The Secondary Metabolites From Two Marine Fungi And Their Chemical Ecological Effects

The study focused on Penicillium dipodomyicola and Aspergillus versicolor to research their secondarymetabolites. Chromatographic process were used to obtain pure compounds produced by DJ008, and MS andNMR were applied to identify their structure. Medium formula and culture time optimization were used asproduction increasing tools. Metabolic pathway of DJ013were regulated by2-hexyl-4-pentynoic acid（37.5mg/L）, a kind of HDACi. The pure compound obtaining and identifing were carried out by chromatographicprocess, MS and NMR. This study was composed of four parts.1. Separation and screening of strains. Five marine fungi strains were isolated from sediments taken from EastIsland. Two strains were chosed by combining chemical screening and epigenetic screening, that were DJ008andDJ013. After morphological identification and18S rDNA sequence aligment, these two fungi were identified asPenicillium dipodomyicola and Aspergillus versicolor.2. Secondary metabolites of DJ008’s obtaining. Silica gel normal phase chromatography was used to divide thecrude extracts into different polarity, and other purification methods were applied to pure the target again. Thetarget compound was finally charaterized as flufuran. Cytotoxic activity tests showed that flufuran had noinhibition against human cancer cell lines HL60and A549.3. Study on fermentation technology. Medium formula optimization and culture time optimization were carriedout. The optimal cultivation condition was potato extract10g/L, soluble starch20g/L, temperature25℃,rotation speed150rpm and fermented for12days. The maximum production of flufuran can reach1.91g/L.4. regulation of secondary metabolitical pathways of DJ013. The exact of DJ013culture with2-hexyl-4-pentynoicacid (37.5mg/L) was detected by HPLC. The experimental proup can yield a compond, and was indentified ascurvularin by MS and NMR. This compound showed no inhibition towards HL60and A549.In this study, the prodution of flufuran was enhanced by medium formula and incubation time optimization, whichcan be used as guidance in other optimization experiments. HDACi2-hexyl-4-pentynoic acid was applied toregulate the metabolitical pathways of DJ013, making the occurrence of curvularin, which was of greatsignificance in changing gene expression with chemical methods.