History

The aim of the study was to identify endophytic fungi from different plant sources and which one produced a high level of xanthone compound and investigate that purified xanthone’s immunosuppressant and antioxidant scavenger activity. 25 endophytic fungi were isolated from stems and leaves of healthy and mature plants of Ficus carica, Capsicum frutescens, and Chenopodium mural which were collected from Al-Qurna groves, Al-Zubair farm, and Safwan desert in Basrah province of Iraq respectively during December 2019 to February 2020. After that, fungal isolates were cultivated on semi-solid flour rice medium as fermentation medium for 40 days at 28οC to yield secondary metabolites. Then investigating crude extracts for each endophytic fungi by Gas Chromatography/MS, it is revealed that Aspergillus costaricensis (OM420244.1) extract from F. carica contains 9H-Xanthen-9-one,1-hydroxy-3,6-dimethoxy-8-methyl- with percentage 2.152% in retention time of 28.870 minutes. Purified xanthone by silica gel column and thin-layer chromatographed (TLC). Furthered characterized by LC-MS and MNR as Dothideoxanthone C16H14O5 (m/z 286.28). A significant positive correlation between Dothideoxanthone and immunosuppressant to mice splenic lymphocytes induced by LPS and Con A (IC50 14±0.49 and 11.73±0.14) respectively in comparing with cyclosporin A (IC50 7.67±0.07 and 6.91±0.08) as standard.  Also, Dothideoxanthone had significant antioxidant scavenging activity in different tests (O-phenanthroline assay, Superoxide radical, and nitric oxide (NO) scavenging activity) with IC50 (14.90±0. 65, 7.73±0.04 and 171.31±13.93) respectively in comparing with standards ascorbic acid IC50 (54.02±7.69, >200 and 70.33±5.21) and BHT IC50 (108.84±7.16, >200 and >200) respectively. The result reveals that dothideoxanthone purified from A. costaricensis secondary metabolites isolated from F. carica is found that it has moderately potent as immunosuppressant and highly potent as an antioxidant compound.