The objective of this study was to evaluate the effects of nanoparticles (nanospheres and nanocapsules) of the promising antifungal 2-amino-thiophene (6CN10) and 6CN10 complexed with 2-hydroxypropyl-β-cyclodextrin (6CN10:HP-β-CD) in vitro and compared with free drug against Candida and Cryptococcus, using a microdilution method to measure susceptibility. The Candida and Cryptococcus clinical strains were identified using phenotypic methods and matrix-assisted laser desorption/ ionization-time of flight (MALDI-TOF). To measure in vitro antifungal susceptibility, we used microdilution trials. Serial drug or nanoparticle dilutions were prepared according to the CLSI M27-A3 guidelines. Anti-biofilm activity was verified for Cryptococcus neoformans. All Candida isolates were sensitive to the free drug (MIC = 41.66-333.33 μg/mL) and were able to grow even at the higher concentration tested for all 6CN10 nanoparticles. However, the Cryptococcus neoformans strains presented MIC values of 0.32-83.33 μg/mL for 6CN10 nanoparticles, and MIC values of 0.1-0.2 μg/mL for 6CN10:HP-β-CD nanoparticles, i.e., 3333 times more active than the free drug (MIC values 166.66-333.33 μg/mL), and presenting activity greater than that of the reference drug amphotericin B (MIC = 0.5-0.125 μg/mL). 6CN10:HP-β-CD nanosphere also showed high antibiofilm potential. The in vitro study showed that the nanoparticles allowed better drug efficiency against Cryptococcus than did the free drug. These results suggest that 6CN10-loaded nanoparticles may become a future alternative for cryptococcosis and candidiasis therapy. In vivo experiments are essential prior to clinical use.

Pyocyanin is a pigment produced by 95% of Pseudomonas aeruginosa strains and exhibits antimicrobial properties that can be used for different purposes. In this work, PMMA-based nanoparticles that were encapsulated into 200 µg/mL of pyocyanin (Np-Pyo) were produced by the nanoprecipitation method. They were evaluated with respect to antifouling activity against Aspergillus sp. and Penicillium sp. With an encapsulation efficiency of 56%, the NpPyo remained stable for 90 days. Their characteristics were satisfactory for the following parameters: average size (616.90±38.30 nm; blank: 282.58±22.89 nm), polydispersion index (0.51±0.01; blank: 0.45±0.78), zeta potential (-5.13±0.41 mV; blank: -6.44±1.12 mV) and pH (6.18±0.03; blank: 6.42±0.01). The in vitro biofilm formation assay was performed on dolomite coupons measuring 1 cm2, on which the formulation was applied. There were tested conditions with and without immersion for 72h at 30 ºC. In the tests with the immersed coupons, there was fungal colonization; this was, however, lower than that observed in the control. A. niger decreased by 3 log units. No growth was observed on the coupons that were not immersed. The results were promising and demonstrated viability as a means of antifouling protection, particularly on dry surfaces.

A pele é um revelador do envelhecimento saudável, em que diversos recursos buscam desacelerar a sua senescência e impedir os danos causados pelos fatores extrínsecos. A curcumina, composto ativo da Curcuma longa L., vem sendo estudada como um possível adjuvante antienvelhecimento, por apresentar propriedades funcionais, em principal, as atividades antioxidantes e anti-inflamatórias. Entretanto, a sua instabilidade química e biodisponibilidade dificultam a sua utilização. Neste contexto, pesquisas vêm sendo realizadas com o propósito de encapsular a cúrcuma em nanoestruturas. O objetivo desta revisão é atrelar o potencial da curcumina no processo de envelhecimento cutâneo às abordagens que utilizam a nanotecnologia, através de nanoestruturas lipídicas, a fim de melhorar sua aplicabilidade no uso tópico. Para obtenção dos dados, foi realizada uma pesquisa qualitativa através de uma busca sistemática utilizando os bancos de dados Google Acadêmico, Web of Science e Pubmed com diferentes combinações de palavras-chaves. Apesar de inúmeros estudos correlacionando a curcumina e a nanotecnologia, neste trabalho foi possível observar a escassez de resultados que trazem a participação desta substância no processo de envelhecimento, sendo necessária uma maior exploração por meio de pesquisas, tendo em vista o grande interesse comercial da curcumina para o desenvolvimento racional de fármacos.

Pyocyanin is an active redox phenazine of intense blue color and specific to Pseudomonas aeruginosa. The synthesis of the molecule confers different benefits to the bacterium. Pyocyanin can control its growth and persistence in environments with high nutritional pressures, forming biofilms. As well, synthesis of pyocyanin enables P. aeruginosa tolerate and uptake highly toxic compounds such as polycyclic aromatic hydrocarbons (PAHs), considered the most dangerous compounds among all molecules found in crude oil and petroderivatives. Additionally, pyocyanin increases the bioavailability of PAHs and its metabolites are used to synthetize crucial molecules for the biodegradation of other PAHs. On the other hand, oil hydrocarbons can serve as oxygen vectors during the synthesis of pyocyanin, contributing to the sustainability of the biodegradation process. This review is a compilation of recent advances reported in the literature about the relationship between pyocyanin expression and the hydrocarbonoclastic activity of P. aeruginosa. This characteristic, for the pyocyanin-deficient strains, is important for the degradation of PAHs, a topic that has been unevenly studied.

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