Composition, Antifungal, Phytotoxic, and Insecticidal Activities of Thymus kotschyanus Essential Oil

Discovery of Novel Cyclobutyl Oxime Ester Derivatives Containing an α,β-Unsaturated Carbonyl Moiety as Potential Mitochondrial Toxins

As part of continuous work to explore novel and efficient fungicides originating from natural products, a series of cyclobutyl oxime ester derivatives containing an α,β-unsaturated carbonyl moiety were designed and synthesized. In line with the primary evaluation of the inhibitory effect on common pathogenic fungi causing crop failure, a systematic study on the antifungal activity of target compounds against Rhizoctonia solani was carried out. Most target compounds exhibited satisfactory antifungal activity, and 10 of them were superior to the positive control trifloxystrobin. The most notable median effective concentration (EC50) of compound 6b was 1.70 μg/mL, which was considerable for an intensive study. The control efficacy of compound 6b on potted rice against R. solani was superior to trifloxystrobin at identical concentration. The mycelial morphology and cell membrane permeability of the treated fungi were disrupted, and the meaningful enzyme activities of SDH and POD were also restrained. The reactive oxygen species, nuclear morphology, and mitochondrial membrane potential of the treated hypha reflected an apparent difference compared with the normal morphology, which represented mitochondrial function damage. In addition, chemical features essential for the activity and docking mode within the compound and cytochrome bc1 complex were accessed by computer-aided technology. This study provided insights into the development of new green and efficient fungicides targeting the mitochondria.

The influence of climate change on the future distribution of two Thymus species in Iran: MaxEnt model-based prediction

Within a few decades, the species habitat was reshaped at an alarming rate followed by climate change, leading to mass extinction, especially for sensitive species. Species distribution models (SDMs), which estimate both present and future species distribution, have been extensively developed to investigate the impacts of climate change on species distribution and assess habitat suitability. In the West Asia essential oils of T. daenensis and T. kotschyanus include high amounts of thymol and carvacrol and are commonly used as herbal tea, spice, flavoring agents and medicinal plants. Therefore, this study aimed to model these Thymus species in Iran using the MaxEnt model under two representative concentration pathways (RCP 4.5 and RCP 8.5) for the years 2050 and 2070. The findings revealed that the mean temperature of the warmest quarter (bio10) was the most significant variable affecting the distribution of T. daenensis. In the case of T. kotschyanus, slope percentage was the primary influencing factor. The MaxEnt modeling also demonstrated excellent performance, as indicated by all the Area Under the Curve (AUC) values exceeding 0.9. Moreover, based on the projections, the two mentioned species are expected to undergo negative area changes in the coming years. These results can serve as a valuable achievement for developing adaptive management strategies aimed at enhancing protection and sustainable utilization in the context of global climate change.

Tailoring and optimization of a honey-based nanoemulgel loaded with an itraconazole-thyme oil nanoemulsion for oral candidiasis

The use of essential oil-based nanoemulsions (NEs) has been the subject of extensive research on a variety of conditions affecting the oral cavity. NEs are delivery methods that improve the solubility and distribution of lipid medicines to the intended areas. Because of their antibacterial and antifungal properties, itraconazole and thyme oil-based self-nanoemulsifying drug delivery systems (ItZ-ThO-SNEDDS) were created to protect oral health against oral microorganisms. The ItZ-ThO-SNEDDS were created utilizing an extreme verices mixture design, and varying concentrations of ThO (10% and 25%), labrasol (40% and 70%), and transcutol (20% and 40%) were used. The ItZ-ThO-SNEDDS had droplet sizes of less than 250 nm, a drug-loading efficiency of up to 64%, and a fungal growth inhibition zone of up to 20 mm. The accepted design was used to obtain the ideal formulation, which contained ThO in the amount of 0.18 g/ml, labrasol 0.62 g/ml, and transcutol 0.2 g/ml. The best ItZ-ThO-SNEDDS formulation was incorporated into a honey-based gel, which demonstrated improved release of ItZ in vitro and improved transbuccal permeation ex vivo. In addition, when compared with various formulations tested in rats, the optimized loaded emulgel decreased the ulcer index. This study therefore demonstrated that the ItZ-ThO-SNEDDS could offer an effective defense against oral diseases caused by microbial infections.

The component of the Chamaecyparis obtusa essential oil and insecticidal activity against Tribolium castaneum (Herbst)

Tribolium castaneum (Herbst) is a worldwide grain storage pest controlled by chemical control methods of phosphine fumigation, which results in many hazards, damages human health, makes pests resistant to pesticides, and pollutes the environment. In recent years, the popularity of botanical insecticides has continued to rise, and plant essential oils (EO) are considered potential alternatives for developing insecticides. In the current study, we selected the Chamaecyparis obtusa EO to determine its insecticidal effects and component analysis on T. castaneum. Through gas chromatography-ion mobility spectrometry (GC-IMS) technology, cedrol was the most obvious compound in the signal peak of the volatile components detected in the C. obtusa EO. The results of the bioassay showed that the C. obtusa EO had certain contact activity against T. castaneum, and the LD50 was 52.54 μg/adult. At three concentrations (0.41,1.62, 2.83 uL/cm2), the repellent rates of C. obtusa EO against T. castaneum were all above 80% at 15, 30, 60, and 120 min, respectively, indicating that the repellent effect was strong. Meanwhile, the C. obtusa EO exhibited fumigant toxicity against T. castaneum with LC50 values of 7.09 μg/L air. In addition, C. obtusa EO significantly increased the activity of AChE, CarE, POD, CAT, T-SOD, and chitinase in T. castaneum. Finally, the mechanism of C. obtusa EO on T. castaneum adults was explored based on transcriptome sequencing. We found that the DEGs focused on the chitin metabolic process and some aging genes in T. castaneum. Therefore, C. obtusa EO could be used as potential eco-friendly candidates for stored grain pest management.

Emerging Insights into the Applicability of Essential Oils in the Management of Acne Vulgaris

The occurrence of pustules, comedones, nodules, and cysts defines acne vulgaris, a prevalent chronic inflammatory dermatological condition. In the past few decades, essential oils extracted from varied natural sources have acquired recognition due to their potential medicinal applications in acne therapy. However, there is not yet sufficient medical data to fully characterize this interaction. Multiple factors contribute to the development of acne vulgaris, including excessive sebaceous production, inflammatory processes, hyperkeratinization, and infection with Cutibacterium acnes. Essential oils, including oregano, lavender, lemon grass, myrtle, lemon, thyme, eucalyptus, rosemary, and tea tree, have been found to possess anti-inflammatory, antioxidant, and antimicrobial properties, which may target the multifactorial causes of acne. Analytical methods for determining antioxidant potential (i.e., total phenolic content, diphenyl-1-picrylhydrazyl free radical scavenging assay, reducing power assay, ferrous ion chelating activity, thiobarbituric acid reactive species assay, β-carotene bleaching assay, etc.) are essential for the evaluation of these essential oils, and their method optimization is crucial. Further studies could include the development of novel acne treatments incorporating essential oils and an assessment of their efficacy in large clinical trials. In addition, further research is necessary to ascertain the mechanisms of action of essential oils and their optimal doses and safety profiles for optimal implementation in the management of acne vulgaris.

Chemical composition, pesticidal activities and in-silico investigation of Hedychium spicatum Sm. chloroform extract

The present study aimed to identify the bioactive constituents in the chloroform extract of H. spicatum rhizomes (HS-RCLE), further evaluated for its in-vitro pesticidal activities validating via molecular docking techniques. GC/MS analysis of HS-RCLE identified 14 compounds contributing 84.1 % of the total composition. The extract was dominated by oxygenated sesquiterpenes (43.1 %) with curcumenone (25.2 %) and coronarin E (14.8 %) as the major compounds. The extract recorded 89.4 % egg hatchability inhibition and 82.6 % immobility of Meloidogyne incognita, 66.7 % insecticidal activity on Spodoptera litura, 100 % phytotoxic activity on Raphanus raphanistrum seeds, and 74.7 % anti-fungal activity on Curvularia lunata at the respective highest dose studied. The biological activities were furthermore validated by using docking studies on certain proteins/enzymes namely acetylcholinesterase (PBD ID: IC2O), carboxylesterase (PDB ID: 1CI8), acetohydroxyacid synthase (PBD ID: 1YHZ) and trihydroxy naphthalene reductase (PBD ID: 3HNR). The bioactivity of the major constituents of the extract was predicted with the help of in silico PASS studies. HS-RCLE was observed to be a viable alternative source of natural pesticidal agents and paves the way for further studies on its mechanistic approaches and field trials to ascertain its pesticidal studies.

Six Spain Thymus essential oils composition analysis and their in vitro and in silico study against Streptococcus mutans

BACKGROUND

Streptococcus mutans is a well-known oral pathogen that plays a critical role in the development of dental caries. Many studies have been directed to discover the chemical compounds present in natural products to inhibit the growth and biofilm formation activity of S. mutans. Thymus essential oils exhibit good inhibition on the growth and pathogenesis of S. mutans. However, details about the active compounds in Thymus essential oil and the inhibition mechanism still remain unclear. The aim of this study was to investigate the antimicrobial activity of 6 Thymus species (Three samples of Thymus vulgaris, two samples of Thymus zygis, and one sample of Thymus satureioides essential oils) on S. mutans, to identify the potential active components, and to reveal the underlying mechanism.

METHODS

The composition of Thymus essential oils was analyzed by gas chromatography-mass spectrometry. And its antibacterial effect was evaluated based on the bacterial growth, acid production, biofilm formation and genetic expression of virulence factors by S. mutans. Potential active components of the Thymus essential oil were identified using molecular docking and correlation analysis.

RESULTS

GC-MS analysis showed that the major components in the 6 Spain Thymus essential oils were linalool, α-terpineol, p-cymene, thymol and carvacrol. MIC and MBC analysis showed that 3 Thymus essential oils showed very sensitive antimicrobial activity, and were chosen for further analysis. The 3 Thymus essential oil exhibited a significant inhibitory effect on acid production, adherence and biofilm formation of S. mutans and the expression of virulence genes, such as brpA, gbpB, gtfB, gtfC, gtfD, vicR, spaP and relA. Correlation analysis showed that phenolic components, such as carvacrol and thymol, were positively related to DIZ value, which suggests that they are the potential antimicrobial components. Molecular docking between the Thymus essential oil components and virulence proteins also found that carvacrol and thymol exhibited strong binding affinity with functional domains of virulence genes.

CONCLUSIONS

Thymus essential oil showed significant inhibition against the growth and pathogenesis of S. mutans depending on their composition and concentration. And phenolic compounds, such as carvacrol and thymol, are the major active components. Thymus essential oil could be used in oral healthcare products as a potential anti-caries ingredient.

Phytochemical and biological activities of some Iranian medicinal plants

CONTEXT

Due to adverse effects of synthetic compounds, there is a growing interest in utilization of plant-derived natural products in the pharmaceutical and food industries. Iranian endemic medicinal plants widely used in traditional practice have attracted much attention as antibacterial and antioxidant agents.

OBJECTIVE

This review attempts to compile the accessible scientific research pertained to phytochemical compounds, antibacterial and antioxidant effects of essential oils obtained from some of the most widely used and distributed medicinal plants in Iran.

METHODS

This review has been compiled using references via reliable databases (Google Scholar, SID and Science Direct) from 2010 to 2020. This literature review was limited to references published in English and Persian languages.

RESULTS

Based on studies heretofore carried out, essential oils isolated from mentioned medicinal plants exhibited strong antioxidant activity which is attributed to their main phytochemical compounds; thymol, carvacrol, p-cymene and γ-terpinene. In addition, the antibacterial activities of essential oils of most plant species from Apiaceae and Asteraceae families were more susceptible against Gram-positive bacteria; Staphylococcus aureus and Bacillus cereus than Gram-negative bacteria; however, essential oils of other studied plant species manifested similar behaviours against both Gram-positive and -negative bacteria.

CONCLUSIONS

As there is rich ethnobotanical knowledge behind Iranian endemic medicinal plants, further scientific research is required to prove their safety and efficacy. This review revealed that there are numerous valuable medicinal plants adoptable in food and pharmaceutical industries in the near future.

Plant as an Alternative Source of Antifungals against Aspergillus Infections: A Review

Aspergillus species consists of a group of opportunistic fungi that is virulent when the immunity of the host is compromised. Among the various species, Aspergillus fumigatus is the most prevalent species. However, the prevalence of fungal infections caused by non-fumigatus Aspergillus has been increasing. Polyenes, echinocandins and azoles are the three main classes of antifungal agents being used for the treatment of aspergillosis. Nevertheless, the incidence of resistance towards these three classes has been rising over the years among several Aspergillus spp. The side effects associated with these conventional antifungal agents have also limited their usage. This urges the need for the discovery of a safe and effective antifungal agent, which presents a major challenge in medicine today. Plants present a rich source of bioactive molecules which have been proven effective against a wide range of infections and conditions. Therefore, this present review intends to examine the current literature available regarding the efficacy and mechanism of action of plant extracts and their compounds against Aspergillus spp. In addition, novel drug delivery systems of plant extracts against Aspergillus spp. were also included in this review.

Natural Antimicrobials: A Clean Label Strategy to Improve the Shelf Life and Safety of Reformulated Meat Products

Meat is a nutrient-rich matrix for human consumption. However, it is also a suitable environment for the proliferation of both spoilage and pathogenic microorganisms. The growing demand to develop healthy and nutritious meat products with low fat, low salt and reduced additives and achieving sanitary qualities has led to the replacement of the use of synthetic preservatives with natural-origin compounds. However, the reformulation process that reduces the content of several important ingredients (salt, curing salts, etc.), which inhibit the growth of multiple microorganisms, greatly compromises the stability and safety of meat products, thus posing a great risk to consumer health. To avoid this potential growth of spoiling and/or pathogenic microorganisms, numerous molecules, including organic acids and their salts; plant-derived compounds, such as extracts or essential oils; bacteriocins; and edible coatings are being investigated for their antimicrobial activity. This review presents some important compounds that have great potential to be used as natural antimicrobials in reformulated meat products.

Intracellular production of reactive oxygen species and a DAF-FM-related compound in Aspergillus fumigatus in response to antifungal agent exposure

Fungi are ubiquitously present in our living environment and are responsible for crop and infectious diseases. Developing new antifungal agents is constantly needed for their effective control. Here, we investigated fungal cellular responses to an array of antifungal compounds, including plant- and bacteria-derived antifungal compounds. The pathogenic fungus Aspergillus fumigatus generated reactive oxygen species in its hyphae after exposure to the antifungal compounds thymol, farnesol, citral, nerol, salicylic acid, phenazine-1-carbonic acid, and pyocyanin, as well as under oxidative and high-temperature stress conditions. The production of nitric oxide (NO) was determined using diaminofluorescein-FM diacetate (DAF-FM DA) and occurred in response to antifungal compounds and stress conditions. The application of reactive oxygen species or NO scavengers partly suppressed the inhibitory effects of farnesol on germination. However, NO production was not detected in the hyphae using the Greiss method. An LC/MS analysis also failed to detect DAF-FM-T, a theoretical product derived from DAF-FM DA and NO, in the hyphae after antifungal treatments. Thus, the cellular state after exposure to antifungal agents may be more complex than previously believed, and the role of NO in fungal cells needs to be investigated further.

Evaluation of the efficacy of Thymus kotschyanus extract as an additive treatment in patients with ulcerative colitis: a randomized double-blind placebo-controlled trial

BACKGROUND

Ulcerative colitis (UC) is one of the chronic diseases which is increasing in prevalence and patients suffer from illness flare-ups. UC standard regimen treatment has various side effects besides the efficacy, so there is an interest in administering complementary medicine to reduce adverse effects and increase the efficacy, as well. The aim of this study was to evaluate the efficacy and anti-inflammatory effect of Thymus kotschyanus as an additive treatment in a randomized double-blind placebo-controlled trial of UC patients.

METHODS

Thirty UC out-patients with mesalazine regimen treatment that fulfilled the inclusion criteria were participated in a 12 week trial and were randomly chosen for the treatment and control group. Fifteen patients were administered a placebo as a control and 15 patients were received Thymus kotschyanus extract by a dose of 0.5 g in a day in the treatment group. Laboratory tests were performed at baseline and week 12. The primary outcome was a reduction in fecal calprotectin as the main intestine inflammatory marker. Likewise, reduction in SCCAI, SIDBQ, and SEO indices were considered as secondary aims.

RESULTS

Fecal calprotectin was decreased by 54.74% in the treatment group, as compared with the placebo group at week 12 (p = 0.02). A significant reduction in SCCAI was also shown between the two study groups (p = 0.01). Thymus kotschyanus extract was safe and no severe side effects were reported.

CONCLUSION

Administration of Thymus kotschyanus revealed improvement in UC symptoms by the intestinal anti-inflammation effect of the plant and could be suggested as a potential additive treatment in UC patients. The study protocol has been registered under the identification code: IRCT20200406046965N2.

Chemical Profiles and Insecticidal Potential of Essential Oils Isolated from Four Thymus Species against Rhyzopertha dominica (F.)

Although chemical pesticides have been efficiently used to manage insect pest, their overuse has led to environmental contamination and threats to human health, enticing researchers to introduce eco-friendly and effective agents. In this study, the insecticidal effectiveness of essential oils isolated from Thymus species, including T. eriocalyx, T. kotschyanus, T. fallax, and T. vulgaris, was evaluated against the adults of Rhyzopertha dominica. The terpenes p-cymene, 1,8-cineole, linalool, α-terpineol, and carvacrol were the prominent compounds in the hydrodistilled essential oils. All essential oils produced significant fumigant at 24, 48, and 72-exposure times. The energy reserves protein by all essential oils, glycogen by T. kotschyanus and T. vulgaris, and lipid by T. fallax and T. vulgaris were significantly decreased compared to control. All essential oils except T. vulgaris affected the amylolytic and proteolytic activity of the pest. The pest increased the α- and β-esterase enzyme activity in response to the essential oils. Nutritional indices of adults were also affected by essential oils, in which feeding deterrence index was calculated from 20.41% to 61.11%. Accordingly, based on lethal and extensive sub-lethal insecticidal activities, T. eriocalyx, T. kotschyanus, T. fallax, and T. vulgaris essential oils can be considered as efficient agents for R. dominica management.

Allelopathic Properties of Lamiaceae Species: Prospects and Challenges to Use in Agriculture

Herbicide resistance due to the increasing reliance on herbicides is a near-term challenge for the world’s agriculture. This has led to a desire to develop new herbicides with a novel mode of action, to address resistance in weed species. Lamiaceae, a large dicotyledonous plant family, is very well known for the multitudinous pharmacological and toxicological properties of its member species. Moreover, many species of this family are significant for their allelopathic activity in natural and laboratory settings. Thus, plants in Lamiaceae have the potential to be sources of alternative herbicides. However, gaps in our knowledge need to be addressed prior to adopting these allelopathic activities in agriculture. Therefore, we review the existing state of knowledge about the Lamiaceae family, the reported allelopathic properties of plant extracts, and their isolated allelochemicals under laboratory, greenhouse, and field conditions. In addition, we offer a perspective on existing challenges and future opportunities for adopting the allelopathic properties of Lamiaceae plant species for green agriculture.

Eco-friendly 'ochratoxin A' control in stored licorice roots - quality assurance perspective

According to toxicity data, ochratoxin A (OTA) is the second most important mycotoxin and is produced by Aspergillus and Penicillium. As a natural antifungal agent, clove essential oil (CEO) is a substance generally recognised as safe (GRAS) and shows strong activity against fungal pathogens. Here, we aimed to investigate the control efficacy of CEO in nano-emulsions (CEN) against OTA production in licorice roots and rhizomes during storage. The experiments were performed under simulated conditions of all four seasons (i.e. Spring, Summer, Autumn and Winter). Relative humidity (RH) and temperature were simulated in desiccators along with various salt solutions in incubators. Fresh licorice roots were immersed in CEN at various concentrations (150, 300, 600, 1200 and 2400 µl/l). Before utilising the nano-emulsions, we measured their polydispersity index and mean droplet size by the dynamic light scattering (DLS) technique. Also, the chemical composition of the CEO was determined using GC and GC-MS analyses. Sampling was carried out to monitor OTA once every five days. The samples were dried immediately and analysed by high-performance liquid chromatography (HPLC). Results showed that various concentrations of CEN inhibited the growth of fungi and OTA production. The most effective CEN concentrations were 1200 and 2400 µl/l, which reduced OTA production to 19 and 20 ppb under Winter and Autumn conditions, respectively. These results suggest an effective eco-friendly method for the storage of licorice to reduce postharvest fungal decay.

Pesticidal Activity and Mode of Action of Monoterpenes

Synthetic pesticides are often associated with issues such as pest resistance, persistent residue, nontarget toxicity, and environmental issues. Therefore, the research and development of novel, safe, and effective pesticides has become a focus in pesticide discovery. Monoterpenes are secondary plant metabolites that commonly have multiple action targets and have been used in aromatherapy, alternative medicine, and food industries. Some are highly potent and stereoselective. They can potentially be botanical pesticides and serve as lead candidates for the design and synthesis of new monoterpenoid pesticides for agricultural applications. This article reviews publications and patents found in SciFinder Scholar between 2000 and May 2021 on monoterpenes and mainly focuses on pesticidal activities of frequently studied monoterpenes and their modes of action. The presented information and our views are hopefully useful for the development of monoterpenes as biopesticides and monoterpenoid pesticides.

Biocontrol Potential of Essential Oils in Organic Horticulture Systems: From Farm to Fork

In recent decades, increasing attention has been paid to food safety and organic horticulture. Thus, people are looking for natural products to manage plant diseases, pests, and weeds. Essential oils (EOs) or EO-based products are potentially promising candidates for biocontrol agents due to their safe, bioactive, biodegradable, ecologically, and economically viable properties. Born of necessity or commercial interest to satisfy market demand for natural products, this emerging technology is highly anticipated, but its application has been limited without the benefit of a thorough analysis of the scientific evidence on efficacy, scope, and mechanism of action. This review covers the uses of EOs as broad-spectrum biocontrol agents in both preharvest and postharvest systems. The known functions of EOs in suppressing fungi, bacteria, viruses, pests, and weeds are briefly summarized. Related results and possible modes of action from recent research are listed. The weaknesses of applying EOs are also discussed, such as high volatility and low stability, low water solubility, strong influence on organoleptic properties, and phytotoxic effects. Therefore, EO formulations and methods of incorporation to enhance the strengths and compensate for the shortages are outlined. This review also concludes with research directions needed to better understand and fully evaluate EOs and provides an outlook on the prospects for future applications of EOs in organic horticulture production.

Encapsulation of Bioactive Phytochemicals in Plant-Based Matrices and Application as Additives in Meat and Meat Products

The development of plant-based functional food ingredients has become a major focus of the modern food industry as a response to changes in consumer attitudes. In particular, many consumers are switching to a plant-based diet because of their concerns about animal-derived foods on the environment, human health, and animal welfare. There has therefore been great interest in identifying, isolating, and characterizing functional ingredients from botanical sources, especially waste streams from food and agricultural production. However, many of these functional ingredients cannot simply be incorporated into foods because of their poor solubility, stability, or activity characteristics. In this article, we begin by reviewing conventional and emerging methods of extracting plant-based bioactive agents from natural resources including ultrasound-, microwave-, pulsed electric field- and supercritical fluid-based methods. We then provide a brief overview of different methods to characterize these plant-derived ingredients, including conventional, chromatographic, spectroscopic, and mass spectrometry methods. Finally, we discuss the design of plant-based delivery systems to encapsulate, protect, and deliver these functional ingredients, including micelles, liposomes, emulsions, solid lipid nanoparticles, and microgels. The potential benefits of these plant-based delivery systems are highlighted by discussing their use for incorporating functional ingredients into traditional meat products. However, the same technologies could also be employed to introduce functional ingredients into plant-based meat analogs.

Organic Antifungal Drugs and Targets of Their Action

In recent decades, there has been a significant increase in the number of fungal diseases. This is due to a wide spectrum of action, immunosuppressants and other group drugs. In terms of frequency, rapid spread and globality, fungal infections are approaching acute respiratory infections. Antimycotics are medicinal substances endorsed with fungicidal or fungistatic properties. For the treatment of fungal diseases, several groups of compounds are used that differ in their origin (natural or synthetic), molecular targets and mechanism of action, antifungal effect (fungicidal or fungistatic), indications for use (local or systemic infections), and methods of administration (parenteral, oral, outdoor). Several efforts have been made by various medicinal chemists around the world for the development of antifungal drugs with high efficacy with the least toxicity and maximum selectivity in the area of antifungal chemotherapy. The pharmacokinetic properties of the new antimycotics are also important: the ability to penetrate biological barriers, be absorbed and distributed in tissues and organs, get accumulated in tissues affected by micromycetes, undergo drug metabolism in the intestinal microflora and human organs, and in the kinetics of excretion from the body. There are several ways to search for new effective antimycotics: - Obtaining new derivatives of the already used classes of antimycotics with improved activity properties. - Screening of new chemical classes of synthetic antimycotic compounds. - Screening of natural compounds. - Identification of new unique molecular targets in the fungal cell. - Development of new compositions and dosage forms with effective delivery vehicles. The methods of informatics, bioinformatics, genomics and proteomics were extensively investigated for the development of new antimycotics. These techniques were employed in finding and identification of new molecular proteins in a fungal cell; in the determination of the selectivity of drugprotein interactions, evaluation of drug-drug interactions and synergism of drugs; determination of the structure-activity relationship (SAR) studies; determination of the molecular design of the most active, selective and safer drugs for the humans, animals and plants. In medical applications, the methods of information analysis and pharmacogenomics allow taking into account the individual phenotype of the patient, the level of expression of the targets of antifungal drugs when choosing antifungal agents and their dosage. This review article incorporates some of the most significant studies covering the basic structures and approaches for the synthesis of antifungal drugs and the directions for their further development.

Application of essential oils as antimicrobial agents against spoilage and pathogenic microorganisms in meat products

Meat and meat products are perishable products that require the use additives to prevent the spoilage by foodborne microorganisms and pathogenic bacteria. Current trends for products without synthetic preservatives have led to the search for new sources of antimicrobial compounds. Essential oils (EOs), which has been used since ancient times, meet these goals since their effectiveness as antimicrobial agents in meat and meat products have been demonstrated. Cinnamon, clove, coriander, oregano, rosemary, sage, thyme, among others, have shown a greater potential to control and inhibit the growth of microorganisms. Although EOs are natural products, their quality must be evaluated before being used, allowing to grant the Generally Recognized as Safe (GRAS) classification. The bioactive compounds (BAC) present in their composition are linked to their activity, being the concentration and the quality of these compounds very important characteristics. Therefore, a single mechanism of action cannot be attributed to them. Extraction technique plays an important role, which has led to improve conventional techniques in favour of green emerging technologies that allow to preserve better target bioactive components, operating at lower temperatures and avoiding as much as possible the use of solvents, with more sustainable processing and reduced energy use and environmental pollution. Once extracted, these compounds display greater inhibition of gram-positive than gram-negative bacteria. Membrane disruption is the main mechanism of action involved. Their intense characteristics and the possible interaction with meat components make that their application combined with other EOs, encapsulated and being part of active film, increase their bioactivity without modifying the quality of the final product.

Thymol and Thyme Essential Oil-New Insights into Selected Therapeutic Applications

Thymol (2-isopropyl-5-methylphenol) belongs to the phenolic monoterpenes and mostly occurs in thyme species. It is one of the main compounds of thyme essential oil. Both thymol and thyme essential oil have long been used in traditional medicine as expectorant, anti-inflammatory, antiviral, antibacterial, and antiseptic agents, mainly in the treatment of the upper respiratory system. The current search for new directions of biological or therapeutic activities of natural plant substances with known structures includes thyme essential oil and thymol. Novel studies have demonstrated their antibiofilm, antifungal, antileishmanial, antiviral, and anticancer properties. Also, their new therapeutic formulations, such as nanocapsules containing these constituents, can be beneficial in medicinal practice and create opportunities for their extensive use. Extensive application of thymol and thyme essential oil in the healthcare sector is very promising but requires further research and analysis.