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Rosmarinus tournefortii is an aromatic evergreen shrub endemic to North Africa, including Algeria. Reports on phytochemicals of this species and related biological activities remain scarce. The essential oils (EOs) and ethanol extracts (EEs) of five populations collected in Algeria are investigated for their antioxidant and antimicrobial properties through different multivariate statistical methods. EOs analysis by GC and GC-MS showed that the main constituents (α-pinene, camphor, camphene and limonene) were almost comparable. The antioxidant capacity was evaluated by the ferric reducing power and the inhibition of free radicals DPPH● and ABTS●+. The free radical scavenging effectiveness of EEs was about 2 times higher than the standard antioxidant (BHT). EOs exhibited weaker antioxidant activity insofar they failed to scavenge 50% radicals. The antimicrobial activity evaluated by determining the minimum inhibitory/bactericidal concentrations towards fifteen multi-drug resistant microorganisms showed that EEs were the most active. The Gram-positive bacteria were the most susceptible. Both EEs and EOs exhibited antifungal and anti-yeast activities.

The essential oils (EOs) of Origanum floribundum Munby, an aromatic and medicinal plant endemic in Algeria, were extracted by different hydrodistillation times (30 min, 1, 2 and 3 h) and analyzed by GC and GC–MS. The chromatographic analysis showed that thymol (32.7–45.0%), p-cymene (16.8–23.1%) and γ-terpinene (21.6–28.7%) were the most prominent components of the oils. The antioxidant ability was measured using the reductive potential, thiobarbituric acid reactive substances (TBARS) assay and the inhibition of free radicals DPPH● and ABTS●+. Antibacterial activity was assessed by the disc diffusion method against three bacteria (Escherichia coli, Staphylococcus aureus and Bacillus subtilis) and one fungus (Candida albicans). Minimal inhibitory concentrations (MICs) were determined using a microdilution method. Thymol is one of the compounds of EOs, which are widely reported as very biologically active. Although the oil isolated for 30 min was the less-thymol rich, it was the most active with all the antioxidant tests. In the most cases, the antimicrobial activity showed the best results with oils isolated for 30 min and 3 h (MIC = 0.25–1.75 μL/mL). These results suggest that it might be possible to isolate the EO from this plant for a minimum distillation time to obtain oil that can give maximum biological activities.

Methanolic extracts (MEs) and essential oils (EOs) of the aerial parts of two samples of the Algerian endemism Origanum floribundum Munby collected at the beginning of the leafing stage from two di...

A possible way to valorize citrus peels, which are byproducts of the juice extraction industry, is to use them as natural biopreservatives. In this paper we present early results from a compared Solvent Free Microwave Extraction (SFME) with Hydro-Distillation (HD) and Cold Pressing (CP) of essential oils (EOs) using fresh orange peel (Citrus sinensis L. var. Valencia late), a by-product in the production of orange juice in Algeria. The EOs were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). All extracted C. sinensis EOs were chemotype limonene (94.64 to 95.48%). SFME is performed without added any solvent or water. SFME increases EO yield and eliminate wastewater treatment, resulting in a great progress in terms of time and cost efficiency. In its second part, the present study was conducted to evaluate “in vitro”, the antioxidant activities of Solvent Free Microwave (SFM) extracted orange EO by using the DPPH• (2,2-di-phenyl-1-picrilhydrazyl) free radical scavenging assay. The ability of orange EO to scavenge the free radical DPPH• was high, exceeding 80%. The result of the DPPH assay gives an IC50 range value of 89.25 μg/mL (0.09 mg/mL) for the studied sample. Accordingly to the scientific literature, C. sinensis EO tested in the present study presented strong antioxidant activity, when looking to its values of AAI = 1.12 μg/mL. The feasibility of biopreservation used EOs as an alternative to synthetic techniques for liquid whole egg (LWE) stored under commercial retail conditions was investigated. The orange EO extracted by SFM was screened for its antibacterial and antioxidant activities in LWE at concentrations of 0.1, 0.3 and 0.5%. The TBA-RS results showed that the EO treatments significantly (p < 0.05) reduced the lipid oxidation in LWE. The long term oxidative, microbial and organoleptical stability of the LWE during display was positively influenced by orange EO treatments. Therefore, the results obtained here confirm that EO treatment as a promising technology to extend the commercial shelf-life of liquid egg products during retail/display.

The essential oils (EOs) of Cymbopogon schoenanthus (L.) collected from six regions of the vast Algerian Sahara were analyzed for their chemical compositions by GC and GC-MS and tested for their an...

The essential oils isolated by hydrodistillation from Thymus pallescens de Noe dried leaves exposed to γ-irradiation at dose levels of 0, 5, 10, 20, and 30 kGy were analyzed by gas chromatography–flame ionization detector (GC–FID) and GC–mass spectrometry (MS) and tested for their antioxidant, antimicrobial, and insecticidal activities. No qualitative change was observed in the chemical composition. Carvacrol (81.8–85.7%) was the most prominent component. Gamma-irradiation at 20 kGy affects quantitatively some components. Antioxidant activity was evaluated by four different test systems, namely, inhibition of lipid peroxidation (thiobarbituric acid reactive substance, TBARS), ferric reducing power, and scavenging of radicals DPPH• and ABTS•+. In all systems, irradiated oils at 20 and/or 30 kGy showed the most antioxidant efficiency. Overall, the antimicrobial activity conducted against seven microorganisms revealed no significant changes according to the radiation dose. Fumigation bioassays and contact me...

The aim of the present study was the evaluation of the phytotoxic effect of essential oils (EOs) from two Labiatae species, namely Thymus fontanesii Boiss. et Reut. and Satureja calamintha subsp. n...

The essential oils (EOs) of

BACKGROUND: Teucrium polium L. aerial parts are traditionally used in Algerian folk medicine due to its therapeutic properties. OBJECTIVE: The present study was designed to evaluate the effect of different extracting solvents (methanol, ethanol, ethyl acetate, chloroform, hexane and water) on antioxidant capacity and total phenol and flavonoid contents of Algerian Teucrium polium aerial parts. METHODS: The antioxidant capacity of Teucrium polium extracts was assessed by DPPH (2, 2-diphenyl-1-picrylhydrazyl) and ABTS (2, 2’-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid) free radicals scavenging and reducing power assays. For each extract, the total phenol and flavonoid contents were investigated by the Folin-Ciocalteu and aluminium trichloride methods, respectively. RESULTS: All the tested extracts showed an appreciable total phenolic and total flavonoid contents and strong antioxidant capacity. Among the different extracts, the methanolic extract was found to be containing the highest amount of total phenols (206.95±1.82 mg of gallic acid equivalent per gram of extract) and flavonoids (42.16±0.61 mg of quercetin equivalent per gram of extract). The same extract also exhibited a much better reducing power and scavenging capacity against DPPH (IC50 = 6.77±0.15 mg/l) and ABTS (IC50 = 2.79±0.07 mg/l). CONCLUSION: These findings suggest that aerial parts of Teucrium polium methanolic extract could be used as natural source of antioxidants in food, pharmaceutical and cosmetic industry.

Thymus algeriensis Boiss. et Reut. pretreated with gamma irradiation at the doses of 0, 10, 20 and 30 kGy were submitted to hydrodistillation and the resulted essential oils were analyzed for their chemical composition by GC and GC-MS and for their antioxidant activity evaluated by inhibition of lipid peroxidation, ferric reducing antioxidant power and scavenging of radicals DPPH• and ABTS•+. On the other hand, the non volatile ethanol extracts obtained by Soxhlet, were analyzed in terms of the dosage of total phenols and flavonoids and for their antioxidant activity. Although there were no qualitative changes in the chemical composition of the essential oils of the irradiated samples, minor quantitative changes were observed for some compounds for some irradiation doses, especially for the three main components: carvacrol for all the doses in addition to p-cymene and γ-terpinene for 10 kGy and γ-terpinene for 30 kGy. The antioxidant activity of the oils was dependent on the method employed to det...

Response surface methodology (RSM) was used for the first time to investigate the efficiency of a new process developed in our laboratory: Microwaves Steam Distillation (MSD) on the oregano essential oil extraction. The selected parameters are steam flow, microwave power and extraction time, the response is essential oil yield. According to the statistical method, a second-order polynomial function was assumed to approximate the yield. The coefficient of determination R2 (91.33%), revealed a quite agreement between experimental and predictive values. Optimal conditions were: 6 g. min-1 for steam flow, 300 W for microwave power and 8 min for time. DPPH tests showed that MSD oil was the most efficient than eugenol, SD oil and the main compounds (carvacrol and thymol), and has comparable antioxidant activity to that of BHT. In the other hand, MSD and SD oils have an insecticidal effect against Rhizopertha dominica, but SD oil was most efficient.

The present work investigates the chemical composition and in vitro antioxidant activity of essential oils from leaves of Rosmarinus tounefortii De Noe and Lavandula stoechas L. grown in Algeria and to assess their bioactivity on Callosobruchus maculatus (F.). The essential oils of these plants were obtained by hydrodistillation (yield=1.6 and 0.16 ml/100 g of fresh weight for R. tounefortii and L. stoechas, respectively). GC and GC-MS revealed fenchone (24.7%), camphor (6.9%) and bornyl acetate (6.3%) as major compounds of L. stoechas essential oil, while the rosemary oil was dominated by camphor (39.4%), α-pinene (10.4%) and p-cymene + limonene (11%). Antioxidant activity was assessed in vitro using two different tests: Reducing power and scavenging activity of the free radical DPPH. For both tests, results revealed that studied essential oils exhibited lower antioxidant activity compared to the synthetic antioxidant butylated hydrxytoluene (BHT). The evaluation of the insecticidal activity show...

The present study was conducted to evaluate the in vitro antioxidant, anti-inflammatory and antimicrobial activities of the essential oils and crude ethanol extracts of Teucrium polium subsp. capitatum Briq. and Origanum floribundum Munby from Algeria. A total of 78 and 55 constituents were identified, representing 92 and 98.4 % of the total chemical composition of Teucrium and Origanum essential oils, respectively. Monoterpenes (22 %), sesquiterpenes (31.2 %) and oxygenated sesquiterpenes (25.5 %) dominated in the oil of T. polium with t-cadinol (18.3 %), germacrene D (15.3 %) and β-pinene (10.5 %) as predominant compounds; while monoterpenes (51.3 %) and oxygenated monoterpenes (45.2 %) were the most prominent groups in O. floribundum oil characterized by thymol (33.6 %), γ-terpinene (19.9 %) and p-cymene (15.5 %). The ethanol extracts were analyzed in terms of the dosage in total phenolic and flavonoids contents. Gallic acid equivalent representing total phenolic constituents of the extracts of...

Thymus pallescens de Noe essential oils were isolated from the plant’s dried leaves, by hydrodistillation, with different distillation times (30 min, 1, 2 and 3 h). The essential oils compositions and their antioxidant, antimicrobial and insecticidal activities were examined. The chemical compositions of the oils were determined by GC and GC-MS. The antioxidant capacity was tested by four complementary methods: thiobarbituric acid reactive substances, ferric reducing power and scavenging of radicals DPPH• (2,2-diphenyl-1-picrylhydrazyl) and ABTS•+ [2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid)]. The antimicrobial activity was tested against three bacteria, two gram-positive (Staphylococcus aureus and Bacillus subtilis) and one gram-negative (Escherichia coli) and one yeast (Candida albicans). The insecticidal activity against confused flour beetle Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) was evaluated using direct contact application and fumigant method. The predominant components in the oils were carvacrol (63.3–68.2 %), γ-terpinene (6.9–9.1 %), p-cymene (6.2–10.3 %) and thymol (6.5–7.5 %). The antioxidant activities were dependent on the time of hydrodistillation and the method used. The essential oils extracted for 30 min and 1 h were the most efficient against all the bacteria used. Toxicity tests against T. confusum showed that the oils isolated for 3 h and 30 min caused highest mortality with contact method and fumigant test, respectively. The results suggest that distillation time can determine the value of the oil designed to be applied to any biological material.

This study was designed to examine the in vitro antioxidant and antimicrobial activities of ethanol extracts and essential oils of three samples of Rosmarinus officinalis L. from different origins of Algeria. The compositions of the essential oils obtained by hydrodistillation were investigated by GC and GC-MS. A total of eighty components were identified in the oils and the main components of two samples were α-pinene (24.7-51.0 %), limonene (4.5-14.3 %) and camphor (7.8-13.8 %), while the third one was characterized by camphor (32.0 %), camphene (22.0 %) and α-pinene (20.9 %) as the main components. The antioxidant capacity of the oils and ethanol extracts was examined using an in vitro radical scavenging test and reducing power. In the 2,2-diphenylpicrylhydrazyl (DPPH) test system, ethanol extracts exhibited more efficiency (IC50=10.4-20.7 mg/l) than butylated hydroxytoluene (BHT) (IC50=28±0.7 mg/l). In contrast, essential oils were less effective than BHT and failed to scavenge 50 % DPPH radic...

Antioxidant efficiency and chemical constituents of Thymus Pallescens de Noe essential oil were examined. Also, the effect of thermal treatments (100°, 150° and 190°C) for 3 hours on the antioxidant activity and chemical constituents of the oil was studied. Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH•) free-radical scavenging and reducing power, and compared with synthetic antioxidant (butylated hydroxytoluene, BHT) and the oil kept at room temperature. The main compounds were carvacrol (42.9–44.1%), p-cymene (10–11%) and γ-terpinene (7.9–10.5%). The oils being heated did not significantly affect for their chemical composition. The antioxidant activities were dose-dependent and varied with the temperature and the method used.

Two samples of essential oils from the leaves and cones of wild Tetraclinis articulata (Vahl.) Masters from two different sites in Algeria were isolated by hydrodistillation and investigated by gas chromatography (GC) and GC/mass spectrometry (GC/MS). A total of forty compounds were identified representing 98.6–99.8% of the oils. The main components of the volatile oils were α-pinene (19.8–24.9%) and bornyl acetate (40.2–59.2%) for the leaves, α-pinene (57.5–75%), limonene (10.6–20.9%) and β-myrcene (3.6–10.6%) for the cones. The antioxidant efficiency was tested using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method. In comparison with butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), which were used as positive controls, all samples showed weak activity. The antimicrobial activities of the essential oils were assayed by using the disc diffusion method and agar dilution technique on Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus...

The essential oil of Algerian Satureja calamintha subsp. nepeta (L.) Briq. obtained by hydrodistillation, was investigated using both capillary GC and GC-MS techniques and assayed for its antimicrobial and antioxidant activities. Twenty six components representing 98.2 % of the oil were characterized. Oxygenated monoterpenes (97.4 %) was the predominant class with pulegone (39.5 %), neo-menthol (33 %) and isomenthone (19.6 %) as major constituents. The antimicrobial activity of the oil was assessed by the disc diffusion method against six bacteria and two fungi. Minimal inhibitory concentrations (MIC) were determined by using the agar dilution against the sensitive microbial species, the results of the antimicrobial assays showed that Staphylococcus aureus was the most sensitive bacteria to this oil (MIC=0.25 %). The antioxidant activities of the essential oils were evaluated by DPPH free radical-scavenging and reducing power. For both tests, S. calamintha oil showed a low activity, which was less...

Essential oils of Algerian Juniperus phoenicea L. obtained from leaves and berries by hydrodistillation (HD) and from berries by Solvent Free Microwave Assisted Extraction (SFMAE) were investigated using both capillary GC and GC-MS techniques. The monoterpene hydrocarbons constituted the most prominent group of constituents (43.2-86.5 %) in the three essential oils with α-pinene (34.4-80.8 %) as the main compound. Leaves ethanol extract was analyzed in terms of the dosage in total phenolic and flavonoids contents. Gallic acid equivalent representing total phenolic constituents of the extract was 308 mg GAE/g; and quercetin equivalent representing total flavonoids was 20 mg QE/g. The antioxidant potential of the samples was evaluated using two separate methods, inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power. All essential oils showed a relatively weak antioxidant capacity. No improvement of the antioxidant activity by SFMAE technique has been detected. J. phoenicea ethan...

The essential oils from leaves of Thymus munbyanus Desf. and Ferula vesceritensis Coss et Dur. were analyzed by GC and GC-MS and assayed for their antioxidant activities. Eighty nine components representing 93 - 96.8 % of the oils were characterized. Sesquiterpene hydrocarbons (37.0 %) and oxygen-containing sesquiterpenes (47.8 %) were the predominant classes in the oil of F. vescertentis with viridiflorol (13.4 %), δ-cadinene (10.1 %) and famesol (8.1 %) as major constituents; while oxygen-containing monoterpenes (66.4 %) was the most prominent group in T. munbyanus oil with carvacrol (35.2 %) and thymol (18.5 %) as the main constituents. The antioxidant activities of the essential oils were evaluated by DPPH free radical-scavenging and thiobarbituric acid reactive substances (TBARS) assays. For both tests, T. munbyanus oil showed potent activity, similar to that of BHT, mainly for high concentrations, whereas F. vesceritensis oil showed moderate activity.

The genus Origanum L. (Lamiaceae) enjoys a socioeconomic interest and constitutes one of the most popular spices. In the literature, the study of this taxon is limited mainly to the chemical composition, antimicrobial, antifungal, and antioxidant activities of the essential oils. In Algeria, few works have been done in this area, including the endemic and rare species: Origanum floribundum Munby. In this study, our contribution highlights the influence of the ecological parameters and of the variation of morphological traits on the chemical composition and the antioxidant activity of the essential oils of six populations. The major oils constituents are carvacrol, γ-terpinene, and p-cymene with carvacrol predominance (31.8 - 60.8%) in over five populations (MS1 - MS4 and MS6). However, the population of Ain Terraeur (MS5) of which individuals present a foliar polymorphism, distinguishes itself by p-cymene predominance (42.6%). This would denote a new chemotype and/or variety which seem well differentiated on the dendrogram of the Ascending Hierarchical Classification (A.H.C) and its foliar morphology. The antioxidant activity of the six samples evaluated by the scavenging activity of free radicals DPPH(•) and ABTS(•+) showed a potent efficiency for the sample with foliar polymorphism population (IC50 = 51.6 ± 0.31 and 12.71 ± 0.37 μg/ml, respectively).

The current study aimed to evaluate the negative allelopathic effect of Eucalyptus citriodora essential oil on some of the most noxious weeds in Algeria (Sinapis arvensis, Sonchus oleraceus, Xanthium strumarium and Avena fatua). Gas chromatography-flame ionization detector (GC-FID) and GC/mass spectrometry (MS) were used to define the chemical composition of the oil. Citronellal (64.7%) and citronellol (10.9%) were the major essential oil compounds. Three concentrations of the oil were used for laboratory (0.01, 0.02 and 0.03%) and greenhouse (1, 2 and 3%) experiments. Seed germination and seedling's growth were drastically reduced in response to the oil concentrations where at 0.01 and 0.02% the oil drastically affects the seed germination of the tested weeds and at 0.03% the oil suppresses completely the germination of S. arvensis. The oil also exhibited strong allelopathic effect on the 3 - 4 leaf-stage plants 1 and 6 days after treatment. A completely death of S. arvensis, S. oleraceus and A. fatua and severe injuries on X. strumarium appeared at 3% of the oil. Chlorophyll content and membrane integrity were significantly affected after treatment of the plant weeds representing a severe reduction in total chlorophyll and cell membrane disruption. The study concludes that E. citriodora essential oil might has the potential use as bioherbicide and can constitute an alternative process of weed control.

Three different extraction methods were used for a comparative study of essential oil from fresh Citrus peels: Traditional hydrodistillation (HD), cold pressing (CP) and innovative microwave ‘dry’ distillation or microwave-accelerated distillation (MAD). The microwave method offers important advantages over traditional alternatives, viz. shorter extraction times (30 min vs. 3 h for hydrodistillation and 1 h for cold pressing); better yields (0.24% vs. 0.21% for HD and 0.054% for CP); environmental impact (energy cost is appreciably higher for performing HD and for mechanical motors (CP) than that required for rapid MAD extraction); cleaner features (as no residue generation and no water or solvent used); increases antimicrobial activities; and provides a more valuable essential oil (with high amounts of oxygenated compounds).

The compositions of essential oils isolated from nine samples of three Thymus species (Thymus algeriensis, Thymus pallescens and Thymus dreatensis) were analysed by GC and GC-MS, and a total of 114 components were identified. T. pallescens collected from various regions showed a great similarity in their compositions and were characterised by carvacrol (44.4-57.7%), p-cymene (10.3-17.3%) and gamma-terpinene (10.8-14.2%) as the major components for four samples; only one sample was thymol-rich (49.3t) with a small amount of carvacrol (9.0%). On the other hand, T. algeriensis showed a chemical polymorphism, even for samples from the same location, and two new chemotypes for this species were proposed. Oxygen-containing monoterpenes were the predominant class (76.3%) in T. dreatensis oil, with linalool (30.4%), thymol (20.2%) and geraniol (19.6%) as the principal constituents. The oils were screened for their possible antioxidant activities by four complementary assays, namely DPPH free radical scavenging, hydroxyl radical scavenging, inhibition of lipid peroxidation and reducing power. The two new chemotypes of T algeriensis exhibited strong hydroxyl radical scavenging (IC(50) = 2.2-3.3 mu g/ml), but were not or only slightly active against the other radicals and exhibited a weak reducing power. Despite their chemical similarity, T. pallescens oils sometimes produced significant differences in their antioxidant activities. The essential oils were also screened for their antimicrobial activity against five bacteria (three Gram-positive and two Gram-negative) and one yeast (Candida albicans). The tested essential oils showed antimicrobial activity against the microorganisms used, in particular against two important pathogens, C. albicans and Helicobacter pylori. (C) 2009 Elsevier Ltd. All rights reserved.

The essential oils of Thymus pallescens de Noe and Origanum floribundum Munby leaves and flowers were analyzed by GC and GC/MS. The oil yields of T. pallescens were 2.8% for the leaves and 3.7% for the flowers, while those of O. floribundum were 2.0% for the leaves and 5.4% for the inflorescences. The major constituents of both the leaves and flowers of T. pallescens were p-cymene (17.4% and 9.2%), γ-terpinene (10.6% and 14.1%) and carvacrol (39.0% and 48.3%), respectively, while those of O. floribundum were p-cymene (22.3% and 9.6%), γ-terpinene (17.3% and 24.3%) and thymol (34.4% and 41.2%), respectively. For the both plants p-cymene and sesquiterpenes were essentially concentrated in leaves.

The yield and composition variation of the essential oil from Thymus pallescens de Noe were determined. This endemic species growing in Algeria was harvested at three stages of plant development during four successive years (2003–2006). The yield in essential oil showed a maximum in the full flowering stage (4.2–4.6%) and a minimum at the beginning of the vegetative cycle (0.9–1.3%). Analysis was performed by GC and GC/MS. Carvacrol (39.7–65.0%) was found to be the most abundant constituent at each harvest period, followed by p-cymene (5.1–15.1%) and γ-terpinene (6.1–17.4%). At the vegetative period the essential oil was the richest in carvacrol (51.1–65.0%). At the full flowering period the oils of whole years reached close amounts of the main constituents and of different classes of components.

The Algerian flora contains a wide variety of plant species with potential to be used in medicinal applications. Herein, the bioactive properties of medicinal plants from Algeria were evaluated to select the species with highest suitability to be used under specific purposes, while scientifically validating their health claims. The antioxidant activity of the infusions was screened by using several tests and cytotoxic properties were evaluated against human tumor cell lines (as also against non-tumor cells). Different hydrophilic bioactive compounds were also quantified. The results were analyzed considering individual variations in each parameter (ANOVA), but also in an aggregated approach by applying principal component analysis to acquire a comprehensive knowledge regarding the overall bioactive potential of the studied species. Limoniastrum guyonianum and Thymus pallescens showed the highest antioxidant activity (EC50 values ranging from 29 to 229 μg/mL and 54 to 240 μg/mL, respectively), whilst Asteriscus graveolens and L. guyonianum gave the best cytotoxicity against human tumor cell lines (GI50 values ranging from 11 to 29 μg/mL and 22 to 70 μg/mL, respectively). T. pallescens stood out as the species with highest bioactive compounds contents (phenols: 463 mg GAE, flavonoids: 194 mg CE, esters; 186 mg CAE; flavonols: 85 mg QE, considering g of lyophilized infusion basis). From a global point of view, T. pallescens, Saccocalyx satureioides and Ptychotis verticillata proved to be the preferable choices as high potential sources of bioactive compounds, while Haloxylon scoparium, L. guyonianum and A. graveolens would be the most suitable matrices considering the bioactivity (especially cytotoxicity) criterion, as inferred from the PCA outputs. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to CIMO (PEst-OE/AGR/UI0690/2014), R.C. Calhelha (SFRH/BPD/68344/2010), J.C.M. Barreira (SFRH/BPD/72802/2010) and L. Barros (“Compromisso para a Ciência 2008” contract).

The composition of the essential oils of Origanum and Thymus species restricted to Algeria and the North Africa region was determined. Antioxidant and antibacterial activities of the isolated essential oils were also determined. The oils of oregano plants were strongly characterized by p-cymene (16.8-24.9%), gamma-terpinene (16.8-24.9%), thymol (8.4-36.0%), and carvacrol (1.1-29.7%), a thymol chemotype for Origanum floribundum and a alpha-terpineol chemotype for Thymus numidicus being described for the first time. The strains of Listeria monocytogenes tested were relatively resistant to the action of essential oils of either Origanum or Thymus species. All essential oils possessed antioxidant activity, but this was dependent on the specific chemical composition and the method employed to determine such activity.

Traditional medicine has been used worldwide for centuries to cure or prevent disease and for male or female contraception. Only a few studies have directly investigated the effects of herbal compounds on spermatozoa. In this study, essential oil from Thymus munbyanus was extracted and its effect on human spermatozoa in vitro was analysed. Gas chromatography and Gas chromatography – mass spectrometry analyses identified 64 components, accounting for 98.9% of the composition of the oil. The principal components were thymol (52.0%), γ-terpinene (11.0%), ρ-cymene (8.5%) and carvacrol (5.2%). Freshly ejaculated spermatozoa was exposed from control individuals to various doses of the essential oil for different time periods, and recorded the vitality, the mean motility, the movement characteristics (computer-aided sperm analysis), the morphology and the ability to undergo protein hyperphosphorylation and acrosomal reaction, which constitute two markers of sperm capacitation and fertilizing ability. In vitro , both the essential oil extracted from T. munbyanus and thymol, the principal compound present in this oil, impaired human sperm motility and its capacity to undergo hyperphosphorylation and acrosome reaction. These compounds may, therefore, be of interest in the field of reproductive biology, as potential anti-spermatic agents.