Preparation and characterization of carbopol/silver nanoparticles composites obtained by heating process for antimicrobial application

Properties such as absorption, structural and external aspect of Carbopol/silver nanoparticles composites, prepared in DMF by heating process up to 30, 60, 80, 100 and 120 °C, were investigated by UV-visible, FTIR and SEM-EDS analyses. Samples were named respectively D30 to D120, according to the temperature at which they were extracted. The results showed that instead of the appearance of silver aggregates observed by SEM microscopy, all the obtained materials present a single absorption band centred at 430 nm, attributed to the classical surface plasmon excitation of the silver nanoparticles. The presence of silver nanoparticles is also proved by the X-ray powder diffraction XRD patterns, which show the appearance of small peaks corresponding to the face centered cubic (f.c.c.) silver phase in the case of D100 and D120 samples. Additionally strong interactions between silver ions and carboxylic groups of Carbopol were identified by ATR-FTIR spectroscopy. The thermal properties of the carbopol are effectively enhanced by the presence of silver nanoparticles as evidenced by thermo-gravimetric analysis. Furthermore the water loss that generally occurs at 100 °C in acrylic acid polymer was completely avoided in these new materials since less than 2 % of weight loss is recorded up to 160 °C. Finally, the inhibiting activity of Carbopol/silver nanoparticles composites against staphylococcus Aureus micro-organisms was confirmed for all the obtained materials, suggesting their suitable uses as effective growth inhibitors of micro-organisms and making them appropriate for diverse antimicrobial control systems

MEDICINAL PLANTS IN floristic regions of EL HARROUCH AND AZZABA (SKIKDA-ALGERIA): PRODUCTION AND THERAPEUTIC EFFECTS

Our study on the production and the therapeutic effects of medicinal plants used by the local population of the two study areas of El Harrouch and Azzaba in the region of Skikda (Algeria), shows that the species are divided into 22 species and 14 families. The most used is the Lamiaceae family with the species Th. vulgaris with hight consumption. The study of botanical characters of International Union for the Protection of New Varieties of Plants (UPOV), agronomic (installation condition of culture) and biochemical (essential oil, total phenols and flavonoids) of this plant demonstrates their economic and therapeutic interest. According to the results, it was found that the installation of thyme culture is very important, and knowledge of installation conditions and botanical characteristics (as UPOV   recommendations), are very important for better adapt this beneficial culture through their therapeutic and commercial value at the Skikda region

Retrospective study of epidemiological, clinicopathological and biological profils of 62 colorectal cancers cases in Jijel provence (Algeria)

In Algeria, the CRC wing and become the first digestive cancer in both sexes,  outperforming stomach cancer. To enrich the Algerian cancer registries, we analyzed the profiles of patients with these cancers in Jijel Willaya. This was a retrospective and descriptive analysis of epidemiological, clinicopathological and biological profiles of 62 CRC cases. We found that the CRC represented the first type of digestive cancers in which the three quarters were colon cancers. The most affected age group was 60-70 years with a male predominance and an average age of 56.20 years. The bleeding and abdominal pain were the majority telltale signs. The combined chemotherapy has been standardized with all patients and the Lieberkühnien adenocarcinoma was the major histological form. The disease issue and the choice of therapy depended on the K-RAS gene mutations. Our results were often compatible with the available literature and may provide reliable and relevant data on this disease.Key words: Colorectal cancer; Epidemiology; Therapy; Adenocarcinoma; K-RAS gen

Chemotypification of Thymus munbyanus subsp. coloratus (Boiss. & Reut.) Greuter & Burdet (Lamiaceae) essential-oil

Thymus munbyanus subsp. coloratus (Boiss. & Reut.) Greuter & Burdet (Lamiaceae) is a small shrub endemic to Algeria and Morocco where it’s found in lawns, rockeries and mountainous regions. From a phytochemical point of view this taxon has never been characterized. In this work we have analyzed the chemical compositions of the essential oils obtained from inflorescences and vegetative parts of Thymus munbyanus subsp. coloratus from Algeria by GC/MS. A total of 109 volatile components were identified in the two samples (103 in stems and leaves, 102 in inflorescences) accounting for 98.4 – 98.7% of the total compositions. Overall, they showed similar chemical profiles. The two essential oils were dominated by oxygenated monoterpenes (68.2% in flowers and 59.4% in vegetative parts), followed by monoterpene hydrocarbons (12.1% and 24.4%, respectively), sesquiterpene hydrocarbons (11.0% and 8.5%, respectively) and oxygenated sesquiterpenes (6.7% and 4.9%, respectively). The major oil constituent was borneol accounting for 44.8% and 31.2% of flowers and aerial parts essential oils, respectively. A new chemotype, i.e. borneol-chemotype, was characterized for the first time in the species

Characterization of Polyphenols and Volatile Compounds from Understudied Algerian Pallenis spinosa by HS-SPME-GC-MS, NMR and HPLC-MSn Approaches

Pallenis spinosa (L.) Cass. is a widespread plant in the Mediterranean region. Traditionally, it is used as a medicinal species to treat several ailments, from inflammation to skin injuries. Although the phytochemical content of this plant has already been investigated, there is currently limited data on Algerian P. spinosa. In this work, we focused on volatile compounds and non-volatile secondary metabolites extracted using HS-SPME and methanol from the aerial parts of P. spinosa collected from Northeast Algeria. Volatile constituents were analyzed by GC-MS, while non-volatile compounds were analyzed by NMR and HPLC-MSn. In total, 48 volatile compounds were identified, including sesquiterpene hydrocarbons (65.8%), monoterpene hydrocarbons (16.9%), and oxygenated monoterpenes and sesquiterpenes (8.3% and 6.5%, respectively). β-Chamigrene (16.2%), α-selinene (12.8%), β-pinene (10.6%), and β-caryophyllene (9.2%) were assessed as the main constituents. Concerning non-volatile metabolites, 23 polyphenols were identified (7.26 mg/g DW), and phenolic acids were predominant (5.83 mg/g DW). Tricaffeoylhexaric acid (1.76 mg/g DW), tetracaffeoylhexaric acid (1.41 mg/g DW), 3,5-dicaffeoylquinic acid (1.04 mg/g DW), caffeoyl dihexoside (0.35 mg/g DW), and chlorogenic acid (0.29 mg/g DW) were the most abundant ones. Several known flavonoids, such as tricin and patuletin glycosides, kaempferol, and apigenin, were also identified, and myricetin hexoside was detected in P. spinosa for the first time. Overall, our work is the first to report an exhaustive characterization of volatile and non-volatile secondary metabolites from Algerian P. spinosa. The results represent a step forward in revealing the chemistry of this widespread plant species. Furthermore, they may contribute to rationalizing its traditional medicinal applications and preserve the biodiversity of Algerian flora

Supercritical CO2 extracts and essential oils from Teucrium polium L. growing in Algeria: chemical composition and antioxidant activity

In this work, we studied the essential oils (EOs) obtained by hydrodistillation and lipophilic fractions extrated by carbon dioxide supercritical fluid extraction (SFE-CO2) from Teucrium polium (Lamiaceae). EOs and SFE-CO2 extracts were analyzed by GC and GC-TOFMS. EOs showed qualitative differences compared with SFE-CO2 extracts, though in both products germacrene D was the most abundant component. Notably a new EO chemotype, characterzed by germacrene D, β-eudesmol, shyobunol, and δ-cadinene, was reported. EOs along with SFE-CO2 extracts, plant powder, and solid residue after SFE were evaluated for total phenolic content (TPC) and antioxdiant activity by DPPH, FRAP, and ORAC assays. The raw plant material was the most active, followed by the solid residue after SFE-CO2 extraction. On the other hand, EO and SFE-CO2 extracts displayed weak activity. These results showed that the antioxidant compounds of T. polium are of hydrophilic nature and are not extracted or retained in the plant material after SFE-CO2 extraction

Microstructural, Hyperfine, and Magnetic Properties of FeSiBCuNb Deposits

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