Thymol Content Research Articles

Thymol-Loaded Polymeric Nanocapsules’ Repellent Activity on Nymphs of Rhipicephalus sanguineus Sensu Lato

Thymol-loaded polymeric nanocapsules were developed in this study to control volatilization and drug release for repellent application on Rhipicephalus sanguineus nymphs. Policaprolactone-loaded nanocapsules were prepared and characterized by diameter, PdI, zeta potential, pH, entrapment efficiency, and thymol content. Moreover, drug release, skin permeation profile, and repellent activity were evaluated. Nanocapsules showed a mean diameter of 195.7 ± 0.5 nm, a PdI of 0.20 ± 0.01, a zeta potential of −20.6 ± 0.3 mV, a pH of 4.7 ± 0.1, and an entrapment efficiency and a thymol content of 80.1 ± 0.1% and 97.9 ± 0.2%, respectively. The nanosystem progressively released 68.6 ± 2.3% of the thymol over 24 h, demonstrating that it can control drug release. Thymol-loaded nanocapsules showed less epidermis penetration upon skin application than pure thymol (control). Moreover, nanocapsules showed 60–70% repellency for 2 h against Rhipicephalus sanguineus nymphs. Thus, the nanocapsules proved to be a promising alternative for use as an arthropod repellent.

Seaweed extract and fulvic acid application affect the biomass performance, the essential oil yield and composition of Sicilian oregano grown in an organic agricultural system

Origanum vulgare ssp. hirtum is one of the taxa used as ‘oregano’ and is medicinal and aromatic plant (MAP) utilized worldwide in various sectors. Nowadays, agricultural systems are moving towards sustainable, organic, and environmentally friendly agricultural production and biostimulants have been used in recent years as a potential strategy. The objective of this research was to investigate the influence of seaweed extract based on Aschophyllum nodosum (AN) and fulvic acid (FA), applied with two different doses, on morphological parameters, fresh and dry yield, essential oil (EO) traits, total phenolic content (TPC), antioxidant activity (AA) and rosmarinic acid content (RAC) of organic oregano. Two-year experiment was conducted using a randomized complete block design with one main factor (foliar biostimulant) and 3 replicates. In AN- and FA-treated plants, increases in fresh biomass between 0.3 and 8.4 t ha−1 and in dry biomass between 0.5 and 3.0 t ha−1 were observed. The application of the lowest doses of fulvic acid (FA4) produced the highest EO contents (3.49 % and 3.46 %) and EO yields (73.3 and 97.4 kg ha−1) in both years. The application of the lowest doses of FA produced an increase (on average 4 %) in thymol content. Biostimulant application generated contrasting response, and, in some cases, a reduction in some chemical parameters compared with control plants. The findings of this study contribute to add novelty in cultivation of oregano. The application of low doses of AN and FA allows to increase yields and improve some qualities of the secondary metabolites from organic oregano.

Extension of shelf life of tomato (Solanum lycopersicum L.) by using a coating of polyhydroxybutyrate-carboxymethyl cellulose-pectin-thymol conjugate.

This study targets explicitly finding an alternative to petroleum-based plastic films that burden the environment, which is a high priority. Hence, polymeric films were prepared with carboxymethyl cellulose (CMC) (4%), pectin (2%), and polyhydroxybutyrate (PHB) (0.5%) with different concentrations of thymol (0.3%, 0.9%, 1.8%, 3%, and 5%) and glycerol as a plasticizer by solution casting technique. The prepared films were tested for mechanical, optical, antimicrobial, and antioxidant properties. Film F5 (CMC+P+PHB+0.9%thymol) showed an excellent tensile strength of 15MPa, Young's modulus of 395MPa, antioxidant activity (AA) (92%), rapid soil biodegradation (21 days), and strong antimicrobial activity against bacterial and fungal cultures such as Klebsiella pneumoniae, Staphylococcus aureus, Escherichia coli, Aspergillus niger, and Aspergillus flavus. The thymol content increase in films F6 (1.8%), F7 (3%), and F8 (5%) displayed a decrease in mechanical properties due to thymol's hydrophobicity. For shelf life studies on tomatoes, F2, a film without thymol (poor antimicrobial and antioxidant activities), F5 (film with superior mechanical, optical, antimicrobial, and antioxidant properties), and F7 (film with low mechanical properties) were selected. Film F5 coatings on tomato fruit enhanced the shelf life of up to 15 days by preventing weight loss, preserving firmness, and delaying changes in biochemical constituents like lycopene, phenols, and AA. Based on the mechanical, optical, antimicrobial, antioxidant, and shelf life results, the film F5 is suitable for active food packaging and preservation. PRACTICAL APPLICATION: The developed active biodegradable composite can be utilized as a coating to extend the shelf life of fruits and vegetables. These coatings are easy to produce and apply, offering a sustainable solution to reduce food waste. On an industrial scale, they can be applied to food products, ensuring longer freshness without any technical challenges.

Application of iron oxide nanoparticles improves growth and phytochemical constituents of in vitro cultured Carum copticum L.

Iron oxide nanoparticles (FeONPs) are widely used in various applications, such as biomedicine, environmental remediation, and agriculture. Moreover, FeONPs can affect the production of secondary metabolites in plants, which are compounds that have various biological and pharmacological activities. Therefore, in this study, the ajwain (Carum copticum L.) seeds were grown in MS medium containing different levels of FeONPs (0, 100, 200, and 400 mg l−1). After four weeks, the effects of FeONPs on growth, photosynthesis pigments, total phenolic, and anthocyanin content, activities of some antioxidant enzyme and secondary metabolites of ajwain) were investigated. The results showed that low levels of FeONPs (especially 200 mg l−1) increased fresh weight (231 %), total chlorophyll (49 %), total phenolics (259 %), anthocyanin content (110 %), as well as thymol (8 %) and γ-terpinene (16 %) content. Conversely, 400 mg l−1 FeONPs reduced root length (60 %) and fresh weight (64 %) was associated with a reduction in CAT activity, phenol (55 %), thymol (22 %), and γ-terpinene (18 %) content compared to ajwain treated with 200 mg l−1 FeONPs. This reduction was probably due to the increase in ROS caused by the low catalase enzyme activity and important essential oils compounds such as thymol and γ-terpinene. Thus, our results indicate that FeONPs at certain levels can be used as a new way for in vitro production of valuable essential oils and antioxidant compounds in ajwain.

Comparative Study of the Chemical Composition of Root, Stem and Leaf Essential Oils from Synedrella nodiflora (L.) Gaertn

This study aims at investigating the chemical composition of root, stem and leaf essential oils from Ivorian Synedrella nodiflora, with the root oil being described for the first time. Sixty, fifty-one and forty-nine constituents were, respectively identified in the root, stem and leaf oils using a combination of GC(RI), GC-MS and 13C-NMR analyses. They accounted for 95.6–97.3%, 92.6–97.6% and 93.3–98.8% of the total composition, respectively. The main components of the root oil samples were γ-curcumene, (E)-β-caryophyllene, α-curcumene and curcuphenyl acetate. Three stem oil samples (S1, S2a, S3) were dominated by myrcene and limonene, while the most abundant components of sample S2b were thymol, germacrene D and β-elemene. (E)-β-caryophyllene and germacrene D were the major compounds of the leaf oil. Hierarchical cluster and principal component statistical analyses were performed and confirmed that the location does not influence the chemical composition. Group I consisted of the seven leaf oil samples, group II consisted of four stem oil samples and group III consisted of three root oil samples. The root oil composition differed considerably from the stem and leaf oil composition due to the presence of curcumene derivatives as major constituents. The leaf oil showed significant amounts of (E)-β-caryophyllene and germacrene D, while the stem oil stood out for its high myrcene, limonene and thymol contents.

Unravelling the impact of drought and salt stresses on Thymus pannonicus: Morpho-physiological and biochemical insights

This research assesses the effects of drought and salt stresses applied individually or in combination on Thymus pannonicus, a resilient perennial herb native to the Pannonian vegetation region. Our experiment aimed to comprehensively evaluate morphological, physiological, and biochemical parameters of the thyme subjected to two levels of soil water capacity (SWC) - 70 % (control and salt stress) and 40 % (drought stress and combined stresses) - along with two salinity levels, 0 mM NaCl (control and drought stress) and 60 mM NaCl (salt stress and combined stresses). The plants exhibited significant responses to all the studied parameters under 40 % SWC in both treatments, demonstrating notable reductions in shoot and root parameters. In contrast, salt treatment at 60 mM had a minimal impact on growth. A stability in photosynthetic pigment composition was observed in all treatment, whereas a notable decrease (p < 0.05) in relative water content was seen in drought-stressed treatments compared to the to the control. Essential oil contents were higher in the control (0.91 ml/100g DW) but significantly declined (p < 0.05) under drought stress and combined stresses conditions (0.49 ml/100g DW and 0.53 ml/100g DW respectively). Particularly, the GC-MS analysis revealed a significant decrease (p < 0.05) in thymol and carvacrol content for the drought-stressed treatments. Substantial reductions were evident for the total polyphenol concentration and antioxidant capacity under the combined stress treatment, measuring 101.49 mg GAE/g DW and 106.57 AAE/g DW, respectively. Interestingly, the HPLC analysis indicated the highest levels of rosmarinic acid and caffeic acid in the drought-stressed treatment, while the lowest ones were recorded in the combined stress treatment. These findings indicated the responses of Thymus pannonicus to environmental stressors, emphasizing the need for further investigations for a comprehensive understanding of salinity effects.

Expression of the changes in essential oil components of Shirazi thyme (Zataria multiflora Boiss.) as affected by various drying methods

The purpose of this research was to investigate the impact of various drying techniques on the quality characteristics of Shirazi thyme (Zataria multiflora Boiss.) using a completely randomized design with three replications. The treatments included fresh samples, shade-drying (SHD), sun-drying (SD), oven and vacuum-drying (OD and VD) each at three different temperatures (45, 55, and 65 °C), and microwave-drying (MD) at three different power levels (200, 400, and 600 W). The results indicated that vacuum and oven-drying at 45 °C were effective in preserving valuable secondary metabolites compared to traditional drying methods. The essential oil (EO) content was lowest in the microwave-drying at 600 W (1.3 %), and highest in vacuum-drying at 45 °C (2.99 %). Vacuum-drying at 45 °C also produced the highest levels of carvacrol (72.5 %) and thymol (7.21 %) content, while the lowest levels were found in fresh samples. The main components in the EO were monoterpene hydrocarbons (11.47–27.33 %), oxygenated monoterpenes (74.81–86.9 %), and oxygenated sesquiterpenes (76.50–86.50 %). The results showed that the amount of sesquiterpene hydrocarbons and oxygenated monoterpenes were higher at low temperatures. Furthermore, the color parameters showed changes based on the drying methods, with vacuum-drying at 45 °C increasing the L* parameter (lightness), vacuum-drying at 65 °C increasing the a* parameter)brightness(, and oven-drying at 45 °C increasing the b* parameter)greenness). Understanding the different methods and operations of drying Shirazi thyme can provide valuable insight for its professional application and development in food and pharmaceutical industries.

Essential Oil of Fractionated Oregano as Motility Inhibitor of Bacteria Associated with Urinary Tract Infections.

In this research, several analyses were carried out on concentrated fractions of Mexican oregano essential oil (Poliomintha longiflora Gray) in order to determine its ability to inhibit the growth and the motility of Escherichia coli (swimming), Pseudomonas aeruginosa (swimming), and Proteus vulgaris (swarming); these Gram-negative bacteria associated with urinary tract infections are motile due to the presence of flagella, which is considered an important virulence factor that favors their motility when trying to reach the target organ and cause an infection. Also, the resistance pattern to antibiotics of each strain was determined. The results showed resistance pattern (8 out of 12 antibiotics tested) for P. aureginosa, while E. coli and P. vulgaris were resistant to 4 antibiotics out of the 12 tested. On the other hand, fractionated oregano caused an inhibition of growth and a reduction in motility, varying between fractions and among bacteria. Fraction 4 showed major growth reduction, with MBC values ranging from 0.002 to 23.7 mg/mL. Treatment with fractionated oregano (F1, F2, F3, F4) reduced the motility by 92-81% for P. vulgaris, 90-83% for E. coli, and 100-8.9% for P. aeruginosa. These results demonstrated a higher performance with a lower application dose due to its high content of Carvacrol and Thymol; unlike other concentrated fractions, this synergy of oxygenated monoterpenes may cause greater antimicrobial activity.

Evaluation of Different Drying Treatments with Respect to Essential Oil Components, Phenolic and Flavonoid Compounds, and Antioxidant Capacity of Ajowan (Trachyspermum ammi L.).

Ajowan (Trachyspermum ammi L.) is considered a valuable spice and medicinal herb. In this study, the essential oil content and composition of the aerial parts of ajowan were investigated under different drying treatments (sun, shade, oven at 45 °C, oven at 65 °C, microwave, and freeze drying). Moreover, the phenolic content, flavonoid content, and antioxidant capacity of samples were also assessed. Fresh samples produced the highest essential oil content (1.05%), followed by those treated under sun (0.7%) and shade drying (0.95%). Based on gas chromatography-mass spectrometry (GC-MS), thirty compounds were determined in which thymol (34.84-83.1%), carvacrol (0.15-32.36%), p-cymene (0.09-13.66%), and γ-terpinene (3.12-22.58%) were the most abundant. Among the drying methods, freeze drying revealed the highest thymol content, followed by drying in a 45 °C oven. The highest TPC (total phenolic content) and TFC (total flavonoid content) were obtained in the fresh sample (38.23 mg TAE g-1 dry weight (DW)) and in the sample oven-dried at 45 °C (7.3 mg QE g-1 DW), respectively. Based on the HPLC results, caffeic acid (18.04-21.32 mg/100 gDW) and ferulic acid (13.102-19.436 mg/100 g DW) were the most abundant phenolic acids, while among flavonoids, rutin constituted the highest amount (10.26-19.88 mg/100 gDW). Overall, freeze drying was the most promising method of drying for preserving the phenolic (TPC) and flavonoid (TFC) compounds and oil components.

Morphological and phenological characteristic, oil yield, quality and economics of Lemon bee balm (Monarda citriodora Cerv. ex-Lag) at diverse environment condition, India

Lemon bee balm (Monarda citriodora Cerv. ex-Lag) is a noble industrial medicinal and aromatic plant species, which is used as digestive, antifungal, anti-inflammatory and menstrual irregularity remedies in traditional medicine. It is a common source of thymol and other active constituents with recognized antimicrobial properties. A multilocation field trial was performed to evaluate essential oil (EO) yield stability, secondary metabolites and economic returns in eight diverse geographical environment conditions (GEC) in India. The secondary metabolites viz., essential oil content and oil yield were found to be highest in tropical and sub-tropical regions. The essential oil content was found to be higher in inflorescence part at all the experimental sites and found to be highest (0.85±0.21%) at BR-JALAUN. The highest EO yield (130.25±3.25 kg ha−1), net return (Rs. 1,22,125.00±245.21 ha−1) and benefit cost (B:C) ratio (2.67±0.17) was recorded at FFDC-KANNAUJ. The thymol content percentage was found to be highest on physiological maturity (>95% flowering) [PM] and on 75% flowering [FS-II] and it began to decline on seed formation stage at all the experimental sites. The significantly highest thymol content percentage was found on PM (86.65±3.91%) and on FS-II (84.21±3.78%) at TBR-JHANSI. On the basis of the gas chromatography and mass spectrophotometry analysis, twenty constituents were isolated. The inflorescence EO contains more thymol than the EO from leaves with stem which in turn was characterized by a higher content of p-cymene, γ-terpinene, carvacrol, α-phellandrene, α-pinene, myrcene, α-terpinene, citral and β-caryophyllene.

Volatile compositions and glandular trichomes of Zataria multiflora in different phenological stages under normal and drought stress conditions

BackgroundZataria multiflora Boiss. is a medicinal and aromatic plant from the Lamiaceae family. It is extensively used in Iranian traditional medicine, mostly as a replacement for Thyme species. This study was focused on the analysis of chemical composition and the distribution and types of trichomes of Z. multiflora grown under different conditions. Equilibrium headspace analysis in combination with GC-FID-MS was used to identify volatile compounds released by aerial parts of Z. multiflora in development stages of 50 and 100% flowering under normal and drought-stress conditions.ResultsThe main constituents were p-cymene (20.06–27.40%), γ-terpinene (12.44–16.93%), and α-pinene (6.91–16.58%) and thymol (8.52–9.99%). The highest content of p-cymene (27.40%) and thymol (9.99%) was observed in the 50% flowering stage at the 90% field capacity, while the maximum γ-terpinene (16.93%) content was recorded in the 100% flowering stage under normal conditions. Using the SEM method, it was found that peltate glandular and non-glandular trichomes are distributed on the surface of the leaf, stem, and outer side of the calyx. However, capitate trichomes only are detected on the stem and calyx in the 100% flowering and beginning of blooming stages, respectively. The type and structure of trichomes do not vary in different development stages, but they differ in density. The highest number of leaf peltate glandular trichomes was observed in the vegetative and beginning of blooming stages at 50% and 90% field capacity, respectively. Non-glandular trichomes of the stem were observed with high density in both normal and stress conditions, which are more densely in 90% field capacity.ConclusionsSince this plant has strong potential to be used in the food and pharmacological industries, this study provides valuable information for its cultivation and harvesting at specific phenological stages, depending on desired compounds and their concentrations.

Sources of fertilizers on the phytotechnical characteristics, oxidative stress and thymol production of Thymus vulgaris L.

The objective of this study was to assess the effects of different fertilizer sources on the phytotechnical characteristics, oxidative stress, and thymol production of Thymus vulgaris. The experiment was conducted in 3-dm³ pots containing soil:sand (2:1) + treatment (no fertilizer, organic fertilizer, or chemical fertilizer). The organic fertilizer was 8 kg m-2 of an equal mixture of bovine, goat, and quail manures. The variables assessed were leaf, stem, root, and total dry weights; chlorophyll and carotenoid contents; leaf nutrients; total polyphenols; total antioxidant capacity; oxygen radical absorption capacity; DPPH free radical scavenging activity; essential oil content; and thymol production, content, and yield. Organic fertilization significantly increased the variables assessed and reduced oxidative stress indicators. It resulted in gains in the dry weight of the plants and the accumulation of nutrients in dry leaves of T. vulgaris. For the quantitative parameters of the essential oil and thymol, organic fertilization was significantly higher than the other treatments, especially for thymol content and yield. T. vulgaris plants fertilized with organic fertilizer maximize their plant production and their yield of compounds of interest, such as thymol, possibly because these outputs indicate a balance between improved vegetative production and the elimination of reactive oxygen species.

An electrochemical sensor based on molecularly imprinted poly(o-phenylenediamine) for the detection of thymol

A molecularly imprinted electrochemical sensor was facilely fabricated for the detection of thymol (THY). o-Phenylenediamine (oPD) was used as the functional monomer and electropolymerized on the surface of the glassy carbon electrode (GCE) by using THY as the templates. After the THY templates were removed with 50 % (v/v) ethanol, imprinted cavities complementary to the templates were formed within the poly(o-phenylenediamine) (PoPD) films. The resultant molecularly imprinted PoPD/GCE (MI-PoPD/GCE) was used for the detection of THY, and a wide linear range from 0.5 to 100 μM with a low limit of detection (LOD) of 0.084 μM were obtained under the optimal conditions. The developed MI-PoPD/GCE also displays high selectivity, reproducibility and stability for THY detection. Finally, the content of THY in the real samples was accurately determined by the as-fabricated MI-PoPD/GCE, demonstrating its high practicability and reliability.

Phenolic Monoterpenes Conversion of Conobea scoparioides Essential Oil by Hydrotalcite Synthesized from Blast-Furnace Slag.

Conobea scoparioides (Plantaginaceae) is an herbaceous plant known as "pataqueira" that grows wild in seasonally wet areas of the Amazon region. It is used for aromatic baths and anti-protozoan remedies by the Brazilian Amazon native people. The main volatile compounds identified in the essential oil of "Pataqueira" were the phenolic monoterpenes thymol and thymol methyl ether and their precursors, the monoterpene hydrocarbons α-phellandrene and p-cymene. A hydrotalcite synthesized from blast-furnace slag exhibited a 3:2 (Mg/Al) molar ratio, and this layered double hydroxide (LDH) was evaluated as a catalyst in converting the main monoterpenes of the "Pataqueira" oil. This action significantly increased the thymol content, from 41% to 95%, associated with the percentual reduction in other main components, such as thymol methyl ether, α-phellandrene, and p-cymene. The LDH reaction showed a strong tendency towards producing hydroxylated derivatives, and its behavior was similar to the hypothetical plant biosynthetic pathway, which leads to the production of the monoterpenes of "Pataqueira" oil. Thymol and its derivatives are potent antiseptics applied in pharmaceutical and hygienic products as antibacterial, antifungal, and antioxidant properties, among others. The present work reports a natural source with a high thymol content in aromatic plants from the Amazon, with evident economic value.

Effect of gamma rays on the essential oil and biochemical characteristics of the Satureja mutica Fisch & C. A. Mey.

There are 16 species in the genusSaturejaL. (Lamiaceae), of which10are native.This research aimed to investigate the effect of gamma rays and storage conditions and duration on the percentage and components of the essential oil and some biochemical characteristics ofSatureja muticaFisch & C.A. Mey at the Research Institute of Forests and Rangelands.Plants were collectedat the full floweringstageand exposed todifferent doses of gamma rays (0, 2.5, 5, 7.5, and10kGy)at the Atomic EnergyOrganization, Iran.The samples were keptin a refrigerator (4°C)and in the shade(25 ± 2°C) for 0, 120, and 240h. This experiment was performedin acompletely randomizeddesign. Essential oil extraction was done by water distillationfor2h. The composition of their essential oil components was identified usingGC and GC/MS.Somebiochemicaltraits, including phenol content, antioxidant capacity, and carbohydrate content, were measured. The results indicated that irradiation on the percentage of essential oil showeda statistically significant difference. In addition, theinteraction effect of irradiation × storage conditions, irradiation × duration of storage, on the percentage of essential oilwassignificant. According to a comparison of the means, 2.5kGy irradiation produced the highest percentage of essential oil (0.4%); in contrast, a significant decreasewas detectedin components with 7.5 and 10kGy irradiation. It was observed thatthepercentage of some essential oil compounds decreasedwith the gamma-ray intensity increase.2.5kGy of gamma rays and shade storage conditions for 240h led to the highest content of p-cymene and carvacrol. Nevertheless,the highest thymol content wasobtained under refrigeration conditions without irradiation. The maximum phenol content and antioxidant capacity were obtained when the plants were irradiated with 2.5 and7.5kGy gamma rays.However,the maximum carbohydrate ratewas observed in non-irradiated plants.It was concluded that low-intensity gamma rays could improve the percentage of essential oil and main components like p-cymene and carvacrol in S. mutica Fisch & C.A. Mey.

Aqueous dispersions of oleic acid nanodroplets for thymol encapsulation

This study focuses on the use of oleic acid to disperse thymol as nanodroplets, stabilized by a mixture of alkylpolyglucoside and lecithin, in an aqueous environment. This approach aims to develop innovative platforms for the encapsulation and release of poorly water-soluble molecules such as thymol, useful for drug delivery and insecticide systems. The results highlight the critical role of controlling the content and concentration of the oil phase (thymol-oleic acid mixture) in achieving optimal thymol dispersion and nanodispersion stability. The interplay between the ability of oleic acid to inhibit thymol crystallization and the maximum dispersible oil amount is crucial. It affects the dispersion of thymol within the nanodroplets and influences coalescence and Ostwald ripening phenomena. The balance between oleic acid and thymol content is key: while oleic acid stabilizes dispersions, higher thymol content increases droplet size, potentially triggering destabilization. The uneven distribution of thymol within the droplets, revealed by fluorescence spectroscopy, suggests that up to three different chemical environments exist. This investigation may pave the way for the development of efficient platforms to improve access to biologically relevant, poorly soluble molecules.

Study of antimicrobial properties of liquid plaster containing of oregano essential oil (Origanum vulgare L.)

Treatment of wounds resulting from combat injuries is complicated by the addition of a secondary infection caused by multi-resistant bacteria. The liquid patch appears to be a promising formulation for wound therapy. The antimicrobial effect of essential oils is manifested due to the content of numerous components that interfere with the proliferation and formation of bacterial resistance. The aim of the work was to substantiate the choice of Origanum vulgare L. essential oil as the main active ingredient of a liquid patch with antimicrobial action, confirm the composition of the essential oil and study the antimicrobial properties of the model drug. The object of the study were model samples of a liquid patch with an experimentally developed film-forming system. Various concentrations of commercial essential oil of O. vulgare L., the composition of which was confirmed by GB/MS analysis, were used as the active pharmaceutical ingredient. Antimicrobial activity was studied by direct contact method using microbial culture tests. The use of liquid patch in the treatment of skin lesions of various etiologies, including combat wounds, is justified. The variability of the composition of the essential oil of O. vulgare L. depending on the subspecies, chemotype and growth conditions of the plant is discussed. The component composition of a commercial sample of O. vulgare L. essential oil, confirmed by GC/MS analysis, is considered. 11 components declared by the manufacturer were found to be completely identical, in particular, carvacrol, thymol, and monoterpene hydrocarbons. The other 11 compounds discovered were monoterpenoids and sesquiterpenoids. Research has confirmed the feasibility of using O. vulgare L. essential oil, thymol-carvacrol chemotype, as an antimicrobial component. The dependence of the antimicrobial activity of model samples of liquid plaster on the concentration of Oregano essential oil was established. The essential oil of O. vulgare L. has a variable composition and requires mandatory control of the content of thymol and carvacrol, which inhibit the growth of the studied microorganisms. The antimicrobial effect of a liquid patch containing essential oil of O. vulgare L. at a concentration of 0.15 mg/ml is manifested against test cultures of microorganisms – Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis.

Synthetic polyploidization induces enhanced phytochemical profile and biological activities in Thymus vulgaris L. essential oil

Essential oil from Thymus vulgaris L. has valuable therapeutic potential that is highly desired in pharmaceutical, food, and cosmetic industries. Considering these advantages and the rising market demand, induced polyploids were obtained using oryzalin to enhance essential oil yield. However, their therapeutic values were unexplored. So, this study aims to assess the phytochemical content, and antimicrobial, antioxidant, and anti-inflammatory activities of tetraploid and diploid thyme essential oils. Induced tetraploids had 41.11% higher essential oil yield with enhanced thymol and γ-terpinene content than diploid. Tetraploids exhibited higher antibacterial activity against all tested microorganisms. Similarly, in DPPH radical scavenging assay tetraploid essential oil was more potent with half-maximal inhibitory doses (IC50) of 180.03 µg/mL (40.05 µg TE/mg) than diploid with IC50 > 512 µg/mL (12.68 µg TE/mg). Tetraploids exhibited more effective inhibition of in vitro catalytic activity of pro-inflammatory enzyme cyclooxygenase-2 (COX-2) than diploids at 50 µg/mL concentration. Furthermore, molecular docking revealed higher binding affinity of thymol and γ-terpinene towards tested protein receptors, which explained enhanced bioactivity of tetraploid essential oil. In conclusion, these results suggest that synthetic polyploidization using oryzalin could effectively enhance the quality and quantity of secondary metabolites and can develop more efficient essential oil-based commercial products using this induced genotype.

RELATIONSHIP BETWEEN BIOCHEMICAL INDICATORS AND PHENOTYPICAL CHARACTERISTICS OF THYME (THYMUS VULGARIS L.)

Introduction. Thyme (Thymus vulgaris L.) is a sought-after medicinal crop, the raw materials of which are included in the Pharmacopoeias of several countries and are widely used in scientific medicine. Due to the presence of strong intraspecific diversity in thyme, it seems interesting to identify phenotypic characteristics that most likely indicate the presence of certain pharmacologically significant compounds. The presence of such information will allow targeted selection both in natural populations and during the hybridization of cultivars and the development of new varieties. The purpose of the work was to identify phenotypic traits indicating a high content of essential oil and thymol in thyme, the amount of phenolic compounds, flavonoids and tannins. Material and methods. Samples and varieties of thyme from different geographical origins were selected as objects. Biometric, anatomical indicators and yield were determined in the flowering phase. The essential oil content was determined by Clevenger hydrodistillation method. Component composition was determined by gas chromatography. The amount of phenolic compounds and tannins according to the Folin-Ciocalteu method in aqueous-alcoholic extract calculated as gallic acid. The determination of flavonoids in the aqueous-alcoholic extract was carried out using the spectrophotometryс method calculated as rutin. Results. As a result of the research, no signs were found indicating a high content of essential oil. Flavonoid content calculated as rutin had a negative correlation (−0.72) with stomatal density. A negative relationship was noted between the intensity of coloring of the pistil and anthers and the content of the total phenolic compounds calculated as gallic acid (0.71 and 0.72, respectively). Large stomata on both the underside and upper side of the leaf may indicate a high tannin content (0.8 and 0.88). All studied components of common thyme belonged to the thymol type, and the content of this component ranged from 37.6 to 80.8%. An increased content of thymol in essential oil is observed such signs as an elongated leaf shape (leaf index R = 0.78), lack of downward curling of the edges of the leaf blade (R = –0.78) and pronounced veins on the underside of the leaf (R = 0.92). Large stomata on the lower epidermis also indicate an increased proportion of thymol in the essential oil (R = 0.78). When analyzing the interdependence between the content of the main components of essential oil, it was noted that there is a close negative correlation between the content of p-cymene and thymol (R = –0.91) and carvacrol (R = –0.88). Conclusion. As a result of the research, phenotypic and anatomical characteristics were identified that make it possible to diagnose promising samples of common thyme, which will help speed up the selection process.

Carvacrol and Thymol Content Affects the Antioxidant and Antibacterial Activity of Origanum compactum and Thymus zygis Essential Oils.

Essential oils are of great interest due to their potent pharmaceutical and biological activities. In this study, essential oils extracted from Origanum compactum and Thymus zygis originating from the Middle Atlas of Morocco were investigated. Their chemical compositions were analyzed using gas chromatography and mass spectrometry, while the assessment of the trapping power of the radical (DPPH: 1,1-diphenyl-2-picrylhydrazyl) and the reducing antioxidant potential of ferric ions (FRAP: Ferric Reducing Antioxidant Power) were performed in order to evaluate the antioxidant activity. Their antibacterial potency was tested against six bacterial strains through the disk diffusion method. The chromatography analyses of the extracted essential oils highlighted the presence of two main components, namely carvacrol at 75.70% in O. compactum and thymol at 40.67% in T. zygis. The antioxidant activity tests showed that both essential oils demonstrated a significant antioxidant activity comparable to the positive control (e.g., ascorbic acid). The antibacterial activity results showed a strong antimicrobial effect for both essential oils, compared to synthetic antibiotics. This study affirms the presence of bioactive components with interesting antioxidant and antibacterial activities in the essential oils extracted from Origanum compactum and Thymus zygis, which could find several applications in the food and pharmaceutical industries through the substitution of synthetic antioxidants and antibiotics.