Chemical composition and Antimicrobial Activity of the Algerian Laurus nobilis Essential oil

The aim of this research is to determine the chemical composition and the antimicrobial activity of Algerian Laurus nobilis essential oil. The chromatographic analyses (CG/MS) have shown that the major components of Laurus nobilis essential oil are the 1.8 cineol (24,658%) and the linalol (18,563%). The Laurus nobilis essential oil has shown an antimicrobial activity against all the tested strains except the Pseudomonas aeruginosa which shown a strong resistance. The Minimum Inhibitory Concentrations (MIC), Minimum Bactericidal Concentrations (MBC) and Minimum Fungicidal Concentrations (MFC) have been determined by the agar dilution method, some micro-organisms were susceptible to the essential oils that have the MBC values between 1% and 0.03%. A fungicidal action has been obtained regarding the Candida albicans, a fungistatic one regarding the Saccharomyces cerevisiae, these results promise to get a scientific validation to the massive use of this species

Biodiversity of Culicidae (Insecta: Diptera) in the Region of Khenchela (Northeast Algeria)

Mosquitoes are considered as vectors of serious human diseases. The prevention of parasitic and arboviral vector-borne diseases is based mostly on vector control strategies. This control cannot be effective unless a strong knowledge of mosquito biology and distribution in the working area. In this context, and in order to improve the knowledge on the specific diversity of the culicids fauna in the region of Khenchela (northeast of Algeria), an inventory of mosquitoes was carried out for the first time in this region. Larval collection was conducted in various types of habitats through continuous monitoring of seven sites from May 2020 to September 2021.Systematic study revealed the presence of 10 species belonging to 5 genera; including Culexpipiens (Linneaus, 1758), Culexterritans (Walker, 1856), Culextheileri (Theobald, 1903), Culexmodestus (Ficalbi, 1890), Culisetalongiareolata (Macquart, 1838), Culisetaannulata (Schrank, 1776), Aedesgeniculatus (Olivier, 1791), Aedesvexans (Meigen, 1830), Orthopodomyiapulcripalpis (Rondani, 1872) and Uranotaeniaunguiculata (Edwards, 1913). The species Cx. pipiens was the most abundant (44.26 %) followed by Cs. longiareolata (39.57 %). The variation of diversity in the different sites depends on the type of breeding habitat. Our findings provide very important information on biodiversity, distribution and the relationship between species abundance and ecological factors. Therefore, the results can be very useful for the design and implementation of effective control programs

Evaluation de l'effet anti-oxydant des extraits de l'espèce Saharo-Endemique (Myrtus nivellei Batt & Trab.) obtenus in situ et in vitro

Myrtus nivellei Batt & Trab. est une plante saharo-endémique, très réputée au sud algérien pour ses vertus thérapeutiques en médecine populaire. Cependant, ses usages restent, toutefois, exclusivement limités au savoir-faire ancestral. Ce travail apporte une première contribution à l'investigation du pouvoir anti-oxydant des extraits méthanoliques de cette espèce récoltée in situ ainsi que des cals multipliés in vitro. Les analyses spectrophotométriques effectuées ont montré que l'extrait méthanolique de la plante récoltée in situ s'est avéré plus riche en polyphenols par rapport à l'extrait des cals. Il a éventuellement exprimé un bon pouvoir de capture des radicaux libres avec une EC50=0,98 mg/ml, et un très bon pouvoir inhibiteur de la peroxydation de l'acide linoléique estimé à 74,01%, qui s'est avéré largement supérieur à celui exprimé par l'acide ascorbique (50,57%) utilisé comme contrôle positif. Néanmoins, les extraits méthanoliques préparés à partir des cals ont exprimé le meilleur pouvoir chélateur des ions Fe2+ estimé à 66,71%

Evaluation de l'effet anti-oxydant des extraits de l'espèce Saharo-Endemique (Myrtus nivellei Batt & Trab.) obtenus in situ et in vitro

Myrtus nivellei Batt & Trab. est une plante saharo-endémique, très réputée au sud algérien pour ses vertus thérapeutiques en médecine populaire. Cependant, ses usages restent, toutefois, exclusivement limités au savoir-faire ancestral. Ce travail apporte une première contribution à l'investigation du pouvoir anti-oxydant des extraits méthanoliques de cette espèce récoltée in situ ainsi que des cals multipliés in vitro. Les analyses spectrophotométriques effectuées ont montré que l'extrait méthanolique de la plante récoltée in situ s'est avéré plus riche en polyphenols par rapport à l'extrait des cals. Il a éventuellement exprimé un bon pouvoir de capture des radicaux libres avec une EC50=0,98 mg/ml, et un très bon pouvoir inhibiteur de la peroxydation de l'acide linoléique estimé à 74,01%, qui s'est avéré largement supérieur à celui exprimé par l'acide ascorbique (50,57%) utilisé comme contrôle positif. Néanmoins, les extraits méthanoliques préparés à partir des cals ont exprimé le meilleur pouvoir chélateur des ions Fe2+ estimé à 66,71%

Traditional use of <em>Matricaria pubescens </em>(Desf.) Schultz in two regions of southern Algeria and contribution to study the antioxidant activity

562-567Algerian flora holds a rich diversity of medicinal and endemic plants, many of which are used in Algerian traditional medicine and have the potential to provide pharmacologically active natural products. The present study focuses on a spontaneous species of the central and Septentrional Sahara, Matricaria pubescens (Desf.) Schultz. The ethnobotanical survey of 122 people, among herbalists, town&rsquo;s people and traditional healers took place in two towns; Tamenrasset and Bechar. Various informations were collected on the traditional use of the chamomile of the Sahara, its various vernacular names (Ouazouaza) and preparation methods, such as decoction (38.80 %). Similarly, it was proved that many diseases are treated by the use of Matricaria pubescens (Desf.) Schultz, such as joint disease (26.20 %), fever (17.50 %), cough (14.50 %), and asthma (11.70 %). Regarding the toxicity of the plant, the majority of respondents (96.70 %) reported the absence of side effects. The survey on the field was very profitable, therefore, the Sahara chamomile is a species to preserve and increase. The phytochemical screening revealed the presence of tannins, coumarins, flavonoids and saponins, the antioxidant power of infused is put out by the iron reduction method (FRAP) and it proved good comparing with ascorbic acid (vitamin C)

Essential Oil Composition and Antibacterial Activity of Pteridium aquilinum (L.) Kuhn

Introduction: The present work aims to study the chemical composition of Pteridium aquilinum (L.) Kuhn essential oil and its antibacterial activity against three important phytopathogenic Gram-negative bacteria: Erwinia amylovora, Pectobacterium carotovorum subsp. carotovorum, and Pseudomonas savastanoi pv. savastanoi. Methods: The chemical composition of P. aquilinum L. essential oil produced by hydrodistillation was determined by gas chromatography-mass spectrometry. The antibacterial activity was tested using disk diffusion method and by determination of minimum inhibitory concentration values. The major components were linalool (10.29%), carvacrol (8.15%), benzaldehyde (5.95%), 2-undecanone (5.32%), and cuminaldehyde (4.57%). Results: The essential oil tested revealed a powerful antibacterial effect against all tested strains, with inhibition zone diameters ranging from 32.0 ± 0.58 to 33.7 ± 0.88 mm. Discussion: P. aquilinum EO contained 32.86% of oxygenated monoterpenes, which are known for their very powerful antimicrobial activities. The minimum inhibitory concentration values showed that P. aquilinum essential oil has very strong activity against E. amylovora (0.625 μl/ml), followed by P. carotovorum subsp. carotovorum (2.50 μl/ml) and P. savastanoi pv. savastanoi (5.00 μl/ml). The results obtained could contribute to the development of new potential agents for the control of bacterial diseases