toudsolla@gmail.com; Tél : (00228) 98353119 RESUME L'utilisation des composts de déchets en agriculture est l'une des voies principales dans la restauration de la fertilité des terres dégradées. Cependant, les effets d'un compost dépendent fortement de sa nature chimique et des conditions environnementales. Afin de mieux comprendre le mécanisme d'action des composts de déchets sur les propriétés chimiques du sol et la solubilité des ions, cinq types de composts de déchets ont été testés selon un dispositif en blocs de Fischer repartis en trois répétitions par traitements. Les résultats obtenus révèlent que les composts de déchets ont en général élevé le pH du sol de 2,13 unités et la conductivité électrique de 1301,9 µS/cm. Les traitements à engrais synthétique NPK ont par contre réduit le pH de 0,51 unité. A l'exception du traitement à compost de déchets agroalimentaires, les traitements à compost ont en général réduit le potentiel Redox contrairement aux traitements témoin et à engrais synthétiques. Ainsi, les traitements à engrais synthétique et à compost de déchets agroalimentaires sous déficit hydrique présentent respectivement des potentiels de 307,5 mV et 265 mV contre 262,5 mV pour le témoin absolu sous déficit hydrique. L'étude de la fraction hydrosoluble des éléments minéraux montre que la solubilité des cations essentiels (Ca, Mg et K) est liée fortement à leur concentration dans le substrat de culture contrairement aux éléments traces métallique dont la solubilité dépend essentiellement du pH et du potentiel Redox. Par ailleurs, le déficit hydrique a entraîné l'élévation de la conductivité électrique chez les traitements à composts. Ces résultats seront utilisés dans la phytorémédiation des sols pollués.

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Well established as source of bioactive compounds, medicinal plants have long been used in treatment of human ailments. The validation of traditional use of medicinal plants can be achieved by screening a collection of extracts for bioactivity using in vitro, in cellulo and even in vivo assays. The results of this work are consistent with the traditional use of the various parts of Ficus sur to cure hepatic pain, cardiovascular and neurodegenerative diseases, cancer, and diabetes. Although the bark extract is more active than the extracts of the other organs, it would be better to use the leaves to preserve the plant, as these contain all the metabolites present in the bark and much more. Please cite this paper as:Saloufou KI, Boyode P, Simalou O, Eloh K, Idoh K, Melila M, et al. Chemical composition and antioxidant activities of different parts of Ficus sur.Introduction: Ficus sur is a plant widely used in traditional pharmacopoeia in Togo. So, this study aimed the assessment of antioxidant properties and identification of some compounds from the ethanolic extracts of different parts of the plant (leaves, fruits, roots, and barks). Methods: The phenolic and flavonoid contents of the ethanolic extracts of different organs of Ficus sur were assessed using conventional known methods. The DPPH radical scavenging and the ferric-reducing antioxidant power (FRAP) assays were used to highlight the antioxidant activities. The different extract samples were also analysed by liquid chromatography coupled to a quadrupole-time of flight mass detector (ESI-QTOF). Results: Total phenolic contents (TPCs) for 1 mg of dry extract ranged from 489.40 ± 7.48 μg GAE (gallic acid equivalents) for the bark to 62.34 ± 2.66 μg GAE for unripe fruits. The bark exhibited the highest flavonoid content, which was closed to 90.20 ± 3.72 μg QE (quercetin equivalents)/mg of dry extract. The radical scavenging activities of the bark and unripe fruits were 56.50 ± 0.29 and 7.3 ± 0.30 μg QE/mg of dry extract, respectively. In the same order, the FRAP values of the two organs were 104.57 ± 4.75 and 19.61 ± 0.22 μmol FeSO 4 Eq/mg of dry extract. Many compounds including notoginsenoside R10; 4' ,5,7-trihydroxyflavan-3-ol; catechin; and boviquinone 4 were identified. Conclusion: The various organs of Ficus sur are a source of bioactive compounds especially phenolic compounds and flavonoids with antioxidant activity.

In sub-Saharan Africa, soil degradation and recurrent droughts are major obstacles to a sustainable agriculture. This study aimed at investigating the effect of compost addition to soil on proline content and activities of the antioxidant enzymes [catalase (CAT), ascorbate peroxidase (APX)] in maize plants, under drought stress conditions. The test was carried out in 20L plastic pots containing either sandy soil or sandy soil with the fertilizer, under natural conditions. The water deficit was induced at male blooming and milky grain stages. Plant irrigation was done by successive weighing of the pots during which the control is reduced to the same weight corresponding to 70% of the useful water reserve (UWR), while the stressed treatment maintains the water content at 30% of the UWR for 10 days. At the end of the stress period, the proline content, the CAT and APX activities in the leaves were determined through a spectrophotometry. The results show an important accumulation of proline and increase in enzymatic activity induced by water deficit in plants grown on compost (p = 0.00000 at p < 0.05). This study provides evidence for a beneficial effect of compost application in enhancing drought tolerance of maize.Keywords: Drought stress; compost; proline; antioxidant enzymes; Zea mays L.

Holarrhena floribunda trunk bark exhibited antihypertensive and antioxidant properties, supporting its use for the treatment of hypertension in traditional medicine. So, more investigations are needed for identification of the active compounds in Holarrhena floribunda ethanolic extract involved in antioxidant and antihypertensive activities.