Promising Antileishmanial Activity of Micromeria nervosa Essential Oil: In Vitro and In Silico Studies.

The present study aimed to evaluate the leishmanicidal potential of the essential oil (EO) of Micromeria (M.) nervosa and to investigate its molecular mechanism of action by qPCR. Furthermore, in silicointeraction study of the major M. nervosa EO compounds with the enzyme cytochrome P450 sterol 14α-demethylase (CYP51) was also performed. M. nervosa EO was analyzed by gas chromatography-mass spectrometry (GC-MS). Results showed that α-pinene (26.44%), t-cadinol (26.27%), caryophyllene Oxide (7.73 ± 1.04%), and α-Cadinene (3.79 ± 0.12%) are the major compounds of M. nervosa EO. However, limited antioxidant activity was observed, as this EO was ineffective in neutralizing DPPH free radicals and in inhibiting ß-carotene bleaching. Interestingly, it displayed effective leishmanicidal potential against promastigote (IC50 of 6.79 and 5.25 µg/mL) and amastigote (IC50 of 8.04 and 7.32 µg/mL) forms of leishmania (L.) infantum and L. major, respectively. Molecular mechanism investigation showed that M. nervosa EO displayed potent inhibition on the thiol regulatory pathway. Furthermore, a docking study of the main components of the EO with cytochrome P450 sterol 14α-demethylase (CYP51) enzyme revealed that t-cadinol exhibited the best binding energy values (-7.5 kcal/mol), followed by α-cadinene (-7.3 kcal/mol) and caryophyllene oxide (-7 kcal/mol). These values were notably higher than that of the conventional drug fluconazole showing weaker binding energy (-6.9 kcal/mol). These results suggest that M. nervosa EO could serve as a potent and promising candidate for the development of alternative antileishmanial agent in the treatment of leishmaniasis.

Antioxidant, antibacterial and insecticidal activities of cypress (Cupressus sempervirens L.) essential oil.

The aerial parts of cypress (Cupressus sempervirens L.) of three collect regions (Bizerte, Ben-Arous and Nabeul) were reported for their essential oil (EO) compositions, antioxidant, antimicrobial and insecticidal activities. Results showed that the higher EO yields were observed in Bizerte and Ben Arous (0.56%), followed by Nabeul (0.49%). The EO composition showed the predominance of α-pinene with 36.72% in Bizerte, 30.22% in Nabeul and 30% in Ben-Arous. Cypress EO of Bizerte showed higher antiradical capacity (IC50 = 55 µg/mL) than Ben-Arous (IC50 = 97.50 µg/mL) and Nabeul (IC50 = 155 µg/mL). E. faecalis was the most sensitive strain to cypress EO of Bizerte with the largest inhibition zone (IZ = 65 mm). Regarding the insecticidal activity, cypress EO of Bizerte had the highest mortality of Tribolium castaneum with a lethal concentration of LC50 = 164.3 µL/L air after 24 h exposure.

Protective effect of grape seed extract and exercise training on tissues toxicities in doxorubicin-treated healthy rat.

OBJECTIVE: The aim of the present study was to investigate the effects of Grape seed extract (GSE) and exercise training on Doxorubicin (Doxo)-induced cardio, hepato and myo toxicities in healthy rats. METHODS: Thirty male Wistar rats were randomly divided into five groups and daily treated by intraperitoneal route during two months either with ethanol 10% (Control); Doxo (1.5 mg/kg); Doxo + exercise (1.5 mg/kg + swimming exercise for 30 min twice a week); Doxo + GSE (1.5 mg/kg + GSE 2.5 g/kg); Doxo + GSE + exercise (1.5 mg/kg + GSE 2.5 g/kg + swimming exercise for 30 min twice a week). At the end of the treatment, tissues were collected and processed for the determination of oxidative stress (OS), intracellular mediators, energy fuelling biomarkers, carbohydrate metabolism parameters and muscle histopathology. RESULTS: Doxo provoked OS characterised by an increased lipoperoxidation (LPO) and protein carbonylation and decreased antioxidant enzyme activities. Doxo also affected intracellular mediators, disturbed carbohydrate metabolism and energy fuelling in skeletal muscle as assessed by down-regulated Electron Transport Chain (ETC) complex activities leading in fine to altered skeletal muscle structure and function. CONCLUSION: Almost all Doxo-induced disturbances were partially corrected with GSE and exercise on their own and more efficiently with the combined treatment (GSE + exercise).

Antioxidant, antibacterial, and antileishmanial potential of Micromeria nervosa extracts and molecular mechanism of action of the bioactive compound.

AIMS: This study aimed to determine the antibacterial and antileishmanial potential of Micromeria nervosa extracts. The identification of the antileishmanial compound and the study of its molecular mechanism of action have also been undertaken. METHODS AND RESULTS: Ethanol extract showed high polyphenol content and diethyl ether extract exhibited high DPPH scavenging and low beta-carotene bleaching activity (IC50 = 13.04 ± 0.99 and 200.18 ± 3.32 µg mL-1, respectively). However, diethyl ether extract displayed high antibacterial activity against Gram-positive strains including methicillin-resistant Staphylococcus aureus (MIC = 31.25 µg mL-1), Staph. aureus ATCC6538 (MIC = 62.5 µg mL-1), and Listeria monocytogenes ATCC 19115 (MIC = 125 µg mL-1), as well as high antileishmanial activity against the promastigote forms of L. infantum and L. major (IC50 = 11.45 and 14.53 µg mL-1, respectively). The active compound was purified using bioassay-guided fractionation and thin layer chromatography, and identified as ursolic acid using high-performance liquid chromatography coupled with a photodiode array and mass spectrometry. The purified compound was strongly inhibitory against the promastigote and amastigote forms of L. infantum and L. major (IC50 = 5.87 and 6.95 µg mL-1 versus 9.56 and 10. 68 µg mL-1, respectively) without overt cytotoxicity against Raw 264.7 macrophage cells (SI = 13.53 and 11.43, respectively). The commercial compound (ursolic acid) showed similar activity against amastigotes and promastigotes forms of L. infantum and L. major. Moreover, its molecular mode of action against leishmaniasis seems to involve the expression of the ODC and SPS genes involved in thiol pathway. CONCLUSION: Extracts of M. nervosa can be considered as a potential alternative to antimicrobial and antileishmanial drugs.

Anti-Candida and Anti-Leishmanial Activities of Encapsulated Cinnamomum verum Essential Oil in Chitosan Nanoparticles.

Nanoencapsulation is widely considered as a highly effective strategy to enhance essential oils' (EO) stability by protecting them from oxidative deterioration and evaporation. The present study aims to optimize and characterize an efficient technique for encapsulating Cinnamomum (C.) verum essential oil into chitosan nanoparticles using response surface methodology (RSM). Moreover, the optimized C. verum EO nanoparticle was investigated for its antibacterial (against Gram-positive and Gram-negative bacteria), antifungal (against Candida albicans), and antiparasitic activity (against Leishmania parasites). Five parameters were investigated using a Plackett-Burman and Box-Behnken statistical design: the chitosan molecular weight, TPP concentration, C. verum EO/chitosan ratio, mixing method, and the duration of the reaction. Encapsulation efficiency and anti-candida activity were considered as responses. The antibacterial, anticandidal, and anti-leishmanial activities were also assessed using a standard micro-broth dilution assay and the cytotoxicity assay was assessed against the macrophage cell line RAW 264.7. The optimized nanoparticles were characterized using Fourier transform infrared spectroscopy, Zeta potential, and scanning electron microscopy. The study results indicated that under optimal conditions, the nanoencapsulation of C. verum EO into chitosan nanoparticles resulted in an encapsulation efficiency of 92.58%, with a regular distribution, a nanoparticle size of 480 ± 14.55 nm, and a favorable Zeta potential of 35.64 ± 1.37 mV. The optimized C. verum EO/chitosan nanoparticles showed strong antifungal activity against C. albicans pathogens (CMI = 125 µg mL-1), notable antibacterial activity against both Gram-positive and Gram-negative bacteria (ranging from 125 to 250 µg mL-1), high leishmanicidal potential against the promastigotes form of L. tropica and L. major (IC50 = 10.47 and 15.09 µg mL-1, respectively), and a four-fold cytotoxicity reduction compared to non-encapsulated essential oil. These results suggest that C. verum EO-loaded chitosan nanoparticles could be a promising delivery system for the treatment of cutaneous Candida albicans infections.

Datura stramonium Flowers as a Potential Natural Resource of Bioactive Molecules: Identification of Anti-Inflammatory Agents and Molecular Docking Analysis.

The present study investigated the antioxidant, antibacterial, antiviral and anti-inflammatory activities of different aerial parts (flowers, leaves and seeds) of Datura stramonium. The plant material was extracted with 80% methanol for about 24 h. The sensitivity to microorganisms analysis was performed by the microdilution technique. Antioxidant tests were performed by scavenging the DPPH and ABTS radicals, and by FRAP assay. Anti-inflammatory activity was evaluated through the inhibition of nitric oxide production in activated macrophage RAW 264.7 cells. Cell viability was assessed with an MTT assay. Results show that the flower extract revealed a powerful antimicrobial capacity against Gram-positive bacteria and strong antioxidant and anti-inflammatory activities. No significant cytotoxicity to activated macrophages was recorded. High resolution electrospray ionization mass spectrometry and nuclear magnetic resonance analysis identified two molecules with important anti-inflammatory effects: 12α-hydroxydaturametelin B and daturametelin B. Molecular docking analysis with both pro-inflammatory agents tumor necrosis factor alpha and interleukin-6 revealed that both compounds showed good binding features with the selected target proteins. Our results suggest that D. stramonium flower is a promising source of compounds with potential antioxidant, antibacterial, and anti-inflammatory activities. Isolated withanolide steroidal lactones from D. stramonium flower extract with promising anti-inflammatory activity have therapeutic potential against inflammatory disorders.

Synergistic combination of Cinnamomum verum and Syzygium aromaticum treatment for cutaneous leishmaniasis and investigation of their molecular mechanism of action.

Combination therapy at appropriately suitable doses presents a promising alternative to monotherapeutic drugs. In this study, Cinnamomum verum and Syzygium aromaticum essential oils and their major compounds have exhibited substantial leishmaniacidal potential against both promastigote and amastigote forms of Leishmania (L.) major. However, they displayed high cytotoxicity against Raw264.7 macrophage cells. Interestingly, when combined with each other or with amphotericin B, they demonstrated a synergistic effect (FIC<0.5) with low cytotoxicity. These combinations are able to modulate the production of nitric oxide (NO) by macrophages. Notably, the combination of S. aromaticum Essential oil with amphotericin B stimulates macrophage cells by increasing NO production to eliminate leishmanial parasites. Furthermore, investigation of the molecular mechanism of action of these synergistic combinations reveals potent inhibition of the sterol pathway through the inhibition of the CYP51 gene expression. The findings suggest that combination therapy may offer significant therapeutic benefits in both food and pharmaceutical fields.

Laurel essential oil: biological activities and application for semolina preservation against the red flour beetle Tribolium castaneum (Tenebrionidae).

The phytochemical composition of Laurus nobilis essential oil and their anticholinesterase, antioxidant, and insecticidal potential were studied. Also, the oil volatile fraction was compared in semolina at the beginning and after storage periods. For that, a headspace solid-phase-microextraction analysis (HS-SPME) coupled with gas chromatography and mass spectrometry was undertaken. Significant quantitative and qualitative differences of the oil volatile fraction were detected according to storage periods and occupation space ratios. Additionally, anti-acetylcholinesterase activity of L. nobilis oil against T. castaneum adults was evaluated. Results revealed that insecticide activity varied according to storage duration and occupation space. Besides, the oil acts on acetylcholine hydrolysis by inhibiting the activity of acetylcholinesterase. These results highlighted that L. nobilis essential oil may be recommended as an eco-friendly alternative for preserving semolina during storage.

Antibacterial and antibiofilm activity of Peganum harmala seed extract against multidrug-resistant Pseudomonas aeruginosa pathogenic isolates and molecular mechanism of action.

Biofilm formation of the opportunistic pathogen Pseudomonas (P). aeruginosa is one of the major global challenges to control nosocomial infections due to their high resistance to antimicrobials and host defense mechanisms. The present study aimed to assess the antibacterial and the antibiofilm activities of Peganum (P). harmala seed extract against multidrug-resistant P. aeruginosa isolates. Chemical identification of the active compound and determination of its molecular mechanism of action were also investigated. Results showed that P. harmala n-butanol "n-BuOH" extract exhibited antibacterial activity against multidrug-resistant P. aeruginosa isolates. This extract was even more active than conventional antibiotics cefazolin and vaamox when tested against three P. aeruginosa multidrug-resistant isolates. In addition, P. harmala n-BuOH extract exhibited potent bactericidal activity against PAO1 strain at MIC value corresponding to 500 µg/mL and attained 100% killing effect at 24 h of incubation. Furthermore, P. harmala n-BuOH extract showed an antibiofilm activity against P. aeruginosa PAO1 and exhibited 80.43% inhibition at sub-inhibitory concentration. The extract also eradicated 83.99% of the biofilm-forming bacteria. The active compound was identified by gas chromatography-mass spectrometry as an indole alkaloid harmaline. Transcriptomic analysis showed complete inhibition of the biofilm-related gene pilA when PAO1 cells were treated with harmaline. Our results revealed that P. harmala seed extract and its active compound harmaline could be considered as a candidate for a new treatment of multidrug-resistant P. aeruginosa pathogens-associated biofilm infections.

Preventive and healing effect of high dosing grape seed flour on CKD patients of various stages and aetiologies.

INTRODUCTION: Chronic kidney disease (CKD) is a worldwide public health concern characterised by a progressive alteration of renal function, and obesity, diabetes and hypertension are major risk factors. Oxidative stress is commonly observed in CKD patients resulting from an imbalance between overproduction of reactive oxygen species (ROS) and impairment of defense mechanisms. Therefore, strategies that alleviate oxidative stress may have major clinical implications towards improving vascular health and reducing the burden of CKD. Also, CKD worsens the quality of life of patients, therefore it is fundamental to implement new therapeutic strategies aimed at slowing down its progression. MATERIALS AND METHODS: This interventional study is a randomised placebo-controlled clinical trial consisting at the daily oral supplementation with high dosing grape seed flour (GSF ≈ 1 g/kg) for experimental (n = 30) or starch for placebo (n = 10) to patients suffering from CKD of various stages and aetiologies. Blood and urine samples were collected at baseline and after a six-month-long supplementation period to follow up the disease evolution through the determination of renal function biomarkers, as well as antioxidant, anti-inflammatory and blood parameters. RESULTS: Supplementation with high dosing GSF was safe and well tolerated during the entire period of investigation. GSF clearly improved the main renal function biomarkers as GFR, proteinuria, blood pressure, oxidative stress and inflammation as well as the overall patient welfare as indicated by several blood parameters. CONCLUSION: Most importantly high dosing GSF specifically halted and even reversed the progression of diabetic nephropathy a major cause of CKD and end stage renal disease.

Phenolic constitutents, antioxidant and repellent activities of coriander (Coriandrum sativum L.) fruits using different solvent extracts.

The organic solvent extracts (hexane, chloroform, acetone, methanol and water) of coriander fruits were reported for their antioxidant and repellent activities. The methanol and acetone extracts revealed the highest antiradical activity as compared to the other solvent extracts. HPLC analysis revealed that phenolic acids were the major compounds in chloroform and acetone extracts, whereas flavonoids in methanol and water extracts. The methanol extract of coriander fruits exhibited the highest repellent effect against coleopteran insects. Additionally, the hexane extract of coriander fruits also exhibited potent repellent and toxic activities against rice weevil. It appeared that coriander fruit extract obtained with the apolar solvent had more repellent potential against Sitophilus oryzae as compared to Tribolium castaneum. For Lasioderma serricorne, the methanol extract of coriander fruits reduced in a very significant way the adults followed by the chloroform and hexane extracts.

Streptomyces tunisiensis DSM 42037 mediated bioconversion of ferulic acid released from barley bran.

Streptomyces tunisiensis DSM 42037 exhibited growth capacity on a minimum medium containing 1% barley bran. This peculiar strain released 83.5% of total ferulic acid present in barley bran after 5 days of incubation and the highest amount of released ferulic acid (19 mg/L) was observed on the 3rd day of incubation. The concentrated supernatant of S. tunisiensis also released ferulic acid from the parietal arabinoxylan complex of barley bran. This strain was able to convert the free ferulic acid into 4-vinyl guaiacol (14 mg/L) and acetovanillone (12 mg/L) at molar yield of 97% and 83% respectively. The biotransformation products were successively purified by preparative thin layer and silica gel column chromatography followed by HPLC and identified by 1H nuclear magnetic resonance. Streptomyces tunisiensis DSM 42037 could have potential applications in the food, pharmaceutical and cosmetic industries thanks to its ability in biotransforming ferulic acid into 4-vinyl guaiacol and acetovanillone.

Vasomodulatory effects of semi-purified fractions of garlic aqueous extract on chick chorioallantoic membrane.

Allium sativum (As), commonly known as garlic, has been used for a long time, for its therapeutic effects. Recent studies showed the ability of As to modulate vascular activity. The present study aimed to investigate the vasomodulatory effects of aqueous extract of As and to analyse the molecular nature of the active components. Experiments were performed on chick chorioallantoic membrane. Fractions of garlic were directly injected using micropipette on a high vessel density area. Our results clearly indicated that garlic increased permeability and induced vasodilatation of blood vessels and capillaries. These effects were dose-dependent and had been observed just few minutes after the onset of treatment. The active component responsible of these effects, which had a low molecular weight seems to be of peptide nature and appeared different from Dially Sulfide (DAS) and Dially Disulfide (DADS).

Protective effect of (Xenical+GSF) against I/R-induced blood brain barrier disruption, ionic edema, lipid deregulation and neuroinflammation.

Ischemic stroke is a leading cause of mortality worldwide that occurs following the reduction or interruption of blood brain supply, characterized by a cascade of early events as oxidative stress and ensuing neuro-inflammation, energy failure and the burst of intracellular Ca++ resulting in activation of phospholipases and large increase in FFA including arachidonic acid, ultimately leading to nervous cell death. Grape Seed Flour (GSF) is a complex polyphenolic mixture harboring antioxidant, anti-inflammatory and neuroprotective properties. Orlistat (Xenical ™,Xe) is a gastro-intestinal lipase inhibitor and an anti-obesity agent. In an earlier study we reported the higher efficiency in neuroprotection against HFD-induced brain lipotoxicity when combining the two drugs (GSF + Xe). As a result repurposing Xe as an adjunct to GSF therapy against stroke appeared relevant and worthy of investigation. I/R insult disrupted the blood brain barrier (BBB) as assessed by EB dye extravasation, increased water and Na+ within the brain. Ultrastructurally I/R altered the brain blood capillaries at the vicinity of hippocampus dentate gyrus area as assessed by transmission and scanning electron microscopy. I/R altered lipid metabolism as revealed by LDL/HDL ratio, lipase activity, and FFA profiles. Moreover, I/R induced neuro-inflammation as assessed by down-regulation of anti-inflammatory CD 56 and up-regulation of pro-inflammatory CD 68 antigen. Importantly almost all I/R-induced disturbances were retrieved partially upon Xe or GSF on their own, and optimally when combining the two drugs. Xe per se is protective against I/R injury and the best neuroprotection was obtained when associating low dosage Xe with high dosage GSF, enabling neuroprevention and cell survival within hippocampus dentate gyrus area as revealed by increased staining of Ki 67 proliferation biomarker.

Identification of an antiviral compound isolated from Pistacia lentiscus.

This study screened mastic gum (Pistacia lentiscus L.) for antiviral activity against herpes simplex virus type 2 (HSV-2), coxsackievirus type B3, and adenovirus type 5. The organs of this plant (leaves, stem, and seed) were macerated sequentially using solvents of increasing polarity (hexane, dichloromethane, ethyl acetate, and methanol). Only the methanol extract of stem exhibited significant activity against HSV-2. This extract showed anti-HSV-2 activity with a selectivity index of 51 (50% cytotoxic concentration = 186 µg/mL; 50% inhibitory concentration = 3.63 µg/mL), and demonstrated direct inhibition against this virus with a virucidal selectivity index of 620 (50% virucidal concentration = 0.30 µg/mL). A bio-guided assay involving thin-layer chromatography led to the isolation of two active compounds, which have been identified as dammaradienone and dammaradienol using high-performance liquid chromatography-diode array detection coupled with electrospray ionization mass spectrometry. P. lentiscus has been widely studied for other biological activities. However, to our knowledge, this is the first report of P. lentiscus L. exhibiting antiviral activity.

Draft genome sequence of Streptomyces tunisialbus DSM 105760T.

Streptomyces strains are well known as promising source of bioactive secondary metabolites, important in ecology, biotechnology and medicine. In this study, we present the draft genome of the new type strain Streptomyces tunisialbus DSM 105760T (= JCM 32165T), a rhizospheric bacterium with antimicrobial activity. The genome is 6,880,753 bp in size (average GC content, 71.85%) and encodes 5802 protein-coding genes. Preliminary analysis with antiSMASH 5.1.2. reveals 34 predicted gene clusters for the synthesis of potential secondary metabolites, which was compared with those of Streptomyces varsoviensis NRRL ISP-5346.

Natural colourants analysis and biological activities. Association to molecular markers to explore the biodiversity of Opuntia species.

INTRODUCTION: Synthetic colourants are subject to various allergies. As a result, the use of plant-based additives has proved promising. OBJECTIVE: It is in this perspective that our objective was undertaken to investigate natural colourants from edible cactus. Opuntia species populations were single-sequence repeat (SSR) fingerprinted, the analysis of betalains and phenolic compounds and the evaluation of their biological potentials were also characterised. RESULTS: Photometric quantification of betalains and phenols showed an interspecific variation across Opuntia species. Opuntia ficus indica fruits showed the highest betalain [betaxanthins; 843.67 and betacyanins; 1400 mg/100 g dry weight (DW)] and polyphenol contents. Reversed-phase high-performance liquid chromatography (RP-HPLC) analysis showed that the variation of individual phenols profile was influenced by interspecific and genetic factors. Isorhamnetin-O-(di-deoxyhexosyl-hexoside) was the major compound and its content varied according to Opuntia species, while catechol was the predominant phenolic compound in O. humifusa with 1.88 µg/g DW. Concerning cactus species, Opuntia colourants exhibited a potent antiradical activity [half maximal inhibitory concentration (IC50 ) up to 1 µg/mL]. Opuntia species were effective against Gram-positive and Gram-negative bacterial strains [inhibition zone (IZ) up to 27 mm]. A high genetic diversity within Opuntia genotypes based on SSR markers was revealed. UPGMA (unweighted pair group method with arithmetic mean) dendrogram and PCoA (principal coordinate analysis) based on natural pigments and antimicrobial profiles indicated significant variation. The correlation approach proved the presence of a probably metabolic relationship between genetic markers, pigments and their biological activities. CONCLUSION: A possible association between molecular approach and metabolic profile analysis of Opuntia allows tracing the relationship among species for its genetic conservation.

Neuroprotective effect of grape seed extract on brain ischemia: a proteomic approach.

Stroke is one of the leading causes of long-lasting disability in human and oxidative stress an important underlying cause. Molecular insights into pathophysiology of ischemic stroke are still obscure, and the present study investigated the protective effect of high dosage Grape Seed Extract (GSE 2.5 g/kg) on brain ischemia-reperfusion (I/R) injury using a proteomic approach. Ischemia was realized by occlusion of the common carotid arteries for 30 min followed by 1 h reperfusion on control or GSE pre-treated rats, and a label-free quantification followed by mass spectrometry analysis used to evaluate I/R induced alterations in protein abundance and metabolic pathways as well as the protection afforded by GSE. I/R-induced whole brain ionogram dyshomeostasis, ultrastructural alterations, as well as inflammation into hippocampal dentate gyrus area, which were evaluated using ICP-OES, transmission electron microscopy and immuno-histochemistry respectively. I/R altered the whole brain proteome abundance among which 108 proteins were significantly modified (35 up and 73 down-regulated proteins). Eighty-four proteins were protected upon GSE treatment among which 27 were up and 57 down-regulated proteins, suggesting a potent protective effect of GSE close to 78%of the disturbed proteome. Furthermore, GSE efficiently prevented the brain from I/R-induced ion dyshomeostasis, ultrastructural alterations, inflammatory biomarkers as CD56 or CD68 and calcium burst within the hippocampus. To conclude, a potent protective effect of GSE on brain ischemia is evidenced and clinical trials using high dosage GSE should be envisaged on people at high risk for stroke.

Phytochemical investigation and biological activities of Echium arenarium (Guss) extracts.

The present work was developed to evaluate the in vitro antioxidant, antibacterial, antileishmanial and cytotoxic activities of Echium arenarium (Guss) extracts, and to analyze their phytochemical composition. The highest content of total phenolic compounds was obtained in the ethyl acetate extract which showed the best DPPH scavenging activity and ß-carotene bleaching inhibition (IC50 = 1.1 and 9.94 µg/mL respectively). It also exhibited the highest antibacterial activity against Gram-positive bacteria (L. monocytogenes; S. aureus; MRSA, E. faecalis and B. cereus) and antileishmanial activity against L. major (IC50 = 13.91 ±â€¯0.43 µg/mL) and L. infantum (IC50 = 9.91 ±â€¯0.15 µg/mL). Moreover, the active extract exhibited potent antiamastigote activity (IC50 = 22.48 ±â€¯0.14 µg/mL and 18.59 ±â€¯0.09 µg/mL against L. major and L. infantum respectively). Cytotoxicity studies revealed low toxicity against Raw 264.7 macrophage cell line (IC50 = 145.80 ±â€¯0.84 µg/mL, SI < 10). Luteolin-7-O-glucoside was identified as the major flavonoid component by RP-HPLC analysis. In conclusion, Echium arenarium (Guss) extract was characterized by a wide range of biological activities and could be used as a potential natural anti-infectious drug.

Anti HSV-2 activity of Peganum harmala (L.) and isolation of the active compound.

Genital herpes is a sexually transmitted disease caused by herpes simplex virus type 2 (HSV-2). Nucleoside analogues such as acyclovir (ACV) are the usual therapy for treating HSV infection. However, the overuse of this drug has led to the emergence of resistant strains. Therefore, the search for new alternative or complementary molecules to overcome this obstacle is needed. In this objective, Peganum harmala was investigated for its HSV-2 activity. The organic extracts of the different plant organs were evaluated for their cytotoxicity on Vero cells by the MTT test and anti HSV-2 activity by plaque reduction assay. Only the methanol seeds extract was active with a 50% inhibitory concentration (IC50) and a selectivity index (SI) of 161 and 13.2 µg/mL, respectively. In addition, the study of the antiviral mode of action revealed that this extract exerts a virucidal action both during the entry of viruses and the release of the newly formed virions, whereas no cell protection effect was observed. The active compound was isolated by bio-guided purification using thin layer chromatography (TLC) and identified by GC-MS and HPLC-DAD-ESI-MSn as harmine. The combination of harmine standard compound with ACV showed a combination index (CI) of 0.5 indicating that these two compounds have a synergic effect. This data suggests that harmine could be associated to ACV to improve the treatment of genital herpes essentially for the immunocompromised patients.