MANGANESE’S EFFECT IN THE SHEET APOPLAST HIBISCUS SABDARIFFA L. VAR SABDARIFFA FOR 10 DAYS

Young shoots of sorrel leaves (Hibiscus sabdariffa L. var sabdariffa) were cultured in chamber for 10 days. They were submitted to the effect of manganese concentration 0,3μM per day for studying the accumulation and the toxicity of the ore in the apoplast of leaves. The results show that Mn is accumulated in the leaves during the 10 days of experiment; the number of brown spots and callose synthesis increase during the 10 days of experience. In the leaves, the antioxidants activities Guaiacol-POD and NADP-POD are high during exposure to Mn. They are raised from fifth to ninth days for Guaicol-POD and the fifth to the seventh day of the ninth and tenth days for the NADP-POD. The activity of Guaiacol-POD and NADP-POD is evaluated to monitor their detoxification response to Mn exposure level in the leave. This correlates with the reduction in the rate of H2O2 and NADH. The Leaves of sorrel shoots have the ability to accumulate and tolerate 0,3uM Mn during 10 days of exposure by inducing the synthesis of callose and controlling the rate of Guaiacol-POD and NADP-POD

Polymerization Degree of Phytochelatin in Contaminated Soil Phytoremediation of Manganese in Hibiscus Sabdariffa Linn Var Sabdariffa

The aim of this study is to determine the usefulness of roselle (Hibiscus sabdariffa L. var sabdariffa), and its polymerization degree of phytochelatins (PCs) for contaminated soil Mn phytoremediation. Sorrel plants grow in three highly contaminated soils Mn (4μM, 6μM and 8μM) in control conditions. Roselle accumulates large amounts of Mn in the leaves in the various contaminated environments Mn. The removal rate of absorption in the higher Mn was observed in the medium 8μM Mn. In parallel, the middle 4μM Mn showed the lowest Mn extraction rate. Induced oxidative stress due to the Mn content, generates the highest level in ascorbate 8μM Mn. The medium 8μM Mn shows an induction of 9 to 16 times the amount of γ-glutamylcysteine and against a low induction of γ- glutamylcysteine in the medium 4μM Mn. Accordingly, the total content phytochelatin (PC) was 7-9 times higher 8μM Mn. In addition, PCs high polymerization degree were observed in 8μM Mn (PC4, PC6 and PC7), while PC2 and PC3 occurred in 4μM Mn and 6μM Mn only. The correlation analysis shows that 8μM Mn phytoremediation capacity is associated with the PCs synthesis and their polymerization degree is high

ANTIOXYDANTS ET PHYTOCHELATINES DANS LA TOLERANCE ET L'ACCUMULATION DU MANGANESE CHEZ L'HIBISCUS SABDARIFFA LINN.

After 12 days of culture seeds roselle (Hibiscus sabdariffa L.) growth chamber, seedlings are subject to the effect of manganese concentration (2,9μM) to study the accumulation of Mn and its toxicity for 24 hours (1 day). The results show that Mn accumulates extensively in the shoot than in the roots, photosynthetic pigments (chloro (a) and carotenoids) and the enzyme system (SOD, CAT and GPOX) increase during 24 hours of experience. In shoot, SOD and CAT enzyme activity is higher than that APX, GR and GPOX. In roots, SOD enzyme activity and GPOX is higher than APX, GR and CAT. The amount of glutathione (GSH) and phytochelatin (PCs) are measured to monitor their responses detoxification under exposure levels of Mn in the plant. The maximum synthesis PCs rise to 24 hours of exposure to Mn. This correlates with reduced GSH. This shows that a protective mechanism that chelate excess Mn out of the metabolic center is set up by the plant. Hibiscus sabdariffa Linn therefore has the ability to accumulate and tolerate concentrations of Mn in the first hour of exposure by controlling the rate of GSH and PCs

ANTIOXYDANTS ET PHYTOCHELATINES DANS LA TOLERANCE ET L'ACCUMULATION DU MANGANESE CHEZ L'HIBISCUS SABDARIFFA LINN.

After 12 days of culture seeds roselle (Hibiscus sabdariffa L.) growth chamber, seedlings are subject to the effect of manganese concentration (2,9μM) to study the accumulation of Mn and its toxicity for 24 hours (1 day). The results show that Mn accumulates extensively in the shoot than in the roots, photosynthetic pigments (chloro (a) and carotenoids) and the enzyme system (SOD, CAT and GPOX) increase during 24 hours of experience. In shoot, SOD and CAT enzyme activity is higher than that APX, GR and GPOX. In roots, SOD enzyme activity and GPOX is higher than APX, GR and CAT. The amount of glutathione (GSH) and phytochelatin (PCs) are measured to monitor their responses detoxification under exposure levels of Mn in the plant. The maximum synthesis PCs rise to 24 hours of exposure to Mn. This correlates with reduced GSH. This shows that a protective mechanism that chelate excess Mn out of the metabolic center is set up by the plant. Hibiscus sabdariffa Linn therefore has the ability to accumulate and tolerate concentrations of Mn in the first hour of exposure by controlling the rate of GSH and PCs

Repartition Des Glossines Dans La Province De L’ogooue Ivindo Ancien Foyer De Trypanosomose Humaine Africaine

In Gabon, the situation of Human African Trypanosomosis (HAT) remains unclear. In addition, several historical foci existing in many provinces have not been explored for over 15 years. Yet many studies have shown that this country has to offer favorable ecosystems for the development of tsetse major vectors of HAT. To verify a risk of transmission of sleeping sickness, a tsetse inventory was conducted in the province of Ogooué Ivindo historic home of HAT. Vavoua and Nzi traps were placed in four characteristic habitats of the province: National Park Ivindo, Zadié Village, Forest of Zadié and baï (clearing) of Momba. A total of 2383 flies were captured: 1680 flies in the clearing of Momba, 437 flies in the primary forest Zadié, 139 in the National Park Ivindo and 12 in Zadié village. Moreover, these flies were divided into 7 species Glossina frezili, Glossina fusca congolensis, Glossina nashi, Glossina palpalis palpalis, Glossina tabaniformis, Glossina fuscipes fuscipes and Glossina tachinoides. Glossina palpalis palpalis (46%) was the most abundant species followed by Glossina fusca congolensis (21%) and Glossina nashi (16%). Glossina fuscipes fuscipes (6%), Glossina frezili (4%), Glossina tabaniformis (4%) and Glossina tachinoides (3%) were the least caught species. These results have shown that the province of Ogooué Ivindo still remains infested by tsetse flies. Also, further study monitoring these insects is essential to clarify the epidemiological importance of these vectors on human health in this province

Etude De Quelques Caracteristiques Physicochimiques Et Biochimiques De Wavé-fortex Un Complement Alimentaire Naturel Du Gabon

Wavé-fortex is a dietary supplement designed to Gabon, to fight against the problems of malnutrition and undernourishment. It would also contain diuretic properties, purgative, antimicrobial, aphrodisiac, influenza, regulating blood pressure, reducing overweight and stimulating sperm production. This work was carried out to study the physicochemical and biochemical characteristics of this health food. The results revealed that Wavé-fortex was heavily dehydrated and contained 6.27% of crude ash and 11.32% of total gross fibers. The mineral level, Wavé-fortex contains 1.27% of calcium, 0.09% of iron, 0.37% of magnesium, 0.87% of potassium and 0.01% of zinc. Biochemical analyzes showed that this functional food contained 45.69% of carbohydrates, 26.01% of protein and 4.67% of fat. This gives it an energy value of 3.55 kcal / g of dry matter. Wavé-fortex is an acidic product (pH 4.02) with high levels of vitamin A (2.38%), vitamin C (1.93%) and phenolic compounds (11.83%). The different levels of these compounds are capable of validating the various nutritional properties attributed to this food powder

Évaluation de la composition spécifique des glossines, vectrices de la Trypanosomose Humaine Africaine, dans la région de Ndendé au sud du Gabon

Objectifs: Afin d’évaluer la composition spécifique des glossines dans les biotopes savanicoles et forestiers, une étude entomologique a été réalisée sur ces insectes dans la région de Ndendé (province de la Ngounié), ancien foyer de la Trypanosomose Humaine Africaine (THA) pour identifier les sites potentiels de transmission de cette parasitose.Méthodologie et résultats: Un total de 14 pièges vavoua a été utilisé dont 7 pièges placés le long des cours d’eau présents dans la galerie forestière et 7 autres en savane proche des villages, du 23 octobre au 7 novembre 2015. Au total, 697 glossines ont été capturées (DAP=3,32 glossines/piège/jour). La plus forte abondance des glossines a été obtenue en forêt avec 678 spécimens. Cependant, ces glossines ont été faiblement capturées en savane (19 spécimens). Ces glossines se répartissent en quatre espèces dont Glossina fuscipes fuscipes, Glossina frezili, Glossina nashi et Glossina palpalis palpalis. G. fuscipes fuscipes (95%) a été l’espèce la plus abondante alors que G. frezili (1%), G. nashi (2%) et G. palpalis palpalis (2%) ont été très faiblement capturées.Conclusion et application: Cette étude a permis d’identifier dans la région de Ndendé, quatre espèces de glossines qui vivent en sympatrie. Par ailleurs, la forte abondance de G. fuscipes fuscipes et la présence de G. palpalis palpalis, vecteurs de la THA dans les différents biotopes prospectés, avec une forte prédominance enforêt, suggèrent une existence probable d’un risque de transmission des trypanosomes dans la région de Ndendé. Par conséquent, le biotope forestier serait une zone prioritaire pour une lutte antivectorielle afin de limiter les risques de transmission de cette parasitose. Aussi, ces résultats invitent à la réalisation des travaux plus détaillés visant à identifier la dynamique spatio-temporelle des glossines et leur rôle dans la transmission éventuelle de la THA dans la région de Ndendé au sud du Gabon.Mots-clés: Trypanosomose humaine africaine, glossine, composition spécifique, savane, forêt, GabonEnglish AbstractObjectives: In order to assess the species composition of tsetse flies among savannah and forested biotopes, an entomological survey was conducted on these insects in the Ndende region (province of Ngounié), ancient focus of Human African Trypanosomiasis (HAT) for identifying the potential sites of the HAT transmission.Methodology and results: A total of 14 Vavoua traps was used with 7 traps installed along the rivers present in the forest gallery and 7 others in the savannah near the villages. The study was done from 23rd October to 7th November 2015. In total, 697 tsetse flies were captured (ADT=3.32 tsetse flies/trap/day). The highest abundance of tsetse flies was found in the forest with 678 specimens, while the lowest abundance was observed in the savannah with 19 specimens. The identified tsetse flies are G. fuscipes fuscipes, G. nashi, G. frezili and G. palpalis palpalis. G. fuscipes fuscipes (95%) was the most abundant species. Conversely, G. frezili (1%), G. nashi (2%) and G. palpalis palpalis (2%) were less in number.Conclusion and application: The results of this study showed the presence of four tsetse flies species, biological vectors of HAT, in the Ndendé region. The high abundance of G. fuscipes fuscipes and the presence of G. palpalis palpalis, vectors of HAT, in different savannah and forested biotopes, with strong predominance inforest, suggest a probable risk of transmission of trypanosomes in the Ndende region. Thus, the forested biotope would be the priority areas for implementing a vector control in order to limit the risks of HAT transmission. Therefore, these results require studies aiming at identifying spatial and temporal dynamics of tsetse flies and their role in the eventual transmission of HAT in the Ndendé region, southern of Gabon.Keywords: Human African trypanosomiasis, tsetse fly, species composition, savannah, forest, Gabo

Mise Au Point D’un Protocole De Sterilisation D’explants Nodaux D’alchornea Cordifolia Avec De L’acide Triclororoisocyanurique

Trichloroisocyanuric acid is a swimming pool disinfectant and is readily accessible. As a result, there is the need to use it as a substitute for conventional disinfectants in in vitro culture. Nodal explants of Alchornea cordifolia, harvested in a natural environment, have been rinsed abundantly with Dettol under running water. Then it was soaked in Talo Plus (550 g/l carbendazim and 100 g/l Chlorothalonil) at 5 ml/liter, which is a broad spectrum fungicide. After then, it was immersed in 70% alcohol for 10 minutes before being soaked in different solutions of trichloroisocyanuric acid to: 6, 4, 3, 2, 1, 0.3, 0.1, and 0.08%. The explants were disinfected completely of all contaminating bacterial and fungal exogenous. This was after a treatment in solutions of acidic trichloroisocyanurique of 6 to 0.08%. The results showed that the losses of active chlorine remained low during storage at temperatures of 4 to 18 ± 2°C. They reach only 5.29% after 72 hours. At room temperature of 27 ± 2 ° C, these losses are more than 30% after three days. Concentrations of 0.1 to 0.3% are effective for the disinfection of explants. This protocol of explants disinfection in vitro culture could therefore be advantageously substituted using the hypochlorite of calcium or the chloride of mercury

Etude de la Relation entre l’abondance des grands mammifères frugivores et celle des fruits dans le Parc National de Moukalaba-Doudou, Gabon

Au Gabon, les travaux portant sur les relations plantes animaux demeurent encore très lacunaires. Pourtant, cette connaissance est indispensable dans la compréhension des fonctionnements des écosystèmes forestiers, mais aussi sur le comportement alimentaire des mammifères. C’est dans ce cadre qu’une étude sur l’abondance des mammifères frugivores et celles des fruits a été conduite dans le Parc National de Moukalaba Doudou. Les données sur l’abondance des mammifères ont été recueillies à l’aide des caméras pièges, le long de 11 transects de janvier 2012 à janvier 2014. Quant aux fruits, ils ont été récoltés le long de ces transects sur une bande de 1 m de large de part et d’autre du transect. Au total, 2492 fruits repartis en 100 espèces ont été recensés au cours de cette étude. Le nombre de fruits recensés a varié en fonction des biotopes prospectés et des mois. Les caméras pièges ont permis d’identifier dix espèces de mammifères frugivores présents dans cette zone. Le test de corrélation P de Pearson (R= 0,2 ; df= 10, P= 0,5) a montré que la variation entre l’abondance des mammifères et celle des fruits reste indépendante.Mots clés : Abondance, fruits, mammifères, Parc National Moukalaba-Doudou, caméra piège, Gabon

Ecological Aspects of Tabanids (Diptera: Tabanidae) in a Gabonese Cattle Ranch

To embark on an anti-vectorial fight against mechanical vectors of animal trypanosomosis, investigations were undertaken in order to determine the abundance, species diversity and daily activity of tabanids in a cattle ranch in Gabon. The nzi and vavoua traps were used to catch tabanids in three divisions of this ranch. In this study, 616 tabanids were captured: 349 (56.66%) in Division 1, 226 (36.69%) in Division 2 and 41 (6.66%) in Division 3. In the first Division, T. taeniola was the most abundant species with an Apparent Density (ADT) of 2.2, followed by H. pluvialis (ADT = 1.05). In the second Division, H. pluvialis was most abundant with ADT of 1.6, followed by T. taeniola (ADT = 0.38). In the last Division, the most abundant species was H. pluvialis (ADT = 0.15). Comparing the relative abundance of catches with sites (Divisions), we realized that there was no statistically significant difference in catches with trapping sites. It was noticed that Division 3 recorded the highest diversity index values. We realized that the nzi trap recorded higher tabanid catches than the vavoua trap. The diurnal activity rhythm of the most frequent species encountered slightly differed with prospection sites