Isolation of secondary metabolites from the mangrove endophytic fungus Scopulariopsis sp.H3A2 and evaluation of their in vitro antibacterial activities
LIU Yaqi
HUANG Guozhu
CHEN Xiaorao
CAO Zhiqin
WANG Weinan
ZHENG Xikang
WU Jun
Abstract：Objective To study the secondary metabolites of Scopulariopsis sp.H3A2,an endophytic fungus isolated from mangrove trees in Malaysia.Methods Silica gel and octadecylsilane(ODS)column chromatography,as well as high-performance liquid chromatography(HPLC),were used to isolate and purify the crude extract from the solid fermentation of the rice strain.The structures of all compounds were determined by analyzing nuclear magnetic resonance(NMR)and mass spectrometry(MS)data and comparing them with literature data.Meanwhile,the antibacterial activity of the compounds against Staphylococcus aureus,Escherichia coli,Micrococcus luteus,Enterococcus faecalis,Candida albicans,and Aspergillus niger was tested by the double dilution method.Results Ten compounds were isolated from the rice solid fermentation crude extract of the strain.The structures of all compounds were determined to be 5,7-dihydroxy-3,4-dihydro-1(2H)-naphthalenone(1),2′-deoxythymidine(2),4,6,8-trihydroxytetralin-1-one(3),3,4,6,8-tetrahydroxy-3,4-dihydro-2H-naphthalen-1-one(4),6-hydroxymellein(5),cyclo(L-Leu-trans-4-hydroxy-L-Pro)(6),cyclo(L-Phe-trans-4-hydroxy-L-Pro)(7),indole-3-carboxylic acid(8),indole-3-carboxaldehyde(9),and 4-hydroxybenzaldehyde(10).The minimum inhibitory concentrations of compounds 1 to 10 are all greater than or equal to 128 mg/L.Conclusion Compounds 1-7 and 10 were isolated from the Scopulariopsis sp.for the first time,and the NMR data of compound 1 was reported for the first time.Compounds 1 to 10 showed no antibacterial activity against Staphylococcus aureus,Escherichia coli,Micrococcus luteus,Enterococcus faecalis,Candida albicans,and Aspergillus niger.
Keywords：mangroveendophytic fungisecondary metabolitesantibacterial activity
Publication Date：2025-12-30
Online Publishing Date：2025-12-11(First online date of this platform, not the publication date of the document)
Pages：7( 598-604 )