Laurel Essential Oil Research Articles

Inhibitory Effect of Oregano and Laurel Essential Oils and Their Main Com-ponents on Seed Germination of Some Weed and Crop Species

The essential oils from oregano (Origanum syriacum L.) and laurel (Laurus nobilis L.), and their main components, namely, carvacrol, 1,8-cineole and α-pinene, were tested to determine their inhibitory effects on the seed germinations of three different weeds [redroot amaranth (Amaranthus retroflexus L.), wild licorice (Glycyrrhiza glabra L.), curled dock (Rumex crispus L.) and cutleaf ground-cherry (Physalis angulata L.)] and three crops [(wheat (Triticum aestivum L.), corn (Zea mays L.) and cotton (Gossypium hirsitum L.)]. Gas chromatography/mass spectroscopy (GC-MS) analysis showed that 1,8-cineole and carvacrol were the major components of laurel and oregano essential oils, respectively. An in-vitro bioassay seed germination test showed that oregano essential oil and carvacrol completely inhibited the germination of weeds at all the concentrations ranging from 1 to 5 µl/Petri dish, while seed germination of test weeds significantly decreased with increasing of the concentrations of laurel essential oil and its main components, 1,8-cineol and α-pinene ranging from 5 to 20 µl/Petri dish. Oregano essential oil and carvacrol were totally ineffective on cotton and corn germination (except for the concentration of 5 µl/Petri dish of cavracrol), whereas they had a strong inhibitory activity against wheat seeds. On the other hand, the laurel essential oil and its main component, 1,8-cineole, showed less selective action on test crop species. It could be concluded that volatile oil from O. syriacum and its main component, cavracrol, possessed a strong inhibitory effect on germination of the weeds and was totally selective action on some crops, and could be utilized as bioherbicide for future weed management programmes.

Laurel essential oil: biological activities and application for semolina preservation against the red flour beetle Tribolium castaneum (Tenebrionidae)

ABSTRACT The phytochemical composition of Laurus nobilis essential oil and their anticholinesterase, antioxidant, and insecticidal potential were studied. Also, the oil volatile fraction was compared in semolina at the beginning and after storage periods. For that, a headspace solid-phase-microextraction analysis (HS-SPME) coupled with gas chromatography and mass spectrometry was undertaken. Significant quantitative and qualitative differences of the oil volatile fraction were detected according to storage periods and occupation space ratios. Additionally, anti-acetylcholinesterase activity of L. nobilis oil against T. castaneum adults was evaluated. Results revealed that insecticide activity varied according to storage duration and occupation space. Besides, the oil acts on acetylcholine hydrolysis by inhibiting the activity of acetylcholinesterase. These results highlighted that L. nobilis essential oil may be recommended as an eco-friendly alternative for preserving semolina during storage.

Fractions of laurel essential oil obtained by molecular distillation with greater antioxidant and antimicrobial activities

This study aimed to analyze the chemical composition and the antioxidant and antimicrobial activities of Laurus nobilis L. essential oil (LEO) and its fractions obtained by short-path molecular distillation. According to the chemical composition, it can be said that LEO and its fractions proved to have antioxidant activity sinceboth have a high content of total phenolic content (TPC). Short-path molecular distillation was used to separate essential oil fractions with superiorantioxidant activity. Laurel residue (LR) exhibited the greatest antioxidant activity, with higher values of trolox equivalent antioxidant capacity with ABTS radical cation (TEAC-ABTS) assay and TPC. In addition, LR had the lowest value of IC50-DPPH. For antimicrobial activity, all natural products tested had an effect on all foodborne pathogenic microorganisms. LEO, as well as its fractions, showed antimicrobial, bacteriostatic, or bactericidal activity against Gram-positive and Gram-negative bacteria. The LEO and its fractions obtained by molecular distillation can be used as antimicrobials and as food preservatives to prevent oxidation. Also, consumers considered the addition of LEO or its fractions in food products as positive.

Combined Effect of Chitosan Coating and Laurel Essential Oil (Laurus nobilis) on the Microbiological, Chemical, and Sensory Attributes of Water Buffalo Meat.

The combined effect of chitosan coating (CHI) and laurel essential oil (LEO) on the shelf-life extension of water buffalo meat stored under aerobic packaging conditions at 4 °C was investigated. Microbiological, physicochemical, and sensory attributes were monitored over an 18-day storage period. Microbiological data indicated that the (CHI) coating along with (LEO) was the most efficient among treatments in reducing populations of bacteria by 3.2 log cfu/g on day 6 of storage (p < 0.05). pH values of meat varied between 6.04 and 6.21, while thiobarbituric acid (TBA) values were equal to or less than 2.12 mg malondialdehyde/kg throughout storage. The colour parameter L* and a* values decreased, while b* values increased during storage (p < 0.05). Taste proved to be a more sensitive sensory attribute than odour. Based on sensory and microbiological data, product shelf life was approximately 5–6 days for control samples, 7–8 days for samples treated with (LEO), 12 days for samples treated with (CHI), and 13–14 days for samples treated with (CHI + LEO).

Effect of lavander (Lavandula angustifolia) and laurel (Laurus nobilis) essential oils as anesthesics in rainbow trout (Oncorhynchus mykiss)

In this study, anesthetic effects of lavender ( Lavandula angustofolia ) and laurel ( Laurus nobilis ) essential oils were investigated in rainbow trout ( Oncorhynchus mykiss ). Fish (avarege 10 g) were exposed to different concentrations of essential oils (5, 10, 20, 50, 70, 100, 150, 200, 300, 400, 500 and 600 mg L −1 ). Anesthesia induction and recovery times were evaluated. In addition, histopathological effects of the essential oils in fish tissues were determined after deep anesthesia. As a result of this study, lavender essantial oil at 200 mg L −1 dose and laurel essential oil at 400 mg L −1 dose showed ideal anesthetic effects on rainbow trout. At these concentrations, deep anesthesia (Stage 4) induction times were 258.0 s for lavender and 189.5 s for laurel. Recovery times at these concentrations were 41 s for lavender and 129.5 s for laurel. No histopathological finding in gill, liver and kidney was observed. Consequently, this study was demostrated that lavender and laurel essential oils can be used as effective anesthetic in rainbow trout. • Anesthetic effects of laurel essential oil on rainbow trout determined for the first time in this study. • Laurel essential oil at 400 mg L −1 dose and lavender oil at 200 mg L −1 dose are suitable for anesthesia in rainbow trout. • No histopathological findings were found in gill, liver and kidney of fish exposed to 600 mg L −1 EOs. • This study was demostrated that lavender and laurel essential oils can be used as effective anesthetic in rainbow trout.

Influence of Heating on Thermal Stability of Essential Oils During Storage

Volatile oils are natural products with high antioxidant activity but their chemical composition and antioxidant activities may change due to the thermal storage conditions. In the present study, the changes in antioxidant activity and thermal stability of bay laurel, lemon peel, and orange peel essential oils stored at refrigerator temperature (4°C), room temperature (20°C), and elevated temperature (37°C) for 12 months were examined. In the determination of antiradical activity measured using DPPH method at the beginning of storage, the bay laurel essential oil (82.82%) showed a better inhibition percentage when compared to lemon (32.30%) and orange (46.52%) peel oils. During the storage, a decrease was observed in the antioxidant and antiradical activity values of the oils. The aromatic compositions of volatile oils were determined using GC/MS and the main components of volatile oils were found to be 1,8 Cineolene (50.4%) for bay laurel, d-limonene (80.1%) for lemon peel, and d-limonene (94.6%) for orange peel. At the end of this study, it was found that the change in the compositions of essential oil samples stored in the refrigerator was at a lower level, whereas significant changes were observed in both volatile compositions and antioxidant activity values of the samples stored at elevated temperatures. Moreover, it was also observed that the volatile oils obtained might form natural potential agents that can be used as antioxidant in food products.

Antioxidant and Anti-Atherogenic Activities of Essential Oils from Myrtus communis L. and Laurus nobilis L. in Rat.

Essential oils (EOs) from aromatic and medicinal plants, such as myrtle (Myrtus communis L.) and Laurel (Laurus nobilis L.), are gaining popularity as a potential ingredient in functional foods and nutraceuticals. This study aims to investigate whether the essential oils (EOs) could be effective in weight control, antioxidative and antilipidemic status of rats by affecting microbiota and its enzymes activity and whether changes in intestinal enzyme activity affect the health of rats. The intragastric application of laurel and myrtle EOs to rats for two weeks affects weight loss, reduces glycolytic activity, lipid parameters (cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C)) and atherogenic indicators, leading to cardiovascular protection. Laurel EO can be an excellent candidate for the treatment of drug-induced obesity and related diseases, since it affects lipid metabolism in the liver and inhibits the enzymes responsible for the metabolism of carbohydrates into glucose in the digestive tract, leading to weight loss. In contrast, myrtle EO shows a better antioxidant capacity in most tissues, except kidneys, where it causes a pro-oxidative effect, compared to laurel EO. Myrtle EO increases the permeability and instability of the erythrocyte membrane, resulting in a loss of selectivity for the entry of toxic substances into the cell. On the other hand, myrtle EO leads to intestinal inflammation by reducing the number of probiotic bacteria and increasing Enterobacter.

Biological control of Citrus brown spot pathogen, “Alternaria alternata” by different essential oils

ABSTRACT The antifungal effects of laurel, myrtle and peppermint essential oils and their combinations were investigated in vitro on two strains of Alternaria alternata mycelial growth and in vivo on detached Citrus leaf disease incidence. Myrtle essential oil was rich in α-pinene and 1,8-cineole while peppermint essential oil in menthol and menthone. 1,8-Cineole was the main component of the essential oils from laurel, laurel + myrtle and peppermint + laurel. The combined peppermint and myrtle essential oil was characterized by the predominance of menthol and 1,8-cineole. All tested essential oils, incorporated in potato-dextrose agar, inhibited A. alternata mycelial growth and had a fungistatic effect at concentration 3 mg/mL of medium. A great synergism was detected between peppermint and laurel essential oils against the two strains of A. alternata. The combined laurel and peppermint essential oil reduced mycelial growth rates of inoculated detached leaves at concentration above 1.5 mg/mL.

Bay Laurel (Laurus nobilis L.) Essential Oil as a Food Preservative Source: Chemistry, Quality Control, Activity Assessment, and Applications to Olive Industry Products.

Essential oils (EOs) find application as flavoring agents in the food industry and are also desirable ingredients as they possess preservative properties. The Mediterranean diet involves the use of a lot of herbs and spices and their products (infusions, EOs) as condiments and for the preservation of foods. Application of EOs has the advantage of homogeneous dispersion in comparison with dry leaf use in small pieces or powder. Among them, Laurus nobilis (bay laurel) L. EO is an interesting source of volatiles, such as 1,8-cineole and eugenol, which are known for their preservative properties. Its flavor suits cooked red meat, poultry, and fish, as well as vegetarian dishes, according to Mediterranean recipes. The review is focused on its chemistry, quality control aspects, and recent trends in methods of analysis and activity assessment with a focus on potential antioxidant activity and applications to olive industry products. Findings indicate that this EO is not extensively studied in comparison with those from other Mediterranean plants, such as oregano EO. More work is needed to establish authenticity and activity methods, whereas the interest for using it for the preparation of flavored olive oil or for the aromatization and preservation of table oils must be further encouraged.

The influence of laurel essential oil treatment on the shelf-life and sensory characteristics of fresh-cut apples during storage

Fresh-cut apples provide consumers convenient, fresh, ready-to-eat product. However such products are susceptible to browning and microbiological spoilage which occurs very quickly after processing. Due to their antimicrobial properties, essential oils have a potential stabilizing effect on fresh-cut products, but could have undesirable effects on their color or taste. The aim of this study was to investigate the effect of laurel essential oil (LEO) treatment at different concentrations (25, 75, 125 and 175 mg L-1) on the shelf-life (aerobic mesophilic bacteria count) and physical (soluble dry metter, pH, color, texture) and sensory characteristics of fresh-cut apples during 10 days of storage at 8 °C. Number of aerobic mesophilic bacteria decreased with the increase of LEO concentration and it slightly increased with the increase of storage time. In general, samples treated with 75 mg L-1 LEO had the lowest and samples treated with 175 mg L-1 LEO the highest soluble dry matter, while pH trend was vice versa. Soluble dry matter, pH, and firmness increased during storage. Apples treated with 75 mg L-1 LEO after 10 days of storage showed the least color change. This study showed that LEO can be used to preserve and enrich sensory characteristics of fresh-cut apples, especially at a concentration of 75 mg L-1. Generally, this LEO concentration can be recommended regarding the results of microbiological and sensory analysis as well as results of soluble dry matter, pH, color parameters and firmness.

Impacts of edible coatings enriched with laurel essential oil on the storage life of strawberry ‘Camarosa’ fruits

The current research was carried out to test the effects of edible coatings (EC) enriched with laurel essential oil (EC+LEO) on the storability of strawberry ‘Camarosa’ fruits. Freshly harvested strawberry fruits were randomly separated into three groups and each group was treated with a different treatment, including EC, EC+LEO and control. Fruits were stored at 4.0 ± 1.0 °C and a relative humidity of 90–95% for 15 days. Results suggested that both EC and EC+LEO have positive effects of the quality parameters of strawberry fruits and help to improve the storage duration of the fruits. After 15 days of storage, the average weight loss of the control fruits reached to 12.44%, but was kept at 9.06% and 7.13% at the EC and EC+LEO treated fruits, respectively. Both the EC and EC+LEO treatments were found to have positive impact on the prevention of disease severity and chemical spoilage and lowering respiration rate of the fruits. The loss in the fruit firmness, soluble solids concentration, ascorbic acid content and titratable acidity of the fruits were also found to delay in the coated fruits. The EC+LEO treatment was found to have better performance than the EC treatment. Overall results recommended that the edible coatings enriched with laurel essential oil improve the storability of strawberry fruits and have possibility to be used in postharvest industry.

ANTIMICROBIAL ACTIVITY AND CHEMICAL CHARACTERIZATION OF LAUREL ESSENTIAL OIL

The factors that arouse interest in the study of essential oils as biocidal agents are numerous, such as the fact that they have antibacterial, antifungal, insecticidal, antioxidant, anti-inflammatory and larvicidal properties. The objective of this work was to evaluate the antimicrobial activity, in vitro, of the laurel (Laurus nobilis L) essential oil on the growth of pathogenic bacteria Salmonella enterica serovar Typhimurium ATCC 14028 and Staphylococcus aureus ATCC 25923, at different exposure times, as well as to perform the chemical characterization. Twenty compounds were identified and quantified, representing 96.57% of the total composition. The class of oxygenated monoterpenes represented the majority class of the essential oil, with 1,8-cineol (33.8%) as the substance found in greater quantity, followed by linalool (17.79%). The third constituent in greater quantity was sabinene (12.23%), belonging to the group of monoterpene hydrocarbons. Terpinyl acetate (9.41%) was also considered to be quantitatively representative. Laurel essential oil showed bacteriostatic activity against S. Typhimurium ATCC 14028 and S. aureus ATCC 25923.

Preparation of three-layer flaxseed gum/chitosan/flaxseed gum composite coatings with sustained-release properties and their excellent protective effect on myofibril protein of rainbow trout

Plant essential oils lose their activity due to unstable chemical properties and volatility, and the coating can improve their stability by encapsulating. The three-layer coatings were prepared by tape casting method with flaxseed gum (FG) and chitosan (CS) as film-forming materials, eugenol (EG) and laurel essential oil (LEO) as preservatives. The composite coatings were characterized, and their physicochemical properties, release properties, antibacterial and antioxidant properties were determined. Meanwhile, the protective effect of the composite coatings on rainbow trout fillets myofibril protein was studied. The mechanical properties of the FG/CS/FG coatings are better than FG coating. The release of EG and LEO from the coatings are followed simple diffusion mechanism. After added essential oils, the antibacterial and antioxidant properties of the composite coatings are significantly enhanced. In the preservation process of the rainbow trout fillets, the composite coatings can reduce the carbonyl content, increase the sulfhydryl content and Ca2+-ATPase activity. The β-sheet content is 6.09%–15.63% higher than that of control, indicating the coatings are helpful to maintain the order of myofibril protein. The composite coatings slowed down the decrease of antioxidant enzyme activity, thus delay the protein oxidation. Because of long-term antibacterial and antioxidant properties, the composite coatings have potential value in food preservation or food packaging materials.

Use composite coating of chitosan-chia seed gum enriched with microliposomes of Bay laurel essential oil to increase the shelf life of quail fillets.

In this study, the effect of composite chitosan‐chia seed coating (CH‐CG) with Bay laurel (Laurus nobilis) essential oil (BE) in two forms including free and nanocapsulated on the shelf life of quail fillets during the 16‐day refrigeration (4 ± 1℃) period was investigated. For this purpose, first, BE was extracted by Clevenger apparatus. Then, nanoliposomes BE were produced, and the properties of BE and nanoliposomes BE were investigated. In order to investigate the shelf life of quail, 6 treatments were produced including 1: control (C), 2: CH‐CG, CH‐CG+BE at 800 ppm, 3: CH‐CG+BE at 1600 ppm, 4: CH‐CG+nano BE at 800 ppm, 5: CH‐CG+nano BE at 1600 ppm, and periodically chemical parameters (peroxide value, free fatty acid, total volatile basic nitrogen, texture firmness, and chewing ability) and microbial (total viable bacteria (TVC) and psychrotrophic bacteria), and the effect of different treatments on control in Escherichia coli and Staphylococcus aureus inoculated populations in quail was also investigated. The BE had high antioxidant and antimicrobial properties. The particle size and microencapsulation efficiency of BE nanoliposome were 98.3 nm and 75.95%, respectively. The results of chemical and microbial analysis showed that in general, the coating with essential oil slowed down the increasing trend of oxidation and microbial indices compared to the control treatment and nanocapsulation of essential oil has increased its antimicrobial and antioxidant properties (p < .05). At the end of storage period, in all tests, treatments of 3, 4, and 5 had the allowed microbial and chemical range and they also inhibited the growth of these bacteria (p < .05). Overall, considering the higher sensory score of treatment 4 and economic efficiency, it seems that this treatment can be used as a natural preservative in the meat industry.

Prevention of Saprolegniasis in rainbow trout (Oncorhynchus mykiss) eggs using oregano (Origanum onites) and laurel (Laurus nobilis) essential oils

The present study investigated the antifungal effects of essential oils of oregano (Origanum onites) and laurel (Laurus nobilis) on Saprolegniasis, a disease that occurs in rainbow trout eggs during the incubation period. Oregano and laurel were ground after drying, and essential oils were obtained by water distillation method using a Clevenger apparatus. The essential oils were added to potato dextrose agar (PDA) at the rates of 1-1000ppm, and the minimum inhibitory concentration (MIC) was determined as 250ppm whereas the minimum lethal concentration (MLC) was determined to be 500ppm for both plants. In the in vivo trials, fertilized eggs were treated with predetermined doses either by bathing during water hardening and incubation period or only during incubation period, and death rates were monitored during embryological development. The best larvae hatching rate was determined in 500ppm oregano and 500ppm laurel groups treated during water hardening plus daily as 82.11% and 79.87%, respectively. According to the results, it was determined that oregano and laurel essential oils exhibited better results in all doses compared with the negative control group, and 500ppm dose had a better effect than the positive control group treated with formalin.

The effects of essential oils on inactivation of Listeria monocytogenes in rainbow trout cooked with sous‐vide

This study investigated the combined effect of four different natural antimicrobial essential oil (Rosemary, Coriander, Basil and Laurel) and two different cooking temperatures (50℃ and 55℃) on inactivating of Listeria monocytogenes in rainbow trout. The products prepared with this technology were stored at +4℃ for 36 days and the number of L. monocytogenes was determined. As a result of this study, laurel essential oil was found to be effective on L. monocytogenes invitro whereas coriander essential oil was found to be effective on L. monocytogenes in sous-vide applied trout. In addition, coriander essential oil addition (2 times more than the minimum inhibition concentration value) and 7 min sous-vide application in 55℃ was effective for the inhibition of L. monocytogenes in sous-vide applied trouts. Consequently, the findings indicated that the use of coriander essential oil in sous-vide trout fillets was effective to ensure of L. monocytogenes control. Practical applications Sous-vide technology is a long-term cooking method in vacuum-packed food at low temperatures. Thanks to this application, since the products are cooked in vacuum packaging, the unique aroma and nutritional components of the foods are not lost. This technology offers products with high nutritional value, quality, and high shelf life. Although it is more advantageous than traditional cooking methods, if the applied temperature is low and the time is insufficient, pathogenic microorganisms develop and pose a threat to health. For this reason, the temperature-time parameters and the use of antimicrobials used in cooking are of great importance. In this research, it was determined that the development of Listeria monocytogenes in seafood was prevented by using essential oils with sous-vide technology.

Antibiofilm and Antifungal Activities of Laurelia sempervirens (Chilean laurel) Essential Oil

Background: Laurelia sempervirens, better known as Chilean laurel, is endemic to Chile. For many years, the leaves and branches of this plant have been popularly used as medicinal agents. However, its antifungal properties and antibiofilm activity against bacterial strains have not been studied. Objectives: To determine antibiofilm and antimicrobial properties of Chilean laurel essential oil on human pathogenic strains. Methods: The antifungal and antibacterial activities of Chilean laurel essential oil were evaluated through the agar diffusion method, and its minimum inhibitory concentration was determined using the standard microdilution method. Antibiofilm activity was examined based on the formation and disruption of bacterial biofilms and evidenced by the crystal violet technique. Results: The results showed important antimicrobial activity against human pathogenic yeast strains, and the minimum inhibitory concentration of Chilean laurel essential oil was 64 µg mL-1 against Candida albicans. The essential oil also showed an important inhibitory effect against the formation of biofilms produced by Staphylococcus aureus, since it inhibited the formation of biofilms by over 50% at the concentration of 64 µg mL-1. With increasing the essential oil’s concentration to 128 µg mL-1, its antibiofilm activity increased by 60%. Conclusions: These results approve the domestic use of Chilean laurel essential oil as an antimicrobial agent and provide knowledge about the antibiofilm and antifungal properties of L. sempervirens.

Antimicrobial effect of laurel essential oil nanoemulsion on food-borne pathogens and fish spoilage bacteria

This research aimed to apply nanotechnology for nanoformulation of Laurus nobilis essential oil (EO) by ultrasonic emulsification method and characterization of nano-form: particle size, viscosity, polydispersity index, thermodynamic stability, and surface tension. The antimicrobial activity of laurel EO nanoemulsion (LEON) and laurel EO was also investigated against a panel of ten food-borne pathogens and fish spoilage bacteria. The GC–MS analysis of EO revealed that 1,8-Cineole was the main volatile compound. According to disc-diffusion results, LEON was more effective against Gram-positive pathogen bacteria of Staphylococcus aureus and Enterococcus faecalis than EO. Laurel oil demonstrated a higher inhibitory effect against fish spoilage bacteria (6.19 to 18.5 mm). The MICs values of LEON and laurel EO ranged from 6.25 to >25 mg/mL and from 1.56 to >25 mg/mL, respectively. Nanoemulsion and oil exhibited the best bactericidal activity against Pseudomonas luteola. Therefore, LEON can be developed as a natural antimicrobial agent in food industry.

Getting essential oil mixtures by different methods and determination of their compositions

Objective: The aim of the study is to determine the enhancement of the essential oil potential and find a more effective method with fewer substances.Materials and Methods: For this purpose, Laurel and fennel essential oils obtained by the method of hydrodistillation in clevenger and their mixtures obtained by 2 different methods (Mix 1: separately obtained and mixed in appropriate proportions and Mix 2: obtained by placing together in the same glass flask) analyzed by Gc/Ms.Results: When the main components of the Mix-1 mixture are examined, the main components of R3/4D1/4, R1/2D1/2 and R1/4D3/4 combinations are trans-anethhole (54.53%, 32.47% and 17.46%, respectively) and 1.8- cineol (18.16%, 33.11% and 39.37%, respectively). In the second method (Mix-2), the main components of essential oils were examined. The main components of R3/4D1/4, R1/2D1/2 and R1/4D3/4 were trans-anethhol (64.83%, 46.23% and 24.93%, respectively) and 1,8-cineol (11.47%, respectively, respectively). 23.97% and 37.67%).Conclusion: As a result, it is clear that with essential oil blends, the components do not differ, while the proportions of the components do.

In vitro acaricidal activity of essential oil and crude extracts of Laurus nobilis, (Lauraceae) grown in Tunisia, against arthropod ectoparasites of livestock and poultry: Hyalomma scupense and Dermanyssus gallinae

The current study assayed the toxicity of Laurus nobilis essential oil and crude extracts obtained using solvents of increasing polarity (cyclohexane, acetone and ethanol), on two ectoparasites of veterinary importance, i.e., Hyalomma scupense and Dermanyssus gallinae.The major components detected in bay laurel essential oil were dominated by 1.8-cineole (46.56 %), α-terpinenyl acetate (13.99 %), sabinene (7.69), α-pinene (5.75), linalool (5.50), methyleugenol (5.36 %) and β-pinene (3.97). The highest total phenolic and flavonoids contents were present in the ethalonic extract of L. nobilis leaves at an amount of 152.88 mg gallic acid equivalents per gram of dry weight (GAE/g DW) and 21.77 mg quercetin equivalent per gram of dry weight (QE/g DW), respectively.In vitro acaricidal effects of essensial oil and crude extract of L. nobilis against H. scupense were ascertained by adult immersion test of engorged females (AIT) and larval packet test (LPT) compared with a reference drug amitraz.The essential oil exhibited strong acaricidal activity against tick engorged female and inhibition of hatching eggs. After 24 h of exposure, at the highest tested concentration (100 mg/mL) essential oil induced 90.67 % mortality of H. scupense larvae (LC50 = 10.69 mg/mL). Otherwise, essential oil exhibited high acaricidal activity compared to extracts, and among the extract, the ethanolic extract revealed the highest acaricidal efficacy (81.27 % female mortality).Results from mite contact toxicity showed that essential oil and extracts from L. nobilis were toxic to D. gallinae. Bay essential oil was both more toxic to mites, and faster in exerting this toxicity than other tested crude extracts. L. nobilis essential oil concentration leaded to enhance mortality of D. gallinae reaching the highest (100 %) mortality at 12 h with a concentration of 320 mg/mL. While, ethanolic extract acheived this rate after 24 h of exposure at same concentration. Cyclohexanic extract showed weak acaricidal activity.