Biogenic silver nanoparticles are synthesized through silver(I) reduction, which is promoted by biomolecules available in the biological world and mostly obtained from plant extracts, fungal bioproduction, and some bacteria. The exact mechanisms accounting for such oxidoreduction processes are not fully known. However, some studies have already mentioned oxidoreductases, cofactors (nicotinamide adenine dinucelotide hydrogen (NADH), dihydroflavine-adenine dinucleotid (FADH2)), and phenolic compounds, as the main reductive species engaged in the formation of silver(0) and silver nanoparticles (silver NPs) synthesis. Biosynthesis is a one-pot process that leads to stable silver NP colloids that, regarding their size, shape, and uniformity, can be successfully controlled; and show great stability when one takes into account their surface capping by some biomolecules that as well take part in their synthesis. Although great efforts have been made to feature capping biomolecules and their interactions with silver NP surfaces, knowledge of the quantity (exact number per cm2) and type of biomolecules that cap or surround silver NPs remains limited. The literature provides detailed information on protein capping, but it still shows gaps regarding many aspects of fine biophysical protein featuring. The reason why certain proteins prefer to interact with silver NP surface and form chemical bonds, whereas others rather have intermolecular interaction with the first layer of proteins remains unknown. Assessing capping proteins’ involvement in the bioactivity of biogenic silver NPs is another relevant research field. Certain proteins enhance bioactivity of silver NPs and lower toxicity; however, the way antimicrobial processes benefit from protein capping is yet to be discovered. Finally, biogenic silver NPs can be found both in the environment and in water; moreover, their additional activity and behavior must be known or, at least, hypothesized.

To improve 17-α-estradiol targeting in alopecia treatment, a formulation of nanostructured lipid carrier (NLC) prepared by the sonication method was developed. The physicochemical characterization showed an average diameter of 96 ± 15 nm and the average zeta potential of -17 ± 6 mV. In addition, the encapsulation efficiency (EE) of 17-α-estradiol, assessed by ultra-performance liquid chromatography (UPLC) fluorescence, was 99.6 ± 0.3%. Physical stability of NLC stored at room temperature was followed for 42 days through several physicochemical parameters, such as diameter, zeta potential, pH and EE. No changes were observed in the physicochemical parameters during this period, demonstrating the potential of NLC as a delivery system of 17-α-estradiol. NLC dermal penetration, investigated by Franz diffusion cell and confocal microscopy using rhodamine-labeled NLCs, showed an accumulation of NLC in the outer portions of the epidermis, precisely in the hair follicle. The NLCs distribution in the skin suggests that 17-α-estradiol targeting was improved.

Many well-known commercial pharmaceuticals have been used in the therapy against SARS-CoV-2, although in a random and experimental way, since this use is only based on the knowledge about culture cells in vitro. But, it is widely known that it is not correlated with assays in vivo conducted with in animals or with clinical trials in humans. Knowledge about treatments applied to previous pandemic infections caused by viruses such as MERS and SARS may be the most interesting strategy used to screen products with potential to act against SARS-CoV-2. Mechanistic aspects of virus infections and antiviral action mechanisms were herein analyzed based on the assumption that these commercial pharmaceuticals can eliminate the virus. Perspectives about these procedures, as well as about finished clinical trials and the ones yet in progress, were also addressed in the current study.

Muchos productos farmacéuticos comerciales bien conocidos se han utilizado en la terapia contra el SARS-CoV-2, aunque de manera aleatoria y experimental, ya que este uso solo se basa en el conocimiento sobre células de cultivo in vitro. Pero, es ampliamente conocido que no está correlacionado con ensayos in vivo realizados con animales o con ensayos clínicos en humanos. El conocimiento sobre los tratamientos aplicados a infecciones pandémicas previas causadas por virus como MERS y SARS puede ser la estrategia más interesante utilizada para detectar productos con potencial para actuar contra el SARS-CoV-2. Los aspectos mecanicistas de las infecciones por virus y los mecanismos de acción antivirales se analizaron en este documento basándose en el supuesto de que estos productos farmacéuticos comerciales pueden eliminar el virus. Las perspectivas sobre estos procedimientos, así como sobre los ensayos clínicos terminados y los que aún están en progreso, también se abordaron en el estudio actual.

Muitos fármacos comerciais bem conhecidos têm sido utilizados na terapia contra SARS-CoV-2, embora de maneira aleatória e experimental, uma vez que esse uso é baseado apenas no conhecimento sobre cultura de células in vitro. Entretanto, sabe-se o que não está correlacionado com ensaios in vivo realizados com animais ou com ensaios clínicos em humanos. O conhecimento sobre tratamentos aplicados a infecções pandêmicas anteriores causadas por vírus como MERS e SARS pode ser a estratégia mais interessante usada para rastrear produtos com potencial para agir contra o SARS-CoV-2. Aspectos mecanísticos de infecções por vírus e mecanismos de ação antiviral foram aqui analisados com base no pressuposto de que esses produtos farmacêuticos comerciais podem eliminar o vírus. As perspectivas sobre esses procedimentos, bem como sobre os ensaios clínicos concluídos e os que ainda estão em andamento, também foram abordados no presente estudo.

Silver nanoparticles (AgNPs) have important antimicrobial activity. These nanoparticles are present in several commercial products, leading to human and environmental exposure. This review presents a critical view of the toxic effects of Ag NPs on in vitro and in vivo biological models. It is noteworthy that the toxicity of AgNPs is dependent on several parameters, such as the preparation mode of the colloidal suspension of the nanoparticles, their state of aggregation, the chemical nature of the nanoparticles, surface size, morphology, dose, cell type, nature of the living organism, among others. In general, low concentrations of AgNPs do not present significant toxicity in in vitro and in vivo assays, however with the increase of the concentration of AgNPs there is a significant increase of nanoparticle toxicity and its accumulation in diverse tissues/organs. It should be emphasized that in living organisms, exposure routes should be taken into account, such as ingestion and inhalation. At high concentrations, inhalation or ingestion of AgNPs can cause adverse effects and even lead to human death. In this context, the importance of further studies of the toxicity of AgNPs in several in vitro and in vivo models is emphasized.

The ecological processes in which metabolites with industrial or medical applications are produced are of great importance. Magnesium plays many important roles in environmental and medical applications. Phosphorus is obtained by mining. It is estimated to have a very limited half-life and expected to be depleted as a resource in 100 years. Its recovery by mining and subsequent marketing as phosphate has important environmental implications. These processes are part of an important recovery technology. Bacteria have contributed to the formation of minerals since the advent of life on Earth. Bacterial and/or fungal biomineralizations play a critical role in biogeochemical cycles. These processes have important technological and environmental applications. In many past publications dealing with bacterial and fungal recovery of phosphates as insoluble products, magnesium played an important role. This is a review of recent progress in the microbial recovery of biogenic magnesium phosphate compounds, their importance, and their roles in treatment of several human diseases.

The primary treatment for high-grade non-muscle invasive bladder cancer (NMIBC) is based on surgery by transurethral resection of bladder tumor (TURBT), followed by intravesical immunotherapy with Bacillus Calmette-Guerin (BCG) to prevent recurrence and to reduce the tumor progression. However, BCG therapy shows several undesirable effects. The current treatment on NMIBC is doxorubicin (DOX), but with high toxicity. Our nanotechnology strategy was done through scaffolds for the NMIBC treatment: graphene oxide (GO) and a nanostructured lipid carrier (NLC). A GO hybrid for administration of DOX and small interfering RNA (siRNA) was developed. This hybrids administered in vivo against NMIBC in rats gave absence of lesions. NLC was prepared by using a mixture of two lipids stabilized by a surfactant and DOX by high homogenization pressure technique. In this case showed a 20% of the animals exhibited benign lesions (papillary hyperplasia), however, in the presence of siRNA reached 40% of rats with benignant lesions. These two scaffolds are potential new drugs for DOX for bladder cancer treatment without any cardiotoxicity problems.

This overview highlights the importance of characterization of biogenic nanoparticles of silver and silver chloride in order to understand the action on ticks or pathogens transmitted by them. These nanoparticles appear as important active principles in this area. They can act against ticks or against major pathogens transmitted by the bite of ticks such as bacteria, viruses or protozoa with equal or better efficacy of antibiotics, antiviral or antiparasitic agents. Anti-tick activities on Rhipicephalus (Boophilus) microplus, Hyalomma anatolicum, Hyalomma isaaci and Haemaphysalis bispinosa are discussed. Perspectives of these nanoparticles acting on bacteria, viruses and protozoa infections are also discussed.

United Nations Children's Fund (UNICEF)/United Nations Development Programme (UNDP)/World Bank/World Health Organization (WHO) implemented the Training in Tropical Diseases (TDR) program with excellent results; however, due to current challenges, this active program requires new and innovative solutions. Nowadays, Aedes aegyptis-borne diseases can be added among neglected diseases. Surveillance and control must be considered owing to a great risk of infection with dengue, chikungunya and zika viruses. Although investigations on several vaccines are in progress, new insights in term of development of drugs that evade from resistance are of paramount importance. Nanobiotechnology appears as one of the most innovative strategy in the search of new uses for old pharmaceuticals or in the development of innovative and intelligent nanomedicines for neglected diseases. Liposomes, solid lipid nanoparticles, nanoemulsions, polymeric nanoparticles, metallic nanoparticles, quantum dots, carbon dots and carbon nanotubes were the focus of the current advances. In this direction, we have focused this overview on new advances in diagnostic assays as nanobiosensors, antivirus and nanoinsecticides on Aedes aegyptis control.

A compatibilizer agent was successfully produced by grafting maleic anhydride (MA) to poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) chains on a reactive processing by mechanical mixing, using a mixture of PHBV, MA and dicumyl peroxide (DCP) as initiator. The resulting PHBV grafted MA (PHBV-g-MA) was characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC), and its properties were compared to neat PHBV. FTIR showed an absorption band at 699 cm-1 for PHBV-g-MA, related to CH group of grafted anhydride ring. The initial thermal degradation temperature of the compatibilizer agent was reduced when compared to neat PHBV. DSC analysis showed that after grafting MA onto PHBV the crystallization temperature was about 20ºC higher than neat PHBV, and the degree of crystallinity was increased. GPC analysis showed that MA when grafted onto PHBV led to a reduction of molecular weight and polydispersity.

A biomassa procedente do processamento de laranjas (CPWO) foi utilizada na produção de nanocelulose e do etanol da segunda geração. Primeiramente, vinte micro-organismos foram isolados da CPWO e suas capacidades de fermentação foram testadas. Dois destes, identificados como Candida parapsilosis IFM 48375 e NRRL Y-12969 (ATCC 22019), foram selecionados para a posterior fermentação. A biomassa foi destilada a vapor para o isolamento do óleo essencial (1,5% g g-1 de CPWO seco) e convertida em uma mistura de açúcares fermentáveis (40% g g-1 de CPWO seco) usando hidrólise ácida ou enzimática. Os hidrolisados foram fermentados utilizando micro-organismos isolados e a Saccharomyces cerevisiae. A levedura Candida parapsilosis IFM 48375 foi a mais eficiente na fermentação dos açúcares obtidos desta biomassa e os maiores rendimentos de bioetanol (21% g g-1 de CPWO seco) foram alcançados. A nanocelulose (2,5% g g-1 de CPWO seco) e as nanofibras (0,5% g g-1 de CPWO seco) foram isoladas partindo de bioresíduos vindo da hidrólise enzimática e da fermentação alcoólica e este resultado é o primeiro do gênero.

Citrus processing waste from oranges (CPWO) was explored for the production of nanocellulose and bioethanol. After the isolation of 20 microorganisms from CPWO, their fermentation abilities were screened and two microorganisms identified as Candida parapsilosis strains IFM 48375 and NRRL Y-12969 (ATCC 22019) were selected for a further fermentation. The CPWO was steam distilled for the isolation of essential oil (1.5% g g-1 of dry CPWO) and converted into a mixture of fermentable sugars (40% g g-1 of dry CPWO) using acid or enzymes hydrolyses. Hydrolyzates were fermented with three different yeast strains, the two Candida sp. and Saccharomyces cerevisiae. Candida parapsilosis strain IFM 48375 accomplished excellent results in ethanol production (21% g g-1 of dry CPWO) from CPWO, higher when compared to other strains. Nanocellulose (2.5% g g-1 dry CPWO) and nanofibers (0.5% g g-1 dry CPWO) were isolated from solid residues obtained from enzymatically treated and fermented CPWO. To the best of our knowledge, this work reports for the first time the nanocellulose production from CPWO.

Hidróxidos duplos lamelares (HDLs) têm sido amplamente investigados devido às suas diversas aplicações nas indústrias de materiais e biotecnologia. A combinação de nanopartículas de prata com o material biocompatível HDL pode criar um novo material híbrido com novas propriedades sinergísticas. Neste trabalho, nanopartículas de prata biogênicas (AgNPbio) foram associadas com Mg-Al HDL para obter o material híbrido HDL-AgNPbio. O novo material híbrido obtido foi caracterizado por difratometria de raios X (XRD), microscopias eletrônica de transmissão (TEM) e de varredura com espectroscopia de energia dispersiva por raios-X (MEV-EDS), espectrometria de emissão atômica por plasma acoplado indutivamente (ICP-OES) e espectroscopia na região do infravermelho com transformada de Fourier (FTIR). O HDL foi eficiente em adsorver nanopartículas de prata devido à carga superficial oposta entre as AgNPbio (ζ = -13,2 mV) e o HDL (ζ = +3,2 mV). Além disso, as AgNPbio não foram lixiviadas do material híbrido, mesmo após cinco ciclos de lavagem, indicando uma forte interação. Uma importante propriedade deste material híbrido foi a sua atividade antimicrobiana contra Staphylococcus aureus e Escherichia coli e ausência de efeito citotóxico em células de fibroblastos (V79). Este material híbrido é um interessante e promissor nanobiocompósito para aplicações biomédicas e cosméticas.

Layered double hydroxides (LDHs) have been widely investigated due to their several applications in the material and biotechnology industries. The combination of silver nanoparticles with biocompatible LDH material can create a new hybrid material with new properties. In this work, biogenic silver nanoparticles (AgNPbio) were associated with Mg-Al LDH to obtain the hybrid material LDH-AgNPbio. The new hybrid material obtained was characterized by X-ray diffractometry (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), transmission electron microscopy (TEM), inductively coupled plasma optical emission spectrometry (ICP-OES) and Fourier transform infrared spectroscopy (FTIR). LDH was efficient to absorb silver nanoparticles due to an opposite surface charge between AgNPbio (ζ = -13.2 mV) and LDH (ζ = +3.2 mV). Furthermore, AgNPbio was not lixiviated from LDH-AgNPbio, even after five washes, indicating a strong interaction. An important property of this hybrid material was its antimicrobial activity against Staphylococcus aureus and Escherichia coli and absence of cytotoxic effect to fibroblast cell (V79). This hybrid material is an interesting and promising nanobiocomposite for biomedical and cosmetic applications.

A obtenção de informações sobre uma rota biossintética é um procedimento complexo e trabalhoso. Neste sentido, o presente trabalho apresenta uma nova abordagem para a análise inicial da biossíntese de produtos naturais fluorescentes usando a biossíntese da violaceína como exemplo. Para tanto, uma cultura da Chromobacterium violaceum foi inoculada em um biorreator de onde alíquotas eram retiradas a cada 2 h para posterior análise por espectroscopia de fluorescência 2D. As matrizes de emissão-excitação obtidas demonstraram o comportamento dinâmico dos sinais de fluoróforos que são consumidos e produzidos pela bactéria. Estes sinais foram resolvidos pelo método PARAFAC (análise paralela de fatores) perfazendo um total de seis espécies químicas. O triptofano e a violaceína foram identificados por comparação espectral. A identificação dos outros fluoróforos mostrou-se a etapa crítica devido à falta de banco de dados de produtos naturais fluorescentes para comparação. Por fim, esta metodologia apresenta um grande potencial para fornecer informações da biossíntese de produtos naturais.

Obtaining information about a biosynthetic pathway is a complex and laborious procedure. In this sense, this work presents a new approach for the initial analysis of the biosynthesis of fluorescent natural products using as example the violacein biosynthesis. For this, a culture of Chromobacterium violaceum was grown in a bioreactor from which aliquots were collected every 2 h for subsequent analysis by multi-wavelength fluorescence spectroscopy. The excitation-emission matrices demonstrated the dynamic behavior of the fluorophores signal that are consumed and produced by the bacterium. These signals were resolved by PARAFAC (parallel factor analysis) method totalizing six pure components. Tryptophan and violacein were identified by comparison to spectra available in the literature. The identification of other fluorophores was critical step due to the lack of a database of fluorescent natural products to compare spectra. Finally, this methodology has great potential to achieve a deeper insight into the biosynthesis of natural products.

O desenvolvimento de nanobiosensores é um dos avanços mais recentes no campo da nanotecnologia. A investigação sobre nanobiosensores ópticos com dimensões submicrométricas tem aberto novos horizontes para as medições intracelulares. Aproveitando as propriedades únicas dos nanomateriais, nanobiosensores mais rápidos e sensíveis podem ser desenvolvidos. Além de serem sensíveis e rápidos, os estudos de nanobiosensores têm voltado seus esforços para o desenvolvimento de sensores baseados em nanomateriais que são acessíveis, robustos e reprodutíveis. Os nanobiosensores estão equipados com sondas biorreceptoras imobilizadas, por exemplo, anticorpos, substrato de enzima. A excitação por laser é transmitida para o sistema fotométrico na forma de sinal óptico (fluorescência). Os nanobiosessores poderão revolucionar no futuro o diagnóstico de doenças. A presente revisão discute os conceitos básicos, a evolução e as aplicações biomédicas de nanobiosensores.

Development of nanobiosensor is one of the most recent advancement in the field of Nanotechnology. Research on optical nanobiosensors with submicron-sized dimensions has opened new horizons for intracellular measurements. Taking advantage of the unique properties of the nanomaterials, faster and sensitive nanobiosensors can be developed. Apart from being sensitive and fast, the studies related to nanobiosensors have geared their efforts towards the development of nanomaterial-based sensors that are affordable, robust and reproducible. The nanobiosensors are equipped with immobilized bioreceptor probes, e.g., antibodies, enzyme substrate. Laser excitation is transmitted to photometric system in the form of optical signal (fluorescence). Nanobiosensors will revolutionize the future of disease diagnosis. The present review discusses the basic concepts, developments and the biomedical applications of nanobiosensors.

The production of bioethanol from pretreated lignocellulosic materials requires the utilization of microorganisms adapted to ferment the materials in conditions were high consistency, temperatures and inhibitors concentrations were commonly found. The yeast immobilization in calcium alginate capsules has been reported to enhance the yeast protection and increase the efficiency in the fermentation process. In this work, it was investigated the use Saccharomyces cerevisiae immobilized in calcium alginate and its performance in simultaneous saccharification and fermentation (SSF) of diluted-acid-pretreated Pinus radiata. Results showed that when immobilized yeast was used, the bioethanol yield from pretreated wood was higher than with free yeast cells during a SSF process. Maximum ethanol yield obtained from the acid pretreated and milled wood chips was 153 L/ton wood, while from the hydrolysate fraction it was 18 L/ton wood. The sum of ethanol produced from dilute acid pretreated P. radiata for both solid and liquid fractions was 171 L ethanol/ton wood from a maximum theoretical of 236 L/ ton pretretated wood (or 72% of conversion).

Fatores estruturais que modulam a atividade das porfirinas englobam os ligantes equatoriais, o metal central e o número e estrutura dos seus ligantes axiais. A esses fatores se associam o microambiente fornecido por apoproteínas, solventes e membranas. Porfirinas são bastante utilizadas para a construção de estruturas supramoleculares com diferentes aplicações. A modulação da atividade das porfirinas tem sido freqüentemente obtida pela imitação da natureza, ou seja, fornecimento de diferentes microambientes. A associação das porfirinas a nanoestruturas lipídicas pode mudar a atividade destes compostos de tal forma a mimetizar diferentes enzimas como a SOD, citocromo P450, peroxidases e outros. As formas reativas das porfirinas são estados de alta valência: metal-oxo-πcátion e metal-oxo produzidos pela reação com peróxidos e perácidos. A modulação da atividade de porfirinas por nanoestruturas lipídicas também tem sido obtida para hemeproteínas uma vez que nanoestruturas lipídicas afetam a conformação das proteínas.

The structural factors modulating porphyrin activity encompass pyrrole and equatorial ligands, as well as the central metal and the number and structure of their axial ligands. Of equal importance is the microenvironment provided by apoproteins, solvents and membranes. Porphyrins are often used to construct supramolecular structures with different applications. The modulation of activity of the porphyrins has been frequently achieved by mimicking nature, i.e., by the provision of different microenvironments for these molecules. The association of porphyrins to surfactant- and lipid-containing nanostructures has changed the activity of these compounds to mimic different enzymes such as SOD, cytochrome P450, peroxidases and others. In determined conditions, the reactive forms of the porphyrins are high-valence states of oxo-metal-πcations and oxo-metal produced by the reaction with peroxides and peracids. The modulation of porphyrin activity by surfactant- and lipid-containing nanostructures has also been achieved for hemeproteins, as the lipid nanostructures affect the conformation of proteins.