Evaluación de combinaciones de aceites esenciales y aceites esenciales con hidrosoles sobre actividades antimicrobianas y antioxidantes]

International audienceContext: Essential oils (EO) are commonly extracted from plants by steam distillation in which an aqueous phase called hydrosol (HD) is obtained. Unlike EO, hydrosol studies have been limited despite the interest of the food, cosmetic and phytotherapeutic industries to find natural preservative alternatives to synthetic ones. Aims: To evaluate the in vitro antimicrobial and antioxidant efficacies of combinations of essential oils (EOs) and essential oils and hydrosols (HDs) of Lippia alba, Rosmarinus officinalis, and Thymus vulgaris. Methods: The EOs and HDs were characterized by gas chromatography with flame ionization detector and gas chromatography coupled with mass spectrometry. Then, they were screened against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus niger using the microdilution method for the four first strains and the agar diffusion method for Aspergillus niger. Antioxidant capacity was evaluated using ABTS method. Results: Interactions between essential oils, and essential oils and hydrosols were found to be as microbicide, and for the first time, antioxidant using the fractional inhibitory concentration. When compared with individual EOs, EO-EO combinations diminished the microbicide minimum concentration. Conclusions: The Thymus vulgaris EO-HD combination, in comparison with individual extracts, diminishes by four times the MBC against Escherichia coli and decrease by half their antioxidant capacity.Contexto: Los aceites esenciales (AEs) se extraen comúnmente de las plantas por destilación con arrastre de vapor en la que se obtiene una faseacuosa llamada hidrosol (HDs). A diferencia de los AE, los estudios de los HD han sido limitados a pesar del interés de las industrias alimentaria,cosmética y fitoterapéutica de encontrar alternativas naturales de conservación.Objetivos: Evaluar la eficacia antimicrobiana y antioxidante in vitro de las combinaciones de AEs, AEs e HDs de Lippia alba, Rosmarinus officinalis y Thymus vulgaris.Métodos: Los AEs e HDs fueron caracterizados por cromatografía de gases con detector de ionización en llama y cromatografía de gases acoplada a espectrometría de masas. Luego se realizaron pruebas de detección contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans y Aspergillus niger utilizando el método de microdilución para las cuatro primeras cepas y el método de difusión en agar para Aspergillus niger. La actividad antioxidante se evaluó utilizando el método ABTS.Resultados: Se encontró que las interacciones entre los aceites esenciales, aceites esenciales e hidrosoles eran microbicidas y, por primera vez,antioxidantes usando la concentración inhibidora fraccionada. Cuando se compararon con AEs individuales, las combinaciones AE-AEdisminuyeron la concentración microbicida mínima.Conclusiones La combinación de tomillo AE-HD; en comparación con los extractos individuales, disminuye en cuatro veces el MBC contraEscherichia coli y disminuye a la mitad su actividad antioxidante

Bioassay-guided fractionation in Anacardium excelsum (bert. & balb. ex kunth) skeels (anacardiaceae)

Anacardium excelsum is a tree between 15 and 50 meters high, with a thick trunk and is present in some departments of Colombia. Its nut-shaped fruits were used in the old Upar Valley by natives (Valledupar) to make Caracolí bread. Most research has been done at the forest level, but there are few phytochemical and biological activity studies. This bioguided work shows the application of antioxidant methods (ABTS+•, DPPH• and DMPD+•) in the search for active compounds present in the fraction and subfractions of greater activity. The antioxidant capacity was measured to the crude extract in ethanol and the antioxidant activity of the fractions in petroleum ether, dichloromethane, and ethanol-butanol of testa, tegument, flower, fruit, seed, bark, and leaf. Column Chromatography, Thin Layer Chromatography and Gas Chromatography coupled to Mass Spectrometry were performed on the petroleum ether fraction of testa with greater antioxidant capacity, finding the following compounds: 3- pentadec(en)il-phenol, 3-pentadecyl-phenol, 3-heptadeca(dien)il-phenol, 3-heptadec(en)ilphenol, 3-heptadecyl-phenol, 3-nonadec(en)il-phenol, ethyl ester of hexadecanoic acid, ethyl ester of heptadecanoic acid , ethyl ester of linolenic acid, hexadecanoic acid butyl ester, ethyl ether of octadecanoic acid, ethyl ester of (Z)-9-octadecenoic acid, ethyl ester of 9,12- octadecadienoic acid and ethyl ester of eicosanoic acid. The results indicate that Anacardium excelsum is a potential source of bioactive compounds.Incluye referencias bibliográfica

Effect of 6-Shogaol on the Glucose Uptake and Survival of HT1080 Fibrosarcoma Cells

Ginger is a plant that is native to southern China. In the last decade and research on the components of ginger has significantly increased; of these components, 6-shogaol exhibits the greatest potential antitumor capacity. However, the molecular mechanism through which 6-shogaol exerts its effects has not yet been elucidated. In this study, the effect of 6-shogaol on tumor cells that were derived from human fibrosarcoma (HT1080) was evaluated. Cell viability was determined by a (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT assay testing different concentrations of 6-shogaol (2.5–150 μM). Subsequently, the effect of 6-shogaol on reactive oxygen species (ROS) production, glucose uptake, and protein expression of the signaling pathway phosphatase and tensin homolog/ protein kinase B /mammalian target of rapamycin (PTEN/Akt/mTOR) was measured. 6-Shogaol reduced the viability of the tumor cells and caused an increase in ROS production, which was attenuated with the addition of N-acetylcysteine, and the recovery of cell viability was observed. The increase in ROS production in response to 6-shogaol was associated with cell death. Similarly, glucose uptake decreased with incremental concentrations of 6-shogaol, and an increase in the expression of mTOR-p and Akt-p proteins was observed; PTEN was active in all the treatments with 6-shogaol. Thus, the results suggest that cells activate uncontrolled signaling pathways, such as phosphoinositide 3-kinase (PI3K)/Akt/mTOR, among other alternative mechanisms of metabolic modulation and of survival in order to counteract the pro-oxidant effect of 6-shogaol and the decrease in glucose uptake. Interestingly, a differential response was observed when non-cancerous cells were treated with 6-shogaol

Evaluation of combinations of essential oils and essential oils with hydrosols on antimicrobial and antioxidant activities

Context: Essential oils (EO) are commonly extracted from plants by steam distillation in which an aqueous phase called hydrosol (HD) is obtained. Unlike EO, hydrosol studies have been limited despite the interest of the food, cosmetic and phytotherapeutic industries to find natural preservative alternatives to synthetic ones. Aims: To evaluate the in vitro antimicrobial and antioxidant efficacies of combinations of essential oils (EOs) and essential oils and hydrosols (HDs) of Lippia alba, Rosmarinus officinalis, and Thymus vulgaris. Methods: The EOs and HDs were characterized by gas chromatography with flame ionization detector and gas chromatography coupled with mass spectrometry. Then, they were screened against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus niger using the microdilution method for the four first strains and the agar diffusion method for Aspergillus niger. Antioxidant capacity was evaluated using ABTS method. Results: Interactions between essential oils, and essential oils and hydrosols were found to be as microbicide, and for the first time, antioxidant using the fractional inhibitory concentration. When compared with individual EOs, EO-EO combinations diminished the microbicide minimum concentration. Conclusions: The Thymus vulgaris EO-HD combination, in comparison with individual extracts, diminishes by four times the MBC against Escherichia coli and decrease by half their antioxidant capacity

Effect of ginger extract on membrane potential changes and AKT activation on a peroxide-induced oxidative stress cell model

Zingiber officinale is a type of Ginger used for the treatment of reactive oxygen species (ROS) associated diseases. Reports describe its use in cellular models, such as pancreatic and intestinal cancer cell lines. However, the biochemical bases of antitumor, anti-inflammatory and antioxidant activities have not yet been fully elucidated. The aim of this study was to evaluate in H2O2-induced oxidative stress the effect of ginger extract (GE) on HT1080 cell viability, ROS production, AKT activation, and mitochondrial membrane potential (ΔΨm). ROS production was measured by DHE probe. Results revealed a significant cell viability decrease with increasing GE concentrations. In addition, GE at 200 μg/ml and 400 μg/ml resulted in decreased ROS production compared with controls. Moreover, GE at 200 μg/ml concentration produced a significant increase in ΔΨm. In contrast, no difference in ΔΨm was observed compared to controls with GE at 400 μg/ml. In untreated HT1080 cells basal AKT activation was not observed. Conversely, treatment with 750 μM H2O2 led to Ser473 phosphorylation. Additionally, treatment with GE at 200 μg/ml decreased AKT activation. Reports in the literature describe GE biological activities; none the less, novel approaches to investigate intracellular changes resulting from GEs are described in this study. In conclusion, this study characterized GE induced intracellular changes, leading to changes in ΔΨm and signaling protein levels, such as AKT, and reduced cell viability. Keywords: Ginger extract, ROS, Viability, AKT protein, Mitochondrial membrane potentia

Preliminary Phytochemical Analysis of Berberis goudotii Triana & Planch. ex Wedd. (Berberidaceae) with Anticariogenic and Antiperiodontal Activities

Berberis goudotii is an endemic Colombian plant found in the paramo ecosystem. It has been used in food preparation and as a medicinal plant for diverse treatments. Additionally, it is used as a mouthwash to strengthen the gums and combat throat irritations and periodontitis. The present research evaluated Berberis goudotii aerial parts extract and fractions antimicrobial activities. Ultrasonic-assisted extraction was used to attain total ethanol-water extract. Solid-liquid fractionation was used to obtain hexane fraction. The residue was dispersed in water and liquid-liquid fractionation was carried-out to acquire dichloromethane, butanol and water fractions. Preliminary phytochemical analysis was performed on total extract and phenol, polyphenol, flavonoid, and proanthocyanidin, while tannin content was quantified. Antimicrobial activity assessment was performed by agar diffusion method using disks and wells employing Ceftazidime as a positive control against Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, Lactobacillus casei, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum. Antimicrobial activity was determined as relative percentage inhibition (RPI), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Phenols (92.5 ± 7.7 mg GA/10 g), polyphenols (87.7 ± 8.1 mg PG/10 g) and tannins (44.1 ± 4.3 mg PG/10 g) were among the highest secondary metabolites observed. Total extract presented an MBC of 1.0 µg/µL against cariogenic bacteria (Streptococcus mutans and Streptococcus sobrinus) and 0.12 µg/µL against bacteria associated with periodontal disease (Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum). Butanol and hexane fractions showed antiperiodontal activity with MBC of 0.12 and 1.0 µg/µL, respectively. In conclusion, Berberis goudotii total extract demonstrated antimicrobial activity against cariogenic and periodontal microorganisms, on the other hand, hexane and butanol fractions displayed antiperiodontal activity