Effect Of Essential Oil Research Articles

Survival, growth, and biogenic amine production of Enterococcus faecium FC12 in response to extracts and essential oils of Rubus fruticosus and Juniperus oxycedrus.

Enterococci are lactic acid bacteria (LAB) usually found as food contaminants in fermented products such as cheeses and fermented sausages. Due to their antibiotic resistance, the presence of virulence factors, and the ability to produce biogenic amines (BAs), the determination of these bacteria is crucial to assure food quality and safety. BAs production and consequent accumulation in foods can cause toxicological effects on human health. Plant phenolic compounds are promising alternatives to chemical preservatives and reflect consumers' demand for "green" solutions. In this study, the antimicrobial effect of blackberry (Rubus fruticosus) leaves and prickly juniper (Juniperus oxycedrus) needles, both as phenolic extracts (PE) and essential oils (EO), were evaluated against Enterococcus faecium FC12, a known tyramine-producing strain. The growth kinetics in the presence of sub-lethal concentrations of such plant derivatives were modeled (Gompertz equation) and BA production was monitored over time by HPLC. Moreover, flow cytometry (FCM) was used to study the effects of EOs and PEs on cell viability. The EOs showed a higher antimicrobial effect (especially R. fruticosus added at 0.75 mg/ml), determining an initial decrease of culturable cells followed by a recovery, even if with lower growth rates and final cell loads. Different rates of BA formation were observed, with tyramine concentrations ranging from 120 to 160 mg/l after 96 h of incubation, and 2-phenylethylamine was produced in lower amounts, usually after reaching the peak of tyramine. FCM confirmed the higher efficacy of R. fruticosus EO that induced cell membrane injury in 93% of the total population. However, complete recovery occurred in the following incubation, demonstrating transient damage. Although further research is required to better investigate this recovery and to assess the suitability of this approach in a real food system, the present study showed the potential antimicrobial activity of plant derivatives, especially R. fruticosus EO, against the tyramine-producing E. faecium FC12.

Screening of Antifungal Activity of Essential Oils in Controlling Biocontamination of Historical Papers in Archives.

The main challenge in controlling the microbiological contamination of historical paper is finding an adequate method that includes the use of cost-effective, harmless, and non-toxic biocides whose effectiveness is maintained over time and without adverse effects on cultural heritage and human health. Therefore, this study demonstrated the possibility of using a non-invasive method of historical paper conservation based on plant essential oils (EOs) application. Evaluation of antimicrobial effects of different EOs (lemongrass, oregano, rosemary, peppermint, and eucalyptus) was conducted against Cladosporium cladosporoides, Aspergillus fumigatus, and Penicillium chrysogenum, which are commonly found on archive papers. Using a mixture of oregano, lemongrass and peppermint in ratio 1:1:1, the lower minimal inhibition concentration (0.78%) and better efficiency during a vapour test at the highest tested distance (5.5 cm) compared with individual EOs was proven. At the final step, this EOs mixture was used in the in situ conservation of historical paper samples obtained from the Archives of Vojvodina. According to the SEM imaging, the applied EOs mixture demonstrates complete efficiency in the inhibition of fungi colonization of archive papers, since fungal growth was not observed on samples, unlike the control samples.

Comparison of the virucidal efficacy of essential oils (cinnamon, clove, and thyme) against hepatitis A virus in suspension and on food-contact surfaces

Essential oils (EOs) have been used for centuries as flavor enhancers in foods, and owing to their antimicrobial properties, they have potential as natural food preservatives. However, their effect on food-borne viruses is unknown. Therefore, in this study, the virucidal effects of three EOs (cinnamon, clove, and thyme) on the infectivity of the hepatitis A virus (HAV) were investigated. Different concentrations of each EO (0.05, 0.1, 0.5, and 1%) were mixed with viral suspensions in accordance with ASTM E1052–11:2011 and incubated for 1 h at room temperature. The EOs exhibited a concentration-dependent effect in the suspension tests, and HAV titers decreased by approximately 1.60 log PFU/mL when treated with EOs at the highest concentration of 1%. The antiviral effect of EOs treated at 1% for 1 h was also evidenced in surface disinfection tests according to the OECD:2013, as approximately 2 log PFU/mL reduction on hard food-contact surfaces (stainless steel and polypropylene) and approximately 2 and 1.4 log PFU/mL reduction on low-density polyethylene and kraft (soft food-contact surfaces), respectively. Moreover, RT-qPCR results revealed that HAV genome copies were negligibly reduced until treated with a high concentration (1%) in suspension and carrier tests. Overall, our findings highlighted the potential of cinnamon, clove, and thyme EOs as natural disinfectants capable of limiting HAV (cross-) contamination conveyed by food-contact surfaces. These findings advance our knowledge of EOs as antimicrobials and their potential in the food sector as alternative natural components to reduce viral contamination and improve food safety.

Inhibition of plant essential oils and their interaction in binary combinations against tyrosinase.

Essential oils (EOs), derived from aromatic plants, exhibit properties beneficial to health, such as anti-inflammatory, anti-oxidative, antidiabetic, and antiaging effects. However, the effect of EOs and their interaction in binary combinations against tyrosinase is not yet known. To evaluate the underlying mechanisms of EOs and their interaction in binary combinations against tyrosinas. We explored to investigate the inhibitory effect of 65 EOs and the interaction among cinnamon, bay, and magnolia officinalis in their binary combinations against tyrosinase. In addition, the main constituents of cinnamon, bay, and magnolia officinalis were analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that the most potent EOs against tyrosinase were cinnamon, bay, and magnolia officinalis with IC50 values of 25.7, 30.8, and 61.9 μg/mL, respectively. Moreover, the inhibitory mechanism and kinetics studies revealed that cinnamon and bay were reversible and competitive-type inhibitors, and magnolia officinalis was a reversible and mixed-type inhibitor. In addition, these results, assessed in mixtures of three binary combinations, indicated that the combination of cinnamon with bay at different dose and at dose ratio had a strong antagonistic effect against tyrosinase. Magnolia officinalis combined with cinnamon or bay experienced both antagonistic and synergistic effect in anti-tyrosinase activity. It is revealed that natural EOs would be promising to be effective anti-tyrosinase agents, and binary combinations of cinnamon, bay, and magnolia officinalis might not have synergistic effects on tyrosinase under certain condition.

Effect of Nanoemulsion Containing Enterocin GR17 and Cinnamaldehyde on Microbiological, Physicochemical and Sensory Properties and Shelf Life of Liquid-Smoked Salmon Fillets.

The spoilage of liquid-smoked salmon represented a serious restriction for shelf life, due to the loss of taste, smell, color and consistency in product quality. The objective of this study was to investigate the feasibility of applying a nanoemulsion delivery system co-encapsulated enterocin Gr17 and essential oils (EOs) to the refrigerated storage of liquid-smoked salmon. The synergistic inhibiting effects of enterocin Gr17 and EOs were evaluated, a nanoemulsion delivery system with the optimal combination was developed, and the evolution of the microbiological, physicochemical, and sensory properties of liquid-smoked salmon fillets were analyzed during a 49-day period of refrigerated storage. The results showed that the combination of enterocin Gr17 and cinnamaldehyde essential oil (CEO) displayed the strongest synergistic inhibiting effect on foodborne pathogens. A nanoemulsion system incorporating enterocin Gr17 and CEO was successfully developed and presented a broad spectrum of activity against most of the tested bacteria. A nanoemulsion system incorporating enterocin Gr17 and CEO (CO-NE) could significantly inhibit the growth of microflora, suppress the accumulation of total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substance (TBARS), and maintain better color, texture, and sensory profiles during smoked salmon storage at 4 °C. Overall, from a microbiological, physicochemical, and sensory point of view, the CO-NE treatment could extend the shelf life to 42 days and maintain the relatively low TVB-N value (≤15.38 mg/100 g), TBARS value (≤2.51 mg MDA/kg), as well as a relatively high sensory score (≥5.83) during the whole storage period. Hence, a nanoemulsion system incorporating enterocin Gr17 and CEO could be a promising bio-preservative technology and alternative to the conventional processes used for improving the safety and quality of chilled liquid-smoked salmon.

Inhibitory potential of some selected essential oils and their main components on the growth and quorum-sensing based pigment production of Serratia marcescens

"In this study the antibacterial potential of ten essential oils (EOs) and their main compounds against the development and quorum sensing (QS) mechanisms of the opportunistic bacterium Serratia marcescens was determined. The growth and QS inhibitory effect was evaluated by paper disc diffusion assay. The effect of EOs and components on QS-regulated prodigiosin biosynthesis was also studied. The results of our study indicated that some of the investigated EOs influenced the development and the QS-based activity of S. marcescens. Oregano and thyme oils showed the most pronounced antibacterial effect and had the strongest anti-QS potential. From the main oil compounds the phenolics, eugenol, carvacrol and thymol, proved to be efficient growth inhibitors. While eugenol and carvacrol had also a strong negative influence on AHL-mediated QS-systems in low concentrations, thymol was not effective in QS inhibition. Keywords: essential oils, quorum-sensing, prodigiosin."

Chemical Composition Determination and Evaluation of the Antimicrobial Activity of Essential Oil from Croton blanchetianus (Euphorbiaceae) against Clinically Relevant Bacteria.

In this study, the chemical composition of the essential oil (EO) extracted from Croton blanchetianus Baill leaves was identified, and antimicrobial and antibiofilm activities against Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli strains were determined. Moreover, the effects of EO in combination with ampicillin and tetracycline were investigated. Thirty-four components, mainly mono-and sesquiterpenes that represented 94.05 % of the chemical composition, were identified in the EO. The EO showed bacteriostatic and bactericidal activities against all strains tested. Furthermore, the EO showed a synergistic effect with ampicillin and tetracycline. EO significantly inhibited biofilm formation and reduced the number of viable cells in biofilms. The EO may be a promising natural product for preventing bacterial biofilm infections.

Can Essential Oils Be a Natural Alternative for the Control of Spodoptera frugiperda? A Review of Toxicity Methods and Their Modes of Action

Spodoptera frugiperda is a major pest of maize crops. The application of synthetic insecticides and the use of Bt maize varieties are the principal strategies used for its control. However, due to the development of pesticide resistance and the negative impact of insecticides on the environment, natural alternatives are constantly being searched for. Accordingly, the objective of this review was to evaluate the use of essential oils (EOs) as natural alternatives for controlling S. frugiperda. This review article covers the composition of EOs, methods used for the evaluation of EO toxicity, EO effects, and their mode of action. Although the EOs of Ocimum basilicum, Piper marginatum, and Lippia alba are the most frequently used, Ageratum conyzoides, P. septuplinervium. O. gratissimum and Siparuna guianensis were shown to be the most effective. As the principal components of these EOs vary, then their mode of action on the pest could be different. The results of our analysis allowed us to evaluate and compare the potential of certain EOs for the control of this insect. In order to obtain comparable results when evaluating the toxicity of EOs on S. frugiperda, it is important that methodological issues are taken into account.

Synergic effects of some plant-derived essential oils and Iranian isolates of entomopathogenic fungus Metarhizium anisopliae Sorokin to control Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae).

The bean weevil, Acanthoscelides obtectus, is one of the most important pests of the common bean, Phaseolus vulgaris. The pest attacks P. vulgaris seeds while they are still in the field. However, the damage continues during storage, where it causes the most significant losses. The present study was conducted to evaluate the insecticidal activity, and synergic effects of three essential oils (EOs) extracted from fennel (Foeniculum vulgare), tarragon (Artemisia dracunculus), and lavender (Lavandula angustifolia), and three isolates from an entomopathogenic fungus (EPF), Metarhizium anisopliae, including IRAN2273C, IRAN2252C, and IRAN1018C against the adults of A. obtectus. The effects of EOs were also evaluated on mycelial growth and conidiation of the fungal isolates. The results showed that all the EOs and the EPF exhibited insecticidal activity against A. obtectus. According to calculated LC50, L. angustifolia (1.2526 µl/l) and F. vulgare (0.9247 µl/l) EOs caused significantly higher mortality than A. dracunculus (3.1980 µl/l) against A. obtectus. The results of the pathogenicity of M. anisopliae isolates revealed that all isolates had insecticidal activity against A. obtectus. The cumulative mortality of insects varied from 59.12% in IRAN1018C to 80.86% in IRAN2273C. According to the compatibility test results, all EOs were compatible with fungal isolates except for A. dracunculus, which was toxic to the IRAN2252C isolate and showed incompatibility. The mortality of A. obtectus adults differed significantly among combined treatments of EOs and M. anisopliae isolates. According to the calculated synergic ratio, combinations of essential oils and fungal isolates had additive or synergistic effects on the mortality of A. obtectus. Based on the present findings, A. obtectus adults were susceptible to fennel, and lavender EOs, and their mortality was amplified when the EOs were combined with M. anisopliae isolates. These results can be helpful for the integrated management of A. obtectus during storage.

New insights into the persistent effect of transient cinnamaldehyde vapor treatment on the growth and aflatoxin synthesis of Aspergillus flavus

The antimicrobial effects of continuous treatment with essential oils (EOs) in both liquid and gaseous phases have been intensively studied. Due to their rapid volatility, the effects of EOs on microorganisms after transient treatment are also worth exploring. In this work, the persistent effects of cinnamaldehyde (CA) vapor on Aspergillus flavus were detected by a series of biochemical analyses. Transcriptome analysis was also conducted to study the gene expression changes between recovered and normal A. flavus. When CA vapor was removed, biochemical analyses showed that the oxidative stress induced by the antimicrobial atmosphere was alleviated, and almost all the damaged functions were restored apart from mitochondrial function. Remarkably, the suppressed aflatoxin production intensified, which was confirmed by the up-regulation of most genes in the aflatoxin synthetic gene cluster, the velvet-related gene FluG and the aflatoxin precursor acetyl-CoA. Transcriptomic analysis also demonstrated significant changes in secondary metabolism, energy metabolism, oxidative stress, and amino acid metabolism in the recovery group. Taken together, these findings provide new insights into the mechanisms underlying the response of A. flavus to CA vapor treatment and will guide the rational application of EOs.

Investigating the antimicrobial activity of essential oils against pathogens isolated from sewage sludge of southern Lebanese villages.

Due to the high load of pathogens in sewage, seeking for effective treatments became a priority. In this regard, testing the sensitivity of microorganisms isolated from sewage against essential oils (EOs) is suggested. In Lebanon, little evidence supports bacteria isolated from sewage reveals a sensitivity to EOs. Due to this fact, the present investigation aims at determining the sensitivity of microbes isolated from sewage sludge to three EOs: lettuce, coconut, and almond. Bacterial isolates were identified by VITEK screening. Yeast was identified by germ tube assay. The chemical components of the oils were identified by gas chromatography - mass spectrometry (GC-MS). Susceptibility of the microbial isolates was assessed by the agar well diffusion assay. Bacteriostatic and bactericidal effects of EOs were detected by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) broth microdilution assay. The activity of EOs on biofilms was detected by antibiofilm screening. The identified microorganisms include Gram-negative isolates (Escherichia coli, Citrobacter freundii, Citrobacter braakii, Leclercia adecarboxylata, and Stenotrophomonas maltophilia), Gram-positive isolates (Enterococcus faecium, Streptococcus intermedius, Staphylococcus aureus, Staphylococcus capitis, and Staphylococcus haemolyticus), and Candida albicans. Thirty oils' chemical components were identified. Among the antibiotics, doxycycline exhibited the best inhibitory effect. The three EOs were effective against bacterial isolates and yeast at concentrations ranging between 3.125% and 50%. They exhibited a bacteriostatic activity. Lettuce and coconut oils were effective against biofilm formation and the three oils were effective on pre-formed biofilms. The results reflected the significant antimicrobial and antibiofilm activities of the oils, thus suggesting their potential antimicrobial applications.

Effects of EOs vs. Antibiotics on E. coli Strains Isolated from Drinking Waters of Grazing Animals in the Upper Molise Region, Italy.

The health and safety of grazing animals was the subject of microbiological monitoring on natural source of drinking waters in the upper Molise region, Italy. Surface water samples, on spring-summer season, were collected and submitted to analyses using sterile membrane filtration, cultural medium, and incubation. The level of environmental microbial contamination (Total viable microbial count, yeasts and fungi) and faecal presence (Total and faecal coliforms, E. coli, and Salmonellae spp.) were carried out. By the selective microbiological screening, twenty-three E. coli strains from drinking waters were isolated and submitted to further studies to evaluate antibiotic resistance by antibiograms vs. three animal and two diffuse human antibiotics. Furthermore, after a fine chemical characterization by GC and GC-MS, three Essential Oils (EOs) of aromatic plants (Timus vulgaris, Melaleuca alternifolia, Cinnamomun verum) aromatograms were performed and results statistically compared. The effects of EOs vs. antibiotics on E. coli strains isolated from drinking waters showed a total absence of microbial resistance. In our experimental conditions, even if some suggestions will be further adopted for better managements of grazing animals, because the health and safety represent a guarantee for both animals and humans.

Sexual competitiveness of sterile Ceratitis capitata males exposed to essential oils from non‐host plant species native to Argentina

AbstractThe sterile insect technique (SIT) is used to control fruit fly pests, such as the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Enhancing sexual competitiveness of mass‐reared sterile males can contribute to making this technique more effective. It has been shown that exposure to volatiles from essential oils (EOs), such as ginger root oil (GRO) and those from host fruits, increases male mating success. We evaluated the effect of EOs from non‐host species native to Argentina, Schinus polygama (Cav.) Cabrera (Anacardiaceae) and Baccharis spartioides (Hook. & Arn.) Remy (Asteraceae), on the sexual competitiveness of sterile C. capitata males. In field cage experiments, sterile males exposed to S. polygama EO increased their mating success. In addition, sterile males exposed to this EO achieved more matings on trees than non‐exposed males, thus suggesting the former are more prone to locate and defend the pheromone‐calling territory. Deprivation of water and/or food significantly reduced males' life span, but exposure to S. polygama EO and GRO did not affect their survival. Schinus polygama EO is composed of mono‐ and sesquiterpenes with behavioral and electroantennographic responses in medflies, indicating that semiochemicals that boost medfly sexual competitiveness combine in this EO.

Citrus essential oil: would it be feasible as antimicrobial in the bioethanol industry?

Essential oils (EOs) extracted from Citrus peels contain 85%-99% volatile components (a mixture of monoterpenes, sesquiterpenes, and their oxygenated derivatives) and 1%-15% non-volatile compounds. Citrus EOs have been long known for their antimicrobial properties, owing to which these EOs have a diverse range of applications. However, no studies have reported the applicability of Citrus EOs for the control of bacterial and yeast contaminants in the bioethanol industry. In this regard, the present review aimed to explore the feasibility of Citrus EOs in this industry. The Web of Science database was searched for reports that described the association of Citrus EOs with the most common microorganisms in the bioethanol industry to evaluate the efficacy of these EOs as antimicrobial agents in this context. The objective of the review was to suggest a novel antimicrobial that could replace sulfuric acid and antibiotics as the commonly used antimicrobial agents in the bioethanol industry. Citrus EOs exhibit antibacterial activity against Lactobacillus, which is the main bacterial genus that contaminates this fermentation process. The present report also confirms the selective action of these EOs on the contaminating yeasts and not/less on ethanol-producing yeast Saccharomyces cerevisiae, however further studies should be conducted to investigate the effects of Citrus EOs in yeast-bacterium co-culture.

Effects of Origanum majorana essential oil and antibiotics on the quality of frozen thawed Beni Arouss buck semen.

This study aims to investigate the effects of Origanum majorana (OM) essential oil (EO) at different concentrations and antibiotics on post-thawed Beni Arouss buck semen quality. Semen collection was performed using artificial vagina from eight Beni Arouss bucks. Ejaculates were pooled, divided into 12 equal aliquots, washed and diluted to 400 × 106 sperm/ml (with 7% of glycerol). Skim milk-based extender was supplemented with different concentrations of OM EO (0%; 0.01%; 0.02%; 0.03%; 0.04% and 0.05%) without antibiotics, marked as (CTR-), (M1-), (M2-), (M3-), (M4-) and (M5-), and with 50 mg of streptomycin and 50,000 IU of penicillin per 100 ml, marked as (CTR+), (M1+), (M2+), (M3+), (M4+) and (M5+), respectively. Aliquots were cooled to 4°C, then frozen in 0.25 ml straws with a programmable freezer and finally stored in liquid nitrogen for 48 h. Thawing was performed at 37°C for 30 s. Motility, live sperm, sperm abnormalities, membrane integrity, lipid peroxidation and bacterial growth were evaluated after thawing. Among the tested extenders, M2+ improved all semen quality parameters. Sperm motility, live sperm and membrane integrity increased significantly, while the number of abnormal sperm and bacterial growth decreased significantly. The toxic effect of OM EO, with and without antibiotics, appeared beyond 0.03%. In conclusion, M2+ is recommended to improve the cryopreservation of Beni Arouss buck semen.

Essential Oils as Potential Tools to Control Listeria Monocytogenes in Foods

Foodborne diseases are indisputable risks to human health, as they are directly affected by the consumption of food and beverages exposed to spoiling and pathogenic microorganisms. A commonly confronted issue by the food industry is the use of synthetic additives to control microbial growth on food products. Alternatively, plant essential oils (EOs) are natural compounds with antimicrobial effects against pathogens in edible and drinkable products. Based on bacteriostatic and bactericidal activities, this review describes the antimicrobial effects of plant EOs on Listeria monocytogenes, also indicating their potential applicability in different food products. Conclusively, it is determined that the Gram-positive bacteria have more susceptibilities to the EOs. In addition, the antibacterial efficacy of the EOs reported in the literature varied according to several parameters, including the seasonal harvest of plants, well-settled methodologies for extraction of EOs, experimental conditions for testing the antibacterial effect on L. monocytogenes, and matrix effects considering several types of foodstuffs. This later represents the main challenge to be addressed in future research aiming at specific applications of EOs in food products.

Comparative Study of Nano-liposome and Nano-niosome for Delivery of Achillea Millefolium Essential Oils: Development, Optimization, Characterization and Their Cytotoxicity Effects on Cancer Cell Lines and Antibacterial Activity.

Nanoencapsulation of essential oils (EOs) in drug delivery systems leads to their capability of improving their solubility, stability, and bioavailability of them. The aim of this study was preparation, optimization, and characterization of nano-liposomes/nano-niosomes containing Achillea millefolium essential oils (A. millefolium EOs) and comparison of their properties. In the experimental study, characteristics of nanoparticles including size, zeta potential, Fourier Transform Infrared Spectroscopy (FTIR), % encapsulation efficiency (EE%) and the release amount of essential oils from nano-liposome or niosome were assessed using different techniques. Then to determine cell viability at different concentrations, the MTT assay was used. Also, the dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of antimicrobial agents. The optimized formulations provided potential advantages, including an appropriate nano-size scale, and a negative charge, and also showed a continuous drug release behavior, which successfully encapsulated essential oil with high entrapment efficiency. In terms of size and release amount, nano-niosome had superiority to nano-liposome with smaller size and also slower release but nano-liposome could encapsulate essential oils in a higher percentage compared to nano-niosome. Also, there was a significant difference between the toxicity of encapsulated EOs and free EOs in terms of viability (P<0.05). In addition, the antimicrobial effect of liposomal and niosomal EO was greater than free EO. In conclusion, the designed nano-based systems were determined as promising lipid-based nano-carriers for essential oil delivery that proffered a novel, high potential therapy for breast cancer and favorable antimicrobial effects.

Chemical composition, antifungal and phytotoxic activities of Cistus ladanifer L. essential oil and hydrolate

The use of synthetic chemical fungicides commonly applied in crop protection has been associated with environmental and human health risks. However, essential oils (EOs) and other bioproducts, such as hydrolates, are gaining more attention as eco-friendly alternative biofungicides. We analysed the chemical composition of essential oil (EO) and hydrolate obtained from hydrodistillation of air-dried plants of Cistus ladanifer L. by GC-MS. To assess their potential application as biofungicides, we evaluated the antifungal activity and phytotoxicity of EO and hydrolate. The oxygenated sesquiterpenes was the dominant group in the EO (28.36%), and the oxygenated monoterpenes in the hydrolate (43.62%). We tested the effect of EO and hydrolate on the mycelial growth of three phytopathogenic fungi (Fusarium oxysporum f.sp. radicis-lycopersici, Rhizoctonia solani and Cryphonectria parasitica) and one oomycete species (Phytophthora cinnamomi). The EO and hydrolate inhibited the mycelial growth of all four fungal species. The potential antifungal effect of the hydrolate was subsequently evaluated in situ with the experimental pathosystem P. cinnamomi - Lupinus luteus. The results showed that the hydrolate application significantly reduced seedling mortality in all three strains of P. cinnamomi tested (MYC-18, CA-9 and CA-4) (ED50 = 165.5 μl/ml, ED50 = 238.1 μl/ml and ED50 = 234.1 μl/ml, respectively). In phytotoxicity tests with Raphanus sativus and L. luteus seeds, the EO and hydrolate showed dose-dependent and species-dependent phytotoxic effects. These results show the high potential the C. ladanifer hydrolate to be used in the production of biofungicides to control phytopathogenic fungi.

Chemical composition, Antibacterial and Antioxidant Activities of the Essential Oil of Lavandula Pedunculata from Khenifra Morocco

Essential oils (EO) extracted from medicinal and aromatic plants (MAP) have proven to be good sources of bioactive compounds with antibacterial and antioxidant properties. This work presents the study of the chemical composition of Essential Oil extracted from Lavandula Pedunculata from the middle atlas of Morocco and its antioxidant and antibacterial power. The EO was obtained by hydrodistillation and analyzed by gas chromatography coupled to mass spectrometry. The antibacterial power of EO was estimated by the disk diffusion method against six bacterial species stemming from the hospital. Antioxidant activity was tested by two methods: measuring the trapping power of DPPH radical and measuring the Ferric Reducing/Antioxidant Potential (FRAP). The chromatographic analysis of Lavandula Pedunculata essential oil allowed the identification of 55 compounds representing 98.9% of the essential oil, of which the major compounds are camphor (44.16%), 1 –epi-cubenol (8.61%), fenchone (7.48%), camphene (6.45%) and α-pinene (4.86%). Antibacterial power tests showed that L. Pedunculata EO effect on all the tested bacteria is lower than that of the most powerful Antibiotic and even powerless on certain strains. The obtained results from antioxidant power tests by both methods proved the antioxidant power of Lavandula Pedunculata EO but was less effective than ascorbic acid. The obtained results indicate that the plant EO’s antibacterial and antioxidant activities are not powerful compared to antibiotics and ascorbic acid respectively, but enough to explain the traditional therapeutic use of the plant.

Effect of Selected Essential Oils Against Zoonoses and their Epidemiological Survey Among Domestic Rodents in Egypt

A cross-sectional seroprevalence survey of certain pathogenic zoonses in domestic rodents from Abou El Noumorus district, Egypt, was conducted. In addition, antimicrobial of selected essential oils (EOs) was performed and the Minimum Inhibitory Concentration (MIC) was measured. The overall prevalence of antibodies against tested organisms was determined. MIC of the tested EOs showed a promising result. This study provides a serological evidence about the occurrence of these bacteria among domestic rodents. This information is helpful for determining strategies for rat zoonotic diseases prevention and control. Also, it highlighted the effect of certain EOs against the isolated zoonotic pathogens.