Graveolens Essential Oil Research Articles

Biodegradation of Residues from the Palo Santo (Bursera graveolens) Essential Oil Extraction and Their Potential for Enzyme Production Using Native Xylaria Fungi from Southern Ecuador

The degradation dynamics of lignin and cellulose were analyzed by means of a solid state biodegradation experiment, using residues from the essential oil extraction of the Palo Santo tree (Bursera graveolens). As such, two native Xylaria spp. and an exotic mushroom Trametes versicolor were incubated on the spent substrate (Residues of B. Graveolens, BGR’s). The relatively high lignin and cellulose contents of the BGRs (9.1% and 19%, respectively) indicated the potential of this resource for the production of methane (biogas) and ethanol. However, the degradation of the lignin and cellulose content could be traced back to the relatively high activity of the enzymes laccase, cellulase, and xylanase, produced by the fungi. The results showed that laccase (30.0 U/L and 26.6 U/L), cellulase (27.3 U/L and 35.8 U/L) and xylanase (189.7U/L and 128.3 U/L) activities of Xylaria feejeensis and Xylaria cf. microceras were generally higher than T. versicolor (9.0 U/L, 29.5 U/L, 99.5 U/L respectively). Furthermore, the total carbon (TC: 47.3%), total nitrogen (TN: 1.5%), total phosphorus (TP: 0.2%) and total potassium (TK: 1.2%) dynamics were analyzed during the experiment and their importance for the degradation process highlighted. The results of this work might serve as guidance for future studies in dry forest areas, while furthering the understanding of the potential use of native fungi as ecologic lignocellulosic decomposers and for industrial proposes.

Colletotrichum Gloesporioides Inhibition In Situ by Chitosan-Ruta graveolens Essential Oil Coatings: Effect on Microbiological, Physicochemical, and Organoleptic Properties of Guava (Psidium guajava L.) during Room Temperature Storage.

Guava is a fruit appreciated worldwide for its high content of bioactive compounds. However, it is considered a highly perishable fruit, generally attacked by pathogenic species such as the fungi Colletotrichum gloeosporioides, which causes anthracnosis. To diminish the losses caused by pathogenic fungi, coatings of chitosan (CS) with Ruta graveolens essential oil (RGEO) in different concentrations (0.5, 1.0, 1.5% v/v) were applied in situ and their effects on the physical properties and microbiological quality of the guavas were studied. The CS+RGEO coated fruits exhibited better physicochemical behavior and lower microbiological decay as compared to the uncoated guavas, demonstrating the effectiveness of the coatings, especially those with 1.5% of RGEO content. All the fruits coated had greater acceptance and quality than the controls, being more those with essential oil incorporation. In situ investigation of C. gloesporioides infection of guavas demonstrated that the CS+RGEO coated guavas showed a high percentage of inhibition in the development of anthracnose lesions. In the present investigation, an alternative method has been proposed to extend the stability of the guavas fruit up to 12 days with application in the food industry.

Anti-dermatophyte activity of Pelargonium graveolens essential oils against dermatophytes

BackgroundPelargonium graveolens as valuable aromatic plant is used for extracting the essential oil, which their biological effects such as antioxidant, antimicrobial, anti-inflammatory and wound healing effects have been confirmed.MethodsIn this study, the anti-dermatophyte effects of nine P. graveolens essential oils were confirmed against Microsporum canis, M. gypseum, Trichophyton rubrum, T. mentagrophytes, and T. schoenleinii by mycelium growth inhibition percent and micro-broth dilution assays. The chemical composition of essential oils was determined by GC and GC-MS.ResultsThe main components of P. graveolens essential oils and their percentages changed from one sample to others. The highest growth inhibition percent and the lowest MIC values of P. graveolens essential oils for dermatophytes were for E20 with 95% geraniol content, followed by E4 and E14 with highest amounts of geraniol (21%) and citronellol (30–35%) contents.ConclusionTherefore, the use of P. graveolens essential oils with high geraniol and citronellol is recommended for dermatophytes. Animal models studies of dermatophytes are required to confirm the efficacy and application of P. graveolens essential oils in human studies.

Antimicrobial activity, antiaflatoxigenic potential and in situ efficacy of novel formulation comprising of Apium graveolens essential oil and its major component

The present study reports the formulation of Apium graveolens essential oil (AGEO) with its major components linalyl acetate (LA) and geranyl acetate (GA) (1:1:1) as a novel green preservative for protection of postharvest food commodities from fungal infestations, aflatoxin B1 (AFB1) secretion, free radical generation and lipid peroxidation. The essential oil based novel formulation displayed considerable inhibitory action against fourteen food borne molds responsible for deterioration of stored food commodities, in addition to the most toxigenic strain of Aspergillus flavus (AFLHPR14) isolated from fungal and aflatoxin contaminated rice seeds. The observed higher efficacy of designed formulation was due to the synergistic action of essential oil and its major components. Fungal plasma membrane was recorded as the possible target site of antifungal action of the formulation as revealed through reduction in membrane ergosterol content, increased intracellular propidium iodide (PI) fluorescence and enhanced leakage of cellular ions (sodium, potassium, calcium) and 260, 280 nm absorbing materials. Further, inhibition of methylglyoxal (an aflatoxin inducer) confirmed the aflatoxin inhibitory potential of novel formulation based on essential oil and its major components. High antioxidant potential as observed through DPPH and ABTS·+ radical scavenging assay, improved phenolic content, considerable inhibition of lipid peroxidation in stored rice seeds, in situ efficacy on AFB1 inhibition in food system under storage container system, acceptable sensorial characteristics and favorable safety profile during animal trials suggest the recommendation of the designed formulation for large scale application as green preservative by food and agriculture based industries against fungal and aflatoxin contamination of stored commodities.

Physicochemical, microbiological, and sensory characteristics of probiotic yogurt enhanced with Anethum graveolens essential oil

AbstractIn the present work, physicochemical, sensory characteristics and viability of Bifidobacterium bifidum and Lactobacillus casei of probiotic yogurt using dill (Anethum graveolens) essential oil (DEO) (50 and 100 ppm) were investigated at 4°C for 21 days. Alterations in amount of fat and protein of yogurt treatments during storage time were not significant. The viability of B. bifidum and L. casei increased up to the 2nd week of storage and then decreased by the end of the storage period. Generally, samples with incorporated 100 ppm DEO had the highest number of probiotic bacteria on the last day of storage, 7.81 and 7.92 CFU/g for L. casei and B. bifidum, respectively. pH and titratable acidity values were decreased and increased, respectively, over the time for all samples. Yogurt with incorporated 100 ppm DEO achieved higher sensory scores compared to other yogurt samples. Therefore, the current results confirmed that the addition of probiotic and DEO improved the physicochemical and sensory characteristics of yogurt.Practical ApplicationsYogurt undergoes sensory, chemical changes and microbial growth during refrigerated storage. Bifidobacterium bifidum and Lactobacillus casei are generally applied as probiotic species in milk products. Dill essential oil (DEO) is used in food industries to extend the shelf life of the foods with desired organoleptic properties. This work recommends that DEO can be successfully used as a safe and natural source in the production of probiotic yogurt.

Antifungal Activity of Pelargonium graveolens Essential Oil and its Fractions Against Wood Decay Fungi

In order to valorize Moroccan aromatic and medicinal plants, this study focused on both the chemical characterization and the study of the antifungal activity of Pelargonium graveolens essential oil and its fractions against four fungi that are responsible for wood decay (Coniophora puteana, Coriolus versicolor, Poria placenta and Gloeophyllum trabeum). The essential oils were analyzed by Gas chromatography/Mass spectrometry (GC/MS) and evaluated for antifungal activity, using the macrodilution method for the determination of EC50. The GC/MS essential oil analysis has led to the identification of 54 components. Citronellol (25.24 %), geraniol (23.36 %), citronellyl formate (8.35 %), linalool (7.11 %), β-eudesmol (6.13 %), geranyl formate (4.26 %) and iso-menthone (3.37 %), were identified as the major components. Fractions 1, 2 and 3 essential oils have displayed qualitative similarities with the EO sample, and quantitative differences among the relative percentages of major compounds were observed. A significant difference (p < 0.0001) was shown in main compounds of fraction 3 obtained by fractional distillation. P. graveolens essential oil has inhibited all fungi with a value of EC50 between 0.255 to 1.022 mg/mL. The EC50 values of fractions 1 and 2 are ranging from 0.292 to 1.022 mg/mL. The fraction 3 exhibited a great antifungal activity against all tested fungi. These results support the potential use of P. graveolens essential oils and its fractions for wood protection against wood decay fungi.

Phytochemical Study and Antidepressant Effect of Essential Oil of Apium graveolens L.

Background and Purpose: Depression is a common and debilitating disease.The aim of this study was to investigate the chemical composition of Apium graveolens essential oil and its anti-depressant effect in mice and the effect on motor balance, serum and brain antioxidant capacity.&#x0D; Materials and Methods: 60 mice were randomly divided into 6 groups (N=10), Control, reserpine 5 mg/kg IP, reserpine + fluoxetine 20mg/kg, reserpine + essential oil (50, 75 and 100 mg/kg). The intervention group received 5 mg/kg reserpine and 18 hours later, essential oil (50, 75 and 100 mg/kg). Assessment of depression done with forced swimming and open field tests and motor balance with a Rotarod. Serum and brain antioxidant capacity and malondialdehyde levels were measured.&#x0D; Results: Reserpin increased the immobilization time in the forced swimming test, the number of motor units in the open field test, serum and brain malondialdehyde and reduced the antioxidant capacity and the motor balance. Fluoxetine and essential oil of Apium graveolens 50 and 75 mg/kg reduced the time of immobilization time, number of motor units, serum and brain malondialdehyde and increased serum and brain antioxidant capacity and motor balance. Apium graveolens essential oil 100 mg/kg increased serum antioxidant capacity and reduced number of motor units.&#x0D; Conclusion: Chemical compounds of essential oil of Apium graveolens have antioxidant, anti-inflammatory and regulating of chemical neurotransmitters properties that are known mechanisms of depression.

Phytochemical Study and Antidepressant Effect of Essential Oil of Apium graveolens L.

Background and Purpose: Depression is a common and debilitating disease.The aim of this study was to investigate the chemical composition of Apium graveolens essential oil and its anti-depressant effect in mice and the effect on motor balance, serum and brain antioxidant capacity.&#x0D; Materials and Methods: 60 mice were randomly divided into 6 groups (N=10), Control, reserpine 5 mg/kg IP, reserpine + fluoxetine 20mg/kg, reserpine + essential oil (50, 75 and 100 mg/kg). The intervention group received 5 mg/kg reserpine and 18 hours later, essential oil (50, 75 and 100 mg/kg). Assessment of depression done with forced swimming and open field tests and motor balance with a Rotarod. Serum and brain antioxidant capacity and malondialdehyde levels were measured.&#x0D; Results: Reserpin increased the immobilization time in the forced swimming test, the number of motor units in the open field test, serum and brain malondialdehyde and reduced the antioxidant capacity and the motor balance. Fluoxetine and essential oil of Apium graveolens 50 and 75 mg/kg reduced the time of immobilization time, number of motor units, serum and brain malondialdehyde and increased serum and brain antioxidant capacity and motor balance. Apium graveolens essential oil 100 mg/kg increased serum antioxidant capacity and reduced number of motor units.&#x0D; Conclusion: Chemical compounds of essential oil of Apium graveolens have antioxidant, anti-inflammatory and regulating of chemical neurotransmitters properties that are known mechanisms of depression.

Antifungal activity of Pelargonium graveolens essential oils from different geographical locations against Candida albicans

Antifungal activity of Pelargonium graveolens essential oils from different geographical locations against Candida albicans

Biochemical and Histopathological Evidence for Beneficial Effects of Pelargonium graveolens Essential Oil on the Rat Model of Inflammatory Bowel Disease

Background and objectivesPelargonium graveolens L'Her. is an essential oil bearing plant used in traditional medicine of Iran for the treatment of inflammatory disease and pain, anxiety, sadness and also for the relief of gastrointestinal symptoms. Its pharmaceutical product is presently used in Iran for the treatment of depression disorders. Since colitis is a brain-gut interactive disorder, the authors were prompted to investigate the preventive effect of P. graveolens essential oil product (Deproherb®) to control the induced inflammatory bowel disease (IBD) in rats.MethodsExperimentally ulcerative colitis was induced by acetic acid in animals pretreated with three different doses of Deproherb® (100, 200 and 400 mg/kg, p.o.) for five consecutive days. Anti-inflammatory effects of Deproherb® were compared with orally administrated sulfasalazine (4 mg/kg). Biochemical [Myeloperoxidase (MPO) activity] and macroscopic and microscopic examinations of the colon was performed. Deproherb® was also analyzed by GC and GC/MS in order to identify the potentially responsible compounds for observed property.ResultsThe obtained results indicated that the activity of MPO increased in acetic acid-treated groups, while it was recovered by pretreatment with Deproherb® (100-400 mg/kg) and sulfasalazine. All doses of Deproherb® and sulfasalazine-treated groups showed significant lower score values of macroscopic and microscopic characters when compared to the acetic acid-treated group. It was concluded that Deproherb® inhibited the acetic acid toxic reactions in the rat bowel.ConclusionsThe present study proved the anti-inflammatory potential of Deproherb® Oral Drop, in the experimentally induced colitis. Proper clinical investigations are suggested to confirm the observed activities in human.

GROWTH PERFORMANCE, FEED EFFICIENCY AND BLOOD PARAMETERS IN NILE TILAPIA EXPOSED TO MERCURY TOXICITY AND ITS REDUCTION BY USING DIETARY SUPPLEMENTATION OF ESSENTIAL OILS

A 112-day feeding trial was performed to investigate the toxic effects of mercury on Nile tilapia (Oreochromis niloticus) and attempt to detoxify these drastic effects by using dietary supplementation of citronella (Cymbopogon nardus) and geranium (Pelargonium graveolens) (GEO) essential oils. Fish were divided into four groups, each group was stocked into 3 aquaria, each one contains 10 fish. The first group was fed on basal diet without mercury, the second group was fed on basal diet containing 50 ppm mercury as mercuric chloride (HgCl2), each of third and fourth group was treated with 50 ppm HgCl2 and supplemented with 400 mg/kg diet citronella or geranium oils, respectively. Live body weight at 16 week was significantly increased by 40.76%, 22.64 and 12.41%, respectively in each of fish group fed diets without mercury (basal diet), fish group fed a diet contaminated with mercury and supplemented with citronella oil and fish group fed a diet contaminated with mercury and supplemented with geranium oil when compared with those fed diet contaminated with mercury. Also, daily weight gain at 0-16 weeks significantly increased by 51.38, 28.44 and 15.60%, respectively. Feed conversion at 0-16 weeks significantly improved by 29.56, 16.92 and 14.27%, in fish group fed diets without mercury (basal diet), fish group fed a diet contaminated with mercury and supplemented with citronella oil and fish group fed a diet contaminated with mercury and supplemented with geranium oil, respectively, when compared with those fed diet contaminated with mercury. Serum total protein and albumin significantly increased, while serum ALT, AST, urea-N and Createnine were decreased in fish groups fed diets without mercury. Also serum total protein increased in fish groups fed diet contaminated with mercury and treated with citronella or geranium oil than those fed diet contaminated with mercury. Residual of mercury significantly decreased (P<0.001) by 29.53 and 31.49 in liver and muscles of fish group fed a diet contaminated with mercury and supplemented with citronella oil, respectively. Also in fish group fed a diet contaminated with mercury and supplemented with geranium oil decreased by 41.45 and 47.24, respectively. Based on the obtained results it could be concluded that, growth rate and feed conversion improved by dietary essential oils supplementation.

Actividad larvicida de aceites esenciales y extractos de plantas colombianas frente a Culex quinquefasciatus (Díptera: Culicidae)

Los aceites esenciales y extractos de plantas,cultivadas de forma orgánica en la finca El Limonal Piedecuesta-Santander, Colombia, obtenidos por hidrodestilación asistida por microondas y percolación, se caracterizaron por cromatografía de gases acoplada a espectrometría de masas. La actividad insecticida se evaluó frente a larvas en tercer instar de Culex quinquefasciatus y en la enzima acetilcolinesterasa. La toxicidad se determinó en el modelo del pez cebra (Danio rerio). De ellos, el aceite esencial de Ruta graveolens fue el que presentó la mejor actividad larvicida, con CL50 7.20±0.19 μg/mL, una moderada inhibición de la enzima con IC50 44.98±1.1 μg/mL y moderada toxicidad con CL50 13.33±0.59 mg/L.

Effectiveness of topical administration of Anethum graveolens essential oil on MRSA-infected wounds

Medicinal plants are conventionally used for wound healing, but their action mechanisms are still unknown. The present study evaluated the effect of topical administration of ointment containing dill (Anethum graveolens) essential oil (DEO) in the management of apoptosis and cell proliferation during MRSA-infected experimentally induced wound healing process in BALB/c mice model. The GC-FID and GC-MS techniques were used to analyze chemical composition of the essential oil. The mice were randomly divided into four treatment groups including negative control (sham), 2% and 4% DEO and mupirocin®-treated animals. The full-thickness excisional wounds were inoculated by 5 × 107 colony-forming units of MRSA. In order to assess the effect of different concentrations of DEO on wounds infection, wound area, bacterial count, histopathological, immunohistochemical and RT-PCR analysis were evaluated. The GC-MS analysis identified α-phellandrene (47.3%), p-cymene (18.5%) and carvone (14.1%) as the main compounds of the essential oil tested here. Administration of DEO prevented bacterial growth and also reduced wound area in comparison to the control group. Topical administration of DEO significantly reduced the inflammatory phase and accelerated re-epithelialization, angiogenesis, fibroblast and collagen deposition. Moreover, the DEO-treated animals exhibited higher expressions of Bcl-2, p53 caspase-3, VEGF and FGF-2 in comparison to the control and mupirocin®-treated groups (P < 0.05). Topical administration of DEO decreases the inflammatory phase by increasing p53 and caspases-3 expression. It triggers the proliferative phase by up-regulation of the Bcl-2, VEGF and FGF-2 expression and also up-regulates the collagen biosynthesis by enhancing the ERα expression level. Thus, ointment prepared from dill essential oil, in Iran, with its major compounds such as α-phellandrene, p-cymene and carvone can be used as an agent for accelerating the infected wound healing.

Mexican oregano (Lippia graveolens) essential oil-in-water emulsions: impact of emulsifier type on the antifungal activity of Candida albicans.

This study examined the impact of emulsifier type on the physicochemical characteristics and antifungal capacity of oregano oil-in-water emulsions: Tween 80, hydroxylated soy lecithin, and gum arabic. GC/MS analysis showed that the major components of the Lippia graveolens essential oils were thymol (31.7%), p-cymene (18.7%), and carvacrol (14.6%). The oil-in-water emulsions were made using ultrasonic technology in which thymol and carvacrol quantities were 12.26-13.67g/L and 5.6-6.2g/L, respectively. The droplet size of the emulsions followed the next descendent order: gum arabic > lecithin > T80. The zeta potential of the emulsions favored the stability against coalescence. Finally, the antifungal activity of the emulsions was evaluated, in which, 30µL/mL of gum arabic or hydroxylated soy lecithin emulsions inhibited the growth of Candida albicans. The result suggests that Mexican oregano essential oil emulsions can be used as an antifungal against of C. albicans.

Sensitivity of Entomopathogenic Fungi and Bacteria to Plants Secondary Metabolites, for an Alternative Control of Rhipicephalus (Boophilus) microplus in Cattle.

Boophilus (Rhipicephalus) microplus is a one host hard tick widespread in warm climates worldwide, responsible for great economic losses. To avoid resistance in ticks population, induced by the repeated administration of conventional acaricides and/or the presence of residues in the environment in meat and in milk, an alternative approach can be achieved using entomopathogenic microorganisms such as fungi and bacteria, or essential oils (EOs). The aim of the present study was to evaluate the in vitro sensitivity of Beauveria bassiana, Metarhizium anisopliae, Scopulariopsis sp, Bacillus thuringiensis and Proteus mirabilis to Eucalyptus globulus, Lavandula hybrida, Pelargonium graveolens EOs and to their main constituents such as lynalool, linalyl-acetate, geraniol, citronellol and 1,8 cineole. EOs has been chemically characterized by GC-MS. Fungal isolates were tested by a microdilution assay to achieve minimal inhibitory concentration (MIC) of both EOs and main components. The sensitivity of bacteria was evaluated by an agar disk diffusion. The results obtained show the feasibility of an integrate approach for an eco-friendly control of R. microplus by use of both entomopathogenic fungi and P. graveolens EO. L. hybrida could be an interesting alternative when B. bassiana is not employed. Conversely, a combined use of B. thuringiensis and EOs would not be advisable in the integrate control of ticks.

Chemical composition, antioxidative, antimicrobial and anti-cancer activities of Asteriscus graveolens (Forssk) essential oil

This work is devoted to the study of the chemical composition and the evaluation of the biological activities of essential oils (EOs) extracted from the flowers of Asteriscus graveolens Forssk. plant. The EO sample was obtained by hydrodistillation and the chemical composition analysis was performed using GC and GC/MS. The major chemical components characterizing the EO were cis-chrysanthenyl acetate (44.30%) and cis-8-acetoxychrysanthenyl acetate (33.70%). Antioxidant activity was determined using DPPH and Phosphomolybdenum tests. Although the EO presented a weak scavenging activity (420.16 mg/mL), it exhibited good reducing power using the Phosphomolybdenum assay (0.28 AAEC/mg). The most important antibacterial activity was noted for Bacillus cereus. The oil revealed a remarkable activity against the nine fungi species tested with percentage inhibition up to 94.12% for Fusarium culmorum (BTCR). More important, this work investigated for the first time the anticancer effect of this EO on two types of cancer cell lines (human liver carcinoma and Rat pheochromocytoma cell lines). The EO showed a high anticancer activity against both tumor cell lines comparing to the positive control.

Effect of cyclodextrins and Mexican oregano (Lippia graveolens Kunth) chemotypes on the microencapsulation of essential oil

Lippia graveolens (Kunth) essential oil (EO) contains the bioactive compounds carvacrol and thymol in different concentrations according to their chemotype. We evaluated the effect of the essential oil chemical composition, and different cyclodextrins (CD), β- and γ, on the microencapsulation process and its efficiency. Complex formation of L. graveolens EO with β-CD and γ-CD was determined by Scanning Electron Microscopy, X-Ray Diffraction, Thermogravimetric Analysis, and Fourier Transform Infrared Spectroscopy. Carvacrol and thymol concentrations in the γ-CD complexes were higher than in the β-CD complexes, as demonstrated by Gas Chromatography analysis. After 14 days of storage, carvacrol concentration in the β-CD complex remained similar to the initial values; while in the γ-CD complex the concentration was significantly reduced. In the case of thymol concentrations, no significant losses were observed after storage in the complexes obtained with β-CD or γ-CD. Our results confirmed that the microencapsulation of L. graveolens EO with CDs retained the bioactive compounds, carvacrol and thymol. Based on the amount of bioactive terpenes in these complexes and their relative stability, the best combinations to be used as delivery systems were the complexes formed between chemotypes thymol- γ-cyclodextrin and carvacrol-β-cyclodextrin.

Bio-efficacy of Ruta graveolens Essential Oil and Its Long Chain Aliphatic 2-Methlyl Ketone Constituents on the Egg Hatchability of Corcyra cephalonica (Stainton)

Plant essential oils are comprised of complex mixtures of components including minor constituents which determine the characteristic aroma and odour of the plant in contrast to synthetic insecticides based on the single products that act synergistically within plant as a defense strategy against herbivory and thus, it is likely that they are more durable towards evolving pest resistance. Hence, due to the evolutionary relationship with their functional roles and largely environmental friendly nature, these natural pesticides could be efficiently harnessed by the farmers in developing countries like Sri Lanka for post-harvest insect pest management. In that context, the present study was undertaken to assess the impact of the essential oil of Ruta graveolens and its long chain aliphatic 2-methyl ketone constituents (2-octanone, 2-nonanone, 2-decanone, 2-undecanone, 2-dodecanone and 2-tridecanone)on the egg hatchability of rice moth (Corcyra cephalonica), which is a serious lepidopteran pest of stored cereals, by exposing freshly laid eggs for various exposure time durations (6 hrs, 12 hrs and 24 hrs) in contact bioassays with different authentic concentrations under the laboratory conditions (29±20C and 84±2% R.H.). The concentrations of essential oil and its ketone constituents applied and the exposure time periods were significantly influenced the percentage egg hatchability of C. cephalonica. Accordingly, the inhibitory activity of egg hatching was significantly increased with increasing concentrations and time periods of exposure. Essential oil of R. graveolens at the concentration of 0.204 μl cm-2 and the even-chained congeners at the corresponding authentic concentrations (0.0009-0.0045μl cm-2) brought about 100% inhibition of hatching. Moreover, odd-chained congeners produced egg hatchability inhibition levels ranging from 60-90 % with the corresponding authentic concentrations (0.002-0.046μl cm-2) after 24 hr exposure time duration. Based on LC50 values, the eggs were significantly more susceptible to even-chained congeners (LC50= 0.00002 – 0.0015μl cm-2) than to the odd-chained congeners (LC50= 0.00008 – 0.0084μl cm-2) and the essential oil (LC50= 0.0096 μl cm-2). Regression equations and the probability values of lethal concentrations of essential oil and its ketone constituents revealed a significant and positive role in the population inhibition of C. cephalonica. The present study demonstrates the potential of R. graveolens essential oil and its ketone analogues to be exploited as natural grain protect ants which is of immense significance in view of overcoming or reducing environmental and toxicological implications of the unsystematic use of synthetic pesticides. Keywords: Corcyra cephalonica, Egg hatchability, Essential oil, Long chain aliphatic 2-methyl ketones, Ruta graveolens

Nema

The evaluation of the inhibition effect achieved by essential oils of dill ( Anethum graveolens L . ), oregano ( Origanum vulgare L.), juniper (Juniperus communis L.), sage ( Salvia officinalis L.) and winter savory ( Satureja montana L.) on seed germination and shoot growth of Johnson grass ( Sorghum halepense L.) was tested in laboratory. The chemical composition of essential oils was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major constituents were carvon (40.5%) and limonene (32.2%) for A. graveolens essential oil, carvacrol (73.7%) for O. vulgare essential oil, α-pinene (43.5%) for J. communis essential oil, b-thujone (32.7%) and camphor (17.2%) for S. officinalis essential oil, thymol (44.6%) and p- cimene (13.4%) for S. montana essential oil. The in vitro study on herbicidal activity was carried out on seed germination and shoots length of S. halepense ; A. graveolens , O. vulgare , S. montana essential oils significantly inhibited the germination and shoot length and their herbicidal activity could be attributed mainly to their high content of carvone, carvacrol and thymol. A. graveolens , O. vulgare and S. montana essential oils reduced seed germination by 61.5%, 52.7% and 47.3%, respectively, while J. communis and S. officinalis essential oils stimulated germination (7.7% and 2.2%, respectively). The shoot growth reduction for almost all essential oils, except J. communis essential oil , was more than 30%. The solution of A. graveolens , O. vulgare and S. montana essential oils exhibited more powerful bio-herbicidal effect compared to J. communis and S. officinalis essential oils on the germination and shoot growth of S. halepense .

The anti-candidal activity of Pelargonium graveolens essential oils against clinical isolates of Candida albicans

Objectives: Candida albicans as important opportunistic dimorphic fungi can cause the life threatening infections in humans. In this study, we evaluated the anticandidal activities of six samples of Pelargonium graveolens essential oils against 31 clinical isolates of C. albicans. Materials and methods: The anti-candidal activity was performed by disc diffusion and micro-broth dilution assays. The chemical compositions of essential oils were analyzed by Gas Chromatography (GC) apparatus. Results: P. graveolens essential oil samples with citronellol (7.7-43.7%) and geraniol (19.3-48.5%) showed the same anti-candidal activity in two different methods. There is no significant difference between the inhibition zone diameters (19.3-24.1 mm), and the MIC and MFC values (1.06-1.48 and 1.5-1.72 μl/ml) of essential oil samples with different percent of citronellol and geraniol. Conclusion: Therefore, P. graveolens essential oils can be used as anti-candidal agent for further studies.