Inhibitory Effect Of Essential Oils Research Articles

Inhibitory Effect of Essential Oils Obtained from Five Algerian Plants against Pseudomonas aeruginosa, Including Carbapenem-Resistant Strains

Inhibitory Effect of Essential Oils Obtained from Five Algerian Plants against Pseudomonas aeruginosa, Including Carbapenem-Resistant Strains

Inhibitory Effect of Essential Oil from Rond Left Mint (Mentha Rotundifolia) on the Corrosion of C35 Mild Steel in an Acidic Environment

Inhibitory Effect of Essential Oil from Rond Left Mint (Mentha Rotundifolia) on the Corrosion of C35 Mild Steel in an Acidic Environment

Assessing enzymatic inhibitory effects of essential oil from Distichochlamys orlowii K. Larsen & M.F. Newman rhizomes

Distichochlamys orlowii, belonging to the Zingiberaceae family, is an endemic species in Vietnam. In the present study, the chemical composition of essential oil (EO) from D. orlowii rhizomes and its inhibitory activities against α-amylase, α-glucosidase, and tyrosinase were investigated. The gas chromatography – mass spectrometry results demonstrated the presence of four major constituents in the EO, including (E)-citral (37.65%), (Z)-citral (22.13%), geranyl acetate (17.73%), and geraniol (5.90%). In the enzymatic inhibition assays, the EO showed a potent α-amylase inhibitory activity (IC50 = 81.86 ± 0.95 μg/ml) but had no inhibition of α-glucosidase. With respect to the tyrosinase inhibition test, the EO exerted a weak inhibitory activity.

Efficacy and Potential Mechanism of Essential Oils of Three Labiatae Plants against the Pathogenic Fungi of Root Rot Disease in Atractylodes chinensis

Atractylodes chinensis has a high medicinal value and is widely cultivated. However, root rot disease seriously affects the yield and quality of A. chinensis. To develop green and safe pesticides, the inhibitory effect of essential oils (EOs) of three Labiatae plants on the pathogenic fungi that causes root rot disease in Atractylodes chinensis was investigated. The results showed that the Origanum vulgare EO and Thymus mongolicus EO exhibited strong inhibitory effects on Fusarium oxysporum, Fusarium solani, and Fusarium redolens, with 100% inhibition rate. The low MIC values of EOs and their main components against the three pathogenic fungi indicated that all of them showed strong fungicidal effects. The MIC values of O. vulgare EO against F. oxysporum, F. solani, and F. redolens were 2.60 mg/mL, 3.13 mg/mL, and 1.56 mg/mL, respectively. Analyses using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the O. vulgare EO severely damaged the cell wall and cell membrane of mycelial cells. The O. vulgare EO increased cell permeability, leading to a large leakage of cell contents (DNA and proteins). In addition, O. vulgare EO inhibited F. oxysporum by inducing ROS production and reducing the amount of intracellular GSH, leading to a large accumulation of ROS. This study showed that plant EOs have excellent fungicidal activity and can be used as novel natural and environmentally friendly pesticides for the control of root rot in A. chinensis.

Characterization and Inhibitory Effects of Essential Oil and Nanoemulsion from Ocotea indecora (Shott) Mez in Aspergillus Species.

The Aspergillus genus, the etiological agent of aspergillosis, is an important food contaminant and mycotoxin producer. Plant extracts and essential oils are a source of bioactive substances with antimicrobial potential that can be used instead of synthetic food preservatives. Species from the Lauraceae family and the Ocotea genus have been used as traditional medicinal herbs. Their essential oils can be nanoemulsified to enhance their stability and bioavailability and increase their use. Therefore, this study sought to prepare and characterize both nanoemulsion and essential oil from the Ocotea indecora's leaves, a native and endemic species from the Mata Atlântica forest in Brazil, and evaluate the activity against Aspergillus flavus RC 2054, Aspergillus parasiticus NRRL 2999, and Aspergillus westerdjikiae NRRL 3174. The products were added to Sabouraud Dextrose Agar at concentrations of 256, 512, 1024, 2048, and 4096 µg/mL. The strains were inoculated and incubated for up to 96 h with two daily measurements. The results did not show fungicidal activity under these conditions. A fungistatic effect, however, was observed. The nanoemulsion decreased the fungistatic concentration of the essential oil more than ten times, mainly in A. westerdjikiae. There were no significant changes in aflatoxin production.

Effect of Eugenol, Vanillin, and β-Resorcylic Acid on Foodborne Pathogen Survival in Marinated Camel Meat

The combined inhibitory effect of essential oils (EOs) with meat-based marinades has not been fully studied. Therefore, the present study aimed to gauge the effect of a yogurt-based marinade when individually combined with three EOs, namely eugenol (EU), vanillin (VA), or β-resorcylic acid (BR) on camel meat cubes inoculated with Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7 during storage. Fresh camel meat cubes of 10 g were inoculated with bacteria and dipped in the mixture of marinade and EO. Overall, the study had six EO treatments (EU 0.5%, EU 1%, VA 0.5%, VA 1%, BR 0.5%, and BR 1%) and two controls (meat without marinade and marinated meat). Treated meat cubes were stored at 4°C or 10°C for 1, 4, and 7 d. Adding only marinade to the camel meat at 10°C decreased the pathogens by 0.8–2.4 log CFU/g. At 10°C, BR decreased L. monocytogenes, E. coli O157:H7, and Salmonella spp. by 2.0, 1.5, and 1.3 log CFU/g, while EU caused a decrease (p < 0.05) of 1.9, 1.2, and 0.9 log CFU/g, respectively. Similarly, VA caused a reduction in these microorganisms of 1.3, 1.1, and 1.0 log CFU/g, respectively (p < 0.05). The combination of marinade and EO resulted in a decrease of the pathogens ranging from 0.9–1.4 and 2.8–3.7 log CFU/g at 4 and 10°C, respectively. The antimicrobial efficacy of EO alone or when combined with marinade was higher at 10°C than at 4°C with all three pathogens at both 0.5% and 1%. Overall, EOs were found to enhance the microbial safety of camel meat. In addition, they are antimicrobials that occur naturally, require a minimum investment, and may prove to be a great asset for marinated camel meat producers.

Inhibitory effect of essential oils from native Atlantic Forest plants on the growth of Escherichia coli and Bacillus thuringiensis

Brazil is a country rich in biodiversity, with the largest plant genetic diversity in the world; Brazilian medicinal plants are considered promising, but there is little knowledge about them from any point of view. Considering the increase in the number of microorganisms resistant to antimicrobial agents available in the market, the need and relevance of studies to find new compounds with antimicrobial activity has arisen. Objective: The present study aimed to evaluate the inhibitory effect of essential oils from Pimenta pseudocaryophyllus and Piper species native to the Atlantic Forest on Gram-negative (Escherichia coli) and Gram-positive (Bacillus thuringiensis) bacteria. Material and Methods: The essential oils were extracted from dried leaves of native plant species by the hydrodistillation method using a graduated Clevenger apparatus with 1 liter of distilled water for 2.5 hours. For the evaluation of the inhibitory effect of the essential oils, the pure oil and the agar diffusion technique were used. Results: The essential oils of the species of the genus Piper did not show promissive results. However, the volatile portion extracted from Pimenta pseudocaryophyllus has shown positive results against the tested bacterial cells. Conclusion: The essential oils from Piper species have no inhibitory effect on Gram-negative bacteria (E. coli), showing antimicrobial activity only on Gram-positive bacteria (B. thuringiensis). On the other hand, the species P. pseudocaryophyllus has a potential antimicrobial action on both bacteria E. coli and B. thuringiensis.

Inhibitory Effect of Some Plant Essential Oils against Corn Stalk Rot and Ear Rot

Yield losses are experienced in corn fields due to stalk and ear rot disease. The fungicides used against the disease can not show the desired effect and the problem of resistance arises over time. For this reason, it is necessary to develop new strategies in the control against the disease. In this study, it was aim to determine the inhibitory effects of essential oils of rosemary, black cumin, cumin and sandalwood, and ginger against Fusarium verticillioides and Fusarium pseudograminearum under in vitro conditions. The essential oils were applied in doses of 0.25, 0.5, 1, 2 and 4 µl mL-1. PDA medium free of essential oils was used as negative control and PDA medium containing commercial fungicide (80 g l-1 Triticonazole, 40 g l-1 Pyraclostrobin-BASF company) was used as positive control. The experiment was carried out in a randomized plot design with three replications. In addition, chemical content analysis of essential oils was determined by GC-MS method. As a result of the study, as the dose of rosemary, black cumin, sandalwood and ginger essential oils increased, their inhibitory effects against both pathogens increased, and these effects were found close to each other. While the highest inhibitory effect against F. verticillioides and F. pseudograminearum was detected in the positive control treatment of cumin essential oil, 82.1% and 78.9%, respectively, this effect was found to be 74.6% and 68.3% in 4 µl mL-1 dose, respectively. However, more detailed studies should be carried out with these essential oils under field conditions.

Phytochemical Profiling, Antioxidant, Antimicrobial and Cholinesterase Inhibitory Effects of Essential Oils Isolated from the Leaves of Artemisia scoparia and Artemisia absinthium.

The current studies were focused on the phytochemical profiling of two local wild Artemisia species, Artemisia scoparia and Artemisia absinthium leaves’ essential oils, extracted via the hydro distillation method along with evaluation of their antioxidant as well as antimicrobial effects. The constituents of EOs were identified using a combined gas chromatography-mass spectrometric (GC-MS) technique. A total of 25 compounds in A. scoparia essential oil (EOAS) were identified, and 14 compounds with percentage abundance of >1% were tabulated, the major being tocopherol derivatives (47.55%). A total of nine compounds in Artemisia absinthium essential oil (EOAA) were enlisted (% age > 1%), the majority being oleic acid derivatives (41.45%). Strong antioxidant effects were pronounced by the EOAS in DPPH (IC50 = 285 ± 0.82 µg/mL) and in ABTS (IC50 = 295 ± 0.32 µg/mL) free radical scavenging assays. Both the EOs remained potent in inhibiting the growth of bacterial species; Escherichia coli (55–70%) and Shigella flexneri (60–75%) however remained moderately effective against Bacillus subtilis as well as Staphylococcus aureus. Both EOAS and EOAA strongly inhibited the growth of the tested fungal species, especially Aspergillus species (up to 70%). The oils showed anti-cholinesterase potential by inhibiting both Acetylcholinesterase (AChE; IC50 = 30 ± 0.04 µg/mL (EOAS), 32 ± 0.05 µg/mL (EOAA) and Butyrylcholinesterase (BChE; IC50 = 34 ± 0.07 µg/mL (EOAS), 36 ± 0.03 µg/mL (EOAA). In conclusion, the essential oils of A. scoparia and A. absinthium are promising antioxidant, antimicrobial and anticholinergic agents with a different phytochemical composition herein reported for the first time.

Inhibitory Effect of Essential Oil From Fructus of Alpinia zerumbet on Endothelial-to-Mesenchymal Transformation Induced by TGF-β1 and Downregulation of KLF4.

Essential oil from fructus of Alpinia zerumbet (EOFAZ) protects vascular endothelial cell (VEC) injury. Stimulation and injury factors can induce phenotypic changes in VECs and the occurrence of endothelial-mesenchymal transformation (EndMT), accelerating the occurrence and development of cardiovascular diseases. We investigated the role of EOFAZ in EndMT induced by transforming growth factor-β1 (TGF-β1). All experiments were performed using human umbilical vein endothelial cells (HUVECs). HUVECs were preincubated with EOFAZ for 2 hours and then coincubated with TGF-β1 for 72 hours. Krüpple-like factor 4 (KLF4) was inhibited by small interfering RNA or overexpressed by adenovirus infection. Wound healing, transwell, and angiogenesis assays were used to evaluate the migration ability of HUVECs. Quantitative RT-PCR and Western blotting were used for mRNA and protein expression analyses, respectively. Immunofluorescence staining was used to detect expression of related markers. A coimmunoprecipitation assay verified the interaction between KLF4 and acetylated histone H3. TGF-β1 contributed to EndMT in HUVECs in a time-dependent manner, mainly manifested as an increase in cell migration ability and changes in the expression of EndMT-related mRNAs and proteins. EOFAZ could inhibit EndMT induced by TGF-β1. The results after transfection with siKLF4 were similar to those of EOFAZ treatment. After EOFAZ treatment, the expression of KLF4 and acetylated histone H3 decreased, and protein interactions between them decreased, while expression of the Notch/Snail signal axis decreased. EOFAZ can attenuate endothelial injuries and suppress EndMT in HUVECs under TGF-β1 stimulation conditions because it may downregulate KLF4, decrease histone H3 acetylation, and inhibit the transduction of the Notch/Snail signaling axis.

Antioxidant Potential and Inhibitory Effect of Essential Oil from the Aerial Parts of Origanum vulgare L. Against Salmonella Poultry in Morocco

Origanum vulgare L. is an aromatic plant well-known in traditional medicine and widely applied as a food additive due to its great antimicrobial potential. This study aims to investigate the chemical composition of the essential oil (EO) of O. vulgare L. using gas chromatography/mass spectroscopy (GC/MS) and evaluate their antioxidant and antibacterial activities against three strains of Salmonella from avian origin. The O. vulgare L. EO was extracted by hydrodistillation using the Clevenger apparatus and the different chemical compounds were identified using GC/MS. The antimicrobial activity was evaluated using the aromatogram method on agar and microdilution assay in 96-plates, also the antioxidant activity was carried out using four different tests: DPPH, ABTS•+, reducing power, and phosphomolybdate ammonium. Results of chemical composition showed that Carvacrol was the EO’s major compound with a yield of 50.2%. Through DPPH and ABTS•+, the antioxidant activity of the EO showed an IC50 of 5.75 ± 0.11 and 7.35 ± 0.30 mg/mL, respectively. The reducing power and the molybdate assay of EO presented an EC50 of 280.32 ± 8.63 and 275.37 ± 2.79 µg/ mL, respectively. The antibacterial activity revealed that the three strains of Salmonella exhibited a sensitivity with variable diameters ranging between 30 and 40 mm, the MIC values ranging from 12.5 to 50.0 µg/mL, and the MBC which varies between 100 and 200 µg/mL. The obtained results showed that the O. vulgare L. can be used to fight against multiresistant bacteria and can be a source of bioactive molecules given its antioxidant properties.

Anti-Diabetes, Anti-Gout, and Anti-Leukemia Properties of Essential Oils from Natural Spices Clausena indica, Zanthoxylum rhetsa, and Michelia tonkinensis.

Essential oils (EOs) of Clausena indica fruits, Zanthoxylum rhetsa fruits, and Michelia tonkinensis seeds were analyzed for their phytochemical profiles and biological activities, including anti-diabetes, anti-gout, and anti-leukemia properties. Sixty-six volatile compounds were identified by gas chromatography–mass spectrometry (GC–MS), in which, myristicin (68.3%), limonene (44.2%), and linalool (49.3%) were the most prominent components of EOs extracted from C. indica, Z. rhetsa, and M. tonkinensis, respectively. In addition, only EOs from C. indica inhibited the activities of all tested enzymes comprising α-amylase (IC50 = 7.73 mg/mL), α-glucosidase (IC50 = 0.84 mg/mL), and xanthine oxidase (IC50 = 0.88 mg/mL), which are related to type 2 diabetes and gout. Remarkably, all EOs from C. indica, Z. rhetsa (IC50 = 0.73 mg/mL), and M. tonkinensis (IC50 = 1.46 mg/mL) showed a stronger anti-α-glucosidase ability than acarbose (IC50 = 2.69 mg/mL), a known anti-diabetic agent. Moreover, the growth of leukemia cell Meg-01 was significantly suppressed by all EOs, of which, the IC50 values were recorded as 0.32, 0.64, and 0.31 mg/mL for EOs from C. indica, Z. rhetsa, and M. tonkinensis, respectively. As it stands, this is the first report about the inhibitory effects of EOs from C. indica and Z. rhetsa fruits, and M. tonkinensis seeds on the human leukemia cell line Meg-01 and key enzymes linked to diabetes and gout. In conclusion, the present study suggests that EOs from these natural spices may be promising candidates for pharmaceutical industries to develop nature-based drugs to treat diabetes mellitus or gout, as well as malignant hematological diseases such as leukemia.

Potential application of essential oil of Lavandulastoechas in poultry meat during refrigerated storage

The inhibitory effects of essential oil (EO) on bacteria development give them an important role in the fields of the food industry as an additive in food packaging. This study was aimed to identify the effect of Lavandula stoechas EO at different concentrations on chicken fillets quality during refrigerated storage. Antimicrobial and antioxidant activities showed that EO extracted has an important antibacterial activity and antiradical potential. In chicken fillets, the lavender EO (100 and 200 ppm) reduced their oxidation and microbial proliferation during refrigerated storage and with no cytotoxicity effect towards murine macrophage cells. During the storage period, the values of pH, dry matter, acidity and cooking loss of treated fillets were lower than that of the control. The statistical analyses proved greatly significant variations of color between the control and the treated by LEO, during storage. The sensory analysis selected an improvement effect in the organoleptic quality of the chicken meat when it was supplemented by 100 ppm of LEO. The statistical analysis of the microbiological characteristics clearly discriminated the control and those treated with LEO (p&lt;0.05). The effectiveness of LEO was proved by its incorporation as a natural food preservative and the improvement of the shelf life of poultry meat products by about 3 days.

GC characterization and erectogenic enzyme inhibitory effect of essential oils from tangerine and lemon peels: A comparative study

AbstractThis study comparatively evaluated inhibitory effect of essential oils (EOs) from tangerine and lemon peels on some enzymes [angiotensin‐converting enzyme (ACE), acetylcholinesterase (AChE), arginase, monoamine oxidase (MAO), phosphodiesterase‐5 (PDE‐5), adenosine deaminase (ADA) and 5’‐nucleotidase] related to erectile dysfunction (ED), as well as thiobarbituric acid reactive species (TBARs) level in isolated Wistar albino rats’ penile homogenate. In addition, the chemical compositions of these EOs were characterized via gas chromatography coupled with flame ionization detector (GC‐FID). The result revealed that the studied EOs were able to inhibit these erectogenic enzymes and TBARs level in a dose‐dependent manner. The EOs were found to be rich in monoterpenes hydrocarbon. However, the major constituent in both oils was D‐limonene, 45.48% and 34.99% abundance in lemon and tangerine EOs, respectively. Other phytoconstituents detected in substantial amounts include the following: 4‐Vinyl‐2‐methoxyphenol (5.42% and 2.97%), N‐methyl‐D3‐Aziridine (6.58% and 10.01%) and Xanthotoxin (12.055 and 18.7%) for lemon and tangerine EOs, respectively. It is suggestive that these EOs owe their exceptional inhibitory capacities to the availability of these phytochemicals. Hence, their ability to inhibit ACE, AChE, arginase, MAO, PDE‐5, ADA and 5’‐nucleotidase activities, and TBARs level could be the possible mechanism by which the studied EOs exert their therapeutic potentials in the management of ED.

Antifungal Activity of Essential Oil From Zanthoxylum armatum DC. on Aspergillus flavus and Aflatoxins in Stored Platycladi Semen.

The major objective of this study was to evaluate the inhibitory effect of essential oil (EO) from Zanthoxylum armatum DC. on Aspergillus flavus. The chemical composition of the EO was identified by gas chromatography–mass spectrometer. The minimum inhibitory concentration (MIC) of EO was investigated by liquid fermentation. The morphology, colony number, and aflatoxin content of A. flavus in platycladi semen were investigated by stereomicroscopy, scanning electron microscopy, plate counting, and high-performance liquid chromatography. The results indicated that the MIC of EO was 0.8 μL⋅mL–1, and the main components were β-phellandrene (7.53%), D-limonene (13.24%), linalool (41.73%), terpinen-4-ol (5.33%), and trans-nerolidol (6.30%). After the EO fumigated the platycladi semen, the growth of A. flavus slowed, and the mycelium shrank considerably. The number of colonies after EO treatment at room temperature and cold storage was significantly reduced, the inhibition effect was better under cold storage, and the aflatoxin B1 content did not exceed the standard within 100 days. Therefore, this study demonstrated the good potential of A. flavus growth inhibition during the storage of platycladi semen.

Microwave-assisted solvent-free extraction of essential oil from Coleus aromaticus: anti-phytopathogenic potential for fruit post-harvesting.

This work evaluates the fungicidal effect of essential oil from Coleus aromaticus (C. aromaticus) by solvent-free microwave-assisted extraction with a yield of 0.54%. Fourier-transform infrared spectroscopy was utilised to identify the functional groups, which were O-H, C-O, C-H, and C=C. Gas chromatography-mass spectrometry analysis was performed to determine the primary essential oil components, namely, thymol (92.62%), thymoquinone (2.64%), creosol (1.77%), linalool (1.68%), p-Cymene-2,5-diol (0.73%), and p-Cymene (0.56%). The inhibitory effect of essential oil extracted from C. aromaticus against the isolated fungi, Aspergillus niger from mango, was investigated. The mycelial growth inhibition of the extracted essential oil by the poisoned food test and disc diffusion assay showed the reduction at 79.63 ± 1.7 and 70.45 ± 6.54%, respectively. In vivo experiment was conducted with artificially wounded and unwounded mangoes, applying the extracted essential oil to the wounded mangoes inoculated with A. niger that could decrease the disease incidence from 100 to 58.33 ± 14.43%. Meanwhile, the treatment of the extracted essential oil did not affect the quality of the mango and it also shows improvement in weight loss reduction of the mango in comparison to the chemical fungicide and untreated mango. Hence, essential oil from C. aromaticus by solvent-free microwave-assisted extraction could be used as an effective control for the fruit spoilage and potential source of fruit preservative.

Inhibitory Effects of Essential Oils of Cinnamon zeylanicum and Myristica fragrans against Brucella abortus 544 Inoculated in Fresh Baladi Cheese

Background: Essential Oils (EOs) are natural metabolic products of plants that contain a condensed chemical hydrophobic liquid compounds. The aim of this study was to evaluate inhibitory effects of EOs of Cinnamon zeylanicum and Myristica fragrans against Brucella abortus 544 inoculated in fresh Baladi cheese.&#x0D; Methods: Fresh Baladi cheese was manufactured from experimentally contaminated milk with B. abortus 544 in combination of EOs of C. zeylanicum or M. fragrans. Cheese samples were periodically subjected to further microbiological surveys at different storage times (0, 1, 24, 48, 72, and 96 h). The inhibition zone diameter and Minimum Inhibitory Concentration (MIC) against tested strain were also determined. Statistical analyses were conducted by GraphPad Prism Statistical Software.&#x0D; Results: The inhibition zone diameter of the paper disk were 9.5±0.5 and 16±0.57 mm at 1% concentration of M. fragrans and C. zeylanicum EOs, respectively; and 15±0.28 and 21±0.76 mm at 5% concentration of M. fragrans and C. zeylanicum EOs, respectively. The values of inhibition zone diameters were significantly (p&lt;0.0001) different between the two selected concentrations of 1% and 5% for the studied EOs. Also, anti-Brucella activity of C. zeylanicum was significantly (p&lt;0.0001) more than that of M. fragrans EO.&#x0D; Conclusion: Due to the appropriate anti-Brucella activity, C. zeylanicum EO could be applied as an effective natural preservative in the production of fresh Baladi cheese. Conversely, using M. fragrans EO could not protect the fresh Baladi cheese against Brucella.

Chemical composition, aphicidal and antiacetylcholinesterase activities of essential oils against Aphis nerii Boyer de Fonscolombe (Hemiptera: Aphididae)

Abstract Aphids are important sucking insects that attack many crops and cause huge economic loss. Essential oils have been proposed to be appropriate alternative to synthetic insecticides due to their low impact on environment and human health. In this work, the chemical compositions of eight essential oils extracted from plants growing in Egypt were determined by gas chromatography/mass spectrometry (GC–MS). The aphicidal activities of the isolated oils were examined against the adults of oleander aphid, Aphis nerii by a leaf-dipping assay. The inhibitory effect of essential oils on acetylcholinesterase (AChE) activity was also tested in vitro. Chemical analyses showed the essential oils consisted mainly of monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons and oxygenated sesquiterpenes except the oil of Artemisia monosperma which contained high content of benzenes. The results of toxicity assay showed that the oils of A. monosperma and Citrus sinensis were the most potent toxicants displaying LC50 value of 0.06 mg/L. The oils of Callistemon viminals, Schinus terebinthifolius and Schinus molle were also highly effective against aphid as their LC50 values were lower than 1 mg/L. In addition, the highest inhibitory effect on AChE was recorded by 0.5 mg/L C. sinensis with inhibition of 49.33%, while 0.1 mg/L Citrus lemon oil recorded the lowest inhibitory effect with inhibition of 0.4%. In general, six of tested essential oils showed high toxicity against A. nerii and they might be applied in the IPM programs for this insect.

Inhibitory Effect of Essential Oil Against Oral Pathogens

Inhibitory Effect of Essential Oil Against Oral Pathogens

Inhalation of Essential Oil from Mentha piperita Ameliorates PM10-Exposed Asthma by Targeting IL-6/JAK2/STAT3 Pathway Based on a Network Pharmacological Analysis.

Fine particulate matter (PM) exposure exhibits a crucial risk factor to exacerbate airway epithelial remodeling, fibrosis, and pulmonary destruction in asthma. Based on the use of essential oils from aromatic plants on pain relief and anti-inflammatory properties, we investigated the inhibitory effects of essential oil derived from the Mentha species (MEO) against asthma exposed to PM10. The MEO (0.1 v/v %) was aerosolized by a nebulizer to ovalbumin and PM10-induced asthmatic mice. Histological changes were confirmed in the lung tissues. To define the mode of action of the MEO on asthma, a protein–protein interaction network was constructed using menthol and menthone as the major components of the MEO. Cytokine expression and the JAK2/STAT3 signaling pathway were analyzed in lung epithelial A549 cells co-treated with MEO and PM10. Inhalation of MEO by nebulization inhibited respiratory epithelium hyperplasia, collagen deposition, and goblet cell activation in asthmatic mice. Through a network pharmacological analysis, cytokine–cytokine receptor interaction and JAK/STAT was expected to be underlying mechanisms of MEO on asthma. Treatment with MEO significantly reduced the IL-6 levels with a decrease in pro-inflammatory and T helper 2-specific cytokines. PM10-induced phosphorylation of JAK2 and STAT3 was significantly decreased by MEO. Collectively, MEO may have an inhibitory effect on asthma under the condition of PM10 exposure through the IL-6/JAK2/STAT3 signaling pathway.