Phytochemical Study of Plants Used Tradi- Tionally for Cosmetics and Medicine in the Is
Total Page：16
File Type：pdf, Size：1020Kb
COMMUNAUTÉ FRANÇAISE DE BELGIQUE UNIVERSITÉ DE LIÈGE – GEMBLOUX AGRO-BIO TECH Phytochemical study of plants used tradi- tionally for cosmetics and medicine in the is- land of Mayotte. Matthew Saive Dissertation originale présentée (ou essai présenté) en vue de l’obtention du grade de doc- teur en sciences agronomiques et ingénierie biologique Promoteur : Marie-Laure Fauconnier Année civile : 2021 © Matthew Saive 28/04/2021 Saive Matthew, (2021). Phytochemical study of plants used traditionally for cos- metics and medicine in the island of Mayotte. (PhD thesis). University of Liège – Gembloux Agro-Bio Tech. 213p., 23 fig., 9 table Summary: The Indian ocean is one of the biggest source of botanical diversity in the world, 25% of the world’s flora can be found in those islands. In addition, people living in that area, have been using what nature has to offer to treat themselves for centuries. In this work we focused on the Comoros archipelago and more precisely on the island of Mayotte. The socio-economic situation of the area has been precarious since the end of the Ylang-ylang (Cananga odorata (Lam.) Hook.f. & Thomson) in- dustry. The aim of this thesis is to provide the inhabitants with an analysis of plant species with the potential for the development of local cosmetic products. Through the analysis of the traditional knowledge we were hoping to find the ideal species for this project. First, a preliminary study was conducted leading to the identification of more than 200 different species which could be useful. Following this first work, an infield ethnobotanical study was conducted allowing for the identification of 69 spe- cies which were interesting. By cross referencing the previously gathered information 21 different species were identified for collection and the analysis so as to validate their real biological activity: the lipoxygenase inhibition potential, the tyrosinase in- hibition potential and the DPPH (2,2-diphenyl-1-picrylhydrazyl) reduction potential. The most active species then underwent a selection process based on current knowledge-to-date and availability. Following this selection, we focused on the roots of the litchi plant (Litchi chinensis Sonn.). The last step of this work consisted of the identification of the compound responsible for the observed activities. This was achieved by submitting the crude extract of L. chinensis to a bio-guided fractionation until only a single compound remained. The purified compound then went through the following molecular identification process: UV, IR, MS, RMN and colorimetric analysis. Finally, these process allowed us to identify a compound from the polyphe- nol family: cinnamtannin D2 (CAS number : 97233-47-1). Saive Matthew, (2021). Etude phytochimique de plantes utilisées en cosmétique et médecine traditionnelle à Mayotte. (Thèse de doctorat). University of Liège – Gem- bloux Agro-Bio Tech. 213p., 23 fig., 9 tables Résumé: L’océan Indien est une des plus grande source de variété botanique du monde, 25% de la flore mondiale peut être trouvée dans les îles qui s’y trouvent. De plus les peuples qui habitent ces régions utilisent ce que la nature a à leur offrir pour se soigner depuis des centaines d’années. Dans ce travail nous nous somme focalisés sur l’archipel des Comores et plus précisément, l’île de Mayotte. Cette région est en situation socio-économique précaire depuis le déclin de l’industrie de l’Ylang-ylang (Cananga odorata (Lam.) Hook.f. & Thomson). Cette thèse a pour but de fournir aux habitants une analyse des espèces végétales potentiellement valorisables pour le dé- veloppement de produits cosmétiques. En analysant les savoirs traditionnels, nous avions l’espoir de trouver l’espèce idéale pour ce projet. Dans un premier temps, une étude préliminaire a été réalisée, à la suite de laquelle plus de 200 espèces différentes ont été identifiées. Ce premier travail fut suivi d’une étude de terrain, à l’issue de laquelle 69 espèces intéressantes ont pu être identifiées. En croisant les informations obtenues lors des 2 premières étapes de ce travail, un total de 21 espèces ont été col- lectées afin d’être analysées pour cibler les échantillons présentant des activités bio- logiques réelles. Celles-ci étaient les suivantes : l’évaluation du pouvoir d’inhibition de la lipoxygénase, l’évaluation du pouvoir d’inhibition de la tyrosinase et l’évalua- tion du pouvoir de réduction du DPPH (2,2-diphenyl-1-picrylhydrazyl). Les espèces présentant les meilleures activités ont fait l’objet d’une sélection basée sur l’état des connaissances les concernant et leur disponibilité. A l’issue de cette sélection, nous avons décidé de nous focaliser sur les racines de Litchi (Litchi chinensis Sonn.). La dernière étape de ce travail a consisté en l’identification d’un composé responsable des activités observées. Pour se faire l’extrait brut de racine de L. chinensis a été sou- mis à un fractionnement bio-guidé jusqu’à l’obtention d’un composé unique. Celui-ci a ensuite été soumis aux tests d’identification moléculaire suivants : UV, IR, MS, RMN et colorimétrique. Le résultat de ces analyses nous a permis d’identifier un com- posé issu de la famille des polyphénols, le cinnamtannin D2 (numéro CAS : 97233- 47-1). Acknowledgments At the end of this work I would like to thank: My supervisors, Professor Marie-Laure Fauconnier and Professor Michel Frederich for their availability, their motivation and their patience. I would also like to thank the team from the General and organic chemistry labora- tory from Gembloux and the team from the pharmacognosy department of Liege University. Their good mood and knowledge allowed me to move forward when times were tough. With a special thanks to Manon Genva, Thibaut Istasse, Dany Trisman and Ewa Ciekiewicz for their help regarding the sample’s characterization I would also like to give a special thank you to the people in Mayotte who helped me, guided me around, and all in all allowed for this work to be possible. More specifically the people from the “Conservatoire botanic national du Masca- rin” (CBNM) from Mayotte. The people from the Coconi’s college and from the ag- ricultural station from Dembeni who gave me access to their infrastructure and shared their knowledge regarding the species identified throughout this work. I would like to give a special thank-you to Hassani Soulaimana who was crazy enough to start this project and to accompany me through the first steps of its reali- zation. I would also like to give a special thanks to Nathalie Le Mest who helped me get in touch with the informants in order to conduct the ethnobotanical work. And of course, I would like to thank all the informant for accepting to share their knowledge with me. I would like to thank Professor François Malaisse for his help regarding the botan- ical aspect of this work. And a special thanks to Professor Yves Brostaux who helped me sort out the mas- sive amount of information gathered during this work. I would like to thank Chloe Maes for her contribution to this work during her mas- ter’s thesis. Last but not least I would like to thank my family and friends who were there dur- ing the good times and the bad times and who never stopped believing that I could do it. With a special mention to my mother who went through the whole English correc- tion process since I started writing articles. “It does not matter how slowly you go so long as you do not stop.” Confucius Acknowledgments ....................................................................................................... 5 List of figures and tables .......................................................................................... 11 GENERAL INTRODUCTION.............................................................................. 15 1. Global context of the study .......................................................................... 17 2. Economic situation of the study area ........................................................... 17 3. Political and social status of the study area ................................................. 18 4. Geography of the study area ........................................................................ 20 5. Climate of the study area ............................................................................. 21 6. Flora of the study area ................................................................................. 23 7. Key concepts ................................................................................................ 25 7.1. Ethnobotany, ethnopharmacology and phytochemistry ............................... 25 8. Thesis organization ...................................................................................... 25 8.1. Objective of the first article – what is known .............................................. 25 8.2. Objective of the second article – let’s ask the ones who know.................... 26 8.3. Objective of the third article – evaluation of the activities .......................... 26 8.4. Objective of the fourth article – molecular identification ............................ 26 BIBLIOGRAPHIC REVIEW ............................................................................... 27 Plants used in traditional medicine in the Comoros archipelago: a review .............. 31 1. Introduction .................................................................................................. 33 1.1. Context and study area ................................................................................. 35 1.2. Geography