Activité Acaricide Des Huiles Essentielles Du Mentha Pulegium, Origanum Compactum Et Thymus Capitatus Sur L’acarien Phytophage Tetranychus Urticae Koch (Acari : Tetranychidae)

The use of botanical acaricides extracted from plants as an alternative to replace the chemical acaricides is an interesting and efficient option to control pests and ameliorate their toxic effects to humans and the environment. The aim of this work was to evaluate the contact toxicity of Pennyroyal mint (Mentha pulegium), oregano (Origanum compactum) and thyme (Thymus capitatus) essential oils against adults, larvae and eggs of two-spotted spider mite Tetranychus urticae Koch (Tetranychidae). The chemical composition of these three plant essential oils was also characterized. Laboratory tests were conducted to determine the acaricidal effect of plant essential oils at several doses in geometric progression. The consequences of treatments on mortality were measured in relationships with concentrations of essential oils. On the other hand, the major constituents of the three essential oils were identified by gas chromatography-mass spectrometer (GC-MS) techniques. GCMS analyses proved that the major compound present in the essential oils of thyme and oregano is carvacrol (55.59 and 55.28% respectively) while the main component of pennyroyal mint essential oil is pulegone (67,63%). Laboratory bioassay results indicated that essential oils of thyme and pennyroyal mint caused the most important acaricidal effects in comparison with the essential oil of oregano. At a concentration of 1%, thyme and pennyroyal eradicate all adults of the mite while oregano causes a mortality of 84.99%. On larvae, the mortality rate of thyme, pennyroyal and oregano is 97.7; 89.47 and 57.89% respectively. The results of the present study concluded that plant essential oils could be useful in promoting research aiming at the development of new agent for pest control from the plants with medicinal values

Mécanismes de Biosynthèse et de Régulation des Glucosinolates

Les glucosinolates des produits naturels riches en soufre qui, après hydrolyse par desthioglucosidases appelées myrosinases, produisent plusieurs produits différents (isothiocyanates, thiocyanates et nitriles), ces produits d'hydrolyse ont de nombreuses propriétés biologiques différentes, notament dans la défense des plantes contre les attaques des ennemis naturels. Nous résumons ici des études menées chez Brassica qui ont fourni des preuves moléculaires sur la biosynthèse des glucosinolates leurs régulations à différent niveaux et le contrôle génétique de la variation naturelle de leur accumulation. Glucosinolates are natural products sulfur-rich that upon hydrolysis by thioglucosidases called myrosinases produce several different products (isothiocyanates, thiocyanates, and nitriles), these hydrolysis products have many different biological properties, especially in the defense of plants against the attacks of natural enemies. Here we summarize studies in Brassica that have provided molecular evidence on the biosynthesis of glucosinolates, their regulation at different levels and the genetic control of the natural variation of their accumulation

Biosynthèse des glucosinolates indoliques et rôle écologique de leurs modifications secondaires

International audienc

Protein Kinase and HDAC Inhibitors from the Endophytic Fungus <i>Epicoccum nigrum</i>

A chemical investigation of the endophytic fungus <i>Epicoccum nigrum</i> isolated from leaves of <i>Mentha suaveolens</i> collected in Morocco resulted in the isolation of five new polyketides, epicocconigrones A and B (<b>1</b> and <b>2</b>), 3-methoxyepicoccone B (<b>3</b>), 3-methoxyepicoccone (<b>4</b>), and 2,3,4-trihydroxy-6-(methoxymethyl)-5-methylbenzaldehyde (<b>5</b>), together with five known compounds (<b>6</b>–<b>10</b>). The structures of the new compounds were unambiguously determined by extensive analysis of the 1D and 2D NMR and mass spectroscopic data. Compounds <b>1</b> and <b>10</b> showed potent inhibition of at least 15 protein kinases with IC₅₀ values ranging from 0.07 to 9.00 μM. Moreover, compounds <b>1</b> and <b>10</b> inhibited histone deacetylase (HDAC) activities with IC₅₀ values of 9.8 and 14.2 μM, respectively. A preliminary structure–activity relationship is discussed. Interestingly, compounds <b>1</b> and <b>10</b> exert mainly cytostatic effects in human lymphoma RAJI and U-937 cell lines

Prevalence and risk factors for latent tuberculosis infection among healthcare workers in Morocco.

Increased prevalence of latent tuberculosis infection (LTBI) has been observed among high-risk populations such as healthcare workers (HCWs). The results may depend on the method of LTBI assessment, interferon-gamma release assay (IGRA) and/or tuberculin skin test (TST). Here, we investigated the prevalence and risk factors for LTBI assessed by both IGRAs and TST in HCWs living in Morocco, a country with intermediate tuberculosis (TB) endemicity and high BCG vaccination coverage. HCWs were recruited in two Moroccan hospitals, Rabat and Meknes. All the participants underwent testing for LTBI by both IGRA (QuantiFERON-TB Gold In-Tube, QFT-GIT) and TST. Different combinations of IGRA and TST results defined the LTBI status. Risk factors associated with LTBI were investigated using a mixed-effect logistic regression model. The prevalence of LTBI among 631 HCWs (age range 18-60 years) varied from 40.7% (95%CI 36.9-44.5%) with QFT-GIT to 52% (95%CI 48.2-56.0%) with TST using a 10 mm cut-off. The highest agreement between QFT-GIT and TST (κ = 0.50; 95%CI 0.43-0.56) was observed with the 10 mm cut-off for a positive TST. For a definition of LTBI status using a double positive result for both QFT-GIT and TST, significant associations were found with the following risk factors: being male (OR = 2.21; 95%CI 1.40-3.49; p = 0.0007), belonging to age groups 35-44 years (OR = 2.43; 95%CI 1.45-4.06; p = 0.0007) and even more 45-60 years (OR = 4.81; 95%CI 2.72-8.52; p = 7.10-8), having a family history of TB (OR = 6.62; 95%CI 2.59-16.94; p = 8.10-5), and working at a pulmonology unit (OR = 3.64; 95%CI 1.44-9.23; p = 0.006). Smoking was associated with LTBI status when defined by a positive QFT-GIT result (OR = 1.89; 95%CI 1.12-3.21; p = 0.02). A high prevalence of LTBI was observed among HCWs in two Moroccan hospitals. Male gender, increased age, family history of TB, and working at a pulmonology unit were consistent risk factors associated with LTBI

Morocco’s First Biobank: Establishment, Ethical Issues, Biomedical Research Opportunities, and Challenges

Background. Biobanks are highly organized infrastructures that allow the storage of human biological specimens associated with donors’ personal and clinical data. These infrastructures play a key role in the development of translational medical research. In this context, we launched, in November 2015, the first biobank in Morocco (BRO Biobank) in order to promote biomedical research and provide opportunities to include Moroccan and North African ethnic groups in international biomedical studies. Here, we present the setup and the sample characteristics of BRO Biobank. Methods. Patients were recruited at several departments of two major health-care centers in the city of Oujda. Healthy donors were enrolled during blood donation campaigns all over Eastern Morocco. From each participant, personal, clinical, and biomedical data were collected, and several biospecimens were stored. Standard operating procedures have been established in accordance with international guidelines on human biobanks. Results. Between November 2015 and July 2020, 2446 participants were recruited into the BRO Biobank, of whom 2013 were healthy donors, and 433 were patients. For healthy donors, the median age was 35 years with a range between 18 and 65 years and the consanguinity rate was 28.96%. For patients, the median age was 11 years with a range between 1 day and 83 years. Among these patients, 55% had rare diseases (hemoglobinopathies, intellectual disabilities, disorders of sex differentiation, myopathies, etc.), 13% had lung cancer, 4% suffered from hematological neoplasms, 3% were from the kidney transplantation project, and 25% had unknown diagnoses. The BRO Biobank has collected 5092 biospecimens, including blood, white blood cells, plasma, serum, urine, frozen tissue, FFPE tissue, and nucleic acids. A sample quality control has been implemented and suggested that samples of the BRO Biobank are of high quality and therefore suitable for high-throughput nucleic acid analysis. Conclusions. The BRO Biobank is the largest sample collection in Morocco, and it is ready to provide samples to national and international research projects. Therefore, the BRO Biobank is a valuable resource for advancing translational medical research