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Today the use of plant extracts, in particular essential oils, is a natural alternative to synthetic insecticides in the fight against crop pests. The purpose of this research is to determine the chemical composition of the ylang-ylang Cananga odorata (Lam.) Hook. F. & Thomson leave essential oil and to evaluate on the one hand its ovicidal, larvicidal, insecticidal, anti-oviposition and insect repellent properties, and on the other hand its effectiveness in preserving the weight of the grains and the germination power of rice seeds against the Angoumois grain moth Sitotroga cerealella O., a major pest of rice in Benin. The essential oil from the leaves of the C. odorata (Lam.) Hook. F. & Thomson was obtained by hydro-distillation, and analysed by gas chromatography-mass spectrometry (GC-MS). The analysis showed that the oil contains 32 main compounds, the major ones being α-pinene (7.01%), lavandulyl acetate (7.19%), caryophyllene (30.33%), α-humulene (13.42%) and germacrene D (8.99%). Based on the findings of fumigation bioassays, the Cananga odorata (Lam.) Hook. F. & Thomson essential oil showed high toxicity against adult of the S. cerealella with values CL50 of 0.094μl/mL and CL90 of 0.46μl/mL. Similarly, our work has demonstrated that this oil has ovicidal and larvicidal or egg development retardant properties. It also caused strong oviposition inhibition activity of more than 97% in female of the S. cerealella O. and subsequently developed very good repellent or deterrent properties, with an average repellence rate of 75.7% against the S. cerealella O. insect. These insecticidal effects preserved grain weight, with weight losses of at most 0.38% and a paddy rice seed germination rate of more than 80% at the lowest applied dose of 0.2µL/mL.The essential oil from the leaves of the C. odorata (Lam.) Hook. F. & Thomson can be used as an alternative to modern toxic synthetic chemicals, for protection against this important pest of grains in storage in Benin.

Gum arabica is a local commercial nutraceutical and food preservative collected mostly from acacia plants. HPLC-DAD analysis identified gallic acid, syringic acid, ferulic acid, coumarin, rutin and rosmarinic acid in hydroethanol extracts of all three acacia species with ferulic acid being the most abundant component in Acacia ataxacantha (45.25 ± 0.33 mg/g) Acacia sieberiana (130.3 ± 0.65 mg/g) and Acacia nilotica (125.50 ± 0.51 mg/g). Extracts displayed good antioxidant capacities in β-carotene-linoleic acid, DPPH•, ABTS•+, CUPRAC and metal chelating assays and extracts were more active than the standards used in the DPPH•, ABTS•+ and CUPRAC assays. Extracts inhibited violacein production in Chromobacterium violaceum CV12472 at MIC and sub-MIC concentrations as well as quorum sensing in C. violaceum CV026 under externally supplied acylhomoserine lactone. The extracts showed antimicrobial activity with MIC values ranging from 0.1562 mg/mL to 2.5 mg/mL on Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Salmonella Typhi, Escherichia coli and Candida albicans with excellent biofilm inhibition at MIC and sub-MIC concentrations especially against E. coli. Extracts showed inhibitions on some enzymes with A. Sieberiana and A. Nilotica having very good anticholinesterase, antidiabetic (α-glucosidase and α-amylase) and antiurease activities. The results indicate the relevance of acacia in food applications

In the last decades, it has been intensively studied natural alternatives to synthetic products.Chassalia kollyis one of the medicinal plants used traditionally for treatment of skin infections. This study aimed at identifying the diversity secondary metabolites, to investigate the antioxidant and anti-inflammatory activities of ethanolic extract ofChassalia kollyleaves. Total phenols were determined by Folin Ciocalteu method. The aluminum trichloride method has been used to quantify total flavonoids, while the determination of condensed tannins was carried out by the hydrochloric vanillin method. The antioxidant capacity was evaluated by 2, 2-diphenyl-l-picrylhydrazyl (DPPH), 2, 2'-Azino-bis- (3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) and phosphomolybdenum methods.In vitroanti-inflammatory activity of ethanolic extract ofChassalia kollyleaves was evaluated by method membrane stabilization. In this results,Chassalia kolly leavescontain flavonoid, mucilages, anthocyans, sterols and terpenes, saponosides, alkaloids and reducing compounds. The contents of total phenols, total flavonoids and total tannins are respectively (20.41±2.11) µgGAE/mgDM; (30.29±2.18) µgQE/mgDM and (1.211±0.122)µgCE/mgDM. The results obtained during this work allowed us to assert that all extracts of the studied plant have very good antioxidant properties (IC50=0.05µg/µL). The ethanolic extract of the leaves ofChassalia kollyshowed an anti-inflammatory activity more interesting than aspirin which is the reference compound used in this study.

Infections due to Escherichia coli and Salmonella are of the major constraints for the laying hen’s industry as they cause mortality and serious economic losses. The use of conventional antibiotics to control bacterial has shown limits because it allows multidrug-resistance. The main objective of this study was to assess the antibacterial activity of essential oil from Aeollanthus pubescens on multidrug resistant strains of Salmonella and Escherichia coli isolated from laying hens faming in the department of Atlantique in Benin. Altogether, 11 strains of Salmonella and 16 strains of Escherichia coli have been isolated from 101 samples of different organs including liver, spleen, lung, feces and yolk according to standardized methods and their biochemical profile using API 20E gallery. Test of sensitivity was carried out on 11 antibiotics of six different families on identified strains in order to determine their resistance profile. A sensitivity test was carried out on multi-drug resistant strains with Aeollanthus pubescens essential oil to determine their sensitivity with regard to this essential oil. The results showed that the majority of Salmonella strains presented resistance to Tetracyclines (72.7%) and Sulfonamides (63.6%) and all Escherichia coli strains are resistant to Sulfonamides (100%) followed by Tetracycline (93.75%) and Ampicillin (75%). Aeollanthus pubescens essential oil was active on all the multi-drug resistant strains investigated with Minimal inhibitory concentration varying from 0.41 ± 0 mg/ml to 0.83 ± 0 mg/ml for Salmonella and from 0.41 ± 0 mg/ml to 1.66 ± 0 mg/ml for Escherichia coli (P Salmonella and the multi-drug resistant Escherichia coli investigated. Those results provide alternatives to control poultry bacterial pathologies in Republic of Benin. However, disease due to Escherichia coli and Salmonella must be taken more seriously and study on their resistance to antibiotic must be deepened as well.

Objectif: La présente étude vise à valoriser la pomme cajou, à travers l’étude de la cinétique de conversion de son jus en bioéthanol par voie fermentaire.Méthodologie et Résultats: Au cours de l’étude, les performances fermentaires des levures Saccharomyces carlsbergensis et de trois souches levuriennes de Saccharomyces cerevisiae, notamment Angel brand super alcohol, Angel super alcohol et Angel brand Thermal-tolerant alcohol dans la production de bioéthanol à partir du jus de pomme cajou ont été testées. Le suivi des paramètres cinétiques de fermentation du jus tels que le Brix, le pH, l’acidité et la densité, a montré une grande variabilité de ces paramètres au cours du processus de fermentation en présence et en absence de l’urée (CON2H4), utilisée comme facteur de croissance. La distillation des moûts en fin de fermentation a permis d’obtenir des taux d’extraction en éthanol (% v/v à 20°C) compris entre (20,48±0,02)% et (51,55±0,01)%. La meilleure performance de bioconversion éthanolique a été enregistrée avec Saccharomyces carlsbergensis et la souche Angel brand thermal-tolerant alcohol, en présence d’urée.Conclusion: Cette étude a montré que ces deux souches peuvent être utilisées comme des ferments efficaces, dans la perspective d’une production intensive de bioéthanol à partir du jus de pomme cajou.Mots-clés: pomme cajou, fermentation, levures, biocarburant, BéninEnglish Title: Evaluation of the fermentative potential of Saccharomyces cerevisiae and S. carlsbergensis in the production of bioethanol using cashew apple juiceEnglish AbstractObjective: The present study aims to valorize the cashew apple, through the study of the kinetic conversion of its juice for bioethanol production by fermentation process.Methodology and Results: During the study, the yeast fermentation performances of Saccharomyces carlsbergensis and three strains of Saccharomyces cerevisiae, including Angel brand super alcohol, Angel super alcohol and Angel brand Thermal-tolerant alcohol were tested. Monitoring fermentation kinetic parameters such as Brix, pH, acidity and density, showed a great variability of these parameters during the fermentation process in the presence and absence of urea (CON2H4), used as growth factor. Distillation of fermented liquids has yielded ethanol extraction rate (% v/v at 20°C) between (20.48±0.02)% and (51.55±0,01)%. The best ethanolic bioconversion performance was recorded with Saccharomyces carlsbergensis and the strain of Angel brand thermal-tolerant alcohol in the presence of urea.Conclusion: This study showed that both two strains could be used as effective ferments, in the perspective of intensive production of bioethanol using cashew apple juice.Keywords: cashew apple fermentation, yeasts, biofuel, Benin

The chemical composition of the essential oils obtained by hydrodistillation from leaves of three samples of Chenopodium ambrosioides L. (Chenopodiaceae) growing in Benin were analyzed by GC and GC/MS. To date the biological functions of Chenopodium ambrosioides L. essential oils have not been demonstrated scientifically. We investigated the chemical composition of Chenopodium ambrosioides L. essential oils and their antiradical antimicrobial and anti-inflammatory activities. Twenty three compounds were identified and quantified in the oils. The essential oils are rich in hydrocarbons monoterpenic. The major compounds being ?-terpinene (48.8%, 60.0%, 63.7%), ascaridole (19.7%, 13.8%, 11.7%), p-cymene (19.1%, 15.4%, 19.0%) and isoascaridole (2.5%, 1.6%, 0.7%). The antiradical and anti-inflammatory.

To avoid environmental pollution and health problems caused by traditional wood preservatives or synthetic pesticides which are becoming more restricted to use, there is an increasing search of naturally occurring toxicants from plants. Extractives of phytobiomass having termiticidal activity can be used as low hazard termite control agents. Meliaceae species are well represented in Africa and cover a size range from magnificent forest trees to small shrubs. They have a wide range of uses in ethno medicine, prompting further investigations for biological activity due to the variety of isolated compounds. In the present article the termiticidal activities of Azadirachta indica and Carapa procera (Meliaceae) seeds oils (AISO and CPSO) are screening by no-choice test and standard test EN 118 (2005). Only AISO shows a promising termiticidal activity and both oils have shown a promising repellent activity. AISO and CPSO have the same preventive activity by standard test EN 118 (3: moderate attacks). Additional work will be undertaken to check whether some seeds extracts (non timber products from sustainable management of native forest) could show even higher termiticidal activity under more adverse conditions (polar solvents, cold temperature extraction under pressure) and could be alternative active natural products to synthetic compounds.