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L’utilisation abusive des produits chimiques de synthèse pose un problème de santé publique. Afin de contribuer à la protection écologique durables des cultures, les effets aphicides in vitro de l’huile essentielle de Ocimum basilicum L. une plante de la flore togolaise et son composé majoritaire, l’estragole, ont été évalués sur les adultes du puceron Aphis gossypii. Les tests biologiques ont été effectués en laboratoire selon la méthode recommandée par Insecticide Resistance Action Commitee (IRAC) N° 1 Version 2. Les résultats obtenus ont révélé que l’huile essentielle de O. basilicum et l’estragole ont montré une activité insecticide intéressante sur les pucerons. La concentration minimale pour obtenir 100% de mortalité a été de 3 μL.mL-1 pour l’huile essentielle et de 2 μL.mL-1 pour l’estragole. Les DL50 obtenues sont de 1400 ppm pour l’huile essentielle et de 700 ppm pour l’estragole. L’huile essentielle et son composé majoritaire se sont révélés efficaces in vitro avec un effet de toxicité plus élevée de l’estragole sur A. gossypii. Les tests en milieu réel et l’évaluation de leur innocuité sur les organismes non cibles seront nécessaires pour confirmer l’intérêt de ces résultats dans l’élaboration d’une stratégie de gestion intégrée à l’aide de ces pesticides naturels contre ce ravageur redoutable. © 2020 International Formulae Group. All rights reserved. Mots clés: Cotonnier, Aphis gossypii, Ocimum basilicum, huile essentielle, estragole English Title: Aphicide effect of the essential oil of Ocimum basilum L. and its majority compound on cotton aphid Aphis gossypii Glover (Homoptera: Aphididae) in Togo English Abstract The excessive use of synthetic chemicals is a public health issue. In order to contribute to sustainable ecological crop protection, in vitro aphicide effects of the essential oil of Ocimum basilicum L. a plant of Togolese flora and its majority compound, estragole, were evaluated on the adults of the aphid Aphis gossypii. Laboratory biological tests were conducted using the method recommended by the Insecticide Resistance Action Committee (IRAC) 1 Version 2. Results showed that essential oil of O. basilicum and estragole had interesting insecticidal activity on aphids. The minimum concentration to achieve 100% mortality was 3 μL.mL-1 for the essential oil and 2 μL.mL-1 for the estragole. Lethal Dose (LD50) values were 1400 ppm for the essential oil and 700 ppm for the estragole. The essential oil and its majority compound were effective in vitro with a higher toxicity effect of estragole on A. gossypii. Field tests and the evaluation of their safety on non-target organisms will be necessary to confirm the relevance of these results for an integrated management strategy development, using natural pesticides against this devastating pest. © 2020 International Formulae Group. All rights reserved. Keywords: cotton plant, Aphis gossypii, Ocimum basilicum, essential oil, estragole

The buds essential oil of Syzygium aromaticum (Myrtaceae) from Togo were steam-distilled and investigated for percentage composition and antimicrobial activity. Eugenol (82.95 %), eugenyl acetate (5.01 %), β-caryophyllene (3.14 %) were the major components of the analysed sample. The in vitro microbiological experiments revealed that on tested bacteria, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) ranged from 30 to 50 μl/L and from 60 to 120 μl/L respectively. This makes S. aromaticum suitable for use as a source of active ingredients in the formulation of natural toothpaste and lotions for mouth washes.

Leaf essential oil of Coleus aromaticus (Lamiaceae) from Cambodia was steam-distilled and investigated for its percentage composition and antibacterial activity against ffteen oral microflora pathogen strains. The volatile oil sample investigated in this work contained mainly thymol (57.4%), carvacrol (13.5%), γ-terpinene (5.6%), and p-cymene (5.2%). The in vitro antibacterial experiments revealed that on tested bacteria the minimum inhibitory concentration (MIC) ranged 40–80 µL/Land the minimum bactericidal concentration (MBC) 80–150 µL/L. These findings support the idea that the C. aromaticus essential oil sample tested here could be suitable for use as a natural active ingredient in natural and low-cost drugs against oral microflora.

The leaf essential oil of Chromolaena odorata L. (Asteraceae) harvested in Togo were steam-distilled and investigated for chemical composition (GC and GC-MS) and in vitro potential cytotoxic activity on human epidermic cell line HaCat. The chemical composition showed that the main constituents of essential oil sample were respectively β-caryophyllene (25.2 %), germacrene D (18.8 %), and linalool (7.9 %). The in vitro cytotoxicity bioassays on human cell line HaCaT did not revealed any toxicity of C. odorata essential oil up to 3000 μL.mL−1. Pure commercial β-caryophyllene and germacrene D standards appeared almost non-toxic (IC50 >3000 μL.mL−1), proving the major role played by the major components in the overall cell viability showed by the C. odorata oil sample tested in this work.

Avec la diminution progressive des surfaces pâturables liee a une multitude de facteurs dont le surpâturage, les aleas climatiques doubles des diverses activites anthropiques, l’elevage des ruminants se tourne de plus en plus vers la production fourragere afin d’assurer aux animaux une alimentation convenable et continue. Le but de cette etude est d’etablir un etat des lieux des pratiques de production et d’exploitation de fourrage effectuees par les eleveurs au Togo. A cet effet, 133 unites d’elevage de ruminants regulierement suivies par l’Institut de Conseil et d’Appui Technique (ICAT), ont ete enquetees puis suivies pendant deux ans. Des resultats obtenus, il ressort que les especes Gliricidia sepium, Panicum maximum et Leucaena leucocephala sont les fourrages les plus utilises dans des proportions respectives de 92, 78 et 51%. Aussi, l’utilisation des especes fourrageres dans l’installation des clotures de maisons et d’habitats pour animaux, l’installation definitive de parcelle fourragere ainsi que l’insertion de la production fourragere dans la rotation culturale sont trois modes de production fourragere identifies aux taux respectifs de 48, 31 et 15%. Par ailleurs, l’affouragement au parc et la conduite sur parcelle fourragere sont essentiellement les deux methodes d’exploitation des fourrages produits dans des proportions respectives de 62 et 37%. Mots cles : fourrage, exploitation, Panicum maximum, Gliricidia sepium, Leucaena leucocephala.

The aerial parts of Ocimum gratissimum L. (Lamiaceae) harvested in Togo was steam-distilled and investigated for essential oil composition (GC and GC/MS) and in vitro antifungal activities. Thymol (31.79 %), p-cymene (15.57 %) and I³ -terpinene (12.34 %) and were the major components of the oil. Other notable components identified in this oil were myrcene (6.94 %) and I± -thujene (6.11 %). The in vitro antifungal activity was recorded with the minimum inhibitory concentrations (MICs) ranging from 80 to 150 µl. l -1 , 150 to 500 µl.l -1  and from 100 to 150 µl.l -1 respectively on dermatophytes, imperfect filamentous fungi and pathogenic yeasts. Likewise, o n tested fungi the minimum fungicidal concentration (MFC) varied from 300 µl.l -1 to 500 µl.l -1 , 500 to 700 µl.l -1 and from 250 to 300 µl.l -1 , respectively on dermatophytes, imperfect filamentous fungi and pathogenic yeasts . Keywords : O.gratissimum ,  Antifungal, Essential oil; Thymol.  © 2009 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.  DOI: 10.3329/jsr.v1i1.1131 Â

Essential oil extracted (4.4% in yield) from air-dried fruits of Xylopia aethiopica harvested in Togo was investigated for percentage composition and in vitro cytotoxicity. The chemical composition of the essential oil was examined by GC and GC/MS. Thirty-five compounds were identified representing 89.9% of total oil. The major constituents were β-pinene (23.6%), α-pinene (11%), sabinene (9.8%), germacrene D (8.3%) and 1,8 cineole (8.2%). The cytotoxicity of the volatile oil was evaluated in vitro on the human epidermal cell line HaCaT. The tested sample did not show any cytotoxicity (IC50 >3000 μg.ml-1) effect at concentrations around 3000 μg.ml-1. Further testing in bioassay would probably help in validating some of medicinal uses of X. aethiopica in topical drugs and/or in cosmetics as natural products.

Morphogenetic capacities of Ocimum gratissimum were revealed in vitro from nodal segment—derived shoots cultivated with α-naphtalene acetic acid (NAA, 0.54 or 5.37 μM), or indolebutyric acid (IBA, 2.45 μM), or 6-benzylamino- purine (BAP, 0.44 or 4.44 μM) or kinetin (Kin, 0.46 or 4.65 μM). NAA or IBA decreased caulogenesis and slowed down rooting. Both auxins improve growth of the shoots by elongation of the inter-nodes. BAP (4.44 μM) or Kin (4.65 μM) led to bushing shoots. Four months old plantlets (10%) were successfully acclimatized in greenhouse, before being cultured in field. Essential oils were analyzed by simple gas chromatography and coupled with the mass spectrometry. Essential oil efficiencies (EO %) were found to be superior to these of the mother plant and thymol, p-cymene, γ-terpinene and s-myrcene could be mainly identified in the harvested plants.

Bugs (Heteroptera), secondary devastators in comparison to caterpillars before 1980, constitute nowadays an important entomologic factor in the shedding of buds and new bolls. An evaluation of their damage and that of the caterpillars on shed organs was realized in an apparatus corresponding to a three method of protection. Statistical analyses (ANOVA) of results have shown in the first mode (NT) that the average of bugs’ damage on buds (49.25 ± 3.94) and new bolls (101.5 ± 6.65) is significantly higher than that of caterpillars (36.75 ± 3.25) and (51.75 ± 7.43) respectively. Treatments realized in the second mode (ST) allowed the reduction of the average of bugs’ damage by 31.50 ± 5.12 on buds and by 61.25 ± 2.75 on new bolls and that of caterpillars by 24.25 ± 2.62 and by 29.00 ± 4.43 respectively on buds and on bolls. The treatment of the third mode (PP) also led to a reduction of bugs’ damage by 24.25 ± 2.65 on buds and by 56.25 ± 7.20 on new bolls and respectively 16.25 ± 1.93 and 29.75 ± 3.06 the damage of caterpillars.

Essential oils of Aeollanthus pubescens Benth. and Ocimum gratissimum L. (Lamiaceae) from Togo were investigated for their percentage composition and in vitro cytotoxicity. The GC and GC-MS analyses indicated that the major constituents of both essential oils were thymol, p-cymene and γ-terpinene. Testing of these volatile oils and their major constituents from commercial origin in vitro for possible cytotoxicity on the human epidermic cell line HaCat showed that the toxicity of the essential oil of A. pubescens (IC50: 1800µg.ml−1) was higher than that of the essential oil of O. gratissimum (IC50: 2400 µg.ml−1). Pure commercial thymol standard showed a cytotoxicity (IC50: 1800 µg.ml−1) identical to that of the A. pubescens essential oil. Conversely, p-cymene and γ-terpinene standards were found almost non-toxic (IC50 >3000 µg.ml−1). These findings support the assumption that the cytotoxic activities of the tested essential oils were basically due to their high level content in thymol.

Five essential oils of African Lamiaceae (Aeolanthus pubescens Bent., Ocimum canum Sims., O. gratissimum L., O. sanctum L., Platostoma atricanum P.B.) have been investigated chemically by means of GC-MS. Chemotypes have been clearly defined. Antibacterial and antifungal tests in vitro have been undertaken upon strains of humans and pets cutaneous microfloras. In culture, these oils don't destroy the saprophytes. On the contrary, Aeolanthus pubescens, Ocimum gratissimum (thymol chemotypes) and Platostoma atricanum (methyl-eugenol and eugenol chemotype) inhibit the development of many pathogenic fungi.

The steam-distilled leaf and flower oils of Ocimum basilicum L., Ocimum canum Sims and Ocimum gratissimum L., collected from 14 different locations in Togo, have been studied. Capillary gas–liquid chromatography and capillary gas-chromatography coupled with mass spectrometry were used to determine the percentage composition of these essential oils. The oils from O. basilicum mainly contained either estragole or a linalol–estragole mixture. In those from Ocimum canum, terpin-4-ol, linalol, υ-terpinene and the sesquiterpene hydrocarbons (β-caryophyllene, (E)-α-bergamotene and bicyclogermacrene) were the major compounds. Thymol, υ-terpinene and p-cymene were identified as the most abundant constituents in the Ocimum gratissimum oils. © 1998 John Wiley & Sons, Ltd.

The aerial parts essential oils of Ocimum basilicum (Lamiaceae) from Togo were steam-distilled and investigated for their percentage composition (GC and GC/MS) and in vitro antimicrobial activities. Five oil chemotypes were identified and classified as follows in line with their principal components: estragole type; linalool/estragole type; methyleugenol type; methyleugenol/t-anethole type; t-anethole type. The in vitro microbiological experiments revealed that only the methyleugenol and methyleugenol/t-anethole chemotypes were active against tested fungi and bacteria. Their minimum inhibitory concentrations (MIC) ranged from 80 to 150 µL/L and from 200 to 500 µL/L respectively. Likewise, o n tested bacteria the MIC varied from 200 µL/L to 400 µL/L and from 250 to 500 µL/L respectively. These findings are supportive of the potential of both basil oil chemotypes for use as active ingredients in natural antibiotic drugs.

The leaf essential oils of Cymbopogon citratus L. and Cymbopogon nardus L. (Poaceae) from Togo were steam-distilled, analyzed for percentage composition and investigated in vitro for their potential cytotoxic activity on human epidermic cell line HaCat. The percentage composition showed that the main constituents of essential oils samples were respectively geranial (45.2%), neral (32.4%) and myrc¨ne (10.2%) for C. citratus essential oil and citronellal (35.5%), geraniol (27.9%) and citronellol (10.7%) for that of C. nardus . The in vitro cytotoxicity bioassays on human epidermic cell line HaCaT revealed that the toxicity of the essential oil from C. citratus (IC 50 : 150 µL.mL -1 ) was higher than that of the essential oil from C. nardus (IC 50 : 450 µL.mL -1 ). Pure commercial neral, geranial, and citronellal standards showed respectively the following IC 50 values: 100, 250 and 300 µL.mL -1 ). Conversely, pure citronellol standard appeared almost non-toxic (IC 50 >1000 µL.mL -1 ), proving the major role played in synergy by neral and geranial in the overall toxicity showed by the citratus oil sample tested in this work.

The leaf and stem steam-distilled oil of Aeollanthus pubescens Benth. cultivated in Lome (Togo) was isolated and analyzed for percentage composition using both GC and GC/MS. Oils from fresh or dry herb contained thymol (46–50%) and γ-terpinene (12–13%) as the main components.

The leaf essential oil of Chromolaena odorata L. (Chenopodiaceae) from Togo were steam-distilled, analyzed by GC and GC-MS for chemical composition and investigated in vitro for its potential cytotoxic activity on human epidermic cell line HaCat. The chemical composition showed that the main constituents of essential oil sample were respectively ascaridole (51.12 %), p-cymene (19.88 %), neral (8.70%) and geraniol (7.55%). The in vitro cytotoxicity bioassays on human cell line HaCaT revealed moderate toxicity level of C. ambrosioides essential oil IC 50 with 700 μL.mL -1 . Pure commercial neral standard showed high toxicity with IC 50 value of 100 μL.mL -1 ). Conversely, pure ascaridole p-cymene and geraniol standards appeared almost non-toxic (IC 50 >1000 μL.mL -1 ), proving the major role played by neral in the overall toxicity showed by the C. ambrosiodes oil sample tested in this work. Keywords: Chenopodium ambrosioides ; Essential oil; Ascaridole; p-cymene; HaCaT cell line; Cytotoxicity. DOI: 10.3329/bjsir.v44i4.4594 Bangladesh J. Sci. Ind. Res. 44(4) , 435-440, 2009

The stem bark of Grewia venusta and the flower sepal of Bombax costatum , two mucilaginous plants, were investigated as potential sources of bioadhesives for formaldehyde-free particleboards. Mucilage and pectin fractions of both plant organs were analysed for monosaccharides identification and quantification. The binding properties of these mucilages were investigated by testing mechanically particleboard made with the extracted mucilages. The aqueous extraction and ethanolic precipitation, followed by ionic chromatography gave the following results. Depending on the plant organ, extraction yield varied from 12% to 45 %. The pectin from B. costatum contained mainly rhamnose and arabinose (85%), while G. venusta bark's pectin enclosed basically arabinose, glucose and fucose (80%). The mechanical behaviour of the panels met most of the requirements of ANSI 208.1 standard. Keywords: Bombax costatum, Grewia venusta , Pectin, Mucilage and Monosaccharides DOI: 10.3329/bjsir.v44i2.3681 Bangladesh J. Sci. Ind. Res. 44(2), 247-253, 2009