α-Terpinene, an Antioxidant in Tea Tree Oil, Autoxidizes Rapidly to Skin Allergens on Air Exposure

Comparison of Approaches for Authentication of Commercial Terpinen-4-ol-type Tea Tree Oils Using Chiral GC/MS

A global demand for tea tree oil (TTO) has resulted in increased adulteration in commercial products. In this study, we use a novel enantiomeric gas chromatography mass spectrometry method for chiral analysis of key terpenes ((±)-terpinen-4-ol, (±)-α-terpineol, and (±)-limonene) and quantification of components present at >0.01% to test different methods of identifying adulterated TTO. Data from authentic Australian (n = 88) and oxidized (n = 12) TTO samples of known provenance were consistent with recommended ranges in ISO 4730:2017 and previously published enantiomeric ratios, with p-cymene identified as the major marker of TTO oxidation. The 15 ISO 4730:2017 constituents comprised between 84.5 and 89.8% of the total ion chromatogram (TIC) peak area. An additional 53 peaks were detected in all samples (7.3-11.0% of TIC peak area), while an additional 43 peaks were detected in between 0 and 99% (0.15-2.0% of the TIC peak area). Analysis of nine commercial samples demonstrated that comparison to the ISO 4730:2017 standard does not always identify adulterated TTO samples. While statistical analysis of minor components in TTO did identify two commercial samples that differed from authentic TTO, the (+)-enantiomer percentages for limonene, terpinen-4-ol, and α-terpineol provided clearer evidence that these samples were adulterated. Thus, straightforward identification of unadulterated and unoxidized TTO could be based on analysis of appropriate enantiomeric ratios and quantitation of the p-cymene percentage.

Fragrances as a trigger of immune responses in different environments

Fragrances can cause allergic skin reactions, expressed as allergic contact dermatitis and reactions in the respiratory tract that range from acute temporary upper airway irritation to obstructive lung disease. These adverse health effects may result from the stimulation of a specific (adaptive) immune response. Th1 cells, which essentially produce interleukin-2 (IL-2) and interferon-γ (IFN-γ), play a key role in allergic contact dermatitis and also on allergic sensitization to common allergens (e.g., nickel and fragrance). It has been shown that fragrance allergy leads to Th2/Th22 production of IL-4, IL-5 and IL-13, controlling the development of IgE and mediating hypersensitivity reactions in the lung, such as asthma. Cytokines released during immune response modulate the expression of cytochrome P450 (CYPs) proteins, which can result in alterations of the pharmacological effects of substances in inflammatory diseases. The mechanisms linking environment and immunity are still not completely understood but it is known that aryl hydrocarbon receptor (AhR) is a sensor with conserved ligand-activated transcription factor, highly expressed in cells that controls complex transcriptional programs which are ligand and cell type specific, with CYPs as targeted genes. This review focuses on these important aspects of immune responses of the skin and respiratory tract cells, describing some in vitro models applied to evaluate the mechanisms involved in fragrance-induced allergy.

Production of Mono-Hydroxylated Derivatives of Terpinen-4-ol by Bacterial CYP102A1 Enzymes

CYP102A1 from Bacillus megaterium is an important enzyme in biotechnology, because engineered CYP102A1 enzymes can react with diverse substrates and produce human cytochrome P450-like metabolites. Therefore, CYP102A1 can be applied to drug metabolite production. Terpinen-4-ol is a cyclic monoterpene and the primary component of essential tea tree oil. Terpinen-4-ol was known for therapeutic effects, including antibacterial, antifungal, antiviral, and anti-inflammatory. Because terpenes are natural compounds, examining novel terpenes and investigating the therapeutic effects of terpenes represent responses to social demands for eco-friendly compounds. In this study, we investigated the catalytic activity of engineered CYP102A1 on terpinen-4-ol. Among CYP102A1 mutants tested here, the R47L/F81I/F87V/E143G/L188Q/N213S/E267V mutant showed the highest activity to terpinen-4-ol. Two major metabolites of terpinen-4-ol were generated by engineered CYP102A1. Characterization of major metabolites was confirmed by liquid chromatography-mass spectrometry (LC-MS), gas chromatography-MS, and nuclear magnetic resonance spectroscopy (NMR). Based on the LC-MS results, the difference in mass-to-charge ratio of an ion (m/z) between terpinen-4-ol and its major metabolites was 16. One major metabolite was defined as 1,4-dihydroxy-p-menth-2-ene by NMR. Given these results, we speculate that another major metabolite is also a mono-hydroxylated product. Taken together, we suggest that CYP102A1 can be applied to make novel terpene derivatives.

Development of Pinaceae and Cupressaceae Essential Oils from Forest Waste in South Korea

The growing awareness of environmental issues has garnered increasing interest in the use of waste material in a wide variety of applications. From this viewpoint, developing essential oils from forest waste can bring new cost opportunities for the effective and sustainable management of unused forestry biomass. However, better knowledge of the production, chemical constituents, and application of essential oils is necessary. Among the species considered to be of interest from the point of view of their essential oils and forest biomass, Pinaceae and Cupressaceae were selected in this study as potential candidates for commercial essential oils based on previous studies. This current study focuses on investigating Pinaceae (Larix kaempferi, Pinus densiflora, and Pinus koraiensis) and Cupressaceae (Chamaecyparis obtusa and Chamaecyparis pisifera) essential oils extracted from various parts from the perspective of their bioactive compounds and potential applications. This is followed by an overview of the essential oils industry in South Korea, with particular attention being paid to utilising unused forest biomass. Therefore, this is a comprehensive review suggesting that Pinaceae and Cupressaceae essential oils extracted from various parts of forest waste could be utilised in various industries, adding value to the aspect of sustainable industry. Furthermore, our study contributes towards capturing the value of forest resources through the utilisation of native essential oils in South Korea.

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.

Cistus albidus L.-Review of a Traditional Mediterranean Medicinal Plant with Pharmacological Potential

Cistus albidus L. (Cistaceae) is a medicinal plant that has been used therapeutically since ancient times in the Mediterranean basin for its important pharmacological properties. The ability of C. albidus to produce large quantities of a wide range of natural metabolites makes it an attractive source of raw material. The main constituents with bioactive functions that exert pharmacological effects are terpenes and polyphenols, with more than 200 identified compounds. The purpose of this review is to offer a detailed account of the botanical, ethnological, phytochemical, and pharmacological characteristics of C. albidus with the aim of encouraging additional pharmaceutical investigations into the potential therapeutic benefits of this medicinal plant. This review was carried out using organized searches of the available literature up to July 2023. A detailed analysis of C. albidus confirms its traditional use as a medicinal plant. The outcome of several studies suggests a deeper involvement of certain polyphenols and terpenes in multiple mechanisms such as inflammation and pain, with a potential application focus on neurodegenerative diseases and disorders. Other diseases such as prostate cancer and leukemia have already been researched with promising results for this plant, for which no intoxication has been reported in humans.

Tea Tree Oil: Properties and the Therapeutic Approach to Acne-A Review

Acne vulgaris is an inflammatory dermatological pathology that affects mostly young people. However, it can also appear in adulthood, mainly in women. It has a high psychosocial impact, not only at the time of active lesions but also due to the consequences of lesions such as scarring and hyperpigmentation. Several factors are involved in the physiopathology of acne and the constant search for active ingredients is a reality, namely phytotherapeutic ingredients. Tea tree oil is an essential oil extracted from Melaleuca alternifolia (Maiden & Betch) Cheel with known antibacterial, anti-inflammatory, and antioxidant properties, making it a candidate for the treatment of acne. This review aims to describe the various properties of tea tree oil that make it a possible ingredient to use in the treatment of acne and to present several human studies that have evaluated the efficacy and safety of using tea tree oil in the treatment of acne. It can be concluded that tea tree oil has good antibacterial, anti-inflammatory, and antioxidant properties that result in a decrease in the number of inflammatory lesions, mainly papules, and pustules. However, given the diversity of study designs, it is not possible to draw concrete conclusions on the efficacy and safety of this oil in the treatment of acne.

Bioactive Chemical Constituents of Matthiola longipetala Extract Showed Antioxidant, Antibacterial, and Cytotoxic Potency

The exploration of bioactive compounds from natural resources attracts the attention of researchers and scientists worldwide. M. longipetala is an annual aromatic herb that emits a pleasant odor during the night. Regarding the chemical composition and biological characteristics, M. longipetala extracts are poorly studied. The current study aimed to characterize the chemical composition of M. longipetala methanol extract using GC-MS and determine its biological potencies, including its capacity for cytotoxicity and antioxidant and antibacterial activities. In this approach, 37 components were identified, representing 99.98% of the total mass. The major chemical components can be classified as oxygenated hydrocarbons (19.15%), carbohydrates (10.21%), amines (4.85%), terpenoids (12.71%), fatty acids and lipids (50.8%), and steroids (2.26%). The major identified compounds were ascaridole epoxide (monoterpene, 12.71%) and methyl (E)-octadec-11-enoate (ester of fatty acid, 12.21%). The extract of M. longipetala showed substantial antioxidant activity. Based on the DPPH and ABTS scavenging, the antioxidant activity of the extracted components of M. longipetala revealed that leaf extract is the most effective with IC50 values of 31.47 and 28.94 mg/L, respectively. On the other hand, the extracted plant showed low antibacterial activities against diverse bacterial species, viz., Escherichia coli, Klebsiella pneumonia, Staphylococcus epidermidis, S. haemolyticus, and S. aureus. The most potent antibacterial results were documented for leaf and flower extracts against E. coli and S. aureus. Additionally, the extract’s effectiveness against HepG2 cells was evaluated in vitro using the measures of MTT, DNA fragmentation, and cell proliferation cycle, where it showed considerable activity. Therefore, we can conclude that M. longipetala extract displayed improvement in cytocompatibility and cell migration properties. In conclusion, M. longipetala could be considered a potential candidate for various bioactive compounds with promising biological activities. However, further characterization of the identified compounds, particularly the major compounds, is recommended to evaluate their efficacy, modes of action, and safety.

Sesquiterpenes and monoterpenes from different varieties of guava leaf essential oils and their antioxidant potential

Despite that Sri Lanka is a biodiversity hotspot with numerous guava varieties (Psidium guajava L.), no adequate scientific research has been reported on leaf essential oil (EO) composition based on varieties and its pharmacological properties, namely antioxidant properties. Therefore, this study focused to evaluate the chemical compositions and antioxidative capacity of EOs isolated from leaves of seven guava varieties grown in Sri Lanka, including apple-guava (P. pomiferum , PGA), common-guava (P. guaja v a , PGCG), two wild-guava; cultivar of P. guajava (PGG) and a cultivar of P. guineense (PGE), two introduced varieties of P. guajava (PGK and PGP), and one introduced variety of P. guineense (PGC). The EOs were isolated using hydro-distillation and the chemical compositions were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) technique, and the compounds that showed greater than 90% matching value were considered for characterization. The yields of EOs ranged from 0.02-0.26% (w/w) where PGE produced the greatest amount. About sixty-eight chemical compounds were identified from seven varieties and Sesquiterpenes were found to be the most abundant in the PGCG, PGG, PGE, and PGA varieties, whereas monoterpenes were found to be the most abundant in PGK, PGP, and PGC varieties. The sesquiterpenes, Nerolidol (70.0-7.9%), (-)-Globulol (21.0-7.0%), and Caryophyllene (20.4-1.4%) and monoterpenes, D-Limonene (30.3-14.1 %) were found as the major compounds of all studied guava varieties. Twenty-eight compounds were identified for the first time in guava EOs, including Cadinadiene-1,4, Benzylacetaldehyde, and Epiglobulol. The antioxidant efficacy of EOs varied from 329.56 ± 2.01 to 85.70 ± 2.01 μL Trolox Eq/L, where PGE showed the highest antioxidative potential. Ultimately, the chemical constituents and antioxidant capacity of isolated EOs varied with the variety, with EO from PGE leaves exerting an amazing antioxidant capacity compared to the others and being rich in Nerolidol. The findings of this study fill the gap in the literature on chemical constituents in the EO of guava leaves, and also it will open the avenue to discover novel potential compounds with outstanding pharmacological activities from guava leaves.

Optimization and characterization of a novel tea tree oil-integrated poly (ε-caprolactone)/soy protein isolate electrospun mat as a wound care system

A set of poly (ε-caprolactone)/soy protein isolate (PCL/SPI) mats with different ratios of PCL to SPI was fabricated using the electrospinning method. The mat with PCL to SPI ratio of 95:5 (PS 95:5) had the narrowest nanofibers, the highest percentage of porosity, the lowest swelling ratio, the least vapor transmission, and the slowest degradation rate among the prepared mats. The hemolysis assay indicated that all mats can be considered biocompatible biomaterials. In continue, three different weight ratios of tea tree oil (TTO) were loaded into the PS 95:5 mat. The release profiles illustrated that higher amounts of TTO could be released in an acidic environment. The antioxidant activity of the mats increased by the increase in their TTO content. The cell viability test, cell adhesion images, and live/dead assay of TTO-loaded mats affirmed that all fabricated mats were biocompatible. The scratch wound assay expressed that TTO accelerates the rate of wound closure. The TTO-loaded mats illustrated antibacterial activity against both Escherichia coli and Staphylococcus aureus bacteria. The obtained outcomes revealed that TTO-loaded PCL/SPI mats can be considered promising potential wound dressings.

Application of direct peptide reactivity assay for assessing the skin sensitization potential of essential oils

Plant-derived products are frequently found as ingredients in cosmetics. However, the current data show non-neglectable skin sensitizing potential of these preparations suggesting an urgent need for data regarding their health safety profile. The aim of this study was to assess the skin sensitization potential of commercial essential oils by selected Lamiaceae species (Lavandula angustifolia, Melissa officinalis, Mentha longifolia, Thymus vulgaris, Salvia officinalis, and Rosmarinus officinalis) using a chemistry-based Direct Peptide Reactivity Assay (DPRA) in order to predict their potential allergic properties. In the DPRA assay, nucleophile-containing synthetic peptides (cysteine peptide and lysine peptide) were incubated with the test substance for 24 h. Depletion of the peptide in the reaction mixture was measured by high-pressure liquid chromatography (HPLC) using UV detection and the average peptide depletion data for cysteine and lysine was then calculated. Menthae longifoliae aetheroleum showed no or minimal reactivity with 4.48% cysteine depletion, Rosmarini aetheroleum and Salviae aetheroleum showed low reactivity with the 12.79% and 15.34% of cysteine depletion, respectively, while the other analyzed essential oils showed moderate reactivity with the cysteine depletion between 23.21 and 48.43%. According to DPRA predictive analysis, only Menthae longifoliae aetheroleum can be classified as negative, while all other essential oils may be classified as positive, thus having the potential to cause skin sensitization.

RIFM fragrance ingredient safety assessment, (-)-(R)-α-phellandrene, CAS Registry Number 4221-98-1

Therefore, the (-)-(R)-α-phellandrene MOE for the repeated dose toxicity endpoint can be calculated by dividing the (-)-(R)-α-phellandrene NOAEL in mg/kg/day by the total systemic exposure to (-)-(R)-α-phellandrene, 8.33/0.00040, or 20825.

Effects of Three-Layer Encapsulated Tea Tree Oil on Growth Performance, Antioxidant Capacity, and Intestinal Microbiota of Weaned Pigs

Tea tree oil (TTO) exerts key roles in improving growth performance of pigs. However, knowledge is limited regarding comparative effects of Encp TTO and Un-encp TTO supplementation on growth performance of pigs. A study determined the effects of TTO or its capsulation on growth performance, antioxidant capacity, and intestinal microbiome of weaned pigs. A total of 144 healthy pigs (8.5 ± 0.24 kg) were subjected to four treatments for a 28-d trial with six replicates per treatment and six pigs per pen: negative control, NC; positive control, PC (antibiotic supplemented); Un-encp TTO (supplemented with unencapsulated TTO); Encp TTO (supplemented with encapsulated TTO). NC, TTO, and PC treatments were compared with regard to improved average daily gain (ADG), average daily feed intake (ADFI), feed conversion rate, nutrient digestibility, and intestinal morphology (p < 0.05) and decreased diarrhea rate. TTO- and PC-treated pigs had higher levels of serum superoxide dismutase, glutathione peroxidase, and immunoglobulin G; lower levels of liver aspartate aminotransferase and alanine aminotransferase; and improved concentrations of interleukin 10 (IL-10), tumor necrosis factor α, and IL-1β (p < 0.05). TTO- and PC-treated pigs had higher abundance of beneficial bacterial species Subdoligranulum and lower abundance of diarrhea associated species Escherichia-Shigella in cecal and colonic digesta (p < 0.05). Encapsulation of TTO preserved more activities of TTO than its unencapsulated counterpart by showing higher ADG, ADFI, and feed conversion rate during day 1 (d1) to d14 (p < 0.05) and tended to lower diarrhea rate (p = 0.083) and improve villous height/crypt depth (VH/CD) ratio (p = 0.089) in jejunum. Encapsulation of TTO also improved antioxidant indexes and decreased liver injury and inflammation accordingly (p < 0.05). Encapsulated TTO-treated pigs had higher abundance of beneficial Clostridium_sensu_stricto_1 and lower the abundance of harmful Escherichia-Shigella in cecal and colonic digesta (p < 0.05). Our results demonstrated TTO benefits on improving growth performance of weaned pigs and further proved that encapsulation of TTO was superior to its unencapsulated counterpart at multiples. Encapsulated TTO was similar to the PC group and could be potentially an alternative of feed antibiotics for weaned pigs.

Quantification of volatile organic compounds by secondary electrospray ionization-high resolution mass spectrometry

Secondary electrospray ionization coupled with high resolution mass spectrometry (SESI-HRMS) is a direct mass spectrometry technique, which can identify trace volatile organic compounds (VOCs) in real time without sample pretreatment and chromatographic separation. SESI-HRMS has been successfully applied in multiple applications, including breath analysis, animals and plants VOCs emissions, analysis of headspace of cell cultures and indoor and outdoor air. The range of areas where the technique can potentially have a substantial impact is very broad. However, one critical aspect that requires further development to consolidate the technique is absolute quantification. Therefore, in this study we aim to develop a quantitative method for eight representative VOCs, including ketones (acetone, 2-butanone and 2-pentanone), alkenes (isoprene and α-terpinene) and aromatics (toluene, styrene and mesitylene). The mass spectrometric platform includes a commercial SESI source hyphenated with a Q-Exactive hybrid quadrupole Orbitrap high resolution mass spectrometer. Within the concentration range of 0-100 ppbv studied, the optimal coefficient of determination for linear regression (R² = 0.993-0.999) between signal intensity and concentration is obtained in the range of 0-10 ppbv for all eight VOCs. The detection limits range between 3 (2-Pentanone) and 15 (Acetone) pptv. The intra-day (n = 10) and inter-day (n = 30) coefficients of variation (CV) are ≤ 6% and ≤10%, respectively. Finally the method is applied for the fast evaluation (<5 min) of different materials widely used for the collection, storage or pretreatment of gas sample. Better recovery of trace levels of eight VOCs is observed for PTFE gas sampling bag as compared to Nalophan and Tedlar bags; when Nafion tube is used to pretreat the gas sample, recovery of ≤50% are obtained for 2-pentanone, α-terpinene and all three aromatics.

Thymus satureioides and Origanum majorana essential oils improve the quality of Beni Arouss buck semen during storage at 4°C

This study aims to investigate the effects of essential oils (EOs), extracted from Thymus satureioides (TS) and Origanum majorana (OM), on Beni Arouss buck semen quality stored in skimmed milk at 4°C. EOs were extracted by hydro-distillation, and the chemical compounds were determined. Ejaculates were collected from six Beni Arouss bucks, once a week for 10 weeks, and they were pooled, divided into five equal aliquots and diluted to 400 × 10⁶ sperm/ml with skimmed milk supplemented with 0.01% of OM EO, 0.01% of TS EO, 0.05% of OM EO and 0.05% of TS EO. Non-supplemented skimmed milk was considered as a control. Semen motility, kinematic parameters, viability, abnormality, membrane integrity and lipid peroxidation were evaluated at 0, 4, 8, 24, 28, 32 and 48 hr of liquid storage at 4°C. The main EO components were carvacrol (31.7%), thymol (28.0%) and borneol (14.4%) for TS, and terpinene-4-ol (31.2%), γ-terpinene (17.4%) and α-terpinene (12.7%) for OM. The results highlighted a dose-dependent effect of TS and OM EOs on all semen quality parameters. 0.01% of both EOs had a beneficial effect on the sperm preservation stored at 4°C compared with control (p < .05) excepted for the straight-line velocity. The 0.05% EO addition had harmful effects during storage particularly for TS EO. In conclusion, 0.01% of TS and OM EOs are recommended to improve the Beni Arouss buck semen preservation at 4°C.

Ethnomedical uses, chemical constituents, and evidence-based pharmacological properties of Chenopodium ambrosioides L.: extensive overview

Background

The Chenopodium genus is a plant family widely spread worldwide that includes various plant species reputed to possess several medicinal virtues in folk medicines. Chenopodium ambrosioides L. is among the most used plants in traditional medicines worldwide. This review aimed to highlight ethnomedicinal uses, phytochemical status, and pharmacological properties of C. ambrosioides L.

Main body of the abstract

The analysis of relevant data highlights various ethnomedicinal uses against human and veterinary diseases in forty countries. Most indications consisted of gastrointestinal tract dysfunctioning troubles and worms parasitemia. Around 330 chemical compounds have been identified in different plant parts, especially in its essential oil fractions (59.84%). However, only a few compounds—mainly monoterpenes and glycosides—have been isolated and characterized. Experimental pharmacological studies validated a large scale of significant health benefits. It appeared that many monoterpenes are antioxidant, insecticidal, trypanocidal, analgesic, antifungal, anti-inflammatory, anti-arthritic, acaricidal, amoebicidal, anthelmintic, anticancer, antibacterial, antidiabetic, antidiarrheal, antifertility, antifungal, anti-leishmanial, antimalarial, antipyretic, antisickling, antischistosomal, antiulcer, anxiolytic, immunomodulatory, molluscicidal, and vasorelaxant agents.

Short conclusion

Thus, the Chenopodium ambrosioides species necessitates further chemical studies to isolate and characterize new bioactive secondary metabolites and pharmacological investigations to precise the mechanisms of action before clinical trials.

Myorelaxant Effect of the Dysphania ambrosioides Essential Oil on Sus scrofa domesticus Coronary Artery and Its Toxicity in the Drosophila melanogaster Model

PURPOSE

Alternative methods for the use of animals in research have gained increasing importance, due to assessments evaluating the real need for their use and the development of legislation that regulates the subject. The principle of the 3R's (replacement, reduction and refinement) has been an important reference, such that in vitro, ex vivo and cord replacement methods have achieved a prominent place in research.

METHODS

Therefore, due to successful results from studies developed with these methods, the present study aimed to evaluate the myorelaxant effect of the Dysphania ambrosioides essential oil (EODa) using a Sus scrofa domesticus coronary artery model, and the toxicity of both the Dysphania ambrosioides essential oil and its major constituent, α-terpinene, against Drosophila melanogaster in toxicity and negative geotaxis assays.

RESULTS

The EODa relaxed the smooth muscle of swine coronary arteries precontracted with K⁺ and 5-HT in assays using Sus scrofa domesticus coronary arteries. The toxicity results presented LC₅₀ values of 1.546 mg/mL and 2.282 mg/mL for the EODa and α-terpinene, respectively, thus showing the EODa and α-terpinene presented toxicity to these dipterans, with the EODa being more toxic.

CONCLUSIONS

Moreover, the results reveal the possibility of using the EODa in vascular disease studies since it promoted the relaxation of the Sus scrofa domesticus coronary smooth muscle.

Synthesis, Characterization, and Catalytic Applications of the Ti-SBA-16 Porous Material in the Selective and Green Isomerizations of Limonene and S-Carvone

This work presents studies on the activity of the Ti-SBA-16 (SBA—Santa Barbara Amorphous) catalyst in the isomerization of limonene and S-carvone. The Ti-SBA-16 catalyst was synthesized by a two-step method: first, the SBA-16 material was produced, and then it was impregnated with the titanium source. The Ti-SBA-16 catalyst was subjected to detailed characterizations by means of instrumental methods: XRD (X-ray Diffraction), UV-Vis (Ultraviolet–Visible) spectroscopy, FTIR (Fourier-Transform Infrared) spectroscopy, SEM (Scanning Electron Microscopy) with EDX (Energy Dispersive X-ray) spectroscopy, and EDXRF (Energy Dispersive X-ray Fluorescence). Both limonene and S-carvone underwent isomerization over the Ti-SBA-16 catalyst. In the isomerization of limonene, the main product was terpinolene, and its highest yield amounted to 39 mol% after 300 min at 170 °C with a catalyst content of 15 wt%. Under these conditions, the conversion of limonene reached 78 mol%. In contrast, the highest yield of carvacrol (65 mol%) was obtained with the catalyst content of 15 wt%, at 200 °C, and with the conversion of S-carvone reaching 79 mol%.

The Influence of Trichoderma harzianum Rifai T-22 and Other Biostimulants on Rhizosphere Beneficial Microorganisms of Carrot

The principles of good agricultural and horticultural practice, which consider both giving environmental protection and high yielding of plants, require modern cultivation methods. Modern cultivation of horticultural plants uses, for example, cover crops, living mulches, plant growth-promoting microorganisms (PGPMs), plant growth regulators (PGRs) and other biostimulants protecting the soil against degradation and plants against phytopathogens and stress. The purpose of field and laboratory studies was to determine the effect of Trianum P (containing Trichoderma harzianum Rifai T-22 spores), Beta-Chikol (a.s.—chitosan), Timorex Gold 24 EC (based on tea tree oil) and fungicide Zaprawa Nasienna T 75 DS/WS (a.s.—tiuram 75%) on the health of carrot (Daucus carota L.) plants and the microorganism population in the rhizosphere of this plant. Moreover, the antagonistic effect of rhizosphere fungi on selected carrot fungal pathogens was determined. Laboratory mycological analysis allowed one to determine the qualitative and quantitative composition of fungi colonizing the underground parts of carrot plants. In addition, the total population of fungi and bacteria was determined (including Bacillus sp. and Pseudomonas sp.) based on the microbiological analysis of the rhizosphere soil. The application of the plant growth-promoting fungus (Trichoderma harzianum T-22), chitosan and tea tree oil positively influenced the growth, development and health status of carrot plants. T. harzianum T-22, chitosan and fungicide most effectively protected carrots against infection by soil-borne fungi from the genus Alternaria, Fusarium, Haematonectria, Sclerotinia and Rhizoctonia. The rhizosphere population of Bacillus sp. and Pseudomonas sp. in the treatments with Trianum P or Zaprawa Nasienna T 75 DS/WS was bigger than in the other experimental treatments. A reverse relationship was observed in the population of rhizosphere fungi. T. harzianum T-22, chitosan and tea tree oil promoted the growth of antagonistic fungi (Albifimbria sp., Clonostachys sp., Penicillium sp., Talaromyces sp. and Trichoderma sp.) in the carrot rhizosphere. Antagonistic activity of these fungi towards Alternaria dauci, Alternaria radicina, Sclerotiniasclerotiorum and Rhizoctonia solani was higher after the application of the preparations compared to control. Consequently, Trianum P, Beta-Chikol and Timorex Gold 24 EC can be recommended as plant biostimulants in ecological agricultural production, including Daucus carota cultivation.

Topical ivermectin-metronidazole gel therapy in the treatment of blepharitis caused by Demodex spp.: A randomized clinical trial

PURPOSE

To evaluate the efficacy of topical ivermectin-metronidazole combined therapy in the management of Demodex-associatedblepharitis.

METHODS

Sixty patients with a diagnosis of Demodex-associatedblepharitis were recruited in a randomized clinical trial. Thirty receiving topical ivermectin (0.1%)-metronidazole (1%) gel treatment on days 0, 15 and 30. Thirty additional patients were used as a control group receiving vehicle on days 0, 15 and 30. The primary efficacy measure was the number of Demodex spp. mitesin the eyelashes of patients. The secondary outcomes included clinical improvement of signs and adverse events.

RESULTS

Complete eradication of Demodex spp. was found in 96.6% of patients in the treatment group. Furthermore, a significant reduction of inflammation signs were found in all treated patients versus controls. None of the patients experienced any adverse effects associated with the treatment.

CONCLUSION

Demodex infection was controlled satisfactorily with the ivermectin (0.1%)-metronidazole (1%) gel, and no adverse effects were observed. Application of this gel for the treatment of different parasitic infections of the eyelids could be feasible, and this requires further exploration.

Therapeutic Potential of Volatile Terpenes and Terpenoids from Forests for Inflammatory Diseases

Forest trees are a major source of biogenic volatile organic compounds (BVOCs). Terpenes and terpenoids are known as the main BVOCs of forest aerosols. These compounds have been shown to display a broad range of biological activities in various human disease models, thus implying that forest aerosols containing these compounds may be related to beneficial effects of forest bathing. In this review, we surveyed studies analyzing BVOCs and selected the most abundant 23 terpenes and terpenoids emitted in forested areas of the Northern Hemisphere, which were reported to display anti-inflammatory activities. We categorized anti-inflammatory processes related to the functions of these compounds into six groups and summarized their molecular mechanisms of action. Finally, among the major 23 compounds, we examined the therapeutic potentials of 12 compounds known to be effective against respiratory inflammation, atopic dermatitis, arthritis, and neuroinflammation among various inflammatory diseases. In conclusion, the updated studies support the beneficial effects of forest aerosols and propose their potential use as chemopreventive and therapeutic agents for treating various inflammatory diseases.

Star anise (Illicium verum): Chemical compounds, antiviral properties, and clinical relevance

Medicinal herbs are one of the imperative sources of drugs all over the world. Star anise (Illicium verum), an evergreen, medium-sized tree with star-shaped fruit, is an important herb with wide distribution throughout southwestern parts of the Asian continent. Besides its use as spice in culinary, star anise is one of the vital ingredients of the Chinese medicinal herbs and is widely known for its antiviral effects. It is also the source of the precursor molecule, shikimic acid, which is used in the manufacture of oseltamivir (Tamiflu®), an antiviral medication for influenza A and influenza B. Besides, several other molecules with numerous biological benefits including the antiviral effects have been reported from the same plant. Except the antiviral potential, star anise possesses a number of other potentials such as antioxidant, antimicrobial, antifungal, anthelmintic, insecticidal, secretolytic, antinociceptive, anti-inflammatory, gastroprotective, sedative properties, expectorant and spasmolytic, and estrogenic effects. This review aimed to integrate the information on the customary attributes of the plant star anise with a specific prominence on its antiviral properties and the phytochemical constituents along with its clinical aptness.

An Endophytic Diaporthe apiculatum Produces Monoterpenes with Inhibitory Activity against Phytopathogenic Fungi

Volatile organic compounds (VOCs) from endophytic fungi are becoming a potential antibiotic resource. The inhibitive effects of VOCs produced by an endophytic fungus in Leucaena leucocephala were investigated on plant pathogens in this study. Using standard morphological methods and multigene phylogeny, the fungus was identified as Diaporthe apiculatum strain FPYF 3052. Utilizing a two- compartment Petri plate bioassay method, the VOCs from this fungus showed bioactivity ranging from 23.8% to 66.7% inhibition on eight plant pathogens within 24 hours. The SPME-GC/MS technique identified fifteen volatile compounds with dominant terpenoids γ-terpinene (39.8%), α-terpinene (17.2%), and (-)-4-terpineol (8.4%) from the VOCs. Commercial α-terpinene, γ-terpinene, and (-)-4-terpineol demonstrated inhibition on the tested pathogens at concentrations from 0.2 to 1.0 µl/ml within 72 h in the bioassay system. The inhibition rates were from 28% to 100% percent using 1.0 µl/ml within 48 h. (-)-4-Terpineol was the most active of the terpenoids causing up to 100% inhibition. The data illustrate that these monoterpenes play an important role in the inhibitive bioactivity of the VOCs of D. apiculatum FPYF 3052. Most importantly, (-)-4-terpineol is now for the first time, reported to have capability of strong antifungal activity and could be developed as an antibiotic substance.

Natural Monoterpenes: Much More than Only a Scent

Terpenes are a widespread group of secondary metabolites that can be found in various family plants such as the Lamiaceae. In view of their numerous valuable biological activities, the industrial production of concrete terpenes and essential oils rich in the substances is intensively studied. Monoterpenes constitute a significant part of the whole group of the aforementioned secondary metabolites. This is due to their numerous biological activities and their ability to permeate the skin. Despite the fact that these substances have gain popularity, they are not comprehensively characterized. The presented review is based on studies of the biological activities of the most important monoterpenes and the essential oils rich in these compounds. The authors focused attention on antioxidant activity, inhibition towards acetyl- and butyrylcholinesterase, and α-amylase and α-glucosidase, antifungal, hepatoprotective, sedative properties, and their skin permeation enhancement.

Medicinal Properties of Cannabinoids, Terpenes, and Flavonoids in Cannabis, and Benefits in Migraine, Headache, and Pain: An Update on Current Evidence and Cannabis Science

BACKGROUND

Comprehensive literature reviews of historical perspectives and evidence supporting cannabis/cannabinoids in the treatment of pain, including migraine and headache, with associated neurobiological mechanisms of pain modulation have been well described. Most of the existing literature reports on the cannabinoids Δ⁹ -tetrahydrocannabinol (THC) and cannabidiol (CBD), or cannabis in general. There are many cannabis strains that vary widely in the composition of cannabinoids, terpenes, flavonoids, and other compounds. These components work synergistically to produce wide variations in benefits, side effects, and strain characteristics. Knowledge of the individual medicinal properties of the cannabinoids, terpenes, and flavonoids is necessary to cross-breed strains to obtain optimal standardized synergistic compositions. This will enable targeting individual symptoms and/or diseases, including migraine, headache, and pain.

OBJECTIVE

Review the medical literature for the use of cannabis/cannabinoids in the treatment of migraine, headache, facial pain, and other chronic pain syndromes, and for supporting evidence of a potential role in combatting the opioid epidemic. Review the medical literature involving major and minor cannabinoids, primary and secondary terpenes, and flavonoids that underlie the synergistic entourage effects of cannabis. Summarize the individual medicinal benefits of these substances, including analgesic and anti-inflammatory properties.

CONCLUSION

There is accumulating evidence for various therapeutic benefits of cannabis/cannabinoids, especially in the treatment of pain, which may also apply to the treatment of migraine and headache. There is also supporting evidence that cannabis may assist in opioid detoxification and weaning, thus making it a potential weapon in battling the opioid epidemic. Cannabis science is a rapidly evolving medical sector and industry with increasingly regulated production standards. Further research is anticipated to optimize breeding of strain-specific synergistic ratios of cannabinoids, terpenes, and other phytochemicals for predictable user effects, characteristics, and improved symptom and disease-targeted therapies.

TLC-bioautography identification and GC-MS analysis of antimicrobial and antioxidant active compounds in Musa × paradisiaca L. fruit pulp essential oil

INTRODUCTION

The absence of microbial growth and resistance to oxidative deterioration in fruits of Musa × paradisiaca L. (bananas) is an indication of the presence of antimicrobial and antioxidant metabolites.

OBJECTIVE

In order to investigate the secondary metabolomic spectrum as well as the active antimicrobial and antioxidants present in essential oils (EOs) from fruits of different geographical areas of M. × paradisiaca, gas chromatography-mass spectroscopy (GC-MS) principal component data correlation analysis is complemented with antimicrobial assays and phytochemical and bioautographic antioxidant fingerprints with thin layer chromatography (TLC).

METHODOLOGY

An EO was obtained by steam distillation and subjected to GC-MS and TLC for metabolomic profiling from fruit pulp. The antimicrobial potential was tested in both Escherichia coli as a gram negative and Bacillus subtilis as a gram positive microbe. Potential antioxidant metabolites were identified through TLC-bioautography and GC-MS analysis of active zones.

RESULTS

A maximum of 0.56% v/w EO was isolated from fruit pulps of M. × paradisiaca. Minimum inhibitory concentrations (MICs) against B. subtillis and E. coli were 0.25 and 0.35 μg/mL, respectively. Thus, 56 metabolites were identified through GC-MS. The major abundant antimicrobial metabolites found in EOs are α-thujene, γ-terpinene, α- and β-pinene, sabinene, β-myrcene, limonene, α-capaene, caryophyllene and (Z,E)-α farnesene. Aceteugenol, palmitic acid, stearic acid, palmitin, and stearin were identified as antioxidant metabolites. Principal component analysis of metabolite data reveals correlations and a clear separation based on metabolites obtained from various areas.

CONCLUSION

The data generated using metabolic profiling and cluster analysis helped to identify antimicrobial and antioxidant compounds in M. × paradisiaca.

Medicinal properties of terpenes found in Cannabis sativa and Humulus lupulus

Cannabaceae plants Cannabis sativa L. and Humulus lupulus L. are rich in terpenes - both are typically comprised of terpenes as up to 3-5% of the dry-mass of the female inflorescence. Terpenes of cannabis and hops are typically simple mono- and sesquiterpenes derived from two and three isoprene units, respectively. Some terpenes are relatively well known for their potential in biomedicine and have been used in traditional medicine for centuries, while others are yet to be studied in detail. The current, comprehensive review presents terpenes found in cannabis and hops. Terpenes' medicinal properties are supported by numerous in vitro, animal and clinical trials and show anti-inflammatory, antioxidant, analgesic, anticonvulsive, antidepressant, anxiolytic, anticancer, antitumor, neuroprotective, anti-mutagenic, anti-allergic, antibiotic and anti-diabetic attributes, among others. Because of the very low toxicity, these terpenes are already widely used as food additives and in cosmetic products. Thus, they have been proven safe and well-tolerated.

Aromatherapy: composition of the gaseous phase at equilibrium with liquid bergamot essential oil

This work compares the composition at different temperatures of gaseous phase of bergamot essential oil at equilibrium with the liquid phase. A new GC-MS methodology to determine quantitatively the volatile aroma compounds was developed. The adopted methodology involved the direct injection of headspace gas into injection port of GC-MS system and of known amounts of the corresponding authentic volatile compounds. The methodology was validated. This study showed that gaseous phase composition is different from that of the liquid phase at equilibrium with it.

The Isomerization of Limonene over the Ti-SBA-15 Catalyst—The Influence of Reaction Time, Temperature, and Catalyst Content

The isomerization of limonene over the Ti-SBA-15 catalyst, which was prepared by the hydrothermal method, was studied. The main products of limonene isomerization were terpinolene, α-terpinene, γ-terpinene, and p-cymene—products with numerous applications. The amount of these products depended on reaction time, temperature, and catalyst content. These parameters changed in the following range: reaction time 30–1380 min, temperature 140–160 °C, and catalyst content 5–15 wt %. Finally, the most favorable conditions for the limonene isomerization process were established: a reaction time of 180 min, temperature of 160 °C, and amount of the catalyst 15 wt %. In order to obtain p-cymene (dehydroaromatization product), the most favorable conditions are similar but the reaction time should be 1380 min. The application of such conditions allowed us to obtain the highest amounts of the desired products in the shortest time.

Biotransformation and bioactivation reactions - 2016 literature highlights

We are pleased to present a second annual issue highlighting a previous year's literature on biotransformation and bioactivation. Each contributor to this issue worked independently to review the articles published in 2016 and proposed three to four articles, which he or she believed would be of interest to the broader research community. In each synopsis, the contributing author summarized the procedures, analyses and conclusions as described in the original manuscripts. In the commentary sections, our authors offer feedback and highlight aspects of the work that may not be apparent from an initial reading of the article. To be fair, one should still read the original article to gain a more complete understanding of the work conducted. Most of the articles included in this review were published in Drug Metabolism and Disposition or Chemical Research in Toxicology, but attempts were made to seek articles in 25 other journals. Importantly, these articles are not intended to represent a consensus of the best papers of the year, as we did not want to make any arbitrary standards for this purpose, but rather they were chosen by each author for their notable findings and descriptions of novel metabolic pathways or biotransformations. I am pleased that Drs. Rietjens and Dalvie have again contributed to this annual review. We would like to welcome Grover P Miller as an author for this year's issue, and we thank Tom Baillie for his contributions to last year's edition. We have intentionally maintained a balance of authors such that two come from an academic setting and two come from industry. Finally, please drop us a note if you find this review helpful. We would be pleased to hear your opinions of our commentary, and we extend an invitation to anyone who would like to contribute to a future edition of this review. This article is dedicated to Professor Thomas Baillie for his exceptional contributions to the field of drug metabolism.