Thymbra capitata essential oil has a significant antimicrobial activity against methicillin-resistant Staphylococcus aureus pre-formed biofilms.

Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant opportunistic pathogen with a great ability to form biofilms. Herein, the antimicrobial potential of Thymbra capitata essential oil (EO) against MRSA biofilms was investigated. The determination of the minimum inhibitory concentration (MIC) and the minimum lethal concentration (MLC) of the T. capitata EO was first investigated on a group of clinical isolates from septicaemias, diabetic foot ulcers and osteomyelitis. Biofilms were incubated with the EO at the MLC and its anti-biofilm potential was investigated. A strong antimicrobial activity was observed, with MIC and MLC values between 0·32 and 0·64 mg l-1 . However, the concentration of EO necessary for the eradication of planktonic cells was insufficient to significantly reduce the biofilm biomass of some isolates. Nevertheless, cell culturability and overall cellular metabolism was strongly reduced in all biofilms tested, only when the EO was tested. Contrary to the tested antibiotics, T. capitata EO showed a significant antimicrobial activity against MRSA biofilms, by reducing cellular metabolism and cellular culturability.

Antifungal activity of Ferulago capillaris essential oil against Candida, Cryptococcus, Aspergillus and dermatophyte species.

This study evaluates the composition, antifungal activity and mechanism of action of the essential oil of Ferulago capillaris (Link ex Spreng.) Cout. and its main components, limonene and α-pinene, against clinically relevant yeasts and moulds. Essential oil from the plant's aerial parts was obtained by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC-MS). Essential oil showed high contents of limonene (30.9%) and α-pinene (35.8%). Minimum inhibitory concentrations (MICs) were measured according to the reference Clinical and Laboratory Standards Institute (CLSI) broth macrodilution protocols. Cell suspensions were subcultured in solid medium and the minimum fungicidal concentrations (MFCs) were rendered. The effect of essential oil on germ tube formation, mitochondrial function and ergosterol biosynthesis was investigated. Essential oil and α-pinene displayed low and similar MIC and MFC values against tested organisms (0.08 to 5.0 µL/mL), while limonene showed a weaker activity (0.32 to 20 µL/mL). Essential oil inhibited germ tube formation at sub-inhibitory concentrations on Candida albicans. The exposure of C. albicans to the essential oil resulted in impairment of mitochondrial functions in a dose-dependent manner. No difference in ergosterol content was observed in essential oil-treated C. albicans. F. capillaris and α-pinene display a broad fungicidal activity. The fungicidal activity of F. capillaris on C. albicans can be related to an induced oxidative stress which affects enzymes activity and the membrane potential of mitochondria. The essential oil of F. capillaris was shown to have potential for use in the development of clinically useful therapeutic preparations, particularly for topical application in the management of superficial mycoses.

Antifungal activity of phenolic-rich Lavandula multifida L. essential oil.

This study evaluates the antifungal activity and mechanism of action of a new chemotype of Lavandula multifida from Portugal. The essential oil was analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS), and the minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) of the oil and its major compounds were determined against several pathogenic fungi responsible for candidosis, meningitis, dermatophytosis, and aspergillosis. The influence of the oil on the dimorphic transition in Candida albicans was also studied, as well as propidium iodide (PI) and FUN-1 staining of C. albicans cells by flow cytometry. The essential oil was characterized by high contents of monoterpenes, with carvacrol and cis-ß-ocimene being the main constituents. The oil was more effective against dermatophytes and Cryptococcus neoformans, with MIC and MLC values of 0.16 µL/mL and 0.32 µL/mL, respectively. The oil was further shown to completely inhibit filamentation in C. albicans at concentrations below the respective MIC (0.08 µL/mL), with cis-ß-ocimene being the main compound responsible for this inhibition (0.02 µL/mL). The flow cytometry results suggest a mechanism of action ultimately leading to cytoplasmic membrane disruption and cell death. L. multifida essential oil may be useful in complementary therapy to treat disseminated candidosis, since the inhibition of filamentation alone appears to be sufficient to treat this type of infection.

Monoterpenic aldehydes as potential anti-Leishmania agents: activity of Cymbopogon citratus and citral on L. infantum, L. tropica and L. major.

In order to contribute for the search of new drugs for leishmaniasis, we study the susceptibility of Leishmania infantum, Leishmania tropica and Leishmania major to Cymbopogon citratus essential oil and major compounds, mrycene and citral. C. citratus and citral were the most active inhibiting L. infantum, L. tropica and L. major growth at IC(50) concentrations ranging from 25 to 52 µg/ml and from 34 to 42 µg/ml, respectively. L. infantum promastigotes exposed to essential oil and citral underwent considerable ultrastructural alterations, namely mitochondrial and kinetoplast swelling, autophagosomal structures, disruption of nuclear membrane and nuclear chromatin condensation. C. citratus essential oil and citral promoted the leishmanicidal effect by triggering a programmed cell death. In fact, the leishmanicidal activity was mediated via apoptosis as evidenced by externalization of phosphatidylserine, loss of mitochondrial membrane potential, and cell-cycle arrest at the G(0)/G(1) phase. Taken together, ours findings lead us to propose that citral was responsible for anti-Leishmania activity of the C. citratus and both may represent a valuable source for therapeutic control of leishmaniasis.

Essential oil of Juniperus communis subsp. alpina (Suter) Celak needles: chemical composition, antifungal activity and cytotoxicity.

Essential oils are known to possess antimicrobial activity against a wide spectrum of bacteria and fungi. In the present work the composition and the antifungal activity of the oils of Juniperus communis subsp. alpina (Suter) Celak were evaluated. Moreover, the skin cytotoxicity, at concentrations showing significant antifungal activity, was also evaluated. The oils were isolated by hydrodistillation and analysed by gas chromatography and gas chromatography-mass spectrometry. Minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the oil against dermatophytes (Epidermophyton floccosum, Microsporum canis, M. gypseum, Trichophyton mentagrophytes, T. mentagrophytes var. interdigitale, T. rubrum, T. verrucosum), yeasts (Candida albicans, C. guillermondii, C. krusei, C. parapsilosis, C. tropicalis, Cryptococcus neoformans) and Aspergillus species (Aspergillus flavus, A. fumigatus, A. niger). Cytotoxicity was tested in HaCaT keratinocytes through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Essential oil of J. communis subsp. alpina needles was predominantly composed of monoterpene hydrocarbons (78.4%), with the main compounds being sabinene (26.2%), α-pinene (12-9%) and limonene (10.4%). Results concerning the antifungal activity demonstrated the potential of needle oil against dermatophytes, particularly for Microsporum canis and Trichophyton rubrum with MIC and MLC of 0.32 µL/mL. Furthermore, evaluation of cell viability showed no significant cytotoxicity in HaCaT keratinocytes at concentrations between 0.32 and 0.64 µL/mL. These results show that it is possible to find appropriate doses of J. communis subsp. alpina oil with both antifungal activity and a very low detrimental effect on keratinocytes.

Anti-Giardia activity of Syzygium aromaticum essential oil and eugenol: effects on growth, viability, adherence and ultrastructure.

The present work evaluates the anti-Giardia activity of Syzygium aromaticum and its major compound eugenol. The effects were evaluated on parasite growth, adherence, viability and ultrastructure. S. aromaticum essential oil (IC(50)=134 µg/ml) and eugenol (IC(50)=101 µg/ml) inhibited the growth of G. lamblia. The essential oil inhibited trophozoites adherence since the first hour of incubation and was able to kill almost 50% of the parasites population in a time dependent manner. The eugenol inhibited G. lamblia trophozoites adherence since the third hour and not induce cell lyses. The main morphological alterations were modifications on the cell shape, presence of precipitates in the cytoplasm, autophagic vesicles, internalization of flagella and ventral disc, membrane blebs, and intracellular and nuclear clearing. Taken together, our findings lead us to propose that eugenol was responsible for the anti-giardial activity of the S. aromaticum essential oil and both have potential for use as therapeutic agents against giardiasis.

Antifungal activity of essential oil from Mentha spicata L. and Mentha pulegium L. growing wild in Sardinia island (Italy).

This study aims to evaluate the antifungal activity of Mentha spicata L. and Mentha pulegium L. from Sardinia and to assess their efficacy on virulence factors for Candida albicans, particularly on the inhibition of the germ tube formation. The major compounds of the essential oils were carvone (62.9%) for M. spicata and pulegone (86.2%) for M. pulegium. The essential oil from M. spicata showed a more preeminent effect against Cryptococcus neoformans and the dermatophytes Trichophyton rubrum and T. verrucosum (0.32 µL/mL). Both oils were very effective in inhibiting C. albicans germ tube formation, at doses well below their MIC (0.16 µL/mL).

Unveiling the bioactive potential of the essential oil of a Portuguese endemism, Santolina impressa.

ETHNOPHARMACOLOGICAL RELEVANCE: Santolina species are widely used in traditional medicine in the Mediterranean region for their anti-inflammatory, antimicrobial, antispasmodic, digestive, and analgesic properties. S. impressa, a Portuguese endemism, is traditionally recognized for its beneficial anti-inflammatory properties in several gastrointestinal affections and is also used in oropharyngeal infections. AIM OF THE STUDY: The present study aims to characterize the essential oil of S. impressa growing in Portugal and validate its traditional uses by assessing the anti-inflammatory potential of its essential oil at concentrations without toxicity. The antifungal properties of the oil are also addressed, as well as, the putative mechanism of action underlying these effects. MATERIAL AND METHODS: The essential oil was obtained in accordance with the European Pharmacopoeia and characterized by GC and GC-MS. The anti-inflammatory potential of the oil was assessed on LPS-stimulated macrophages, through the production of nitric oxide (NO) using the Griess reaction. Putative mechanisms of action included the role of the oil as a NO scavenger, as well as its effect on the expression of two key pro-inflammatory enzymes, iNOS and COX-2 by Western blot analysis. The antifungal effect of the oil was evaluated according to the CLSI guidelines on several yeast and filamentous strains and on two major virulence factors in Candida albicans, namely germ tubes and biofilms. Ultrastructural modifications on dermatophytes were also unveiled by transmission electron microscopy. RESULTS: S. impressa essential oil was primarily characterized by the presence of monoterpene hydrocarbons and oxygenated monoterpenes, being the main compounds ß-pinene (22.5%), 1,8-cineole (10.0%), limonene (9.1%), camphor (8.1%) and ß-phellandrene (8.0%). A significant decrease (ca 60.0%) in nitrite levels was observed in LPS-stimulated macrophages treated with the oil without affecting cell viability. This effect could be explained by a great reduction on iNOS expression (85.0% inhibition), thus underpinning the anti-inflammatory potential of the oil. The oil also showed a fungicidal effect, being more active against Cryptococcus neoformans, Epidermophyton floccosum and Trichophytum rubrum. For these dermatophytes, significant ultrastructural modifications in cell wall structure were detected. Strikingly, for C. albicans, the oil showed a significant anti-infective potential (at 0.07 mg/mL for germ tube inhibition and 0.02 mg/mL for biofilm disruption) before fungal growth inhibition occurred. CONCLUSIONS: Our results validate the main traditional use ascribed to S. impressa, namely its anti-inflammatory effect. In addition, an antifungal potential is pointed out, thus corroborating the antimicrobial uses and adding new value to an endemic species poorly recognized by the industry.

Meat quality in relation to swine well-being after transport and during lairage at the slaughterhouse.

Cortisol and corticosterone in saliva were evaluated as pig stress biomarkers, using pig genotype (Duroc, L62 or Pietrain) and lairage time in the slaughterhouse (0, 2.0, 4.0 or 6.0 h) as controlled variables. Although some pigs were found to be carriers of stress susceptibility, all were healthy heterozygous individuals. Pre-slaughter transport increased cortisol levels in saliva above 3.0 µg/L (medium stress), and 4.0 h of lairage in the slaughterhouse raised them above 6.0 µg/L, whereas corticosterone concentrations exceeded 4 µg/L, which are suggestive of high stress. The highest cortisol levels were detected in the Duroc genotype. Other factors such as food deprivation, background noise, the presence of a large number of animals waiting to be slaughtered, mixing with unfamiliar animals or recent mixing of genders may also influence stress. Corticosterone proved a reliable indicator of high stress only. Meat quality from the pig breeds studied was not affected by lairage in the slaughterhouse for up to 6.0 h.

Composition and antifungal activity of the essential oil of Mentha cervina from Portugal.

The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of Mentha cervina collected during the flowering and vegetative phases of the plants were investigated by GC and GC-MS. Quantitative differences were observed in the compositions, particularly in the amounts of pulegone (12.9-79.6%) and isomenthone (8.7-77.0%). Antifungal activity of the oils was evaluated by minimal inhibitory concentrations (MIC) and minimal lethal concentrations (MLC) against Candida, Apergillus and dermatophyte strains. Antifungal activity of the sample containing lower amounts of pulegone was the highest for dermatophytes, particularly for Epidermophyton floccosum with MIC and MLC values of 0.63 microL mL( - 1). Mentha cervina oils with low content of pulegone, may be an alternative as antifungal agents in dermatophytosis.

Isolation of Crithmum maritimum L. volatile oil by supercritical carbon dioxide extraction and biological assays.

The chemical composition of the volatile concentrate obtained by supercritical CO2 extraction of aerial parts of Crithmum maritimum L. growing spontaneously in one area of Mediterranean coast (Buggerru, Sardinia Island, Italy) and in two areas of the Atlantic coast (Figueira da Foz and S. Pedro de Moel, Portugal) was investigated by GC and GC-MS. The major oil components identified were p-cymene, beta-phellandrene, gamma-terpinene, thymol methyl ether and dillapiole. The results showed the presence of two chemotypes of C. maritimum with different dillapiole contents, ranging from 0.2 to 64.2% in Portuguese and Italian plants, respectively. The minimal inhibitory concentration (MIC) and the minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the oils against yeasts and dermatophyte strains. All the oils exhibited significant antifungal activity against dermatophyte strains. The oil with the higher amount of dillapiole (64.2%) was the most active with MIC values ranging from 0.08-0.32 microL mL(-1).

Assessment of safe bioactive doses of Foeniculum vulgare Mill. essential oil from Portugal.

This study was designed to evaluate the antifungal activity of Foeniculum vulgare essential oil; concomitantly, the safety of bioactive doses was also unveiled, for the first time, in several mammalian cells. The chemical characterisation was made by GC and GC-MS. Antifungal activity was evaluated against yeasts, dermatophytes and Aspergillus strains and germ tube inhibition assay was evaluated using Candida albicans. Cell viability was assessed by the MTT assay. The main constituents of the oil are E-anetol (47%), α-phellandrene (11%), α-pinene (10.1%) and fenchone (10.8%). The oil was more active against Cryptococcus neoformans and C. albicans (MICs 0.32-0.64 µL/mL) and the filamentation of C. albicans was totally inhibited with 0.08 µL/mL. The oil is safe for keratinocytes, hepatocytes and fibroblasts in concentrations up to 1.25 µL/mL, and to macrophages up to 0.64 µL/mL. These findings highlight safe bioactive concentrations that should be deeper investigated for further application in pharmaceutical industry.

Do low-risk nulliparous women with abnormal uterine artery Doppler in the third trimester have poorer perinatal outcomes? A longitudinal prospective study on uterine artery Doppler in low-risk nulliparous women and correlation with pregnancy outcomes.

OBJECTIVE: To evaluate uterine artery (UtA) Doppler over the course of pregnancy in low-risk nulliparous women and to analyze whether an abnormal uterine artery pulsatility index (UtA-PI) at a 32-34 week' scan implies poorer perinatal outcomes. METHODS: An observational prospective study was carried out including 616 low-risk nulliparous women. Women with any of the following were excluded: fetal abnormalities, multiple pregnancy, and heparin, metformin or hypotensive treatment. Maternal characteristics, mean arterial pressure measurements and UtA Doppler findings were recorded longitudinally. RESULTS: Complete pregnancy data were available for 489/616 women (79.3%). Of these, 385 women had a normal UtA-PI throughout pregnancy (Group 0), while 50 (10.1%) had an UtA-PI > 95th percentile in the first or the second trimester that normalized in the third trimester (Group 1), and 56 (11.4%) had an abnormal UtA-PI in the third trimester (Group 2). We found that the rate of pre-eclampsia (PE) was higher in Group 2 (7/56 versus 4/435, p = 0.003) as was the rate of intrauterine growth restriction (IUGR) (6/56 versus 14/435, p = 0.02). CONCLUSIONS: Low-risk nulliparous women with abnormal UtA Doppler findings in the third trimester are at a higher risk of developing PE and having a baby with IUGR.

Chemical composition and biological activities of Artemisia judaica essential oil from southern desert of Jordan.

ETHNOPHARMACOLOGIC RELEVANCE: Artemisia judaica L. (Arabic name: Beithran), is a medicinal and aromatic plant growing in the valley bottoms of desert areas, particularly in the southern desert of Jordan nearest to the Jordan-Saudi Arabia borders and in Wadi Araba in the Southern Badia. In Jordan, A. judaica is widely used in traditional medicine being recommended by aboriginal Bedouins in the North Badia region of Jordan as calmative. Furthermore, it is used for the treatment of stomach ache, heart diseases, sexual weakness, diabetes, gastro-intestinal disorders and external wounding. Additionally, other folk medicines of the Arabic region commonly use this aromatic plant for the treatment of inflammatory-related diseases, for instance fungal infections, diabetes, atherosclerosis, cancer and arthritis. AIM OF THE STUDY: Considering the traditional medicinal uses and the lack of scientific studies addressing the cellular and molecular mechanisms behind A. judaica claimed activities, the present study was designed to validate some of the traditional uses ascribed to this species, specifically the antifungal and anti-inflammatory activities of A. judaica essential oil at doses devoid of cytotoxicity to mammalian cells. MATERIALS AND METHODS: Chemical analysis of A. judaica essential oil isolated by hydrodistillation from aerial parts was carried out by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antifungal activity (minimal inhibitory concentrations and minimal lethal concentrations) was evaluated against yeasts, dermatophyte and Aspergillus strains. In order to deeply explore the mechanisms behind the anti-fungal effect of the essential oil, the germ tube inhibition assay and the biofilms formation assay were evaluated using Candida albicans. The assessment of cell viability was accomplished using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in both hepatocytes and macrophages. Furthermore, the in vitro anti-inflammatory potential of A. judaica oil was evaluated by measuring nitric oxide (NO) production using lipopolysaccharide (LPS)-stimulated mouse macrophages. RESULTS: Oxygen containing monoterpenes are a representative group of constituents (68.7%) with piperitone (30.4%), camphor (16.1%) and ethyl cinnamate (11.0%) as main compounds. The highest antifungal activity of the oil was observed against Cryptococcus neoformans, with a MIC value of 0.16µL/mL. The oil revealed an important inhibitory effect on germ tube formation in C. albicans with 80% inhibition of filamentation at a concentration of 0.16µL/mL. Importantly, the oil also interfered with pre-formed biofilms by reducing the amount of the attached biomass. Furthermore, the essential oil significantly inhibited NO production evoked by LPS on macrophages at concentrations with very low toxicity (0.32µL/mL) or without toxicity (0.16µL/mL) to both macrophages and hepatocytes. CONCLUSIONS: The present study revealed that A. judaica essential oil from Jordan significantly inhibited germ tube formation and disrupted preformed biofilms of C. albicans, emphasizing the therapeutic potential for the treatment of disseminated candidiasis. Additionally, safe concentrations of this essential oil significantly inhibited NO production elicited by LPS in macrophages, highlighting its potential anti-inflammatory activity. Overall, A. judaica bears promising therapeutic potential for further drug development. Importantly, this work also validates some of the traditional uses of A. judaica.

Ziziphora tenuior L. essential oil from Dana Biosphere Reserve (Southern Jordan); Chemical characterization and assessment of biological activities.

ETHNOPHARMACOLOGIC RELEVANCE: Ziziphora tenuior L. (Lamiaceae) is a medicinal plant in Jordan, which is included in various antimicrobial, antiseptic, expectorant and wound healing preparations. It is used for the treatment of cough, stomach ache, dysentery, fever, uterus infection, gut inflammation and painful menstruation. AIM OF THE STUDY: The aim of this study was to assess, for the first time, the chemical composition of the essential oil of Z. tenuior originated from southern Jordan and its antifungal effects against several yeasts. Concomitantly, the mechanisms behind the anti-fungal activity against Candida albicans were also disclosed. Since the Z. tenuior traditional uses are related with inflammatory-associated conditions, the putative anti-inflammatory activity of the oil was also unveiled. Importantly, the potential toxicity of pharmacologically active concentrations was screened in different types of mammalian cells. MATERIALS AND METHODS: Z. tenuior essential oil, isolated by hydrodistillation, was analyzed by gas chromatography, gas chromatography-mass spectrometry and 13C nuclear magnetic resonance spectroscopy. Antifungal activity was evaluated against yeasts, dermatophytes and Aspergillus strains. Germ tube inhibition and biofilm formation assays were evaluated using C. albicans. Assessment of cell viability was made by the MTT assay using different types of mammalian cells, including hepatocytes, keratinocytes and macrophages. The in vitro anti-inflammatory potential of the oil was evaluated by measuring nitric oxide production using lipopolysaccharide-stimulated mouse macrophages. RESULTS: Oxygen-containing monoterpenes are the main oil compounds: pulegone (46.8%), p-menth-3-en-8-ol (12.5%), isomenthone (6.6%) and 8-hydroxymenthone (6.2%). The highest antifungal activity was against Cryptococcus neoformans, with a MIC value of 0.16µL/mL. The oil revealed an important inhibitory effect on germ tube formation with a filamentation inhibition rate higher than 80% at 0.16µL/mL. The amount of the attached biomass was reduced. Importantly, concentrations devoid of toxicity on several mammalian cell types still displayed anti-inflammatory activity (0.16 and 0.32µL/mL). CONCLUSIONS: These findings add significant information to the pharmacological activity of Z. tenuior, thus justifying and reinforcing the use of this plant in traditional medicine. Additionally, the antifungal and anti-inflammatory potential of the oil at non-toxic concentrations, opens new avenues for its further exploitation, for instance in health-care product development.

Chemical composition and antibacterial activity of Lavandula coronopifolia essential oil against antibiotic-resistant bacteria.

The aim of this study was to analyse the composition of the essential oil (EO) of Lavandula coronopifolia from Morocco and to evaluate its in vitro antibacterial activity against antibiotic-resistant bacteria isolated from clinical infections. The antimicrobial activity was assessed by a broth micro-well dilution method using multiresistant clinical isolates of 11 pathogenic bacteria: Klebsiella pneumoniae subsp. pneumoniae, Klebsiella ornithinolytica, Escherichia coli, Enterobacter cloacae, Enterobacter aerogenes, Providencia rettgeri, Citrobacter freundii, Hafnia alvei, Salmonella spp., Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus. The main compounds of the oil were carvacrol (48.9%), E-caryophyllene (10.8%) and caryophyllene oxide (7.7%). The oil showed activity against all tested strains with minimal inhibitory concentration (MIC) values ranging between 1% and 4%. For most of the strains, the MIC value was equivalent to the minimal bactericidal concentration value, indicating a clear bactericidal effect of L. coronopifolia EO.

Artemisia herba-alba essential oil from Buseirah (South Jordan): Chemical characterization and assessment of safe antifungal and anti-inflammatory doses.

ETHNOPHARMACOLOGIC RELEVANCE: Artemisia herba-alba Asso ("desert wormwood" in English; "armoise blanche" in French; "shaih" in Arabic), is a medicinal and strongly aromatic plant widely used in traditional medicine by many cultures since ancient times. It is used to treat inflammatory disorders (colds, coughing, bronchitis, diarrhea), infectious diseases (skin diseases, scabies, syphilis) and others (diabetes, neuralgias). In Jordanian traditional medicine, this plant is used as antiseptic and against skin diseases, scabies, syphilis, fever as well as menstrual and nervous disorders. AIM OF THE STUDY: Considering the traditional medicinal uses and the lack of scientific studies addressing the cellular and molecular players involved in these biological activities, the present study was designed to unveil the antifungal and anti-inflammatory activities of A. herba-alba Asso essential oil at doses devoid of toxicity to mammalian cells. MATERIALS AND METHODS: Chemical analysis of A. herba-alba essential oil isolated by hydrodistillation from aerial parts was carried out by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antifungal activity (minimal inhibitory concentrations and minimal lethal concentrations) was evaluated against yeasts, dermatophyte and Aspergillus strains. In order to explore the mechanisms behind the anti-fungal effect of the essential oil, the germ tube inhibition assay was evaluated using Candida albicans. The assessment of cell viability was accomplished using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the in vitro anti-inflammatory potential of A. herba-alba oil at the periphery and central nervous system was evaluated by measuring nitric oxide (NO) production using lipopolysaccharide (LPS)-stimulated mouse macrophages and microglia, respectively. RESULTS: Oxygen-containing monoterpenes are the main compounds of the oil, namely 1,8-cineole (20.1%), ß-thujone (25.1%), α-thujone (22.9%) and camphor (10.5%). Among the fungal strains tested, the oil demonstrated potential against Trichophyton rubrum and Epidermophyton floccosum, with minimal inhibitory concentration (MIC) and minimal lethal concentration (MCL) values of 0.32 mg/mL and Cryptococcus neoformans with MIC of 0.64 mg/mL. The oil revealed a strong inhibitory effect on germ tube formation in C. albicans with inhibition of filamentation around 90% at a concentration 0.16 mg/mL. Importantly, the essential oil significantly inhibited NO production evoked by LPS without cytotoxicity at concentrations up to 1.25 µL/mL in macrophages and up to 0.32 µL/mL in microglia. Furthermore, evaluation of cell viability in RAW 264.7 macrophages, BW2 microgliacells and HaCaT keratinocytes showed no cytotoxicity at concentrations up to 0.32 µL/mL. CONCLUSIONS: It was possible to find appropriate doses of A. herba-alba oil with both antifungal and anti-inflammatory activities and without detrimental effects towards several mammalian cell types. These findings add significant information to the pharmacological activity of A. herba-alba essential oil, specifically to its antifungal and anti-inflammatory therapeutic value, thus justifying and reinforcing the use of this plant in traditional medicine.

Diet and gastric cancer in Portugal--a multivariate model.

Diet and gastric cancer mortality in Portugal was studied using a multivariate ecological model. The factors investigated over 18 districts were the relationship between gastric cancer mortality (1994-96), dietary habits, and socio-economic factors (1980-81). Mortality geographical pattern was established using age-standardized mortality rates, per capita dietary consumption of foodstuffs and nutrients was obtained from the National Alimentary Survey (1980-81), and data on socio-economic factors from the 1981 National Census. Pearson correlation coefficients and simple and multiple linear regression models were used. The mortality geographical pattern resembled a north-south gradient, and dietary habits and socio-economic factors had great variability throughout the country. The highest negative correlation coefficients between dietary consumption and gastric cancer mortality were obtained for vegetables, fruit, vitamin A and carotene consumption, and the highest positive coefficients were for rice, wine and carbohydrate consumption. No significant correlations were obtained for socio-economic factors. In multiple regression analysis, vegetable and rice consumption could account for 79% of the gastric cancer mortality variability for males, and vegetable and meat consumption could account for 69% of this variability for females. Interestingly, meat consumption was found to be protective. A mean increase of 100 g/person/day in vegetable consumption would imply a mean predicted decrease of 10 (95% CI 6-14) and 5 (95% CI 3-7) gastric cancer deaths per 100,000 persons/year, for males and females respectively, in simple regression analysis. Such a decrease represents about one-third of the mean national gastric cancer mortality rate. Therefore, an increase in vegetable consumption is strongly recommended.

Chemical polymorphism of the essential oils from populations of Thymus caespititius grown on the island S. Jorge (Azores).

The compositions of the essential oils obtained from ten populations of Thymus caespititius grown on S. Jorge (Azores) were studied by GC and GC-MS. All the oils analysed were dominated by their monoterpene fraction (69-9%). The sesquiterpene fraction was rather small (4-17%) and consisted mainly of oxygen-containing compounds (3-13%). Enantiomeric ratio of sabinene and alpha-terpineol was investigated in the oils from some populations. (+)-Sabinene was detected with high enatiomeric purity (96 99%). Although ( +)-alpha terpineol was the predominant enantiomer, its purity varied considerably (66-97%). Cluster analysis of all identified components grouped the oils into four main clusters that corresponded with their major components: alpha-terpineol (43-68%), carvacrol (32-52%), thymol (44-58%) and sabinene (41%). The essential oil from Th. caespititius showed a clear chemical polymorphism, that was particularly evident among four populations growing along a 200 m distance at Pico Verde.

Analysis by gas chromatography-mass spectrometry of the volatile components of Teucrium lusitanicum and Teucrium algarbiensis.

The essential oils from four samples of Teucrium lusitanicum and one sample of Teucrium algarbiensis, grown in Algarve (southern Portugal) were analyzed by gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). Seventy-one volatile compounds were identified. Major compounds of T. algarbiensis oil were alpha-pinene (8.3%), sabinene (7.2%), beta-pinene (10.2%), limonene (11.8%) and germacrene D (7.6%). Concerning T. lusitanicum, some quantitative differences were found with regards to the major constituents of the oils from four populations: alpha-pinene (0.8-8.5%), sabinene (2.1-9.6%), beta-pinene (2.5-11.9%), limonene (1.2-11.5%) and elemol (2.6-12.0%).