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Today, the number of antimicrobials used in treatment has decreased, especially due to drug resistance. We need new antimicrobials. Biofilms are an important cause of antimicrobial resistance. In this study, the antimicrobial and antibiofilm properties of the salt and silver complex of benzimidazolium-based NHC compound, which were previously synthesized and characterized, were evaluated. The antimicrobial properties were tested using the broth microdilution method, while their antibiofilm potential was determined by microtiter plate assay. Salt of the NHC compound (1a) showed antimicrobial activity on microorganisms at concentrations between 31.25-125 µg/mL. The silver complex (2a) of the NHC compound showed higher antimicrobial and antibiofilm activity than the salt compound. This activity was highest on Candida albicans yeast (MIC 3.9 µg/mL). Compound 2a reduced the biofilm structure of C. albicans yeast by 86.1% compared to the control. In addition, compound 2a showed 76.4-80.6% antibiofilm activity on gram-negative bacteria. NHC compounds are seen as a promising resource for the development of new generation antimicrobials. The NHC compound evaluated in this study was found to have significant antimicrobial and antibiofilm activity. These compounds could be an important resource for the discovery of future biofilm-acting antimicrobials.

Candida species are commonly encountered strains associated with a wide range of infections. Unlike bacterial pathogens, fungal pathogens treatment is difficult and the development of resistance has been increasing at an alarming rate. In this study, the antifungal and antibiofilm effect of thyme oil, rosemary oil, mint oil, citronella oil, was tested on Candida albicans, Candida tropicalis, Candida kefyr, Candida glabrata, Candida parapsilosis isolated from clinical samples. The agar disc diffusion method was employed to determine the antifungal effect of the essential oils, and the inhibition of biofilm formation was assessed using microtiter biofilm inhibition assay. The results indicated that all the essential oils inhibited Candida strains and their biofilm in varying degrees. The highest antifungal activity in all isolates was observed in the thyme oil (>50mm), while rosemary oil showed the highest antibiofilm effect (>77%) in all tested strains. These findings led us to assume that the active components found in essential oils might be potential antifungal agents, adding to the repertoire of therapeutic options for the treatment of candidiasis.

Rosemary officinalis L., Pelargonium graveolens L., and Mentha piperita L., essential oils are used by complementary medicine specialists simultaneously with traditional antibiotics for treatment purposes. The chemical composition of essential oils was analyzed by the gas chromatography-mass spectrometry method. In vitro antibacterial and antibiofilm activities of the essential oils were tested against extreme drug-resistant (XDR) colistinresistant and colistin susceptible Acinetobacter baumannii clinical strains. The synergistic activities between essential oils and colistin antibiotics were investigated by the checkerboard method. The highest antibacterial effect was detected in mint essential oil (2.5–5 μl/ml), followed by pelargonium essential oil (5–20 μl/ml) and rosemary essential oil (5–20 μl/ml). The combination of rosemary essential oil or pelargonium essential oil with colistin showed strong synergistic activity in most of the bacterial strains tested (fractional inhibitory concentration index ≤ 0.5; synergy). As a result of the combination of mint essential oil and colistin, an indifferent effect was observed in only two bacterial strains, and other strains could not be evaluated. No antagonistic effects were observed in any of the tested essential oils. As a result of the effectiveness of the combination, the minimum inhibitory concentration (MIC) values of colistin in XDR-A. baumannii clinical isolates decreased 2–32 fold. Additionally, the sub-MIC concentration of essential oils exhibited an inhibitory effect (48–90%) against the biofilm layer of tested A. baumannii strains.

Purpose: To investigate the antimicrobial, antibiofilm, and cytotoxicity properties of methallyl substituted benzimidazolium-based, silver-bound N-heterocyclic carbene (Ag(I)-NHC) complexes, with respect to their potential to act as antimicrobial agents.Methods: The antimicrobial, antibiofilm, and cytotoxicity properties of the four complexes, the synthesis and characterization of which were carried out previously, were investigated. The antimicrobial properties were tested using the broth microdilution method, while their antibiofilm potential were determined by microtiter plate assay. The L-929 cell line was used for cytotoxic studies.Results: Strong antibiofilm and antimicrobial effects were produced by Ag(I)-NHC complexes. Compounds 2 and 3 showed potent activities against E. coli strain, with effects similar to that of positive control antibiotic, while compounds 1 and 4 exhibited antimicrobial activity at a concentration of 31.2 μg/mL. The compounds were effective against biofilms formed at concentrations in the range of 32 – 84 %, and degraded mature biofilms at a concentration range of 14 - 66 %. Compounds 1 and 2 did not significantly affect cell survival (p > 0.05), while compounds 3 and 4 significantly reduced cell survival, when compared with untreated cells in the control group (p < 0.001).Conclusion: This study may be one of the few studies on benzimidazolium-derived NHCs. The compounds which produced antimicrobial, antibiofilm, and cytotoxic properties in this study may be valuable and novel antimicrobial agents. Therefore, there is need for further in vivo and in vitro studies on these compounds.

Objectives: Viral gastroenteritis is a major health problem that is common worldwide, especially in developing countries, and is responsible for the majority of childhood diarrhea disease. The aim of this study was to deter-mine prevalence of rotavirus and enteric adenovirus frequency and the age and seasonal distribution of viral agents in children with acute gastroenteritis attending to our hospital.Materials and Methods: In this study, 6999 stool specimens were investigated for the presence of rotavirus and adenovirus. The samples were obtained between January 2013 and August 2019 from children age 0-17 suffe-ring from acute gastroenteritis attending to our hospital. Frequency of rotavirus and adenovirus were retrospec-tively evaluated with regard to seasonal distribution, gender and age of patients.Results: Viral antigens were detected in 1341 (19.1 %) of the specimens examined in the study. Among the posi-tive results, rotaviruses and adenoviruses frequency were detected in 14.7 %, 4.4 %respectively. Rota-adenovirus co-infection was 8.4 %(n=113). Whereas rotavirus antigen was determined in all age groups, the highest was found in children age 0-2 with a rate of 57.9 %. Moreover, considering the seasonal distribution of the cases, it can be said that rotavirus infections are mostly observed in winter and spring, while adenovirus infections are frequently detected in summer and autumn. Conclusion: Rotavirus and enteric adenovirus infections are important public health problems that caused hos-pitalization, morbidity and mortality among children, Amaç: Viral gastroenteritler, başta gelişmekte olan ülkelerde olmak üzere tüm dünyada yaygın olarak görülen, özellikle çocukluk çağı ishallerinin büyük bir kısmından sorumlu olan önemli bir sağlık sorunudur. Çalışmamızda, hastanemize başvuran akut gastroenteritli çocuklarda, rotavirüs ile enterik adenovirüs sıklığının ve viral etkenlerin yaş ve mevsimsel dağılımının belirlenmesi amaçlanmıştır.Materyal-Metod: Bu çalışmada, 6999 dışkı örneği rotavirüs ve adenovirüs varlığı açısından incelenmiştir. Örnekler, Ocak 2013 ile Ağustos 2019 arasında, hastanemize akut gastroenterit şikayeti ile başvuran 0-17 yaş arası çocuklardan alınmıştır. Rotavirüs ve adenovirüs sıklığının hastaların cinsiyetlerine, yaşlarına ve mevsimlere göre dağılımı retrospektif olarak değerlendirilmiştir.Bulgular: Çalışmada incelenen numunelerin 1341 (%19.1)’inde viral antijen saptanmıştır. Pozitif sonuçlar arasında rotavirüs ve adenovirüs sıklığı sırasıyla %14.7 ve %4.4 olarak belirlenmiştir. 113 (%8,4) örnekte rotavirüs-adenovirüs birlikteliği tespit edilmiştir. Rotavirüs antijeni tüm yaş gruplarında görülse de, en yüksek %57.9 ile 0-2 yaş arası çocuklarda saptanmıştır. Ayrıca, vakaların mevsimsel dağılımı, rotavirüs enfeksiyonlarının en çok kış aylarında ve ilkbaharda gözlendiğini ancak adenovirüs enfeksiyonlarının yıl boyunca meydana geldiğini ortaya koymuştur.Sonuç: Rotavirüs-adenovirüs enfeksiyonları ülkemizde çocukluk çağı hastalıkları içerisinde sık rastlanan, hastanede yatışlara, morbidite ve mortaliteye neden olan önemli bir sağlık sorunudur. Akut gastroenterite karşı koruyucu yaklaşımların yanı sıra etkenin doğru ve hızlı bir şekilde tespit edilmesi, tedavinin geciktirilmeden verilmesi çok önemlidir.

Comparative in vitro activity of plazomicin and 4 older aminoglycosides was evaluated with broth microdilution in 714 blood isolates from 14 hospitals in Turkey. Isolates included Escherichia coli (n=320), Klebsiella spp. (n=294), Enterobacter spp. (n =69), Serratia marcescens (n=20). and Citrobacter spp. (n=11). Isolates resistant to older aminoglycosides (n=240) were screened for aminoglycoside modifying enzyme genes: aac(6')-Ib, aac(3)-Ia, aac(3)-IIa, ant(2 '')-Ia. Isolates with high MICs for plazomicin (n=41) were screened for 165 rRNA methyltransferase genes (armA, rmtA, rmtB, rmtC, rmtD, rmtE, rmtF, rmtG, rmtH, npmA) and 2 carbapenemase genes (blaOXA-48, blaNDM-1). Overall, resistance to plazomicin, amikacin, netilmicin, gentamicin, and tobramycin was 7.7%, 7.4%, 31.5%, 32.9%, and 34.7%, respectively. aac(6')-Ib and aac(3)-IIa were the most common AME genes. Co-occurrence of blaNDM-1 with armA and rmtC and blaOXA-48 with armA was striking. Enterobacter cloacae carrying rmtC+blaNDM-1, S. marcescens with armA+blaOXA-48, and rmtF+ blaOXA-48 in K. pneumoniae were reported for the first time. (C) 2020 Elsevier Inc. All rights reserved., Achaogen Inc., CA, USA, The authors would like to acknowledge Achaogen Inc., CA, USA, for providing plazomicin and partly funding the tests for in vitro susceptibilities and characterization of aminoglycoside resistance genes.

This study was designed to investigate antimicrobial properties ofnatural essential oils including; citronella, cinnamon, palmarosa, niaouli,clove, lavender, bergamot, lemon, grapefruit, petitgrain, peppermint, tea treeand eucalyptus from different oil sources. Datas taken from the disk diffusionassay indicate that cinnamon, niaouli, lavender, petitgrain and the tea treeoils have the most intense antibacterial effects on related microorganisms atthe concentration %100 (direct usage). Endpoints confirm results reported inthe past studies including the MIC assays on the related natural oils. Overall,natural oils have been used safely for many decades on the cosmeticformulations and this experiment emphasizes one more time the importance of thenatural oils usage in industry