Comprehensive Analysis of Secondary Metabolites in Usnea longissima (Lichenized Ascomycetes, Parmeliaceae) Using UPLC-ESI-QTOF-MS/MS and Pro-Apoptotic Activity of Barbatic Acid

Molecules

AshokK Tiwari¹  V.S. Phani Babu²  Bandi Siva²  Joel Boustie²  V.Lakshma Nayak³  K.Suresh Babu⁴  Vemireddy Sravanthi⁴  S.Divya Reddy⁴  Katragunta Kumar⁴  P. Shashikala⁵  CH.V. Rao⁶  B. Sridhar⁷ 

[1] Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, Telangana, India;Traditional Knowledge, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 007, Telangana, India;;Centre for NMR &;Centre for Natural Products &Division of Applied Biology, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 007, Telangana, India;Organic Synthesis and Process Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, Telangana, India;Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)—UMR 6226, F-35000 Rennes, France;

关键词: lichen;    U. longissima;    parmeliaceae;    UPLC-ESI-QTOF-MS/MS;    cytotoxic activity;    cell cycle studies;   

DOI  :  10.3390/molecules24122270

来源: DOAJ

【 摘 要 】

Considering the importance of ultra-performance liquid chromatography-electrospray ionization-quadrupole time of flight-tandem mass spectrometry (UPLC-ESI-QTOF-MS/MS) hyphenated techniques for analysis of secondary metabolites from crude extracts, the present study was aimed at identification of secondary metabolites in acetone extract of the lichen Usnea longissima. From our study, 19 compounds were tentatively identified through comparison of exact molecular masses from their MS/MS spectra, mass fragmentation studies and comparison with literature data. In addition, potent cytotoxic activity of U. longissima extract prompted us to isolate four compounds, 18R-hydroxy-dihydroalloprotolichesterinic acid (19), neuropogolic acid (20), barbatic acid (21), and usnic acid (22) from this extract which were adequately identified through mass spectrometry and NMR spectroscopy. All four compounds displayed cytotoxic activity. Barbatic acid (21) manifested doxorubicin equivalent activity against A549 lung cancer cell line with IC₅₀ of 1.78 µM and strong G0/G1 accumulation of cells. Poly ADP-ribose polymerase (PARP) cleavage confirmed that it induced cytotoxic activity via apoptosis. Finally, our work has discerned the depside, barbatic acid (21) from crude extract as a candidate anti-cancer molecule, which induces cell death by stepping up apoptosis.

【 授权许可】

Unknown