Cymbopogon Schoenanthus Research Articles

Chemical composition and antifungal activity of Cymbopogon schoenanthus harvested in Béchar region, Algeria

Cymbopogon schoenanthus is a natural plant that often grows in tropical regions such as North and West Africa. In order to valorize this aromatic plant from southern Algeria, we were interested in the chemical characterization of its essential oil by GC(Ir), GC-MS, and 13C NMR, and in the determination of the antifungal activity of its essential oil against toxinogenic strains isolated from spices sold in bulk. The detailed chemical analysis of all the parts of the plant collected from the station of El aguid of Bechar allowed to identify 48 components The composition was dominated by various alkohols bearing thep-menthane skeleton : cis-p-menth-2-en-1-ol (22.3%), trans-p-menth-2-en-1-ol (10.2%), cis-piperitol (10.1%) and trans-piperitol (5.3%). Monoterpenes hydrocarbons were representedby δ-2-carene (16.0%) and limonene (4.7%).β-elemol (4.8%) was the main oxygenated sesquiterpene followed by juniper camphor(2.6%), β-eudesmol (1.9%), selina-6-en-4α-ol(1.9%), intermedeol (1.4%) and α-eudesmol(1.3%). However in the second part of our study the essential oil of C. schoenanthus showed good activity towards Aspergillus fumigatus and AspergIllus flavus with inhibition zone diameters of 29.5mm and 23mm while the activity was lower towards Penicillium sp with a diameter of 11mm. The result of activity towards the toxic strain Penicillium sp has never been reported in the literature. On the other hand, the chemical characterization of the essential oil of the plant is the first one made on the station of el aguid of Bechar.

Camel Grass Phenolic Compounds: Targeting Inflammation and Neurologically Related Conditions.

The use of plants for therapeutic purposes has been supported by growing scientific evidence. This work consisted of (i) characterizing the phenolic compounds present in both aqueous and hydroethanol (1:1, v/v) extracts of camel grass, by hyphenated liquid chromatographic techniques, (ii) evaluating their anti-inflammatory, antioxidant, and neuromodulation potential, through in vitro cell and cell-free models, and (iii) establishing a relationship between the chemical profiles of the extracts and their biological activities. Several caffeic acid and flavonoid derivatives were determined in both extracts. The extracts displayed scavenging capacity against the physiologically relevant nitric oxide (•NO) and superoxide anion (O2•-) radicals, significantly reduced NO production in lipopolysaccharide (LPS)-stimulated macrophages (RAW 264.7), and inhibited the activity of hyaluronidase (HAase), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Some of these bioactivities were found to be related with the chemical profile of the extracts, namely with 3-caffeoylquinic, 4-caffeoylquinic, chlorogenic, and p-coumaric acids, as well as with luteolin and apigenin derivatives. This study reports, for the first time, the potential medicinal properties of aqueous and hydroethanol extracts of camel grass in the RAW 264.7 cell model of inflammation, and in neurologically related conditions.

Chemical Analysis of Essential Oils of Cymbopogon schoenanthus (L.) Spreng. and Nepeta azurea R.Br. ex Benth from Djbouti, In-Vitro Cytotoxicity against Cancer Cell Lines and Antibacterial Activities

The aim of this research was to evaluate the essential oils of two medicinal plants from Djibouti: Cymbopogon schoenanthus (L.) Spreng. and Nepeta azurea R.Br. ex Benth. in cytotoxic activity against thirteen (13) cancer cell lines (A2780, A549, HCT116, HEK-293, JIMT-T1, K562, MIA-Paca2, MRC5, NCI-N87, PC3, RT4, U2OS and U87-MG) and antibacterial activity against seven (7) Gram (−) strains (Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella enterica sv. Typhimurium and Shigella sonnei) and five (5) Gram (+) strains (Corynebacterium sp., Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus agalactiae). The plants were extracted by hydrodistillation and were analyzed by GC-MS. The main components of Cymbopogon schoenanthus essential oil (CSEO) were 3-isopropenyl-5-methyl-1-cyclohexene (32.3%) and D-Limonene (11.3%), and the main component of Nepeta azurea essential oil (NAEO) was methyl (2E)-2-nonenoate (53.2%). The two essential oils showed inhibitory cytotoxicity activities of all the cancer cells tested; on the other hand, the antibacterial activities are only well-noticed for the CSEO oil at a concentration of 5% against Klebsiella pneumoniae, Pseudomonas aeruginosa, Corynebacterium sp., Enterococcus faecalis and Staphylococcus aureus. Our results demonstrated that the two essential oils could be effective natural anticancer agents, in addition to an antibacterial character for Cymbopogon schoenanthus essential oil.

Antifungal and antimycotoxic activities of 3 essential oils against 3 mycotoxinogenic fungi.

Fungal toxins can have various adverse health effects, including carcinogenic, teratogenic or hepatotoxic impacts. In addition, fungal alteration has also a negative impact on agricultural plant production. The use of chemical fungicides to control mycotoxin contamination is increasingly controversial and regulated. More environmentally friendly methods are therefore being explored. Essential oils, as compounds extracted from plants, are liquids whose specific aromatic compounds give each essential oil its own unique characteristics. Due to their rich chemical composition, essential oils (EOs) have many interesting properties, including antifungal activities. The objective of the present study was to analyze volatile chemical composition of EOs (Cymbopogon schoenanthus, Cymbopogon nardus and Eucalyptus camaldulensis) by GC/MS and to investigate their effects on the growth, sporulation and mycotoxin production of Aspergillus flavus, Aspergillus carbonarius and Fusarium verticillioides (aflatoxin B1, ochratoxin A and fumonisin B1, respectively). In addition, EOs influence on aflatoxin B1 (AFB1) and fumonisin B1 (FB1) biosynthesis pathways was explored using real-time qRT-PCR. The results obtained in vitro, by direct contact with the EOs and by diffusion of their volatile compounds, showed that the essential oils had inhibitory effects on the growth and the production of mycotoxins of the 3 fungal strains and modified the expression of some toxin synthesis genes. We conclude that the recorded effects were dependent on the combined effects of the EOs type, the fungal strains and the doses studied.

Essential oils and their binary combinations have synergistic and antagonistic insecticidal properties against Anopheles gambiae s. l. (Diptera: Culicidae)

Botanical biopesticides have potential for use in mosquito control because they exhibit low mammalian toxicity, are readily biodegraded, show target specificity and insecticidal activity. As populations of mosquito species grow more resistant to currently used organic insecticides, a need for new and effective insecticides for vector control becomes more urgent. This study reports the effects of synergistic and antagonistic essential oils (EOs) from Cymbopogon schoenanthus, Lantana camara, Lippia chevalieri and Lippia multiflora and their binary combinations against Anopheles gambiae s. l. larvae and adults. EOs insecticidal properties were tested with third to fourth-instar larvae and, non-blood-fed 3–5-day old field-collected An. gambiae using WHO and CDC bottle bioassays, respectively. Many compounds were found in the EOs mixtures. All EOs showed larvicidal and adulticidal activities with mortality from 0 to 100% against An. gambiae which were concentration dependent and EOs specific. EO mixture from C. schoenanthus and L. multiflora showed synergistic effect with LC50 of 38 ppm and EOs from L. chevalieri and C. schoenanthus showed antagonistic effect against larvae with LC50 of 100.84 ppm. On the other hand, EOs combinations showed additive effect on all adults. This study describes the potential of using EOs and their synergistic mixtures as potential insecticide(s) as a safer alternative to synthetic insecticides.

Larvicidal Activities and Synergistic Effects of Essential Oils against Anopheles funestus and Culex quinquefasciatus (Diptera: Culicidae) from Kisumu, Kenya

Rapid development of resistance in vector mosquitoes to synthetic insecticides is a major challenge for malaria control. The use of plant-derived essential oils (EOs) is an attractive strategy in controlling mosquito populations because they are environmentally safe and may have a lower chance of developing resistance. This study assessed the larvicidal activities of EOs from Lantana camara, Lippia multiflora, Lippia chevalieri, and Cymbopogon schoenanthus against Anopheles funestus and Culex quinquefasciatus. The 3rd–4th instar larvae were tested using a World Health Organization (WHO)-modified protocol to evaluate larval mortality 24 h after exposure to EOs and their binary combinations. Culex quinquefasciatus larvae were more susceptible to EOs than An. funestus larvae. For Cx. quinquefasciatus, the lethal concentrations at 50% mortality (LC50s) of EOs from C. schoenanthus, L. multiflora, L. camara, and L. chevalieri were 23.32, 27.24, 38.54, and 54.11 ppm, respectively; whereas for An. funestus, the EO LC50s were 120.5, 67.5, 49.21, and 105.74 ppm, respectively. Synergistic effects were observed using EOs from C. schoenanthus + L. multiflora (LC50 = 44.05 ppm) on An. funestus, while L. camara + L. chevalieri (LC50 = 33.16 ppm), L. chevalieri + C. schoenanthus (LC50 = 12.08 ppm), and L. multiflora + L. chevalieri (LC50 = 20.61 ppm) were synergistic for Cx. quinquefasciatus. These results indicate the potential of EOs derived from local plants and their binary combinations as botanical larvicides. The EOs could be used as future ecofriendly agents to control these vectors.

In-Vitro Evaluation of Some Traditional Medicinal Plants on Calcium Oxalate Urolithiasis

The prevalence of urolithiasis in Middle East countries is predominantly high. Traditional medicinal plants play a role in the prevention and management of urolithiasis. The effect of Petroselinum crispum, rind of Citrus sinensis L., rind of Citrus limon L., Ammi visnaga (L.) LAM., Tamarindus indica L., Nigella sativa L., Cymbopogon proximus Hochst. ex A. Rich., Hibiscus sabdariffa L., Hordeum vulgare L., and Cymbopogon schoenanthus (L.) Spreng. on calcium oxalate crystallization was investigated in-vitro. The antispasmodic activity on acetylcholine-induced contraction in rat ileum was also screened ex-vivo. A significant reduction in the mean diagonal of calcium oxalate crystals was observed for P. crispum, C. proximus, N. sativa, and C. limon (4.41 mm, 4.71, 5.44, and 5.67 mm, respectively) compared to the negative control (12.19 mm). H. sabdariffa exhibited antinucleation effect however, P. crispum showed a marked inhibition of calcium oxalate aggregation at 10 mg/mL after 60 min compared to the negative control. A remarkable ex-vivo antispasmodic activity was observed for C. proximus, C. schoenanthus, and A. visnaga extracts. Our results provide scientific evidence for the traditional use of the studied plant-derived products as potential therapies for calcium oxalate urolithiasis.

Antifungal and Antiaflatoxinogenic Effects of Cymbopogon citratus, Cymbopogon nardus, and Cymbopogon schoenanthus Essential Oils Alone and in Combination.

The antifungal and antiaflatoxinogenic activities of the essential oils (EOs) from the leaves of Cymbopogon schoenanthus, Cymbopogon citratus, Cymbopogon nardus, and their pair combinations were investigated. Antifungal susceptibility and the efficacy of paired combinations of EOs were assessed using agar microdilution and checkerboard methods, respectively. Identification and quantification of chemical components of the EOs were carried out by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector (GC-MS and GC-FID), respectively. Aflatoxins were separated and identified by High-Performance Liquid Chromatography (HPLC) and then quantified by spectrofluorescence. The EO of C. nardus exhibited the highest inhibitory activity against Aspergillus flavus and Aspergillus parasiticus. The combination of C. citratus and C. nardus and that of C. nardus and C. schoenanthus exhibited a synergistic effect against Aspergillus flavus and Aspergillus, respectively. Both C. citratus and C. schoenanthus EOs totally inhibited the synthesis of aflatoxin B1 at 1 µL/mL. C. citratus blocked the production of aflatoxins B2 and G2 at 0.5 µL/mL. Both C. citratus and C. schoenanthus totally hampered the production of the aflatoxin G1 at 0.75 µL/mL. The combination of C. citratus and C. schoenanthus completely inhibited the production of the four aflatoxins. The study shows that the combinations can be used to improve their antifungal and antiaflatoxinogenic activities.

Effect of Topical Sports Cream Containing Cymbopogon schoenanthus on Acute Recovery Markers Following Exercise-Induced Muscle Fatigue in Competitive Athletes: A Pilot Study

Background: Muscle fatigue following high-intensity or repetitive training causes reduced muscle strength, restriction of blood flow, and increased muscle pain. The application of topical sports cream (TSC) as a recovery method has recently gained attention. However, few studies have investigated the effects of topical sports cream containing Cymbopogon schoenanthus (CS) on acute recovery markers. This study aimed to examine the effects of the acute application of a TSC containing CS after exercise-induced muscle fatigue on acute recovery markers. Methods: Ten taekwondo athletes (male: 5, female: 5) participated in this study. In a crossover design with 2-week intervals, participants were randomly assigned to two clinical trial groups: TSC and placebo cream (PC). Isokinetic dynamometers were used to create exercise-induced muscle fatigue, and the subjects repeatedly performed external and internal shoulder rotations. TSC containing CS was applied to the shoulder muscles of the subjects after the exercise. Maximum voluntary isometric contraction, muscle pain, blood flow, and skin temperature were measured before, during, immediately after, 30 min after, and 60 min after exercise. Results: A significant interaction effect was found in blood flow between time and group (p = 0.032, ηp2 = 0.157). However, there was no statistically significant interaction effect between time and group for maximum voluntary isometric contraction (MVIC), muscle pain, and skin temperature (p > 0.05). Conclusions: Acute application of TSC containing CS is effective in increasing blood flow during the recovery period following exercise-induced muscle fatigue.

Nuclear magnetic resonance characterizes metabolic differences in Cymbopogon schoenanthus subsp. proximus embryogenic and organogenic calli and their regenerated shoots

Nuclear magnetic resonance characterizes metabolic differences in Cymbopogon schoenanthus subsp. proximus embryogenic and organogenic calli and their regenerated shoots

Antimicrobial Activity of Some Sudanese Medicinal Plants Against its Pollutant Isolated Bacteria

<b>Background and Objective:</b> Medicinal plants have been known to cure many diseases due to the presence of active bio constituents, the goal of this study to detect and evaluate the effectiveness of antimicrobial activity of some Sudanese medicinal plants. <b>Materials and Methods:</b> Methanolic extracts of the following types of local medicinal plants <i>Artemisia herba-alba</i>,<i> Cyperus rotundus</i>,<i> Cymbopogon schoenanthus </i>sb<i> </i>sp.<i> Proximus</i>,<i> Trigonella foenum-graecum</i>,<i> Nigella sativa</i>,<i> Hyphaene thebaica</i>,<i> Nauclea latifolia</i> and <i>Ziziphus spina-christi</i> were tested against eight types of bacteria that were isolated from the same plants as their pollutants. Cup-plate method was used and then the inhibition zone of each plant was measured and compared with the inhibitory zone of some antibiotics used for the same isolates. <b>Results:</b> Methanol extracts of some plant species showed antibacterial activity against most of the studied bacterial species. <i>Cymbopogon schoenanthus </i>ssp.<i> Proximus </i>showed antibacterial activity against most isolated bacterial species in comparison with commercial antibiotics used. <b>Conclusion:</b> According to the findings of this research, severalmedicinal plants have efficacy and effect on certain types of bacteria and are superior or comparable to certain types of antibiotics. When compared to the other medicinal plants used in this study<i>, Cymbopogon schoenanthus </i>sbsp. <i>proximus </i>has the highest activity on most types of Gram-positive and Gram-negative bacteria, as well as the superiority of some antibiotics.

Green corrosion inhibitor: Cymbopogon schoenanthus extract in an acid cleaning solution for aluminum brass

Abstract The purpose of this study was to see if Cymbopogon schoenanthus aerial extract (CSA extract) could reduce the corrosion of aluminum brass in acid cleaning solutions in the distillation plant. For this assessment, measurements of weight loss and polarization technique have all been used. We discovered that at 250 ppm, the efficiency of CSA extract was excellent (97%). Polarization assessments confirmed that the organic compounds in CSA extract were effective mixed-type corrosion inhibitors. HPLC and FTIR analysis were used to explore the key chemical components of CSA extract. CSA extract caused the corrosion process to have a higher energy barrier. Observations of SEM and FT-IR spectra confirmed that CSA extract prevents corrosion attacks at the aluminum brass’s surface.

Effects of Essential Oils on in Vitro Growth of Fungi Cladobotryum dendroides and Mycogone perniciosa Infecting Button Mushroom

Abstract The aim of the studies was to investigate the effect of camel grass, lavender, patchouli, peppermint and tea tree essential oils, and their mixtures on the in vitro growth of pathogenic fungi Cladobotryum dendroides and Mycogone perniciosa, occurring in the cultivation of button mushroom (Agaricus bisporus). The mycelial growth of the tested pathogens was evaluated on PDA medium. Essential oils were added in three doses: 0.25; 0.5 and 1 mg·cm–3 of PDA medium. Camel grass and peppermint essential oils applied at the highest dose inhibited completely the in vitro growth of C. dendroides mycelium. Lavender oil used at the amount of 1 mg·cm–3 reduced the growth of the pathogen by 90 %. In the case of M. perniciosa the complete inhibition of the pathogen’s growth was observed after the addition of camel grass oil to PDA medium, irrespective of a dose, and lavender oil at the doses of 0.5 and 1 mg·cm–3. The efficacy of the tested mixtures against M. perniciosa was high. Generally, all mixtures of essential oils, irrespective of a dose, completely controlled the growth of the pathogen. The complete inhibition of the growth of C. dendroides was observed only on the medium with the addition of the mixture of camel grass and peppermint oils at the highest dose. The conducted research showed that natural essential oils due to their antifungal properties could be useful in the Integrated Disease Management for the protection of button mushroom against diseases. They could be an effective alternative to synthetic chemical fungicides.

Fungal Contamination of Some Medicinal Plant Materials Sold at Omdurman Local Market, Khartoum State, Central Sudan

Plants have long been used as herbal medicines in many countries. However, microbial contamination of these medicines may affect human health. In the present study fifteen medicinal plants namely, Acacia nilotica ssp. nilotica, Trigonella foenum-greacum, Nigella sativa, Hyphaene thebaica, Nauclea latifola, Cyperus rotundus, Cymbopogon schoenanthus spp, proximus, Artemisia herba-alb, Cassia acutifolia, Solenostemma argel, Tamarindus indica, Ziziphus spina-christi, Lepidium sativum, Foeniculum vulgare and Coriandrum sativum were evaluated for their fungal contamination. The pour plate method was used to cultivate serially diluted portions of the medicinal plant material investigated. The colonies of fungi were identified morphologically according to form and pigment. They were observed microscopically through Lactophenol cotton bluestaining. The identified fungal isolates were consist of three fungal species, the most dominant fungi were Aspergillus nigar and Aspergillus flavus. Penicillium ssp is least one. The total fungal counts ranged from 00x101 cfu/g (Cymbopogon schoenanthus spp.proximus, Trigonella foenum-greacum, Artemisia herba alb, Lepidium satinum , Nigella sativa Cassia acutifolia and Naucle latifola) to 11x105cfu/g (Cyperus rotundus).. The highest total fungal load was found in Cyperus rotundus The levels of contamination varied greatly between the commercially available plant samples investigated.

Effect of exogenous methyl jasmonate on in vitro propagation, metabolic profiling and proximadiol production from Cymbopogon schoenanthus subsp. proximus

Effect of exogenous methyl jasmonate on in vitro propagation, metabolic profiling and proximadiol production from Cymbopogon schoenanthus subsp. proximus

Therapeutic potential of Cymbopogon schoenanthus (L.) developed into nanoparticle technology


 Introduction: One of plants that may have therapeutic potential is the Cymbopogon schoenanthus (L.) Spreng, also known as camel grass. 
 Aim: This review aims to investigate and gather comprehensive information about camel grass plants and their potential to be developed into a nanotechnology drug delivery system. 
 Methods: This review examined a variety of online literature. 
 Results: It was found that camel grass contains essential oil such as piperitone. Piperitone is efficacious as an antioxidant, antimicrobial and anti-inflammatory, in addition to other properties . The development of camel grass essential oil into lipid-based nanotechnology preparations can improve its bioavailability, solubility, and stability, thereby improving its potential effectiveness.

Effect of Different Parameters on Volatile Composition of the Different Parts of Cymbopogon schoenanthus L. Spreng (Poaceae) Extracted by Headspace Solid-phase Microextraction and Hydrodistillation

In the present study, volatiles from different organs (leaves, roots, and spikelets) of Cymbopogon schoenanthus L. Spreng were investigated. The samples were collected from Oued Sbaa, El-Menia (Algeria) and analyzed for the first time by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). In addition to this green technique, cryogenic grinding using liquid nitrogen was performed on all samples to minimize the volatile loss. Results of HS-SPME (adsorption and affinity-based) were compared with those of essential oils extracted by hydrodistillation (heating-based) as a conventional extraction method and revealed remarkable variability. Findings showed also similarities in leaves and spikelets volatile mainly composed of monoterpene and sesquiterpene hydrocarbons; however, the volatile profile of the roots presented a specific composition dominated by sesquiterpene hydrocarbons and oxygenated sesquiterpenes. The effects of HS-SPME extraction parameters such as the temperature of headspace (45°C and 55°C), type of fiber coating (PDMS and PDMS/CAR), and the salting-out effect (sodium chloride at 20 %) were also studied. The results display that salt adding has considerably reduced the extraction efficiency of the analytes. Temperature presented two opposing effects on the composition. PDMS/CAR fiber revealed a great performance over PDMS. The multivariate statistical analysis including the hierarchical cluster analysis (HCA) and the principal component analysis (PCA) were used and showed many differences amongst the selected plant parts and the studied parameters. The results showed the possibility of HS-SPME-GC-MS application as a complementary tool for the characterization of the chemical composition of C. schoenanthus L. Spreng.

Agronomic Responses of Cymbopogon schoenanthus L. Spreng., a Sudanese Forage Grass Grown under Compost for a Bio-Ecological Pasture in the Southern Benin

Promoting ecological and organic agriculture (including livestock) requires biological resources and alternatives. Cymbopogon schoenanthus is a sudano-sahelian grass species whose crude leaf essential oils, in addition to their antifungal, antimicrobial, antibacterial and acridifuge or acridicide properties, can be an alternative to chemical insecticides in preventing pests and diseases that limit crops productivities. This study tests the agronomic performances of Cymbopogon schoenanthus grown under three doses of compost. Stumps collected from the Park W of Niger were transplanted to the experimental farm of the Faculty of Agronomic Sciences of University of Abomey-Calavi in the Southern Benin. The experimental design was a complete randomized block with treatments (0 ton per hectare (i.e., control), 5 tons per hectare and 10 tons per hectare of compost) in four replicates. Plants responses to the compost application throughout traits such as heights, number of tillers per plant, number of flowering tillers and dry aerial biomass production, were analyzed with a one-way ANOVA using STATISTICA 9.0. The results show significant responses of the aerial organs of C. schoenanthus to organic fertilization (p<0.05) with the best performance under 5 tons of compost per hectare: height growth in magnitude of 12.72%, number of tillers multiplied in 146.06% and aerial dry biomass in 178.32%. However, fertilization did not influence flowers appearance. Further studies are required for assessing foliar, nutritional quality and essential oil responses to the compost application in order to sustainably promote small ruminants’ organic production.

Citral-Containing Essential Oils as Potential Tyrosinase Inhibitors: A Bio-Guided Fractionation Approach.

Excessive melanin production causes serious dermatological conditions as well as minor aesthetic problems (i.e., freckles and solar lentigo). The downregulation of tyrosinase is a widespread approach for the treatment of such disorders, and plant extracts have often proven to be valuable sources of tyrosinase inhibitors. Citral (a mixture of neral and geranial) is an important fragrance ingredient that has shown anti-tyrosinase potential. It is highly concentrated in the essential oils (EOs) of Cymbopogon schoenanthus (L.) Spreng., Litsea cubeba (Lour.) Pers., Melissa officinalis L., and Verbena officinalis L. However, only L. cubeba EO has been investigated for use as a potential skin-whitening agent. This work evaluates the in vitro tyrosinase inhibitory activity of these EOs and studies, using bio-assay oriented fractionation, whether their differing chemical compositions influence the overall EO inhibitory activities via possible synergistic, additive, and/or competitive interactions between EOs components. The inhibitory activity of C. schoenanthus EO and that of M. officinalis EOs, with negligible (+)-citronellal amounts, were in-line with their citral content. On the other hand, L. cubeba and V. officinalis EOs inhibited tyrosinase to considerably greater extents as they contained β-myrcene, which contributed to the overall EO activities. Similar observations were made for M. officinalis EO, which bears high (+)-citronellal content which increased citral activity.

Efficacite des bioinsecticides a base de l’huile essentielle de Cymbopogon schoenanthus (L.) spreng contre les punaises rouges (Dysdercus voelkeri, schmidt) en culture cotonniere au Togo

Currently, the fight against red bugs, a pest of the cotton plant, is limited to the use of synthetic chemical insecticides. Many of the products used are persistent and their high toxicity to human health and the environment is of concern. In the search for alternatives to synthetic chemical insecticides, the aim of this research work was to evaluate the insecticidal potential of aqueous emulsions based on the essential oil of Cymbopogon schoenanthus(L.) against Dysdercus voelkeri, one of the redoubtable pests of cotton plant in Togo. Aqueous emulsions at different concentrations were used in phytosanitary treatments on cotton crop compared to vulgarized binary insecticides (lambdacyhalothrin/profenofos 15/300 gha-1and cypermethrin/acetamiprid 36/8 gha-1). D. voelkeri counts on target plants of each elementary plot revealed that the highest dose of the emulsion (6%) of C. schoenanthus essential oil and the control (vulgarized insecticide)were more effective with low bug population densities of 7.14± 1.46 and 4.86± 1.84 bugs/plant,respectively. On the contrary,the other doses (4 and 2%) of emulsions based on C. schoenanthus essential oil had in their plots respectively 39.57 ± 5.81 and 45.28 ± 3.92 bugs/plant and the control (55.71± 5.23 bugs/plant). Health analysis of the young cotton bolls that fell under the cotton plants revealed that the highest dose of the emulsion (6%) and the control reduced stings by 71.40 and 72.33 % respectively, compared to the control. Stings reduction rates in plots with treatments of 4 and 2% of the emulsion were low with rates of 55.32and22.83%,respectively. These results clearly show that the aqueous emulsion formulated and tested in the study can significantly reduce attacks of these pests. This study shows the possibility of using the essential oil of C. schoenanthus as a raw material in the formulation of biopesticide as an alternative to synthetic chemical insecticides in the control of cotton plant red bugs in Togo.