Distribution modeling, soil properties, and variation in essential oils chemical composition of Rhanterium adpressum Coss. & Dur.

Modeling the distribution of Rhanterium adpressum, an endemic species from southwestern Algeria, and the interactions of soil’s chemical properties with the variability of chemical composition of its essential oils makes the objective of this study. Obtained MaxEnt model (AUC = 0.98) showed that the general distribution of genus Rhanterium established mainly by the contribution of eight bioclimatic variables derived from temperature and precipitation (90.5%). Projection of the model in future conditions until 2070 reveals that the habitats of this species will be very affected by climate changes. The analysis of 9 soil samples shows a sandy (77–96%), alkaline, and calcareous character with an electrical conductivity between 0.2 and 1.8 dS/m at 20°C. The chemical composition of terpenoids families during a period of 5 months was dominated by monoterpene hydrocarbons (70–90%) followed by oxygen monoterpenes (4.5–9.2%), hydrocarbon sesquiterpenes (1.6–9.9%), and oxygenated sesquiterpenes (4.3–7.2%). The variation of this composition in relation with phenological cycle and physicochemical properties of the soil was discussed

Characterization of a single clonal lineage of Fusarium oxysporum f. sp. albedinis causing Bayoud disease of date palm in Morocco

Bayoud, the #Fusarium wilt of date palm, was first detectd in southern Morocco (Draa Valley), after which it spread to most of the Moroccan pal groves. To assess whether the epidemic results from the spread of a single virulent clone, 42 isolats of #Fusarium oxysporum f. sp. #albedinis were collected from several cultivars of wilted palms at different locations in Morocco ; two isolates were included from Algeria, where the disease also occurs. The isolates were tested for vegetative compatibility group (VCG), restriction fragment length polymorphism (RFLP), and random amplified polymorphic DNA (RAPD). No polymorphism was observed either in RFLP studies on mitochondrial DNA or in RAPD analysis, and all strains belonged to a single VCG (0170). Sequences homologous to the DNA transposable element Fot1 were found in the genome of the #F. oxysporum f. sp. #albedinis$strains. Repetitive DNA patterns were produced when EcoRI-digested DNA of the isolates was probed with Fot1 ; 23 distinct hybridization patterns were established among the 44 isolates. Of these patterns, 4 accounted for more than 50$ f. sp. #albedinis strains at a genetic distance of 0.11. Such close genetic relationships between the isolates provides evidence that Moroccan #F. oxysporum f. sp. #albedinis$ populations may belong to a single clonal lineage that originated in Moroccan palm groves and eventually reached the Algerian oases. (Résumé d'auteur

Studying the electron flow formation in magnetron guns with a secondary emission metallic cathode

Presented are the results of studies concerning the multybeams systems and considering the possibility to increase the output current amplitudes by changing the geometrical dimensions of guns

ANTIMYCOBACTERIAL, ANTIOXIDANT AND CYTOTOXIC ACTIVITIES OF ESSENTIAL OIL OF GALL OF PISTACIA ATLANTICA DESF. FROM ALGERIA

Background: The aim of this study was to assess the antimycobacterial, antioxidant and the cytotoxic activities of the essential oil from the gall part of Pistacia atlantica Desf from Algeria. Materials and Methods: The antimycobacterial activity was evaluated by the broth microdilution method against three species of mycobacteria: Mycobacterium smegmatis, Mycobacterium aurum and Mycobacterium fortuitum. Antioxidant activity was determined using free-radical scavenging assays. The safety of essential oil was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on C3A and Vero monkey kidney cells. Results: The minimal inhibitory concentration (MIC) values ranged from 0.16 to 2.5 mg/mL with minimal bactericidal concentration (MBC) values ranged from 0.62 to >2.5 mg/mL. The antioxidant activity showed IC50 values ranged between 417.61 - >2000µg/mL and 495.6 - >2000µg/mL for DPPH and ABTS assay respectively. The cytotoxicity assay showed LC50 ranged between 26.47 to 93.64 µg/mL against Vero cells and 74.29 to 225.40 µg/mL against C3A. The results of this study show that the essential oils from the gall of P. atlantica have low toxicity and moderate activity against fast growing M. smegmatis and M. aurum. Conclusion: These results substantiate their potential as used in the treatment of non-tuberculous mycobacterial infections. This finding is predictive of their activity against M. tuberculosis, therefore, further study might be considered to investigate the activity against pathogenic Mycobacterium strains

Algerian Inuleae tribe species distribution modeling underinfluence of current and future climate conditions

This study aims to predict the impact of bioclimatic variables in current and future climatic scenarios on the distribution of Inuleae tribe species. Modeling the distribution of 30 species of the Inuleae tribe in Algeria was carried out with a maximum entropy model. Two models with 99 occurrence points were obtained with mean values of Area Under a Curve (AUC) of 0.987±0.01 and 0.971±0.02, reflecting excellent predictive power. Three bioclimatic variables contributed mainly to the first model and four - to the second one with cumulative contributions of 83.8% and 79%, respectively elucidating differences between species of the two major climatic zones in Algeria: the Tell and the Sahara. Two-dimensional niches of Algerian Inuleae species allowed to distinguish these two groups with the distribution of 18 Tell species, characterized by high rainfall (14-18°C, 400-1000 mm) and the other 12 species – distributed in hot and dry environments (17-24°C, 20-200 mm). Modeling the distribution under future conditions showed that habitats of the Saharan region would be much less suitable for these species with a variation in the annual mean temperature increase up to 20% and a decrease in annual precipitation, which could raise to 11 and 15%

Synergistic effects of essential oils and phenolic extracts on antimicrobial activities using blends of Artemisia campestris, Artemisia herba alba, and Citrus aurantium

This study explores the synergistic antibacterial effects of essential oils (EOs) and phenolic extracts from three plants against foodborne pathogenic bacteria. The present work aimed to investigate the synergistic effects of the binary and the ternary combinations of extracts using different blend proportions of the following plant extracts: Artemisia campestris (AC), Artemisia herba alba (AHA), and Citrus aurantium (CA). The antimicrobial activities of EOs and phenolic extracts were determined and evaluated against five strains. For the EOs, the results of the DIZ showed the existence of synergism for different combinations of binary blends, such as AC/AHA or AHA/CA against Escherichia coli, and AC/CA against Enterobacter faecalis. In addition, ternary blends of AC:AHA:CA at a ratio of 1/6:2/3:1/6 exhibited a synergy effect, as measured by the CI, against E. coli. On the other hand, for the phenolic extracts, synergistic effects were noticed for binary blends of AC/CA at different ratios against E. coli, E. faecalis, and Pseudomonas aeruginosa strains. Similarly, ternary blends of phenolic extracts presented synergy against E. coli, E. faecalis, P. aeruginosa strains, and even C. albicans. In this case, the blending ratios were crucial determining factors for maximizing the synergy effect. The study established that the proportion of a single drug could play an essential role in determining the bioefficacy of a drug combination treatment. Therefore, the results showed the importance of studying the modulation of antibacterial activities based on the proportions of extracts in the mixture and finding the range of proportions (as determined by SLMD) that have a synergistic/additive/antagonistic effect with no or low side effects, which can be used in a food preservation system

Send Orders for Reprints to [email protected] Chemical Composition, Antioxidant and Antimicrobial Activities of the Essential Oils of Three Algerian Lamiaceae Species

International audienceBackground: The present work investigates the chemical composition, the antioxidant and the antimicrobial activities of the Essential Oils (EOs) of three species of the Lamiaceae family gowning in Algeria: Thymus vulgaris L., Thymus algeriensis Boiss. & Reut. and Mentha pulegium L. Methods: Essential Oils (EOs) obtained by hydrodistillation of the aerial parts of the studied plants were analyzed by GC and GC-MS. The antioxidant activity of the EOs was determined using two different assays: free radical scavenging activity of DPPH • (2,2-diphenyl-1-picrylhydrazyl) and Phosphomolybdenum reducing power. The EOs were also tested for their antibacterial and antifungal activities against eight pathogenic bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, Bacillus cereus, Staphylococcus aureus, Methicillin resistant strain of S. aureus " MRSA " and Enterococcus faecalis); a yeast (Candida albicans); and a fungi (Fusarium oxysporum)

Chemical Composition, Antioxidant and Antimicrobial Activities of the Essential Oils of Three Algerian Lamiaceae Species

International audienceCITATIONS 0 READS 240 5 authors, including: Some of the authors of this publication are also working on these related projects: lipase inhibition: obesity treatment View project how the different properties structural influence in chelation of iron as dipole moment or lipophilicity View project Nadhir Gourine Université Amar Telidji Laghouat Abstract: Background: The present work investigates the chemical composition, the antioxidant and the antimicrobial activities of the Essential Oils (EOs) of three species of the Lamiaceae family gowning in Algeria: Thymus vulgaris L., Thymus algeriensis Boiss. & Reut. and Mentha pulegium L. Methods: Essential Oils (EOs) obtained by hydrodistillation of the aerial parts of the studied plants were analyzed by GC and GC-MS. The antioxidant activity of the EOs was determined using two different assays: free radical scavenging activity of DPPH • (2,2-diphenyl-1-picrylhydrazyl) and Phosphomolybdenum reducing power. The EOs were also tested for their antibacterial and antifungal activities against eight pathogenic bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, Bacillus cereus, Staphylococcus aureus, Methicillin resistant strain of S. aureus " MRSA " and Enterococcus faecalis); a yeast (Candida albicans); and a fungi (Fusarium oxysporum)

Synergistic antinociceptive activity of combined aqueous extracts of <i>Artemisia campestris</i> and <i>Artemisia herba</i>-<i>alba</i> in several acute pain models

<p>In this study, total phenolic and flavonoid contents, acute toxicity and the antinociceptive activity of <i>Artemisia campestris</i> and <i>Artemisia herba</i>-<i>alba</i>, individually and in combination, were investigated using multiple forms of pain in animals. Our results have been shown that plants are relatively safe without clinical signs of toxicity in animals. Thus, extracts were presented high levels in phenolic and flavonoid contents. <i>Artemisia</i> decoctions with 100, 200, 400 mg/kg b-w studied dose, clearly attenuate chemical and thermal noxious stimuli in writhing, formalin and hot-plate tests, and significantly reduced paw oedema in formalin test. Additionally, binary combination forms exhibited a great improvement in intensity and amplitude of antinociceptive activity in comparison with both plants used individually by a relative interference with opioid system. Our findings suggested the central and peripheral analgesic properties and confirmed the folkloric medicinal use of these plants in pain symptom treatment.</p