Chemical and Olfactory Analysis of the Volatile Fraction of Ocimum gratissimum Concrete from Madagascar.

The chemical composition of the volatile fraction of Ocimum gratissimum concrete (romba) from Madagascar has been determined for the first time by GC/MS and GC-FID. A methyl cinnamate chemotype has been determined for this material, along with a set of compounds typical in essential oils and extracts from plants of the Ocimum genus. Variability was mostly observed on terpenes and terpenoids components. GC-O-MS was also used for a sensory evaluation of this material performed by a master perfumer. The chemical composition of this O. gratissimum extract was then compared with literature data to assess subtle differences between chemotypes of the same species and other species of the same genus within natural variability. A mapping illustrates the occurrence of the cinnamate chemotype in Eastern Africa, India and now Madagascar, while other origins generally present eugenol, thymol, camphor, or linalool chemotypes.

The Effects of Clove and Its Constituents on Reproductive System: a Comprehensive Review.

Clove with the scientific name of Syzygium aromaticum (L.) Merr. & L.M. Perry is an evergreen tree in which its buds are used for medicinal purposes. Traditional medicine manuscripts as well as recent studies reported its effects on male and female reproductive systems. The aim of this study is to investigate the reported contradictory effects of clove and its phytochemicals on the reproductive system of both males and females. All types of in vitro, animal, and human studies of clove and its main constituents in the field of reproductive systems were collected via searching electronic databases including PubMed and Scopus from the onset till 2021. In this review, 76 articles were included, of which 25 were related to male reproduction, 32 were related to female reproduction, and 19 were related to reproductive malignancies. Analysis of the literature indicates the effects of clove and its constituents especially eugenol and ß-caryophyllene on the level of sex hormones, fertility, sperm abnormalities, endometriosis, menstrual cycle, as well as gynecological infections, and reproductive tumors. The main mechanism of clove has not been understood yet but it seems that different parameters affect its pharmacological activity including the type of extract, dose, and duration of administration as well as the primary cause of the disorder. According to the effects of clove on different parts of the reproductive system, it seems that it can be a suitable candidate for related disorders, provided that more and more detailed studies are done on it.

Antibacterial activity of essential oils extracted from the unique Chinese spices cassia bark, bay fruits and cloves.

Spices are widely used in daily life such as diet and have certain activity. Especially in China, spices have been mainly used as condiments for thousands of years in order to improve the sensory quality of food; in addition, they and their derivatives can also be used as preservatives. In this study, three spices with unique Chinese characteristics widely used were selected: cassia bark (bark of Cinnamomum camphora Presl), bay fruits (Laurus nobilis), and cloves (Syzygiumaromaticum). The main components and antibacterial ability of these three spices were analyzed by simulated extraction method. Through headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) analysis, it was determined that the main active compounds in the essential oils of cassia bark, bay fruits and cloves were cinnamaldehyde (78.11%), cinnamaldehyde (61.78%) and eugenol (75.23%), respectively. The agar plate diffusion test and the simulated food culture medium experiment confirmed that the essential oils extracted from the three flavors have antibacterial effects on Listeria monocytogenes, Listeria innocua, Listeria welshimeri, Listeria ivanovii, Listeria grayi and Vibrio parahaemolyticus. The antibacterial activity of different strains has different optimal extraction conditions. Generally speaking, cinnamon essential oil has the strongest antibacterial activity, while laurel fruit has the lowest antibacterial activity. The study proved the antibacterial activity of these three Chinese-specific spices and provided some new ideas and methods for the subsequent research and preparation of natural food additives and food antibacterial agents.

Essential Oil Composition and Stable Isotope Profile of Cultivated Ocimum campechianum Mill. (Lamiaceae) from Peru.

Ocimum campechianum Mill. (Peruvian basil) is an essential oil-bearing plant of the Lamiaceae family. Volatile oil produced through steam distillation of Peruvian basil was examined to establish the aromatic and stable isotope profiles of samples (n = 9) from three different cultivated plots in Peru. The resulting essential oils were analyzed by GC/FID, GC/MS, and GC/IRMS. In accordance with findings from other researchers, multiple chemotypes, defined by the most abundant aromatic compounds, exist within these populations. Overall, 55% of samples are the eugenol chemotype (values ranging 15.4-30.2%), 33% are the methyl eugenol chemotype (values ranging 68.1-68.7%), and a single sample is a mixture of both chemotypes, containing high levels of both eugenol (38.1%) and methyl eugenol (8.6%). Stable isotope ratios, δ2H and δ13C, performed on prominent compounds provide supporting data for distinguishing chemotypes. Complete aromatic profiles, stable isotope ratios, and essential oil yield are established for each sample. This study confirms the existence of multiple chemotypes and, for the first time, to the author's best knowledge, establishes stable isotope ratios for O. campechianum essential oil, which proves a useful tool in further investigating plant metabolism and determining essential oil authenticity.

Chemical composition and larvicidal activity of the essential oil of Pimenta dioica leaves / Composición química y actividad larvicida del aceite esencial de hojas de Pimenta dioica

In this study, we investigated the main constituent, the predominant class and biological activity of the essential oil extracted from the leaves of Pimenta dioica and the pattern of the major constituent against larvae in the third stage of Aedes aegypti. For this reason, we extracted the oil by hydrodistillation, identified its components by gas chromatography coupled with mass spectrometry (GC/MS) and calculated the lethal concentration (LC50) of the larvicidal activity using the Reed-Muench method. The results show that the oil consists mainly of eugenol, in which the phenylpropanoid class predominated and the lethal concentration, LC50, was 38.86 µg mL-1at a confidence level of 2.25 µg mL-1, while the eugenol standard presented LC5079.75 µg mL-1at a confidence level of 2.10 µg mL-1. Given the facts, we conclude that the oil is more active than the standard and that it has the potential to replace chemical larvicides.

En este estudio, investigamos el constituyente principal, la clase predominante y la actividad biológica del aceite esencial extraído de las hojas de Pimenta dioica y el patrón del constituyente principal contra las larvas en la tercera etapa de Aedes aegypti. Por este motivo, extrajimos el aceite por hidrodestilación, identificamos sus componentes mediante cromatografía de gases acoplada a espectrometría de masas (GC/MS) y calculamos la concentración letal (CL50) de la actividad larvicida mediante el método Reed-Muench. Los resultados muestran que el aceite está constituido principalmente por eugenol, en el que predominó la clase fenilpropanoide y la concentración letal, CL50, fue de 38,86 µg.mL-1 a un nivel de confianza de 2,25 µg.mL-1, mientras que el estándar de eugenol presentó CL50 79,75 µg.mL -1 a un nivel de confianza de 2,10 µg.mL-1. Dados los hechos, concluimos que el aceite es más activo que el estándar y que tiene el potencial de reemplazar los larvicidas químicos.

Radical scavenging activity and metabolomic profiling study of ylang-ylang essential oils based on high-performance thin-layer chromatography and multivariate statistical analysis.

Ylang-ylang (YY) essential oil (EO) is distilled from the fresh-mature flowers of the Annonaceae family tropical tree Cananga odorata [Lam.] Hook. f. & Thomson, and is widely used in perfume and cosmetic industries for its fragrant character. Herein, two different metabolomic profiles obtained using high-performance thin-layer chromatography (HPTLC), applying different stains, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH·) and p-anisaldehyde, were used for discrimination of 52 YY samples across geographical origins and distillation grades. The first profile is developed using the DPPH· stain based on the radical scavenging activity (RSA) of YY EOs. Results of the HPTLC-DPPH· assay confirmed that RSA of YY EOs is in proportion to the length of distillation times. Major components contributing to the RSA of YY EOs were tentatively identified as germacrene D and α-farnesene, eugenol and linalool, by gas chromatography-mass spectrometry (GC-MS) and GC-flame ionisation detector (GC-FID). The second profile was developed using the general-purpose p-anisaldehyde stain based on the general chemical composition of YY EOs. Untargeted metabolomic discrimination of YY EOs from different geographical origins was performed based on the HPTLC-p-anisaldehyde profiles, followed by principal component analysis (PCA). A discrimination and prediction model for identification of YY distillation grade was developed using PCA and partial least squares regression (PLS) based on binned HPTLC-ultraviolet (254 nm) profiles, which was successfully applied to distillation grade determination of blended YY Complete EOs.

Development and validation of a rapid high-performance thin-layer chromatographic method for quantification of gallic acid, cinnamic acid, piperine, eugenol, and glycyrrhizin in Divya-Swasari-Vati, an ayurvedic medicine for respiratory ailments.

Divya-Swasari-Vati is a calcium containing polyherbal ayurvedic medicine prescribed for the lung-related ailments observed in the current pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 infections. The formulation is a unique quintessential blend of nine herbs cited in Ayurvedic texts for chronic cough and lung infection. Analytical standardization of herbal medicines is the pressing need of the hour to ascertain the quality compliance. This persuaded us to develop a simple, rapid, and selective high-performance thin-layer chromatographic method for Divya-Swasari-Vati quality standardization. The developed method was validated for the quantification of marker components, gallic acid, cinnamic acid, piperine, eugenol and glycyrrhizin, against reference standards in five different batches of Divya-Swasari-Vati. The analytes were identified by visualization at 254 nm, and by matching their retention factor with authentic standards. The developed method was validated as per the guidelines recommended by the International Council for Harmonization for parameters like, linearity, limit of detection, limit of quantification, accuracy, and precision. Therefore, the developed novel high-performance thin-layer chromatographic process could be employed for rapid standardization of Divya-Swasari-Vati and other related herbal formulation, which would aid in quality manufacturing and product development.

Growth Restriction of Rhizoctonia solani via Breakage of Intracellular Organelles Using Crude Extracts of Gallnut and Clove.

Plant diseases reduce crop yield and quality, hampering the development of agriculture. Fungicides, which restrict chemical synthesis in fungi, are the strongest controls for plant diseases. However, the harmful effects on the environment due to continued and uncontrolled utilization of fungicides have become a major challenge in recent years. Plant-sourced fungicides are a class of plant antibacterial substances or compounds that induce plant defenses. They can kill or inhibit the growth of target pathogens efficiently with no or low toxicity, they degrade readily, and do not prompt development of resistance, which has led to their widespread use. In this study, the growth inhibition effect of 24 plant-sourced ethanol extracts on rice sprigs was studied. Ethanol extract of gallnuts and cloves inhibited the growth of bacteria by up to 100%. Indoor toxicity measurement results showed that the gallnut and glove constituents inhibition reached 39.23 µg/mL and 18.82 µg/mL, respectively. Extract treated rice sprigs were dry and wrinkled. Gallnut caused intracellular swelling and breakage of mitochondria, disintegration of nuclei, aggregation of protoplasts, and complete degradation of organelles in hyphae and aggregation of cellular contents. Protection of Rhizoctonia solani viability reached 46.8% for gallnut and 37.88% for clove in water emulsions of 1000 µg/mL gallnut and clove in the presence of 0.1% Tween 80. The protection by gallnut was significantly stronger than that of clove. The data could inform the choice of plant-sourced fungicides for the comprehensive treatment of rice sprig disease. The studied extract effectively protected rice sprigs and could be a suitable alternative to commercially available chemical fungicides. Further optimized field trials are needed to effectively sterilize rice paddies.

Simultaneous Estimation of Cinnamaldehyde and Eugenol in Essential Oils and Traditional and Ultrasound-Assisted Extracts of Different Species of Cinnamon Using a Sustainable/Green HPTLC Technique.

A wide range of analytical techniques are reported for the determination of cinnamaldehyde (CCHO) and eugenol (EOH) in plant extracts and herbal formulations either alone or in combination. Nevertheless, sustainable/green analytical techniques for the estimation of CCHO and EOH either alone or in combination are scarce in the literature. Accordingly, the present research was carried out to establish a rapid, highly sensitive, and sustainable high-performance thin-layer chromatography (HPTLC) technique for the simultaneous estimation of CCHO and EOH in the traditional and ultrasound-assisted methanolic extracts of Cinnamomum zeylanicum,C. burmannii, and C. cassia and their essential oils. The simultaneous estimation of CCHO and EOH was performed through NP-18 silica gel 60 F254S HPTLC plates. The cyclohexane/ethyl acetate (90:10, v v-1) solvent system was optimized as the mobile phase for the simultaneous estimation of CCHO and EOH. The greenness score of the HPTLC technique was predicted using AGREE software. The entire analysis was carried out at a detection wavelength of 296 nm for CCHO and EOH. The sustainable HPTLC technique was observed as linear in the range 10-2000 ng band-1 for CCHO and EOH. The proposed technique was found to be highly sensitive, rapid, accurate, precise, and robust for the simultaneous estimation of CCHO and EOH. The content of CCHO in traditional methanolic extracts of C. zeylanicum,C. burmannii, and C. cassia was found to be 96.36, 118.49, and 114.18 mg g-1, respectively. However, the content of CCHO in ultrasound-assisted methanolic extracts of C. zeylanicum,C. burmannii, and C. cassia was found to be 111.57, 134.39, and 129.07 mg g-1, respectively. The content of CCHO in essential oils of C. zeylanicum,C. burmannii, and C. cassia was found to be 191.20, 214.24, and 202.09 mg g-1, respectively. The content of EOH in traditional methanolic extracts of C. zeylanicum,C. burmannii, and C. cassia was found to be 73.38, 165.41, and 109.10 mg g-1, respectively. However, the content of EOH in ultrasound-assisted methanolic extracts of C. zeylanicum,C. burmannii, and C. cassia was found to be 87.20, 218.09, and 121.85 mg g-1, respectively. The content of EOH in essential oils of C. zeylanicum,C. burmannii, and C. cassia was found to be 61.26, 79.21, and 69.02 mg g-1, respectively. The amounts of CCHO and EOH were found to be significantly higher in ultrasound-assisted extracts of all species compared to its traditional extraction and hence ultrasound extraction has been proposed as a superior technique for the extraction of CCHO and EOH. The AGREE analytical score of the present analytical technique was predicted as 0.75, suggesting excellent greenness profile of the proposed analytical technique. Based on all these observations and results, the proposed sustainable HPTLC technique can be successfully used for the simultaneous estimation of CCHO and EOH in different plant extracts and herbal products.

Electrospray mass-spectrometry guided target isolation of neolignans from Nectandra leucantha (Lauraceae) by high performance- and spiral-coil countercurrent chromatography.

Nectandra leucantha (Lauraceae) is a tree indigenous to the tropical Atlantic forests of Brazil, one of the most biodiverse flora hotspots worldwide. This plant species contains high concentrations of neolignan and dehydrodieugenol derivatives that express significant in-vitro activities against various parasite strains. These activities are however responsible for severe tropical human infections, such as Leishmaniasis (Leishmania spp.) and Chagas disease (Trypanosoma cruzi), which have been classified by the World Health Organization (WHO) as Neglected Tropical Diseases (NTDs). In order to optimize the isolation process for these target metabolites, n-hexane extract of the leaves was separated by means of semi-preparative high performance countercurrent chromatography (HPCCC) and scale-up spiral-coil countercurrent chromatography (sp-CCC) systems. Several biphasic solvent mixtures were evaluated for their partitioning effects on neolignans, resulting in the selection of an optimized system n-hexane - ethylacetate - methanol - water (7:3:7:3, v/v/v/v). The chromatographic experiments on the HPCCC and sp-CCC were run in the head-to-tail mode with 500 mg and 16 g injections, respectively. For specific and multiple metabolite detection, the recovered CCC-fractions were off-line injected, in the sequence of recovery, to an electrospray mass-spectrometry (ESI-MS/MS) device. A projection of the single ion traces of the target compounds, in the positive ionization mode at a scan range of m/z 100-1500, located chromatographic areas where the co-elution effects occurred and pure target metabolites were present. Five major target neolignans were specifically detected, which enabled the accurate pooling of CCC-fractions for an optimum recovery of the metabolites. The direct comparison of the performance characteristics of the two CCC-devices, with very different mechanical designs was achieved by the conversion of the time axis into a partition ratio (KD) separation scale. As a result, the compound specific KD-elution values of the target neolignan were determined in high precision, while the comparison of the calculated separation factor (α) and resolution factor (RS) values revealed a superior separation performance for the HPCCC system. Also, the reproducibility of detected metabolites in the two CCC experiments was confirmed by small variations (ΔKD ±0.1). Neolignan target compounds with anti-parasite activities were successfully isolated in the 100 mg to 4 g range in a single lab-scale countercurrent chromatographic process step.

Simultaneous determination of fourteen main active components in Gumiganghwal-tang tablet by using a newly developed UPLC-ESI-MS/MS method.

The purpose of this study was to develop a method for simultaneous analysis of fourteen major active components in Gumiganghwal-tang tablet widely prescribed for cold related diseases using UPLC-ESI-MS/MS. Twelve of these 14 components were separated using 0.1% formic acid and acetonitrile as a mobile phase by gradient elution at a flow rate of 0.3 mL/min equipped with a KINETEX C18 column (2.1 × 50 mm, 1.7 µm). The remaining two components were separated using 10 mM aqueous ammonium formate containing 0.01% formic acid and acetonitrile as a mobile phase by gradient elution at a flow rate of 0.2 mL/min equipped with an Inertsil C8-3 column (2.1 × 100 mm, 2.0 µm). Quantitation of this analysis was performed on a triple quadrupole mass spectrometer using electrospray ionization technique operating in multiple reaction monitoring mode. Full validation of the analysis method was carried out, including its linearity, selectivity, sensitivity, precision, accuracy, recovery, and stability. Chromatograms showed high resolution, sensitivity, and selectivity without interference by impurities. Calibration curves of all 14 components ranged from 0.5 to 1000 ng/mL, displaying excellent linearity (correlation coefficients >0.99). The relative standard deviations (RSD) of intra- and inter-day were <11.75%. Recoveries were within the range 95.41-103.24% (RSD value of 1.62-9.09%). These results demonstrate that the developed method is simple, rapid, reliable, specific, accurate, and sensitive for the quantification of bioactive components of Gumiganghwal-tang. The developed method was successfully applied to the analysis of Gumiganghwal-tang tablet. The developed UPLC-ESI-MS/MS method could be useful not only for quality control, but also for effectiveness and safety evaluation of Gumiganghwal-tang tablet.

Levels of methyleugenol and eugenol in instant herbal beverages available on the Indonesian market and related risk assessment.

The presence and accompanying risks of methyleugenol and eugenol in herbal beverages available on the Indonesian market were evaluated. Methyleugenol was detected in 49 out of 114 samples, at levels amounting to 2.6-443.7 µg/g, while 4 samples contained eugenol at 21.4-101.2 µg/g. The EDI resulting from drinking these preparations amounted to 0.1-51.2 µg/kg bw/day and 1.1-3.3 µg/kg bw/day, respectively for samples targeted at adults and children. A BMDL10 value of 22.2 mg/kg bw/day for methyleugenol was defined using literature data and model averaging. MOE values were below 10,000 for 46 samples (40.4%), indicating a priority for risk management when assuming daily lifelong consumption, while the EDI for 4 samples containing eugenol did not exceed the ADI of 2.5 mg/kg bw thus did not raise a concern for human health. Using Haber's rule to correct for less than lifetime exposure, consumption of methyleugenol via these beverages would be of low concern when consumed for less than 2 weeks/year during a lifetime. This conclusion holds for herbal beverages collected by targeted sampling, not for all herbal beverages on the Indonesian market. The study provides data that can support establishment of a maximum permitted level (MPL) for methyleugenol in herbal beverages in Indonesia.

Effects of edible coating containing nano-emulsion of Aloe vera and eugenol on the physicochemical properties of shrimp during cold storage.

BACKGROUND: Shrimp is nowadays recognized as a rich source of proteins and omega-3 fatty acids. Edible nano-emulsion coatings containing eugenol, as an antioxidant agent, and Aloe vera, as a functional compound, were prepared for the storage of pink shrimp over 7 days at 277 K. Samples of the nano-emulsion were prepared under ultrasonication using 0, 10 and 20 g L-1 of Aloe vera as well as 0, 15 and 30 mL L-1 of eugenol along with Tween 80. RESULTS: Results indicated that the low pH of Aloe vera reduced that of the nano-emulsions while the particle size and turbidity increased with increasing Aloe vera concentration. Moreover, both colour and antioxidant activity of the nano-emulsions were significantly affected by eugenol and Aloe vera concentrations (p < 0.05). Increasing eugenol concentration led to increased nano-emulsion pickup but to reduced lightness. Higher concentrations of Aloe vera significantly (p < 0.05) decreased drip loss, cooking loss, pH rise and oxidation rates but enhanced hardness in the shrimp samples. CONCLUSIONS: The best results were recorded for the nano-emulsion coating containing 30 mL L-1 of eugenol and 20 g L-1 of Aloe vera. The nano-emulsion was successfully able to upgrade shrimp quality over 7 days of cold storage. © 2019 Society of Chemical Industry.

Chemometric analysis of NMR and GC datasets for chemotype characterization of essential oils from different species of Ocimum.

The genus Ocimum (Labiatae) comprises 30 species found in tropical and subtropical regions of the planet, of which species O. basilicum L. and O. gratissimum are widely used in food and traditional medicine. Phytochemical studies on Ocimum have revealed a number of essential oil chemotypes, for example, eugenol, methyl chavicol, linalool, and methyl cinnamate. Since essential oils are commercially assessed according to their content, the aim of this study was to develop a simple and precise method for their qualitative and quantitative analysis using NMR spectroscopy combined with chemometrics. Seven essential oils from different species of Ocimum, an unknown sample, and a commercial sample were evaluated and the results compared to those from established and precise GC-MS and GC-FID methods. Chemometric evaluation from both 1H NMR and GC-MS data revealed three chemotypes: eugenol for O. gratissimum, O. micranthum, and O. tenuiflorum; estragole for O. basilicum, O. basilicum var. purpuracens, and O. selloi; and methyl cinnamate for O. americanum. The unknown and commercial species were classified as cinnamate and eugenol chemotypes, respectively. Despite the corroborating results, the chemometric analysis revealed the higher robustness (better adjustment) of the 1H NMR model compared to the GC-MS method in terms of certain statistical parameters. The 1H NMR method allows for the detection and quantification of organic compounds in a complex mixture without the need for certified standard compounds. Although GC-MS and GC-FID were able to detect five compounds not observed by NMR spectroscopy, the four most important metabolites (eugenol, estragole, methyl cinnamate, and eucalyptol) were more readily detected and quantified by 1H NMR.

Quantification through TLC-densitometric analysis, repellency and anticholinesterase activity of the homemade extract of Indian cloves.

The rise of the mosquitoes-transmitted diseases, like dengue, zika and chikungunya in Brazil in the last years has increased concerns on protection against mosquitoes bites. However, the prohibitive prices of the commercially available repellents for the majority of the Brazilian population has provoked a search for cheaper solutions, like the use of the homemade ethanolic extract of Indian clove (Syzygium aromaticum L.) as repellent, which has been reported as quite efficient by the local press. In order to verify this, we performed here the quantification of the main components of this extract through high-performance thin-layer chromatography (HPTLC)-densitometry and evaluated its efficiency as a repellent and its acetylcholinesterase (AChE) inhibition capacity. Our results have proved HPTLC-densitometry as an efficient and appropriate method for this quantification and confirmed the repellency activity, as well as its capacity of AChE inhibition.

Characterization of Essential Oil Composition in Different Basil Species and Pot Cultures by a GC-MS Method.

Basil (Ocimum L.) species are used as medicinal plants due to their essential oils exhibiting specific biological activity. The present work demonstrated that both the variety and season/conditions of cultivation had a significant effect on (i) the produced amount (extraction yield), (ii) qualitative, as well as (iii) quantitative profile of basil essential oil. Among studied basil varieties, a new variety, 'Mánes', was characterized for the first time. Based on our quantitative evaluation of GC-MS profiles, the following chemotypes and average concentrations of a main component were detected in the studied basil varieties: 'Ohre', 'Lettuce Leaf', 'Purple Opaal', 'Dark Green' (linalool, 5.99, 2.49, 2.34, 2.01 mg/mL, respectively), and 'Mammolo Genovese', 'Mánes', 'Red Rubin' (eucalyptol, 1.34, 0.96, 0.76 mg/mL, respectively). At the same time, when considering other compounds identified in GC-MS profiles, all the studied varieties, except from 'Lettuce Leaf', were methyl eugenol-rich with a strong dependence of the eugenol:methyl eugenol ratio on the seasonal changes (mainly solar irradiation, but also temperature and relative humidity). More complex and/or variable (depending on the season and cultivation) chemotypes were observed with 'Lettuce Leaf' (plus estragole, 2.27 mg/mL), 'Dark Green' (plus eucalyptol, 1.36 mg/mL), 'Mammolo Genovese' (plus eugenol, 1.19 mg/mL), 'Red Rubin' (plus linalool and eugenol, 0.46 and 0.56 mg/mL, respectively), and 'Mánes' (plus linalool and eugenol, 0.58 and 0.40 mg/mL, respectively). When considering superior extraction yield (ca. 17 mL·kg-1, i.e., two to five times higher than other examined varieties) and consistent amounts (yields) of essential oil when comparing inter-seasonal or inter-year data (RSD and inter-year difference in mean yield values ˂2.5%), this new basil variety is very promising for use in the pharmaceutical, food, and cosmetic industries.

Phytochemical study and biological effects of the essential oil of Fraxinus dimorpha Coss & Durieu §.

The present study describes the phytochemical study, antioxidant and antimicrobial activities of Fraxinus dimorpha essential oil, obtained from the leaves collected in the High Atlas Mountains. Forty compounds representing 86.2% with (E)-nerolidol as a major constituent and 29 compounds corresponding to 80.3% with eugenol as main components were identified from Ait M'hamed and from Siti Fadma, respectively. The F. dimorpha essential oil presents IC50 using DPPH varying from 5.33 to 6.03 mg/mL and EC50 using FRAP varying from 0.83 to 1.21 mg/mL. The antimicrobial activity of the oil was evaluated for ten microorganisms showed that the oil had a moderate potential activity. Fungal strains are more sensitive to the investigated oils, with a MIC varied between 1.8 and 3.8 mg/mL.

GC-MS method validation and levels of methyl eugenol in a diverse range of tea tree (Melaleuca alternifolia) oils.

Tea tree oil distilled from Melaleuca alternifolia has widespread use in the cosmetic industry as an antimicrobial as well as for other functions in topical products. Concerns were first raised by the European Commission's Scientific Committee on Consumer Products in 2004 about the level of the potentially carcinogenic phenylpropanoid compound methyl eugenol in tea tree oil. Limits on oil content in different types of cosmetic products were set based on a reported upper level of 0.9% methyl eugenol in the oil. A previous publication indicated that these levels were based on oil from a Melaleuca species not used in the commercial production of oil. Even the highest recorded levels in Melaleuca alternifolia, the overwhelmingly most common species used, were ∼15 times less than this, meaning that more oil could be safely used in the products. The current study, including details on methodology and reproducibility, extends that work across a suite of 57 plantation-sourced oils from a range of geographical locations and production years, as well as many Australian and international commercial oils. Lower levels of methyl eugenol in oils of known provenance were confirmed, with a recorded range of 160-552 ppm and a mean of 337 ppm. Analysis of variance showed methyl eugenol levels in Australian plantation oils to be correlated to the geographical region but not to the year of production. Average methyl eugenol levels in commercial oils were significantly lower, and these samples were divided into an authentic group and a group that were suspected of being adulterated based on an independent test. Authentic commercial oils had similar levels of methyl eugenol to Australian provenance material, whilst the oils classed as suspect had significantly lower levels.

Identification of Aroma-active Compounds in Essential Oil from Uncaria Hook by Gas Chromatography- Mass Spectrometry and Gas Chromatography-Olfactometry.

The chemical composition of essential oil extracted from Uncaria Hook ("Chotoko" in Japanese), the branch with curved hook of the herbal medicine Uncaria rhynchophylla has been investigated by GC and GC-MS analyses. Eighty-four compounds, representing 90.8% of the total content was identified in oil obtained from Uncaria Hook. The main components i were (E)-cinnamaldehyde (13.4%), α-copaene (8.0%), methyl eugenol (6.8%), δ-cadinene (5.3%), and curcumene (3.6%). The important key aroma-active compounds in the oil were detected by gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA), using the flavor dilution (FD) factor to express the odor potency of each compounds. Furthermore, the odor activity value (OAV) has been used as a measure of the relative contribution of each compound to the aroma of the Uncaria Hook oil. The GC-O and AEDA results showed that α-copaene (FD = 4, OAV = 4376), (E)-linalool oxide (FD = 64, OAV = 9.1), and methyl eugenol (FD = 64, OAV = 29) contributed to the woody and spicy odor of Uncaria Hook oil, whereas furfural (FD = 8, OAV = 4808) contributed to its sweet odor. These results warrant further investigations of the application of essential oil from Uncaria Hook in the phytochemical and medicinal fields.

Monitoring of sixteen fragrance allergens and two polycyclic musks in wastewater treatment plants by solid phase microextraction coupled to gas chromatography.

A methodology based on headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) determination was developed for the monitoring and evaluation of the removal efficiency of 16 common fragrance allergens and two polycyclic musks in wastewater treatment plants (WWTPs). An experimental design with a full factorial model was applied to evaluate the effects of the experimental parameters on the extraction (e.g., salt content, time and extraction temperature). After determining the optimum conditions (2.4 g NaCl, 45 min at 90 °C), an external calibration was performed and quality parameters of the proposed method were evaluated. Method detection limits in the range of 0.01-1.7 µg L(-1) were obtained. Satisfactory inter-day precision values between 4% and 23% (n=5) were obtained for most compounds. The method was applied to the monitoring of the target analytes in samples from two WWTPs. Seven target compounds were detected at the primary effluent of both plants at µg L(-1) levels. Limonene, linalool and eugenol were quantitatively eliminated during the secondary treatments of both WWTPs, while lilial, benzyl salicylate, galaxolide, and tonalide were still detected at the effluent waters.