Studies On Chemical And Bioactivity Constituents From The South Sea Sponge Phyllospongia Foliascens

The ecological environment of the ocean,such as high pressure,high salinity,low temperature,hypoxia,and lack of light,makes the survival strategies and metabolic mechanisms of marine organisms more unique than those of terrestrial organisms.Therefore,marine organisms generally have complex skeleton structures,as well as natural products with various activities such as anti-tumor,antibacterial,anti-cardiovascular,anti-viral,anti-inflammatory,antioxidant,hypotensive,immune regulation and disease prevention.In addition,marine microorganisms also have the advantages of high absorption,rapid transformation,vigorous growth,rapid reproduction,strong adaptability,and sustainable utilization of natural resources.They are a new source for finding high-efficiency and low-toxic drugs or leading compounds.Sponges are a kind of multicellular animal with simple structures and diverse shapes.Their biomass accounts for about 7%of the total biomass of marine species,and they are the second-largest species.Among them,40%of marine natural products come from sponges.The sponge contains a large number of natural active products and is an important marine biological resource.At the same time,the sponge also has a high abundance and diversity of microbial communities,which is also the focus of research on the evolution of symbiotic microorganisms.There is increasing evidence that sponges are true producers of secondary metabolites.In this paper,the immersion method was used to extract the Phyllospongia foliascens collected near Yongxing Island,Xisha,South China Sea.The solvent step extraction reduced pressure column chromatography,reversed-phase ODS column chromatography,fast liquid preparative chromatography,and high-performance liquid preparative chromatography were used to extract.A total of twenty-eight monomer compounds were isolated from the total extract by various separation and purification methods.The structural types include eleven disesquiterpenes,eleven sterols,four fatty acids and two polyketides.Using nuclear magnetic resonance spectroscopy(¹H NMR,¹³C NMR,COSY,HSQC,HMBC,NOESY),infrared spectroscopy（IR）,ultraviolet spectroscopy（UV）,mass spectrometry（MS）,circular dichroism（CD）and optical rotation and other spectral analysis techniques,combined with the literature,their chemical structures were identified.Including ten new compounds:phyllofenone O（1）,phyllofenone P（2）,phyllofenone Q（3）,phyllofenone R（4）,phyllofenone S（5）,phyllofenone T（6）,phyllofenone U（7）,phyllofenone V（8）,phyllofenone W（9）,phyllofolactone X（10）and 18 known compounds:phyllofenone B（11）,cholestroal（12）,5α,8α-epidio-xycholest-6-en-3β-ol（13）,cholest-5-ene-3β,7α-diol（14）,tetradecanoic acid（15）,3-nitrothiophene（16）,methyl-dihydrofuran-2-acetate（17）,dibutyl phthalate（18）,2-oxybis-di-tert-butylbenzene（19）,（R）-2-ethylhexyl-1,2,3-triazole-4-carboxylate（20）,cholesta-5,7-dien-3β-ol（21）,ergosta-5,7,24-trien-3β-ol（22）,ergosta-5,7-dien-3β-ol（23）,（24E）-stigmasta-5,7,24-trien-3β-ol（24）,stigmasta-5,7-dien-3β-ol（25）,5α,6α-epoxystigmasta-7-en-3β-ol（26）,5α,6α-epoxycholest-7,22-dien-3β-ol（27）,5α,6α-epoxyergosta-7-en-3β-ol（28）.The absolute configurations of some new compounds were determined by J value comparison,CD and optical rotation comparison.Among them,new compounds 1 and 2 are rare 6/6/6/5-ring scalarane-type frameworks,and compounds 22-28 are isolated from this genus sponge for the first time.A preliminary biological activity evaluation of some of the isolated compounds was carried out.In antibacterial activity,nordisesquiterpenoids containing 6/6/6/5 rings showed significant activity against the seven tested bacteria,with MIC values ranging from 2-32μg/m L,and most of the rest The antibacterial activity of the compounds was weak or even inactive,and the MIC values were all greater than 32μg/m L.Among the cytotoxic activities,compound 22 has moderate cytotoxic activity against the six tumor cells tested,with IC₅₀ values ranging from 10.3-44.2μM;compounds 26 and 27 also have a certain inhibitory effect on the six tumor cells tested,the IC₅₀ values ranged from3.9-65.3μM,the other compounds did not show obvious cytotoxic activity,and the IC₅₀values were all greater than 80μM.In this paper,the chemical constituents of P.foliascens were studied by using a variety of modern chromatographic and spectroscopic methods.In addition,this project adopts the molecular network GNPS strategy based on secondary mass spectrometry to systematically study and analyze the chemical constituents of a large number of scalarane-type disesquiterpenoids,and speculate new compounds with similar structures,and complete complex molecular structures quickly.The analysis provides clues for the later directional separation to obtain new structural molecules with significant activity.The research on this subject shows the diversity of marine biochemical components,and also provides a new research direction for finding marine bioactive components with potential medicinal value.