Evaluation of Marrubium vulgare Growing Wild in Tunisia for Its Potential as a Dietary Supplement.

Marrubium vulgare L., known as horehound, is a widespread and widely known plant that is used in beer breweries and also as a traditional remedy in Tunisia. In this study, methanolic extracts of plants harvested from five different locations were investigated for their antioxidant activities using three assays (ferric reducing power, radical scavenging activity, and ß-carotene-linoleic acid bleaching assay) as well as the total phenolic content. The mineral composition of the plant was also investigated concerning the following elements: Fe, Mg, Ca, Cu, Zn, Mn, K, and three heavy metals, Ni, Pb, and Cd. Marrubiin, the major bioactive diterpenoid lactone, was quantified by NMR in the samples. The essential oils were obtained by hydrodistillation, and their radical scavenging activity was investigated. The toxicity of essential oils was evaluated against Artemia salina (the brine shrimp larva). The essential oil showed a weak radical scavenging activity and low toxicity. Data obtained from the five different locations showed that the antioxidant activity, as well as the total phenolic and marrubiin content, were strongly affected by the harvest sites. The metal content in the samples showed differences with the harvest location, but there was always a great abundance of calcium, magnesium, and potassium.

Seasonal Variations of the Nutritive Value and Phytotherapeutic Potential of Cladium mariscus L. (Pohl.) Targeting Ruminant's Production.

In our endeavor to identify salt-tolerant plants with potential veterinary uses in ruminants' production strategies, we focused on Cladium mariscus L. Pohl (sawgrass), due to its high total phenolic and tannin content, anti-radical properties, and ethnomedicinal uses. Aerial parts were collected along the year in Southern Portugal and evaluated for the nutritional profile and in vitro organic matter digestibility (IVOMD), aiming for its use as feed. Acetone extracts were appraised for total contents in phenolics (TPC), flavonoids (TFC), and tannins (CTC), as well as the chemical composition by HPLC-DAD and in vitro antioxidant and anti-inflammatory properties, targeting its exploitation as phytotherapeutic products. Sawgrass biomass has a limited nutritive value, due to its high neutral detergent fiber (NDF; 596-690 g kg-1 dry matter (DM)) and acid detergent fiber (ADF; 330-418 g kg-1 DM) contents, low crude protein (51.8-87.3 g kg-1 DM) and IVOMD (172-317 g kg-1 organic matter (OM)). Despite differences among seasons, the mineral profile was adequate. The extracts were rich in TPC (88-112 mg g-1), CTC (115-169 mg g-1), and TFC (18.5-20.2 mg g-1), and displayed significant antioxidant capacity, particularly in summer and autumn, whilst no seasonal influence was detected for anti-inflammatory properties (30% reduction of nitric oxide production). Eleven phenolics were quantified: chlorogenic, ferulic, and syringic acids were the most abundant, especially in the autumn sample. Overall, despite the low nutritional interest, sawgrass extracts hold the potential as a source of antioxidant and anti-inflammatory phenolic compounds.

Photocatalytic degradation of acetaminophen and caffeine using magnetite-hematite combined nanoparticles: kinetics and mechanisms.

The increased use of pharmaceutical and personal care products (PPCPs) has contributed to the contamination of water systems and put pressure on the development of new techniques to deal with this problem. Acetaminophen (paracetamol), a common analgesic and antipyretic drug, and caffeine, a known central nervous system stimulant, are being used frequently by many people and found in large amounts in wastewater systems. In this work, their removal, by photocatalytic degradation, was promoted using magnetic nanoparticles (NPs) based on iron oxides. Besides being obtained from cheap and plentiful source, the magnetic properties of these NPs provide an easy way to separate them from the solution when the reaction is complete. Three types of hematite-based NPs, one pure (1) and two of them composed by a magnetite core partially (2) or completely (3) covered by a hematite shell, were synthesized and characterized. Sample 2 was the best photocatalyst for both pollutants' photo-assisted degradation. Under UV-vis irradiation and using a 0.13 g catalyst/L solution, the total acetaminophen and caffeine degradation (20 ppm/150 mL) was achieved in 45 min and 60 min, respectively. The identification of some of the intermediate products was carried out by liquid chromatography in combination with electrospray ionization mass spectrometry. A complementary Density Functional Theory (DFT) study revealed the relative stability of several species formed during the acetaminophen and caffeine degradation processes and gave some insight about the most favorable degradation pathways.

In vitro enzyme inhibitory and anti-oxidant properties, cytotoxicity and chemical composition of the halophyte Malcolmia littorea (L.) R.Br. (Brassicaceae).

This work reports for the first time the in vitro anti-oxidant (towards DPPH, ABTS, copper and iron), enzymatic inhibitory (on AChE, BuChE, α-glucosidase, α-amylase and tyrosinase), cytotoxicity (towards HepG2 and HEK 293 cells), and metabolomics (by HPLC-MS) of extracts from organs of Malcolmia littorea (L.) R.Br. Extracts were constituted mainly by phenolic acids and flavonoids, and main compounds were salicylic acid and luteolin-7-O-glucoside. Samples showed reduced radical scavenging and metal chelating capacity, and only the methanol extracts reduced iron. The root's ethanol and methanol extracts, and the aerial organ's ethanol extract exhibited the highest AChE inhibition. The root's ethanol extract displayed dual anti-cholinesterase activity. Samples showed a low capacity to inhibit α-amylase, but a high α-glucosidase inhibition was obtained with the root's and flower's ethanol extracts, and flower's methanol extract. Overall, samples displayed a high inhibition against tyrosinase, reduced HepG2 cellular viability and were less toxic towards HEK 293 cells.

An Overview on the Properties of Ximenia Oil Used as Cosmetic in Angola.

Ximenia (Ximeniaamericana L.) is a shrub, or small tree, native from Africa and spread across different continents. In Angola, the seeds oil is used by local populations, to prevent sunburn, to smooth and hydrate the skin, and to give it a pleasant color and elasticity, to prevent stretch marks, in pregnant woman, and also as hair conditioner. Herein, an oil sold in the region (LPO), and two others extracted in laboratory, from seeds collected in the same region, were investigated in terms of their composition, chemical properties, UV transmission. The three oils are similar although the LPO is more acidic, 0.48 mg KOH/g. GC-MS analysis indicated that the major components are the fatty acids, oleic (31.82%), nervonic (11.09%), ximenic (10.22%), and hexacosa-17,20,23-trienoic acids (14.59%). Long chain fatty acids, n ≥ 20, accounted for 51.1% of the total fatty acids. A thin film of the oil showed a reduction in transmittance from 200 to 300 nm. Viscosity studies of the LPO indicated that at normal temperature of skin, the oil can be spread over the skin as a thin film. At concentrations up to 10 µg/mL, the LPO is not toxic to human keratinocytes, suggesting the safety of this oil.

Antibiofilm activity of the essential oil of citronella (Cymbopogon nardus) and its major component, geraniol, on the bacterial biofilms of Staphylococcus aureus.

Medicinal plants with antimicrobial action have been investigated for uses against biofilms, among which, Cymbopogon nardus, citronella, stands out as a promising species. The present study aims to evaluate the antimicrobial and antibiofilm action of the essential oil of C. nardus (EOCN) and geraniol on Gram-negative and positive bacteria from the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration and inhibition of biofilms. In the results, the EOCN produced a 41 mm halo on S. aureus, which was susceptible with MIC values of 0.5 and 0.25 mg/mL for the EOCN and geraniol respectively, both with bactericidal effect. The antibiofilm action was confirmed, the EOCN and geraniol reduced the biofilm biomass of S. aureus up to 100% between 0.5 and 4 mg/mL concentrations. The reduction of cell viability was 0.25 and 1 mg/mL, of EOCN and geraniol, respectively. EOCN and geraniol were shown to be promising antibiotic against S. aureus.

First report of the in vitro antileishmanial properties of extremophile plants from the Algarve Coast.

This work reports for the first time the in vitro anti Leishmania infantum activity of acetone and dichloromethane (DCM) extracts from 25 extremophile plants from Southern Portugal. DCM extracts from Inula chritmoides and Spergularia rubra were active against axenic promastigotes and intracellular amastigotes, had anti-inflammatory properties on lipopolysaccharide (LPS)-stimulated macrophages, inhibited acetylcholinesterase and had no haemolytic activity on human erythrocytes. Eleven phenolics were identified by high-performance liquid chromatography with diode-array detection (HPLC-DAD) in I. crithmoides and one phenolic in S. rubra. Isolation and identification of the active molecules is in progress.

Novel in vitro and in silico insights of the multi-biological activities and chemical composition of Bidens tripartita L.

Bidens tripartita L. is a traditional phyto-remedy used in several countries, yet there is still a paucity of data on its biological potential. We aimed to provide new insights on the pharmacological potential of extracts prepared from B. tripartita via highlighting its antioxidant, key enzymes inhibitory potency, and DNA protecting effects. Phytochemical profile was established using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) and bioactive compound(s) docked against target enzymes using in silico methods. Cytotoxicity against three cancer cell lines was assessed using the methylthiazolyldiphenyl-tetrazolium bromide (MTT) cell viability test. The main compounds were luteolin-7-glucoside (cynaroside), chlorogenic acid, and epicatechin in the extracts. The methanol extract exhibited the highest radical scavenging activity. Ethyl acetate extract showed strongest α-amylase inhibitory activity, while the best α-glucosidase inhibitory effect recorded for the methanol extract. Molecular docking showed that cynaroside strongly interact to α-glucosidase cavity by establishing six hydrogen bonds. B. tripartita extracts were found to protect supercoiled form of pUC19 plasmid (>70%) and also showed anti-proliferative properties. Results amassed in the present study add on to a growing body of literature on the multi-pharmacological potency of B. tripartita which can be applied to bio-products development geared towards management of common diseases.

Searching for new sources of innovative products for the food industry within halophyte aromatic plants: In vitro antioxidant activity and phenolic and mineral contents of infusions and decoctions of Crithmum maritimum L.

Aromatic halophyte plants are an outstanding source of bioactive compounds and natural products with potential use in the food industry. This work reports the in vitro antioxidant activity, toxicity, polyphenolic profile and mineral contents of infusions and decoctions from stems, leaves and flowers of Crithmum maritimum L., an aromatic and edible maritime halophyte (sea fennel). Aspalathus linearis (Burm.f.) Dahlg. (rooibos) herbal tea was used as a reference. Sea fennel's tisanes, particularly from leaves, were rich in phenolic compounds and five of them (p-hydroxybenzoic and ferulic acids, epicatechin, pyrocatechol and 4-hydroxybenzaldehyde) were here described in C. maritimum for the first time. Chlorogenic acid was the dominant phenolic determined. Na was the most abundant mineral in all tisanes followed by Ca and Mg in leaves' tisanes and K in flowers. Sea fennel's samples had a similar antioxidant activity than those from A. linearis, and had no significant toxicity towards four different mammalian cell lines. Altogether, our results suggest that sea fennel can be a source of products and/or molecules for the food industry with antioxidant properties and minerals in the form, for example, of innovative health-promoting herbal beverages.

Unlocking the in vitro anti-inflammatory and antidiabetic potential of Polygonum maritimum.

CONTEXT: Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes. OBJECTIVE: Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L. MATERIAL AND METHODS: Antioxidant activity was determined (up to 1 mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24 h at concentrations up to 100 µg/mL and antidiabetic potential was assessed by α-amylase and α-glucosidase inhibition (up to 10 mg/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS). RESULTS: The methanol leaf extract had the highest activity against DPPH• (IC50 = 26 µg/mL) and ABTS+• (IC50 = 140 µg/mL), FRAP (IC50 = 48 µg/mL) and CCA (IC50 = 770 µg/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC50 = 48 µg/mL). The methanol root (IC50 = 19 µg/mL) and leaf (IC50 = 29 µg/mL) extracts strongly inhibited baker's yeast α-glucosidase, but LDCM had higher rat's α-glucosidase inhibition (IC50 = 2527 µg/mL) than acarbose (IC50 = 4638 µg/mL). GC-MS analysis identified ß-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities. CONCLUSIONS: Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.

Euphorbia denticulata Lam.: A promising source of phyto-pharmaceuticals for the development of novel functional formulations.

In this study, Methanolic extracts of Euphorbia denticulata parts (flowers, leaf, stem, and mix of aerial parts) were assessed for a panoply of bioactivities. Inhibitory potential against key enzymes involved in diabetes (α-glucosidase and α-amylase), obesity (pancreatic lipase), neurodegenerative diseases (cholinesterases), and hyperpigmentation (tyrosinase) was evaluated. The antioxidant and antibacterial properties were also assessed. The total phenolic, flavonoid, and phytochemical profile were established using HPLC/DAD and molecular modelling studies on specific target compounds were performed in silico. The flower extract was found to be rich in phenolics and flavonoids, (60.11±1.40mgGAE/g and 42.04±0.16mgRE/g respectively), which tend to correlate with the high radical scavenging activity of this extract (120.34±3.33mgTE/g and 165.42±2.16mgTE/g for DPPH and ABTS respectively). Catechin, epicatechin, gallic acid, p-OH-Benzoic acid, rosmarinic acid, and epigallocatechin gallate, found in significant abundance in the extracts were assessed using molecular modelling with the aim to study their docking properties on a set of six enzymes used in this study. The extracts were moderately effective with MIC values ranging between 1.56 to 6.25mg/ml, but potent growth inhibitors of MRSA strains. Results amassed herein can be used as a stimulus for further studies geared towards the development of novel phyto-pharmaceuticals.

Isololiolide, a carotenoid metabolite isolated from the brown alga Cystoseira tamariscifolia, is cytotoxic and able to induce apoptosis in hepatocarcinoma cells through caspase-3 activation, decreased Bcl-2 levels, increased p53 expression and PARP cleavage.

BACKGROUND: Brown macroalgae have attracted attention because they display a wide range of biological activities, including antitumoral properties. Inthis study we isolated isololiolide from Cystoseira tamariscifolia for the first time. PURPOSE: To examine the therapeutical potential of isololiolide against tumor cell lines. METHODS/STUDY DESIGN: The structure of the compound was established and confirmed by 1D and 2D NMR as well as HRMS spectral analysis. The in vitro cytotoxicity was analyzed by colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in tumoral as well as in non-tumoral cell lines. Cell cycle arrest and induction of apoptosis were assessed by flow cytometry. Alteration of expression levels in proteins important in the apoptotic cascade was analyzed by western blotting. RESULTS: Isololiolidewas isolated for the first time from the brown macroalga C.tamariscifolia. Isololiolide exhibited significant cytotoxic activity against three human tumoral cell lines, namely hepatocarcinoma HepG2 cells, whereas no cytotoxicity was found in non-malignant MRC-5 and HFF-1 human fibroblasts. Isololiolide completely disrupted the HepG2 normal cell cycle and induced significant apoptosis. Moreover, western blot analysis showed that isololiolide altered the expression of proteins that are important in the apoptotic cascade, increasing PARP cleavage and p53 expression while decreasing procaspase-3 and Bcl-2 levels. CONCLUSION: Isololiolide isolated from C. tamariscifolia is able to exert a selective cytotoxic activity on hepatocarcinoma HepG2 cells as well as induce apoptosis through the modulation of apoptosis-related proteins.

In vitro antioxidant and anti-inflammatory properties of Limonium algarvense flowers' infusions and decoctions: A comparison with green tea (Camellia sinensis).

This work reports the in vitro antioxidant and anti-inflammatory activities and toxicity of infusions and decoctions of Limonium algarvense flowers, and green tea. The total contents in different phenolic groups and the quantification of individual phenolics by HPLC are also reported. L. algarvense and green tea had similar antioxidant properties, except for hydroxyl radical-scavenging activity, higher on green tea, and iron chelating potential, higher on L. algarvense. The later species also had the uppermost anti-inflammatory potential. Green tea decoction had the highest content of phenolic groups, but the infusion of L. algarvense had higher amounts of salicylic, gallic and coumaric acids. L. algarvense was not toxic, whereas green tea was toxic for S17 cells. Under our experimental conditions, infusions and decoctions of L. algarvense flowers had similar or higher antioxidant and anti-inflammatory properties than green tea, and thus, may be useful for alleviating symptoms associated with oxidative and inflammatory-related diseases.

Ocular Inserts for Sustained Release of the Angiotensin-Converting Enzyme 2 Activator, Diminazene Aceturate, to Treat Glaucoma in Rats.

The aim of this study was to develop and evaluate the effects of chitosan inserts for sustained release of the angiotensin-converting enzyme 2 (ACE2) activator, diminazene aceturate (DIZE), in experimental glaucoma. Monolayer DIZE loaded inserts (D+I) were prepared and characterized through swelling, attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and in vitro drug release. Functionally, the effects of D+I were tested in glaucomatous rats. Glaucoma was induced by weekly injections of hyaluronic acid (HA) into the anterior chamber and intraocular pressure (IOP) measurements were performed. Retinal ganglion cells (RGC) and optic nerve head cupping were evaluated in histological sections. Biodistribution of the drug was accessed by scintigraphic images and ex vivo radiation counting. We found that DIZE increased the swelling index of the inserts. Also, it was molecularly dispersed and interspersed in the polymeric matrix as a freebase. DIZE did not lose its chemical integrity and activity when loaded in the inserts. The functional evaluation demonstrated that D+I decreased the IOP and maintained the IOP lowered for up to one month (last week: 11.0 ± 0.7 mmHg). This effect of D+I prevented the loss of RGC and degeneration of the optic nerve. No toxic effects in the eyes related to application of the inserts were observed. Moreover, biodistribution studies showed that D+I prolonged the retention of DIZE in the corneal site. We concluded that D+I provided sustained DIZE delivery in vivo, thereby evidencing the potential application of polymeric-based DIZE inserts for glaucoma management.

Biological Activities and Chemical Composition of Methanolic Extracts of Selected Autochthonous Microalgae Strains from the Red Sea.

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 µg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and ß-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value.

In vitro antioxidant and inhibitory activity of water decoctions of carob tree (Ceratonia siliqua L.) on cholinesterases, α-amylase and α-glucosidase.

This work reports the in vitro inhibitory activity of water decoctions of leaves, germ flour, pulp, locust bean gum and stem bark of carob tree on α-amylase, α-glucosidase, acetylcholinesterase and butyrylcholinesterase. The antioxidant activity and the chemical characterisation of the extracts made by spectrophotometric assays and by high-performance liquid chromatography are also reported. Leaves and stem bark decoctions strongly inhibited all the enzymes tested, had significant antioxidant activity and the highest total phenolics content. The major compounds were identified as gallic acid in the leaves and gentisic acid in the stem bark.

Combining bar adsorptive microextraction with capillary electrophoresis--application for the determination of phenolic acids in food matrices.

In this contribution, bar adsorptive microextraction coated with a mixed-mode anion exchange/RP followed by liquid desorption was combined for the first time with a capillary electrophoresis-diode array detection system (BAµE(MAX)-LD/CE-DAD), for the determination of phenolic acids in food matrices, using chlorogenic, ferulic, cumaric, and caffeic acids as model compounds. Assays performed in aqueous media spiked at the 0.8 mg/L level yielded average recoveries up to 40% for all four phenolic acids, under optimized experimental conditions. The analytical performance showed also good precision (RSD < 15%), convenient LODs (18.0-85.0 µg/L) and linear dynamic ranges (0.8-8.0 mg/L) with convenient determination coefficients (r(2) > 0.9900). By using the standard addition method, the application to food matrices such as green tea, red fruit juice, and honey allowed very good performances for the determination of minor amounts of phenolic acids. The proposed methodology proved to be a suitable alternative for the analysis of polar to ionic compounds, showing to be easy to implement, reliable, sensitive, and requiring a low sample volume to determine phenolic acids in food samples.

In vitro antitumoral activity of compounds isolated from Artemisia gorgonum Webb.

Artemisia gorgonum (Asteraceae) is an endemic plant to the Cape Verde islands and plays an important role in traditional medicine. The chloroform extract of the plant aerial parts afforded six sesquiterpene lactones, two methoxylated flavonoids, two lignans, and one tetracyclic triterpene, which were isolated by chromatographic methods and their structure established by physical and spectroscopic techniques. The cytotoxic activity of the three major constituents, namely, arborescin, artemetin, and sesamin, was evaluated on neuroblastoma (SH-SY5Y), hepatocarcinoma (HepG2), and nontumoral bone marrow stromal (S17) cell lines. The application of different concentrations of the compounds significantly decreased tumor cells viability at different extents, especially at the highest concentrations tested. Arborescin is the most promising compound as it was able to reduce tumoral cell viability with an IC50 significantly lower (229-233 µM; p < 0.01) than that of S17 cells (445 µM). Arborescin and artemetin were less toxic to nontumoral cells than the antitumoral drug tested, etoposide. Our results indicate that arborescin has a significant cytotoxic activity in vitro, more pronounced on the cancer cell lines, confirming A. gorgonum as a source of potential antitumoral molecules.

Metabolic profile and biological activities of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco: studies on the essential oil and polar extracts.

We investigated the metabolic profile and biological activities of the essential oil and polar extracts of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco collected in south Portugal. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that oxygen-containing monoterpenes was the principal group of compounds identified in the essential oil. Camphor (40.6%) and fenchone (38.0%) were found as the major constituents. High-performance liquid chromatography with diode array detection (HPLC-DAD) analysis allowed the identification of hydroxycinnamic acids (3-O-caffeoylquinic, 4-O-caffeoylquinic, 5-O-caffeoylquinic and rosmarinic acids) and flavones (luteolin and apigenin) in the polar extracts, with rosmarinic acid being the main compound in most of them. The bioactive compounds from L. pedunculata polar extracts were the most efficient free-radical scavengers, Fe(2+) chelators and inhibitors of malondialdehyde production, while the essential oil was the most active against acetylcholinesterase. Our results reveal that the subspecies of L. pedunculata studied is a potential source of active metabolites with a positive effect on human health.

Chemical composition and bioactivity of different oregano (Origanum vulgare) extracts and essential oil.

BACKGROUND: There is a growing interest in industry to replace synthetic chemicals by natural products with bioactive properties. Aromatic plants are excellent sources of bioactive compounds that can be extracted using several processes. As far as oregano is concerned, studies are lacking addressing the effect of extraction processes in bioactivity of extracts. This study aimed to characterise the in vitro antioxidant and antibacterial properties of oregano (Origanum vulgare) essential oil and extracts (in hot and cold water, and ethanol), and the chemical composition of its essential oil. RESULTS: The major components of oregano essential oil were carvacrol, ß-fenchyl alcohol, thymol, and γ-terpinene. Hot water extract had the strongest antioxidant properties and the highest phenolic content. All extracts were ineffective in inhibiting the growth of the seven tested bacteria. In contrast, the essential oil inhibited the growth of all bacteria, causing greater reductions on both Listeria strains (L. monocytogenes and L. innocua). CONCLUSION: O. vulgare extracts and essential oil from Portuguese origin are strong candidates to replace synthetic chemicals used by the industry.