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Encapsulation techniques are generally used to preserve the volatile compounds of essential oils. This study aimed to evaluate the influence of process variables on the microencapsulation of marjoram essential oil (MEO) (Origanum majorana L.) by ionic gelation. The effect of sodium alginate concentration (0.5-2 g/100 mL), emulsifier concentration (0.5-2 g/100 mL whey protein isolate (WPI)), and cationic bath concentration (0.05-0.3 mol/L CaCl2) on the emulsions and beads properties were investigated, according to a rotatable central composite design. MEO chemical composition and antimicrobial activity were assessed. Emulsions were characterized for droplet size and viscosity, while the particles were analyzed for encapsulation efficiency, size and circularity, and morphology. High concentrations of alginate and WPI intensified the porous structure of the beads, reducing droplet mean diameter and encapsulation efficiency. High alginate concentrations also increased emulsion viscosity, affecting positively beads' circularity. The intermediate concentration of sodium alginate (1.25 g/100 mL), WPI (1.25 g/100 mL), and CaCl2 (0.175 mol/L) were selected as the most appropriate conditions to produce beads with satisfactory circularity and high encapsulation efficiency.
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Óleos Voláteis , Origanum , Proteínas do Soro do Leite/química , Emulsões/química , Alginatos/química , Aditivos Alimentares , Óleos Voláteis/farmacologia , Cloreto de CálcioRESUMO
Brazilian medical mycology considerably expanded in the last decades due to the efforts of several pioneers who started and expanded mycology during the twentieth century. In this manuscript, we highlight some of the contributions of one of these pioneers: Professor Luiz R. Travassos, who started his career in the field of microbiology in the 1960s. We will discuss his contributions to the areas of medical mycology and glycobiology, with a focus on glycosphingolipids, sialic acids, and surface enzymes.
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Micologia , Micologia/história , BrasilRESUMO
Leishmaniasis is a vector-borne disease against which there are no approved vaccines, and the treatment is based on highly toxic drugs. The alkaloids consist of a chemical class of natural nitrogen-containing substances with a long history of antileishmanial activity. The present study aimed at determining the antileishmanial activity and in silico pharmacokinetic and toxicological potentials of tryptanthrin alkaloid. The anti-Leishmania amazonensis and anti-L. infantum assays were performed against both promastigotes and intracellular amastigotes. Cellular viability was determined by parasites' ability to grow (promastigotes) or differentiate (amastigotes) after incubation with tryptanthrin. The mechanisms of action were explored by mitochondrion dysfunction and apoptosis-like death evaluation. For the computational pharmacokinetics and toxicological analysis (ADMET), tryptanthrin was submitted to the PreADMET webserver. The alkaloid displayed anti-promastigote activity against L. amazonensis and L. infantum (IC50 = 11 and 8.0 µM, respectively). Tryptanthrin was active against intracellular amastigotes with IC50 values of 75 and 115 µM, respectively. Mitochondrial membrane depolarization was observed in tryptanthrin-treated promastigotes. In addition, parasites undergoing apoptosis-like death were detected after 18 h of exposure. In silico ADMET predictions revealed that tryptanthrin has pharmacokinetic and toxicological properties similar to miltefosine. The results presented herein demonstrate that tryptanthrin is an interesting drug candidate against leishmaniasis.
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Sulphate-reducing bacteria (SRB) cause fouling, souring, corrosion and produce H2S during oil and gas production. Produced water obtained from Periquito (PQO) and Galo de Campina (GC) onshore oilfields in Brazil was investigated for SRB. Produced water with Postgate B, Postgate C and Baars media was incubated anaerobically for 20 days. DNA was extracted, 16S rDNA PCR amplified and fragments were sequenced using Illumina TruSeq. 4.2 million sequence reads were analysed and deposited at NCBI SAR accession number SRP149784. No significant differences in microbial community composition could be attributed to the different media but significant differences in the SRB were observed between the two oil fields. The dominant bacterial orders detected from both oilfields were Desulfovibrionales, Pseudomonadales and Enterobacteriales. The genus Pseudomonas was found predominantly in the GC oilfield and Pleomorphominas and Shewanella were features of the PQO oilfield. 11% and 7.6% of the sequences at GC and PQO were not classified at the genus level but could be partially identified at the order level. Relative abundances changed for Desulfovibrio from 29.8% at PQO to 16.1% at GC. Clostridium varied from 2.8% at PQO and 2.4% at GC. These data provide the first description of SRB from onshore produced water in Brazil and reinforce the importance of Desulfovibrionales, Pseudomonadales, and Enterobacteriales in produced water globally. Identifying potentially harmful microbes is an important first step in developing microbial solutions that prevent their proliferation.
Assuntos
Microbiota , Campos de Petróleo e Gás , Sulfatos/química , Microbiologia da Água , Biodiversidade , Biofilmes , Biotecnologia , Brasil , DNA Ribossômico/metabolismo , Bases de Dados Genéticas , Desulfovibrionales/genética , Ecologia , Enterobacteriaceae/genética , Gammaproteobacteria/genética , Geografia , Sulfeto de Hidrogênio/química , RNA Ribossômico 16S/genética , ÁguaRESUMO
Alcaligenes faecalis is a Gram-negative rod that is ubiquitous in the environment and is an opportunistic human pathogen. Here, we report the whole-genome sequencing analysis of A. faecalis HZ01, which presents mycobacterial growth inhibitory activity and was isolated from a contaminated culture of Mycobacterium chubuense ATCC 27278.
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Euterpe oleracea Mart. (Arecaceae) is an endogenous palm tree from the Amazon region. Its seeds correspond to 85% of the fruit's weight, a primary solid residue generated from pulp production, the accumulation of which represents a potential source of pollution and environmental problems. As such, this work aimed to quantify and determine the phytochemical composition of E. oleracea Mart. seeds from purple, white, and BRS-Pará açaí varieties using established analytical methods and also to evaluate it as an eco-friendly corrosion inhibitor. The proanthocyanidin quantification (n-butanol/hydrochloric acid assay) between varieties was 6.4-22.4 (w/w)/dry matter. Extract characterization showed that all varieties are composed of B-type procyanidin with a high mean degree of polymerization (mDP ≥ 10) by different analytical methodologies to ensure the results. The purple açaí extract, which presented 22.4% (w/w) proanthocyanidins/dry matter, was tested against corrosion of carbon steel AISI 1020 in neutral pH. The crude extract (1.0 g/L) was effective in controlling corrosion on the metal surface for 24 h. Our results demonstrated that the extracts rich in polymeric procyanidins obtained from industrial açaí waste could be used to inhibit carbon steel AISI 1020 in neutral pH as an abundant, inexpensive, and green source of corrosion inhibitor.
Assuntos
Euterpe/química , Proantocianidinas/farmacologia , Aço/química , Corrosão , Química Verde , Extratos Vegetais/química , Proantocianidinas/química , Sementes/químicaRESUMO
Sporotrichosis has become an important zoonosis in Brazil, and Sporothrix brasiliensis is the primary species transmitted by cats. Improvement of animal treatment will help control and limit the spread and geographic expansion of sporotrichosis. Accordingly, buparvaquone, an antiprotozoal hydroxynaphthoquinone agent marketed as Butalex, was evaluated in vitro and in vivo against feline-borne isolates of S. brasiliensis. Buparvaquone inhibited in vitro fungal growth at concentrations 4-fold lower than itraconazole (the first-choice antifungal used for sporotrichosis) and was 408 times more selective for S. brasiliensis than mammalian cells. Yeasts treated with a subinhibitory concentration of buparvaquone exhibited mitochondrial dysfunction, reactive oxygen species and neutral lipid accumulation, and impaired plasma membranes. Scanning electron microscopy images also revealed buparvaquone altered cell wall integrity and induced cell disruption. In vivo experiments in a Galleria mellonella model revealed that buparvaquone (single dose of 5 mg/kg of body weight) is more effective than itraconazole against infections with S. brasiliensis yeasts. Combined, our results indicate that buparvaquone has a great in vitro and in vivo antifungal activity against S. brasiliensis, revealing the potential application of this drug as an alternative treatment for feline sporotrichosis.
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Sporothrix , Esporotricose , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Gatos , Testes de Sensibilidade Microbiana , Naftoquinonas , Esporotricose/tratamento farmacológicoRESUMO
Cocos nucifera L. is a palm tree (Arecaceae) with a high economic value. The coconut husk fibers are nonedible, thick, and abrasion-resistant and correspond up to 85% of biomass discarded as solid waste residue. Therefore, the husk fibers are an underexploited byproduct with a high content of extractives of unreported nature. Two varieties of C. nucifera L. husk extracts were investigated to uncover bioactive metabolites and their possible application as a green corrosion inhibitor for carbon steel AISI 1020 under neutral pH conditions. The chemical analysis indicated 3% (w/w) of proanthocyanidins in the husk fibers with a high B-type procyanidin content. The husk fibers' crude extract showed promising results as an eco-friendly corrosion inhibitor for carbon steel AISI 1020 under neutral pH conditions. Although it formed a film on the metal surface in all tested concentrations (0.4, 0.8, 1.2, and 1.6 g L-1), the highest protective efficiency was shown at a concentration of 1.2 g L-1, determined by electrochemical techniques and mass loss. This was the first comprehensive report on coconut husk fibers' chemical composition, which was similar between the two varieties with potential for industrial application.
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Phialophora verrucosa causes several fungal human diseases, mainly chromoblastomycosis, which is extremely difficult to treat. Several studies have shown that human immunodeficiency virus peptidase inhibitors (HIV-PIs) are attractive candidates for antifungal therapies. This work focused on studying the action of HIV-PIs on peptidase activity secreted by P. verrucosa and their effects on fungal proliferation and macrophage interaction. We detected a peptidase activity from P. verrucosa able to cleave albumin, sensitive to pepstatin A and HIV-PIs, especially lopinavir, ritonavir and amprenavir, showing for the first time that this fungus secretes aspartic-type peptidase. Furthermore, lopinavir, ritonavir and nelfinavir reduced the fungal growth, causing remarkable ultrastructural alterations. Lopinavir and ritonavir also affected the conidia-macrophage adhesion and macrophage killing. Interestingly, P. verrucosa had its growth inhibited by ritonavir combined with either itraconazole or ketoconazole. Collectively, our results support the antifungal action of HIV-PIs and their relevance as a possible alternative therapy for fungal infections.
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Antifúngicos/farmacologia , Ácido Aspártico Proteases/antagonistas & inibidores , Inibidores da Protease de HIV/farmacologia , Macrófagos/efeitos dos fármacos , Phialophora/efeitos dos fármacos , Antifúngicos/síntese química , Antifúngicos/química , Ácido Aspártico Proteases/metabolismo , Carbamatos/síntese química , Carbamatos/química , Carbamatos/farmacologia , Relação Dose-Resposta a Droga , Furanos , Inibidores da Protease de HIV/síntese química , Inibidores da Protease de HIV/química , Humanos , Lopinavir/síntese química , Lopinavir/química , Lopinavir/farmacologia , Macrófagos/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Phialophora/enzimologia , Phialophora/crescimento & desenvolvimento , Ritonavir/síntese química , Ritonavir/química , Ritonavir/farmacologia , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/farmacologiaRESUMO
Lippia species share various pharmacological activities and are used in traditional cooking and medicine worldwide. Combined chromatographic techniques such as column chromatography, high-performance liquid chromatography, and countercurrent chromatography led to the purification of two new antifungal phenylpropanoid glycosides, lippiarubelloside A (1) and lippiarubelloside B (2), by bioactivity-directed fractionation of an ethanol-soluble extract from Lippia rubella, in addition to the known active related compounds forsythoside A (3), verbascoside (4), isoverbascoside (5), and poliumoside (6). The structures of compounds 1 and 2 were determined by comparison of their NMR spectroscopic data with the prototype active compound 4. Cryptococcus neoformans, which causes opportunistic lung infections, was sensitive to compounds 1-6 in the concentration range of 15-125 µg/mL. A synergistic effect (FICindex = 0.5) between 3 and amphotericin B was demonstrated. The glycosylated flavonoids pectolinarin (7), linarin (8), and siparunoside (9) were also isolated.
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Antifúngicos/farmacologia , Glicosídeos/farmacologia , Lippia/química , Fenilpropionatos/farmacologia , Antifúngicos/química , Candida/efeitos dos fármacos , Cryptococcus/efeitos dos fármacos , Glicosídeos/química , Fenilpropionatos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Análise Espectral/métodosRESUMO
BACKGROUND: The use of agro-industrial wastes to produce high value-added biomolecules such as biosurfactants is a promising approach for lowering the total costs of production. This study aimed to produce biosurfactants using Rhizopus arrhizus UCP 1607, with crude glycerol (CG) and corn steep liquor (CSL) as substrates. In addition, the biomolecule was characterized, and its efficiency in removing petroderivatives from marine soil was investigated. RESULTS: A 22 factorial design was applied, and the best condition for producing the biosurfactant was determined in assay 4 (3% CG and 5% CSL). The biosurfactant reduced the surface tension of water from 72 to 28.8 mN/m and produced a yield of 1.74 g/L. The preliminary biochemical characterization showed that the biosurfactant consisted of proteins (38.0%), carbohydrates (35.4%), and lipids (5.5%). The compounds presented an anionic character, nontoxicity, and great stability for all conditions tested. The biomolecule displayed great ability in dispersing hydrophobic substrates in water, thereby resulting in 53.4 cm2 ODA. The best efficiency of the biosurfactant in removing the pollutant diesel oil from marine soil was 79.4%. CONCLUSIONS: This study demonstrated the ability of R. arrhizus UCP1607 to produce a low-cost biosurfactant characterized as a glycoprotein and its potential use in the bioremediation of the hydrophobic diesel oil pollutant in marine soil
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Rhizopus/metabolismo , Tensoativos/metabolismo , Gasolina , Solo , Tensoativos/toxicidade , Tensão Superficial , Biodegradação Ambiental , Ambiente Marinho , Zea mays , Agroindústria , Interações Hidrofóbicas e Hidrofílicas , Glicerol , Resíduos Industriais , Micelas , Mucorales/metabolismoRESUMO
Piper is the largest genus of the Piperaceae family. The species of this genus have diverse biological activities and are used in pharmacopeia throughout the world. They are also used in folk medicine for treatment of many diseases in several countries including Brazil, China, India, Jamaica, and Mexico. In Brazil, Piper species are distributed throughout the national territory, making this genus a good candidate for biological activity screening. During our studies with Piper essential oils, we evaluated its activity against Rhizopus oryzae, the main agent of mucormycosis. The main compounds of seven Piper essential oils analyzed were Piper callosum-safrole (53.8%), P. aduncum-dillapiole (76.0%), P. hispidinervum-safrole (91.4%), P. marginatum-propiopiperone (13.2%), P. hispidum-γ-terpinene (30.9%), P. tuberculatum-(E)-caryophyllene (30.1%), and Piper sp.-linalool (14.6%). The minimum inhibitory concentration of Piper essential oils against R. oryzae ranged from 78.12 to >1250 µg/mL. The best result of total inhibition of biofilm formation was obtained with Piper sp. starting from 4.88 µg/mL. Considering the bioactive potential of EOs against planktonic cells and biofilm formation of R. oryzae could be of great interest for development of antimicrobials for therapeutic use in treatment of fungal infection.
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Fonsecaea pedrosoi is a dematiaceous fungus and the main causative agent of chromoblastomycosis that is a chronic disease usually affecting the human skin and subcutaneous tissues, which causes deformations and incapacities, being frequently refractory to available therapies. A typical globe-shaped, multiseptated and pigmented cells, known as sclerotic cells, are found in the lesions of infected individuals. In the present work, we have investigated the production of aspartic-type peptidase in F. pedrosoi sclerotic cells as well as the effect of peptidase inhibitors (PIs) on its enzymatic activity and viability. Our data showed that sclerotic cells are able to secrete pepstatin A-sensible aspartic peptidase when grown under chemically defined conditions. In addition, aspartic PIs (ritonavir, nelfinavir, indinavir, and saquinavir), which are clinically used in the HIV chemotherapy, significantly decreased the fungal peptidase activity, varying from 55 to 99%. Moreover, sclerotic cell-derived aspartic peptidase hydrolyzed human albumin, an important serum protein, as well as laminin, an extracellular matrix component, but not immunoglobulin G and fibronectin. It is well-known that aspartic peptidases play important physiological roles in fungal cells. With this task in mind, the effect of pepstatin A, a classical aspartic peptidase inhibitor, on the F. pedrosoi proliferation was evaluated. Pepstatin A inhibited the fungal viability in both cellular density- and drug-concentration manners. Moreover, HIV-PIs at 10 µM powerfully inhibited the viability (>65%) of F. pedrosoi sclerotic cells. The detection of aspartic peptidase produced by sclerotic cells, the parasitic form of F. pedrosoi, may contribute to reveal new virulence markers and potential targets for chromoblastomycosis therapy.
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BACKGROUND: Melanin production has been associated with virulence in various pathogenic fungi, including Fonsecaea pedrosoi, the major etiological agent for chromoblastomycosis, a subcutaneous fungal disease that occurs in South America. OBJECTIVE: The aim of this study was to evaluate the effects of acid-basic extracted F. pedrosoi melanin particles and fungal cell ghosts obtained by Novozym 234 treatment on their ability to activate the human complement system. METHODS: The ability of melanin particles and fungal cell ghosts to activate the human complement system was evaluated by complement consumption, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). FINDINGS: Unsensitised melanin particles and melanin ghosts presented complement consumption of 82.67 ± 2.08% and 96.04 ± 1.13%, respectively. Immunofluorescence assays revealed intense deposition of the C3 and C4 fragments on the surface of melanin particles and ghosts extracted from F. pedrosoi. Deposition of the C3, C4, and C5 fragments onto melanin samples and zymosan was confirmed by ELISA. Deposition of small amounts of C1q and C9 onto melanin samples and zymosan was detected by ELISA. CONCLUSION: Fonsecaea pedrosoi melanin particles and fungal cell ghosts activated the complement system mainly through an alternative pathway.
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Ascomicetos/química , Ativação do Complemento , Proteínas do Sistema Complemento/imunologia , Melaninas/farmacologia , Animais , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Humanos , Melaninas/biossíntese , Melaninas/isolamento & purificaçãoRESUMO
Monohexosylceramides (CMHs) are highly conserved fungal glycosphingolipids playing a role in several cellular processes such as growth, differentiation and morphological transition. In this study, we report the isolation, purification and chemical characterization of CMHs from Rhizopus stolonifer and R. microspores. Using positive ion mode ESI-MS, two major ion species were observed at m/z 750 and m/z 766, respectively. Both ion species consisted of a glucose/galactose residue attached to a ceramide moiety containing 9-methyl-4,8-sphingadienine with an amidic linkage to a hydroxylated C16:0 fatty acid. The antimicrobial activity of CMH was evaluated against Gram positive and Gram negative bacteria using the agar diffusion assay. CMH from both Rhizopus species inhibited the growth of Bacillus terrae, Micrococcus luteus (M. luteus) and Pseudomonas stutzeri (P. stutzeri) with a MIC50 of 6.25, 6.25 and 3.13 mg/mL, respectively. The bactericidal effect was detected only for M. luteus and P. stutzeri, with MBC values of 25 and 6.25 mg/mL, respectively. Furthermore, the action of CMH on the biofilm produced by methicillin-resistant Staphylococcus aureus (MRSA) was analyzed using 12.5 and 25 mg/mL of CMH from R. microsporus. Total biofilm biomass, biofilm matrix and viability of the cells that form the biofilm structure were evaluated. CMH from R. microsporus was able to inhibit the MRSA biofilm formation in all parameters tested.
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Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Cerebrosídeos/isolamento & purificação , Cerebrosídeos/farmacologia , Rhizopus/química , Antibacterianos/química , Biomassa , Brasil , Cerebrosídeos/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Ethanol extracts obtained from Schinus terebinthifolius Raddi fruits and leaves were active against Escherichia coli with MIC of 78 µg mL-1 for both extracts. Phytochemical analyses revealed a major presence of phenolic acids, tannins, fatty acids and acid triterpenes in the leaves and phenolic acids, fatty acids, acid triterpenes and biflavonoids in the fruits. Major compounds isolated from the plant, such as the acid triterpene schinol, the phenolic acid derivative ethyl gallate and the biflavonoids agathisflavone and tetrahydroamentoflavone, showed very little activity against E. coli. Bioautography of the ethanol extracts on silica gel plate showed inhibition zones for E. coli. They were removed from the plate and the compounds identified as a mixture of myristic, pentadecanoic, palmitic, heptadecanoic, stearic, nonadecanoic, eicosanoic, heneicosanoic and behenic fatty acids.
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Anacardiaceae/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antibacterianos/química , Biflavonoides/isolamento & purificação , Biflavonoides/farmacologia , Frutas/química , Ácido Gálico/análogos & derivados , Ácido Gálico/isolamento & purificação , Ácido Gálico/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologiaRESUMO
BACKGROUND Melanin production has been associated with virulence in various pathogenic fungi, including Fonsecaea pedrosoi, the major etiological agent for chromoblastomycosis, a subcutaneous fungal disease that occurs in South America. OBJECTIVE The aim of this study was to evaluate the effects of acid-basic extracted F. pedrosoi melanin particles and fungal cell ghosts obtained by Novozym 234 treatment on their ability to activate the human complement system. METHODS The ability of melanin particles and fungal cell ghosts to activate the human complement system was evaluated by complement consumption, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). FINDINGS Unsensitised melanin particles and melanin ghosts presented complement consumption of 82.67 ± 2.08% and 96.04 ± 1.13%, respectively. Immunofluorescence assays revealed intense deposition of the C3 and C4 fragments on the surface of melanin particles and ghosts extracted from F. pedrosoi. Deposition of the C3, C4, and C5 fragments onto melanin samples and zymosan was confirmed by ELISA. Deposition of small amounts of C1q and C9 onto melanin samples and zymosan was detected by ELISA. CONCLUSION Fonsecaea pedrosoi melanin particles and fungal cell ghosts activated the complement system mainly through an alternative pathway.