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Fungal infections are a global health problem with high mortality and morbidity rates. Available antifungal agents have high toxicity and pharmacodynamic and pharmacokinetic limitations. Moreover, the increased incidence of antifungal-resistant isolates and the emergence of intrinsically resistant species raise concerns about seeking alternatives for efficient antifungal therapy. In this context, we review literature data addressing the potential action of miltefosine (MFS), an anti- Leishmania and anticancer agent, as a repositioning drug for antifungal treatment. Here, we highlight the in vitro and in vivo data, MFS possible mechanisms of action, case reports, and nanocarrier-mediated MFS delivery, focusing on fungal infection therapy. Finally, many studies have demonstrated the promising antifungal action of MFS in vitro , but there is little or no data on antifungal activity in vertebrate animal models and clinical trials, so have a need to develop more research for the repositioning of MFS as an antifungal therapy. [ABSTRACT FROM AUTHOR]

Melanins are dark polymers found in the cell wall of pathogenic fungi, including species from the genus Sporothrix that are causative agents of sporotrichosis. In vitro experiments strongly suggest that these pigments are important for fungal virulence and survival in the host. In S. schenckii , melanin biosynthesis occurs via three different common pathways, which generate dihydroxynaphthalene (DHN)-melanin, DOPA-melanin or pyomelanin. Moreover, melanin biosynthesis can be enhanced when the fungus is in contact with some bacteria, such as Pseudomonas aeruginosa and Klebsiella pneumoniae . Melanin pigments have protective effects against antifungals in this genus. New scanning transmission electron tomography data indicates the accumulation of dark pigments in membrane-bound cytoplasmic organelles (melanosomes) in S. schenckii yeasts. Here, we provide an up to date of review the biosynthesis and role of melanins and discuss its roles on the cell biology and pathogenesis of Sporothrix spp. [ABSTRACT FROM AUTHOR]

Keratin proteins are a major constituent of skin and its appendages including nails, hair, feathers, and wool. Keratinases are peptidases that degrade keratin. Keratinases are produced by a number of different bacterial genera as well as dermatophyte fungi. The aim of this research was to isolate and identify keratinolytic yeasts that produce enzymes that might replace some of the chemicals used during tanning in leather production. Bioprospecting/sampling targeted discarded leather scraps from chromium-polluted soil adjacent to a tannery. Isolated yeasts were selected for identification and further characterization based on their ability to hydrolyze keratin and based on zymography analyses. Yeast strain RC-S6 was putatively identified as a Trichosporon loubieri strain based on biochemical and ribosomal DNA analyses. This strain produced its highest keratinase activity on nail keratin (193.3 U ml −1 ). Sulfide production was observed for all keratin media types but the best substrate was human hair. T. loubieri RC-S6 secretes keratinases that degrade nails, hair, feathers and wool and degradation was faster with nail and hair keratin. The keratinases from this strain have biotechnological potential for dehairing in leather production. [ABSTRACT FROM AUTHOR]

Castor seed cake, a solid residue produced after castor oil extraction, has been used as raw material in the pyrolysis process. Crude biochar (40.6% yield) was subjected to four activation methods; the best activating agent for obtaining activated biochar 1 (AB1) with 603.29 m2 g−1 of a specific area comparable to commercial active carbon in the methylene blue dye adsorption was concentrated sulfuric acid (H 2 SO 4). The adsorption experiments revealed the removal of more than 96% of the dye, kinetic studies showed that a pseudo-second-order (r2 ≥ 0.99) model fitted better with evaluated data and that intraparticle diffusion controls the adsorption rate of the dye by AB1. The aqueous phase (19.2% yield) was lyophilized, and the organic extract contains –N (3%), –O (49%), and –NO (48%) content compounds. The in vitro antifungal activity against the Cryptococcus species was evaluated, and a low concentration of the aqueous phase induced higher growth inhibition in C. neoformans and C. gattii. Therefore, the use of castor seed cake, an environmental waste, in the preparation of an adsorbent material can be considered a low-cost alternative for water treatment when contaminated with the MB dye. Moreover, the aqueous phase, which is a commonly neglected slow pyrolysis by-product, could be an efficient option for decontaminating areas with a high fungal load. ga1 • Biochar and aqueous phase were obtained from slow pyrolysis of castor seed cake. • Biochar was submitted to four different activation methods. • Biochar activated with H 2 SO 4 promoted an efficient adsorption of methylene blue dye. • Aqueous phase contains mainly N- and O-heterocycle compounds. • Aqueous phase was able to promote growth inhibition of C. neoformans and C. gatti. [ABSTRACT FROM AUTHOR]

Abstract: Two proteins from the eggshell of Rhodnius prolixus were isolated, characterized and named Rp30 and Rp45 according to their molecular masses. Purified proteins were used to obtain specific antiserum which was later used for immunolocalization. The antiserum against Rp30 and Rp45 detected their presence inside the follicle cells, their secretion and their association with oocyte microvilli. Both proteins are expressed during the final stage of vitellogenesis, preserved during embryogenesis and discarded together with the eggshell. The amino terminals were sequenced and both proteins were further cloned using degenerated primers. The amino acid sequences appear to have a tripartite arrangement with a highly conserved central domain which presents a repetitive motif of valine–proline–valine (VPV) at intervals of 15 amino acid residues. Their amino acid sequence showed no similarity to any known eggshell protein. The expression of these proteins was also investigated; the results demonstrated that this occurred strictly in choriogenic follicles. Antifungal activity against Aspergillus niger was found to be associated with Rp45 but not with Rp30. A. niger exposed to Rp45 protein induced growth inhibition and several morphological changes such as large vacuoles, swollen mitochondria, multi-lamellar structures and a disorganized cell wall as demonstrated by electron microscopy analysis. [Copyright &y& Elsevier]

Abstract: Pseudallescheria boydii is an emerging fungal pathogen that has a worldwide distribution. Virulence mechanisms of P. boydii are largely unknown. We studied the interaction between P. boydii and HEp2 cells and demonstrated that conidia of P. boydii attached to, and were ingested by, HEp2 cells in a time-dependent process. After 2 h of interaction, the conidia produced a germ-tube like projection, which was able to penetrate the epithelial cell membrane. Recently, our group characterized a peptidorhamnomannan (PRM) antigen on the cell surface of P. boydii. In order to better understand the role played by this surface glycoconjugate during cell adhesion and endocytosis, inhibition assays were performed using intact PRM and anti-PRM polyclonal antibody. When HEp2 cells were pre-treated with whole PRM molecule, the adhesion and endocytic indices were, respectively, 50% and 60% lower than in non-treated epithelial cells. Moreover, when the conidial cells were pre-incubated with anti-PRM antibodies, the adherence and endocytosis processes were inhibited in a dose-dependent manner. As PRM influenced the conidia P. boydii–HEp2 cell interaction, we also performed inhibition assays in order to observe which PRM moieties could be involved in this process. Treatment of PRM with proteinase K promoted a slight inhibition of adhesion. However, the de-O-glycosylated PRM molecule as well as the monosaccharide mannose was able to efficiently inhibit the adhesion and endocytic processes. In addition, our results indicate for the first time that P. boydii PRM binds to a polypeptide of 25 kDa on the HEp2 cell surface. [Copyright &y& Elsevier]

Development of effective strategies for treatment of candidiasis and other fungal diseases has posed a challenge, considering the increase in opportunistic fungal infections in HIV-positive and immunocompromised patients. The in vitro antifungal activity of essential oil from Ocimum gratissimum was investigated in order to evaluate its efficacy against Candida albicans, Candida krusei, Candida parapsilosis, and Candida tropicalis. Transmission and scanning electron microscopy and negative staining in light microscopy were performed to reveal the effects of the essential oil on the morphology of these yeasts. Determination of minimal inhibitory concentrations and time-kill curves demonstrated that the essential oil showed fungicidal activity against all of the Candida species studied. Analysis of the ultrastructure of the yeast cells revealed changes in the cell wall and in the morphology of some subcellular organelles. Bud formation in the yeasts was impaired in treated cells. The essential oil of O. gratissimum is a potential candidate as a phytotherapeutic agent in some fungal diseases and for the control of fungi in the environment. [Copyright &y& Elsevier]

In order to better understand the role played by surface glycoconjugates during host cell adhesion and endocytosis of Trichophyton rubrum, we looked for the presence of carbohydrate-binding adhesins on the microconidia surface and their role on cellular interaction with epithelial and macrophages cells. The interaction of T. rubrum with chinese hamster ovary epithelial cells and their glycosylation-deficient mutants demonstrated a higher adhesion index in Lec1 and Lec2 mutants, that express mannose and galactose, respectively. Endocytosed fungi were shown preferentially in Lec2 cells. Addition of the carbohydrates to the interaction medium, pretreatment with lectins and with sodium periodate decreased the adhesion and endocytic index for all mutants. The ability of the fungus to penetrate into mammalian cells was confirmed in experiments using macrophages treated with cytochalasin D. Flow cytometric analysis showed that this fungus recognizes mannose and galactose. The binding was inhibited by the addition of methyl α-d-mannopyranoside and methyl α-d-galactopyranoside, and showed higher fluorescence intensity at 37 than at 28 °C. Trypsin treatment and heating of the cells reduced the binding, suggesting a (glyco) protein nature for the microconidia adhesins. The presence of lectin-like molecules in fungus cell could be observed by scanning electron microscopy of the fungus incubated with colloidal-gold labeled neoglycoproteins. Our results suggest that T. rubrum has the ability to invade mammalian cells and expresses carbohydrate-specific adhesins on microconidia surface that recognize mannose and galactose. These adhesins may play an important role on the adhesion and invasion of the fungus during the infectious process of dermatophytosis. [Copyright &y& Elsevier]

The decoction of Cocos nucifera L. husk fiber has been used in northeastern Brazil traditional medicine for treatment of diarrhea and arthritis. Water extract obtained from coconut husk fiber and fractions from adsorption chromatography revealed antimicrobial activity against Staphylococcus aureus. The crude extract and one of the fractions rich in catechin also showed inhibitory activity against acyclovir-resistant herpes simplex virus type 1 (HSV-1-ACVr). All fractions were inactive against the fungi Candida albicans, Fonsecaea pedrosoi and Cryptococcus neoformans. Catechin and epicatechin together with condensed tannins (B-type procyanidins) were demonstrated to be the components of the water extract. [Copyright &y& Elsevier]

A series of new metal complexes, [Zn(KTZ) 2 (Ac) 2 ]·H 2 O (1) , [Zn(KTZ) 2 Cl 2 ]·0.4CH 3 OH (2), [Zn(KTZ) 2 (H 2 O)(NO 3)](NO 3) (3), [Cu(KTZ) 2 (Ac) 2 ]·H 2 O (4) , [Cu(KTZ) 2 Cl 2 ]·3.2H 2 O (5), [Cu(KTZ) 2 (H 2 O)(NO 3)](NO 3)·H 2 O (6), were synthesized by a reaction of ketoconazole (KTZ) with their respective zinc or copper salts under mild conditions. Similarly, six corresponding metal-CTZ (clotrimazole) complexes [Zn(CTZ) 2 (Ac) 2 ]·4H 2 O (7) , [Zn(CTZ) 2 Cl 2 ] (8), [Zn(CTZ) 2 (H 2 O)(NO 3)](NO 3)·4H 2 O (9), [Cu(CTZ) 2 (Ac) 2 ]·H 2 O (10) , [Cu(CTZ) 2 Cl 2 ]·2H 2 O (11), [Cu(CTZ) 2 (H 2 O)(NO 3)](NO 3)·2H 2 O (12), were obtained. These metal complexes were characterized by elemental analyses, molar conductivity, 1H and 13C{1H} nuclear magnetic resonance, UV/Vis, and infrared spectroscopies. Further, the crystal structure for complexes 7 and 10 was determined by single-crystal X-ray diffraction. The antifungal activity of these metal complexes was evaluated against three fungal species of medical relevance: Candida albicans , Cryptococcus neoformans, and Sporothrix brasiliensis. Complexes 1 and 3 exhibited the greatest antifungal activity with a broad spectrum of action at low concentrations and high selectivity. Some morphological changes induced by these metal complexes in S. brasiliensis cells included yeast-hyphae conversion, an increase in cell size and cell wall damage. The strategy of coordination of clinic drugs (KTZ and CTZ) to zinc and copper was successful, since the corresponding metal complexes were more effective than the parent drug. Particularly, the promising antifungal activities displayed by Zn-KTZ complexes make them potential candidates for the development of an alternative drug to treat mycoses. A series of new Zn(II)/Cu(II)- azole drug complexes were synthesized, characterized and evaluated against three fungal species of medical relevance: Candida albicans , Cryptococcus neoformans, and Sporothrix brasiliensis. Zn(II)-KTZ (KTZ: Ketoconazole) complexes exhibited the greatest antifungal activity with a broad spectrum of action at low concentrations and high selectivity. [Display omitted] • Ten novel Zn(II)/Cu(II)-azole drug complexes were synthesized. • X-ray structure of two Zn(II)/Cu(II)-CTZ (CTZ: Clotrimazole) complexes were elucidated. • They were evaluated against three fungal species of medical relevance. • Zn(II)-KTZ (KTZ: Ketozonazole) complexes were the most effective antifungal agents. • They displayed high selectivity towards fungi over mammalian cells. [ABSTRACT FROM AUTHOR]