Yeast Candida Albicans Research Articles

Proton Transfer Salt and Metal Complexes of 4,4'-Ethylenedipyridine and 2,3-Pyrazinedicarboxylic Acid: Synthesis, Structural Characterization and Biological Activity

In this study, a new salt {(H2BPE)(PDA), 1} synthesized from 4,4’-ethylenedipyridine (BPE) with 2,3 pyrazinedicarboxylic acid (H2PDA) and its complexes Fe(III) {(H2BPE)[Fe2(PDA)(H2O)4]n, 2} and Ni(II) {[Ni(PDA)(BPE)2(H2O)2]n.H2O, 3}, were synthesized and defined by using 1H and 13C NMR, TG-DTA, IR, UV Vis, elemental analysis, magnetic susceptibility techniques. In addition, antibacterial and antifungal activities of starting materials and synthesized compounds against Candida albicans yeast and Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli and Listeria monocytogenes bacteria were investigated using the microdilution method and compared with existing antibiotics (Cefepime, Vancomycin, Levofloxacin and Fluconazole). Compounds 1-3 were observed to have activity against yeast and bacteria. In particular, compound 3 (7.80 µg/mL) against E. faecalis, compounds 3 (7.80 µg/mL) against B. subtilis bacteria, and compound 1 (15.60 µg/mL) against C. albicans yeast. showed better activity than control compounds.

Full Circle: When HSFs bring the heat-mapping the transcriptional circuitries of HSF-type regulators in Candida albicans.

Heat shock factor (HSF)-type regulators are stress-responsive transcription factors widely distributed among eukaryotes, including fungi. They carry a four-stranded winged helix-turn-helix DNA-binding domain considered as the signature domain for HSFs. The genome of the opportunistic yeast Candida albicans encodes four HSF members, namely, Sfl1, Sfl2, Skn7, and the essential regulator, Hsf1. C. albicans HSFs do not only respond to heat shock and/or temperature variation but also to CO2 levels, oxidative stress, and quorum sensing, acting this way as central decision makers. In this minireview, I follow on the heels of my mSphere of Influence commentary (2020) to provide an overview of the repertoire of HSF regulators in Saccharomyces cerevisiae and C. albicans and describe how their genetic perturbation in C. albicans, coupled with genome-wide expression and location analyses, allow to map their transcriptional circuitry. I highlight how they can regulate, in common, a crucial developmental program: filamentous growth.

Engineering Adhesion of the Probiotic Strain Escherichia coli Nissle to the Fungal Pathogen Candida albicans.

Engineering live biotherapeutic products against fungal pathogens such as Candida albicans has been suggested as a means to tackle the increasing threat of fungal infections and the development of resistance to classical antifungal treatments. One important challenge in the design of live therapeutics is to control their localization inside the human body. The specific binding capability to target organisms or tissues would greatly increase their effectiveness by increasing the local concentration of effector molecules at the site of infection. In this study, we utilized surface display of carbohydrate binding domains to enable the probiotic E. coli Nissle 1917 to adhere specifically to the pathogenic yeast Candida albicans. Binding was quantified using a newly developed method based on the automated analysis of microscopic images. In addition to a rationally selected chitin binding domain, a synthetic peptide of identical length but distinct sequence also conferred binding. Efficient binding was specific to fungal hyphae, the invasive form of C. albicans, while the yeast form, as well as abiotic cellulose and PET particles, was only weakly recognized.

New Shikimic Acid Derivatives From the Marine-Derived Actinomycete Streptomyces sp. G666 and Their Antimicrobial Activities.

Analysis of an antimicrobial extract from the agar-based culture of the marine-derived actinomycete Streptomyces sp. G666 led to the isolation of three new shikimic acid derivatives, streptomine A-C (1-3), along with five known compounds (4-8). Their structures were established by their spectral data analyses, including MS and NMR. All the isolated compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Three new compounds 1-3 demonstrated selective antimicrobial activity against Gram-positive Enterococcus faecalis with MIC values ranging from 32 to 64µg/mL. Compound 3 exhibited the highest inhibitory effect against E. faecalis with an MIC value of 32µg/mL. Compound 4 selectively inhibited Escherichia coli with an MIC value of 128µg/mL. In addition, compounds 1-3 moderately inhibited the yeast Candida albicans with the same MIC value of 16µg/mL. Unfortunately, most of isolated compounds were inactive against Gram-negative bacteria E. coli, Pseudomonas aeruginosa, and Salmonella enterica.

Nanosilver-Biopolymer-Silica Composites: Preparation, and Structural and Adsorption Analysis with Evaluation of Antimicrobial Properties.

In this article, we report on the research on the synthesis of composites based on a porous, highly ordered silica material modified by a metallic nanophase and chitosan biofilm. Due to the ordered pore system of the SBA-15 silica, this material proved to be a good carrier for both the biologically active nanophase (highly dispersed silver nanoparticles, AgNPs) and the adsorption active phase (chitosan). The antimicrobial susceptibility was determined against Gram-positive Staphylococcus aureus ATCC 25923, Gram-negative bacterial strains (Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603, and Pseudomonas aeruginosa ATCC 27853), and yeast Candida albicans ATCC 90028. The zones of microbial growth inhibition correlated with the content of silver nanoparticles deposited in the composites and were the largest for C. albicans (14-21 mm) and S. aureus (12-17 mm). The suitability of the composites for the purification of water and wastewater from anionic pollutants was evaluated based on kinetic and equilibrium adsorption studies for the dye Acid Red 88. The composite with the highest amount of the chitosan component showed the greatest adsorption capacity (am) of 0.57 mmol/g and the most effective kinetics with a rate constant (log k) and half-time (t0.5) of -0.21 and 1.62 min, respectively. Due to their great practical importance, AgNP-chitosan-silica composites can aspire to be classified as functional materials combining the environmental problem with microbiological activity.

Ketoconazole-Fumaric Acid Pharmaceutical Cocrystal: From Formulation Design for Bioavailability Improvement to Biocompatibility Testing and Antifungal Efficacy Evaluation.

Development of cocrystals through crystal engineering is a viable strategy to formulate poorly water-soluble active pharmaceutical ingredients as stable crystalline solid forms with enhanced bioavailability. This study presents a controlled cocrystallization process by cooling for the 1:1 cocrystal of Ketoconazole, an antifungal class II drug with the Fumaric acid coformer. This was successfully set up following the meta-stable zone width determination in acetone-water 4:6 (V/V) and pure ethanol. Considering the optimal crystallization data, laboratory scale-up processes were carried out at 1 g batch size, efficiently delivering the cocrystal in high yields up to 90% pure and single phase as revealed by powder X-ray diffraction. Biological assays in vitro showed improved viability and oxidative damage of the cocrystal over Ketoconazole on human dermal fibroblasts and hepatocarcinoma cells; in vivo, on Wistar rats, the cocrystal increased oral Ketoconazole bioavailability with transient minor biochemical transaminases increases and without histological liver alterations. Locally on Balb C mice, it induced no epicutaneuous sensitization. A molecular docking study conducted on sterol 14α-demethylase (CYP51) enzyme from the pathogenic yeast Candida albicans revealed that the cocrystal interacts more efficiently with the enzyme compared to Ketoconazole, indicating that the coformer enhances the binding affinity of the active ingredient.

One-Step Synthesis of Antimicrobial Polypeptide-Selenium Nanoparticles Exhibiting Broad-Spectrum Efficacy against Bacteria and Fungi with Superior Resistance Prevention.

The growing threat of antimicrobial resistance (AMR) necessitates innovative strategies beyond conventional antibiotics. In response, we developed a rapid one-step method to sythesize antimicrobial peptide (AMP) ε-poly-L-lysine stabilized selenium nanoparticles (ε-PL-Se NPs). These polycrystalline NPs with highly positive net surface charges, exhibited superior antimicrobial activity against a broad panel of pathogens, including the Gram-positive and -negative bacteria Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa and their drug-resistant counterparts, as well as the yeast Candida albicans. Notably, 10PL-Se NPs exhibited 6-log reduction of methicillin-resistant S. aureus (MRSA) at a concentration of 5 μg/mL within 90 min, with minimum bactericidal concentrations (MBCs) below 50 μg/mL for all tested bacterial strains. The minimum fungicidal concentration (MFC) of 10PL-Se NPs against C. albicans was 26 ± 10 μg/mL. Crucially, bacteria exposed to ε-PL-Se NPs exhibited significantly delayed resistance development compared to the conventional antibiotic kanamycin. S. aureus developed resistance to kanamycin after ∼72 generations, whereas resistance to 10PL-Se NPs emerged after ∼216 generations. Remarkably, E. coli showed resistance to kanamycin after ∼39 generations but failed to develop resistance to 10PL-Se NPs even after 300 generations. This work highlights the synergistic interactions between ε-PL and Se NPs, offering a robust and scalable strategy to combat AMR.

β-1,6-Glucan plays a central role in the structure and remodeling of the bilaminate fungal cell wall.

The cell wall of human fungal pathogens plays critical roles as an architectural scaffold and as a target and modulator of the host immune response. Although the cell wall of the pathogenic yeast Candida albicans is intensively studied, one of the major fibrillar components in its cell wall, β-1,6-glucan, has been largely neglected. Here, we show that β-1,6-glucan is essential for bilayered cell wall organization, cell wall integrity, and filamentous growth. For the first time, we show that β-1,6-glucan production compensates the defect in mannan elongation in the outer layer of the cell wall. In addition, β-1,6-glucan dynamics are also coordinated by host environmental stimuli and stresses with wall remodeling, where the regulation of β-1,6-glucan structure and chain length is a crucial process. As we point out that β-1,6-glucan is exposed at the yeast surface and modulate immune response, β-1,6-glucan must be considered a key factor in host-pathogen interactions.

The Leaf Essential Oils of Syzygium oblatum and Syzygium abortivum: Chemical Composition, Antimicrobial Activity, and Molecular Docking Study

Background and Objectives Syzygium (the family Myrtaceae) is a well-known genus in the field of food chemistry and medicinal purposes. The current study aims to provide a chemical analysis of essential oils from the fresh leaves of two Vietnamese Syzygium species Syzygium oblatum (Roxb.) Wall. ex Steudel and S. abortivum (Gagnep.) Merr. & L.M.Perry. Methods Chemical compounds in essential oils were identified using GC-FID/MS (gas chromatography-flame ionization detection/mass spectrometry) analysis. The broth microdilution method was used for the antimicrobial assay. Docking stimulation aided experimental results. Results ( E)-Caryophyllene (27.89%), α-selinene (18.34%), β-selinene (17.48%), and α-pinene (5.20%) were identified to be the main compounds in S. oblatum leaf essential oil, whereas the leaf essential oil of S. abortivum was dominated by ( E)-caryophyllene (19.56%), δ-cadinene (11.03%), germacrene D (10.34%), and γ-muurolene (5.50%). It noted that both studied oil samples with the MIC/IC50 values of 8-32 µg/mL/4.56-10.37 µg/mL were comparable to the standard drugs in antimicrobial experiments against the Gram-positive bacteria Bacillus cereus and Enterococcus faecalis, and yeast Candida albicans. Molecular docking results showed that the main compound ( E)-caryophyllene primarily formed hydrophobic interactions with the microbial proteins C. albicans N-myristoyl transferase B. cereus patB1, and E. faecalis carbamate kinase with the binding affinities of −6.969, −6.342, and −5.530 kcal/mol, respectively Conclusion It is advised to isolate the main chemicals and conduct in vivo antibacterial experiments for both essential oils and their main compounds.

Cm-p5, a molluscan-derived antifungal peptide exerts its activity by a membrane surface covering in a non-penetrating mode

Amidst the health crisis caused by the rise of multi-resistant pathogenic microorganisms, Antimicrobial Peptides (AMPs) have emerged as a potential alternative to traditional antibiotics. In this sense, Cm-p5 is an AMP with fungistatic activity against the yeast Candida albicans. Its antimicrobial activity and selectivity have been well characterized; however, the mechanism of action is still unknown. This study used biophysical approaches to gain insight into how this peptide exerts its activity. Stability and fluidity of lipid membrane were explored by liposome leakage and Laurdan generalized polarization (GP) respectively, suggesting that Cm-p5 does not perturb lipid membranes even at very high concentrations (≥100µm.L-1). Likewise, no depolarizing action was observed using 3,3'-propil-2,2'-thyodicarbocianine, a potential membrane fluorescent reporter, with C. albicans cells or the corresponding liposome models. Changes in liposome size were analyzed by Dynamic Light Scattering (DLS) data, indicating that Cm-p5 covers the vesicular surface slightly increasing liposome hydrodynamic size, without liposome rupture. These results were further corroborated with Langmuir monolayer isotherms, where no significant changes in lateral pressure or area per lipid were detected, indicating little or no insertion. Finally, data obtained from molecular dynamics simulations aligned with in vitro observations, whereby Cm-p5 slightly interacted with the fungal membrane model surface without causing significant perturbation. These results suggest Cm-p5 is not a pore-forming anti-fungal peptide and that other mechanisms of action on the membrane as some limitation of fungal nutrition or receptor-dependent transduction for depressing growth development should be explored.

Polyphenol content, Antioxidant and Antimicrobial activities of Hyoscyamus albus L. Aerial extracts

This study involved the investigation of polyphenol and flavonoid content, the antioxidant and antimicrobial potential of Hyoscyamus albus extracts. Four sub-fractions were obtained by successive extraction by using methanol, chloroform, and ethyl acetate. The extracts' yields were counted and the total phenolic (TPC) and flavonoid content (TFC) were assessed via spectrophotometric methods. The extracts' antioxidant activity was investigated by using DPPH test, Total Antioxidant Capacity (TAC), Hydroxyl radical scavenging potency and β-Carotene/linoleic acid bleaching assay. The antimicrobial potential was valued against 08 strains of pathogenic bacteria and yeast. The results revealed that the CrE yielded the highest extracted value (13,34%) and the lowest percentage yield was that of EAE (1.46%). Interestingly, the EAE gave higher amounts of polyphenols (186.55 mg GAEq/gE), whereas the ChE showed the lowest content (45.19mg GAEq/gE). Notably, both the EAE and ChE fractions contained the highest levels of flavonoids, correlating with their antioxidant activity. Specifically, the EAE displayed the highest DPPH scavenging activity (p<0.001) with IC50 of 21μg/ml and revealed the strongest total antioxidant capacity (EC50 = 50μg/ml). While the CrE is regarded as an excellent OH quencher with a weaker IC50 close to the synthetic reference standard (p<0.001). However, ChE showed greater inhibition of β-carotene bleaching and impeded linoleic acid oxidation. Furthermore, the tested extracts exhibited different degrees of antimicrobial activity. The EAE was the only extract that proved effective against the yeast (Candida albicans). The current study confirmed the important antioxidant action, as well as the significant antimicrobial effects of Hyoscyamus albus extracts. These findings firmly underpin the traditional applications of this herb for treating ailments and infection, and could in fact be a source of natural antioxidant, and antibacterial compounds.

Photodynamic inactivation strategies for maximizing antifungal effect against Sporothrix spp. and Candida albicans in an in vitro investigation.

Sporotrichosis is a zoonotic disease caused by the dimorphic fungus Sporothrix spp., leading to skin lesions that can, in some cases, progress and result in the death of infected individuals. Candida albicans is another fungus involved in several skin, oral, and vaginal mucosal infections. Fungal diseases are concerning due to increasing incidence and the limited variety of antifungal classes available for treatment. Furthermore, antifungal medications can cause various side effects, exacerbated by their prolonged use during infection treatment. There is a need to explore alternatives to conventional drugs that are effective, fast, and safe in combating sporotrichosis. This study aimed to achieve in vitro elimination of the fungi Sporothrix brasiliensis and Sporothrix schenckii through Photodynamic Inactivation (PDI), using curcumin as a photosensitizer and in combination with antifungal agents used in the treatment of sporotrichosis. Yeasts of Candida albicans, Sporothrix brasiliensis, and Sporothrix schenckii were subjected to Photodynamic Inactivation (PDI) using light at a wavelength of 450 ± 10 nm, irradiance of 35 mW/cm2, delivering a fluence of 31.5 J/cm2, with curcumin as the photosensitizer at doses ranging from 0.75 to 150 μg/mL. After determining the Minimum Inhibitory Concentration (MIC) values of the antifungal drugs itraconazole, ketoconazole, and potassium iodide, sub-MIC doses of these antifungals were combined with sub-MIC doses of curcumin in a new PDI session. Photodynamic inactivation is a promising technique in the treatment of sporotrichosis, as well as its combination with antifungals. The combination of curcumin in concentrations ranging from 0.75 g/mL a 7.5 g/mL with sub-MIC concentrations of itraconazole, ketoconazole, and potassium iodide was able to completely inactivate the fungi C. albicans, S. brasiliensis and S. schenckii, indicating that PDI may increase the effectiveness of antifungals. However, further studies are needed to establish protocols for future clinical applications.

Adaptation of Candida albicans to specific host environments by gain-of-function mutations in transcription factors.

The yeast Candida albicans is usually a harmless member of the normal microbiota in healthy persons but is also a major fungal pathogen that can colonize and infect almost every human tissue. A successful adaptation to environmental changes encountered in different host niches requires an appropriate regulation of gene expression. The zinc cluster transcription factors are the largest family of transcriptional regulators in C. albicans and are involved in the control of virtually all aspects of its biology. Under certain circumstances, mutations in these transcription factors that alter their activity and the expression of their target genes confer a selective advantage, which results in the emergence of phenotypically altered variants that are better adapted to new environmental challenges. This review describes how gain-of-function mutations in different zinc cluster transcription factors enable C. albicans to overcome antifungal therapy and to successfully establish itself in specific host niches.

Comparison between Conventional Methods and Molecular Diagnosis for Candida albicans and Candida dubliniensis isolated from Cancer Patients Infected with Oral Candidiasis

Abstract Background: Two related pathogenic yeast species, Candida albicans and Candida dubliniensis share many phenotypic and microscopic diagnostic characteristics, in addition to the similarity in the characteristics of diagnosis. Objectives: The present study aimed to diagnose both yeast cells and compare them at the level of the percentage of similarities and differences according to the traditional methods and molecular approaches, which are considered more accurate and sensitive. Materials and Methods: The ability to form germ tubes was conducted for C. albicans and C. dubliniensis. The identification using biochemical tests, VITEK techniques, and molecular techniques was also conducted. Results: The results showed that both pathogenic yeast cells are similar in phenotypic and biochemical diagnosis, whereas the results of molecular diagnosis showed a difference between them, as well as the results of the drug sensitivity test, showed that the two types of yeast cells are sensitive to the antifungal drugs. The current study also showed the diagnosis of new isolates of the two species for the first time, which can be attributed to the occurrence of genetic mutations in them. Conclusion: Both types of pathogenic yeasts that were diagnosed in the current study are the important pathological types prevalent in cancer patients, especially in oral cavity infections, and they are similar to a large extent in terms of phenotypic and diagnostic characteristics.

Sesquiterpene Hydrocarbon-rich Essential Oil from Teucrium viscidum Blume and its Antimicrobial and Mosquito Larvicidal Activities

Objectives This study aimed to investigate the essential oil extracted from the aerial parts of Teucrium viscidum Blume, a perennial herb belonging to the Lamiaceae family, collected in Vietnam. The focus was on determining the essential oil's chemical composition and evaluating its antimicrobial and mosquito larvicidal activities. Methods The essential oil of T. viscidum was analyzed using GC–FID/MS to identify its chemical constituents. The antimicrobial activity was assessed against seven microorganisms using the broth microdilution method to determine minimum inhibitory concentration (MIC) and half-maximal inhibitory concentration (IC50) values. The larvicidal activity was evaluated against Culex quinquefasciatus larvae, with lethal concentration (LC50 and LC90) values calculated after 24 and 48 h of exposure. Results Chemical analysis revealed that the essential oil of T. viscidum was predominantly composed of sesquiterpene hydrocarbons, with ( E)-caryophyllene (47.91%) and germacrene D (19.17%) as the major constituents. The essential oil exhibited significant antimicrobial activity against three Gram-positive bacteria ( Enterococcus faecalis, Staphylococcus aureus, and Bacillus cereus), one Gram-negative bacterium ( Pseudomonas aeruginosa), and one yeast ( Candida albicans), with MIC values ranging from 32 to 64 μg/mL and IC50 values ranging from 9.56 to 24.07 μg/mL. The mosquito larvicidal activity of the essential oil showed strong efficacy against C. quinquefasciatus larvae, with LC50 values of 23.07 μg/mL after 24 h and 19.67 μg/mL after 48 h, and LC90 values of 32.90 μg/mL at 24 h and 29.99 μg/mL at 48 h, indicating increased effectiveness with prolonged exposure. Conclusion This study provides a comprehensive analysis of the chemical composition and biological activities of T. viscidum essential oil. The findings highlight its potent antimicrobial and mosquito larvicidal properties, suggesting it as a promising natural alternative to synthetic antimicrobial agents and insecticides. Further research is warranted to explore its mechanisms of action and potential applications in pharmaceuticals and pest control.

Fludioxonil does not antagonize propiconazole activity against Geotrichum candidum.

Fludioxonil and propiconazole are frequently used fungicides for managing fungal diseases in specialty crops. They are often used in mixture to manage brown rot caused by Monilinia fructicola and sour rot caused by the yeast-like fungus Geotrichum candidum,respectively, on stone fruits. Research indicated, however, that fludioxonil can increase the expression of the ATP-binding cassette transporters CDR1 and CDR2 in the yeast Candida albicans, leading to increased resistance to DMI fungicides. In this study, mycelial growth assays and detached fruit assays were conducted with G. candidum isolates of varying sensitivity to propiconazole to investigate potential antagonism between the two active ingredients. Isolates sensitive, reduced-sensitive, and resistant to propiconazole were able to grow with or without 20 µg/ml fludioxonil on PDA containing up to 0, 3, and 30 μg/ml propiconazole and on water agar containing up to 7.5, 7.5, and 30 μg/ml propiconazole, respectively, and no antagonistic interactions were detected. Propiconazole controlled disease with or without 20 µg/ml fludioxonil equally on detached cherry fruit caused by isolates with different DMI sensitivity phenotypes. Our results indicated no detectable antagonism between fludioxonil and propiconazole that would interfere with the mixture's ability to manage sour rot of cherry.

Cu(II) complexes of 2-methoxy-5-sulfamoylbenzoic acid and 2-aminopyridine derivatives: Synthesis, characterization and antimicrobial activity

Three novel mixed ligand Cu(II) complexes {[Cu(sba)2(X)2].2H2O, X = 2a3NO24mp for 1, 2a5Clp for 2, 2a5NO2p for 3} obtained from 2-methoxy-5-sulfamoylbenzoic acid (Hsba) with 2-amino-3-nitro-4-methylpyridine (2a3NO24mp), 2-amino-5-chloropyridine (2a5Clp) and 2-amino-5-nitropyridine (2a5NO2p), respectively, have been prepared. The structures of 1-3 FT-IR, AAS, UV, molar conductivity, magnetic susceptibility, and charge balance as suggested by previous studies have been characterized. According to spectroscopic findings, the structures of 1-3 can be postulated as tetrahedral complexes. Furthermore, all compounds have been screened for their antibacterial and antifungal activities against Pseudomonas aeruginosa (ATCC 27853), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (NRRL B-767), Bacillus subtilis, Escherichia coli (ATCC25922) and Listeria monocytogenes (ATCC 7644) bacteria and Candida albicans (F89) yeast. The outcomes are contrasted with those of the control substances (Fluconazole as antifungal and Cefepime, Levofloxacin, and Vancomycin as antibacterial agents). The best activity values of the compounds are Cu(Ac)2.2H2O for S. aureus bacteria, 2a5NO2p for E. coli bacteria, 2 for P. aeruginoa bacteria, Hsba, 2a3NO24mp and 2a5NO2p for L. monocytogenes bacteria, Cu(Ac)2.2H2O, 2a3NO24mp, 2a5Clp, 2a5NO2p and 2 for E. faecalis bacteria, all compounds (except 3) for B. subtilis bacteria, and 2a5NO2p and 1 were observed for C. albicans yeast.

Reactivity of (3‐(4‐Fluorophenyl)oxyran‐2‐yl)(naphthalene‐2‐yl)methanone Toward Some Nucleophiles for Preparing Promising Agents with Antimicrobial and Antioxidant Activities

Abstract(3‐(4‐Fluorophenyl)oxyran‐2‐yl)(naphthalene‐2‐yl)methanone 2 was prepared from the reaction of 3‐(4‐fluorophenyl)‐1‐(naphthalen‐2‐yl)prop‐2‐en‐1‐one (1) with hydrogen peroxide and reacted with different nucleophiles such as hydrazine hydrate, phenyl hydrazine, thiosemicarbazide to give 4‐hydroxy‐1H‐pyrazole derivatives 3a,b‐4. Also, compound 2 was treated with hydroxylamine hydrochloride to give the substituted 2,3‐dihydroisoxazole 5. Similarly, compound 2 was treated with carbon disulfide, phenyl isothiocyanate, and phenyl isocyanate to give the corresponding compounds 6–8. Various spectroscopic techniques and elemental analysis were used to determine the molecular structures of the new derivatives. All the new analogs were screened against five human pathogenic microbial strains: Escherichia coli and Pseudomonas aeruginosa as Gram‐negative bacteria, Bacillus subtilis and Staphylococcus aureus as Gram‐positive bacteria and the yeast Candida albicans using agar diffusion method. Compound 4 exhibited moderate antimicrobial activity against all the tested microorganisms compared to positive control ciprofloxacin and fluconazole. On the other hand, the free radical scavenging activity of the new compounds using DPPH assay protocol revealed that most of the compounds have a weak reducing activity. Moreover, compounds 4 and 8 were docked against 1KZN protein (DNA gyrase), 3FYV and 5V5Z showing the ability to interact with key amino acid residues and the potential to act as inhibitors.

Essential Oil Compositions and Antimicrobial Activities of Syzygium fluviatile (Hemsl.) Merr. & L.M.Perry: A Comparative Study on Collection Regions

Objective Essential oils extracted from Syzygium species are known for various pharmacological purposes. Syzygium fluviatile (Hemsl.) Merr. & L.M.Perry is a flowering plant found in China and Vietnam. The current study aims to offer a comparison of chemical compositions in essential oils of S. fluviatile fruits and leaves, collected from five regions of Vietnam. The obtained oils were also taken into antimicrobial consideration, which was further aided by in silico approaches. Methods Phytochemical analysis of essential oils was carried out using GC-FID/MS (gas chromatography-flame ionization detection/mass spectrometry) analysis. An antimicrobial assay was performed using broth micro-dilution for in vitro screening. In silico considerations are mainly based on docking studies and toxicity assessments using the AutoDock Vina v1.2.3 program and the ProTox 3.0 web server, respectively. Results Hydro-distillation of S. fluviatile fresh fruits and leaves can lead to the production of yellow essential oil with yields of 0.21–0.32% v/w. In general, the obtained oils were dominated by monoterpene and sesquiterpene derivatives, as well as ( E)-caryophyllene (8.40-47.12%) being the principal compound. The oil samples showed strong antimicrobial activity against the Gram (+) bacteria Enterococcus faecalis ATCC51299, Staphylococcus aureus ATCC29213, and Bacillus cereus ATCC11778, and the yeast Candida albicans ATCC 60193 with the MIC and IC50 values 16–64 µg/mL and 5.12–24.68 µg/mL. Docking results indicated that ( E)-caryophyllene exhibited binding affinities from −6.728 kcal/mol to −5.729 kcal/mol with important amino acid residues in the DNA gyrase, PBP3, and SAP2 targets. The toxicity profile of ( E)-caryophyllene is also discussed. Conclusion The isolation of ( E)-caryophyllene from Vietnamese Syzygium essential oils as a purified compound is necessary. In vivo antimicrobial studies and molecular mechanisms of action are needed.

Vaginal Yeast Infections: Causes, Symptoms, Diagnosis, and Treatment

Abstract Vaginal yeast infection, or vaginal candidiasis, is a common condition caused by the overgrowth of the yeast Candida albicans. Approximately 75% of women will experience at least one episode in their lifetime. Candida species, especially C. albicans, typically exist as part of the normal vaginal flora but can proliferate due to various triggers, such as antibiotic use, hormonal changes, or weakened immune systems. The infection presents with symptoms such as itching, burning, white discharge resembling cottage cheese, and discomfort during sexual intercourse. Diagnosis typically involves a pelvic examination, and treatment ranges from over-the-counter antifungal creams to prescription medications like fluconazole. Home remedies, such as applying yogurt or using probiotics, have gained popularity, though their efficacy is not consistently supported by clinical evidence. The potential complications of untreated infections include recurrent episodes, pelvic inflammatory disease, and in rare cases, increased susceptibility to sexually transmitted infections. Effective prevention strategies include avoiding douching, wearing breathable cotton underwear, and maintaining balanced vaginal flora. This communication focuses on the causes, symptoms, diagnosis, treatment, and preventive measures for vaginal yeast infection, emphasizing the need for accurate diagnosis and appropriate treatment to prevent recurrence and complications.