Purification Of Antifungal Active Compound And Effects On Artificial Cell-membrane Of Trichoderma Aureoviride

Potential biocontrol strain of Trichoderma aureoviride was studied. Based on this, separation and purificationt of antifugi active compound(Ta-1)in metabolite was researched to implement structural identification. In order to separate polarity metabolite of Trichoderma aureoviride and decide the process of separation and purification of active compound, butyl alcohol extraction, silicon gel column chromatography, preparative chromatography and separation ( Rf=0.70 ) and gel column chromatography were all adopted.The inspected concentration of analytical HPLC is 99%.The maximum ultraviolet absorption peak of the active compound is located in 224nm. The active substance contains-C6H6,–CH3,-CH2,-OH and -C=O, through IR and 1H, 13C NMR analysis, and its molecular weight was 826 by FAB-MS. Compared with other antifungal compounds obtained from Trichoderma spp., molecular weight of active compound separated from T. aureoviride was the biggest and maybe a new agricultural antibiotic.Taking 1-hexadecylamine and 1-bromohexadecane as starting materials, two lipids were synthesized. After seven steps, including substitution and condensation reaction, the desired products, cationic peptide lipid N,N-dihexadecyl-Nα-[6-(trimethylammonio)hexanoyl]alaninamide bromide(N⁺C₅Ala₂C₁₆) and lipid N,N-dihexadecyl-Nα-[6-(trimethylammonio)hexanoyl]asparaginase bromide(N₊C₅Asp₂C₁₆)were obtained, the yields was 4.4% and 3.5% separately. Hereinto N₊C₅Asp₂C₁₆ is a new synthetic compound.The relationships between biology moleculers such as cholesterol, cholic acid or its derivant, metabolite of Trichoderma aureoviride and phosphatidylcholine, peptide lipid(N⁺C₅Ala₂C₁₆,N₊C₅Asp₂C₁₆)were researched under the buffer system of HEPES pH7.0, the effects of biology moleculers with different concentration on natural and artifical membrane were also studied with the change of temperature. As the concentration of cholic acid increased, the fluidity of gel peptide lipid membrane was larger, but as the concentration of cholesterol increased, the fluidity of liquid crystal peptide lipid membrane was smaller. It was no effect.of cholic acid concentration on fluidity, as the concentration of cholesterol increased, the fluidity of gel DMPC was increased, but the fluidity of liquid crystal DMPC was decreased. Either DMPC or lipid structure was damaged and the phase transition point was lossed under low concentrations (5%) of Ta-1。...