides A(3)and B(4),were identified.Their structures were elucidated by spectroscopic methods,X-ray diffraction and electronic circular dichroism(ECD)experiments.All isolated compounds were evaluated for cytotoxicity,DPPH radical scavenging activity,acetylcholinesterase inhibitory and antimicrobial effect.Compound 1 exhibited potent AChE inhibitory activity with an IC50 value of 2.61±0.05μmol·L^(−1).Theβ-lactone ring unit of 1 is critical for its AChE inhibitory activity.The finding was further confirmed through exploring the interaction of 1 with AChE by molecular docking.In addition,both compounds 1 and 2 exhibited obvious antibacterial activity against Bacillus subtilis with a minimum inhibitory concentration(MIC)of 2μg·mL^(−1).Compounds 3 and 4 exhibited antibacterial activities against Staphylococcus aureus with MICs of 4 and 2μg·mL^(−1),respectively,which also exhibited DPPH radical scavenging activity comparable to the positive control with IC50 values of 9.2±0.03 and 13.3±0.01μmol·L^(−1),respectively.展开更多
基金supported financially by the National Natural Science Foundation of China(81673329 and 21322204).
文摘A detailed chemical investigation of the secondary metabolites produced by the endophytic fungus Xylaria sp.isolated from the stems of Isodon sculponeatus afforded six new compounds,xylariahgins A-F(1-6),two new natural products(7 and 8),along with two known compounds(9 and 10)(Fig.1).The structures of all compounds were unambiguously established by analyzing their spectroscopic data or referring to pertinent literature.Compounds 1-8 were tested for their cytotoxic activity against five human tumor cell lines.
基金supported financially by the National Natural Science Foundation of China(No.21778027)the Natural Science Foundation of Gansu Province(No.18JR4RA003).
文摘Three previously undescribed cytochalasins,named xylariasins A‒C(1‒3),together with six known ones(4‒9)were iso-lated from Xylaria sp.CFL5,an endophytic fungus of Cephalotaxus fortunei.The chemical structures of all new compounds were elucidated on the basis of extensive spectroscopic data analyses and electronic circular dichroism calculation,as well as optical rotation calculation.Biological activities of compounds 1,4‒9 were evaluated,including cytotoxic,LAG3/MHC II binding inhibition and LAG3/FGL1 binding inhibition activities.Compounds 6 and 9 possessed cytotoxicity against AGS cells at 5μM,with inhibition rates of 94%and 64%,respectively.In addition,all tested isolates,except compound 6,exhibited obvious inhibitory activity against the interaction of both LAG3/MHC II and LAG3/FGL1.Compounds 1,5,7,and 8 inhibited LAG3/MHC II with IC50 values ranging from 2.37 to 4.74μM.Meanwhile,the IC50 values of compounds 1,7,and 8 against LAG3/FGL1 were 11.78,4.39,and 7.45μM,respectively.
文摘The fungus Xylaria sp.KYJ-15 was isolated from Illigera celebica.Based on the one strain many compounds(OSMAC)strategy,the strain was fermented on potato and rice solid media,respectively.As a result,two novel steroids,xylarsteroids A(1)and B(2),which are the first examples of C28-steroid with an unusualβ-andγ-lactone ring,respectively,along with two new dihydroisocoumarin glycosides,xylarglycosides A(3)and B(4),were identified.Their structures were elucidated by spectroscopic methods,X-ray diffraction and electronic circular dichroism(ECD)experiments.All isolated compounds were evaluated for cytotoxicity,DPPH radical scavenging activity,acetylcholinesterase inhibitory and antimicrobial effect.Compound 1 exhibited potent AChE inhibitory activity with an IC50 value of 2.61±0.05μmol·L^(−1).Theβ-lactone ring unit of 1 is critical for its AChE inhibitory activity.The finding was further confirmed through exploring the interaction of 1 with AChE by molecular docking.In addition,both compounds 1 and 2 exhibited obvious antibacterial activity against Bacillus subtilis with a minimum inhibitory concentration(MIC)of 2μg·mL^(−1).Compounds 3 and 4 exhibited antibacterial activities against Staphylococcus aureus with MICs of 4 and 2μg·mL^(−1),respectively,which also exhibited DPPH radical scavenging activity comparable to the positive control with IC50 values of 9.2±0.03 and 13.3±0.01μmol·L^(−1),respectively.
