NUTRITIONAL PROSPECTS, ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES OF SOME FOOD PLANTS CONSUMED BY WILD MANDRILL ( MANDRILLUS SPHINX ) POPULATION FROM LÉKÉDI PARK (BAKOUMBA, GABON).

bactericidal effects. This study showed that vegetables from mandrill diet constitute good nutritional sources of nutrients and mineral compounds. Some plants will be also good natural antioxidants sources and antibacterial usable in human health. Thus, investigations of mandrill diet will constitute the good sources of nutrients and antinutritional compounds to improvement of nutrition, health and an approach for drugs discovery. Phytochemical tests the dry extracts (ethanolic, bioactive compounds was realized using with small modifications Qualitative analysis tests were realized for the presence of chemical as sterols, terpenoids, tannins, polyphenols, flavonoids, quinones and saponins. The alkaloids were tested by the measure total amount of tannins (1994) with small modifications. Aliquots of 250 μl of extract (1 mg/mL) were added at 250 of μl ammonium citrate ferric reagent (3.5g/L) more 250 μl of ammonia (20%, 8g/L) and 1200 μl of H 2 O. After 10 min of incubation at room temperature (20°C), the absorbances were read at 525 nm. All tests were carried out in triplicate and results were expressed as Tannic acid equivalent (EAT). The AAI of the extracts were ranged between 0.34 ± 2.7 and 5.19 ± 3.0. The highest AAI values have been obtained with fruits of two Aframomum species (A. cf polyanthum (5.19 ± 3.0) and A. alboviolaceum (4.16 ± 0.2)), fruits of Pseudospondias longifolia (4.02 ± 2.5), Chrysophyllum lacourtianum (3.50 ± 2.6) and Landolphia mannii (3.08 ± 0.0) and can be compared to AAI of Vitamin C (10.22 ± 0.9) and BHA (3.54 ± 6.93). The lowest values have recorded with fruits of Antrocaryon klaineanum, Uapaca guineensis and Pentaclethra macrophylla (0.34 ± 2.7, 0.56 ± 1.1 and 0.81 ± 0.3 resp.).

Research on wild vegetables established that several vegetables supply significant quantities of essential nutrients to the body and, assist in the maintenance of health and prevention of diseases. This study consisted to evaluated nutritional and pharmacological potentials of some wild vegetables from Mandrillus sphinx diet. Vegetables species selected according to their consumption frequencies and ethnopharmacological uses by local population, were therefore subjected to nutritional and pharmacological analyses.
Proximate nutrients values showed that fruits and leaves from mandrill diet present the high values in crude protein, fats and carbohydrate. Results showed also high mineral amounts were also obtained with the majority of plants eaten. Phytochemical and pharmacological analyses have shown the highest content of secondary compounds had ranged between 0.06 ± 1.18 and 44.46 ± 0.10g EAG/100g of dried matter (total phenols compounds amount), Antinutritional compounds amounts varies between 0.005 ± 2.1 and 28.15 ± 0.22 g EAT/100g DM (tannins) and 0.021±0.29 and 11.45 ±0.03 g EQ/100g DM (flavonoids). Our results showed also the good antioxidant activity of some plant organs consumed by both two populations human and mandrill such as Aframomum cf. polyanthum, A. alboviolaceum, Pseudospondias longifolia, Chrysophyllum lacourtianum and Landolphia mannii. The lowest values have recorded with fruits of Antrocaryon klaineanum, Uapaca guineensis and Pentaclethra macrophylla has been also observed. Among plants analyzed for antibacterial activities, Tristemma mauritianum, Macaranga schweinfurthii, Medelina mirabilis, Alchornea floribunda and Pentaclethra eetveldeana present the

Proximate analysis
The moisture and ash content of samples of plants parts were determined using standard chemical methods as described by Association of Official Analytical Chemists (AOAC, 1990). For moisture, 2 g of sample was dried at 105°C for 24 hours. The ash content was determined by incineration of 2g of the sample in a muffle furnace at 550°C for 6 hours. Soxhlet extraction technique using petroleum ether (40-50°C) was used to evaluate the fat content of the sample (Pearson et al., 1981).
Bradford method was used to determine the crude protein content of the sample (Bradford, 1976). The carbohydrate content of the sample was determined by Dubois method (Dubois et al., 1956). The crude fiber content of the sample has been estimated from the formula (% carbohydrate= 100% -sum of percentage of moisture, ash, fat, crude fiber and crude protein contents) (

Mineral Analysis
The mineral contents of the samples were estimated by the wet digestion method (AOAC, 1995). Briefly, 1 g of the powdered plant sample was mixed with a10 mL of nitric acid, HNO3 (100%) in a Becher. The digestion was carried out at low heat until the brown fumes had been given off, and heating continued until all the solids dissolved and the appearance of white fumes. Then we added 3 mL of perchloric acid, HClO4 (70 %) and continued the digestion until the reduction of bulk. After cooling, the digest was filtered and transferred into 100 mL volumetric flask and made up to the mark with distilled water. The solution was used for the estimation of minerals. The K, Ca and Na were estimated by flame photometer (PFP76 Flame Photometer, Jenway), while Zn, Fe, Mg and Cu were determined using atomic absorption spectrophotometer (Model AA240FS, Varian). Phosphorus was determined by the Vanado Molybdate-Yellow method (AOAC, 2000).

Phytochemical analysis Preparation of plant extract
The plant parts consumed by the mandrillswere collected during the Behavioural data collection . Them samples collected were air-dried at room temperature for a total period six weeks and pulverized to powder using a clean electric blender (Model Phillips 190). A 25 g sample of the pulverized of each plant parts was lyophilized and the extract obtained is stored in vials protected from light until the completion of various tests. 120

Total Phenols content extracts
The Folin-Ciocalteu method was used to measure total amount of total phenols content (Singleton et al., 1999). Aliquots of 0.25 mL of each leaf extracts (1 mg/mL) were mixed with 1.25 mL Folin-Ciocalteu reagent (0.2 N diluted in methanol). A reagent blank using methanol instead of sample was prepared. After 5 min incubation at room temperature, 1 mL sodium carbonate solution (7.5%) was added. Samples were incubated at room temperature for 1 h and the absorbances were measured at 765 nm versus the prepared blank.
All tests were carried out in triplicate and total phenols content was expressed as mg of Gallic acid equivalents (GAE) per 100 g of drug.

Total flavonoids content extracts
The Dowd method was used to measure total amount of flavonoids (Arvouet-Grand et al., 1994) with slightly modification. Quercetin was used as standard. 1mL of 2 % AlCl3 in methanol was added to 1mL of plant extract (1 mg/mL). After 10 min of incubation at room temperature (20°C), absorbances were read at 415 nm. All tests were carried out in triplicate and results were expressed as Quercetin equivalent (QE).

Total tannins content extracts
The reference method of European Community was used to measure total amount of tannins (1994) with small modifications. Aliquots of 250 μl of extract (1 mg/mL) were added at 250 of μl ammonium citrate ferric reagent (3.5g/L) more 250 μl of ammonia (20%, 8g/L) and 1200 μl of H 2 O. After 10 min of incubation at room temperature (20°C), the absorbances were read at 525 nm. All tests were carried out in triplicate and results were expressed as Tannic acid equivalent (EAT).

Antioxidant activity index determination
The Antioxidant Activity Index (AAI) was determinate according to the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) method as described by Scherer and Godoy, (2009). Briefly, the working reagent was prepared by dissolving 10 mg of DPPH in 100 mL ethanol. Graded concentrations of extracts ranging from 0.781 to 100 μg/mL obtained by two-fold dilutions were prepared and 100 μL of each dilution were mixed with 100 μL of the extract solution. Absorbences were measured at 517 nm after 15 min incubation at room temperature in the dark. Ascorbic acid (Vitamin C) and Quercetin were used as references. The ability to scavenge DPPH radical was calculated by the following equation: RSA = [(Abs (control) -(Abs (sample)] / Abs (control)) x 100 With, RSA is the percentage of free radical scavenging activity. The IC 50 (concentration providing 50% inhibition) of extracts and standards was determinate using regression curves in the linear range of concentrations. The antioxidant activity index was calculated as following formula AAI= [DPPH (μg/mL)]/ IC 50 (μg/mL) Where [DPPH (μg/mL)], is the final concentration of DPPH.
[DPPH] is the final concentration of DPPH. We considered criteria of Scherer and Godoy according to which plant extracts show poor antioxidant activity when AAI < 0.5, moderate antioxidant activity when AAI between 0.5 and 1.0, strong antioxidant activity when AAI between 1.0 and 2.0, and very strong when AAI > 2.0.

Antimicrobial studies Test microorganisms
Microorganisms strains used in this study were principally multiresistant bacteria strains of mandrills from Bacteriology Laboratory of Centre International de Recherche Médicale de Franceville (CIRMF).These isolates were constituted byCitrobacter youngae (CY95, CY127), Escherichia coli (EC114, EC121, EC129 and EC292), Enterobacter cloacae complex (ECC110), Klebsiella pneumoniae ssp pneumonia (KPP32) and Pseudomonas aeruginosa (PA102 and PA383). These isolates were resistant at three standard antibiotics such as Cefotaxime, 121 Ceftazidime and Ertapenem. The selection of this these antibiotics depended on their availability and resistance to some antibiotics used in the treatment of human microbial infections. Thus microorganisms, well represented, are opportunists pathogens most frequently implicated in infectious diseases in tropical areas (Arvouet-Grant et al., 1994; Koudou et al., 2008).

Determination inhibition zone diameters
The assay was conducted as described by Bssaibis et al., (2009). Briefly, some bacteria strains from growth on Macconkey agar medium incubated at 37 °C for 24 h were suspended in saline solution 0.9% NaCl and adjusted to a turbidity of 0.5 McFarland standards(108 CFU/ml) (Lennette et al., 1981). Each suspension was used to inoculate into a Petri dish 90 mm diameter using a sterile swab (DeltaLab) .Then, 6 mm wells were dug into the agar of each Petri dish with a sterile cork borer. And 50 μL of each plant extract tested at 2000 μg / mL were put in these wells. The dissolution of the extract was added by 0.5% (v/v) DMSO which did not affect microorganism growth, according to our control experiments. Diffusion discs of Cefotaxime (CTX 30 μg), Ceftazidime (CAZ 10 μg), and Ertapenem (ERT 10 μg), (Bio-Rad) were used as positive reference standard to determine the sensitivity of the strains. Plates were incubated aerobically at 37°C for 24 h. The antimicrobial activities were evaluated by measuring the diameters of the inhibition zones with a graduated rule.

Determination the Minimum Inhibitory Concentration by Broth Dilution Assay
The microdilution method was used to determine minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of the extract against the test microorganisms as described by Bssaibis et al., (2009). The extracts dissolved in 0.5% DMSO were transferred in tubes to obtain a two-fold serial dilutions ranging from 4.8 to 2500 μg/mL. The tubes were inoculated in air with microbial suspensions at 37°C for 24 hours. MIC was recorded as a lowest extract concentration demonstrating no visible growth in the broth. MBC was recorded as a lowest extract concentration that kills 99.9 % of bacterial inoculate. MBC values were determined by removing 100 μl of bacterial suspension for subculture demonstrating no visible growth and by inoculating nutrient agar plates. Plates were incubated at 37°C for a total period of 48 h (Obame et al., 2007, Koudou et al., 2008.
The mean of moisture content was 35.18 ± 4.99% DM and the values were found between 3.6 ± 0.8 and 88.5 ± 0.7% DM. Mean of ash content was 5.92 ± 0.68% DM and the values were ranged between 2.7 ± 0.3 and 11.7 ± 0.9% DM.

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The crude fiber content of vegetables was found between 1.4 ± 2.1% and 41 ± 1.0% DM and their mean was of 10.55± 1.8% DM. All data were expressed as mean ± SD of triplicate experiment (n = 3). 123

Minerals composition of the wild vegetables consumed by mandrills.
The mineral compositions of 22 wild vegetables from mandrill diet such as potassium (K), calcium (Ca), sodium (Na), magnesium (Mg), phosphorus (P), iron (Fe), zinc (Zn), and copper (Cu) are presented in Table 2.
The results show that the high mineral content was obtained with the majority of the organ of plants eaten. Our results shown also that ratio Na/K of 22 plant species analyzed was ranged from 0.01 (Aframomum alboviolaceum and Macaranga schweinfurthii) to 2.36 (Palisota ambigua) and the ration Zn/Cu was from 0.75 (Aframomum cf polyanthum) to 6.79 (Aframomum daniellii) (

Antioxidant Activity Index (AAI)
The results of the antioxidant activity of some fruits and seeds extracts of food plants from mandrill diet and consumed by local population are presented in the table 5.

Inhibition zone diameters by disc assay of some food plants from mandrill diet used in traditional medicine by local population.
The inhibition zone diameters (IZD) obtained in the antimicrobial susceptibility assays for the plants extracts tested and standard antimicrobial drug discs are showed in Table 6.
The results showed that IZD recorded were ranged between 7 and 22 mm. The highest IZD was observed with the fruits of Eriosema glomerata (22 mm) and leaves of Piptadeniastrum africanum (20 mm). The lowest IZD have been obtained with seeds Xylopia staudtii (7 mm), leaves of Tristemma mauritianum (8 mm). These results showed also that some plant parts of some plants such as Medelina mirabilis, Pentaclethra eetveldeana and Eriosema glomerata have been active on the strains of Escherichia coli and Enterobacter cloacae complex resistant at standard antibiotic.    Discussion:- The nutritional value of a vegetable depends on its nutrient and anti-nutritional constituents (Aletor et al., 1994). The results of nutritional content analysis have shown that crude protein content was relatively higher in wild food plants from mandrill diet and used also by native population. It was highest in the seeds of Ricinodendron heudelotii, Pentaclethra macrophylla, and abundant in the fruits of Uapaca guineensis and Aframomum alboviolaceum. The protein content in those wild vegetables were comparable with or higher that crud protein content reported by some authors on exotic vegetables like lettuce, cabbage and spinach (Yildirim et al., 2001) commonly consumed in South Africa. 2. Our study shows also that crud protein content of twenty-two wild vegetables analyzed were ranged from 1. It has been also shown that the consumption of vegetables relatively high in crude fibers to reduce serum cholesterol level, risk of coronary heart diseases and hypertension. It also increases glucose tolerance and insulin sensitivity (Araya et al., 2003). That suggests that some wild edible vegetables from mandrill diet like Chrysophyllum africanum would be a good source of dietary fibers in human diet. 10. Lipids are essential nutrients since they provide the body with maximum energy. Our study reveals that crude lipids content in wild vegetables such as Aframomum daniellii, Landolphia mannii and Pentaclethra macrophylla were very higher than 18.4% DM, reported for the leaves of Adansonia digitata (Osman, 2004 (Udousoro and Ekanem, 2013). It has been reported that in healthy humans, the rate of gastric emptying is a function of caloric value (Calbet et al., 1997). On the whole, our results show that some wild edible vegetables from mandrill diet would be a good food source of energy and nutrient content usable in the human diet. 14. The content of ashes in leafy vegetables is a reflection of the amount of mineral elements present in the vegetables [Fagbohun et al., 2012]. 15. The content of ashes of the plant food would imply the mineral content, of where very nourishing, but it has been reported that it would be the reverse if the ash contained toxic metals [Ukam, 2008]. 16. Therefore, high ash content is not necessarily a conclusive factor regarding the health benefits of vegetables. 17. However, it is reported that with ash content greater than 8.8% DM are healthful [Ifon and Bassir, 1980]. 18. Thus, these food plants would be the good source of mineral content in the human diet. 19. The essential minerals (K, Na, Ca, P and Mg) and trace minerals (Fe, Cu and Zn) values of twenty-two wild food plants from mandrill diet show that the Na and K were the most abundant. Sodium and potassium are closely related in the body fluids. They regulate the acid-base balance. A diet high in potassium and low in sodium content has added advantage because of the direct relationship of sodium intake with hypertension in humans (Njoku and Akumefula, 2007). 20. According to Akinyeye et al. (2010), the recommended Na/K ratio is 0.6, and the values obtained with twentytwo vegetables analyzed was less than 0.6 except Palisota ambigua. 21. Thus, the wild food plants would be considered as good source of K and Na for effective health utilization.  (Brody, 1994;Ghani et al., 2012). Calcium is an essential structural and functional element in living cells. It participates in cell division and the regulation of cell proliferation and differentiation (Whitfield et al., 1979). The Ca is an important macronutrient for the growth and maintenance of teeth, bone, muscle and heart function (Akubugwo et al., 2007). It is with phosphorus content was also low (5.72 mg/100g). It is with phosphorus the minerals present in the largest quantity in the structure of the body and bones (Shills and Young, 1988). The phosphorus values found by wild vegetables were significantly comparable with the values reported in vegetables consumed in Western Côte d'Ivoire (Zoro et al., 2014). These data indicating that the wild vegetables from mandrill diet would provide a good source of minerals in human diets. 23. Our study reveals that the Fe values of some wild vegetables such as Aframomum cf polyanthum, Landolphia mannii and Medinilla mirabilis were very highest than the average values recommended in dietary intake which are of 400 g/day of fresh leafy vegetables that would result in an intake of about 40 g of dry vegetables per day [FAO, 2004]. The recommendation is an agreement with the results obtained in our study and proved that wild vegetables from mandrill diet would be a good source of Fe in human diet. Fe is important in the diet for the formation of hemoglobin, normal functioning of the central nervous system and in the metabolism of carbohydrates, proteins and fats (Kaya and Incekara, 2000;Gupta, 2014). It is also an important mineral in immune function, cognitive development, temperature regulation and energy metabolism (Wardlaw et al., 2004). 24. The Mg was relatively abundant in some plant like Aframomum alboviolaceum and Pentaclethra macrophylla.
It is required in over 300 enzymes that utilize adenosine triphosphate. It contributes to DNA and RNA synthesis during cell proliferation. It is necessary for nerve and heart function as release of insulin and ultimate insulin action on cell and decreases also blood pressure by dilating arteries (Wardlaw et al., 2004). 25. The results of mineral composition have also shown that the Zn and Cu values recorded in different vegetables were higher. These values were significantly higher than those reported for wild vegetables consumed in Bangladesh (Satter et al., 2016). The Zn is important mineral which is required in antioxidant system of organism. It is the component anti-oxidative enzymes, superoxide dismutase, catalase and glutathione peroxidase.

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26. Also, Zn is required for the function of 200 enzymes and is important in growth and sexual development in man (Kawade, 2012). 27. Copper is important in diet since it is a very powerful pro-oxidant and catalyzes the oxidation of unsaturated fats and oil as well as ascorbic acid (John, 1999). The copper content in all studied will vegetables were highest compared to recommended in human diets since the RDA value for copper is 1.5-3 mg for a male adult (NRC, 1989 Analyzing the activity reports (MBC/MIC) of plant extracts, the results show that is ranged between 2 and 64. It is demonstrated that if this activity report of extract is inferior at 4 (≤4), it is considerate as presenting a bactericide activity and if it is superior at 4 (≥ 4), the extract is considerate as bacteriostatic (Marmonier, 1990 eetveldeana will be the bactericide effect. 40. Thus, this study has permeated of showed that the mandrill will use their vegetable resources of their ecosystem for to respond at their need in energy, mineral and probably for their needs of heart. 41. In additional, the highest phenol compounds values in the plant parts from mandrill diet will permitted also of supposed that the use of important diversity of vegetables by this primate species (Hoshino, 1985;Lahm, 1986;Norris, 1988; Nsi Akoué et al., 2017; Nsi Akoué, 2017) will be justified by their needs in secondary metabolites for to prevent or control the microbial affections.

Conclusion:-
In the present study, analytical investigations were carried out to ascertain the chemical composition, nutritional proximate, antioxidant and antibacterial potentials of wild vegetables from mandrill diet.
The results showed that plant species consumed by this non-human primate species present an important of good nutritional sources of nutrients and mineral compounds. Also, that some plants will be of good natural antioxidants sources usable by local population. Among all plants analyzed, T. mauritianum, M. schweinfurthii, M. mirabilis, A. floribunda and P. eetveldeana present the bactericide effects and certain among other have bacteriostatic effects on gastrointestinal bacteria. Higher phenolic contents and others secondary metabolites in the alimentation of Mandrillus sphinx supposed that some food plants will be selected for their secondary metabolite contents and will explicate also the bactericide activity observed. These pharmacological results attested the bioefficacy of certain food plants consumed by this primate species.
Thus, insertion of certain of these vegetables in human nutrition is recommendable. These interesting primarily results will be completed by other analysis for a good knowledge of nutritional behavior of this primate species.