Novel N-acylsulfonamides: Synthesis, in silico prediction, molecular docking dynamic simulation, antimicrobial and anti-inflammatory activities.

Microbial resistance to drugs currently traded in the market is a serious problem in modern medicine. In this field of research, we synthesized a novel N-acylsulfonamides (NAS) derivatives starting from commercially available compounds; morpholine, isocyanate of chlorosulfonyl and alcohols. The in vitro antimicrobial potential of synthesized compounds was screened against 04 Gram-negative bacteria; Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, 02 Gram-positive bacteria: Streptococcus sp, Staphylococcus aureus and 07 yeasts and fungi: Candida albicans, Candida spp, Penicillum spp, Aspegillus sp, Aspergillus flavus, Fusarium sp, and Cladosporium spp. The results of inhibition growth were compared with standard antimicrobial drugs with the goal of exploring their potential antimicrobial activity. In addition, the anti-inflammatory activity of the synthesized compounds was determined in-vitro by protein denaturation method. The obtained bioactivity results were further validated by in silico DFT (Density Functional Theory), ADME (Absorption-Distribution-Métabolisation-Excrétion), molecular docking studies and molecular dynamics simulations.Communicated by Ramaswamy H. Sarma.

Prevalence of microbial nosocomial infections in the resuscitation unit of the University Hospital of Annaba-Algeria / Prévalence des infections nosocomiales d'origine microbienne au service de réanimation du Centre hospitalo-universitaire de Annaba (Algérie)

Nosocomial infections constitute a significant public health problem but are poorly controlled in our health structures, especially those associated with resuscitation care. The first objective of this study was to identify the different microbial strains present in different biological samples taken from patients staying in the resuscitation unit of the Annaba University Hospital Center. The second objective was to assess the antimicrobial sensitivity of isolated microbes from the patients' samples, to determine the risk factors, the most incriminated microbial agents in nosocomial infections. During the study period from January 2013 to December 2016, we collected 1,151 biological samples from 1,938 patients admitted to Resuscitation Medical Service. The samples were subjected to different microbiological analyses. Our results showed that over 59% of the collected samples were microbiologically positive. The identified species include Candida albicans (115 cases) and Candida.sp (81 cases). The Gram-negative bacterial strains found in the samples included Acinetobacter baumannii (108 cases), Klebssiella pneumoniae (99 cases) Pseudomonas aeruginosa (79 cases), and Escherichia coli (73 cases). Gram positive bacteria included Staphylococcus aureus (94 cases) and Enterococcus faecalis (53 cases). The antibiogram analyses showed significant antibiotic resistance reaching 93.75% for ampicillin, but sensitivity to colistin reaching 81.81%. Moreover, the fungal strains are represented by the genus albicans, showing a significant resistance to antifungals, reaching 80% with miconazole. Conclusion. The nosocomial infections in the medical unit were caused by the candida genus and multi-resistant bacteria to various antibiotics and antifungals. The most important factor associated with these infections was the use of medical devices.

Contexte: Les infections nosocomiales sont un grand problème de santé publique, encore méconnu et mal maîtrisé au sein des structures sanitaires. Objectif: Le but de notre étude était d'identifier les différentes souches microbiennes présentes dans les prélèvements obtenus de patients séjournant à l'unité de réanimation du Centre hospitalo-universitaire d'Annaba. Nous avons également évalué leurs sensibilités aux antimicrobiens, et pour déterminer les facteurs de risque, les agents infectieux les plus incriminés ainsi que la sensibilité aux traitements proposés afin de prévenir et/ou traiter les infections nosocomiales. Matériel et méthode: C'est une étude rétrospective de janvier 2013 à décembre 2016, analysant les différents prélèvements microbiologiques effectués au service de réanimation médicale d'Annaba-Algérie. Durant cette période d'étude, 1 151 prélèvements ont été effectués sur les 1 938 patients admis. Ces prélèvements ont été soumis à différentes analyses microbiologiques. Résultats: Les résultats montrent que plus de 59 % des prélèvements contenaient des microbes. En effet, nous avons identifié Candida albicans dans 115, et Candida sp. dans 81 prélèvements. Les bactéries Gram négatif incluent l'Acinetobacter baumannii dans 108, Klbessiella pneumoniae dans 99, Pseudomonas aeruginosa dans 79, et Escherichia coli dans 73 prélèvements. Pour les bactéries Gram positif, nous avons isolé Staphylococcus aureus dans 94, et Enterococcus faecalis dans 53 prélèvements. Les antibiogrammes montrent une importante résistance aux différents antibiotiques, avec une résistance 93,75 % pour l'ampicilline, et une sensibilité à la colistine de 81,81 %. Les souches fongiques représentées par le genre albicans affichent aussi une résistance aux antifongiques qui atteignent 80 % pour la miconazole. Conclusion: Les infections nosocomiales dans l'unité de réanimation médicale du Centre hospitalo-universitaire (CHU) d'Annaba sont dominées par le genre candida et des bactéries multi résistantes à différents antibiotiques et antifongiques. Le port d'un dispositif médical semble favoriser les infections nosocomiales.

Effect of Citrus aurantium L. Essential Oil on Streptococcus mutans Growth, Biofilm Formation and Virulent Genes Expression.

In an oral cavity, dental caries, periodontal disease, and endodontic lesions are caused by well-known bacterial and fungal pathogens. Essential oils (EOs) have demonstrated antimicrobial activity suggesting their use for oral hygiene. The goal of this study was to evaluate the interaction of bitter orange flower (Citrus aurantium L.) essential oil with cariogenic bacteria Streptococcus mutans and human gingival epithelial cells. After extraction, the chemical composition of the essential oil was analyzed by gas chromatography, and its antimicrobial activity was evaluated against the growth and the expression of virulent genes in S. mutans. Finally, the effects of this essential oil on human gingival epithelial cell adhesion and growth were assessed using cell adhesion and proliferation assays. We showed that the major constituents of the tested essential oil were limonene, linalool, and ß-ocimene. The essential oil reduced the growth of S. mutans, and decreased expression of comC, comD, comE, gtfB, gtfC, and gbpB genes. It should, however, be noted that essential oil at high concentration was toxic to gingival epithelial cells. Overall, this study suggests that C. aurantium L. essential oil could be used to prevent/control oral infections.

The Effects of Mentha × piperita Essential Oil on C. albicans Growth, Transition, Biofilm Formation, and the Expression of Secreted Aspartyl Proteinases Genes.

The rise in resistance and changes in the spectrum of Candida infections have generated enormous interest in developing new antifungal drugs using natural molecules such as plant essential oils (EOs). Antimicrobial activity against foodborne pathogenic and spoilage microorganisms has been reported for EOs. The goal of this study was to assess the effect of Mentha × piperita essential oil (EO) on C. albicans growth, transition (change from blastospore to hyphae forms), and biofilm formation as well as on the expression of certain virulent genes. We show that whole EO and its vapor attenuated the yeast's growth, compared to that in the control. The effect of the EO was comparable to that of amphotericin-B (AmB). The EO and its vapor significantly decreased the morphological changes of C. albicans, reduced biofilm formation, and disrupted mature C. albicans biofilms. The effect produced by whole EO on biofilm formation/disruption was notably comparable to that observed with AmB. Exposure of C. albicans to EO and its vapor downregulated the expression of various genes, such as secreted aspartyl proteinases (SAP 1, 2, 3, 9, 10) and hyphal wall protein 1 (HWP1). Altogether, these results provide new insight into the efficacy of Mentha × piperita EO against C. albicans and suggest the potential of Mentha × piperita EO for use as an antifungal therapy in multiple applications.