Sami Aifa

Cumin (Cuminum cyminum L.) from traditional uses to potential biomedical applications.

Cumin (Cuminum cyminum L.) is a small annual and herbaceous plant belonging to the Apiaceae family. It is a multipurpose plant species cultivated in the Middle East, India, China, and several Mediterranean countries, including Tunisia. Its fruit, known as cumin seed, is most widely used for culinary and medicinal purposes. It is generally used as a food additive, popular spice, and flavoring agent in many cuisines. Cumin has also been widely used in traditional medicine to treat a variety of diseases, including hypolipidemia, cancer, and diabetes. The literature presents ample evidence for the biological and biomedical activities of cumin, which have generally been ascribed to its content and action of its active constituents, such as terpens, phenols, and flavonoids. The present paper provides an overview of phytochemical profile, biological activities, and ethnomedical and pharmacological uses of Cumin.

Antibacterial properties and mode of action of new triaryl butene citrate compounds.

The aim of this study was to evaluate the antibacterial activity of newly synthesized triaryl butene analogues of tamoxifen. Several compounds were synthesized and converted to citrate salts to ensure greater solubility. Four compounds showed significant antibacterial activity at micromolar concentrations against Gram-positive and Gram-negative foodborne pathogens including Listeria monocytogenes, Listeria ivanovii, Enterococcus faecalis, Staphylococcus aureus and Escherichia coli. Two compounds at 50 μM, caused only 7.8 and 11% hemolysis. One of these as well as the remaining two caused high K(+) and Na(+) efflux from bacterial cells. Ultrastructural alterations were also visible using transmission electron microscopy, which revealed severe damage of the inner or outer membrane of E. coli. L. ivanovii showed swelling, corrugations and similar damage indicating a loss of cell-wall integrity. Organometallic compounds may offer interesting opportunities for the design of novel classes of antimicrobial compounds.

Effect of the amino chain length and the transformation into citric acid salts of aryl-diphenyl-butenes and ferrocenyl-diphenyl-butenes bearing two dimethylaminoalkyl chains on their antimicrobial activities

In a previous work we have demonstrated the antimicrobial activity of ferrocenyl or phenyl derivatives of diphenyl butene series. This finding has opened a new area of applications of organometallic compounds.In order to improve these activities, we have synthesized new organic and organometallic diaryl butene compounds with different lengths of their amino chains. These new compounds, and also their ammonium salts, were tested against man pathogenic microorganisms Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), Staphylococcus aureus (ATCC 6538) and Enterococcus hirae (ATCC 10541).It emerged from the tests that the Gram+ bacteria are more sensitive to the compounds than Gram-, and the compounds with 3 carbon amino chains have a better antimicrobial activity than the one having a chain of 2 or 4 carbons.The transformation of compounds to citrate salts was accompanied by a significant regression of antibacterial activity against Pseudomonas aeruginosa, for both organic and ferrocenic molecules. This resistance problem has been solved using hydrochlorides salts rather than citrates one.

Evaluation of biofilm-forming ability of bacterial strains isolated from the roof of an old house

The bacterial diversity associated with biofilm-forming ability was studied. Eighteen bacterial strains were isolated from a microbial film collected from the roof of an old house located in Sfax, Tunisia. The purity of these microorganisms was confirmed by microscopic observation after repeated streaking on a Tryptic Soy agar medium. Biofilm formation was estimated using preliminary tests including a motility test, microbial adhesion to solvents (MATS), and the Congo Red Agar method (CRA). Since these tests showed no significant result, microplate tests, such as crystal violet and resazurin assays, were used. The results obtained showed that strain S61 was able to form a biofilm within 24 h (OD570 = 4.87). The viability of the S61 biofilm with resazurin assessed with fluorescence measurement was about 1.5 × 103. The S61 strain was identified as Staphylococcus epidermidis. In the biofilm studied here, it was the most biofilm-forming bacterium and will be used as a bacterial model for studying anti-biofilm activity.

Efficacy of a novel ferrocenyl diaryl butene citrate compound as a biocide for preventing healthcare-associated infections

The antiseptic and disinfectant potential of a formulation containing the tamoxifen analogue 1,1-bis[4-(3-dimethylaminopropoxy)phenyl]-2-ferrocenyl-but-1-ene citrate was assessed according to European standards and pharmacopeia in comparison with a commercial antiseptic product containing hexamidine diisethionate, chlorhexidine digluconate and chlorocresol as active ingredients. The formulation met the phase 1 requirement of reducing by 5 cycles the counts of microorganisms frequently involved in healthcare-associated infections, namely Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538, Enterococcus hirae ATCC 10541 and Candida albicans ATCC 10231. It also killed a clinical isolate of Acinetobacter baumannii which is highly resistant to antibiotics and antiseptics. In phase 2/step 2 tests, it reduced the counts of E. coli ATCC 10536 by 4 log cycles within 60 seconds on hands (standard EN 1499). The novel formula is a potent biocide, and this demonstration could lead to the development of a new commercial antiseptic.