Chemical Composition and Antimicrobial Properties of Mentha × piperita cv. 'Kristinka' Essential Oil

Sequential Separation of Essential Oil Components during Hydrodistillation of Fresh Foliage from Azorean Cryptomeria japonica (Cupressaceae): Effects on Antibacterial, Antifungal, and Free Radical Scavenging Activities

Cryptomeria japonica wood industry generates large amounts of foliage biomass residues. Due to the increasing applications and markets for essential oils (EOs), fresh Azorean C. japonica foliage (Az-CJF) residues are used for local EO production. Hydrodistillation (HD), a common process for obtaining EOs, also provides the possibility to fractionate them. Thus, this study evaluated the in vitro antimicrobial and antioxidant activities of six Az-CJF EO fractions (Frs. 1-6), collected at sequential HD timeframes (HDTs: 0-2, 2-10, 10-30, 30-60, 60-120, and 120-240 min), in comparison to the crude EO, obtained from a non-fractionated HD (0-240 min HDT). Antimicrobial activities were assessed via disc diffusion method against seven bacteria (foodborne and/or human pathogens) and two Penicillium spp. (phytopathogenic fungi), and antioxidant activity was estimated using DPPH and ABTS assays. Concerning the antibacterial activity, all the EO samples were effective only toward Gram-positive bacteria. Fractions 1-3 (<30 min HDT) were the most active, with growth inhibition zones (GIZ) of 7.0-23.3 mm (1.4-2.2 times higher than those of the crude EO), being Bacillus spp. (B. licheniformis and B. subtilis) the most sensitive, followed by Staphylococcus aureus and Micrococcus luteus. Regarding the antifungal activity, Frs. 1-3 also displayed the best activities, but only against P. italicum (GIZ around 9.0 mm), while the crude EO showed no antifungal activity. Overall, the best antimicrobial properties of Frs. 1-3 could be attributed, at least in part, to their highest content in α-pinene and bornyl acetate. On the other hand, Frs. 4-6 (>30 min HDT) exhibited the strongest antioxidant activities (EC50 values: 1.5-2.3 and 1.0-1.7 mg mL-1 for DPPH and ABTS, respectively), being at least 1.3-fold higher than those of the crude EO. The presence of nezukol, elemol, and eudesmol isomers could strongly contribute to the best free radical scavenging properties of Frs. 4-6. In conclusion, HD was found to be an efficient process for obtaining new Az-CJF EO fractions with variable and enhanced bioactivities due to their differential composition, as assessed using GC-MS. Hence, these findings could contribute to increasing the commercial potential of the C. japonica EO industry, namely, the Fr2 and Fr6, which presented the most significant activities and can have potential applications in the food, medical, and agriculture sectors.

Synergistic antimicrobial interaction of plant essential oils and extracts against foodborne pathogens

Essential oils (EOs) and plant extracts have demonstrated inhibitory activity against a wide range of pathogenic bacteria. In this study, the chemical composition of manuka, kanuka, peppermint, thyme, lavender, and feijoa leaf and peel EOs and feijoa peel and leaf extracts were analyzed, and their antimicrobial activity against Escherichia coli, Salmonella enterica Typhimurium, Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes were determined. The results showed that the major compounds varied among different EOs and extracts, with menthol in peppermint EO, thymol and carvacrol in thyme EO, linalool in lavender EO, β-caryophyllene in feijoa EO, and flavones in feijoa extract being the most prevalent. The study found that while EOs/extracts had antimicrobial activity alone, no individual EO/extract was highly effective against all tested species. Therefore, their combinations were tested to identify those that could broaden the spectrum of activity and act synergistically. The checkerboard method was applied to assess the possible synergism between the paired combinations of EOs/extract. The peppermint/thyme, peppermint/lavender, and peppermint/feijoa peel extract combinations exhibited a synergistic effect against E. coli and L. monocytogenes, with the peppermint/thyme and peppermint/feijoa peel extract combinations being the most effective against all five pathogens. Time-to-kill kinetics assays demonstrated that peppermint/thyme and peppermint/feijoa peel extract combinations achieved complete eradication of E. coli within 10-30 min and L. monocytogenes within 4-6 h. This study provides a promising approach to developing a natural alternative for food preservation using synergistic combinations of EOs/extracts, which could potentially reduce the required dosage and broaden their application in food products as natural preservatives.

Essential Oils of Mentha arvensis and Cinnamomum cassia Exhibit Distinct Antibacterial Activity at Different Temperatures In Vitro and on Chicken Skin

The bacterial contamination of meat is a global concern, especially for the risk of Salmonella infection that can lead to health issues. Artificial antibacterial compounds used to preserve fresh meat can have negative health effects. We investigated the potential of natural essential oils (EOs), namely Mentha arvensis (mint) and Cinnamomum cassia (cinnamon) EOs, to prevent contamination of the food pathogen, Salmonella enterica subsp. enterica serotype Typhimurium, in vitro and on chicken skin. The gas chromatography-mass spectrometry (GC-MS) technique was used to determine the compositions of mint EO (MEO) and cinnamon EO (CEO); the most abundant compound in MEO was menthol (68.61%), and the most abundant compound was cinnamaldehyde (83.32%) in CEO. The antibacterial activity of MEO and CEO were examined in vapor and direct contact with S. typhimurium at temperatures of 4 °C, 25 °C, and 37 °C. The minimal inhibitory concentration at 37 °C for MEO and CEO reached 20.83 µL/mL, and the minimal bactericidal concentration of CEO was the same, while for MEO, it was two-fold higher. We report that in most tested conditions in experiments performed in vitro and on chicken skin, CEO exhibits a stronger antibacterial effect than MEO. In the vapor phase, MEO was more effective against S. typhimurium than CEO at 4 °C. In direct contact, the growth of S. typhimurium was inhibited more efficiently by MEO than CEO at small concentrations and a longer exposure time at 37 °C. The exploration of CEO and MEO employment for the inhibition of Salmonella bacteria at different temperatures and conditions expands the possibilities of developing more environment- and consumer-friendly antibacterial protection for raw meat.

GC-MS, quantum mechanics calculation and the antifungal activity of river red gum essential oil when applied to four natural textiles

The most important uses of old fabrics include clothing, mummification, and bookbinding. However, because they are predominantly constructed of natural materials, they are particularly susceptible to physical and chemical deterioration brought on by fungi. The treatments that are typically used to preserve old textiles focus on the use of synthetic fungicides, which have the potential to be dangerous for both human health and the environment. Essential oils (EOs), which are safe for the environment and have no negative effects on human health, have been widely advocated as an alternative to conventional antifungals. Four natural fabrics-linen, cotton, wool, and silk-were utilized in the current work. The extracted EO from leaves of river red gum (Eucalyptus camaldulensis Dehnh.) were prepared at 125, 250, and 500 µL/L. Aspergillus flavus, Fusarium culmorum and Aspergillus niger were inoculated separately into the treated four fabrics with the EO at concentrations of 125, 250, and 500 µL/L or the main compounds (spathulenol and eucalyptol) at the concentrations of 6, 12, 25, and 50 µL/L and were then compared to the un-treated samples. GC-MS was used to analyze the EO chemical composition, while visual observations and scanning electron microscopic (SEM) were used to study the fungal growth inhibition. Spathulenol (26.56%), eucalyptol (14.91%), and p-cymene (12.40%) were the principal chemical components found in E. camaldulensis EO by GC-MS. Spathulenol molecule displayed the highest electrostatic potential (ESP) compared with the other primary compound, as calculated by quantum mechanics. In the untreated textile samples, SEM analysis revealed substantial proliferation of hyphae from A. flavus, F. culmorum, and A. niger. The fungal growth was completely inhibited at a concentration of 500 µL/L from the EO. Both eucalyptol and spathulenol completely inhibited the formation of the fungal spores at a concentration of 50 µL/L, although eucalyptol was more effective than spathulenol across the board for all four textiles. The results support E. camaldulensis EO functionalized textiles as an effective active antifungal agent.

Antibiofilm mechanism of peppermint essential oil to avert biofilm developed by foodborne and food spoilage pathogens on food contact surfaces

Establishing efficient methods to combat bacterial biofilms is a major concern. Natural compounds, such as essential oils derived from plants, are among the favored and recommended strategies for combatting bacteria and their biofilm. Therefore, we evaluated the antibiofilm properties of peppermint oil as well as the activities by which it kills bacteria generally and particularly their biofilms. Peppermint oil antagonistic activities were investigated against Vibrio parahaemolyticus, Listeria monocytogenes, Pseudomonas aeruginosa, Escherichia coli O157:H7, and Salmonella Typhimurium on four food contact surfaces (stainless steel, rubber, high-density polyethylene, and polyethylene terephthalate). Biofilm formation on each studied surface, hydrophobicity, autoaggregation, metabolic activity, and adenosine triphosphate quantification were evaluated for each bacterium in the presence and absence (control) of peppermint oil. Real-time polymerase chain reaction, confocal laser scanning microscopy, and field-emission scanning electron microscopy were utilized to analyze the effects of peppermint oil treatment on the bacteria and their biofilm. Results showed that peppermint oil (1/2× minimum inhibitory concentration [MIC], MIC, and 2× MIC) substantially lessened biofilm formation, with high bactericidal properties. A minimum of 2.5-log to a maximum of around 5-log reduction was attained, with the highest sensitivity shown by V. parahaemolyticus. Morphological experiments revealed degradation of the biofilm structure, followed by some dead cells with broken membranes. Thus, this study established the possibility of using peppermint oil to combat key foodborne and food spoilage pathogens in the food processing environment.

Chamaecyparis lawsoniana Leaf Essential Oil as a Potential Anticancer Agent: Experimental and Computational Studies

Cancer remains one of the leading causes of death worldwide, affected by several factors including oxidative stress; and although conventional synthetic medicines have been used to treat cancer, they often result in various side effects. Consequently, there is a growing need for newer, safer and more effective alternatives, such as natural plant products. Essential oils (EOs) are one such alternative, offering a wide range of bioactivities, including antibacterial, antiviral, antioxidant, and anticancer properties. Accordingly, the objective of the present study was to investigate the chemical composition, as well as the antioxidant and anticancer properties of the leaf essential oil of Chamaecyparis lawsoniana (CLLEO) belonging to the Cupressaceae family. Totally, 59 constituents were identified by gas chromatography-mass spectrometry (GC-MS) analysis. cis-Abienol, trans-ferruginol, α-cadinol, δ-muurolene and α-pinene were the major components. The in vitro cytotoxicity study against human breast (MCF-7), colon (HCT-116), lung (A-549), hepatocellular (HepG-2) carcinoma cells using MTT assay indicated a promising cytotoxic activity against all the tested cancer cells, particularly HepG-2, with significant selectivity indices. CLLEO exhibited weak antioxidant activity according to the DPPH, ABTS and FRAP assays. In silico docking of these constituents against the epidermal growth factor receptor (EGFR), the myeloid cell leukemia-1 (Mcl-1) and caspase-8 using Molecular Operating Environment (MOE) software demonstrated good binding affinities of the components with the active site of these targets. These findings suggested using CLLEO, or its individual components, as a potentially viable therapeutic option for managing cancerous conditions.

Antifungal activity of a novel synthetic polymer M451 against phytopathogens

Phytopathogenic fungi are the predominant causal agents of plant diseases. Available fungicides have substantial disadvantages, such as being insufficiently effective owing to intrinsic tolerance and the spread of antifungal resistance accumulating in plant tissues, posing a global threat to public health. Therefore, finding a new broad-spectrum fungicide is a challenge to protect plants. We studied the potency of a novel antimicrobial agent, M451, a 1,6-diaminohexane derivative, against different phytopathogenic fungi of the Ascomycota, Oomycota, and Basidiomycota phyla. M451 exhibited significant antifungal activity with EC₅₀ values from 34-145 μg/mL. The minimal fungicidal concentration against Fusarium oxysporum ranged from 4 to 512 μg/mL depending on the exposure times of 5 min to 24 h. M451 has the highest activity and significantly lower exposure times compared to different polyene, azole, and phenylpyrrole antifungals. The conidial germination assay revealed that M451 induced 99 and 97.8% inhibition against F. oxysporum within 5 min of exposure to 5,000 and 500 μg/mL, respectively. Germ tube elongation, spore production, and spore germination were also significantly inhibited by M451 at concentrations of ≥50 μg/mL. Based on the broad spectrum of antifungal effects across different plant pathogens, M451 could be a new chemical fungicide for plant disease management.

Enhancing the Antimicrobial Effect of Ozone with Mentha piperita Essential Oil

This study aimed to obtain and analyse Mentha piperita essential oil (MpEO) for the prospect of being used as an enhancement agent for the antimicrobial potential of ozone against gram-positive and gram-negative bacteria and fungi. The research was done for different exposure times, and it gained time-dose relationships and time-effect correlations. Mentha piperita (Mp) essential oil (MpEO) was obtained via hydrodistillation and further analysed by using GC-MS. The broth microdilution assay was used to determine the strain inhibition/strain mass growth by using spectrophotometric optical density reading (OD). The bacterial/mycelium growth rates (BGR/MGR) and the bacterial/mycelium inhibition rates (BIR/MIR) after ozone treatment in the presence and absence of MpEO on the ATTC strains were calculated; the minimum inhibition concentration (MIC) and statistical interpretations of the time-dose relationship and specific t-test correlations were determined. The effect of ozone on the following tested strains at maximum efficiency was observed after 55 s of single ozone exposure, in order of effect strength: S. aureus > P. aeruginosa > E. coli > C. albicans > S. mutans. For ozone with the addition of 2% MpEO (MIC), maximum efficacy was recorded at 5 s for these strains, in order of effect strength: C. albicans > E. coli > P. aeruginosa > S. aureus > S. mutans. The results suggest a new development and affinity regarding the cell membrane of the different microorganisms tested. In conclusion, the use of ozone, combined with MpEO, is sustained as an alternative therapy in plaque biofilm and suggested as helpful in controlling oral disease-causing microorganisms in medicine.

A Comprehensive Review on the Biological, Agricultural and Pharmaceutical Properties of Secondary Metabolites Based-Plant Origin

Natural products are compounds produced by living organisms and can be divided into two main categories: primary (PMs) and secondary metabolites (SMs). Plant PMs are crucial for plant growth and reproduction since they are directly involved in living cell processes, whereas plant SMs are organic substances directly involved in plant defense and resistance. SMs are divided into three main groups: terpenoids, phenolics and nitrogen-containing compounds. The SMs contain a variety of biological capabilities that can be used as flavoring agents, food additives, plant-disease control, strengthen plant defenses against herbivores and, additionally, it can help plant cells to be better adapted to the physiological stress response. The current review is mainly focusing on certain key elements related to the significance, biosynthesis, classification, biochemical characterization and medical/pharmaceutical uses of the major categories of plant SMs. In addition, the usefulness of SMs in controlling plant diseases, boosting plant resistance and as potential natural, safe, eco-friendly substitutes for chemosynthetic pesticides were also reported in this review.

Anti-Heliobacter pylori and Anti-Inflammatory Potential of Salvia officinalis Metabolites: In Vitro and In Silico Studies

Due to its rising antibiotic resistance and associated inflammations, Helicobacter pylori poses a challenge in modern medicine. Salvia officinalis, a member of the Lamiaceae family, is a promising medicinal herb. In this regard, a phytochemical screening followed by GC-MS and LC-MS was done to evaluate the chemical profile of the total ethanolic extract (TES) and the essential oil, respectively. The anti-H. pylori and the anti-inflammatory activities were evaluated by a micro-well dilution technique and COX-2 inhibition assay. Potential anti-H. pylori inhibitors were determined by an in silico study. The results revealed that the main metabolites were flavonoids, sterols, volatile oil, saponins, and carbohydrates. The LC-MS negative ionization mode demonstrated 12 compounds, while GC-MS showed 21 compounds. Carnosic acid (37.66%), epirosmanol (20.65%), carnosol1 (3.3%), and 12-O-methyl carnosol (6.15%) were predominated, while eucalyptol (50.04%) and camphor (17.75%) were dominant in LC-MS and GC-MS, respectively. TES exhibited the strongest anti-H. pylori activity (3.9 µg/mL) asymptotic to clarithromycin (0.43 µg/mL), followed by the oil (15.63 µg/mL). Carnosic acid has the best-fitting energy to inhibit H. pylori (-46.6769 Kcal/mol). TES showed the highest reduction in Cox-2 expression approaching celecoxib with IC₅₀ = 1.7 ± 0.27 µg/mL, followed by the oil with IC₅₀ = 5.3 ± 0.62 µg/mL. Our findings suggest that S. officinalis metabolites with anti-inflammatory capabilities could be useful in H. pylori management. Further in vivo studies are required to evaluate and assess its promising activity.

Insecticidal Activity of Essential Oils against Mealybug Pests (Hemiptera: Pseudococcidae): A Systematic Review and Meta-Analysis

Most mealybugs of the Pseudococcidae family are important pests of agriculture and ornamental gardens. Our aim was to perform a review and meta-analysis on 14 published scientific articles on the insecticidal activity of essential oils (EOs) against mealybug species of the Pseudococcidae family. Data on (1) species, genus, families, and plant parts from which the EO was extracted; (2) the main compounds of each EO; (3) the highest and lowest concentrations tested; and (4) the application method used for the toxicological studies was collected from each study. The metafor package (R software) was used to perform a three-level random effects meta-analysis. The families Lamiaceae, Rutaceae, Myrtaceae, Zingiberaceae and Euphorbiaceae and the genera Citrus, Cymbopogon, Syzygium, Cinnamomum and Jatropha were the most used among the studies. According to the results from the meta-analyses, 13 out of 24 genera analyzed were effective against mealybugs. All methods were effective, but fumigation and indirect contact were the most frequently used methodologies. The results obtained from the present review and meta-analysis could be used for the potential development of natural biopesticide formulations against mealybugs belonging to the Pseudococcidae family.

An integrated approach utilizing raman spectroscopy and chemometrics for authentication and detection of adulteration of agarwood essential oils

Agarwood is a precious aromatic plant which has good pharmacological effects such as antidepressant and sedation. It also has good ornamental and collection value. However, due to it is long and complex production process, the output of agarwood essential oils (AEOs) is scarce, so the price is expensive, the quality is uneven, and the adulteration events is endless. From the commercial and pharmaceutical point of view, the authenticity and quality of the commercial products labeled as AEOs is very important. This paper tested the applicability of Raman spectroscopy combined with chemometrics in classification and authenticity identification of AEOs. In this study, Raman spectroscopy and principal component analysis (PCA) combined with partial least square discriminant analysis (PLS-DA) were used to comprehensively evaluate AEOs from different geographical origins and/or extracted by different methods which showed different characteristic bands. The characteristic component of AEOs, chromone derivatives, and two commonly used adulterants were also detected. These characteristic bands provide spectrum information of AEO samples and reference materials, which can be used as Raman spectral markers for the qualitative identification of AEOs. This study can provide a novel, fast and convenient method for identification of AEOs.

Green Synthesized of Thymus vulgaris Chitosan Nanoparticles Induce Relative WRKY-Genes Expression in Solanum lycopersicum against Fusarium solani, the Causal Agent of Root Rot Disease

Fusarium solani is a plant pathogenic fungus that causes tomato root rot disease and yield losses in tomato production. The current study's main goal is testing the antibacterial efficacy of chitosan nanoparticles loaded with Thyme vulgaris essential oil (ThE-CsNPs) against F. solani in vitro and in vivo. GC-MS analysis was used to determine the chemical constituents of thyme EO. ThE-CsNPs were investigated using transmission electron microscopy before being physicochemically characterized using FT-IR. ThE-CsNPs were tested for antifungal activity against F. solani mycelial growth in vitro. A pot trial was conducted to determine the most effective dose of ThE-CsNPs on the morph/physiological characteristics of Solanum lycopersicum, as well as the severity of fusarium root rot. The relative gene expression of WRKY transcript factors and defense-associated genes were quantified in root tissues under all treatment conditions. In vitro results revealed that ThE-CsNPs (1%) had potent antifungal efficacy against F. solani radial mycelium growth. The expression of three WRKY transcription factors and three tomato defense-related genes was upregulated. Total phenolic, flavonoid content, and antioxidant enzyme activity were all increased. The outfindings of this study strongly suggested the use of ThE-CsNPs in controlling fusarium root rot on tomatoes; however, other experiments remain necessary before they are recommended.

Mentha: Nutritional and Health Attributes to Treat Various Ailments Including Cardiovascular Diseases

A poor diet, resulting in malnutrition, is a critical challenge that leads to a variety of metabolic disorders, including obesity, diabetes, and cardiovascular diseases. Mentha species are famous as therapeutic herbs and have long served as herbal medicine. Recently, the demand for its products, such as herbal drugs, medicines, and natural herbal formulations, has increased significantly. However, the available literature lacks a thorough overview of Mentha phytochemicals' effects for reducing malnutritional risks against cardiovascular diseases. In this context, we aimed to review the recent advances of Mentha phytochemicals and future challenges for reducing malnutritional risks in cardiovascular patients. Current studies indicated that Mentha species phytochemicals possess unique antimicrobial, antidiabetic, cytotoxic, and antioxidant potential, which can be used as herbal medicine directly or indirectly (such as food ingredients) and are effective in controlling and curing cardiovascular diseases. The presence of aromatic and flavor compounds of Mentha species greatly enhance the nutritional values of the food. Further interdisciplinary investigations are pivotal to explore main volatile compounds, synergistic actions of phytochemicals, organoleptic effects, and stability of Mentha sp. phytochemicals.

Peppermint essential oil-loaded solid lipid nanoparticle in gelatin coating: Characterization and antibacterial activity against foodborne pathogen inoculated on rainbow trout (Oncorhynchus mykiss) fillet during refrigerated storage

The present study was conducted to determine the characterization and antibacterial activity of peppermint essential oil-loaded solid lipid nanoparticle (PEO-SLN) and its impact on the quality of trout fillet stored at 4 ± 1°C for 12 days. The SLNs were prepared through a bath sonication technique. PEO-SLNs contained 0.2% (w/v) PEO in 2% of lipid phase glycerol monostearate (GMS) and tween 80 (1% w/v) used as a surfactant in the aqueous phase. The characterization parameter of PEO-SLN was evaluated, and the antibacterial activity of PEO-SLNs was conducted under in vitro conditions. Trout samples were analyzed for inoculated Pseudomonas aeruginosa, Listeria monocytogenes, and Escherichia coli O157:H7 during refrigerated storage. The mean particle size of PEO-SLNs was 154.83 ± 1.21 nm with a polydispersity index (PDI) of 0.35 ± 0.01 and zeta potential was about -24.16 ± 0.51 mV. The results indicated that PEO-SLN had higher antibacterial activity than the free form of PEO and also when used in combination with gelatin coating (gel + PEO-SLN) had a significant effect on preventing microbial growth in trout fillets (p < 0.05). The most decreasing rate of P. aeruginosa (1.92 log CFU/g), E. coli O157:H7 (0.71 log CFU/g), and L. monocytogenes count (1.69 log CFU/g) was seen in gel + PEO-SLN. These findings illustrated that PEO-SLNs could potentially be utilized in the food industry to increase the shelf life of fish fillets.

Evaluation of Bacterial Perpetuation Assays and Plant Biomolecules Antimicrobial Activity against Cotton Blight Bacterium Xanthomonas citri subsp. malvacearum; An Alternative Source for Food Production and Protection

Cotton (Gossypium hirsutum) is a global cash crop which has gained importance in earning foreign exchange for each country. Bacterial blight caused by Xanthomonascitri subsp. malvacearum (Xcm) has been a seriousdisease in Pakistan’s cotton belt on multiple occasions. Bacterium was isolated and identified through various biochemical and diagnostic tests wherehypersensitivity reaction, Gram staining, KOH (potassium hydroxide), catalase, starch hydrolysis, lecithinase and Tween 80 hydrolysis tests confirmed bacterium as Gram-negative and plant pathogenic. Xcm perpetuation assays wereevaluated on various cotton varieties under glasshouse conditions in completely randomized design by three different methods, wherein the scratch method proved to be the best upon CIM-496 and showed 83.33% disease incidence as compared with the other two methods, where Bt-3701 responded with 53.33% incidence via the spray gun method, and 50% with the water splash method on CIM-616, as compared with the control. Similarly, for disease severity percentage, Bt-3701 was pragmatic with 47.21% through scratch method, whereas, in the spray gun method, 45.51% disease severity was noted upon Bt-802, and 31.27% was calculated on Cyto-179 through the water splash method. Owing to the unique antibacterial properties of aqueous plant extracts, the poison food technique showed Aloe vera, Mentha piperita, Syzygiumcumini and Azadirachta indica with 17.77, 29.33, 18.33 and 20.22 bacterial colonies counted on nutrient agarmedium petri plate, respectively, as compared with the control. Measurement of the inhibition zone by disk diffusion technique showed Mentha piperita, Syzygiumcumini, Citrus limon, Moringa oleifera and Syzygium aromaticum to present the most promising results by calculating the maximum diameter of the inhibition zone, viz., 8.58, 8.55, 8.52, 8.49 and 8.41 (mm), respectively, at the highest tested concentration (75 ppm, parts per million) compared with the control. It is probable that the decoction’s interaction with the pathogen population on the host plant will need to be considered in future experiments. However, at this moment, more research into the effective management of cotton bacterial blight by plant extracts in terms of concentration determination and development of biopesticides will provide future avenues to avoid environmental pollution.

Evaluation of the Antimicrobial Activity of Four Plant Essential Oils against Some Food and Phytopathogens Isolated from Processed Meat Products in Egypt

Synthetic preservatives are widely utilized by the food industry to inhibit the microbial contamination and increase food safety and shelf life. The excessive utilization of synthetic preservatives can have a negative impact on human health and the environment. There is a great interest to find out natural substances as possible food-preservatives. The consumers’ preference for food products with natural ingredients prompted food manufacturers to utilize natural-based preservatives in their production. It is worth noting that plant essential oils (EOs) among the natural-based substances have been efficiently used as antimicrobial agents against phyto- and food pathogens. The current study was conducted to evaluate the microbial contamination of three industrial meat products from five governorates in Egypt, identify the predominant bacterial and fungal isolates and determine the antimicrobial efficacy of some EOs (thyme, fennel, anise and marjoram) against the most predominant microbial isolates. A sensory test was also performed to estimate the customer preferences for specific organoleptic aspects of meat products after EOs treatment. Results showed that there is a promising antimicrobial activity of all studied EOs against some microbial isolates in a dose-dependent manner. In particular, thyme EO showed the highest significant antibacterial activity against P. fluorescence and E. coli. Whereas the marjoram EO showed the highest activity against P. aeruginosa. In addition, the sensory test revealed that the treatment with anise and marjoram EOs showed the highest acceptability by the testers and did not show significant differences on the organoleptic properties with respect to control. As overall, the obtained results of the current research are promising and proved feasibility of employing plant EOs as possible preservatives for processed meat products.

Plant Essential Oil with Biological Activity

Plant essential oils (PEOs), extracted from many aromatic and medicinal plants, are used in folk medicine and often represent an important part of the traditional pharmacopoeia: they have a long history of use in folk medicine as antimicrobial agents to control several human and phyto-pathogens. Many PEOs have been registered as effective alternatives to chemical and synthetic antimicrobials, and in the last few decades, they have also been effectively used in the food industry as antioxidants and anticarcinogens, thanks to the efforts of many research/medical institutions and pharmaceutical companies. This Special Issue discussed the chemical composition and biological-pharmaceutical activities of some important PEOs and their single constituents. Detailed information has been also covered in this Special Issue regarding the mechanisms, possible modes of action, and factors affecting these activities, such as geographical origins, environmental conditions, nutritional status, and the extraction methods used.

Biochemical Characterization, Antifungal Activity, and Relative Gene Expression of Two Mentha Essential Oils Controlling Fusarium oxysporum, the Causal Agent of Lycopersicon esculentum Root Rot

Tomato (Lycopersicon esculentum Mill.) is important food in daily human diets. Root rot disease by Fusarium oxysporum caused huge losses in tomato quality and yield annually. The extensive use of synthetic and chemical fungicides has environmental risks and health problems. Recent studies have pointed out the use of medicinal plant essential oils (EOs) and extracts for controlling fungal diseases. In the current research, Mentha spicata and Mentha longifolia EOs were used in different concentrations to control F. oxysporum. Many active compounds are present in these two EOs such as: thymol, adapic acid, menthol and menthyl acetate. These compounds possess antifungal effect through malformation and degradation of the fungal cell wall. The relative expression levels of distinctly upregulated defense-related WRKY genes (WRKY1, WRKY4, WRKY33 and WRKY53) in seedling root were evaluated as a plant-specific transcription factor (TF) group in different response pathways of abiotic stress. Results showed significant expression levels of WRKY, WRKY53, WRKY33, WRKY1 and WRKY4 genes. An upregulation was observed in defense-related genes such as chitinase and defensin in roots by application EOs under pathogen condition. In conclusion, M. spicata and M. longifolia EOs can be used effectively to control this plant pathogen as sustainable and eco-friendly botanical fungicides.

Insight into Analysis of Essential Oil from Anisosciadium lanatum Boiss.-Chemical Composition, Molecular Docking, and Mitigation of Hepg2 Cancer Cells through Apoptotic Markers

Essential oils have been used in various traditional healing systems since ancient times worldwide, due to their diverse biological activities. Several studies have demonstrated their plethora of biological activities-including anti-cancer activity-in a number of cell lines. Anisosciadium lanatum Boiss. is a perennial aromatic herb. Traditionally, it is an edible safe herb with few studies exploring its importance. The current study aims to investigate the chemical composition of essential oil isolated from Anisosciadium lanatum using GC-MS, as well as report its anti-cancer potential and its mechanistic effect on HepG2 liver cancer cell lines, and conduct molecular docking studies. To achieve this, the essential oil was isolated using a Clevenger apparatus and analyzed using GC-MS. The cell viability of HepG2 liver cancer and normal fibroblast NIH-3T3 cell lines was assessed by MTT cytotoxicity assay. The effects of the essential oil on cell migration and invasion were assessed using wound healing and matrigel assays, respectively. The effect of the essential oil on migration and apoptotic-regulating mRNA and proteins was quantified using quantitative real-time PCR and Western blot techniques, respectively. Finally, computational docking tools were used to analyze in silico binding of major constituents from the essential oil against apoptotic and migration markers. A total of 38 components were identified and quantified. The essential oil demonstrated regulation of cell proliferation and cell viability in HepG2 liver cancer cells at a sub-lethal dose of 10 to 25 μg/mL, and expressed reductions of migration and invasion. The treatment with essential oil indicated mitigation of cancer activity by aborting the mRNA of pro-apoptotic markers such as BCL-2, CASPASE-3, CYP-1A1, and NFκB. The algorithm-based binding studies demonstrated that eucalyptol, nerol, camphor, and linalool have potent binding towards the anti-apoptotic protein BCL-2. On the other hand, camphor and eucalyptol showed potent binding towards the pro-apoptotic protein CASPASE-3. These findings highlight the effectiveness of the essential oil isolated from Anisosciadium lanatum to drive alleviation of HepG2 cancer cell progression by modulating apoptotic markers. Our findings suggest that Anisosciadium lanatum could be used as a phytotherapeutic anti-cancer agent, acting through the regulation of apoptotic markers. More well-designed in vivo trials are needed in order to verify the obtained results.

Can Plant Materials Be Valuable in the Treatment of Periodontal Diseases? Practical Review

Periodontal diseases are one of the most significant challenges in dental health. It is estimated that only a few percent of the worldwide population have entirely healthy teeth, and according to WHO, oral diseases may affect up to 3.5 billion people worldwide. One of the most serious oral diseases is periodontitis, an inflammatory disease affecting periodontal tissues, caused by pathogenic bacteria and environmental factors such as the ageing population, abuse of tobacco products, and lack of adequate oral hygiene due low public awareness. Plant materials are widely and successfully used in the management of many conditions, including periodontitis. Plant materials for periodontitis exhibit antibacterial, anti-inflammatory, antioxidant activities and affect the periodontium structure. Numerous studies demonstrate the advantages of phytotherapy for periodontitis relief and indicate the usefulness of Baikal skullcap root, Pomegranate fruit peel and root cortex, Tea leaves, Chamomile flowers, Magnolia bark, Blackberry leaves and fruits, Cranberry fruits and Lippia sidoides essential oil. This review aims to analyze the use and applicability of selected plant materials in periodontitis management since it is of paramount importance to evaluate the evidence of the traditionally used plant materials in light of continuously growing interest in phytotherapy and its adjuvant role in the treatment of periodontitis.

Chemical Constituents, In Vitro Antioxidant Activity and In Silico Study on NADPH Oxidase of Allium sativum L. (Garlic) Essential Oil

Allium sativum L., also known as garlic, is a perennial plant widely used as a spice and also considered a medicinal herb since antiquity. The aim of this study was to determine by gas chromatography-mass spectrometry (GC-MS) the chemical profile fingerprint of the essential oil (EO) of one accession of Peruvian A. sativum (garlic), to evaluate its antioxidant activity and an in- silico study on NADPH oxidase activity of the volatile phytoconstituents. The antioxidant activity was tested using DPPH and β-carotene assays. An in-silico study was carried out on NADPH oxidase (PDB ID: 2CDU), as was ADMET prediction. The results indicated that diallyl trisulfide (44.21%) is the major component of the EO, followed by diallyl disulfide (22.08%), allyl methyl trisulfide (9.72%), 2-vinyl-4H-1,3-dithiine (4.78%), and α-bisabolol (3.32%). Furthermore, the EO showed antioxidant activity against DPPH radical (IC50 = 124.60 ± 2.3 µg/mL) and β-carotene bleaching (IC50 = 328.51 ± 2.0). The best docking score on NADPH oxidase corresponds to α-bisabolol (ΔG = -10.62 kcal/mol), followed by 5-methyl-1,2,3,4-tetrathiane (ΔG = -9.33 kcal/mol). Additionally, the volatile components could be linked to the observed antioxidant activity, leading to potential inhibitors of NADPH oxidase.