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Background: The effects of vegetable oils on human health depend on their components. Therefore, their profiles of lipid nutrients and polyphenols were determined. Objective: To establish and compare the fatty acid, tocopherol, phytosterol and polyphenol profiles of Mediterranean oils: cosmetic and dietary argan oils (AO; Morocco: Agadir, Berkane); olive oils (OO; Morocco, Spain, Tunisia); milk thistle seed oils (MTSO; Tunisia: Bizerte, Sousse, Zaghouane); nigella seed oil (NSO). Methods: The biochemical profiles were determined by gas chromatography-flame ionization, high performance liquid chromatography and gas chromatography, coupled with mass spectrometry as required. The antioxidant and cytoprotective activities were evaluated with the KRL (Kit Radicaux Libres) and the fluorescein diacetate tests on nerve cells treated with 7-ketocholesterol (7KC). Results: The fatty acid profile revealed high linoleic acid (C18:2 n-6) content in AO, OO, MTSO and NSO. The highest levels of oleic acid (C18:1 n-9) were found in AO and OO. The tocopherol profile showed that Agadir AO contained the highest amount of α-tocopherol, also present at high level in MTSO and Tunisian OO; Berkane AO was rich in γ-tocopherol. The phytosterol profile indicated that β-sitosterol was predominant in the oils, except AO; spinasterol was only present in AO. Polyphenol profiles underlined that OO was the richest in polyphenols; hydroxytyrosol was only found in OO; few polyphenols were detected in AO. The oils studied have antioxidant activities, and all of them, except NSO, prevented 7KC-induced cell death. The antioxidant characteristics of AO were positively correlated with procatechic acid and compestanol levels. Conclusion: Based on their biochemical profiles, antioxidant and cytoprotective characteristics, AO, OO, and MTSO are potentially beneficial to human health.

Background The in vitro activity of the brown seaweed Dictyota spiralis against both Leishmania amazonensis and Trypanosoma cruzi was evaluated in a previous study. Processing by bio-guided fractionation resulted in the isolation of three active compounds, classified as diterpenes. In the present study, we performed several assays to detect clinical features associated to cell death in L. amazonensis and T. cruzi with the aim to elucidate the mechanism of action of these compounds on parasitic cells. Methods The aims of the experiments were to detect and evaluate specific events involved in apoptosis-like cell death in the kinetoplastid, including DNA condensation, accumulation of reactive oxygen species and changes in ATP concentration, cell permeability and mitochondrial membrane potential, respectively, in treated cells. Results The results demonstrated that the three isolated diterpenes could inhibit the tested parasites by inducing an apoptosis-like cell death. Conclusions These results encourage further investigation on the isolated compounds as potential drug candidates against both L. amazonensis and T. cruzi. Graphical Abstract

The main concern of this work was to find a new biological antisprouting product for potatoes during storage. Ruta chalepensis L. essential oil (RCEO) was for the first time used as a potential sprouting inhibitor for potatoes. To confirm RCEO antisprouting effect, evolution of sprout length and weight loss of potato tubers was determined during a storage period of six weeks under three RCEO different treatments (2%, 4%, and 6%). Sprout final weight was also computed. Then, a screening of RCEO chemical composition was performed. An outstanding antisprouting effect of 6% emulsions concentrations was observed as compared to 2% and 4% emulsions concentrations. Final sprout weight (SW) of untreated samples was 4.66%, while 6% treated samples scored 0.98%. These results were endorsed by high Pearson correlation coefficients (>0.9). Indeed, increasing treatment concentration enhanced the sprout growth inhibition. Identification of RCEO major components showed that 2-undecanone represented 87.18% of total identified components suggesting that this component is the possible active agent of RCEO against potatoes sprouting.

Free-living amoebae of genus Acanthamoeba are opportunistic pathogens widely distributed in the environment, and are the causative agents of several humans’ infections, such as Acanthamoeba keratitis, Granulomatous Amoebic Encephalitis and also disseminated infections. The existence of the cyst stage complicates Acanthamoeba therapy as it is highly resistant to antibiotics and physical agents. All these facts reinforced the necessity to find and develop an effective therapy against Acanthamoeba infections. In the present study, we are interested to several seaweeds species collected from the Tunisian coasts and belonging to the 3 phyla (brown, green and red algae). The aim was to quantify the Total Phenolic Compounds in different organic extract, to evaluate antioxidant capacity (DPPH and ABTS) and to study the antiprotozoal activity against A. castellanii Neff. The parasites have been inhibited by all extracts with an IC50 ranged from 52,3±1.8 μg/mL for ethyl acetate extract, to 134,6±0.7 μg/mL for the hexanic one for the various species studied.

Plants are a source of bioactive compounds such as antioxidants and enzyme inhibitors. In this work, effect of the Eucalyptus globulus and Mentha viridis extraction by different solvents on phenolics content, flavonoids content, condensed tannins content, antioxidant activity and inhibitory effect against two lipases from Aspergillus niger and olive was studied. Methanolic (MeOH) extract showed the strongest antioxidant and anti-lipase activities. High correlation between total phenolics content, total flavonoids content, antioxidant activity and lipases inhibitory action was observed. Kinetic analysis of lipases inhibition was performed with Linweaver-Burk, Dixon and Cornish-Bowden plots. These results revealed competitive inhibition mode by E. globulus and non competitive mixed inhibition mode by M. viridis against the two lipases. Inhibition constant (KI) values calculated with E. globulus MeOH extract were 0.271 and 0.188 mg/mL for Aspergillus niger and olive lipases respectively. With M. viridis MeOH extract KI values were 0.303 and 0.421 mg/mL for the fungal and the plant lipases respectively. The inhibitory concentration 50% (IC50) values determined with E. globulus MeOH extract were 0.69 mg/mL for Aspergillus niger lipase and 1.29 mg/mL for olive lipase. With M. viridis MeOH extract IC50 were 0.43 and 1.44 mg/mL for Aspergillus niger and olive lipases respectively.

The Asteraceae family is economically very important, because many of these plants are grown mainly for their food value, such as lettuce (Lactuca), chicory (Cichorium), and sunflower (Heliantus aminus). One of the typical properties of this family, which includes milk thistle (Sylibum marianum), is the richness of the oil in various compounds (flavonoids, alkaloids, tocopherols, and unsaturated fatty acids). Currently, and for the coming decades, age-related diseases, including neurodegenerative diseases, are a major public health problem. Preventing their appearance or opposing their evolution is a major objective. In this context, the cytoprotective activities of milk thistle seed oil produced in Tunisia were studied on the 158N model using 7-ketocholesterol (7KC) and 24S-hydroxycholesterol (24S) as cytotoxic agents. 7KC and 24S were used because they can be increased in the brain and body fluids of patients with major age-related neurodegenerative diseases, such as Alzheimer&rsquo, s and Parkinson&rsquo, s diseases. In order to evaluate the cytoprotective properties of milk thistle seed oil, complementary techniques of microscopy, flow cytometry, and biochemistry were used. The chemical composition of milk thistle seed oil has also been determined by various chromatography techniques. Milk thistle seed oils from different area of Tunisia are rich in tocopherols and are strongly antioxidant according to various biochemical tests (KRL (Kit Radicaux Libres), FRAP (Ferric Reducing Antioxidant Power), and DPPH (2,2-diphenyl-1-picrylhydrazyl)). The main fatty acids are linoleic acid (C18:2 n-6) and oleic acid (C18:1 n-9). The main polyphenols identified are homovanillic acid, p-coumaric acid, quercetin, and apigenin, with a predominance of vanillic acid. On 158N cells, milk thistle seed oil attenuates the cytotoxicity of 7KC and 24S including: loss of cell adhesion, increased plasma membrane permeability, mitochondrial dysfunction, overproduction of reactive oxygen species, induction of apoptosis, and autophagy. The attenuation of the cytotoxicity of 7KC and 24S observed with the milk thistle seed oil is in the order of that observed with &alpha, tocopherol used as a positive control. In the presence of nigella seed oil, considered potentially cytotoxic, no cytoprotective effects were observed. Given the chemical characteristics, antioxidant properties, and cytoprotective activities of milk thistle seed oil, our results highlight the potential benefit of this oil for human health.

The aim of this work is to study the use of Ruta chalepensis essential oil as a bioactive substance in order to propose ways of valuation and rational exploitation of the plant. In this context, the extraction of essential oil was carried out using hydrodistillation process. 23 compounds were identified in the aerial part of Ruta chalepensis essential oil. The major compound is undecan-2-one (77.7 %). In addition, the phytotoxic activity of Ruta chalepensis essential oil was investigated. An important toxicity on the germination of the hard wheat was observed. Indeed, the rate of hard wheat germination passes from 65.55 % at 0.5 μ1.ml−1 essential oil concentration to 31.11% at 1 μ1.ml−1.

To evaluate the effects of hydrodistillation parameters and the vegetative cycle of the plant (Ruta chalepensis L.) on the global essential oil yield the response surface methodology was used. The parameters tested are the volume of water in the suspension to be distilled and the time of distillation. The third parameter is the vegetative cycle of the plant. The responses were the global extraction yield and the extraction yield of following essential oil compounds: 2-undecanone, 2-decanone, 2-dodecanone and 2-tridecanone. The optimal conditions selected for the total output of the extraction obtained from the analysis of the response surfaces are: time of distillation: 120 minutes; volume of water in the suspension to be distilled: 500 ml; stage of vegetation: January (young growths). The results show that the time of distillation and the stage of vegetation are the parameters more meaning on the global essential oil yield.

The extraction of essential oil was carried out using two processes: hydrodistillation and supercritical CO2 extraction. The chemical composition of extracted essential oil was determined. The yield of extraction by supercritical CO2 was about 7.8 %. This yield is more important than that obtained by hydrodistillation process (5.51 %). The chemical composition of the supercritical CO2 extract indicates the presence of only two compounds. The major one is undecan-2-one (100 %). The second one is limonene which is present as trace. However, 23 compounds were identified in the essential oil of the aerial part of Ruta chalepensis extracted by hydrodistillation process. The major compound is also undecan-2-one (77.7 %).

The aim of this work was to select strains with proteolytic activity on wheat gliadin, among lactic acid bacteria, previously isolated from Tunisian fermented wheat dough. Hydrolysis of gliadin, as sole nitrogen source, in an agar medium was visualized by a clear zone surrounding colonies. The increase in absorbance due to gliadin breakdown was measured spectrophotometrically using O-phthaldialdehyde (OPA) on Gliadin Glucose Broth medium. Fermented liquid dough inoculated with individual selected Enterococcus faecalis, showed a decrease of the gliadin concentration from 45 g/kg to 18 g/kg determined by sandwich ELISA test (R-7001). Only the enterococci strains show an hydrolysis of gliadin proteins. Strains showing proteolytic activity are gaining more and more importance in cereal based fermented foods and may help to reduce gliadin involved in coeliac disease.

6cfu/g of mesophilic aerobic bacteria (MAB). Lactic acid bacteria (LAB) and yeasts dominated the microflora of these samples. They varied from 10 5 to 10 8 cfu/g. The LAB/yeasts ratio arising from microbial counts were varied between 1/1 and 200/1. More than 50% of the analysed samples were deprived of Enterococcus. The content of contaminating microflora like coliforms and mesophilic Bacillus ranged from 10 2 to 10 4 cfu/g. The ratio

Therapy against Acanthamoeba infections such as Granulomatous Amoebic Encephalitis (GAE) and Acanthamoeba Keratitis (AK), remains as an issue to be solved due to the existence of a cyst stage which is highly resistant to most chemical and physical agents. Recently, the activity of Olive Leaf Extracts (OLE) was demonstrated against Acanthamoeba species. However, the molecules involved in this activity were not identified and/or evaluated. Therefore, the aim of this study was to evaluate the activity of the main molecules which are present in OLE and secondly to study their mechanism of action in Acanthamoeba. Among the tested molecules, the observed activities ranged from an IC50 of 6.59 in the case of apigenine to an IC50 > 100 μg/ml for other molecules. After that, elucidation of the mechanism of action of these molecules was evaluated by the detection of changes in the phosphatidylserine (PS) exposure, the permeability of the plasma membrane, the mitochondrial membrane potential and the ATP levels in the treated cells. Vanillic, syringic and ursolic acids induced the higher permeabilization of the plasma membrane. Nevertheless, the mitochondrial membrane was altered by all tested molecules which were also able to decrease the ATP levels to less than 50% in IC90 treated cells after 24 h. Therefore, all the molecules tested in this study could be considered as a future therapeutic alternative against Acanthamoeba spp. Further studies are needed in order to establish the true potential of these molecules against these emerging opportunistic pathogenic protozoa.

Background Thymus algeriensis Boiss. et Reut. (Lamiaceae), popularly known as “mougecha” or “mazoukcha” is prolific in Mediterranean regions, mostly in North Africa, and is used in folk medicine to treat of stomach diseases. Methods In this study, animals were induced with gastric ulcers using HCl/ethanol (0.3 M HCl/60% ethanol) and treated orally with essential oil of Thymus algeriensis (EOTa) in various doses ranging from 54 mg/kg body weight to 180 mg/kg body weight. Result The dose found to be effective was 180 mg/kg body weight, since this dose brought about a maximum reduction in lesion index in female rats. In gastric tissues, levels of total glutathiones (GSH, GST and GPx) and thiobarbituric acid reactive substances (TBARS) were evaluated. The activities of the antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD) were measured. Histopathological changes were observed using a cross section of gastric tissue. Chemical analysis revealed the presence of 13 components accounting for 77.7% of the essential oil from dried leaves. Oral administration of EOTa (54, 117 and 180 ml/kg) inhibited HCl/ethanol-induced ulcers. Lesion index was significantly reduced in ulcer induced animals treated with EOTa (HCl/ethanol + EOTa) compared to those ulcerated with HCl/ethanol but with no treatment given. Females showed a greater resistance to ulcers and gastric lesions occurred less often than in males. GSH, pH, enzymic antioxidants, and adherent mucus content were all significantly increased. Conclusion From the data presented in this study, it can be concluded that male rats are more sensitive to gastric ulcers induced by HCl/ethanol than females.

Protozoan diseases, such as leishmaniasis, are a cause of considerable morbidity throughout the world, affecting millions every year. In this study, two triterpenic acids (maslinic and oleanolic acids) were isolated from Tunisian olive leaf extracts and their in vitro activity against the promastigotes stage of Leishmania ( L .) infantum and Leishmania ( L .) amazonensis was investigated. Maslinic acid showed the highest activity with an IC 50 of 9.32 ± 1.654 and 12.460 ± 1.25 μg/ml against L. infantum and L. amazonensis , respectively. The mechanism of action of these drugs was investigated by detecting changes in the phosphatidylserine (PS) exposure, the plasma membrane permeability, the mitochondrial membrane potential and the ATP level production in the treated parasites. By using the fluorescent probe SYTOX® Green, both triterpenic acids showed that they produce a time-dependent plasma membrane permeabilization in the treated Leishmania species. In addition, spectrofluorimeteric data revealed the surface exposure of PS in promastigotes. Both molecules reduced the mitochondrial membrane potential and decreased the ATP levels to 15% in parasites treated with IC 90 for 24 h. We conclude that the triterpenic acids tested in this study, show potential as future therapeutic alternative against leishmaniasis. Further studies are needed to confirm this.

The essential oils of the dried aerial parts of Ruta chalepensis collected from the north of Tunisia were recovered by hydro-distillation with approximately 5.51% yield on a dry weight basis. The effects of drying and hydro-distillation duration on the chemical composition of the essential oils were studied. The obtained essential oils of the different parts of the herb were analyzed by GC–MS and 13 major compounds were identified. The main ones are 2-undecanone (77.18%), 2-decanone (8.96%) and 2-dodecanone (2.37%). 2-Undecanone was shown to be the unique component (100%) of the essential oil obtained from R. chalepensis flowers. Pulegone was identified only in the essential oil of the stems (about 32.11%) and camphor was identified exclusively in the essential oil of leaves (2.46%). The identification of the components of R. chalepensis essential oil should contribute to the understanding of the pharmacological activities of the herb.

Leishmaniasis is one of the neglected tropical diseases in terms of drug discovery and development. Furthermore, the chemotherapy used to treat this disease has been proved to be highly toxic and to present resistance issues. As consequent, the need for novel leishmanicidal molecules has notably increased in the recent years. In the present work an attempt was made to evaluate the antioxidant and leishmanicidal activities besides presence of compounds in leaf extracts of 5 different Tunisian olive tree varieties, used as traditional medicine in this country. The concentration of extracts needed to inhibit 50% of the parasitic growth (IC50) was estimated using different Leishmania strains. All tested extracts showed an inhibitory effect on the parasite growth with IC50 ranging from 2.130±0.023 to 71.570±4.324μg/ml, respectively for the methanolic extracts of Limouni and Zarrazi against Leishmania donovani. In fact, this activity was significantly affected by the olive cultivar and the tested Leishmania strain. Furthermore, the activities against both Leishmania tropica and major species were correlated to the total phenolic compounds. These results could suggest that olive leaf extract could carry potential new compounds for the development of novel drugs against Leishmaniasis.

The olive tree (Olea europaea, Oleaceae) has historically provided huge economic and nutritional benefits to the Mediterranean basin. In fact, olive leaf extracts have also been used by native people of this area in folk medicine to treat fever and other diseases such as malaria. Recently, several studies have focused on the extraction of high-added-value compounds from olive leaves. However, no previous studies have been developed in order to evaluate the activity of these extracts against Acanthamoeba. In the present work, olive leaf extracts from five different Tunisian varieties of olive trees (Chemlali Tataouine, Zarrazi, Toffehi, Dhokkar, and Limouni) were obtained by using three different solvents, and their activity against the trophozoite stage of Acanthamoeba castellanii Neff was screened. The IC50/96 h (50 % parasite growth inhibition) was chosen as the appropriate and comparable data to give as previously described. It could be observed that the amoebicidal activity was dose dependent. Trophozoite growth was inhibited by all the tested extracts with IC50 ranging from 8.234 ± 1.703 μg/ml for the alcoholic mixture of the Dhokkar extract to 33.661 ± 1.398 μg/ml for the methanolic extract of the Toffehi variety. The activity in fact was affected especially by the tested variety and not by the solvent extraction, the Dhokkar variety being the most active one as mentioned above.