Study Of The Metabolites Of Marine-Derived Penicillium Sp.ZZ380 And Their Bioactivities

Marine-associated fungi,especially the species from genus Penmcillium are one of the important resources of marine bioactive substances.OSMAC(One Strain,Many Compounds)strategy through changing culture conditions of microorganisms can explore the biosynthetic potential of marine microorganisms to obtain secondary metabolites with more diverse structures and better bioactivity.In this dissertation,the OSMAC strategy by changing the components of culture media and co-culture was used to largely culture strain Penicillium sp.ZZ380 three times,respectively,and the chemical ingredients of the cultures and their antimicrobial and antiglioma activities were investigated.By using modern chromatographic separation technologies,a total of forty-eight compounds were isolated from the three different cultures of strain ZZ380.The structures of the isolated compounds were elucidated by a combination of NMR and HRMS spectroscopical analyses,Mosher's method,ECD calculation,and X-ray diffraction,resulting in the discovery of ten novel alkaloids of pyrrospirones C-J(1-8),penicipyrrodiether A(9),and penicipyrroether A(28).Pyrrospirone J(8),penicipyrrodiether A(9),and penicipyrroether A(28)possess unique structures and each of them represents the first compound of its structural class.Particularly,penicipyrrodiether A(9)has a new skeleton structure with more complicated fused rings.The plausible biosynthetic pathways of these new alkaloids were also proposed in this study.All forty-eight compounds were evaluated for their antimicrobial and antiglioma activities.The antimicrobial results showed that all ten new alkaloids had activity with varying degrees in inhibiting the growth of methicillin-resistant Staphylococcus arreus and Escherichia coli,of which pyrrospirones C(1)?F(4)?I(7)and penicipyrroether A(28)showed stronger activities with MIC values of 4.0-5.0,2.0-3.0,2.0-4.0,and 1.7-3.0 ?g/mL,respectively.In addition,pyrrospirone D(2)and penicipyrrodiether A(9)also had strong antibacterial activity against MRS A with MIC values of 3.0 ?g/mL for 2 and 5.0?g/mL for 9.The results from antiglioma assay demonstrated that all ten new alkaloids also had activity with different degrees against the proliferation of human glioma U87MG and U251 cells with IC50 values of 1.06-26.64 ?M and pyrrospirone G(5)and penicipyrroether A(28)were more active with IC50 values of 1.06-1.28?M and 1.64-5.50 ?M,respectively,equivalent to(or slightly stronger than)the activity of the positive control doxorubicin.Interestingly,cytotoxicity of pyrrospirone G(5)and penicipyrroether A(28)against normal human astrocytes were weak,of which pyrrospirone G(5)showed very high selectivity index of 32.6-39.4In summary,this study used the OSMAC strategy to culture the marine-derived Penicillium sp.7.ZZ380,resulting in the discovery of ten novel alkaloids,of which several compounds showed good antibacterial and antiglioma activities.Especially,pyrrospirone G(5)possesses the characteristics of strongest antiglioma activity and highest selectivity index and has value and application potential for further investigation.