Fobofou Phd Thesis V6 19042016
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Metabolomic Analysis, Isolation, Characterization and Synthesis of Bioactive Compounds from Hypericum species (Hypericaceae ) Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften (Dr. rer. nat.) der Naturwissenschaftlichen Fakultät II Chemie, Physik und Mathematik der Martin-Luther-Universität Halle-Wittenberg vorgelegt von Herrn M.Sc. Serge Alain Fobofou Tanemossu geb. am 09.10.1986 in Nkongsamba, Kamerun The work presented in this thesis was designed by Prof. Dr. Ludger A. Wessjohann, Dr. Katrin Franke, and myself and performed by me (M.Sc. S. A. Fobofou) at the Department of Bioorganic Chemistry of the Leibniz Institute of Plant Biochemistry (IPB) in cooperation with the Martin- Luther University Halle-Wittenberg. Supervisor: Prof. Dr. Ludger A. Wessjohann “This dissertation is submitted as a cumulative thesis according to the guidelines provided by the PhD-program of the Martin-Luther University Halle-Wittenberg. The thesis comprises seven peer-reviewed and original research papers (five already published and two in preparation), which cover the majority of first author’s research work during the course of his PhD.” Serge Alain Fobofou T. “Gedruck mit Unterstützung des Deutschen Akademischen Austauschdienstes“ 1. Gutachter: Prof. Dr. Ludger Wessjohann 2. Gutachter: Prof. Dr. Ludger Beerhues Tag der Verteidigung: 14. Dezember 2016 No part of this dissertation may be reproduced without written consent of the author, supervisor or IPB The Lord is my strength and my shield; my heart trusted in Him and I am helped (Psalm 28:7). “Many times a day I realize how much my outer and inner life is built upon the labors of people, both living and dead, and how earnestly I must exert myself in order to give in return how much I have received.” Albert Einstein To the Almighty God, my family and friends PhD thesis_Fobofou Table of contents Table of contents Acknowledgements 6 List of abbreviations 8 1. General introduction 9 2. NMR and LC-MS based metabolome analyses of plant extracts for natural product class 24 mapping and prioritization in new natural product discovery: the example of St. John’s wort ( Hypericum ) 3. Tricyclic acylphloroglucinols from Hypericum lanceolatum and regioselective 49 synthesis of selancins A and B 4. Isolation and anticancer, antihelminthic, and antiviral (HIV) activity of 75 acylphloroglucinols, and regioselective synthesis of empetrifranzinans from Hypericum roeperianum 5. Rare biscoumarin derivatives and flavonoids from Hypericum roeperianum : 98 bichromonol, the first example of anti-HIV biscoumarin from the genus Hypericum 6. Prenylated phenyl polyketides and acylphloroglucinols from Hypericum peplidifolium 122 7. New source report: chemical constituents of Psorospermum densipunctatum 138 (Hypericaceae) 8. General discussion and perspectives of ongoing and future research 146 Summary 152 Zusammenfassung 153 Curriculum vitae 154 Author’s declaration about his contribution to publications on which the thesis is based 157 Certificates (Urkunden) 159 Declaration (Erklärung) 165 PhD thesis_Fobofou Acknowledgements Acknowledgements I wish to thank all the people who directly or indirectly contributed to the realization of this work. Especially, I am sincerely indebted to Prof. Dr. Ludger Wessjohann, who despite his numerous commitments accepted to supervise my PhD thesis and hosted me at the Leibniz Institute of Plant Biochemistry (IPB) as a DAAD doctoral fellow. His significant contribution during the design of my PhD project made me knowledgeable about the current trends of modern natural products chemistry, including metabolomics. His advices, encouragements, suggestions, and support were valuable for a successful scientific career and beyond. Dr. Katrin Franke, my advisor and research project leader, sincerely deserves my highest thankfulness for her guidance, great support, fruitful discussions, and truthful encouragement. I also wish to express my profound gratitude to Dr. Arnold Norbert for his mentorship, guidance, encouragement, and personal concern about the success of my thesis and future plans thereafter. This work would have not been possible without the scientific and technical support from many people of the IPB: Dr. Andrea Porzel, who taught me how to handle the NMR machine, measured some of my samples, and provide critical discussions for structure determinations and NMR metabolomics. This is extended to Dres. Jürgen Schmidt and Gerd Balcke, our experts of MS. I also extent my gratitude to Dres. Steffen Neumann, Tilo Lübken, Mohamed Farag, and Mr. Robert Berger for help and valuable discussions about R scripts and metabolomics in general. Dr. Wolfgang Brandt is acknowledged for CD spectra calculations and scientific discussions. Especial thanks go to Prof. Dr. Bernhard Westermann for his great encouragement and fruitful discussions during the preparation of this thesis. Nicole Hünecke, Anja Ehrlich, and Gudrun Hahn are acknowledged for their help in growing C. elegans , cytotoxic assays, and optical and NMR measurements, respectively. Mrs. Ines Stein is acknowledged for her help with administrative and residence permit matters. I thank my colleagues Alexander Otto (who performed the antifungal assays), Ramona Heinke, Annika Denkert, and Haider Sultani as well as all the other members of NWC for the good atmosphere, friendship, help, and discussions. Thanks are extended to Prof. Paolo La Colla and Dr. Giuseppina Sanna (University of Cagliari, Italy) for their support and collaboration for anti-HIV (MT-4, HIV-1, and HIV-1 resistant strains) and antibacterial (against resistant strains) assays. I do not forget my DAAD RISE interns and mentees Chelsea Harmon (MTSU, USA) and Megan Wancura (Smith College, USA) for their great laboratory assistance in investigating H. peplidifolium and H. frondosum , cultural exchange, 6 PhD thesis_Fobofou Acknowledgements and for editing my manuscripts for common English language mistakes during their summer internships at the IPB. I also wish to acknowledge all my former lecturers at the University of Dschang (Cameroon), especially my former M.Sc. supervisors Profs. Dres. Pierre Tane and Wabo Kamdem Hippolyte for their teaching and mentorship. I am grateful to the DAAD committee members, referees and staff, especially to my fellowship advisor Ms. Christine Butter (now called Mrs. Eschweiler), who made me get to Germany and constantly provided the support I needed. In addition, I also wish to thank the people without whom I could not have been what I am. Special acknowledgements go to my late mother Mrs. Madeleine Tsasse for her steadfast and unconditional love, prayers, support, and encouragement. Whenever I doubted, she had been there to say with a trustful heart: “You will arrive in Jesus’s name.” I am also grateful to my father Mr. Tanemossu, sisters, and brothers for their constant love, supports, patience, prayers, and encouragement. Especial thanks go to my elder brother Dr. Sylvain V.T. Sob for his great advices. I am profoundly thankful to all my fellow Christians, especially to Apostle Simon P. Bayama E. and wife for their great spiritual support and life changing teaching in heart, so that I may know the mystery of God’s love and mercy, namely, Christ, in whom are hidden all the treasures of life, success, peace of heart, wisdom, and knowledge, etc. Especial thanks go to my friends, brothers and sisters in Christ of the Evangeliumsgemeinde in Halle-Germany for their prayers. Finally, financial support from the DAAD for a doctoral grant and two RISE fellowships is highly appreciated. I am grateful to the IPB for supporting the lab costs and travel to conferences. I acknowledge the Lindau Nobel Laureate and Falling Walls Foundations which, through their respective fellowships, gave me the unique opportunities to present my ideas and PhD thesis results at their respective meetings and also to learn about cutting-edge science, share, and meet with some of the brightest and most esteemed minds on the planet. 7 PhD thesis_Fobofou Acknowledgements List of abbreviations [α] Specific rotation LC Liquid chromatography AIDS Acquired immune deficiency syndrome LC-MS Liquid chromatography/mass spectrometry bs Broad signal m Multiplet CC Column chromatography MIC Minimum inhibitory concentration CCID 50 (50%) Cell Culture Infective Dose m.p. Melting point CD Circular dichroism MS Mass spectrometry CFU Colony-forming unit MS n Tandem mass spectrometry CoA Coenzyme A MVDA Multivariate data analysis COSY Correlated spectroscopy m/z Mass-to-charge-ratio d Doublet NMR Nuclear magnetic resonance dd Doublet of doublet NOESY Nuclear Overhauser effect spectroscopy ddd Doublet of doublet of doublet NNRTI Non-nucleoside/nucleotide reverse transcriptase inhibitor DEPT Distortionless enhancement by polarization NRTI Nucleoside/nucleotide reverse transcriptase transfer inhibitor DFT Density functional theory PCA Principal component analysis DMAPP Dimethylallyl pyrophosphate PAL Phenylalanine ammonia lyase DMSO Dimethylsulfoxide PI Protease inhibitor DMSO-d6 Deuterated dimethylsulfoxide PMS Phenazine methosulfate DSM Deutsche Sammlung von Mikroorganismen ppm Parts per million EDDA Ethylenediamine diacetate rel. int. Relative intensity EIMS Electron impact mass spectrum ROESY Rotational frame Overhauser effect spectroscopy ESIMS Electron spray ionization mass RPMI Roswell Park Memorial Institute spectrum FTICR Fourier transform ion cyclotron resonance s Singlet GC Gas chromatography t Triplet GPP Geranyl pyrophosphate TAL Tyrosine ammonia lyase HCA Hierarchical