Influence of diimine bidentate ligand in the nitrosyl and nitro terpyridine ruthenium complex on the HSA/DNA interaction and antiviral activity.

Nitric oxide (NO) acts in different physiological processes, such as blood pressure control, antiparasitic activities, neurotransmission, and antitumor action. Among the exogenous NO donors, ruthenium nitrosyl/nitro complexes are potential candidates for prodrugs, due to their physicochemical properties, such as thermal and physiological pH stability. In this work, we proposed the synthesis and physical characterization of the new nitro terpyridine ruthenium (II) complexes of the type [RuII(L)(NO2)(tpy)]PF6 where tpy = 2,2':6',2″-terpyridine; L = 3,4-diaminobenzoic acid (bdq) or o-phenylenediamine (bd) and evaluation of influence of diimine bidentate ligand NH.NHq-R (R = H or COOH) in the HSA/DNA interaction as well as antiviral activity. The interactions between HSA and new nitro complexes [RuII(L)(NO2)(tpy)]+ were evaluated. The Ka values for the HSA-[RuII(bdq)(NO2)(tpy)]+ is 10 times bigger than HSA-[RuII(bd)(NO2)(tpy)]+. The sites of interaction between HSA and the complexes via synchronous fluorescence suppression indicate that the [RuII(bdq)(NO2)(tpy)]+ is found close to the Trp-241 residue, while the [RuII(bd)(NO2)(tpy)]+ complex is close to Tyr residues. The interaction with fish sperm fs-DNA using direct spectrophotometric titration (Kb) and ethidium bromide replacement (KSV and Kapp) showed weak interaction in the system fs-DNA-[RuII(bdq)(NO)(tpy)]+. Furthermore, fs-DNA-[RuII(bd)(NO2)(tpy)]+ and fs-DNA-[RuII(bd)(NO)(tpy)]3+ system showed higher intercalation constant. Circular dichroism spectra for fs-DNA-[RuII(bd)(NO2)(tpy)]+ and fs-DNA-[RuII(bd)(NO)(tpy)]3+, suggest semi-intercalative accompanied by major groove binding interaction modes. The [RuII(bd)(NO2)(tpy)]+ and [RuII(bd)(NO)(tpy)]3+ inhibit replication of Zika and Chikungunya viruses based in the nitric oxide release under S-nitrosylation reaction with cysteine viral.

Enhancing Methylene Blue Dye Removal using pyrolyzed Mytella falcata Shells: Characterization, Kinetics, Isotherm, and Regeneration through Photolysis and Peroxidation.

The potential of pyrolyzed Mytella falcata shells as an adsorbent for removing methylene blue dye molecules from aqueous solutions was investigated. The study found that the adsorbent produced at 600 °C of pyrolysis temperature, with an adsorbent mass of 0.5 g, particle diameter of 0.297-0.149 mm, and pH 12.0, demonstrated the highest dye molecule removal efficiency of 82.41%. The material's porosity was observed through scanning electron microscopy, which is favorable for adsorption, while Fourier-transform infrared spectroscopy and X-Ray diffraction analysis analyses confirmed the presence of calcium carbonate in the crystalline phases. The pseudo-second order model was found to be the best fit for the data, suggesting that the adsorption mechanism involves two steps: external diffusion and diffusion via the solid pores. The Redlich-Peterson isotherm model better represented the equilibrium data, and the methylene blue adsorption was found to be spontaneous, favorable, and endothermic. The hydrogen peroxide with UV oxidation was found to be the most efficient method of regeneration, with a regeneration percentage of 63% achieved using 600 mmol.L-1 of oxidizing agents. The results suggest that pyrolyzed Mytella falcata shells could serve as an ecologically viable adsorbent alternative, reducing the amount of waste produced in the local environment and at the same time removing pollutants from the water. The material's adsorption capacity remained almost constant in the first adsorption-oxidation cycles, indicating its potential for repeated use.

Gelatin Carbon Dots Interaction with Nitrosyl Ruthenium Complex: Fluorescence Quenching and Chemiluminescence Mechanisms.

Carbon dots (CDs) exhibit luminescence, biocompatibility, and higher water solubility. This material has been developed for biological applications, specifically in bioimaging. In this work, the gelatin carbon dots (CDg) was obtained from commercial gelatin using a hydrothermal method in domestic microwave, and the suppression fluorescent mechanism were enhanced by the addition of the [RuII(bdq)(NO)(tpy)]3+ (Rubdq-NO+) complex ion. After purification through a dialysis bag, the resulting CDs (CDg) exhibit fluorescent emission at 400 nm and maintained fluorescence stability in an aqueous solution (pH = 7) for 30 days under 5 ◦C. Fluorescence quenching studies revealed an electrostatic interaction between the negative charge from CDg (δ = - 20 mV) and the positively charged nitrosyl (NO+) ligand of the ruthenium complex (Rubdq-NO+), resulting in quenching of the CDg fluorescence due to the inner filter effects (IFE). The chemiluminescence reaction of CDg and Rubdq-NO-CDg in presence of norepinephrine (NOR) were evaluated. NOR in PBS are liable to undergo spontaneous oxidation to quinone form (NOR-quinone). CDg are believed interact with NOR-quinone and an electron transfer occur obtained CDg+ accompanied to green emission fluorescence (520 nm). While for Rubdq-NO-CDg in presence of NOR, the green emission occurs accompanied by NO0 release using DAF-2 probe.

Simple and cheap preparation of fluorescence paper sensor based in carbon dot for visual detection of chloramphenicol.

Carbon dots (CDs) are nanometer-scale particles produced from carbon sources that exhibit fluorescence emission. The present work presents the synthesis and characterization of CDs, as well as the sensing studies for the determination of chloramphenicol (CAP). CAP is an antibiotic used in human medicine and agriculture, and its indiscriminate use and inappropriate disposal have caused damage to human health and the environment. The carbonaceous precursor used in the synthesis of CDs was 3,4-diaminobenzoic acid (3,4-DABA) through the hydrothermal method via domestic microwave irradiation. The first synthesis procedure was carried out in the presence of water/ethanol (a-CDs) and the second in the presence of 1 mol/L sodium hydroxide/ethanol (b-CDs). The CDs were initially characterized in terms of spectroscopic properties in the ultraviolet and visible region (UV-visible), Fourier-transform infrared (FTIR) spectra, Raman spectroscopy, and fluorescence emission spectroscopy. Sensing studies for the antibiotic C were performed by fluorescence suppression in the presence of a- and b-CDs, as well as the precursor 3,4-DABA. The a- and b-CDs presented similar values of linear range 0.00080-0.0050 mg/ml and limit of detection (LOD) = 0.00030 mg/ml (0.30 ppm) for CAP. Then, a- and b-CDs were embedded in Whatman and Mellita® filter paper, and CAP sensing was evaluated through UV light excitation.

Biogenic metallic nanoparticles (Ag, TiO2, Fe) as potential fungicides for agriculture: are they safe for the freshwater mussel Anodontites trapesialis?

Silver (Ag), titanium dioxide (TiO2), and iron (Fe) nanoparticles (NPs) synthesized using the fungus Trichoderma harzianum are effective against the agriculture pathogen Sclerotinia sclerotiorum. However, their effects should be evaluated in aquatic organisms, as agriculture practices can contaminate the aquatic environment. Thus, this work evaluated sublethal effects of acute exposure (24 h) to AgNP, TiO2NP and FeNP, synthesized with T. harzianum, on the Neotropical freshwater bivalve Anodontites trapesialis, considering the hypothesis that suspension-feeding bivalves are susceptible to NPs toxicity. Individuals of A. trapesialis were divided into four groups (n = 8/group): a control group, kept in water only; a group exposed to AgNP; a group exposed to TiO2NP; and a group exposed to FeNP. The bioaccumulation of Ag, Ti, and Fe was evaluated in the gills, hemolymph, mantle, digestive gland, and muscle (foot). Lipoperoxidation, activities of the glutathione S-transferase, catalase, and superoxide dismutase, and glycogen concentration were quantified in the gills, mantle, and digestive gland. Ions (Na+, K+, Cl-, Ca2+, and Mg+2) and glucose concentrations were quantified in the hemolymph. Na+/K+-ATPase, H+-ATPase, Ca2+-ATPase, and carbonic anhydrase activities were assessed in the gills and mantle. Acetylcholinesterase activity was determined in the foot and adductor muscle. The mussels exposed to AgNP accumulated Ag in the gills, hemolymph, and foot, and showed a decrease in hemolymph concentrations of Na+ and Cl-, which was associated with the action of Ag ion (Ag+). The exposures to TiO2NP and FeNP led to the accumulation of Ti and Fe in the hemolymph, respectively, but did not promote additional effects. Accordingly, A. trapesialis showed bioaccumulation potential and susceptibility to AgNP, but was not susceptible to TiO2NP and FeNP. Thus, the preferential agricultural use of TiO2NP and FeNP over AgNP is highlighted.

Polymeric Nanorepellent Systems Containing Geraniol and Icaridin Aimed at Repelling Aedes aegypti.

Repellents are among the leading products used against diseases transmitted by the Aedes aegypti mosquito. However, their indiscriminate use or high concentrations can cause severe adverse reactions, particularly in children and pregnant women. To protect them, nanotechnology is a promising tool to encapsulate active compounds against degradation, increase their effectiveness, and decrease their toxicity, as it can promote the modified release of the active compound. This study aimed to develop polymeric nanocapsules containing the repellent actives geraniol and icaridin using low concentrations of the active component, with the objective of promoting effective activity and greater safety against adverse reactions. The nanocapsules were developed by the interfacial deposition method, and the physicochemical properties of the nanocapsules were evaluated using dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), zeta potential, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), release kinetics assay, and mathematical modeling. Cell viability was assessed by the MTT assay and genotoxicity analysis using the comet assay. The developed nanocapsules containing geraniol and icaridin showed mean diameters of 260 nm and 314 nm, respectively, with a polydispersity index < 0.2. The nanocapsules showed encapsulation efficiency values of 73.7 ± 0.1% for icaridin and 98.7 ± 0.1% for geraniol. Morphological analysis showed spherical nanocapsules with low polydispersity. The kinetic parameters calculated using the Korsmeyer−Peppas model indicated an anomalous release profile. Cell viability and genotoxicity analyses showed that the nanocapsules did not alter cell viability or damage DNA. The results demonstrate a promising nanostructured system with good physicochemical characteristics and good stability, with repellent activity against Aedes aegypti.

Clinical, radiographic, and genetic observations in 2 families with cleidocranial dysplasia.

The clinical, radiographic, and molecular alterations in 7 individuals belonging to 2 families with clinical characteristics of cleidocranial dysplasia (CCD) were investigated. The patients underwent karyotype and genetic sequencing examinations. Cytogenetic analysis did not demonstrate any alterations. The next-generation sequencing technique employed for the molecular analysis revealed sequence variations in the RUNX2 gene: c.568C>T (p.Arg190Trp) in exon 4 in family A and c.1205del (p.Pro402Argfs*82) in exon 9 in family B. Incomplete closure of anterior fontanels, hypoplastic clavicles, and dental changes were observed in all 7 patients. Uncommon clinical findings, such as partial hearing loss and bilateral clavicular agenesis, were noted in some patients. According to the literature consulted, this is the first time that the total absence of the pubic bone in a study subject is being reported. The variable expression among individuals of the same family and between families A and B suggests the absence of a genotype-phenotype relationship. Early diagnosis allows the dentist to minimize the effects of changes associated with CCD by monitoring and providing appropriate treatment, and the identification of genetic sequence variations enables appropriate family genetic counseling.

Using Chitosan-Coated Polymeric Nanoparticles-Thermosensitive Hydrogels in association with Limonene as Skin Drug Delivery Strategy.

Topical delivery of local anesthetics (LAs) is commonly used to decrease painful sensations, block pain throughout procedures, and alleviate pain after surgery. Dermal and/or transdermal delivery of LAs has other advantages, such as sustained drug delivery and decreased systemic adverse effects. This study reports the development of poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles coated with chitosan for the sustained release and topicality of benzocaine (BZC) and topical delivery. BZC PLGA nanoparticles or nonencapsulated drugs were further incorporated into Poloxamer hydrogels (Pluronic™ F-127). The nanoparticles showed a mean diameter of 380 ± 4 nm, positive zeta potential after coating with chitosan (23.3 ± 1.7 mV), and high encapsulation efficiency (96.7 ± 0.02%). Cellular viability greater than 70% for both fibroblasts and keratinocytes was observed after treatment with nanoparticles, which is in accordance with the preconized guidelines for biomedical devices and delivery systems. Both the nanoparticles and hydrogels were able to modulate BZC delivery and increase drug permeation when compared to the nonencapsulated drug. Furthermore, the incorporation of limonene into hydrogels containing BZC-loaded nanoparticles increased the BZC permeation rates. Non-Newtonian and pseudoplastic behaviors were observed for all hydrogel nanoformulations with or without nanoparticles. These results demonstrate that the hydrogel-nanoparticle hybrids could be a promising delivery system for prolonged local anesthetic therapy.

Hyperacute transplantation of umbilical cord mesenchymal stromal cells in a model of severe intracerebral hemorrhage.

Aim: Intracerebral hemorrhage (ICH) has limited therapeutic options. We have shown that an intravenous injection of human umbilical cord-derived mesenchymal stromal cells (hUC-MSC) 24 h after an ICH in rats reduced the residual hematoma volume after a moderate hemorrhage but was inefficient in severe ICH. Here, we investigated whether a treatment in the hyperacute phase would be more effective in severe ICH. Materials & methods: Wistar rats were randomly selected to receive an intravenous injection of hUC-MSC or the vehicle 1 h after a severe ICH. Results: The hyperacute treatment with hUC-MSC did not affect the 22-day survival rate, the motor function or the residual hematoma volume. Conclusion: These results indicate the need for optimization of hUC-MSC-based therapies for severe ICH.

Cellulose Hydrogels Containing Geraniol and Icaridin Encapsulated in Zein Nanoparticles for Arbovirus Control.

The most important arboviruses are those that cause dengue, yellow fever, chikungunya, and Zika, for which the main vector is the Aedes aegypti mosquito. The use of repellents is an important way to combat mosquito-borne pathogens. In this work, a safe method of protection employing a repellent was developed based on a slow release system composed of zein nanoparticles containing the active agents icaridin and geraniol incorporated in a cellulose gel matrix. Analyses were performed to characterize the nanoparticles and the gel formulation. The nanoparticles containing the repellents presented a hydrodynamic diameter of 229 ± 9 nm, polydispersity index of 0.38 ± 0.10, and zeta potential of +29.4 ± 0.8 mV. The efficiencies of encapsulation in the zein nanoparticles exceeded 85% for icaridin and 98% for geraniol. Rheological characterization of the gels containing nanoparticles and repellents showed that the viscoelastic characteristic of hydroxypropylmethylcellulose gel was preserved. Release tests demonstrated that the use of nanoparticles in combination with the gel matrix led to improved performance of the formulations. Atomic force microscopy analyses enabled visualization of the gel network containing the nanoparticles. Cytotoxicity assays using 3T3 and HaCaT cell cultures showed low toxicity profiles for the active agents and the nanoparticles. The results demonstrated the potential of these repellent systems to provide prolonged protection while decreasing toxicity.

Rutin-Functionalized Multi-Walled Carbon Nanotubes: Molecular Docking, Physicochemistry and Cytotoxicity in Fibroblasts.

Multi-Walled Carbon Nanotubes (MWCNT) have been functionalized with rutin through three steps (i. reaction step; ii. purification step; iii. drying step) and their physicochemical properties investigated with respect to morphological structure, thermal analysis, Fourier Transform Infrared Spectroscopy (FTIR), and cytotoxicity. The molecular docking suggested the rutin-functionalized MWCNT occurred by hydrogen bonds, which was confirmed by FTIR assays, corroborating the results obtained by thermal analyses. A tubular shape, arranged in a three-dimensional structure, could be observed. Mild cytotoxicity observed in 3T3 fibroblasts suggested a dose-effect relationship after exposure. These findings suggest the formation of aggregates of filamentous structures on the cells favoring the cell penetration.

Influence of the capping of biogenic silver nanoparticles on their toxicity and mechanism of action towards Sclerotinia sclerotiorum.

BACKGROUND: Biogenic nanoparticles possess a capping of biomolecules derived from the organism employed in the synthesis, which contributes to their stability and biological activity. These nanoparticles have been highlighted for the control of phytopathogens, so there is a need to understand their composition, mechanisms of action, and toxicity. This study aimed to investigate the importance of the capping and compare the effects of capped and uncapped biogenic silver nanoparticles synthesized using the filtrate of Trichoderma harzianum against the phytopathogenic fungus Sclerotinia sclerotiorum. Capping removal, investigation of the composition of the capping and physico-chemical characterization of the capped and uncapped nanoparticles were performed. The effects of the nanoparticles on S. sclerotiorum were evaluated in vitro. Cytotoxicity and genotoxicity of the nanoparticles on different cell lines and its effects on nontarget microorganisms were also investigated. RESULTS: The capped and uncapped nanoparticles showed spherical morphology, with greater diameter of the uncapped ones. Functional groups of biomolecules, protein bands and the hydrolytic enzymes NAGase, ß-1,3-glucanase, chitinase and acid protease from T. harzianum were detected in the capping. The capped nanoparticles showed great inhibitory potential against S. sclerotiorum, while the uncapped nanoparticles were ineffective. There was no difference in cytotoxicity comparing capped and uncapped nanoparticles, however higher genotoxicity of the uncapped nanoparticles was observed towards the cell lines. Regarding the effects on nontarget microorganisms, in the minimal inhibitory concentration assay only the capped nanoparticles inhibited microorganisms of agricultural importance, while in the molecular analysis of the soil microbiota there were major changes in the soils exposed to the uncapped nanoparticles. CONCLUSIONS: The results suggest that the capping played an important role in controlling nanoparticle size and contributed to the biological activity of the nanoparticles against S. sclerotiorum. This study opens perspectives for investigations concerning the application of these nanoparticles for the control of phytopathogens.

Interaction of the nitrosyl ruthenium complex [RuII (NH.NHq-R)(tpy)NO]3+ with human serum albumin: a spectroscopic and computational investigation.

The interaction between two nitrosyl ruthenium complexes [Ru (NH.NHq-COOH)(tpy)NO](PF6 )3 (RuBDQ) and [Ru (NH.NHq-H)(tpy)NO](PF6 )3 (RuBD) and human serum albumin (HSA) was investigated using spectroscopic and computational methods. From fluorescence experiments, a dynamic quenching mechanism and binding constants at a single site demonstrated the higher stability of the RuBDQ-HSA system at 308 K compared with RuBD-HSA. Thermodynamic parameters indicated that binding of RuBDQ and RuBD to HSA was mainly driven by hydrophobic interaction and hydrogen bonding, respectively. Synchronous fluorescence and FT-IR results suggested that interactions between both nitrosyl ruthenium complexes and HSA affected protein conformation. Competition experiments revealed that RuBDQ and RuBD bound to Sudlow sites I and II, respectively. Molecular docking results showed that RuBDQ interacted with Ser-192 and Ala-291 residues via hydrogen bonding and polar contact, respectively, whereas RuBD associated with Asn-391 via a polar interaction. Noncovalent interaction results suggested that van der Waals interactions were the main binding forces for both systems, i.e. RuBDQ associated with Trp-214 via van der Waals interaction and with Ty-150 via dipole-dipole bonding, whereas RuBD associated with Tyr-452 via van der Waals forces. The Asp-391 residue interacted with the nitrosyl ligand via polar contact and the terpyridine ligand via van der Waals interaction.

Methylphenidate effects on mice odontogenesis and connections with human odontogenesis.

The purpose of this study is to evaluate the effects of Methylphenidate exposure on mice odontogenesis and connect them by bioinformatics with human odontogenesis. Thirty-two pregnant Swiss mice were divided into treated group and control group, which received, respectively, 5 mg/kg of Methylphenidate and saline solution from the 5th to the 17th day of pregnancy. The mouse embryos tooth germs were analyzed through optical microscopy, and the data collected were analyzed statistically by Fisher's exact test. The presence and similarity of Methylphenidate-associated genes (Pharmgkb database) in both organisms and their interaction with dental development genes (AmiGO2 database) were verified on STRING database. Rates of tooth germ malformations were higher in treated than in control group (Control: 18; Treated: 27; p = 0.035). Mouse embryo malformations were connected with 238 interactions between 69 dental development genes with 35 Methylphenidate genes. Fourteen interactions for four Methylphenidate genes with four dental development genes, with human experimental data, were connected with mouse phenotype data. By homology, the interactions and conservation of proteins/genes may indicate similar outcomes for both organisms. The exposure to Methylphenidate during pregnancy affected odontogenesis in mouse embryos and may affect human odontogenesis. The study of malformations in mice, with a bioinformatics approach, could contribute to understanding of the Methylphenidate effect on embryo development. These results may provide novel hypotheses for further testing and reinforce the FDA protocol: as Methylphenidate is included in category C, its use during pregnancy should be considered if the benefits outweigh the risks.

Otoliths-composed gelatin/sodium alginate scaffolds for bone regeneration.

Evidence that otoliths, mineral-rich limestone concrescences present in the inner ear of bone fishes, can accelerate bone formation in vivo has been previously reported. The goal of this work was the development, characterization, and evaluation of the cytocompatibility of otoliths-incorporated sodium alginate and gelatin scaffolds. Cynoscion acoupa-derived otoliths were characterized by X-ray fluorescence spectrometry (FRX), particle size, free lime, and weight loss by calcination. Furthermore, otoliths were incorporated into sodium alginate (ALG/OTL-s) or gelatin (GEL/OTL-s) scaffolds, previously developed by freeze-drying. Then, the scaffolds were characterized by thermogravimetric analysis (TGA/DTG), differential scanning calorimetry (DSC), infrared spectroscopy with Fourier transform (FTIR), swelling tests, and scanning electron microscopy (SEM). Cytotoxicity assays were run against J774.G8 macrophages and MC3T3-E1 osteoblasts. Data obtained from TGA/DTG, DSC, and FTIR analyses confirmed the interaction between otoliths and the polymeric scaffolds. SEM showed the homogeneous porous 3D structure rich in otolith micro-fragments in both scaffolds. Swelling of the GEL/OTL-s (63.54 ± 3.0%) was greater than of ALG/OTL-s (13.36 ± 9.9%) (p < 0.001). The viability of J774.G8 macrophages treated with both scaffolds was statistically similar to the group treated with DMEM only (p > 0.05) and significantly higher than that treated with Triton-X (p < 0.01) at 72 h. Both scaffolds showed approximately 100% growth of MC3T3-E1 osteoblasts by 24 h, similarly to control (p > 0.05). However, by 48 h, only ALG/OTL-s showed growth similar to control (p > 0.05), whereas GEL/OTL showed a significantly lower growth index (p < 0.05). In conclusion, the physicochemical profiles suggest proper interaction between the otoliths and the two developed polymeric 3D scaffolds. Moreover, both materials showed cytocompatibility with J774.G8 macrophages but the growth of MC3T3-E1 osteoblasts was higher when exposed to ALG/OTL-s. These data suggest that sodium alginate/otoliths scaffolds are potential biomaterials to be used in bone regeneration applications. Graphical abstract.

How can nanotechnology help to combat COVID-19? Opportunities and urgent need.

Incidents of viral outbreaks have increased at an alarming rate over the past decades. The most recent human coronavirus known as COVID-19 (SARS-CoV-2) has already spread around the world and shown R0 values from 2.2 to 2.68. However, the ratio between mortality and number of infections seems to be lower in this case in comparison to other human coronaviruses (such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV)). These outbreaks have tested the limits of healthcare systems and have posed serious questions about management using conventional therapies and diagnostic tools. In this regard, the use of nanotechnology offers new opportunities for the development of novel strategies in terms of prevention, diagnosis and treatment of COVID-19 and other viral infections. In this review, we discuss the use of nanotechnology for COVID-19 virus management by the development of nano-based materials, such as disinfectants, personal protective equipment, diagnostic systems and nanocarrier systems, for treatments and vaccine development, as well as the challenges and drawbacks that need addressing.

Zein Nanoparticles Impregnated with Eugenol and Garlic Essential Oils for Treating Fish Pathogens.

The supply of food derived from aquaculture has increased significantly in recent years. The aim of this industrial sector is to produce sustainable products to meet the needs of consumers, providing food security and nutritional benefits. The development of aquaculture has faced challenges including disease outbreaks that can cause substantial economic losses. These diseases can be controlled using chemicals such as antibiotics. However, the indiscriminate use of these substances can have major negative impacts on human health and the environment with the additional risk of the emergence of resistant organisms. The present manuscript describes the use of phytotherapy in association with nanotechnology in order to obtain a more effective and less harmful system for the control of bacterial diseases in fish. Zein nanoparticles associated with eugenol and garlic essential oil were prepared through antisolvent precipitation and characterized. Zein nanoparticles are promising carrier systems as zein proteins are biodegradable and biocompatible and, in this way, good candidates for encapsulation of active ingredients. The system presented good physicochemical properties with an average particle diameter of approximately 150 nm, a polydispersity index lower than 0.2, and a zeta potential of approximately 30 mV. High encapsulation efficiency was obtained for the active compounds with values higher than 90%, and the compounds were protected against degradation during storage (90 days). The nanoparticle formulations containing the botanical compounds also showed less toxicity in the tests performed with a biomarker (Artemia salina). In addition, the systems showed bactericidal activity against the important fish pathogenic bacteria Aeromonas hydrophila, Edwardsiella tarda, and Streptococcus iniae in vitro. The present study opens new perspectives for the use of botanical compounds in combination with nanotechnology to treat fish diseases caused by bacteria, contributing to a more sustainable fish chain production.

Encapsulation of Trichoderma harzianum Preserves Enzymatic Activity and Enhances the Potential for Biological Control.

Trichoderma harzianum is a biological control agent used against phytopathogens and biostimulation in agriculture. However, its efficacy can be affected by biotic and abiotic factors, and microencapsulation has been used to maximize the efficacy. The objective was to develop polymeric microparticles to encapsulate T. harzianum, to perform physicochemical characterization to evaluate its stability, to evaluate effects on the soil microbiota, antifungal activity in vitro and enzymatic activity. Size distribution of wet and dry microparticles was 2000 and 800 µm, respectively. Scanning electron microscopy showed spherical morphology and encapsulation of T. harzianum. Photostability assays showed that encapsulation protected the fungus against ultraviolet radiation. The evaluation of the microbiota showed that the proportion of denitrifying bacteria increased when compared to the control. The T. harzianum encapsulation showed an improvement in the chitinolytic and cellulosic activity. In vitro tests showed that encapsulated fungus were able to provide a greater control of S. sclerotiorum.