Essential Oils: Chemistry and Food Applications.

In recent years, the crucial role played by essential oils in various areas such as health, cosmetics, crop protection, and food industries has been increasingly recognized [...].

Stability of Cocaine, Opiates, and Metabolites in Dried Saliva Spots.

Drug abuse still represents a global problem, and it is associated with an increased risk of diseases, injuries, and deaths. Cocaine (COC) and opiates are the most abused drugs and account for a significant number of fatalities. Therefore, it is important to develop methods capable of effectively identifying and quantifying these substances. The present study aims to evaluate the long-term stability of COC, ecgonine methylester (EME), benzoylecgonine (BEG), cocaethylene (COET), norcocaine (NCOC), morphine (MOR), codeine (COD) and 6-monoacetylmorphine (6-MAM) in oral fluid samples. The analytes of interest were isolated from the matrix (50 µL) using the dried saliva spots (DSS) sampling approach and were subsequently analyzed by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). The parameters that could influence the stability of the target compounds were studied, and these were storage temperature, light, use of preservatives (and respective concentrations), and time. The effects of each parameter were evaluated using the design of experiments (DOE) approach. The stability of the target analytes was improved when the DSS were stored at room temperature, in the presence of light and using 1% sodium fluoride. The best conditions were then adopted for the DSS storage and long-term stability was assessed. COD was only stable for 1 day, EME was stable for 3 days, COC, COET, NCOC and 6-MAM were stable for 7 days, MOR for 14 days and BEG remained stable throughout the study (136 days). This is the first study that evaluates the stability of these compounds in oral fluid samples after application in DSS cards, and optimizes the conditions in order to improve their stability.

Total Fat Gravimetric Method Workflow in Portuguese Olives Using Closed-Vessel Microwave-Assisted Extraction (MAE).

A simple and rapid method for the quantitation of total fat in olive samples is designed, evaluated, and presented. This method is based on an innovative closed-vessel microwave-assisted extraction (MAE) technique. A method was designed for olives, and some figures of merits were evaluated: limit of detection (LOD), limit of quantification (LOQ) and expanded uncertainty (U). The data obtained in these experiences show that the workflow of the MAE method in a closed container is statistically equivalent to the other two methods, showing in this case better performance indicators (LOD = 0.02%, LOQ = 0.06%, and U = 15%). In addition, it is also demonstrated that the complete MAE method workflow allows the determination of total fat in a maximum of 12 analyses simultaneously for about 100 min in each run, which is the capacity of the rotor. This is a much better productivity when compared to the traditional Soxhlet-based method. Considering the sample workflow, the closed-vessel MAE method greatly simplifies sample handling, therefore minimizing sample loss during sample preparation and reducing analysis time. When MAE is compared to NIR-based methods, the advantage comes from there being no need for any type of calibration in the sample matrix. The MAE method itself can be used to determine the reference value for NIR calibration purposes. The results obtained for CRM using MAE were equivalent to the ones shown on the certificate.

Correction: Simão, A.Y., et al. Evaluation of the Cytotoxicity of Ayahuasca Beverages. Molecules 2020, 25, 5594.

This paper [...].

Effect of essential oils against acaricide-susceptible and acaricide-resistant Rhipicephalus ticks.

The indiscriminate use of acaricides is a problem worldwide and has increased the selection of acaricide-resistant tick populations. The goal of this study was to evaluate the acaricide effects of two essential oils (from Schinus molle and Bulnesia sarmientoi) using the larval immersion test on three Rhipicephalus tick species. Rhipicephalus evertsi, Rhipicephalus appendiculatus and Rhipicephalus pulchelus ticks collected in Kenya, without history of acaricide exposure, were tested, as well as individuals from two populations of Rhipicephalus microplus (with or without history of acaricide exposure), for comparison. The sample most resistant to the treatments was a population of R. microplus with previous acaricide exposure, whereas the least tolerant sample was a strain of the same species that never had contact with acaricides (Porto Alegre strain). Interestingly, the field tick samples without previous acaricide exposure responded to essential oils with a mortality profile resembling that observed in the acaricide-resistant R. microplus field population, and not the susceptible Porto Alegre strain. The essential oil of B. sarmientoi and its two components tested (guaiol and bulnesol) caused the highest mortality rates in the tested species and are potential molecules for future studies on control methods against these species.

Evaluation of the Cytotoxicity of Ayahuasca Beverages.

Ayahuasca is a beverage consumed at shamanic ceremonies and currently has gained popularity on recreational scenarios. It contains beta-carboline alkaloids and N,N-dimethyltryptamine, which possesses hallucinogenic effects. Only a few studies have elicited the psychoactive effects and the dose of such compounds on neurological dopaminergic cells or animals. In this work, we aimed to study the cytotoxic effects of these compounds present in ayahuasca beverages and on five different teas (Banisteriopsis caapi, Psychotria viridis, Peganum harmala, Mimosa tenuiflora and Dc Ab (commercial name)) preparations on dopaminergic immortalized cell lines. Moreover, a characterization of the derivative alkaloids was also performed. All the extracts were characterized by chromatographic systems and the effect of those compounds in cell viability and total protein levels were analyzed in N27 dopaminergic neurons cell line. This is the first article where cytotoxicity of ayahuasca tea is studied on neurological dopaminergic cells. Overall, results showed that both cell viability and protein contents decreased when cells were exposed to the individual compounds, as well as to the teas and to the two mixtures based on the traditional ayahuasca beverages.

Determination of antipsychotic drugs in oral fluid using dried saliva spots by gas chromatography-tandem mass spectrometry.

The present work describes the optimization and validation of an analytical method for the determination of six antipsychotic drugs (chlorpromazine, levomepromazine, cyamemazine, clozapine, haloperidol, and quetiapine) in oral fluid samples after solvent extraction from dried saliva spots, by gas chromatography coupled to tandem mass spectrometry. The method was fully validated, and the included parameters were selectivity, linearity, limits of quantification, precision and accuracy, stability, and recovery. The method was linear for all compounds from 10 to 400 ng/mL, except for haloperidol (5-100 ng/mL), presenting coefficients of determination higher than 0.99. Inter- and intra-day precision and accuracy were in conformity with the criteria usually seen in bioanalytical method validation; i.e., coefficients of variation were lower than 15% and an accuracy of 15% or better for all studied drugs. The recoveries obtained with this miniaturized technique ranged from 63 to 97%. The herein described method is the first to be reported using the dried saliva spots approach for the analysis of these antypshychotic drugs, proving great sensitivity apart from its simple and fast procedure. The method was considered a good alternative to the conventional techniques to be applied in clinical and toxicological analyses, even more taking into account the extremely low sample volume used (50 µL). Graphical abstract.

Determination of amphetamine-type stimulants in urine samples using microextraction by packed sorbent and gas chromatography-mass spectrometry.

The aim of this work was the development, optimization and full validation of a method applying microextraction by packed sorbent (MEPS) coupled to gas chromatography-mass spectrometry (GC-MS) to determine amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxyethylmethamphetamine (MDMA), 3,4-methylenedioxy-N-methyl-α-ethylfenilethylamine (MBDB), and 3,4-methylenedioxy-N-ethylamphetamine (MDE) in urine samples. Using 200 µL of sample, the MEPS procedure was optimized concerning type of sorbent, sample dilution, number of strokes, activation of the ion exchange mechanism and composition of both washing and elution solvents. The method was fully validated according to the Food and Drug Administration and the Scientific Working Group of Forensic Toxicology guidelines for the validation of bioanalytical methods. The studied parameters included selectivity, calibration model and linearity, limits of detection and quantification, precision, accuracy, stability, dilution integrity and recoveries. Linearity was obtained in the range of 25-1000 ng/mL for MAMP, MBDB and MDE, 35-1000 ng/mL for AMP and MDMA, and 50-1000 ng/mL for MDA, with coefficients of determination (R2) >0.99 for all analytes. Both intra- and inter-day precision and accuracy were adequate, and coefficients of variation lower than 15% and mean relative errors (RE) within a range of ±15% of the theoretical concentrations were obtained for all compounds under study. Analyte recoveries ranged from 19 to 71%, allowing LLOQs ≤50 ng/mL.

Antioxidant Activity of Carvone and Derivatives against Superoxide Ion.

Carvone has corroborated its versatility as starting material for building blocks synthesis in organic chemistry, being achieved a new chiral lactone. It has been done a study on the antioxidant activity against superoxide of carvone and a chloro derivative that show the potent activity of the natural product (R)-carvone, 1.

Antibacterial and antioxidant activity of Portuguese Lavandula luisieri (Rozeira) Rivas-Martinez and its relation with their chemical composition.

Lavandula luisieri (Rozeira) Rivas-Martinez is an endemic aromatic Labiatae the Iberian Peninsula, common in semi-arid regions of southern Portugal and southwestern Spain, that produces an active antibacterial essential oil from the leaves and flowers. This work presents the study of the chemical variation in various stages of growth of leaves and flowers of L. luisieri. It has been found that the essential oils are mainly constituted by 1,8-cineol, camphor, linalool and trans-α-necrodil acetate. It was also studied the total phenol content and the antioxidant activity on leaves and flowers. The ethanol extraction from de leaves contents the highest total phenol, important factor for the antioxidant activity of the plant, extract. It has been studied too, the antibacterial activity against Escherichia coli, Salmonella spp. and Staphylococcus aureus. In accordance with the obtained results, the antibacterial activities stand out against Staphylococcus, of the oil of L. luisieri (leaves and flowers).

Iodine, a Mild Reagent for the Aromatization of Terpenoids.

Efficient procedures based on the use of iodine for the aromatization of a series of terpenoids possessing diene and homoallylic or allylic alcohol functionalities are described. Different examples are reported as a proof-of-concept study. Furthermore, iodine also proved to mediate the dehydrogenation of testosterone.

Hydrotalcite catalysis for the synthesis of new chiral building blocks.

The use of hydrotalcites for the synthesis of two chiral building blocks in a simple way is described as a new and green methodology. The synthesis of these compounds implies a regioselective Baeyer-Villiger reaction in a very selective way with ulterior opening and lactonisation. This methodology should be considered green for the use of hydrogen peroxide as the only oxidant and hydrotalcites as the catalyst, and because no residues are produced apart from water. The procedure is very adequate for using in gram scale, in order to increase the value of the obtained compounds. The conditions are excellent and can be applied for nonstable compounds, as they are very mild. The synthesised compounds are magnific starting materials for the synthesis of biologically active or natural compounds. The use of a cheap, commercial and chiral compound as carvone disposable in both enantiomeric forms adds an extra value to this methodology.

Synergistic antibacterial activity of the essential oil of aguaribay (Schinus molle L.).

Schinus molle L. (aguaribay, aroeira-falsa, "molle", family Anacardiaceae), a native of South America, produces an active antibacterial essential oil extracted from the leaves and fruits. This work reports a complete study of its chemical composition and determines the antibacterial activity of Schinus molle L. essential oil and its main components. The results showed that the crude extract essential oil has a potent antibacterial effect on Staphylococcus aureus ATCC 25923, a strong/moderate effect on Escherichia coli ATCC 25922 and moderate/weak one on Pseudomonas aeruginosa ATCC 27853.

Diterpene lactones with labdane, halimane and clerodane frameworks.

The labdane, halimane and clerodane type diterpenoids are compounds that have been isolated in plants of several families. These molecules and their derivatives with a lactone group on the side chain or on the decaline system, have a great interest because of their biological properties as insect antifeedant, antiviral, cytotoxic and trypanocidal. The scope of this review is lactones diterpenoids with labdane, halimane and clerodane frameworks.

New phenolic esters from the resinous exudate of Haplopappus taeda.

Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.

From labdanes to drimanes. Degradation of the side chain of dihydrozamoranic acid.

A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been devised, giving an advanced intermediate, compound 14, useful for the synthesis of insect antifeedants such as warburganal and polygodial.