| 54strains of microorganisms were screened for their capabilities to trasformechiocystic acid (EA-1). Four of them could metabolize echinocystic acid, thepreferred three species to expand foster. Seven metabolites were afforded and five ofthem were new.Pestalotiopsis microspora GU441597.1(endophytic fungus isolated from the stems ofHuperzia Serrata) was used to transform echinocystic acid (EA-1). Two productswere afforded. Their structures were elucidated as3-oxo-16α,29-dihydroxy-olean-12-en-28-oic acid (EA-2);3β,16α,29-trihydroxy-olean-12-en-28-oic acid (EA-3).Metabolite (EA-2) was a new compound.Mucor racemosus CGMCC3.0205could transform echinocystic acid (EA-1) to affordthree new compounds:3-oxo-7α,16α-dihydroxy-olean-12-en-28-oic acid (EA-4)；3-oxo-16β,19β-dihydroxy-olean-12-en-28-oic acid (EA-5)；3-oxo-7β,16β,21β-trihydroxy-olean-12-en-28-oic acid (EA-6).Biotransformation of echinocystic acid (EA-1) by fungus Helicostylum piriformeCGMCC3.0162yielded two metabolites:3β,7β,16α-trihydroxy-olean-12-en-28-oicacid (EA-7)；3β,19β-dihydroxy-olean-12-en-28-oic acid28-O-β-D-glucopyranoside(EA-8). EA-8was a new compound.Elucidation of the structures of these metabbolites was based on1D-NMR and2D-NMR and HR-MS data. |
PDF Full Text Request