Search

The chemical composition and antimicrobial activity of propolis from a semi-arid region of Morocco were investigated. Fifteen compounds, including triterpenoids (1, 2, 7–12), macrocyclic diterpenes of ingol type (3–6) and aromatic derivatives (13–15), were isolated by various chromatographic methods. Their structures were elucidated by a combination of spectroscopic and chiroptical methods. Compounds 1 and 3 are new natural compounds, and 2, 4–6, and 9–11 are newly isolated from propolis. Moreover, the full nuclear magnetic resonance (NMR) assignments of three of the known compounds (2, 4 and 5) were reported for the first time. Most of the compounds tested, especially the diterpenes 3, 4, and 6, exhibited very good activity against different strains of bacteria and fungi. Compound 3 showed the strongest activity with minimum inhibitory concentrations (MICs) in the range of 4–64 µg/mL. The combination of isolated triterpenoids and ingol diterpenes was found to be characteristic for Euphorbia spp., and Euphorbia officinarum subsp. echinus could be suggested as a probable and new plant source of propolis. [ABSTRACT FROM AUTHOR]

Origanum genus is one of the most widely used herbs in folk medicine for its biological properties. The present investigation aims to characterize, for the first time, endemic Origanum grosii collected from the Taounate region, Morocco. This characterization was realized by determining the concentration of metals in different parts of the plant (flowers, leaves, and stems) by ICP-MS, and the results were studied statistically by Principal Component Analysis (PCA). Phytochemical screening with the dosage of polyphenols and flavonoids has been conducted. To know more about this species, antihyperglycemic tests have been performed to highlight the presence or absence of the antidiabetic effect for this plant. An Oral Glucose Tolerance Test (OGTT) has been performed on normal mice which were divided into two groups of six mice each. Group 1 (control group) was treated with distilled water, and group 2 was treated with an aqueous extract of O. grosii by gavage at 150 mg/kg. Digestive enzyme α-amylase inhibition assay has also been evaluated to study the inhibition effect of the studied extract using acarbose as a control. The results showed that the leaves exhibited a high concentration of trace elements (Ca, Mg, and K) and total absence of heavy metals, which were found in small quantities (Cr, Ni, and B) on the stems, and this makes the plant safe to use. On the other hand, tannins, flavonoids, triterpenes, and steroids were the major families strongly present in this species. The antidiabetic results showed that O. grosii have significantly reduced postprandial hyperglycemia after glucose loading in normal rats. It showed also that this species has a significant antihyperglycemic activity reflected by the inhibition of α-amylase. The one responsible for this property could be the synergy between the trace elements and the nature of the chemical families of O. grosii species, which can make this plant useful in the management of postprandial hyperglycemia. [ABSTRACT FROM AUTHOR]

Volatile components from fresh and air-dried leaves of Juniperus thurifera var. africana, J. phoenicea and J. oxycedrus (Cupressaceae) were isolated by direct water distillation (Clevenger-type apparatus) and analyzed using GC (FID) and GC/MS. The essential oils from leaves of J. thurifera var. africana were characterized by a high sabinene content (16.5-21.8%), γ-terpinene (9.3-11.5%), and α-pinene (7.6-9.1%). The major components for J. phoenicea were α-pinene (38.2-58%) and δ-3-carene (7.6%), while 13-epi-manoyl oxide (12.5-13.2%), (Z)-6-pentadecen-2-one (11.5-12.2%), and α-pinene (8.5-17.1%) were the major components found in the leaf oils of J. oxycedrus. The fresh leaves of J. thurifera var. africana contained 1.46% oil, while the yield was 1.14% from the dried leaves. The oil yields from the dried leaves of J. phoenicea and J. oxycedrus were 0.94% and 0.01%, respectively. Air-drying moderately effected the qualitative and quantitative composition of the oils. [ABSTRACT FROM AUTHOR]

• Carvacrol, E-caryophyllene and caryophyllene oxide are the major compounds of L.c. • L.c presented significant insecticidal activity against Ceratitis capitata. • Essential oil could be used as alternative environmentally bio-insecticide. The present investigation was aimed to assess the toxicity of Lavandula coronopifolia (Lamiaceae) essential oil (EO) against adult Mediterranean fruit fly. Ceratitis capitata (Wiedemann) (Diptera Tephritidae) is one of the most destructive fruit pests in Morocco. Essential oil was extracted from leaves of lavender (L. coronopifolia) by hydrodistillation and analyzed by GC and GC/MS. The main compound is carvacrol (48.9%) followed by E-caryophyllene (10.8%) and caryophyllene oxide (7.7%). The EO was examined in the laboratory for 7 days to assess their activity against Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) adults by ingestion toxicity. We also conducted oviposition bioassay in the laboratory, testing the oviposition deterrence of essential oils. The oil showed 75% mortality of adults at the concentration of 150 µl/g after 24 h of exposure. Great differences in insect mortality were observed depending on the sex of the insects, oil concentrations and exposure time. The ingestion toxicity potential of L. coronopifolia on adults was higher (LC 50 = 86.34 µl/g, LC 95 = 236.07 µl/g) and also, deterred significantly the oviposition by C. capitata , reducing the number of eggs laid by about 94% compared with the controls for the concentration of 55µl/g. Results suggested that L. coronopifolia EOs may have potential as a control agent against this major stored product insect. [ABSTRACT FROM AUTHOR]

An inductively coupled plasma mass spectrometry was developed to determine 20 mineral elements and heavy metals in leaves of Cupressus atlantica Gaussen, a traditional Moroccan medicinal herb from five environmentally different sites in N'Fis valley (High Atlas Mountains). The results showed in the leaves that Ca, K, P, Mg, Na and Fe were the most abundant of the elements in all samples of the studied locality. The concentrations of trace metals from the leaves of this plant were in the order Ca>K > P > Mg>Na>Fe. The results of the mineral composition were analysed by hierarchical cluster and principal component analysis that established three statistically significant clusters.

The aim of this study was to analyse the composition of the essential oil (EO) of Lavandula coronopifolia from Morocco and to evaluate its in vitro antibacterial activity against antibiotic-resistant bacteria isolated from clinical infections. The antimicrobial activity was assessed by a broth micro-well dilution method using multiresistant clinical isolates of 11 pathogenic bacteria: Klebsiella pneumoniae subsp. pneumoniae, Klebsiella ornithinolytica, Escherichia coli, Enterobacter cloacae, Enterobacter aerogenes, Providencia rettgeri, Citrobacter freundii, Hafnia alvei, Salmonella spp., Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus. The main compounds of the oil were carvacrol (48.9%), E-caryophyllene (10.8%) and caryophyllene oxide (7.7%). The oil showed activity against all tested strains with minimal inhibitory concentration (MIC) values ranging between 1% and 4%. For most of the strains, the MIC value was equivalent to the minimal bactericidal concentration value, indicating a clear bactericidal effect of L. coronopifolia EO.

Three essential oils from three samples: stems, leaves and inflorescences of Thymus maroccanus Ball, obtained by hydrodistillation, were analysed by gas chromatography and gas chromatography coupled to mass spectrometry. The oils of stems, leaves and inflorescences afforded 68, 49 and 51 constituents, respectively. Quantitative and qualitative differences have been found between the analysed parts. The most abundant components in the stems oil included carvacrol (60.8%), α-terpineol (4.7%) and p-cymene (2.4%), while carvacrol (33%), p-cymene (25.3%) and α-pinene (11.6%) were the main components in the leaves. In the inflorescences, carvacrol (84.9%) is the major component. Antibacterial activity of the T. maroccanus Ball leaves oil was tested against eight Gram-positive and Gram-negative bacteria by the disc diffusion method. The values of inhibition zones for bacterial strains, which were sensitive to the essential oil of T. maroccanus leaves, were in the range of 11-43 mm.

In order to valorise natural substances, concentrations of 20 mineral elements were evaluated in five species of Moroccan thyme. These species which belong to the Lamiaceae family are Thymus leptobotrys, Thymus broussonetii, Thymus maroccanus, Thymus pallidus and Thymus satureioïdes growing in different regions of central and southern Morocco. Samples of plants were subjected to digestion and heavy metals were determined by inductively coupled plasma mass spectrometry. The highest concentrations of calcium, iron, zinc, cobalt and chromium were registered in T. broussonetii, T. pallidus, T. leptobotrys, T. maroccanus and T. satureioïdes with respective values of 1991, 423, 73, 6 and 11 mg/kg. Furthermore, silicium and boron were analysed only for the species T. broussonetii and their respective concentrations were found to be 112 and 43 mg/kg. The ultra trace elements Si, B, Ni, Ni, As, Li, V and toxic elements Cd and Pb were also evaluated. The results were treated by the method of principal components analysis.

Salvia officinalis (Common sage, Culinary sage) is an aromatic plant that is frequently used as a spice in Mediterranean cookery and in the food industry and as a traditional medicine for the treatment of several infectious diseases. The essential oils were obtained by two different methods [hydrodistillation (HD) and microwave (Mw)] from the aerial part of S. officinalis L. growing wild in Ourika-Marrakech in Morocco. Ourika is a large zone of the Atlas Mountains which is considered as a large reserve of Flora, especially medicinal and aromatic plants. The obtained oils were analysed by gas chromatography and gas chromatography-mass spectrometry and compared with that of Tunisia. Thirty-six compounds were identified from the Mw-extracted oil which accounted for 97.32% of the total oil composition. However, 33 compounds obtained by HD representing 98.67%. The major components were trans-thujone (14.10% and 29.84%), 1,8-cineole (5.10% and 16.82%), camphor (4.99% and 9.14%), viridiflorol (16.42% and 9.92%), β-caryophyllene (19.83% and 5.20%) and α-humulene (13.54% and 4.02%). Antibacterial, allelopathic (% germination in lettuce seeds and inhibited root growth obtained after treatment with S. officinalis oils) and antioxidant (IC₅₀ values 22 mg/mL) activities were studied.