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Ethnopharmacological relevance: Tucumã (Astrocaryum vulgare)is a fruit native to the Amazon region. Extracts from the peel and pulp are thought of as promising treatments for bacterial infections. The primary constituents of Tucumã oil and butter possess unsaturated carbon chains that are susceptible to oxidation by light or heat. The oils have high volatility and low aqueous solubility that limits their use without a vehicle. Nanotechnology refers to techniques to solve these problems. Nanostructured lipid carriers (NLC), for example, protect fixed oils degradation by heat or light, as well as from oxidation and evaporation, ensuring greater stability and function, thereby prolonging the useful life of the final product. Study objectives: The objective of this study was to evaluate the hemolytic, cytotoxic, antimicrobial and antibiofilm properties of an NLC containing Tucumã butter and oil soasto improve the solubility and photosensitivity of the compounds, generating better pharmacological efficacy. Materials and methods: The NLC was assessed for stability for 60 days. The cytotoxicity of nanoparticles in peripheral blood mononucleated cells was determined in culture using assays for cell viability, DNA damage, oxidative metabolism and damage to human erythrocytes. Antimicrobial activity was determined using the broth microdilution technique and antibiofilm activity according to standardized protocols. Results: The Tucumã NLC remained stable throughout the evaluated period, with pH between 5.22–5.35, monodisperse distribution (PDI

Brazilian fish farming goes together with the emergence of numerous bacterial diseases, with Aeromonas hydrophila being the main bacterial pathogen. As a consequence, antimicrobials are excessively used. Considering that antimicrobials are relatively stable and nonbiodegradable, medicinal plants and their phytochemicals have been used as alternative treatments of bacteriosis in fish farming. Limonene is a monoterpene available in two enantiomers: R-(+)-limonene and S-(-)-limonene. This study analyzed the antibacterial activity of the phytochemicals S-(-)-limonene and R-(+)-limonene against some bacteria isolated from silver catfish (Rhamdia quelen). Furthermore, by means of spectrophotometry and atomic force microscopy, we also investigated the combination therapy of phytochemicals with antimicrobials and their activity in terms of inhibiting biofilm formation. Six clinical isolates and a standard strain were selected for antimicrobial activity testing. Biofilm formation was tested in 96-well plates and nylon cubes. The most sensitive of the strains tested was the A. hydrophila strain (MF 372510). S-(-)-limonene and R-(+)-limonene had high minimum inhibitory concentrations, however, they strongly inhibited A. hydrophila biofilm formation. R-(+)-limonene and S-(-)-limonene had an additive effect when combined with florfenicol and an antagonistic effect with oxytetracycline. In general, the phytochemicals tested showed strong antibiofilm activity against A. hydrophila, and when in combination therapy with florfenicol, they showed an additive effect against the treatment of A. hydrophila.

The cubiu (Solanum sessiliflorum) is a tropical fruit native to the Amazon region and widely used in medicine and cosmetics, despite the lack of research regarding the actual safety and effectiveness of its use for these purposes. This study aimed to evaluated the phytochemical characterization, pharmacological properties (skin wound healing, antimicrobial and anti-inflammatory properties), and toxicity of cubiu extract. The cubiu antimicrobial capacity was determined against strains of Aeromonas caviae, Pseudomonas aeruginosa, and Sphingomonas paucimobilis. Additionally, cubiu toxicity (hemolysis, coagulation, cell viability, and genotoxicity tests), antioxidant activity (reactive oxygen species total levels), scratch assay (in vitro skin wound healing), and anti-inflammatory activity against phytohemagglutinin and in the scratch assay (Interleukin 1, interleukin 6, interleukin 10, tumor necrosis factor-alpha, and interferon-gamma levels), were evaluated. Human fibroblast cells were used to evaluate skin wound healing, and human peripheral blood mononuclear cells were used for the other assessments. Our findings showed that the cubiu extract is rich in phenolic compounds, the major compound being 5-caffeoylquinic acid. In addition, was effective against the three bacterial strains tested and inhibited and destroyed the biofilm formed by Pseudomonas aeruginosa. The cubiu extract also was no toxicity, maintained the hemocompatibility parameters in the biological range, improved cell viability, decreased reactive oxygen species total levels and pro-inflammatory cytokine levels, increased anti-inflammatory cytokine levels, and accelerated the wound healing process. In conclusion, this is the first research to prove that cubiu is an important compound for use in the skin diseases, promoting skin wound healing, antimicrobial and anti-inflammatory activities.

The pathophysiological mechanisms associated with immune responses to the opportunistic bacterial pathogen Providencia rettgeri in fish species are unknown. The aim of this study was to evaluate whether purinergic signaling generates anti-inflammatory or pro-inflammatory profiles in lymphoid immune organs of the Nile tilapia (Oreochromis niloticus) experimentally infected by P. rettgeri. Adenosine triphosphate (ATP) and adenosine diphosphate (ADP) hydrolysis activities in the spleen and triphosphate diphosphohydrolase (NTPDase) in the head kidney decreased in experimentally P. rettgeri-infected Nile tilapia on days seven and fourteen post-infection (PI) compared to the control group. At these same time points, splenic and head kidney adenosine deaminase (ADA) activity, and levels of ATP, interleukin-15 (IL-15) and metabolites of nitric oxide (NOx) increased in infected animals compared to their respective control groups; this was also observed for serum ATP levels. No significant difference was observed between groups regarding 5′-nucleotidase activity. These results suggest that purinergic signaling in lymphoid immune organs of Nile tilapia exerts a pro-inflammatory profile in response to P. rettgeri infection. This response contributes to the inhibition of immune and inflammatory responses by reduction of ATP hydrolysis and augmentation of ATP in the extracellular environment as well as augmentation in adenosine deamination and its possible reduction in the extracellular environment, leading to a self-sustained pro-inflammatory cycle, corroborated by excessive content of ATP (extracellular milieu), IL-15 and NOx levels. Purinergic signaling may thereby contribute to the pathophysiology of P. rettgeri infection.

Bacterial diseases are one of the major problems in freshwater fish culture and have been linked to significant losses and high mortality rate. In this study, Nile tilapia Oreochromis niloticus was infected by Providencia rettgeri to evaluate the oxidative stress and antioxidant responses in the fish tissues. Juvenile Nile tilapia was divided into two groups, as follow: control (uninfected) and experimentally infected with 100 μL of P. rettgeri suspension containing 2.4 × 107 viable cells/fish, and the liver and kidney tissues were collected on days 7 and 14 post-infection (PI). Liver and kidney ROS and lipid peroxidation levels were high in infected fish on day 14 PI compared to control group, while superoxide dismutase activity was lower in liver (days 7 and 14 PI) and kidney (day 14 PI) compared to their respective control groups. Liver and kidney antioxidant capacity against peroxyl radicals, non-proteic, and proteic thiols levels was lower in infected tilapia on day 14 PI compared to control group. Based on these results, P. rettgeri infection may elicit oxidative damage via increased ROS production, decreased ROS elimination and inhibits enzymatic and non-enzymatic antioxidant defense systems; which may contribute directly to disease pathophysiology of infected animals.

Grape pomace is a by-product of the winemaking process, rich in bioactive compounds such as resveratrol and has antioxidant and antimicrobial properties. Recent evidence has demonstrated the protective effects of grape against impairment of the phosphoryl transfer network, a system linked to energetic homeostasis of high-energy phosphoryl transfer, to maintain energetic balance. Also, Pseudomonas aeruginosa infection in fish has been related to severe impairment of the branchial phosphoryl transfer network via inhibition of creatine kinase (CK), adenylate kinase (AK) and pyruvate kinase (PK) activities. Thus, the aim of this study was to evaluate whether dietary supplementation with grape pomace flour (GPF) is able to reduce or prevent the impairment of cellular energetic homeostasis in grass carp (Ctenopharyngodon idella) experimentally infected by P. aeruginosa. Branchial CK (cytosolic and mitochondrial), AK, and PK activities were lower in infected animals on day 15 post-infection (PI) compared to uninfected fish, while lactate dehydrogenase (LDH) activity was higher. Branchial reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), lipid oxidation (LOOH) and protein carbonylation levels were higher, while the level of non-proteic (NPSH) and proteic (PSH) thiols was lower in infected fish on day 15 PI, as compared to uninfected fish. The use of 300 mg of GPF/kg of feed was able to ameliorate the activities of CK, AK, PK, and LDH as compared to infected fish, but their activities remained different from the control group. On the other hand, dietary supplementation with 300 mg of GPF/kg of feed was able to prevent all alterations linked to oxidative damage elicited by disease. Based on this evidence, inhibition of the phosphoryl transfer network may contribute to the impairment of intracellular energetic communication between cellular ATP synthesis and consumption and is mediated by oxidative damage in the gills of fish infected by P. aeruginosa. The use of 300 mg of GPF/kg of feed exerted protective effects on branchial energetic metabolism linked to ATP metabolism by reducing the impairment in cellular energetic homeostasis; its effects can be mediated by the prevention of SH group oxidation.

Pseudomonas aeruginosa is a Gram-negative opportunistic bacterial pathogen in aquaculture systems being associated to extensive liver damage caused by oxidative stress in both marine and freshwater fish. Dietary supplementation with natural antioxidants is considered a rational strategy to prevent hepatic diseases involved with oxidative stress. Bio-residues resulting from the wine industry, such as grape pomace, are potential sources of bioactive phenolic compounds that can be applied as supplement for animal production. Thus, the aim of this study was to evaluate whether dietary supplementation with grape pomace flour (GPF) was able to prevent or reduce the hepatic oxidative damage of grass carp, Ctenopharyngodon idella, experimentally infected by P. aeruginosa. Hepatic reactive oxygen species (ROS), metabolites of nitric oxide (NOx), thiobarbituric acid reactive substances, and protein carbonylation levels were higher in fish experimentally infected by P. aeruginosa compared to the control group. Hepatic superoxide dismutase and catalase activities and antioxidant capacity against peroxyl radical levels were also higher in fish experimentally infected by P. aeruginosa compared to the control group. Dietary supplementation with 300 mg/kg GPF prevented all alterations elicited by P. aeruginosa, with the exception of protein carbonylation levels. The dietary supplementation with 150 mg/kg GPF was not able to avoid alteration of the analyzed variables, being results similar to those infected (positive control). Based on these results, dietary supplementation with 300 mg/kg GPF prevented P. aeruginosa-induced liver damage in grass carp, and this protective effect occurred through prevention on excessive ROS and NOx production, as well as via prevention of lipid damage. Moreover, 300 mg/kg GPF exerted its hepatoprotective effects by improving enzymatic and non-enzymatic antioxidant defense system. In summary, this supplementation can be an interesting approach to prevent P. aeruginosa-induced liver damage.

It is becoming evident that bacterial infectious diseases negatively affect gill energy metabolism, mainly because it causes alterations of enzymes that belong to the phosphotransfer network, such as creatine kinase (CK), adenylate kinase (AK) and pyruvate kinase (PK). Thus, the aim of this study was to evaluate whether the phosphotransfer network could be one pathway involved in the bioenergetic imbalance during Providencia rettgeri infection, as well as to investigate the bacteria's influence on adenosine triphosphate (ATP)-dependent enzymes. In this study, branchial cytosolic and mitochondrial CK activity decreased in infected animals on day 14 post-infection (PI) when compared to its respective control group. Moreover, branchial sodium-potassium pump (Na+/K+-ATPase) and proton-pump (H+-ATPase) activities decreased in infected animals on day 14 PI compared to the control. Finally, branchial thiobarbituric acid reactive substance levels increased in infected animals on day 14 PI, while non-protein thiol (NPSH) levels decreased. No significant difference was observed between groups regarding AK and PK activities. In summary, the impairment of CK activity elicited by P. rettgeri caused an impairment in branchial energetic homeostasis, reducing ATP availability in the gills. Moreover, inhibition of CK activity provokes an impairment of ATP-dependent enzymes, such as Na+/K+-ATPase and H+-ATPase, which can be mediated by lipid oxidative damage and reduction of NPSH content.

The spleen is a secondary lymphatic organ that has an important role in fish immune and inflammatory responses. Reports have suggested a role of purinergic signaling in immune and inflammatory responses during bacterial infection; however, the role of this pathway during Pseudomonas aeruginosa infection remains unknown. The aim of this study was to investigate the involvement of purinergic signaling in the pathogenesis of P. aeruginosa infection of grass carp, Ctenopharyngodon idella. In addition, grape pomace flour (GPF), a bio-residue of the wine industry, was assessed as a dietary supplement and whether it was able to modulate purinergic signaling and improve the immune and inflammatory responses of C. idella, experimentally infected with P. aeruginosa. Nucleoside Triphosphate diphosphohydrolase (NTPDase) activity was downregulated in the serum and spleen of fish experimentally infected with P. aeruginosa, compared to the control group. By contrast, serum and splenic adenosine deaminase (ADA) activity was stimulated in fish experimentally infected with P. aeruginosa compared to the control group. Dietary supplementation with GPF was able to prevent all alterations induced by infection. Serum and splenic metabolites of nitric oxide (NOx) were higher in fish experimentally infected with P. aeruginosa compared to the control group, and GPF supplementation was able to prevent this alteration. Serum and splenic myeloperoxidase and catalase activities were also higher in fish experimentally infected with P. aeruginosa compared to the control group, and again, the use of GPF was able to prevent these alterations. Based on these metabolic changes, purinergic signaling contributed to the pro-inflammatory profile of immune lymphatic organs during P. aeruginosa infection and to disease pathophysiology. Dietary supplementation with GPF modulated the inflammatory response by altering serum and splenic purinergic signaling. GPF may be means of improving immune and inflammatory responses resulting from P. aeruginosa infection of grass carp.

The synthesis of 3-alkyl-5-trifluoromethyl-1H-pyrazole-1-carboxamides, 3-alkyl5-trifluoromethyl-1H-pyrazole-1-thiocarboxamides, and 2-(3-alkyl-5-trifluoromethyl-1H-pyrazol1-yl)-thiazoles derivatives are reported. [3 + 2] cyclocondensations for a series of long alkyl chain 1,1,1-trifluoro-4-methoxyalk-3-en-2-ones and semicarbazide or thiosemicarbazide were carried out in ethanol, an eco-friendly medium. The series of trifluoromethyl-1H-pyrazol-1-ylthiocarboxamide following a [3 + 2] cyclocondensation with 2-bromoacetophenone were converted into two series of 2-(3-alkyl-5-trifluoromethyl-1H-pyrazol-1-yl)-thiazoles. Good yields (69-96%) of the isolated products were obtained. The structures of the new long alkyl chain 1H-pyrazoles and 2-(1H-pyrazol-1-yl)thiazoles were characterized using 1 H, 13C, and 19F nuclear magnetic resonance (NMR) spectroscopy and electrospray ionization tandem mass spectrometric (ESI MS/MS) data. Moreover, some of the products were evaluated for their antimicrobial activity against Gram-negative Escherichia coli American Type Culture Collection (ATCC) 35218, Salmonella enteritidis ATCC 13076, and Pseudomonas aeruginosa ATCC 15692; and Gram-positive Staphylococcus aureus ATCC 6538, methicillin resistant Staphylococcus aureus (MRSA clinical isolate), Streptococcus sp. (clinical isolate), and Candida albicans ATCC 14053 and Candida krusei ATCC 6258 fungi. All the tested 1H-pyrazoles exhibited antibacterial and antifungal activities at the tested concentrations. The compounds from series 4 were found to be powerful against MRSA.

Glycerol monolaurate (GML) is composed of lauric acid and glycerol. Research has shown that such organic acids can minimize negative effects caused by mycotoxins. Therefore, the objective of this study was to determine whether adding GML (free or encapsulated) to chick feed minimizes the effects of natural contamination by fumonisin (Fusarium verticillioides), evaluating parameters such as biochemistry, antioxidant properties, histological analysis and chick growth. Were weighed 84 chicks of the Cobb 500 strain and randomly distributed them into six groups of two replicates each (n = 14). The F group consumed feed containing fumonisin (levels 400 ppb), with no performance enhancer; F + ZB- feed with fumonisin (levels 400 ppb) + zinc bacitracin; F + GLM100 - feed with fumonisin (levels 400 ppb) + 100 mg of GML/kg of feed; F + NGLM4 - feed with fumonisin (levels 400 ppb) + 4 mg GML/kg in nanocapsules added to the feed; F + NGLM8 - fumonisin feed (levels 400 ppb) + 8 mg GML/kg in nanocapsules in the feed; and F0 - fumonisin-free feed (negative control) + zinc bacitracin. The body weights of birds fed with feed fumonisin-contaminated feed (F, F + ZB, F + GLM100, F + NGLM4 and F + NGLM8) were significantly lower (P 0.05) than those of the negative control (F0), despite the use of GML (free and nanoencapsulated). Serum levels of triglycerides, globulins and cholesterol were significantly lower in the F0 group than in the other groups (P 0.05), except for the F + NGLM8 group. Significantly greater levels of lipid peroxidation were observed in livers in the groups that consumed fumonisin than in the control group (F0) (P 0.05). Serum levels of reactive oxygen species were significantly lower in groups F + NGLM8 and F0 than in the other treatments (P 0.05). Superoxide dismutase activity was significantly greater in groups F + NGLM8 and F0 than in groups F, F + ZB and F + NGLM4. Hepatic catalase activity was significantly lower in birds that consumed contaminated feed (F, F + ZB, F + GLM100, F + NGLM4 and F + NGLM8) than in the control group (F0). Greater hepatic glutathione S-transferase activity was observed in the F + NGLM8 group than in the F0 group. Despite changes in cellular lesions in the liver, no histological changes were observed in the liver or intestines, even though visually there was yellowing of the liver. Taken together, the data suggest that free or nano-encapsulated GML did not minimize oxidative stress caused by fumonisin, and consequently, these birds had less weight gain.

This study investigated the chemical constituents of Gaultheria procumbens essential oil and is the first to relate cytogenotoxicity with oxidative metabolism and antimicrobial activity. Chromatographic analysis of the essential oil showed methyl salicylate (99.96%) and linalool (0.04%) as the major compounds. The essential oil showed no signs of cytogenotoxicity at different concentrations (1.82 to 58.34 mg mL−1). Furthermore, G. procumbens essential oil and methyl salicylate were used to evaluate the minimal inhibitory concentrations (MIC) and minimal microbicidal concentrations (MMC). The results showed efficacy against several microorganisms, including Aeromonas caviae, Candida albicans, and Mycobacterium fortuitum with MIC values ranging from 1.82 to 3.64 mg mL−1 and MMC values ranging from 3.64 to 12.67 mg mL−1, which were confirmed by time-kill kinetics. Based on our results, the essential oil is a promising alternative to developing future formulations to treat infections caused by microorganisms.

Inflammatory dermatoses are prevalent worldwide, with impacts on the quality of life of patients and their families. The aim of this study was to determine the anti-inflammatory effects of Achyrocline satureioides oily extracts and nanocapsules on the skin using a mouse model of irritant contact dermatitis induced by croton oil, and a skin inflammation model induced by ultraviolet B (UVB) radiation. The mice were treated with 15 mg/ear oily extract (HG-OLAS) or nanocapsules (HG-NCAS) of A. satureioides incorporated into Carbopol® 940 hydrogels. We found that HG-OLAS and HG-NCAS formulations reduced ear edema in croton oil-induced lesions with maximum inhibitions of 54±7% and 74±3%, respectively. HG-OLAS and HG-NCAS formulations decreased ear edema induced by UVB radiation (0.5 J/cm2), with maximum inhibitions of 68±6% and 76±2% compared to the UVB radiation group, respectively. HG-OLAS and HG-NCAS modulated myeloperoxidase (MPO) activity after croton oil induction. Furthermore, croton oil and UVB radiation for 6 and 24 h, respectively, stimulated polymorphonuclear cells infiltration. The topical treatments reduced inflammatory processes, as shown by histological analysis. Together, the data suggest that topical application of A. satureioides oily extracts and nanocapsules produced antiedematogenic and anti-inflammatory effects. They constitute a compelling alternative for treatment of skin injuries.

The grape culture is quite affected by fungi. Among them is Glomerella cingulata, whose control is carried by synthetic fungicides such as mancozeb, which can cause damage to human and environmental health. An alternative is the use of natural fungicides, such as eugenol. It has already proven antifungal activity but has instability problems. In this context, nanoencapsulation would be a possibility to minimize the mancozeb toxicity and the eugenol instability. In this study, nanoemulsions containing eugenol and mancozeb, isolated and in association, were prepared by the spontaneous emulsification method. Afterwards, the antifungal activity, through the macrodilution technique in broth and the physicochemical stability of these formulations were evaluated. The nanoemulsions presented adequate nanometric characteristics with diameter between 180 and 210 nm, polydispersity index less than 0.3, negative zeta potential and acid pH. Besides good physicochemical stability. The compounds when nanoencapsulated presented an antifungal activity against G. cingulata with efficacy 103 and 3 times better for mancozeb and eugenol, respectively, compared to its free form. The study demonstrates the viability of obtaining nanoemulsions containing mancozeb and/or eugenol with antifungal activity against of G. cingulata, having these an innovative character for the treatment of vine-growing pests.

La infestación por garrapatas (Rhipicephalus microplus), genera importantes pérdidas en la producción bovina. El objetivo de este estudio fue investigar si el aceite esencial de Eucalyptus globulus en diferentes nanosistemas (nanoemulsiones y nanocápsulas) es capaz de potenciar el efecto negativo sobre la reproducción de la garrapata, interfiriendo en su oviposición y eclosión de los huevos. Las hembras engordadas de R. microplus se obtuvieron de vacas naturalmente infestadas. En condiciones experimentales, estas hembras fueron sumergidas en soluciones de ensayo a concentraciones de 1, 5 y 10%, conteniendo aceite esencial puro de eucalipto; Y soluciones de la misma en nanocápsulas y nanoemulsiones, a concentraciones de 0,5, 1 y 5%. Las pruebas con aceite esencial de eucalipto puro, a concentraciones de 5 y 10%, mostraron 85 y 97,8% de eficacia, respectivamente. Sin embargo, el aceite encapsulado no fue capaz de potenciar el efecto carrapaticida, presentando 61,2% y 50% de eficacia (al 5%), utilizando nanoemulsiones y nanocápsulas. Por lo tanto, nuestros resultados nos permitieron concluir que el aceite esencial de E. globulus, en su forma pura, interfería negativamente en la reproducción de R. microplus; Sin embargo, las formas nanoestructuradas tenían baja eficacia.

The aim of this study was to evaluate the efficacy and safety of several anesthetics in the brachyuran crab Neohelice granulata, an emergent experimental model. The essential oils (EOs) of Lippia alba, Aloysia tryphilla, and Melaleuca alternifolia (tea tree oil; TTO), the isolated compounds eugenol, menthol, terpinen-4-ol, and the nanoencapsulated form of TTO, were administered in one or more of the following ways: added to the water (immersion), through an arthrodial membrane (injected), or by oral gavage. Unexpectedly, most EOs did not produce an anesthetic effect after immersion. Only TTO and eugenol induced anesthesia by immersion, with very long induction and recovery times compared to anesthesia of other crustaceans. However, a good anesthetic effect was observed with the injection of terpinen-4-ol and nanoencapsulated TTO in N. granulata; both demonstrated ideal induction and recovery times. These substances appear to be promising anesthetic alternatives for crustaceans.

Several species of the genus Ceiba (Malvaceae) are ethnopharmacologically used. Thus, this study aimed to investigate the in vitro beneficial properties of the aqueous stem bark extract of Ceiba speciosa. The extract presented a great amount of phenolic compounds (117.4 ± 6.2 mg GAE/g). The antioxidant activity was assessed by DPPH (IC50 = 42.87 μg/mL), ORAC (2351.17 μmol TE/g) and FRAP (235.94 μM FeSO4/g) methods. In addition, the extract reduced MCF-7 cell viability as assessed by MTT. However, it prevented mitochondrial membrane depolarization and reduced caspase-9 activity induced by hydrogen peroxide. In conclusion, these findings indicate the extract is an excellent source of natural antioxidants and is able to protect ROS-induced cell death. Therefore, C. speciosa extract may possess beneficial properties for application in pharmaceutical industry as an antioxidant. However, further studies to better elucidate its mechanisms and to isolate its active compounds are required.

The increase of microbial resistance generates the search for new substances with antimicrobial potential. The essential oil of Cymbopogon flexuosus (Lemongrass) stands out in the literature for its antimicrobial, insecticide and antioxidant properties, but it has high volatilization and low stability, and the nanoencapsulation of this oil could be an alternative to overcome these limitations. Thus, the objective of this study was to develop, for the first time, nanoemulsions containing the essential oil of C. flexuosus, through a method that does not use organic solvent and with temperature control to avoid the volatilization of the oil, characterize and evaluate of stability and the antimicrobial and antibiofilm activities of these nanoemulsions. Nanoemulsions presented adequate physicochemical characteristics (average size less than 200 nm, polydispersity index less than 0.3, negative zeta potential and acid pH) which were maintained during 90 days of storage, and the nanoencapsulation of the C. flexuosus oil enhanced its therapeutic efficacy against the microorganisms evaluated in this study compared to the free oil. These results are very promising because among the microorganisms that the nanoemulsion containing C. flexuosus was able to inhibit the formation of biofilm are the bacteria Pseudomonas aeruginosa and Staphylococcus aureus, which were recently listed by the World Health Organization as priority pathogens for development of new antibiotics.

It is recognized that the purinergic system, through the activities of ectonucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-5′-nucleotidase (E-5′-nucleotidase), and ecto-adenosine deaminase (E-ADA), is involved in the regulation and modulation of the physiological and pathological events linked to hemostasis. This occurs due to the role of adenosine diphosphate (ADP) in the activation and recruitment of platelets, and the role of adenosine (Ado) in the inhibition of platelet activation. Thus, here we aimed to evaluate whether Aeromonas caviae infection impairs the ecto-enzymes of the purinergic system in fish thrombocytes and the involvement of this system in the hemorrhagic septicemia. The total number of fish thrombocytes decreased in infected animals compared to uninfected animals. Regarding the ecto-enzymes of the purinergic system, the E-NTPDase and E-5′-nucleotidase activities increased in infected animals compared to uninfected animals, while the E-ADA activity decreased. These findings show that adenine nucleotide hydrolysis is modified in the thrombocytes of fish experimentally infected with A. caviae, which impairs the coagulation process due the excessive hydrolysis of ADP, a molecule linked with activation and recruitment of thrombocytes at the site of vascular injury, and augmentation on Ado levels, a molecule linked with inhibitory effects on platelet activation and aggregation. In summary, the purinergic system might contribute to the occurrence of hemorrhagic frames in fish infected with A. caviae.

Nanoencapsulated Melaleuca alternifolia essential oil (tea tree oil, TTO) is a natural alternative treatment, with 100% therapeutic efficacy in fish experimentally infected with Pseudomonas aeruginosa, and has also potent protective effects linked with antioxidant properties. However, the pathways responsible for the antioxidant capacity remain unknown. Thus, this study evaluated whether the inhibition of seric xanthine oxidase (XO) activity can be considered a pathway involved in the antioxidant capacity of nanoencapsulated TTO in fish experimentally infected with P. aeruginosa. Seric samples from fish infected with P. aeruginosa showed increased XO activity, as well as increased uric acid and reactive oxygen species (ROS) levels. In contrast, the prophylactic treatment with nanoencapsulated TTO prevented these infection-induced alterations. Based on the evidence obtained, the upregulation of seric XO activity induced pro-oxidative effects in the serum of fish experimentally infected with P. aeruginosa, due to excessive formation of uric acid, which stimulates the release of ROS. This treatment was able to prevent the upregulated seric XO activity and, consequently, the excessive formation of uric acid and ROS. In summary, inhibition of seric XO activity can be considered a pathway involved in the antioxidant capacity of nanoencapsulated TTO in fish experimentally infected with P. aeruginosa.

It has been recognized that the cholinergic and adenosinergic systems, through the enzymes acetylcholinesterase (AChE) and adenosine deaminase (ADA), exert an important role in the immune and inflammatory responses during bacterial fish diseases. The immune response against Aeromonas caviae remains poorly understood, and the involvement of these systems, through the anti-inflammatory molecules acetylcholine (ACh) and adenosine (Ado), has not been studied. Thus, the aim of this study was to evaluate the involvement of cholinergic and adenosinergic systems on the inflammatory and immune responses in peripheric and splenic lymphocytes of fish experimentally infected with A . caviae . AChE and ADA activities in peripheric and splenic lymphocytes increased in infected animals on day 4 post-infection compared to uninfected animals, while the ACh and Ado levels decreased. Moreover, spleen histopathology revealed an increase in the number of melano-macrophage centers, as well as lipid inclusions and cellular debris in the ellipsoids. This evidence indicates that infection by A . caviae alters the cholinergic and adenosinergic systems, suggesting the involvement of AChE and ADA activities in the impairment of the immune system, since infection leads to a reduction in ACh and Ado levels, respectively. In summary, the upregulation of AChE and ADA activities in peripheric and splenic lymphocytes exerts a pro-inflammatory profile, contributing to systemic and tissue inflammatory damage, and consequently to disease pathogenesis.

In this manuscript, we report, the photophysical study of triplet excited states and antimicrobial photoinactivation of positively charged tetra-cisplatin porphyrin derivatives against Gram + and Gram ‒ bacterial strains. Isomeric cisplatin-porphyrins were used and applied in aPDT assays in the bacilli Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa (Gram negative) and a cocci Staphylococcus aureus (Gram positive) strains. The results show that compound substituted at meta position (3-cis-PtTPyP) is the more efficient photosensitizer against bacteria culture. In this way, tetra-cationic porphyrins containing cisplatin derivatives might be promising aPDT agents with potential applications in clinical infections.

Soybeans in Brazil stand out as the major grain grown throughout the country, being economically and socially essential. However, there are several limiting factors for its production such as diseases caused by nematodes, mainly the species of the genus Meloidogyne sp. that prevent the production in infested areas. In order to find new alternatives for the protection and control of such disease, the following study aimed to determine the nematicidal activity of Melaleuca alternifolia oil in its pure form and solid lipid nanocarriers containing the oil. It was found that both the pure essential oil and its nanostructured form presented nematicidal potential in vitro and in vivo , however, at different times of action. All concentrations were active and similar regarding action to abamectin, the conventional treatment. In this sense, this paper for the first time presents the action of M . alternifolia nanoparticles in the treatment/prevention of infections by Melodogyne sp.

Microbial biofilms represent a challenge in the treatment of infections, due to the low efficacy of the antimicrobials. This study evaluated the antimicrobial effect of nanoparticles of Melaleuca alternifolia (TTO) in dental biofilm. Thirty-eight volunteers used an oral device in situ in situ including four bovine enamel specimens for 07 days. From the fifth day four solutions were applied randomly for each specimen: Physiological Saline Solution (0.85% NaCl) (C+), Chlorhexidine 0.12% (CHX), M. alternifolia oil 0.3% (TTO), and a nanoparticle solution of 0.3% M. alternifolia oil (NPTTO). The nanoparticles of TTO were characterized for pH, IPD, medium size, zeta potential and Transmission Electron Microscopy. Antimicrobial activity was evaluated by viable microorganisms count and the structure of the biofilm by atomic force microscopy. The NPTTO presented pH 6.4, particle diameter of 197.9 ± 1 nm, polydispersion index of 0.242 ± 0.005, zeta potential of −7.12 mV and ±0:27 spherical shape. The C+ resulted in 100% of bacterial vitality, while CHX, TTO and NPTTO showed 34.2%, 51.4% and 25.8%, respectively. The AFM images showed biofilms with an average roughness of 350 nm for C+, 275 nm for CHX, 500 nm for TTO and 100 nm for NPTTO. The NPTTO demonstrated excellent antimicrobial activity in the biofilm formed in situ and will possibly be used in future for the treatment/prevention of oral biofilms.

Several studies have been demonstrated that phosphotransfer network, through the adenylate kinase (AK) and pyruvate kinase (PK) activities, allows for new perspectives leading to understanding of disease conditions associated with disturbances in energy metabolism, metabolic monitoring and signalling. In this sense, the aim of this study was to evaluate whether experimental infection by Aeromonas caviae alters hepatic AK and PK activities of silver catfish Rhamdia quelen. Hepatic AK and PK activities decreased in infected animals compared to uninfected animals, as well as the hepatic adenosine triphosphate (ATP) levels. Also, a severe hepatic damage was observed in the infected animals due to the presence of dilation and congestion of vessels, degeneration of hepatocytes and loss of liver parenchyma architecture and sinusoidal structure. Therefore, we have demonstrated, for the first time, that experimental infection by A. caviae inhibits key enzymes linked to the communication between sites of ATP generation and ATP utilization. Moreover, the absence of a reciprocal compensatory mechanism between these enzymes contributes directly to hepatic damage and for a severe energetic imbalance, which may contribute to disease pathophysiology.

Cytosolic and mitochondrial creatine kinases (CK), through the creatine kinase-phosphocreatine (CK/PCr) system, provide a temporal and spatial energy buffer to maintain cellular energy homeostasis. However, the effects of bacterial infections on the kidney remain poorly understood and are limited only to histopathological analyses. Thus, the aim of this study was to investigate the involvement of cytosolic and mitochondrial CK activities in renal energetic homeostasis in silver catfish experimentally infected with Aeromonas caviae. Cytosolic CK activity decreased in infected animals, while mitochondrial CK activity increased compared to uninfected animals. Moreover, the activity of the sodium-potassium pump (Na+, K+-ATPase) decreased in infected animals compared to uninfected animals. Based on this evidence, it can be concluded that the inhibition of cytosolic CK activity by A. caviae causes an impairment on renal energy homeostasis through the depletion of adenosine triphosphate (ATP) levels. This contributes to the inhibition of Na+, K+-ATPase activity, although the mitochondrial CK activity acted in an attempt to restore the cytosolic ATP levels through a feedback mechanism. In summary, A. caviae infection causes a severe energetic imbalance in infected silver catfish, which may contribute to disease pathogenesis.

Pelargonium graveolens is a member of the Geraniaceae family and has been used in folk medicine in many countries because of its anti-inflammatory activity. No studies have yet been reported to evaluate the anti-inflammatory activity of a nanoemulsion containing geranium oil (GO) model in macrophages. In this study the anti-inflammatory effect of Geranium nanoemulsion (NEG) macrophages induced with soluble proteins of Candida albicans was investigated. GO presented citronellol (17.74%) and geraniol (14.43%) as main constituents. The characterization in NEG was demonstrated, showing the particle size of 164 ± 3.5 nm, PDI of 0.12 ± 0.006 and zeta potential −10 mV ± 1.7. The MIC obtained for NEG and GO were 3.64 μg ml −1 and 1.82 μg ml −1 , respectively. The viability of the macrophages treated with NEG and GO concentrations (1/2 x, 1x and 2x MIC) was evaluated. There was a significant reduction of viability and the MTT assay was not confirmed after the LDH assay. Anti-inflammatory activity was evaluated by determining nitric oxide (NO), cytokines (interleukin IL-1, IL-6 and IL-10), tumor necrosis factor-α (TNF) and the expression levels gene of interleukin (IL-2), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). The apoptosis inhibition capacity was assessed by determination of INFγ, caspase 3 and caspase 8. The results indicated that there was a significant increase of NO in the levels after treatment with NEG and significantly reduced levels after treatment with GO. The cytokines (IL-1, IL-6, IL-10, and TNF) were evaluated and NEG (½ x, 1x MIC) decreased IL-1 levels by 1.25–1.37 times, respectively. The NEG did not decrease IL-6 levels and a significant increase was observed for IL-10. GO significantly decreased IL-6 and IL-10 levels. There was a significant decrease in IL-2 and COX-2 levels and increased levels of iNOs. The levels of IFNγ and caspase-3 after treatment with NEG decreased indicating an anti-inflammatory effect and can inhibit apoptosis. Finally, the levels of caspase-8 do not change. Thus, pretreatment with NEG induced an anti-inflammatory effect against soluble proteins of C. albicans model macrophages.

Candida infection is an important cause of morbidity and mortality on immunosuppressed patients. This growing trend has been associated with resistance to the antimicrobial therapy and the ability of microorganism to form biofilms. TTO oil is used as antimicrobial which shows antibiofilm activity against Candida species. However, it presents problems due to its poor solubility and high volatility. The present study aimed to evaluate in vitro antibiofilm activity of TTO nanoparticles against many Candida species. It was performed the characterization of the oil and nanoparticles. The levels of exopolysaccharides, proteins, and the biomass of biofilms were measured. The chromatographic profile demonstrated that the TTO oil is in accordance with ISO 4730 with major constituents of 41.9% Terpinen-4-ol, 20.1% of γ-Terpinene, 9,8% of α-Terpinene, and 6,0% of 1,8-Cineole. The TTO nanoparticles showed pH of 6.3, mean diameter of 158.2 ± 2 nm, polydispersion index of 0.213 ± 0.017, and zeta potential of -8.69 ± 0.80 mV. The addition of TTO and its nanoparticles represented a significant reduction of biofilm formed by all Candida species, as well as a reduction of proteins and exopolysaccharides levels. It was possible to visualize the reduction of biofilm in presence of TTO nanoparticles by Calcofluor White method.

Laboratory evidence has demonstrated the antimicrobial effect of Melaleuca alternifolia (MEL) against oral microorganisms. This randomized, double-blind, crossover clinical trial, compared the anti-biofilm and anti-inflammatory effects of MEL nanoparticles with 0.12% chlorhexidine gluconate (CHX) on biofilm-free (BF) and biofilm-covered (BC) surfaces. Before each experimental period, the participants refrained from all oral hygiene practices for 72 hours. The 60 participants were randomly assigned to professional prophylaxis in two quadrants (Q1–Q3 or Q2–Q4), and rinsed with MEL or CHX for four days. The Quigley & Hein plaque index (QHPI), gingival crevicular fluid (GCF) volume, and participants’ perceptions were assessed. CHX showed significantly lower mean QHPI on BF (2.65 ± 0.34 vs. 3.34 ± 0.33, p < 0.05) and BC surfaces (2.84 ± 0.37 vs. 3.37 ± 0.33, p < 0.05). Intragroup comparisons indicated reductions in GCF in all the groups, with significant differences only for CHX on BF surfaces (p < 0.05). Intergroup comparisons revealed no significant differences (p > 0.05). Based on individual perceptions, CHX had better taste and biofilm control, but resulted in a greater change in taste. Nevertheless, MEL demonstrated anti-inflammatory effects similar to those of CHX. Further clinical trials testing different protocols, concentrations and follow-up periods are required to establish its clinical application.

Highlights • Rapidly growing mycobacteria (RGM) causing infections by biofilm formation. • Semi-quantitative method of biofilm formation was adapted for macrotechnics. • Sulphonamides complexed with metals is a promising anti-adhesion agent. • Sulphonamides complexed with metal is a possible inhibitor of signaling of biofilm formation., Rapidly growing mycobacteria (RGM) are found in non-sterile water and often associated with severe post-surgical infections and affect immunocompromised patients. In addition, RGM can prevent the host's immune response and have the ability to adhere to and form biofilms on biological and synthetic substrates, making pharmacological treatment difficult because conventional antimicrobials are ineffective against biofilms. Thus, there is an urgent need for new antimicrobial compounds that can overcome these problems. In this context, sulfonamides complexed with Au, Cd, Ag, Cu, and Hg have shown excellent activity against various microorganisms. Considering the importance of combating RGM-associated infections, this study aimed to evaluate the activity of sulfonamide metal complexes against RGM biofilm. The sulfonamides were tested individually for their ability to inhibit mycobacterial formation and destroy the preformed biofilm of standard RGM strains, such as Mycobacterium abscessus, M. fortuitum, and M. massiliense. All sulfonamides complexed with metals could reduce, at subinhibitory concentrations, the adhesion and biofilm formation of three RGM species in polystyrene tubes. It is plausible that the anti-biofilm capacity of the compounds is due to the inhibition of c-di-GMP synthesis, which is an important signal for RGM biofilm formation. Hence, the impacts and scientific contribution of this study are based on the discovery of a potential new therapeutic option against RGM-associated biofilm infections. Sulfonamides complexed with metals have proven to be a useful and promising tool to reduce microbial adhesion on inert surfaces, stimulating the improvement of methodologies to insert compounds as new antibacterial and coating agents for medical and hospital materials.

The aim of this study was to evaluate the in vitro susceptibility of larva and adult forms of Alphitobius diaperinus treated with cinnamon (Cinnamomum zeylanicum) essential oil on its free form, nanoemulsion (NE), and nanocapsule (NC), as well as the effect of these treatments on the edaphic fauna using springtails of Folsomia candida (ISO) as a model. The tests with larvae and adults were performed using 1, 5, and 10% of the cinnamon essential oil, and 0.5, 1, and 5% of NE and NC containing 5% of cinnamon essential oil. To validate the test, three controls were used: only oil diluent (Triton), blank nanoemulsion (without oil) and blank nanocapsule (without oil). Cinnamon essential oil at 5 and 10% caused mortality in larva and adult forms of A. diaperinus. The NE (1%) and NC (5%) caused mortality in both phases of A. diaperinus life cycle. After these promising findings, more studies were conducted to verify the ecotoxicological effect of the cinnamon oil. For this, a Tropical Artificial Soil (TAS) was used with different doses of cinnamon oil, NE and NC, using springtails of F. candida. The use of cinnamon oil, even in very low concentrations (25 mg kg− 1), on its original form significantly affected springtails survival and reproduction. However, the nanostructuring process seemed to minimize this toxic effect without affecting its insecticidal action. In summary, the pure oil and NE containing cinnamon oil showed effect against A. diaperinus, and may be considered an alternative to control this infestation.

Graphical abstract, The acaricidal effect of seven essential oils was examined in vitro against the cattle tick (Rhipicephalus microplus). Engorged female ticks were manually collected in farms of Southern Brazil and placed into petri dishes (n = 10) in order to test the following oils: juniper (Juniperus communis), palmarosa (Cymbopogon martinii), cedar (Cedrus atlantica), lemon grass (Cymbopogon citratus), ginger (Zingiber officinale), geranium (Pelargonium graveolens) and bergamot (Citrus aurantium var bergamia) at concentrations of 1%, 5%, and 10% each. A control group was used to validate the tests containing Triton X-100 only. Treatment effectiveness was measured considering inhibition of tick oviposition (partial or total), egg’s weight, and hatchability. C. martinii, C. citratus and C. atlantica essential oils showed efficacy higher than 99% at all concentrations tested. In addition, J. communis, Z. officinale, P. graveolens, and C. aurantium var bergamia oils showed efficiency ranging from 73% to 95%, depending on the concentration tested, where higher concentrations showed greater efficacy. It was concluded that essential oils can affect tick reproduction in vitro by inhibiting oviposition and hatchability.

Infections due to microbial biofilm formation on the surface of catheters and other medical devices are constantly reported as a major cause of morbidity and mortality in patients admitted to hospitals. Furthermore, sessile cells are more resistant to phagocytosis and most antimicrobial, which complicates the treatment of such infections. Researches aimed at new antimicrobial originating mainly from plants have increased in recent years and the development of new strategies for their release is critical in combating the formation of biofilms. Geranium oil (GO) has proven antimicrobial activity. Because of this, the aim of this study was to develop nanoemulsions containing this oil (NEG) and evaluate its activity after the biofilm formation of Candida albicans, Candida tropicalis, Candida glabrata, and Candida krusei in hospital medical supplies. For quantification of the biofilm, crystal violet, total protein, and ATP-bioluminescence assays were used. The results revealed that GO and NEG showed lower MIC for C. albicans and C. tropicalis. The biofilms formed by different species of Candida on the surfaces of polyethylene and polyurethane were quantified. GO and NEG significantly inhibited the formation of biofilms in all species tested on the surfaces of polyethylene. However, NEG antibiofilm has had better activity than GO for C. albicans, C. tropicalis and C. glabrata, according to the surface potential analysis by atomic force microscopy (AFM). The analysis of the biofilm formation on the polyethylene surface by ATP-bioluminescence and CFU showed similar results. In both methods the formation of biofilm in the catheter occurred in greater quantity for C. albicans and C. tropicalis. GO did not significantly inhibit the formation of biofilms only in C. krusei, although NEG significantly increased this activity GO in all species tested when compared to the control training biofilm. The following study shows that the development of NEG may become an effective alternative to reduce the adhesion of microorganisms and prevent infections resulting from the use of some hospital medical materials.

The Pseudomonas aeruginosa is a gram-negative bacillus and frequent cause of infection. This microorganism is resistant intrinsically to various drugs. The P. aeruginosa is associated with the biofilm formation, which causes worsen the prognosis and difficulty the treatment. The influence of Melaleuca alternifolia oil or "tree of tee" oil (TTO) and TTO nanoparticles on adhesion of P. aeruginosa in buccal epithelial cells was investigated. Also was determined the antimicrobial and antibiofilm activity against this microorganism. The TTO nanoparticles were produced by deposition of preformed polymer and the physic-chemical properties of nanoparticles were measured by electrophoresis and dynamic light scattering. The characterization of nanoparticle showed acceptable values for diameter and zeta potential. The evaluation of antimicrobial and antibiofilm activity against P. aeruginosa PAO1 was performed by microdilution indicating the minimal inhibitory concentration, and the potential antibiofilm. It was verified the action on virulence factors such the motility, besides the influence on adhesion in buccal epithelial cells. Both oil and nanoparticles showed a decrease in adhesion of microorganisms to buccal cells, decrease of biofilm and interfering on P. aeruginosa PAO1 motility. The nanostructuration of TTO, shows be a viable alternative against formed biofilm microorganisms.

Pseudomonas aeruginosa is one of the most important agent representing high mortality and significant economic losses in aquaculture. Due to growing reports of antimicrobial resistance, it is important to develop studies involving alternative therapies and new technologies, including the use of essential oils and nanotechnology. In this sense, the aim of this study was to evaluate whether Melaleuca alternifolia essential oil (TTO) exerts in vivo bactericidal action against P. aeruginosa strain PA01, as well as to evaluate whether nanotechnology is able to improve this action in experimentally infected Rhamdia quelen. Our results demonstrated that free TTO and nanoencapsulated TTO exert potent bactericidal action against P. aeruginosa. The most important finding is that TTO nanoparticles possess 100% of curative efficacy, while free TTO possesses 70% of curative efficacy. In summary, the nanoencapsulation of TTO was able to improve the bactericidal action of TTO, and may be considered an important approach to prevent and/or treat infected animals with P. aeruginosa.

In this work, we report the antimicrobial photoinactivation using tetra-cationic porphyrins with peripheral palladium(II) complexes against bacterial strains. Two different isomeric Pd(II)-porphyrins were used and applied in PDI experiments in the strains Gram negative bacilli Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa and a Gram positive cocci Staphylococcus aureus. All experiments are conducted with adequate concentration (without aggregation) of photosensitizer under white-light irradiation over 2 h . We showed that the most effective PS caused a significative reduction in the concentration of viable bacteria. The present results show that porphyrin with positively charge at meta position (3-PtTPyP) are more efficient photosensitizer against bacteria strains. In this way, tetra-cationic porphyrins might be promising antibacterial PDI agents with potential applications in clinical cases.

The objective of this study was to evaluate the antifungal activity of eucalyptus (Eucalyptus globulus) and lemongrass (Cymbopogon flexuosus) essential oils in their free and nanoemulsion forms in the murine model of vulvovaginal candidiasis (VVC). The nanoemulsions were developed by the homogenization method under high agitation and characterized according to the mean droplet size, polydispersity index, zeta potential, and pH. The murine VVC model was induced in BALB/c mice by the administration of estradiol valerate preceding the Candida albicans challenge. Nanoemulsions containing eucalyptus or lemongrass oils showed average droplet size of less than 100 nm, a polydispersity index about 0.2, negative zeta potential, and acidic pH. For in vivo treatment of VVC, the essential oils in their free form did not show antifungal activity, while the two nanoemulsions were able to reduce the fungal load similarly or better than the control animal group treated with miconazole cream. The results obtained in this study demonstrated that the use of nanoemulsions containing eucalyptus or lemongrass essential oils could be a promising alternative to be used as a proof of concept to develop a new therapy for the treatment of VVC.

For the first time, the repellent and insecticidal effects of eucalypt essential oil (Eucalyptus globulus) in its free form and associated with different nanostructures (nanoemulsion and nanocapsules) were investigated against Musca domestica (Diptera: Muscidae) and Haemotobia irritans (Diptera: Muscidae) flies. Specimens of M. domestica were collected, separated into groups (n = 10), treated with aspersion of essential oil of eucalypt in its free (1, 5, and 10%) and nanostructured (nanoemulsion or nanoencapsulated at 1, 3, and 5%, respectively) forms. The determination of the insecticidal effect was performed by counting the number of dead flies at intervals of 30, 60, 120, 360 and 750 min after oil aspersion. E. globulus essential oil showed insecticidal effect against M. domestica at concentrations of 1 and 5%. Eucalypt essential oil (10%) caused 100% mortality of M. domestica after 750 min of the treatment. Nanocapsules (3 and 5%) showed efficacy by reducing the number of flies. On the other hand, nanoemulsion did not show insecticidal effect. The repellent action of E. globulus concentrations of 5% was tested against H. irritans on naturally infested cows. The repellent action against H. irritans was verified soon after pulverization. After 24 h, a significant reduction on horn flies' population (83.33 and 66.66%) was observed using free and nanoencapsulated forms tested, respectively. E. globulus essential oil demonstrated insecticidal and repellent effects against M. domestica and H. irritans flies.

The main objective of this study was to demonstrate the antimicrobial potential of the crude extract and fractions of Chenopodium ambrosioides L., popularly known as Santa-Maria herb, against microorganisms of clinical interest by the microdilution technique, and also to show the chromatographic profile of the phenolic compounds in the species. The Phytochemical screening revealed the presence of cardiotonic, anthraquinone, alkaloids, tannins and flavonoids. The analysis by HPLC-DAD revealed the presence of rutin in the crude extract (12.5 ± 0.20 mg/g), ethyl acetate (16.5 ± 0.37 mg/g) and n-butanol (8.85 ± 0.11 mg/g), whereas quercetin and chrysin were quantified in chloroform fraction (1.95 ± 0.04 and 1.04 ± 0.01 mg/g), respectively. The most promising results were obtained with the ethyl acetate fraction, which inhibited a greater number of microorganisms and presented the lowest values of MIC against Staphylococcus aureus and Enterococcus faecalis (MIC = 0.42 mg/mL), Pseudomonas aeruginosa (MIC = 34.37 mg/mL), Paenibacillus apiarus (MIC = 4.29 mg/mL) and Paenibacillus thiaminolyticus (MIC = 4.29 mg/mL). Considering mycobacterial inhibition, the best results were obtained by chloroform fraction against M. tuberculosis, M. smegmatis, and M. avium (MIC ranging from 156.25 to 625 µg/mL). This study proves, in part, that the popular use of C. ambrosioides L. can be an effective and sustainable alternative for the prevention and treatment of diseases caused by various infectious agents.

Astrocaryum aculeatum, popularly known as tucuma, belongs to Arecaceae family and is also called tucuma-do-amazonas, tucumanzeiro, tucuma-grande, or tucuma-accu. This palm tree is native to the Amazon, occurring in northern Bolivia, Colombia, Venezuela, Guyana, Suriname, and Brazil being found mainly in the state of Amazonas. It is a large palm tree, with an upright stipe of 10–30 m, being covered in its upper half by black or brown thorns arranged in rings. The leaves have a feather shape and have thorns on its entire length, measuring 4–5 m long. The productivity of the palm tree is around 12–50 kg/year, which starts slowly and late, when the tree reaches 7 years at least with height between 6 and 9 m. The fruit weighs 20–100 grams and is yellowish-green, with a length of 4.5–6.0 and 3.5 cm–4.5 cm in diameter. The pulp has a coloration ranging from yellow to orange and has 9% protein, 55% oil, and represents 22% of the fruit weight. A number of substances have been identified: carotenoids (62.6 mg/g of fresh pulp), being 21 isoforms, with a predominance of 75% of all-trans beta-carotene; flavonoids like catechin and quercetin and ascorbic acid (58 mg/100 g). It is currently consumed by the Amazon population, with the use of nearly all the plants. The stipe is applied to the construction of houses and furniture. The meristem is used in food. The flesh of the fruit, which is the edible part, is widely used for the production of tucuma wine, ice cream, popsicles, soap, as well as animal feed. The core is used for the production of handicrafts, such as rings, bracelets, and necklaces. Furthermore, the core has been widely used to extract an oil to be used in the cosmetic and food industry, and in the production of biodiesel. The leaves have been used in the production of baskets, hats and Tucum (a high-quality fiber for the production of hammocks and bags) is extracted from them. Recent studies, suggest that the hydroalcoholic extract of tucuma has an antioxidant capacity quite high and also has some action in modulating the production of free radicals in healthy blood exposed to hydrogen peroxide. These results indicate that tucuma may have chemotherapeutic potential.

The present study aimed to genotypically and phenotypically characterize clinical isolates of carbapenem-resistant Enterobacteriaceae collected from inpatients at the University Hospital of Santa Maria, during seven months. Among the clinical isolates subjected to the modified Hodge test (MHT), 62.5% were positive, indicating possible production of carbapenemase. Polymerase chain reaction (PCR) demonstrated that blaKPC was the most frequently found gene (31%), followed by blaIMP (12.5%). Combined use of the methods is needed to identify carbapenem resistance in enterobacteria to prevent their spread and control the infections caused by these organisms. RESUMO Objetivou-se caracterizar fenotípica e genotipicamente isolados clínicos de enterobactérias resistentes aos carbapenêmicos (CRE) provenientes do Hospital Universitário de Santa Maria (RS). Entre os isolados clínicos submetidos ao teste modificado de Hodge (MHT), 62,5% apresentaram positividade, indicando possível produção de carbapenemase. A reação em cadeia da polimerase (PCR) demonstrou que o blaKPC foi o gene mais encontrado (31%), seguido de blaIMP (12,5%). O uso conjunto de distintas metodologias faz-se necessário para identificar a resistência aos carbapenêmicos produzida pelas enterobactérias, de modo a auxiliar o controle de infecção prevenindo a disseminação desses microrganismos.

The aim of this study was to verify in vitro the influence of rosemary, andiroba, and copaiba essential oils on different stages of the cattle tick Rhipicephalus microplus. Female ticks were collected from naturally infected cows and treated in vitro with these essential oils at concentrations of 5% and 10%. All tests were performed in triplicate using positive (amitraz 10%) and negative (untreated) controls. It was possible to observe that rosemary, andiroba, and copaiba essential oils inhibited female reproduction at concentrations of 5% (45.0%, 77.5%, and 71.6%, respectively) and 10% (55.7%, 92.0,% and 86.7%, respectively) compared with amitraz (72.9%). Additionally, andiroba (10%) and copaiba (5% and 10%) oil solutions also had an acaricidal effect (100%), similarly to the positive control. The andiroba and copaiba oils showed an ovicidal effect, which effected hatchability. Rosemary oil showed neither acaricidal nor ovicidal effect. Therefore, based on these results, we were able to show that all oil...

Our research aimed to test the effects of Melaleuca alternifolia oil (pure and in nanocapsules) in the control of Rhipicephalus microplus in dairy cattle. For this purpose, the in vivo studies used 15 cows distributed in three different groups with the same number of animals. Five cows remained untreated (Group A), representing the control group; other five cows were sprayed with TTO (at 5%) in its pure form (Group B); and five cows were sprayed with nanocapsules of TTO (at 0.75%) (Group C). On days 1 and 4 post-treatments (PT), all cows had their ticks counted. On day 1 PT, two ticks from each cow were collected to evaluate the effect of the treatment on ticḱs reproduction (in vitro assays). The pure form of TTO caused a significant reduction (P0.05) in the number of ticks from the Group B compared to the Group A on day 4 PT. However, there was no significant difference in the number of ticks on cows from Groups A and C after treatment (P0.05). Treatment with TTO in nanocapsules (Group C) interfered with R. microplus reproduction, leading to lower oviposition by female ticks and hatchability (34.5% of efficacy). On the other hand, TTO oil (Group B) did not interfere on ticḱs reproduction, i.e. showed higher hatchability than the control group. Therefore, it is possible to conclude that pure TTO has an acaricidal effect in dairy cows, in addition to an effect on ticḱs reproduction when used its nanocapsulated form.

Several pieces of evidence have linked the involvement of xanthine oxidase (XO), a source of uric acid and reactive oxygen species (ROS), to pro-oxidative and pro-inflammatory effects observed during bacterial fish diseases. Thus, the aim of this study was to evaluate whether upregulation of splenic XO activity contributes to disease pathogenesis of Aeromonas caviae infection, as well as whether it may be considered a pathway involved in ROS and nitric oxide (NO) production. XO activity increased in the spleen of infected animals, as did the splenic levels of uric acid, ROS and metabolites of nitric oxide (NOx), compared to the uninfected control group. Based on this evidence, upregulation of splenic XO activity induces pro-oxidant and pro-inflammatory profiles in the spleen of fish infected by A. caviae due to excessive formation of uric acid. Moreover, excessive uric acid induces the release of pro-inflammatory mediators, such as ROS and NOx, which contribute to disease pathophysiology. In summary, upregulation of XO activity may be considered a pathway involved in ROS and NOx production.

Candida species are the main responsible microorganisms for causing fungal infections worldwide, and Candida albicans is most frequently associated with infectious processes. Pseudomonas aeruginosa is a gram-negative bacterium commonly found in immunocompromised patients. The infection persistence caused by these microorganisms is often related to antimicrobial resistance and biofilm formation. In this context, the objective of the present study was to prepare and characterize nanoemulsions containing Eucalyptus globulus oil and to verify its antimicrobial and antibiofilm activities against P. aeruginosa and Candida spp. The nanoemulsions had a size of approximately 76 nm, a polydispersity index of 0.22, a zeta potential of – 9,42 mV and a pH of approximately 5.0. The E. globulus oil was characterized by gas chromatography, being possible to observe its main components, such as 1-8-Cineol (75.8%), p- Cymene (7.5%), α-Pinene (7.4%) and Limonene (6.4%). The antimicrobial activity of the nanoemulsion was determined from the macrodilution tests and the cell viability curve, where the minimum fungicidal concentration of 0.7 mg/mL for C. albicans and 1.4 mg/mL for C. tropicalis and C. glabrata were obtained. However, the nanoemulsions did not present antimicrobial activity against P. aeruginosa , since it contains only 5% of the oil, being ineffective for this microorganism. The nanoencapsulated oil action against the formed biofilm was evaluated by atomic force microscopy and calcofluor staining, and the nanoemulsion was more efficient for two of the three Candida species when compared to free oil.

Central nervous system (CNS) infections continue to be an important cause of morbidity and mortality, and microbial invasion of the blood–brain barrier (BBB) is considered a prerequisite for CNS infections, which contribute to behavioural abnormalities and disease pathogenesis. Based on this information, the aim of this study was to evaluate whether Pseudomonas aeruginosa causes disruption of the BBB, and to investigate the involvement of cerebral myeloperoxidase (MPO) activity in this process in experimentally infected silver catfish. The permeability of the BBB to Evans blue dye increased in the infected animals on days three and six post-infection (PI) compared to the control group. Moreover, cerebral MPO activity and reactive oxygen species (ROS) levels also increased in the infected animals on days three and six PI compared to the control group. Based on this evidence, we concluded that P. aaeruginosa causes a disruption of the BBB, which may contribute to disease pathogenesis in the CNS. Moreover, the increase in cerebral MPO activity and ROS levels may be considered a pathway involved in BBB breakdown, allowing the passage of bacteria to the CNS.

Background The present study aimed to evaluate the possible acute oral toxicity of Baccharis trimera leaf dye as well as its antimicrobial activity. Method Organization for Economic co-operation and development (OECD) 423 was used to assess acute oral toxicity and as per protocol a dose of 2000 mg/kg of tincture was administered to Wistar rats, male and female, and observed for 14 days. Biochemical and hematological analyzes were performed with sample collected of rat. The dye was evaluated for antimicrobial activity by agar diffusion and microdilution methods, which allow to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) and antibiofilm potential. Results The results showed that there was no loss of animals and no significant changes in hematological and biochemical parameters after oral administration of 2000 mg/kg of tincture and was considered safe by the OECD, classified as category 5. The dyeing also showed an important antimicrobial activity against gram positive and gram negative bacteria also significantly decreased the microbial biofilm. Conclusion The tincture of B. trimera leaf when given orally once can be considered safe and has a relevant antimicrobial potential that should be elucidated in subsequent research.