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The increasing severity of fungal infections globally and the limited availability of effective treatments necessitate novel therapeutic strategies. In this study, we prepared copper‐polyphenol nanocomplexes (CPE NPs) through a one‐step synthetic process by the coordination self‐assembly of copper sulfate (CuSO4), protocatechuic acid (PA), and ϵ‐poly‐L‐lysine (EPL). CPE NPs demonstrated peroxidase‐like activities, which could catalyze H2O2 to generate hydroxyl radicals (⋅OH) to effectively eradicate fungi. CPE NPs were stable in a physiological neutral environment. However, since metal‐phenolic coordination interaction was unstable in acidic pH, CPE NPs could be dissociated in acidic environments, such as fungal infection sites, leading to effective release of Cu2+ and EPL, thereby exerting antifungal effects. CPE NPs exhibited excellent fungicidal ability at both pH 7.4 and 6.0 against Candida albicans and Aspergillus flavus. More importantly, CPE NPs could effectively eradicate fungi in 20 % Sabouraud dextrose broth (SDB) medium containing rich inorganic salts and proteins, in which dissociative Cu2+ completely lost its fungicidal ability. In summary, CPE NPs could effectively deliver Cu2+ to fungal surface for enhanced fungal eradication by generating ⋅OH, highlighting their great potential as a promising nano‐therapeutic agent for the treatment of fungal infections. [ABSTRACT FROM AUTHOR]

Pesticides are indispensable in agricultural development, but their effectiveness is often hindered by natural factors like rain‐off and degradation. Herein, tebuconazole nanopesticides (TEB NPs) with leaf‐adhesive, water‐stable, and small‐sized were successfully prepared by flash nanoprecipitation using the biodegradable polyethylene glycol‐b‐poly (lactic‐co‐glycolic acid) as a carrier. The nanopesticides could be efficiently deposited on plant leaves with uniform distribution and exhibited a 14° lower contact angle with foliage compared to commercial suspensions. The encapsulation of TEB within the polymer enhanced its resistance to photolysis, resulting in a 5‐h extension of its half‐life. TEB NPs were readily taken up by fungi and plants, thereby enhancing fungicidal efficacy. This nanopesticide could achieve the desired antifungal effect with reduced dosage and improved pesticide utilization. Therefore, the work is expected to provide a simple nanoplatform for improving pesticide utilization and promoting green agriculture. [ABSTRACT FROM AUTHOR]

The present study focuses on the evaluation of the DNA and BSA binding capability, anti‐fungal, metal chelation, and larvicidal activity of extracts of Azadirachta indica A Juss flower. The different extracts of A. indica was prepared by soxhlet extraction using Petroleum Ether (PE), acetone (AC), and hydroalcohol (HA) as solvents. DNA and BSA binding ability of HA extract was calculated through the UV–Visible titrimetric method. The phytochemicals present in the extract show good binding ability towards DNA and BSA. H2O2 and NO scavenging activity were evaluated and HA extracts shows good antioxidant activity with IC50 values of 62 and 48 μg/mg, respectively. The metal chelating property was calculated, where HA shows good chelating ability with the IC50 value of 32.23 μg/mg. The antifungal activity of these extracts was evaluated against different fungal stains; among them, hydroalcoholic extract shows a higher zone of inhibition in all the fungal stains than Petroleum Ether and acetone extracts and acetone extracts (i.e., 50 μg/μL MIC). The potential extract (i.e., HA extract) was used to estimate the larvicidal activity of parasites. The % of mortality was evaluated through a dose‐dependent assay and it is confirmed that when concentration increases, the mortality rate increases. The correlation between metal chelating activity and total flavonoid and phenolic content was calculated and it was found that there is a good correlation (R2 –.743 and.902, respectively). These results proved that HA extract possesses biologically important phytochemicals that contribute to pharmaceutical and biological activities and could be a natural remedy for various real‐time applications. [ABSTRACT FROM AUTHOR]

Background: Amphotericin‐B (AmB) is an essential medication for the treatment of life‐threatening systemic mycoses but the incidence and risk factors for acute kidney injury (AKI) after its administration are not known in dogs. Objective: Determine the incidence of and risk factors for AKI in dogs receiving AmB. Animals: Fifty‐one client owned dogs receiving AmB for the treatment of systemic mycoses. Methods: Retrospective study. Signalment, potential risk factors, AKI development (creatinine ≥0.3 mg/dL from baseline), drug formulation (deoxycholate [AmB‐D] or lipid complex [ABLC]), dose, and treatment duration were recorded. The probability of an AKI diagnosis was evaluated using a log‐rank test. The incidence of AKI and odds ratios were calculated for potential risk factors. Results: Incidence of AKI was 5/12 (42%) for dogs receiving AmB‐D and 14/39 (36%) for dogs receiving ABLC. Of the 19 dogs that developed AKI, 16 (84%) continued treatment after a pause in the planned dosing protocol. Fifty percent of dogs received a cumulative dose of 6.9 mg/kg for AmB‐D and 22.5 mg/kg for ABLC (P <.01) at time of AKI diagnosis. ICU hospitalization (odds ratio [OR] 0.21, 95% confidence interval [CI]: 0.58‐0.87) and inpatient status (OR 0.25, 95% CI: 0.07‐0.86) were associated with decreased odds of AKI. Conclusions and Clinical Importance: Incidence of AKI with AmB is common but does not always preclude continued treatment. The incidence of AKI is similar between AmB‐D and ABLC, but dogs receiving ABLC tolerated a higher cumulative total dose before AKI diagnosis. [ABSTRACT FROM AUTHOR]

BACKGROUND Cucumber downy mildew (CDM) is a severe plant disease and affects the yield of cucumber production worldwide. As the resistance toward conventional fungicides is emerging as a ubiquitous issue, it is urgent to discover efficient fungicides with unique structures. RESULTS: In this study, a series of novel phenylpyridine derivatives were designed and synthesized. Bioassays revealed that most of these compounds possessed excellent fungicidal activities against CDM. Among the phenylpyridine compounds, 2‐(4‐(4‐(tert‐butyl)benzyl)piperazin‐1‐yl)‐6‐phenylnicotinonitrile (C8) [half‐maximal effective concentration (EC50) = 4.40 mg L−1] displayed the highest activity, which was better than those of the commercial fungicides, such as azoxystrobin (EC50 = 42.77 mg L−1) and flumorph (EC50 = 41.94 mg L−1). Furthermore, the molecular electrostatic potential of high‐activity compound C8 indicated that nitrogen atom of the cyano group on the pyridine ring was in the negative region and may easily form hydrogen bonds and allow for electrostatic interactions with potential receptors. CONCLUSIONS: This study demonstrated that the novel N‐substituted piperazine‐containing phenylpyridine derivatives could be further developed as a candidate compound to control CDM. [ABSTRACT FROM AUTHOR]

A 6‐year‐old male leopard gecko (Eublepharis macularius) was presented with a 2‐year history of recurrent dysecdysis involving the ocular surface of both eyes. Ophthalmic examination revealed ocular surface desiccation and multifocal superficial ulcerative keratitis with patchy remnants of retained shed. Other abnormalities included stomatitis and mandibular and maxillary osteomyelitis. Topical and systemic antibiotic therapy, oral vitamin A, and improved husbandry conditions resolved the stomatitis and osteomyelitis but did not improve the ocular surface. Corneal cytology collected with a cytobrush revealed branching hyphae and budding yeast consistent with fungal keratitis. Fungal culture grew Acremonium sp. and Trichosporon sp. The addition of topical antifungal therapy improved the ocular surface health, but the patient was euthanized 7 weeks after initial presentation for persistent vomiting and dyspnea. Necropsy was declined. This case describes the first case of fungal keratitis caused by Acremonium sp. and Trichosporon sp. in a reptile. [ABSTRACT FROM AUTHOR]

The amino acid derivative 2-hydroxyisocaproic acid (HICA) is a nutritional additive used to increase muscle mass. Low levels can be detected in human plasma as a result of leucine metabolism. It has broad antibacterial activity but its efficacy against pathogenic fungi is not known. The aim was to test the efficacy of HICA against Candida and Aspergillus species. Efficacy of HICA against 19 clinical and reference isolates representing five Candida and three Aspergillus species with variable azole antifungal sensitivity profiles was tested using a microdilution method. The concentrations were 18, 36 and 72 mg ml−1. Growth was determined spectrophotometrically for Candida isolates and by visual inspection for Aspergillus isolates, viability was tested by culture and impact on morphology by microscopy. HICA of 72 mg ml−1 was fungicidal against all Candida and Aspergillus fumigatus and Aspergillus terreus isolates. Lower concentrations were fungistatic. Aspergillus flavus was not inhibited by HICA. HICA inhibited hyphal formation in susceptible Candida albicans and A. fumigatus isolates and affected cell wall integrity. In conclusion, HICA has broad antifungal activity against Candida and Aspergillus at concentrations relevant for topical therapy. As a fungicidal agent with broad-spectrum bactericidal activity, it may be useful in the topical treatment of multispecies superficial infections. [ABSTRACT FROM AUTHOR]

Background Pediococcus acidilactici LAB 5 produces an antifungal compound under in vitro conditions in an inducer-dependent manner. The main objective of the present study was to partially characterise this antifungal compound by UV-visible, IR, 1H NMR, 13C NMR and GC/ MS analyses and also to assess its potentiality against a number of food spoilage, plant-pathogenic and human-pathogenic fungal species. Results The strain produced a broad-spectrum antifungal compound(s) that was induced by certain constituent factors of MRS and malt extract media. The production was higher in solid culture than in broth culture. The product was found to be a mixture of lactic acid and a compound of molecular mass 83. The minimum inhibitory concentrations ( MIC90, 1.32-2.86 g L−1) of the active extract were much lower than those of sodium benzoate and calcium propionate. Scanning electron micrographs proved its drastic action on the development of conidial structures. Conclusion The chemical analysis indicated a novel compound with fungicidal activity. This compound could be used in fermented foods and feeds to extend their shelf life and also in agricultural crop plants against certain fungal pathogens. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The fungicidal properties of purified CAY-1, dissolved silver ion and ethylenediamine tetraacetic acid (EDTA) separately were studied in vitro as were the abilities of silver and EDTA to enhance CAY-1 fungicidal properties. Non-germinated and germinating conidia of Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Fusarium verticillioides ( Fusarium moniliforme), Fusarium oxysporum and Fusarium solani were incubated separately with CAY-1 (0-24.8 μg ml), silver (0-111.1 μg ml), and EDTA (0-2400 μg ml). Controls consisted of non-germinated or germinated conidia in test medium. To assess combined activity, compounds, based on the sub-lethal doses of each as defined in the initial experiments, were combined and tested in bioassays. Controls for the mixed sets consisted of non-germinated or germinated conidia only or with the sub-lethal CAY-1 test concentrations. The minimum inhibitory concentrations (MICs) for CAY-1 and silver, both separate and combined, were determined. Viability assays showed CAY-1 activity only against the germinating conidia of A. flavus, A. niger and F. solani. Silver was active against the germinating conidia of all fungi and the non-germinated conidia of F. oxysporum and F. solani. Combined silver and CAY-1 produced significant viability loss at concentrations not effective separately. EDTA was not fungicidal separately and did not enhance CAY-1 fungicidal properties. MIC data showed that CAY-1 plus silver had an additive effect. Results indicate that dissolved silver was fungicidal in vitro and enhanced the fungicidal properties of CAY-1 at concentrations ineffective when tested separately. [ABSTRACT FROM AUTHOR]

Candida dubliniensis is a recently described yeast that causes infections in mucosal surfaces as well as sterile body sites. Candida dubliniensis develops resistance to fluconazole (FLC) more rapidly than the closely related species C. albicans. The killing activity of amphotericin B (AMB), 5-fluorocytosine (5FC), FLC, voriconazole (VRC) and posaconazole (POS) was determined against six C. dubliniensis clinical isolates, identified using molecular biological methods and C. dubliniensis CD36 reference strain. Minimum inhibitory concentrations (MICs) were determined using the Clinical and Laboratory Standards Institute standard procedure. Time-kill assays were performed using RPMI-1640 as test media over a 48-h period. AMB proved to be fungicidal at ≥0.5 μg ml−1 against all clinical isolates after 48 h. 5FC was only fungicidal at 32–64× MIC (4–8 μg ml−1) against all C. dubliniensis isolates . FLC, VRC and POS were fungistatic; decrease in colony number was observed only at the highest concentrations tested (8, 4 and 4 μg ml−1, respectively). Triazoles invariably showed fungistatic effect at concentrations attainable in the serum. In clinical situations when a fungicidal antifungal is desirable, AMB may be used. [ABSTRACT FROM AUTHOR]

Two series of gemini cationic surfactants were synthesized based on glucose and fructose molecules. Their chemical structures were confirmed using micro-elemental analysis, mass spectral fragmentation and FTIR spectroscopic analysis. The surface activities of these gemini amphiphiles were measured, including surface tension ( γ), critical micelle concentration (CMC), effectiveness ( π cmc), efficiency (pC20), maximum surface excess (Γmax) and minimum surface area ( A min) at 25 °C. Adsorption and micellization free energies of these amphiphiles in their solutions showed a good tendency towards adsorption at the interfaces. The biological activity of the synthesized gemini amphiphiles showed good inhibition at concentrations of 1, 2.5 and 5 mg/mL. The synthesized amphiphiles showed antimicrobial activity on gram-positive and gram-negative bacteria and antifungal activity equal to or comparable to commercially available controls. The discussion rationalized the antimicrobial activities of these amphiphiles with the surface activity and the adsorption parameters. In addition, the effect of sugar nuclei was discussed based on the chemical structure of the bacterial and fungal cell membranes. [ABSTRACT FROM AUTHOR]

Abstract This study aimed at examining the effects of the saturated fatty acid lauric acid on mycelial growth of Rhizoctonia solani and Pythium ultimum and on infection of barley seedlings with Blumeria graminis f. sp. hordei . Mycelial growth of R. solani and P. ultimum in agar culture was significantly reduced by lauric acid at concentrations of 100 μm and above, while no fungal growth occurred in liquid culture at concentrations above 50 μm. Application of lauric acid at concentrations ranging from 250 to 1000 μm to barley leaves before or after inoculation with B. graminis f. sp. hordei led to significant reductions in infection. This study provides the first report of the activity of lauric acid against plant pathogenic fungi and indicates the need for investigation of its mechanism of action. [ABSTRACT FROM AUTHOR]