Aspects related to biofilm production and antifungal susceptibility of clinically relevant yeasts of the genus Trichosporon.

Trichosporonosis corresponds to a systemic fungal disease that leads to high mortality rates and is frequently associated with medical devices. It affects immunosuppressed patients in particular and is strongly linked to acquired human immunodeficiency, organ and tissue transplants, and malignant hematologic diseases such as leukemia and lymphomas. Trichosporon infections have been increasingly reported worldwide; however, little information is available either about their characteristics or the causative microorganism. Thus, the aims of the present study were: to investigate 59 yeasts of the genus Trichosporon by verifying the biofilm formation capacity of isolates; to analyze the susceptibility patterns of planktonic cells against the antifungals fluconazole, itraconazole, amphotericin-B, voriconazole, and caspofungin by comparing European Committee for Antimicrobial Susceptibility Testing (EUCAST) broth microdilution technique with the commercial method Etest; and to assess the susceptibility patterns of biofilm cells (sessile) against the same antifungals through broth microdilution. The ability to form biofilm on the surface of polystyrene plates was noted for all isolates, and 54.3% of samples were considered strong producers. Comparison between the antifungal susceptibility techniques evidenced that Etest showed higher and discordant minimum inhibitory concentrations (MICs) from those obtained by the microdilution method, especially for fluconazole, itraconazole, and caspofungin. Considering the susceptibility of biofilms, most species had high MIC50 and MIC90 against the tested antifungals, showing 4-to-66-fold higher concentrations for amphotericin B and 2-to-33-fold greater concentrations for caspofungin. These results highlight the importance of further studies with Trichosporon spp. for comparison between laboratory findings and in vivo response, considering both the susceptibility tests and the behavior of biofilm cells against drugs.

This study investigated 59 isolates of the medically important yeast Trichosporon in relation to their ability to form biofilms and the susceptibility of biofilms to antifungal agents. All isolates were able to produce biofilms and biofilms showed lower antifungal susceptibility.

Virulence factors of Paracoccidioides brasiliensis as therapeutic targets: a review.

Paracoccidiodomycosis (PCM) is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis and Paracoccidioides lutzii. The disease requires long and complicated treatment. The aim of this review is to address the fungal virulence factors that could be the target of the development of new drugs for PCM treatment. Virulence factors favoring the process of fungal infection and pathogenicity are considered as a microbial attribute associated with host susceptibility. P. brasiliensis has some known virulence factors which are 43 kDa glycoprotein (gp 43) which is an important fungal antigen, 70 kDa glycoprotein (gp 70), the carbohydrates constituting the fungal cell wall α-1,3, glucan and ß-1,3-glucan, cell adhesion molecules and the presence of melanin pigments. The discovery and development of drugs that interact with these factors, such as inhibitors of ß-1,3-glucan, reduced synthesis of gp 43, inhibitors of melanin production, is of great importance for the treatment of PCM. The study of virulence factors favors the understanding of pathogen-host relationships, aiming to evaluate the possibility of developing new therapeutic targets and mechanisms that these molecules play in the infectious process, favoring the design of a more specific treatment for this disease.

Candida spp. and phagocytosis: multiple evasion mechanisms.

Invasive fungal infections are a global health problem, mainly in hospitals, where year by year hundreds of patients die because of these infections. Commensal yeasts may become pathogenic to human beings, affecting mainly immunocompromised patients. During infectious processes, the immune system uses phagocytes to eliminate invader microorganisms. In order to prevent or neutralize phagocyte attacks, pathogenic yeasts can use virulence factors to survive, as well as to colonize and infect the host. In this review, we describe how Candida spp., mainly Candida albicans, interact with phagocytes and use several factors that contribute to immune evasion. Polymorphism, biofilm formation, gene expression and enzyme production mediate distinct functions such as adhesion, invasion, oxidative stress response, proteolysis and escape from phagocytes. Fungal and human cells have similar structures and mechanisms that decrease the number of potential targets for antifungal drugs. Therefore, research on host-pathogen interaction may aid in the discovery of new targets and in the development of new drugs or treatments for these diseases and thus to save lives.

Comparative analysis of biofilm formation by Candida albicans and Candida krusei in different types of contact lenses.

OBJECTIVE: To evaluate the Candida krusei and Candida albicans biofilm formation abilities on 5 different types of contact lenses and compare their metabolic activities and biomass. METHODS: After biofilm formation by both the test species, their metabolic activity was assessed by the 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide reduction assay with menadione, while the biomass was determined by staining with 0.4% crystal violet dye for further statistical analysis. RESULTS: Both the Candida species could form biofilms on different types of contact lenses, with greater metabolic activities and lower biomass formation in rigid gas permeable lenses. CONCLUSION: Biofilm formation with greater metabolic activity and greater biomass were expected on soft contact lenses considering their surface hydrophobicity. However, the results demonstrated a greater metabolic activity on rigid contact lenses. This result has a great significance with regards to the increasing risk of microbial keratitis, although further studies are warranted to better elucidate the formation of biofilms on different types of contact lens materials in the future.

Combination efficacy of voriconazole and amphotericin B in the experimental disease in immunodeficient mice caused by fluconazole-resistant Cryptococcus neoformans.

The therapeutic efficacy of amphotericin B and voriconazole alone and in combination with one another were evaluated in immunodeficient mice (BALB/c-SCID) infected with a fluconazole-resistant strain of Cryptococcus neoformans var. grubii. The animals were infected intravenously with 3 × 10(5) cells and intraperitoneally treated with amphotericin B (1.5 mg/kg/day) in combination with voriconazole (40 mg/kg/days). Treatment began 1 day after inoculation and continued for 7 and 15 days post-inoculation. The treatments were evaluated by survival curves and yeast quantification (CFUs) in brain and lung tissues. Treatments for 15 days significantly promoted the survival of the animals compared to the control groups. Our results indicated that amphotericin B was effective in assuring longest-term survival of infected animals, but these animals still harbored the highest CFU of C. neoformans in lungs and brain at the end of the experiment. Voriconazole was not as effective alone, but in combination with amphotericin B, it prolonged survival for the second-longest time period and provided the lowest colonization of target organs by the fungus. None of the treatments were effective in complete eradication of the fungus in mice lungs and brain at the end of the experiment.

Exploring the bioactivity potential of Leonotis nepetifolia: phytochemical composition, antimicrobial and antileishmanial activities of extracts from different anatomical parts.

Leonotis nepetifolia (L.) Br. (Lamiaceae) is an African shrub popularly known as 'cordão-de-frade' in Brazil, traditionally used to treat infectious diseases, among other uses. This study aimed to investigate the phytochemical composition of hydroethanolic extracts from L. nepetifolia prepared from stems, leaves, roots and glomerulus, as well as their cytotoxicity, antileishmanial and antimicrobial activities. The chemical composition of the extracts was assessed by UPLC-ESI-MS/MS, whereas the antileishmanial activity was evaluated against promastigote and amastigote forms of Leishmania amazonensis. Cytotoxicity was tested on murine macrophages and the antimicrobial activity was investigated by a microdilution assay against several strains of fungi, Gram-positive and Gram-negative bacteria. The flavonoids apigenin, cirsiliol apigenin-7-O-glucoside, luteolin, luteolin-4'-O-glucoside, luteolin-4'-O- glucuronide and luteolin-7-O-glucoside were identified in all tested extracts. Extracts from leaves and roots showed more potent antileishmanial activity (IC50 32.90 µg mL-1 and 57.70 µg mL-1, respectively) against amastigotes forms in comparison to the other extracts. The leaf extract inhibited Bacillus cereus and Staphylococcus aureus growth (125 µg mL-1 and 100 µg mL-1, respectively), and also showed anti-Candida activity (10-125 µg mL-1). The biological effect can be related to the identified flavonoids. Our findings disclose the potential of L. nepetifolia as a source of bioactive compounds for the development of new therapeutic options for treating infectious diseases, especially flavonoids.

Glucosyl-1,2,3-triazoles derived from eugenol and analogues: Synthesis, anti-Candida activity, and molecular modeling studies in CYP-51.

This work describes the synthesis, anti-Candida, and molecular modeling studies of eighteen new glucosyl-1,2,3-triazoles derived from eugenol and correlated phenols. The new compounds were characterized by combined Fourier Transform Infrared, 1 H and 13 C nuclear magnetic resonance and spectroscopy of high-resolution mass spectrometry. The synthesized compounds did not show significant cytotoxicity against healthy fibroblast human cells (MCR-5) providing interesting selectivity indexes (SI) to active compounds. Considering the antifungal activity, nine compounds showed anti-Candida potential and the peracetylated triazoles 17 and 18 were the most promising ones. Eugenol derivative 17 was active against three species of Candida at 26.1-52.1 µM. This compound was four times more potent than fluconazole against Candida krusei and less toxic (SI > 6.6) against the MCR-5 cells than fluconazole (SI > 3.3) considering this strain. Dihydroeugenol derivative 18 showed similar activity to 17 and was four times more potent and less toxic than fluconazole against C. krusei. The deacetylated glucosides and non-glucosylated corresponding derivatives did not show considerable antifungal action, suggesting that the acetyl groups are essential for their anti-Candida activity. Molecular docking coupled with molecular dynamics showed that 14α-lanosterol demethylase is a feasible molecular target, since 17 and 18 could bind to this enzyme once deacetylated in vivo, thereby acting as prodrugs. Also, these studies demonstrated the importance of hydrophobic substituents at the phenyl ring.

Metabolic profiling of Candida clinical isolates of different species and infection sources.

Candida species are the most common cause of opportunistic fungal infections. Rapid identification and novel approaches for the characterization of these fungi are of great interest to improve the diagnosis and the knowledge about their pathogenic properties. This study aimed to characterize clinical isolates of Candida spp. by proteomics (MALDI-TOF MS) and metabolomics (1H-NMR), and to correlate their metabolic profiles with Candida species, source of infection and different virulence associated parameters. In particular, 49 Candida strains from different sources (blood, n = 15; vagina, n = 18; respiratory tract, n = 16), belonging mainly to C. albicans complex (61%), C. glabrata (20%) and C. parapsilosis (12%) species were used. Several extracellular and intracellular metabolites showed significantly different concentrations among isolates recovered from different sources of infection, as well as among different Candida species. These metabolites were mainly related to the glycolysis or gluconeogenesis, tricarboxylic acid cycle, nucleic acid synthesis and amino acid and lipid metabolism. Moreover, we found specific metabolic fingerprints associated with the ability to form biofilm, the antifungal resistance (i.e. caspofungin and fluconazole) and the production of secreted aspartyl proteinase. In conclusion, 1H-NMR-based metabolomics can be useful to deepen Candida spp. virulence and pathogenicity properties.

Medication association and immunomodulation: An approach in fungal diseases and in particular in the treatment of paracoccidioidomycosis.

Fungal infections have been increasing in recent decades, mainly affecting immunocompromised individuals, although certain mycoses, such as paracoccidioidomycosis (PCM), infect immunologically competent individuals. The major problems observed regarding fungal diseases are inadequate diagnosis, prolonged treatment time, the reduced number of drugs available for treatment, in addition to the fact that there are no vaccines for clinical use. Drug combination in order to immunomodulate the immune response is a new strategy used for the treatment of mycoses, since it is difficult to develop new antifungal drugs. The aim of this study is to present and analyze strategies recently suggested for the treatment of fungi of medical interest, in particular for PCM, such as the utilization of combinations of protein fractions or dead microorganisms, as vaccinal antigens, and cellular immunotherapy. We will also propose new therapeutic alternatives, such as lipids, vitamins, synthetic or natural products as well as the use of low intensity LASER therapy (LLLT) to modulate the immune response of the host, enhancing the efficiency of the existing treatments of mycoses of medical interest and in particular of PCM.

Leishmanicidal and antimicrobial activity of primin and primin-containing extracts from Miconia willdenowii.

As a part of an ongoing bioprospective project, searching for potential medicinal plants from the Brazilian Atlantic Forest, Miconia willdenowii was selected for its potential leishmanicidal and antimicrobial activities. The crude ethanolic extract of M. willdenowii showed an inhibition of 99.7% of the promastigote forms of Leishmania amazonensis at the concentration of 80 µg/mL. Further investigation of its antimicrobial activity against pathogenic fungi and Gram positive and negative bacteria, revealed a significant antimicrobial activity. A bioguided study with its liquid-liquid partition fractions revealed the hexane fraction (Hex) as the most active against Leishmania, inhibiting 99.2% and 46.9% of the protozoan at concentrations of 40 and 20 µg/mL, respectively. Hex also showed significant antimicrobial activity against Staphylococcus aureus and Candida krusei with IC50 of 15.6 and 62.5 µg/mL, respectively. Purification of Hex led to the isolation of 2-methoxy-6-pentyl-benzoquinone (1, also known as primin) as the active metabolite, probably responsible for the observed antimicrobial and anti-leishmania effects. Primin (1) disclosed leishmanicidal activity (IC50 = 1.25 µM), showing higher potency than the standard drug amphotericin B (IC50 = 5.08 µM), with additional antifungal effects against all tested fungi species. Compound 1 also showed significant activity against S. aureus (IC50 = 8.94 µM), showing a comparable potency with the reference drug chloramphenicol (IC50 = 6.19 µM), but with a potential cytotoxicity towards peripheral human blood mononuclear cells (CC50 = 255.15 µM). Here in, the antimicrobial and anti-L. amazonensis effects of M. willdenowii are reported for the first time, as well as Primin (1) as its probable bioactive metabolite.

Ozone against Pseudomonas aeruginosa biofilms in contact lenses storage cases.

Pseudomonas aeruginosa is associated with ocular infections such as keratitis. Multipurpose contact lens solutions can be used for washing, disinfection and storage of contact lenses, however, P. aeruginosa biofilm disinfection by this method is unsatisfactory. The present study aimed to investigate the effectiveness of ozonated water in reducing P. aeruginosa colony count. Lenses kept in storage cases were contaminated with P. aeruginosa and disinfected using ozonized water, chlorhexidine, ultrasound and multipurpose solutions. The multipurpose solutions and ultrasound methods reduced colony count from 1.17 to 1.63 log10 CFU/cm2 (92.93% to 97.31%), respectively, of P. aeruginosa biofilm cell viability when compared to the positive control. Both, ozonated water and chlorhexidine showed 7.42 log reduction in the number of viable cells of P. aeruginosa biofilm. As compared to chlorhexidine, ozonized water did not depose any known toxic residues, so that we recommend it as an alternative disinfectant solution for contact lenses storage cases.

Synthesis, activity, and docking studies of eugenol-based glucosides as new agents against Candida sp.

Seventeen new synthetic derivatives of eugenol (6, 8-15 and 8'-15') were planned following literature reports on antifungal activities of nitroeugenol and eugenol glucoside. The anti-Candida activity of these compounds was investigated by in vitro assay, and the cytotoxicity evaluation was performed with the most active compounds. The peracetylated glucosides presented better biological results than their hydroxylated analogues. The glucoside 11, a 4-nitrobenzamide, showed the best potency (MIC50 range 11.0-151.84 µm), the wider spectrum of action, and overall the best selectivity indexes, especially against C. tropicalis (~30) and C. krusei (~15). To investigate its possible mechanism of action, glucoside 11 was subjected to molecular docking studies with Candida sp. enzymes involved in ergosterol biosynthesis. Results have shown that the peracetyl glucosyl moiety and the 4-nitrobenzamide group in 11 are effectively involved in its high affinity with the active site of squalene epoxidase.

The "in vitro" antifungal activity evaluation of propolis G12 ethanol extract on Cryptococcus neoformans.

Cryptococcosis is a worldwide disease caused by the etiological agent Cryptococcus neoformans. It affects mainly immunocompromised humans. It is relatively rare in animals only affecting those that have received prolonged antibiotic therapy. The propolis is a resin that can present several biological properties, including antibacterial, antifungal and antiviral activities. The standard strain C. neoformans ATTC 90112 was used to the antifungal evaluation. The tests were realized with propolis ethanol extract (PEE) G12 in concentrations from 0.1 to 1.6 mg mL-1. The evaluation of MIC and MFC were done according to DUARTE (2002)5. The inhibitory effect of PEE G12 on the fungal growing was seen at the concentration of 0.2 mg mL-1 and 1.6 mg mL-1 was considered a fungicidal one.

Serotype and mating type characterization of Cryptococcus neoformans by multiplex PCR.

Cryptococcus neoformans is an encapsulated yeast, etiological agent of cryptococcosis. The species is commonly associated with pigeon droppings and plant materials. The aim of the present work was to verify the presence of the yeast in pigeon droppings, and to identify the isolates obtained in serotypes and mating types (MAT). Ten samples of pigeon droppings were collected in the rural area of the city of Alfenas, Brazil. Samples were inoculated in agar Niger medium for fungal isolation and 22 isolates with characteristics of C. neoformans were obtained. The serotypes and MAT were determined by multiplex PCR using specific primers. Serotypes were also determined by using the Kit Crypto Check. Among the 22 samples evaluated, eight were identified as C. neoformans by classic identification tests. These samples were characterized as serotype A by the Kit Crypto check and as serotype A MAT alpha by the multiplex PCR. The present study reinforces the evidence that pigeon droppings are a reservoir for C. neoformans and confirms the prevalence of C. neoformans var. grubii (A alpha) among environmental isolates. It also demonstrates that multiplex PCR is an acceptable alternative for serotype analysis because it reduces the costs for each reaction and analyses serotype and MAT simultaneously.

[Behaviour azole fungicide and fluconazole in Cryptococcus neoformans clinical and environmental isolates]. / Comportamento de amostras ambientais e clínicas de Cryptococcus neoformans frente a fungicidas de uso agronômico e ao fluconazol.

The activity of azole fungicides for agronomical use (epoxiconazole, difenoconazole and cyproconazole) was evaluated in comparison with the therapeutic antifungal agent fluconazole, on 23 environmental samples of Cryptococcus neoformans var neoformans isolated from pigeon feces that were collected from farms with agricultural practices using azole compounds, and on 11 clinical samples isolated from patients with cryptococcosis. Sensitivity tests were performed using the agar dilution technique. The minimum inhibitory concentration capable of inhibiting 50% of the environmental isolates (MIC 50) was 6.00 microg/ml to epoxiconazole, 1.00 microg/ml for difenoconazole, 2.00 microg/ml for cyproconazole and 64.00 microg/ml for fluconazole. Among the clinical isolates the MIC 50 values were 2.00 microg/ml, 0.38 microg/ml, 1.00 microg/ml and 16.00 microg/ml for epoxiconazole, difenoconazole, cyproconazole and fluconazole, respectively. The MIC 50 values for environmental isolates were greater than the MIC 50 values for clinical isolates. In our study, in relation to the same antifungal agent, the environmental samples presented significantly different behaviour in relation to the clinical samples (p<0.05). Differences in the MIC values (p<0.05) presented by fluconazole and the other antifungal agents for agronomical use, both in the environmental isolates and in the clinical isolates, were also observed.

Comparative analysis of biofilm formation by Candida albicans and Candida krusei in different types of contact lenses / Análise comparativa da formação de biofilmes, por Candida albicans e Candida krusei, em diferentes tipos de lentes de contato

ABSTRACT Objective: To evaluate the Candida krusei and Candida albicans biofilm formation abilities on 5 different types of contact lenses and compare their metabolic activities and biomass. Methods: After biofilm formation by both the test species, their metabolic activity was assessed by the 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide reduction assay with menadione, while the biomass was determined by staining with 0.4% crystal violet dye for further statistical analysis. Results: Both the Candida species could form biofilms on different types of contact lenses, with greater metabolic activities and lower biomass formation in rigid gas permeable lenses. Conclusion: Biofilm formation with greater metabolic activity and greater biomass were expected on soft contact lenses considering their surface hydrophobicity. However, the results demonstrated a greater metabolic activity on rigid contact lenses. This result has a great significance with regards to the increasing risk of microbial keratitis, although further studies are warranted to better elucidate the formation of biofilms on different types of contact lens materials in the future.

RESUMO Objetivo: Avaliar a capacidade de formação de bio­filmes de Candida krusei e Candida albicans em cinco tipos de lentes de contato, comparando atividade metabólica e biomassa dos mesmos. Métodos: Após a formação de biofilme de ambas as espécies, a atividade metabólica foi avaliada por ensaio de redução 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-te­tra­zolium-5-carboxanilide com Menadiona, e a biomassa foi avaliada por coloração com Cristal Violeta 0,4% para posterior análise estatística. Resultados: Ambas as espécies de Candida foram capazes de formar biofilmes nos diferentes tipos de lentes de contato, havendo em lentes rígidas gás permeável maior atividade metabólica e menor biomassa formada. Conclusão: Esperava-se a obtenção de biofilmes de maior atividade metabólica e maior biomassa em lentes de contato gelatinosas com base no fundamento da Hidrofobicidade Superficial. Porém, o resultado apontou para maior atividade metabólica em lentes de contato rígidas. Apesar de observados resultados significativos, trata-se de um assunto de grande importância frente ao aumento do número de ceratites microbianas, mostrando-se necessários outros estudos para melhor elucidar a formação de biofilmes em diferentes tipos de materiais de lentes de contato.

Virulence profile of strains of Cryptococcus neoformans var. grubii evaluated by experimental infection in BALB/c mice and correlation with exoenzyme activity.

To evaluate the virulence profile of strains of Cryptococcus neoformans var. grubii, 62 strains of this yeast were inoculated into BALB/c mice. It was found that 69 % of the strains were significantly more lethal to the mice and were recovered from a higher percentage (60 %) of the organs compared with the other 31 % of the strains, which were recovered from 35 % of organs tested. Those strains that provoked higher death rates were also recovered from the central nervous system at a higher rate (84 %) than the less lethal strains (32 %). This finding led to an investigation of the factors that enhanced the capacity for neurological infection and death of the animals. The results of this study suggested that environmental strains present different degrees of virulence. The correlation of exoenzyme production before and after inoculation and between the groups of mice indicated that exoenzyme production had no influence on differences in virulence among the strains studied.

Candida glabrata among Candida spp. from environmental health practitioners of a Brazilian Hospital.

The incidence of the species Candida albicans and non-albicans Candida was evaluated in a Brazilian Tertiary Hospital from the environment and health practitioners. In a 12-month period we had a total positivity of 19.65% of Candida spp. The most recurring non-albicans Candida species was C. glabrata (37.62%), generally considered a species of low virulence, but with a higher mortality rate than C. albicans. Subsequently, C. parapsilosis (25.74%) and C. tropicalis (16.86%) were the second and third most commonly isolated species. Considering the total samples collected from the emergency room and from the inpatient and the pediatric sector, 19.10% were positive for Candida spp., with the predominance of non-albicans Candida species (89.42%). The high percentage of positivity occurred in the hands (24.32%) and the lab coats (21.88%) of the health care assistants. No sample of C. albicans presented a profile of resistance to the drugs. All the non-albicans Candida species presented a decreased susceptibility to miconazole and itraconazole, but they were susceptible to nystatin. Most of the isolates were susceptible to fluconazole and amphotericin B. As expected, a high resistance rate was observed in C. glabrata and C. krusei, which are intrinsically less susceptible to this antifungal agent. The contamination of environmental surfaces by Candida spp. through hand touching may facilitate the occurrence of Candida infections predominantly in immunocompromised patients. In addition to that, the antifungal agents used should be carefully evaluated considering local epidemiologic trends in Candida spp. infections, so that therapeutic choices may be better guided.

New Eugenol Glucoside-based Derivative Shows Fungistatic and Fungicidal Activity against Opportunistic Candida glabrata.

A new series of glucosides modified in their saccharide units were synthesized, evaluated against Candida sp., and compared to prototype 1, an eugenol tetracetyl glucoside previously synthesized and shown to be active against Candida glabrata. Among the new glucosides, benzyl derivative 5 was the most promising, showing fungistatic activity at IC50 18.1 µm against Candida glabrata (threefold higher than fluconazole) and fungicidal activity with a low IC90 value of 36.2 µm. Moreover, the cytotoxic activity of compound 5 (CC50 : 580.9 µm), tested in peripheral blood mononuclear cells, suggests its potential as an agent to treat Candida glabrata infections, with a selectivity index of 32. The new eugenol glucoside 5 may be considered as a novel structural pattern in the development of new anti-Candida drugs.

Synthesis and antimicrobial activity of 6-triazolo-6-deoxy eugenol glucosides.

A new series of 1,2,3-triazole eugenol glucosides were synthesized. The new compound structures were confirmed by MS, (1)H NMR and (13)C NMR. All of the synthesized compounds were screened for antimicrobial and cytotoxic activity. Five compounds exerted significant activity against the Gram-negative bacteria Salmonella typhimurium with low IC50 values (49.73-68.53 µΜ), and seven compounds were active against the Gram-positive bacteria Micrococcus luteus (42.89-210.94 µM). In vitro cytotoxicity on mouse spleen cells was also evaluated. One compound bearing a phenyl substituent at the triazole ring showed good activity against Salmonella typhimurium (49.73 µM) and low toxicity to normal cells (CC50=157.83 µM). Thus, the compounds herein can be considered for further modification for improving their antibacterial activity or obtaining novel antibacterial drug candidates.