Search Results (36)

Many aromatic herbs are conventionally used for flavoring various foods, but receive wide attention because of the variety of health-related properties. The aromatic herbs can be used either fresh or as dried powders and in the form of extracts, essential oils, or purified metabolites. In this review, the main functional properties, in terms of antioxidant and antimicrobial properties, and the applications of some of the commonly used aromatic herbs from the Lamiaceae family, are discussed. Herbs like oregano, rosemary, sage, thyme, summer savory, marjoram, and basil possess high levels of bioactive phytochemicals. They are particularly rich in phenolic acids, flavones, phenolic diterpenes, and flavanones, with various beneficial effects. The phytochemical profile of aromatic plants is highly influenced by genetic factors, environmental conditions, and their interaction. In cases of the extracts and essential oils, the extraction method has a strong effect on the final composition of the herb products. Most of the applications of these aromatic herbs are related to their antioxidant, antimicrobial, and flavoring properties. In particular, aromatic herb extracts and essential oils have multiple applications in fields like food, feed, pharmaceutical, cosmetics, biopesticides, and textile industries. Full article

Origanum majorana L., also known as sweet marjoram, is a plant with multiple uses, both in the culinary field and traditional medicine, because of its major antioxidant, anti-inflammatory, antimicrobial, and digestive properties. In this research, we focused on the effects of O. majorana essential oil (OmEO, at concentrations of 25, 150, and 300 μL/L), evaluating chemical structure as well as its impact on cognitive performance and oxidative stress, in both naive zebrafish (Danio rerio), as well as in a scopolamine-induced amnesic model (SCOP, 100 μM). The fish behavior was analyzed in a novel tank-diving test (NTT), a Y-maze test, and a novel object recognition (NOR) test. We also investigated acetylcholinesterase (AChE) activity and the brain’s oxidative stress status. In parallel, we performed in silico predictions (research conducted using computational models) of the pharmacokinetic properties of the main compounds identified in OmEO, using platforms such as SwissADME, pKCSM, ADMETlab 2.0, and ProTox-II. The results revealed that the major compounds were trans-sabinene hydrate (36.11%), terpinen-4-ol (17.97%), linalyl acetate (9.18%), caryophyllene oxide (8.25%), and α-terpineol (6.17%). OmEO can enhance memory through AChE inhibition, reduce SCOP-induced anxiety by increasing the time spent in the top zone in the NTT, and significantly reduce oxidative stress markers. These findings underscore the potential of using O. majorana to improve memory impairment and reduce oxidative stress associated with cognitive disorders, including Alzheimer’s disease (AD). Full article

Eggs are considered a nutritionally complete food and an excellent source of protein. However, they are prone to bacterial contamination, which can affect their internal quality and safety. This study aimed to evaluate the effectiveness of essential oils (EOs) as natural sanitizers for eggshells to reduce the bacterial load and improve shelf life. Ten EOs—cinnamon, clove, lavender, peppermint, thyme, rosemary, green tea, mustard, basil, and marjoram—were tested for antibacterial activity against three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis, and Listeria monocytogenes) and three Gram-negative bacteria (Salmonella Enteritidis, Pseudomonas aeruginosa, and Escherichia coli) using the well diffusion method. The most effective EOs were assessed in vapor form using a disc volatilization technique. A total of 288 eggs from a local farm in South Lebanon were treated with selected EOs and stored at room temperature for three weeks to evaluate microbial load and quality. The eggs were grouped into six categories: dry control, ultraviolet (UV) treated, and eggs sprayed with EOs, based on the recorded minimum inhibitory concentration (MIC) values. At each time point, 12 eggs from each group were analyzed for microbiological testing and external and internal quality. Results indicated that nine of the ten EOs showed antibacterial activity, with the highest inhibition zones recorded for cinnamon against S. Enteritidis (14 mm) and E. coli (9 mm), peppermint against P. aeruginosa (10 mm), and rosemary against L. monocytogenes (22 mm), S. aureus (19 mm), and E. faecalis (12 mm). Vapor phase testing showed that rosemary, thyme, clove, and cinnamon EOs had average inhibition zones ranging from 21 to 33 mm against the tested bacteria, and peppermint EO achieved complete inhibition of P. aeruginosa. Clove EO consistently reduced the bacterial load as a sanitizer on eggs, initially achieving complete inhibition. While egg quality parameters such as weight, shell thickness, Haugh unit, and yolk color declined over time, EOs helped maintain better quality compared to dry controls. GC-MS analysis of the tested EOs revealed that monoterpene alcohols are the major constituents of most oils. This study concludes that EOs are effective natural sanitizers for eggs, enhancing safety and preserving quality during storage. Full article

In recent years, the anti-corrosive properties of natural extracts as environmentally friendly inhibitors have gained considerable interest. This study evaluates the potential of Marjoram (Origanum majorana L.) essential oil (OML), collected from Salé, Morocco, as a corrosion inhibitor for mild steel in 1 M HCl medium. The protection performance of OML was assessed using various electrochemical techniques, including potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS), as well as the weight loss method. The influence of OML concentration and temperature on the inhibition performance were investigated. OML demonstrated pronounced inhibitory benefits via increasing the corrosion resistance of mild steel in the corrosive HCl solution, thus reducing the corrosion rate to 0.11 mg cm⁻² h⁻¹ and increasing the inhibition efficiency to 87.1% at an inhibitor concentration of 500 ppm. PDP confirmed that the inhibitor works as a mixed-type inhibitor with cathodic supremacy. EIS revealed that the charge transfer mechanism is the main controlling factor for the corrosion process. The thermodynamic parameters suggested a key role of OML physisorption in inhibition, following the Langmuir isotherm. Importantly, SEM and EDX analyses suggested the formation of a protective layer of the extract onto the steel surface, which shields the surface from corrosive species. This is owed to the functional group-rich phytochemicals of OML. Therefore, the development of bio-based corrosion inhibitors is not only a step towards more eco-friendly industrial practices, but also meets the growing demand for sustainable materials in a world with constrained resources. Full article

Recent reports of P. olsonii causing postharvest rot of cherry tomatoes emphasize the need for effective strategies to prolong fruit shelf life. This study is the first to explore the use of essential oils (EOs), recognized for their antimicrobial properties, as a potential method to prevent postharvest losses from P. olsonii. Antifungal activity was tested for ten EOs at a concentration of 625 μL/L using the vapor diffusion method. Thyme, wild thyme, savory, oregano, and marjoram completely inhibited fungal growth over 14 days. Thyme EO, at a minimum inhibitory concentration (MIC) of 250 μL/L, fully inhibited all strains, while oregano, wild thyme, and savory were effective at 500 μL/L. Marjoram EO showed weaker activity. The lowest IC90 values, ranging from 35.72 to 162.72 μL/L, were estimated for thyme and oregano. In cherry tomatoes, oregano EO completely halted P. olsonii growth at 250 μL/L; thyme was effective for seven days; wild thyme and savory for two days. Thyme EO prevented P. olsonii spore germination at 500 μL/L for seven days, though germination occurred at half that concentration. The IC90 values varied between 256.2 and 138.7 μL/L depending on the strain. The vapor phase of EOs at 125 μL/L influenced the sensory characteristics of cherry tomatoes; however, for thyme and oregano, this effect was not negative due to their culinary association with tomato flavor. The selected EOs could be used to control and prevent postharvest fruit losses, but further research is needed to optimize their application. Full article

In this study, in vitro and in silico approaches were employed to assess the toxicity of marjoram (Origanum majorana) and rosemary (Rosmarinus officinalis) essential oils (EOs) to A. ipsilon larvae. The study determined the activities of ATPases in the larvae after treatment with the LC₂₀ and LC₇₀ of each EO. α-esterase and glutathione-S-transferase (GST) activities were also determined after treatment with LC₁₀ and LC₃₀ of each EO. Furthermore, molecular docking was employed to determine the binding affinity of terpinene-4-ol and α-pinene, the major constituents of O. majorana, and R. officinalis EOs, respectively, compared to the co-crystallized ligand of α-esterase, diethyl hydrogen phosphate (DPF). Toxicity assays revealed that O. majorana EO was more toxic than R. officinalis EO to the A. ipsilon larvae at 96 h post-treatment. However, the LC₂₀ and LC₇₀ of the latter significantly inhibited the activity of the Na⁺-K⁺ pump at almost all intervals. The same concentrations significantly inhibited the Mg²⁺/Ca²⁺-ATPase and Ca²⁺ pump at 96 h post-treatment. In contrast, O. majorana EO showed a variable effect on the Na+-K+ pump across different time intervals. On the other hand, LC₁₀ and LC₃₀ of both EOs showed varied effects on α-esterase and GST over time. Molecular docking revealed energy scores of −4.51 and −4.29 kcal/mol for terpinene-4-ol and α-pinene, respectively, compared to a score of −4.67 for PDF. Our study demonstrated the toxicity of the tested EOs to A. ipsilon, suggesting their potential efficacy as insecticides. Full article

Plant essential oils are important alternatives in green integrated pest management. This study examined the chemical composition, bioactivity, and control efficacy of four Lamiaceae essential oils (EOs) against Thrips flavus Schrank in laboratory conditions with the goal of exploiting plant-derived insecticides to control Thrips flavus. The four EOs tested were marjoram oil (Origanum majorana L.), clary sage oil (Salvia sclarea L.), perilla leaf oil (Perilla frutescens (L.) Britt.), and spearmint oil (Mentha spicata L.). All these EOs exhibited a certain degree of insecticidal activity against Thrips flavus. The median lethal concentration (LC₅₀) was determined after treatment by the leaf-dipping method in laboratory bioassays, and its values were 0.41 mg/mL for marjoram oil, 0.42 mg/mL for clary sage oil, 0.43 mg/mL for perilla leaf oil, and 0.54 mg/mL for spearmint oil. In the pot experiment, the number of dead insects was recorded at 1, 3, and 7 days post-application, and the control efficacy of EOs against Thrips flavus was calculated. The concentration of 900.00 g a.i.·hm⁻² of spearmint oil was 100% lethal against Thrips flavus after treating potted plants for seven days. The Y-tube olfactometer method was used to test for the attraction or repellent response of EOs against Thrips flavus. The spearmint oil significantly attracted female adults in the olfactory test. Furthermore, gas chromatography–mass spectrometry (GC–MS) was used to examine the chemical composition of the EOs. Linalool (24.52%), isopropyl myristate (28.74%), (+)-limonene (32.44%), and (+)-carvone (70.3%) were their primary ingredients. The findings suggest that all four EOs are highly effective against Thrips flavus and may be a possible alternative in the management of Thrips flavus, especially when considering reducing the use of synthetic pesticides. Full article

With the recent trend of global warming, HS-instigated diminishing could extremely jeopardize animal health, productivity, and farm profit. Marjoram essential oil (MEOE) is a worthy source of wide range phytogenic compounds that may improve heat tolerance, redox and inflammatory homeostasis, and immunity of newly weaned rabbits, specifically if included in the diets in a nano form. One hundred newly weaned rabbits were randomly distributed into four homogeneous groups. The first group (control group) included rabbits that received basal diet without supplementation. In contrast, the other three groups included rabbits that received basal diets supplemented with 200 (MEONE200), 400 (MEONE400), and 800 (MEONE800) mg MEONE/kg diet, respectively. Among MEONE-treated groups and control groups, MEONE400 group showed the highest (p < 0.001) growth performance traits, including final body weight, average daily gain, feed efficiency, and the performance index. Compared to the control, all MEONE-supplemented groups possessed lower rectal temperatures and respiration rates, recording the lowest values in the MEONE400 group. The oxidative stress biomarkers and immunoglobulins G and M were significantly improved in the MEONE400 and MEONE800 compared with the control and MEONE200 groups. The addition of MEONE (400 or 800 mg/kg) decreased the concentrations of serum interleukin-4 (p = 0.0003), interferon gamma (p = 0.0004), and tumor necrosis factor-α (p < 0.0001) but significantly elevated (p < 0.001) the activity of nitric oxide, amyloid A and lysozyme. Liver functions (lower concentrations of liver enzymes) were significantly improved in all MEONE-treated groups compared to the control group. There was a considerable significant effect of dietary supplementation of MEONE400 on economic efficiency. In conclusion, the addition of 400 mg/kg to the diets of newly weaned rabbits can be recommended as an affective intervention to mitigate the negative impacts of HS. Full article

Oregano and marjoram are important aromatic spices in the food industry, as well as medicinal plants with remarkable antioxidant properties. Despite their popularity, little is known about treatments that would influence the antioxidant capacity of essential oils. In this study, different spectra of LED light, namely blue, red, white, blue-red, and natural ambient light as a control, were applied to assess the essential oil content, composition, flavonoid, phenolic, and antioxidant capacity of oregano and marjoram. GC-MS analysis revealed thymol, terpinen-4-ol, sabinene, linalool, p-cymene, and γ-terpinene as the main compounds. In oregano, the thymol content ranged from 11.91% to 48.26%, while in marjoram it varied from 17.47% to 35.06% in different samples. In oregano and marjoram, the highest phenolic contents were in blue (61.26 mg of tannic acid E/g of DW) and in white (65.18 mg of TAE/g of DW) light, respectively, while blue-red illumination caused the highest increase in total flavonoids. The antioxidant activity of oregano and marjoram extract was evaluated using two food model systems, including DPPH and β-carotene bleaching. The highest antioxidant capacity was obtained in control light in oregano and blue-red light in marjoram. The results provide information on how to improve the desired essential oil profile and antioxidant capacity of extracts for industrial producers. Full article

The current study was performed to investigate the toxic effects of aflatoxin B1 (AFB1) through the evaluation of kidney function tests and histopathological examination of renal tissues, targeting the therapeutic role of Marjoram (Origanum vulgare essential oil-OEO) in improving health status. Forty-eight New Zealand Whites growing rabbits (four weeks old) weighing on average 660.5 ± 2.33 g were randomly and equally distributed into four groups, each of which had four replicas of three animals as the following: Control group (only basal diet), AFB1 group (0.3 mg AFB1/kg diet), OEO group (1 g OEO/kg diet) and co-exposed group (1 g OEO/kg + 0.3 mg AF/kg diet). Our study lasted eight weeks and was completed at 12 weeks of age. The results revealed that OEO decreased the toxic effects of AFB1 in rabbit kidneys by substantially reducing the cystatin C levels in the AFB1 group. Additionally, OEO decreased oxidative stress and lipid peroxidation levels in the co-exposed group. Moreover, OEO reduced DNA damage and inflammatory response in addition to the down-regulation of stress and inflammatory cytokines-encoding genes. Besides, OEO preserved the cytoarchitecture of rabbits’ kidneys treated with AFB1. In conclusion, O. vulgare essential oil supplementation ameliorated the deleterious effects of AFB1 on the rabbits’ kidneys by raising antioxidant levels, decreasing inflammation, and reversing oxidative DNA damage. Full article

Origanum marjorana L. has been valued for centuries for its flavoring attributes and therapeutic properties. The growing demand for its various applications necessitates optimizing agronomic practices for its production. A glasshouse pot trial was conducted to identify optimum agronomic practices for increased herbage and oil yield, as well as oil quality. The effects of varying air temperature regimes (low, medium, and high levels), irrigation (low, medium, and high levels), nitrogen fertilizer application (N = 100, 150, and 200 kg/ha), and soil type (sandy loam, sandy clay loam, and loamy sand) on the productivity of marjoram plants were investigated. The results showed an increase in plant growth and herbage yield as well as chlorophyll content under conditions of high air temperature, low irrigation, and moderate to high nitrogen level applied to sandy loam soil, with an increase in oil yield with loamy sand soil. The major compounds observed in marjoram essential oil were terpinene-4-ol (22.63–36.72%) and (Z)-β-terpineol (6.85–16.60%), in which terpinene-4-ol was not found to be within the International Organization for Standardization (ISO) limits of acceptability while (Z)-β- terpineol had no reference limits available. A promising performance of marjoram cultivation under high regimes of air temperature (16.7 to 36.6 °C), nitrogen fertilization (200 kg ha⁻¹ N), and low irrigation (up to 60% soil water depletion from field capacity) on sandy loam soils was demonstrated for improved crop productivity. Full article

Essential oils have been known about since ancient times and have been used in aromatherapy. Nowadays, their applications also cover the medicine and food industries due to their wide spectrum of bioactivity, including antioxidant properties. Thus, the estimation of essential oils’ antioxidant properties is of practical interest. Phenolic compounds and terpenes are the major antioxidants present in essential oils according to gas chromatography-mass spectrometry (GC-MS). Total antioxidant parameters are a good alternative to the characterization of individual components by GC-MS, allowing the avoidance of a time-consuming and expensive procedure. Coulometric titration with electrogenerated bromine and ferricyanide ions has been used for the estimation of the total antioxidant capacity and the ferric reducing power of essential oils for the first time. Data on the reaction of individual antioxidants (volatile phenolics and terpenes) with coulometric titrants confirm the applicability of the method for the characterization of essential oils’ antioxidant properties. The essential oils clove, cinnamon, nutmeg, lavender, ginger, anise, basil, bergamot, jasmine, ylang-ylang, marjoram, neroli, rosemary, thyme, and clary sage of various trademarks (total 27 samples) are investigated. The data are compared to the standard parameters (antioxidant activity towards 2,2-diphenyl-1-picrylhydrazyl and the total phenolic contents). Positive correlations with coefficients from 0.7051 to 0.9558 confirm the accuracy of the coulometric approach. Moreover, the ferric reducing power reflecting the phenolic antioxidant content can be used for all samples of essential oils, while the Folin–Ciocalteu method for total phenolic contents is applicable to four essential oils only. Another advantage of coulometry titration is the possibility of automation and its rapidity, making it an attractive tool for screening purposes in routine practice. Full article

Origanum majorana is a medicinal and aromatic plant that belongs to the Lamiaceae family. It is cultivated in several parts of the world and, due to its splendid aroma and taste, is widely used for culinary purposes and in perfumes. The essential oil of the plant, to which is attributed its aroma, contains many secondary metabolites with valuable biological activity. One of them is the pesticide activity, which has attracted much interest. Given the necessity of replacing synthetic pesticides, essential oils are studied in an attempt to find naturally derived products. Thus, the aim of this review paper is to discuss the chemical profile of O. majorana essential oil and to present data regarding its insecticidal, repellent and fumigant activity. Data were collected from 1992 to 2022. Databases, including PubMed, Google Scholar, ScienceDirect and Scopus, were used for the research, and keywords, including O. majorana, sweet marjoram, essential oil, volatiles, pesticide, insecticide and repellent activity, were used. The results of this review paper indicate that O. majorana essential oil can be an alternative agent to manage pests. However, still, much research should be conducted to evaluate its toxicity against beneficial insects and to ensure its safety for human health. Full article

Spanish marjoram (Thymus mastichina) and cardamom (Elettaria cardamomum) are traditional aromatic plants with which several pharmacological properties have been associated. In this study, the volatile composition, antioxidative and antimigratory effects on human breast cancer (MDA-MB-468 cell line), antimicrobial activity, and antibiofilm effect were evaluated. Results obtained via treatment of human breast cancer cells generally indicated an inhibitory effect of both essential oils (EOs) on cell viability (after long-term treatment) and antioxidative potential, as well as the reduction of nitric oxide levels. Antimigratory effects were revealed, suggesting that these EOs could possess significant antimetastatic properties and stop tumor progression and growth. The antimicrobial activities of both EOs were determined using the disc diffusion method and minimal inhibition concentration, while antibiofilm activity was evaluated by means of mass spectrometry. The best antimicrobial effects of T. mastichina EO were found against the yeast Candida glabrata and the G⁺ bacterium Listeria monocytogenes using the disc diffusion and minimal inhibitory concentration methods. E. cardamomum EO was found to be most effective against Pseudomas fluorescens biofilm using both methods. Similarly, better effects of this oil were observed on G⁻ compared to G⁺ bacterial strains. Our study confirms that T. mastichina and E. cardamomum EOs act to change the protein structure of older P. fluorescens biofilms. The results underline the potential use of these EOs in manufactured products, such as foodstuffs, cosmetics, and pharmaceuticals. Full article

Mosquitoes are one of the most important disease vectors from a medical viewpoint in that they transmit several diseases such as malaria, filariasis, yellow and Dengue fever. Mosquito vector control and personal protection from mosquito bites are currently the most efficient ways to prevent these diseases. Several synthetic repellents such as DEET, ethyl butylacetylaminopropionate (IR3535) and 1-(1-methylpropoxycarbonyl)-2-(2-hydroxyethyl)piperidine) (Picaridin), have been widely used to prevent humans from receiving mosquito bites. However, the use of synthetic repellents has raised several environment and health concerns. Therefore, essential oils (EOs) as natural alternatives receive our attention. In order to discover highly effective mosquito repellents from natural sources, the repellent activity of 60 commercial EOs against Ae. albopictus was screened in this study. Eight EOs including cinnamon, marjoram, lemongrass, bay, chamomile, jasmine, peppermint2, and thyme, showed a suitable repellent rate (>40%) at the tested dose of 10 μg/cm². Then, their main constituents were analyzed by GC-MS, and the active constituents were identified. The most active compounds including cinnamaldehyde, citral and terpinen-4-ol, exhibited an 82%, 65% and 60% repellent rate, respectively. Moreover, the nanoemulsions of the three active compounds were prepared and characterized. In the arm-in-cage assay, the protection times of the nanoemulsions of cinnamaldehyde and citral were significantly extended compared with their normal solutions. This study provides several lead compounds to develop new mosquito repellents, and it suggests that nanoemulsification is an effective method for improving the duration of the activity of natural repellents. Full article