Chemical composition, antioxidant, and antimicrobial activities of six commercial essential oils.

Essential oils (EOs) and their components extracted from medicinal and aromatic plants are used in several areas, such as perfumery and chemical, cosmetic, food, and pharmaceutical industries. Considering the different applications of EOs, this work aimed to screen the composition and the bioactivities properties of the EOs of Foeniculum vulgare, Helichrysum stoechas, Mentha pulegium, Pinus pinaster, Ruta graveolens, and Thymus mastichina. Gas chromatography-mass spectrometry revealed the presence of different compounds in EOs F. vulgare (12), H. stoechas (27), M. pulegium (8), P. pinaster (24), R. graveolens (8), and T. mastichina (16). All the EOs showed antioxidant activity acting through inhibition of lipid peroxidation, while only two EOs (H. stoechas and M. pulegium) scavenged the free radicals of DPPH. Mentha pulegium and T. mastichina EOs showed the strongest antimicrobial activity. Also, the effect on the fibroblast's viability was directly proportional to the EOs concentration, and the highest cytotoxic effect was registered with R. graveolens EO. The present study revealed significant bioactive properties of different EOs, highlighting M. pulegium and T. mastichina EOs to be considered in further studies for potential use in the food and pharmaceutical industries, due to their antioxidant and antimicrobial properties.

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.

Solvent-Free Microwave Extraction of Thymus mastichina Essential Oil: Influence on Their Chemical Composition and on the Antioxidant and Antimicrobial Activities.

Solvent-free microwave extraction (SFME) is a combination of microwave heating and dry distillation performed at atmospheric pressure without the addition of water or organic solvents that has been proposed as a green method for the extraction of essential oils from aromatic and medicinal herbs. In this work, SFME and the conventional techniques of steam distillation (SD) and hydrodistillation (HD) were compared with respect to the extraction and antioxidant and antimicrobial activities of Thymus mastichina essential oil. The main constituent of essential oils obtained using different methods was 1,8-cineole (eucalyptol). The results showed that the essential oils extracted by means of SFME in 30 min were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained using conventional HD over 120 min. In addition, SFME generates less waste and less solvent, consumes less energy, and provides a higher yield for a shorter extraction time, which is advantageous for the extraction of the T. mastichina essential oil compared to SD. The antioxidant and antimicrobial activities of the T. mastichina essential oil obtained from either SFME or conventional extraction methods (SD or HD) showed a similar pattern. Large-scale experiments using this SFME procedure showed a potential industrial application.

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).

Antimicrobial activity and chemical composition of the essential oils of Portuguese Foeniculum vulgare fruits.

The aim of this study was to investigate the chemical composition and antimicrobial activity of essential oils obtained by hydrodistillation from fruits of six fennel accessions collected from wild populations occurring in the centre and south of Portugal. Composition of essential oils was established by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The obtained yields of the essential oils were found to vary greatly in the range of 1.1 to 2.9% (v/w) and the chemical composition varied with the region of collection. A total of 16 compounds were identified. The main compounds were fenchone (16.9 - 34.7%), estragole (2.5 - 66.0%) and trans-anethole (7.9 - 77.7%). The percentages of these three main compounds were used to determine the relationship between the different oil samples and to group them into four different chemotypes: anethole/fenchone; anethole; estragole and anethole/estragole. Antifungal activity of essential oils was evaluated against six food spoilage fungi: Aspergillus niger, A. japonicus, A. oryzae, Fusarium oxysporum, Rhizophus oryzae and R. stolonifer. Antibacterial activity was assessed against three Gram-positive strains: Enterococcus faecalis ATCC 29212, Staphylococcus epidermidis ATCC 12228 and S. aureus ATCC 28213; and against six Gram-negative strains: Escherichia coli ATCC 25922; Morganella morganii LFG 08; Proteus mirabilis LFG 04; Salmonella enteritidis LFG 05; S. entiritidis serovar typhimurium LFG 06 and Pseudomonas aeruginosa ATCC 27853 by the disc diffusion agar method; the minimal inhibitory concentration (MIC) was determined using the broth macro-dilution method. The MIC values varied from 62.5 (E. coli ATCC 25922) to 2000 µmL (P. aeruginosa ATCC 27853).

Depresión y ansiedad durante el aislamiento obligatorio por el COVID-19 en Lima Metropolitana / Depression and anxiety during the mandatory isolation period due to COVID-19 in Lima Metropolitan Area

Resumen Antecedentes la implementación de medidas de salud pública como la cuarentena o el aislamiento son estrategias útiles para el control de una enfermedad; no obstante, también traen consecuencias sobre la salud mental. Objetivos: describir la prevalencia de síntomas de ansiedad y depresión en adultos de Lima Metropolitana, durante el periodo de aislamiento social en respuesta a la pandemia del COVID-19. Método: se utilizaron ítems de la Escala de Ansiedad de Lima (EAL-20) y de la Escala de Psicopatología Depresiva (EPD-6) en una muestra de 565 adultos que residen en Lima Metropolitana durante el Estado de Emergencia Sanitaria. Resultados: se identificó la prevalencia de síntomas relacionados a la ansiedad y depresión. Además, se encontraron diferencias en función del sexo, edad, nivel educativo, y la modalidad del trabajo o estudio. Conclusiones: el aislamiento obligatorio implica la prevalencia de síntomas de ansiedad y depresión en adultos de Lima Metropolitana, los cuales se manifiestan de diferentes formas al considerar variables sociodemográficas. Esto es congruente con estudios a nivel internacional, por lo que deberían considerarse al tomar decisiones ligadas a políticas públicas de salud.

Abstract Background :the implementation of public health measures such as quarantines and isolation is a useful strategy for disease control; nonetheless, said measures may also have consequences on mental health. Objectives: to describe the prevalence of depression and anxiety symptoms in adults living in Lima Metropolitan Area during the social isolation period due to the COVID-19 pandemic. Method: items from the Lima Anxiety Scale (EAL-20) and the Depressive Psychopathology Scale (EPD-6) were used in a sample of 565 adults living in Lima Metropolitan Area during the health emergency. Results: prevalence of anxiety and depression symptoms were identified. Also, differences regarding sex, age, education level, and modality of work or study were found. Conclusions: the mandatory isolation period involves the prevalence of anxiety and depression symptoms in adults living in Lima Metropolitan Area. Such phenomena might occur in different ways according to the different sociodemographic variables. These findings are consistent with those from international studies; thus, they should be considered when making decisions related to public health policies.