Emira Noumi

Bio: Emira Noumi is an academic researcher from University of Monastir. The author has contributed to research in topics: Medicine & Chemistry. The author has an hindex of 19, co-authored 44 publications receiving 1198 citations. Previous affiliations of Emira Noumi include Yahoo! & University of Valencia.

Biological activities of the essential oils and methanol extract of tow cultivated mint species (Mentha longifolia and Mentha pulegium) used in the Tunisian folkloric medicine.

Abstract: The composition of the essential oils and methanolic extracts of two cultivated mint species (M longifolia and M pulegium), as well as the in vitro antimicrobial and antioxidant activities of the essential oil and methanol extract of Mentha longifolia and Mentha pulegium were compared GC-MS analysis of the essential oil identified 41 compounds constituting 9666 and 9613% of the total oil from M longifolia and M pulegium, respectively The later oils were rich on pulegone (4715 and 6111%, respectively) Moreover, 1,8 cineole (1154%), menthone (107%), α-pinene (357%), α-terpineol (317%) and d-cadinene (353%) were only present in M longifolia oil, while isomenthone (1702%), and piperitone (263%), were characteristic of M pulegium oil Shoot extract of the two species showed significantly different contents in total polyphenols (891 and 3741 mg GAE/g DW), flavonoids (6393 and 3383 mg CE/g DW) and tannins (147 and 307 mg CE/g DW), respectively in M longifolia and M pulegium The essential oils showed strong antimicrobial activity against all 16 microorganisms tested, whereas the methanol extracts were inactive Moreover, the essential oils showed higher antioxidant activity than the methanolic extracts against the DPPH and superoxide radical scavenging In fact, antioxidant activities of the oils were the same for both M longifolia and M pulegium against DPPH (IC50 = 9 and 10 μg/ml, respectively) and 2-fold and 4-fold higher than shoot extracts (IC50 = 20 and 48 μg/ml, respectively) Moreover, both oils showed the same antioxidative abilities as compared to the positive control (butylated hydroxytoluene) In the same way, the capacity to inhibit superoxide anion was very significant for the two oils (01 μg/ml for M longifolia and 011 μg/ml for M pulegium)

Mentha spicata Essential Oil: Chemical Composition, Antioxidant and Antibacterial Activities against Planktonic and Biofilm Cultures of Vibrio spp. Strains

Abstract: Chemical composition, antioxidant and anti-Vibrio spp. activities of the essential oil isolated from the aerial parts of Mentha spicata L. (spearmint) are investigated in the present study. The effect of the essential oil on Vibrio spp. biofilm inhibition and eradication was tested using the XTT assay. A total of 63 chemical constituents were identified in spearmint oil using GC/MS, constituting 99.9% of the total identified compounds. The main components were carvone (40.8% ± 1.23%) and limonene (20.8% ± 1.12%). The antimicrobial activity against 30 Vibrio spp. strains (16 species) was evaluated by disc diffusion and microdilution assays. All microorganisms were strongly affected, indicating an appreciable antimicrobial potential of the oil. Moreover, the investigated oil exhibited high antioxidant potency, as assessed by four different tests in comparison with BHT. The ability of the oil, belonging to the carvone chemotype, to inhibit or reduce Vibrio spp. biofilm warrants further investigation to explore the use of natural products in antibiofilm adhesion and reinforce the possibility of its use in the pharmaceutical or food industry as a natural antibiotic and seafood preservative against Vibrio contamination.

Antifungal properties of Salvadora persica and Juglans regia L. extracts against oral Candida strains

Abstract: We report in this work, and for the first time, the potent antifungal activities of Salvadora persica and Juglans regia L. on different Candida species. Methanol, ethyl acetate, and diluted acetone extracts of S. persica (fresh and dry plant) and J. regia L. were screened for in vitro activity against some Candida species. These plants were selected due to their traditional use for the treatment of oral infections. Plant preparations were screened for antifungal activity using a standard agar disc diffusion assay. Following study of the antifungal activity of plant extracts, their minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values were determined using broth microdilution assay. Among S. persica and J. regia L. extracts, ethyl acetate J. regia L. extract had potent antifungal activity against all Candida strains. The MIC values of the J. regia L. against Candida strains ranged from 0.006 to 0.195 mg/ml. Two C. albicans strains showed a high MIC value (3.125 mg/ml). These results indicate that extracts can contain compounds with therapeutic potential against Candida strains and, hence, their possible use as therapeutic agents.

Effect of Essential Oils on Pathogenic Bacteria

Abstract: The increasing resistance of microorganisms to conventional chemicals and drugs is a serious and evident worldwide problem that has prompted research into the identification of new biocides with broad activity. Plants and their derivatives, such as essential oils, are often used in folk medicine. In nature, essential oils play an important role in the protection of plants. Essential oils contain a wide variety of secondary metabolites that are capable of inhibiting or slowing the growth of bacteria, yeasts and moulds. Essential oils and their components have activity against a variety of targets, particularly the membrane and cytoplasm, and in some cases, they completely change the morphology of the cells. This brief review describes the activity of essential oils against pathogenic bacteria.

An Overview of the Immunological Defenses in Fish Skin

Abstract: The vertebrate immune system is comprised of numerous distinct and interdependent components Every component has its own inherent protective value, and the final combination of them is likely to be related to an animal’s immunological history and evolutionary development Vertebrate immune system consists of both systemic and mucosal immune compartments, but it is the mucosal immune system which protects the body from the first encounter of pathogens According to anatomical location, the mucosa-associated lymphoid tissue, in teleost fish is subdivided into gut-, skin-, and gill-associated lymphoid tissue and most available studies focus on gut The purpose of this paper is to summarise the current knowledge of the immunological defences present in skin mucosa as a very important part of the fish immune system, serving as an anatomical and physiological barrier against external hazards Interest in defence mechanism of fish arises from a need to develop health management tools to support a growing finfish aquaculture industry, while at the same time addressing questions concerning origins and evolution of immunity in vertebrates Increased knowledge of fish mucosal immune system will facilitate the development of novel vaccination strategies in fish

Marine microplastic-associated biofilms - a review

Abstract: Environmental context Marine microbial communities, which play a crucial role in all biogeochemical processes in the oceans, could be affected by microplastic pollution. Research is necessary to understand the interactions between marine microbial communities and microplastics, and to explore the potential for microplastics to serve as transport systems for pathogenic microorganisms. Our review summarises first insights into these topics and discusses gaps in our current knowledge. Abstract The accumulation of plastic in the marine environment is a long-known issue, but the potential relevance of this pollution for the ocean has been recognised only recently. Within this context, microplastic fragments (<5mm) represent an emerging topic. Owing to their small size, they are readily ingested by marine wildlife and can accumulate in the food web, along with associated toxins and microorganisms colonising the plastic. We are starting to understand that plastic biofilms are diverse and are, comparably with non-plastic biofilms, driven by a complex network of influences, mainly spatial and seasonal factors, but also polymer type, texture and size of the substratum. Within this context, we should raise the question about the potential of plastic particles to serve as vectors for harmful microorganisms. The main focus of the review is the discussion of first insights and research gaps related to microplastic-associated microbial biofilm communities.