Investigation of powerful fungicidal activity of tetra-cationic platinum(II) and palladium(II) porphyrins by antimicrobial photodynamic therapy assays

This manuscript reports enhanced antimicrobial photoinactivation using tetra-cationic porphyrins with peripheral platinum(II) and palladium(II) complexes against fungal dermatophyte strains. Six different positively charged porphyrins were used and applied in antimicrobial photodynamic therapy experiments (aPDT) against dermatophyte fungi colonies. The microbiological tests were conducted with an adequate concentration of photosensitizer (PS) under white-light irradiation for 120 min and the most effective PS meta isomer 3PtP significantly reduced the concentration of viable fungal colony. In this way, tetra-cationic porphyrins containing platinum(II)-bipyridyl complexes may be promising fungicidal aPDT agents with potential applications in future clinical cases.

Short communication: Algicide activity of antimicrobial peptides compounds against Prototheca bovis

This study evaluated the in vitro activity of antimicrobial peptides pexiganan (MSI-78), h-Lf1-11, LL-37, cecropin B, magainin-2, and fengycin B against the veterinary mastitis agent Prototheca bovis. The results showed that pexiganan, h-Lf1-11, LL-37, and cecropin B were able to inhibit the growth and had effect on algicide P. bovis isolates (n = 32). The minimum inhibitory concentration ranged from 5 to 10 µg/mL for pexiganan, and algicide effect was detected from 5 to 20 µg/mL. The minimum inhibitory concentration ranged from 10 to 80 µg/mL for h-Lf1-11, 20 to 80 µg/mL for LL-37, and 40 to 160 µg/mL for cecropin B. These findings present a promising and novel alternative for P. bovis treatment and growth control.

Novel Alkyl(aryl)-Substituted 2,2-Difluoro-6-(trichloromethyl)-2H-1,3,2-oxazaborinin-3-ium-2-uides: Synthesis, Antimicrobial Activity, and CT-DNA Binding Evaluations

The synthesis, antimicrobial activity evaluations, biomolecule-binding properties (DNA), and absorption and emission properties of a new series of (Z)-1,1,1-trichloro-4-alkyl(aryl)amino-4-arylbut-3-en-2-ones (4, 5) and 2,2-difluoro-3-alkyl(aryl)amino-4-aryl-6-(trichloromethyl)-2H-1,3,2-oxazaborinin-3-ium-2-uides (6, 7) in which 3(4)-alkyl(aryl) = H, Me, iso-propyl, n-butyl, C6H5, 4-CH3C6H4, 4-CH3OC6H4, 4-NO2C6H4, 4-FC6H4, 4-BrC6H4, 2-naphthyl, is reported. A series of β-enaminoketones (4, 5) is synthesized from the O,N-exchange reaction of some amines (3) with (Z)-1,1,1-trichloro-4-methoxy-4-aryl-but-3-en-2-ones (1, 2) at 61-90% yields. Subsequently, reactions of the resulting β-enaminoketones with an appropriate source of boron (BF3.OEt2) gave the corresponding oxazaborinine derivatives (6, 7) at 50-91% yields. UV-Vis and emission properties of biomolecule-binding properties for the DNA of these new BF2-β-enamino containing CCl3 units were also evaluated. Some compounds from the present series also exhibited potent antimicrobial effects on various pathogenic microorganisms at concentrations below those that showed cytotoxic effects. Compounds 4d, 4e, 6e, and 6f showed the best results and are very significant against P. zopfii, which causes diseases in humans and animals.

Antifungal susceptibility profile of Aspergillus fumigatus isolates from avian lungs

ABSTRACT: Susceptibility testing is essential to inform the correct management of Aspergillus infections. In this study we present antifungal susceptibility profile of A. fumigatus isolates recovered from lungs of birds with and without aspergillosis. Fifty three isolates were tested for their antifungal susceptibility to voriconazole (VRC), itraconazole (ITZ), amphotericin (AMB) and caspofungin (CSP) using the M38-A2 broth microdilution reference method. Five isolates were resistant to more than one antifungal drug (CSP + AMB, VRC + ITZ and AMB + ITZ). Fifteen (28%) isolates with susceptible increased exposure (I) to ITZ were sensible to VRC. Resistance to AMB (>2μg/mL) was observed in only four isolates. Eleven (21%) A. fumigatus present resistance to ITZ (13%) and VRC (8%). Fungal isolation from respiratory samples has been regarded as being of limited usefulness in the ante mortem diagnosis of aspergillosis in birds. However, the results suggest that the detection and antifungal susceptibility profile may be helpful for monitoring of therapy for avian species and where antifungal resistance might be emerging and what conditions are associated to the event.

Formulation and in vitro evaluation of coconut oil-core cationic nanocapsules intended for vaginal delivery of clotrimazole

The objective of this work was to propose coconut oil-core nanocapsules prepared from Eudragit(®) RS100, a cationic polymer, and to evaluate their potential for vaginal delivery of clotrimazole in candidiasis. Nanocapsule suspensions loaded with clotrimazole at 1.0 and 3.0mg/mL were prepared by interfacial deposition of Eudragit(®) RS100. The physicochemical characterization showed average diameter lower than 200 nm, low polydispersity index, positive zeta potential (+10.94 to +14.57 mV), acid pH values (5.4-5.7) and encapsulation efficiencies close to 100%. After 60 days of storage at room temperature and protected from light, the nanocapsules were reasonably stable. Photodegradation studies showed that nanoencapsulation improved clotrimazole stability against UV radiation. The in vitro drug release at pH 4.5 was characterized by a prolonged release with no burst effect. The nanocapsules were more active than free clotrimazole against Candida albicans and Candida glabrata strains susceptible and resistant to fluconazole. Hence, clotrimazole-loaded coconut oil-core nanocapsules represent promising alternatives to the treatment of vulvovaginal candidiasis.