丹东近海真菌Aspergillus pseudoglaucus次级代谢产物的研究

Study on the secondary metabolites from Aspergillus pseudoglaucus derived from offshore mud in Dandong

目的研究海洋来源真菌假灰绿曲霉Aspergillus pseudoglaucus次级代谢产物的化学成分及其抗氧化活性。方法摇床发酵后,采用硅胶柱层析、LH20凝胶色谱和半制备高效液相色谱等方法,对假灰绿曲霉发酵总浸膏进行分离纯化;利用核磁共振(NMR)、质谱(MS)、旋光和单晶X-ray衍射技术结合文献报道数据确定化合物结构,并对其抗氧化活性进行测定。结果从假灰绿曲霉中共分离鉴定了10个单体化合物:ent-3β-hydroxy8α,11-drimanediol(1)、3,4-dihydroxy-5-methoxyphthalaldehyde(2)、fomecin B(3)、3,4-二羟基苯甲酸(4)、(3R,10S,6E)-2,6,10-trimethyldodeca-6,11-diene-2,3,10-triol(5)、(10R,2E,6E)-3,7,11-trimethyldodeca-2,6-diene1,10,11-triol(6)、methyl(10R,2E,6E)-10,11-dihydroxy-3,7,11-trimethyl-2,6-dodecadieoate(7)、环(酪氨酸-亮氨酸)(8)、环(苯丙氨酸-酪氨酸)(9)和环(丙氨酸-苯丙氨酸)(10)。结论从假灰绿曲霉中分离得到化合物1~10,其中1为新化合物,2为新天然产物。化合物2和3清除DPPH自由基的IC50分别为2.42和1.86μg/mL。

Objective To explore the secondary metabolites and their antioxidant activity of the fungus Aspergillus pseudoglaucus derived from offshore mud in Dandong for the first time.Methods Silica gel column chromatography,LH20 column chromatography and semi-preparative HPLC were employed to isolate and purify the secondary metabolites from the extract of A.pseudoglaucus.The structures of the isolated compounds were elucidated by extensive NMR,MS,optical rotation and X-ray diffraction analyses,as well as comparisons with the data of literatures.Results Ten compounds were obtained and identified as ent-3β-hydroxy-8α,11-drimanediol(1),3,4-dihydroxy-5-methoxyphthalaldehyde(2),fomecin B(3),3,4-dihydroxy benzoic acid(4),(3R,10S,6E)-2,6,10-trimethyldodeca-6,11-diene-2,3,10-triol(5),(10R,2E,6E)-3,7,11-trimethyl-dodeca-2,6-diene-1,10,11-triol(6),methyl(10R,2E,6E)-10,11-dihydroxy3,7,11-trimethyl-2,6-dodecadieoate(7),cyclo(Tyr-Leu)(8),cyclo(Phe-Tyr)(9)and cyclo(Ala-Phe)(10).Conclusion Ten compounds were isolated from the culture of A.pseudoglaucus,including one new drimanetype sesquiterpenoid(1),named ent-3β-hydroxy-8α,11-drimanediol,along with one new naturally occurring product(2).Compound 2 and 3 exhibited strong radical scavenging activities against DPPH with IC50 values of 2.42 and 1.86μg/mL,respectively.