Plant Functional Types

Cahiers de Topologie et Géométrie …, 1978

© Andrée C. Ehresmann et les auteurs, 1978, tous droits réservés. L'accès aux archives de la revue « Cahiers de topologie et géométrie différentielle catégoriques » implique l'accord avec les conditions générales d'utilisation (http://www.numdam.org/legal.php). Toute uti- ...

Malgré leur rôle primordial dans les écosystèmes, les insectes, qui représentent les trois quarts des espèces animales identifiées, sont encore mal connus. Leur relation avec le règne végétal et l'espèce humaine, que ce soit comme compétiteurs au niveau des cultures ou comme auxiliaires, notamment par la pollinisation, revêt pourtant une importance majeure.

Albertisia cordifolia and Albertisia scandens are medicinal plants of Menispermaceae family, used in traditional medicine in Côte d'Ivoire. Both species were evaluated in vitro for antioxidant activity and contents of total polyphenols, flavonoids and condensed tannins. In the present study, six extracts (aqueous, ethyl acetate and ethanolic) were prepared from the leaves of A. cordifolia and the whole plant of A. scandens. The antioxidant assays were performed using the DPPH free radical scavenging and FRAP tests. Total polyphenols, flavonoids and condensed tannins were determined by spectrophotocolorimetric method. The results revealed that the yields of extraction are between 4.69-12.27%. The percentages of DPPH inhibition were between 33.84 and 69.21% while ascorbic acid and trolox gave 93.66% and 59.77% respectively. The IC50 values ranged from 20 to 280 μg ml-1 for DPPH. The ethyl acetate extract of A. cordifolia was the most active (IC50 = 20 μg ml-1 ) compared to the other extracts and trolox (28 μg ml-1 ). The antioxidant capacities (DPPH) varied between 1.90 and 7.18 mg ET g -1MS. For FRAP, the extracts showed a dose-dependent activity with antioxidant capacities between 0.80 and 2.71 mg ET g -1MS. The best iron reducing powers were obtained for the aqueous extract of A. scandens (2.71 ± 0.59 mg ET g -1MS) and ethanolic extract of A. cordifolia. These results show that these two species may play a role in the prevention of oxidative stress related diseases.

2015

Il conviendrait d'adopter le point de vue des plantes pour mesurer à quel point celles-ci ont tiré profit de leur mise en culture.

International Journal of Advanced Research (IJAR), 2019

In addition to metabolic diseases, microbial pathologies often characterized by resistance and multiresistance phenomena of certain strains with known reference molecules, constitute a real public health problem in the world as a result of the number of deaths caused each year by these pathologies. The purpose of this work is to evaluate the antioxidant and antimicrobial potential of aqueous extracts of Alchornea floribunda and Brideliaferruginea. The phytochemical composition of the extracts was determined by the calorimetric and differential method. The antioxidant activity was evaluated by the antiradical activity of the radical DPPH. Also, antimicrobial activity was determined by the well method in agar and determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. The results of the phytochemical screening reveal a wealth of phytomolecules with antimicrobial properties such as polyphenols, terpenes, flavonoids, tannins and alkaloids. Also, they emphasize that both extracts have antioxidant activities. However, the average antioxidant activity of the extract of Alchornea floribunda is greater than that of Brideliaferruginea. This activity is comparable to that of gallic acid and ascorbic acid in the DPPH free radical scavenging assay. The study of the antimicrobial activity of these two plants revealed a significant antibacterial activity with respect to several bacterial strains responsible for infantile diarrhea, namely: Shigellasonnei, Shigella spp., Yersinia pestis, Raoultellaornithinilytica, Escherichia vulneris, Salmonella choleraesuis, Escherichia coli, as well as a remarkable yeast antifungal activity (Candidaspp PV, Candida albicansbucal, Candida albicans PV).

HAL (Le Centre pour la Communication Scientifique Directe), 2021

Ce rapport est le résultat d'un travail effectué par un élève-ingénieur de deuxième année. Ce document est tel qu'il a été remis par l'élève ingénieur et ne comporte aucune correction ni commentaire de l'ENSEGID. Ce rapport ne doit donc être considéré que comme un exercice de formation. Je tiens à remercier, en premier lieu, mon maître de stage Guillaume Charrier, qui n'a pas été avare d'enseignements, pour sa disponibilité, sa confiance et sa patience. Je remercie également Maximilien Larter et Georges Kunstler pour leur aide et leurs conseils avisés. J'adresse mes remerciements à Katline Charra-Vaskou et à Mahaut Van Rooij pour m'avoir initié à la recherche expérimentale et à Christophe Serre pour l'appui technique et l'éternelle lutte contre les fuites. Un grand merci également à tous ceux que j'ai croisé, brièvement ou non, et sans qui ce stage n'aurait pas eu la même saveur : les stagiaires Marie Melesse, Line-Anaïs Robin, Angélique Galery, Mathilde Scheuber, Corentin Meunier, Flore Ploquin, Maylis Urtebise, Chelton Desarmes, les doctorants Marylou Mantova, Tsiky Adriantelomanana et Arnoul Van Rooij, ainsi que Cyril Bozonnet, post-doctorant. Enfin, je tiens à remercier toute l'équipe du PIAF pour leur accueil chaleureux et de m'avoir conforté dans mon projet futur qui est de faire de la recherche. L'équipe MEA, au sein de laquelle j'ai été accueillie, a pour sujet d'étude l'arbre et sa résistance aux stress environnementaux saisonniers tels que le gel et la sécheresse. Ces travaux de recherche s'inscrivent également dans un contexte de bouleversement des paramètres environnementaux dû au changement climatique.

2013

The carob plant is considered as one of the fruit and forester tree that has the greatest potential of valorization since all the parts of this plant can be used in several food and cosmetic applications. The carob is cultivated in several areas of lebanon but few studies are available on the ways of valorization and the functional and structural properties of the different fractions of this tree (seeds and pods). Thus, in view to develop a strategy aims to promote and contribute to a better valorization and management of this renewable resource, we undertook in this thesis of work devoted to the characterization and the evaluation of nutritive and functional properties of the carob pods resulting from several lebanese areas. This work focused particularly on the morphological and physicochemical characterization of the pods and the purified fraction of gum. These gums were the subject of a thorough study relating to their rheological behavior and the relation between this behavior,...