Repositório Institucional - Unifesp :: Navegando por Palavras-chave "Antimicrobial activity"

Navegando por Palavras-chave "Antimicrobial activity"

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Acesso aberto (Open Access)
Avaliação da atividade biológica de metabólitos de Lippia alba (Verbenaceae), Plectranthus amboinicus e Plectranthus barbatus (Lamiaceae)
(Universidade Federal de São Paulo, 2016-02-19) Santos, Nara Oshiro dos [UNIFESP]; Sartorelli, Patricia [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
This study aimed to identify substances with antimicrobial, antiparasitic and antitumor activities of extract and essential oil from the leaves of Lippia alba (Mill.) N.E. Brown and evaluate the antimicrobial and antitumor activities of essential oils from leaves of Plectranthus amboinicus (Lour.) Spreng and Plectranthus barbatus Andrews. The major compounds identified in the essential oil of L. alba leaves were monoterpenes nerol/geraniol (27%) and neral/geranial (22%), the ketone, 6-methyl-5- hepten-2-one (12%) and sesquiterpene, (E)-caryophyllene (9%). This oil showed cytotoxic activity in vitro against B16F10 (murine melanoma) with IC50 of 45.82 µg/mL. Furthermore, it was found that the oil has antimicrobial activity in vitro, inhibiting Gram-negative bacteria, except Pseudomonas aeruginosa, Gram-positive bacteria and yeasts. The dichloromethane phase obtained from the methanol extract of the leaves of this species showed activity against Leishmania (Leishmania) amazonensis with IC50 of 50.8 µg/mL and among the active groups of fractions were identified triterpenes mixture of oleanolic and ursolic acids, in addition to the steroid stigmasterol, all described in L. alba for the first time. The essential oil from leaves of P. amboinicus presented as major compounds carvacrol (38%), γ-terpinene (15%), (Z)-caryophyllene (14%) and p-cymene (12%), showing cytotoxic activity against B16F10 with IC50 similar to standard drug, however, twice more specific, in addition, showed antimicrobial activity against S. epidermidis, C. albicans, C. neoformans (serotype D), C. gattii (serotypes B and C) and S. cerevisiae. In turn, essential oil from leaves of P. barbatus presentes as major compounds (Z) -caryophyllene (18%), germacrene -D (17%), viridiflorene (14%), cyclosativene (10%) and α -pinene (9%), and has demonstrated activity against C. neoformans (serotype A) and C. gattii (serotype C).
Acesso aberto (Open Access)
Avaliação do efeito da massa molar na quaternização da quitosana e nas propriedades dos filmes de quitosana quaternizada
(Universidade Federal de São Paulo, 2023-07-31) Faria, Danielle Bitencourt [UNIFESP]; Moraes, Mariana Agostini de [UNIFESP]; Silva, Classius Ferreira da [UNIFESP]; http://lattes.cnpq.br/4514485329529047; http://lattes.cnpq.br/0644374691728856; https://lattes.cnpq.br/4567597606259744
A quitosana é um polissacarídeo biocompatível, biodegradável e biofuncional. Entretanto, a maioria das quitosanas comerciais e desenvolvidas em laboratórios de pesquisa são solúveis apenas em pHs ácidos, o que motivou o desenvolvimento de modificações químicas, tais como a quaternização, que tornam a quitosana solúvel em todas as faixas de pH e expandem seu campo de aplicação. O processo de quaternização mais comum é o de N-alquilação, a partir do qual obtém-se o composto Cloreto de N-(2-hidroxi)-propril-3-trimetilamônio quitosana (HTCC), que é amplamente utilizado em aplicações biológicas e farmacêuticas. Sabe-se que as propriedades da quitosana são influenciadas diretamente pela massa molar e grau de desacetilação. No entanto, a literatura carece de estudos que analisem a influência da massa molar da quitosana no processo de quaternização e nas propriedades dos filmes obtidos a partir da quitosana quaternizada, sendo este o objetivo do presente estudo. Os resultados obtidos indicaram que o aumento da massa molar da quitosana resulta no aumento do grau de quaternização, possivelmente devido à maior disponibilidade para reação dos grupos amino presentes na molécula de quitosana. Além disso, os filmes de quitosana quaternizada foram preparados por casting e analisados quanto às suas propriedades físico-químicas e biológicas. Os filmes de quitosana quaternizada apresentaram comportamento elastomérico, com deformação na ruptura variando de 73 a 102%, valor 74% maior, em média, do que os filmes de quitosana. Além disso, os filmes de quitosana quaternizada apresentaram excelente atividade antimicrobiana, com halos de inibição de S. aureus e E. coli variando de 30 a 36 mm. Desta forma, é possível concluir que a massa molar é um fator preponderante que deve ser considerado na análise de reações de quaternização da quitosana e que os filmes de quitosana quaternizada são uma excelente opção para aplicações que exijam grande elasticidade e controle do crescimento microbiano, abrangendo desde a área de embalagens e recobrimentos até a área médico-farmacêutica.
Embargo
Bionanomining of copper-based nanoparticles using pre-processed mine tailings as the precursor
(Elsevier, 2023-03-28) Brandão, Igor Yannick Vasconcellos; Macedo, Erenilda Ferreira de; Silva, Pedro Henrique Barboza de Souza; Batista, Aline Fontana; Petroni, Sérgio Luis Graciano; Gonçalves, Maraisa [UNIFESP]; Conceição, Katia [UNIFESP]; Trichês, Eliandra de Sousa [UNIFESP]; Tada, Dayane Batista [UNIFESP]; Maass, Danielle [UNIFESP]; http://lattes.cnpq.br/3431482044015696
The bacterial synthesis of copper nanoparticles emerges as an eco-friendly alternative to conventional techniques since it comprises a single-step and bottom-up approach, which leads to stable metal nanoparticles. In this paper, we studied the biosynthesis of Cu-based nanoparticles by Rhodococcus erythropolis ATCC4277 using a preprocessed mining tailing as a precursor. The influence of pulp density and stirring rate on particle size was evaluated using a factor-at-time experimental design. The experiments were carried out in a stirred tank bioreactor for 24 h at 25 ◦C, wherein 5% (v/v) of bacterial inoculum was employed. The O2 flow rate was maintained at 1.0 L min-1 and the pH at 7.0. Copper nanoparticles (CuNPs), with an average hydrodynamic diameter of 21 ± 1 nm, were synthesized using 25 g.L-1 of mining tailing and a stirring rate of 250 rpm. Aiming to visualize some possible biomedical applications of the as-synthesized CuNPs, their antibacterial activity was evaluated against Escherichia coli and their cytotoxicity was evaluated against Murine Embryonic Fibroblast (MEF) cells. The 7-day extract of CuNPs at 0.1 mg mL-1 resulted in 75% of MEF cell viability. In the direct method, the suspension of CuNPs at 0.1 mg mL-1 resulted in 70% of MEF cell viability. Moreover, the CuNPs at 0.1 mg mL-1 inhibited 60% of E. coli growth. Furthermore, the NPs were evaluated regarding their photocatalytic activity by monitoring the oxidation of methylene blue (MB) dye. The CuNPs synthesized showed rapid oxidation of MB dye, with the degradation of approximately 65% of dye content in 4 h. These results show that the biosynthesis of CuNPs by R. erythropolis using pre-processed mine tailing can be a suitable method to obtain CuNPs from environmental and economical perspectives, resulting in NPs useful for biomedical and photocatalytic applications.
Acesso aberto (Open Access)
Bioprospecção do potencial antimicrobiano, antiparasitário e antitumoral de metabólitos secundários produzidos por fungos do gênero Aspergillus Spp.
(Universidade Federal de São Paulo (UNIFESP), 2018-06-28) Calado, Juliana Cristina Pereira [UNIFESP]; Batista, Wagner Luiz [UNIFESP]; http://lattes.cnpq.br/4373797404389169; http://lattes.cnpq.br/4353724670961832; Universidade Federal de São Paulo (UNIFESP)
Filamentous fungi produce a wide variety of secondary metabolites that have a significant impact on society. Some metabolites are exploited by their activity as antibiotics and drugs; others are involved in diseases, in the interaction of fungi with plants and animals. In this context, the objective of this work was to obtain biologically active secondary metabolites produced by fungi isolated from the composting of the Fundação Zoológico de São Paulo (FPZSP). In this study, 71 organic extracts were used, 60 filamentous fungi and 11 yeasts. Of the 71 analyzed samples 25 presented antimicrobial activity in disc diffusion assays, and 23 samples showed activity against Staphylococcus aureus, 15 against Bacillus cereus and only one sample (I75) showed activity against Escherichia coli and Pseudomonas aeruginosa. The minimum inhibitory concentration (MIC) values were determined by microdilution in broth. Four of these samples had good antimicrobial activity (MIC 62.5 μg / mL) and 7 showed moderate activity (100500 μg / mL). Four samples showed antitumor activity with selectivity varying from 1.8 to 7.5 times. The best results were obtained for the activity against Leishmania (Leishmania) amazonensis. In the tests of leishmanicidal activity against the promastigote forms, 12 samples presented IC50 values equal to or less than 5 μg / mL, of which 3 showed good selectivity against the parasite in relation to the murine fibroblast lineage (values ranging from 5 to 50 times). Similar results for leishmanicidal activity against amastigote forms were observed in two of these extracts (I06 and I75). The I06 extract induced cell death by mitochondrial apoptosis and ROS production in the promastigote forms of L. (L.) amazonensis. The therapeutic potential of the organic extract of isolate I06 in cutaneous leishmaniasis model was also evaluated. BALB / c mice infected with L. (L.) amazonensis and treated with I06 extract showed a significant reduction in the lesion size in the paw as well as the parasite load. No signs of hepatic or renal toxicity were observed from histological analyzes and evaluation of serum levels of some biochemical markers. For the identification of the fungal species used in this study, partial sequencing of the intergenic region (STI) of ribosomal DNA and a region of the calmodulin gene was performed. All isolates with some biological activity belong to different strains of Aspergillus fumigatus. Thus, this dataset strongly suggests that a molecule or set of organic extract molecules from secondary metabolites of A. fumigatus (isolated I06) has leishmanicidal activity with high selectivity and low toxicity, thus presenting great potential for therapeutic use.
Acesso aberto (Open Access)
Chemical and biological characterization of four new linear cationic alpha-helical peptides from the venoms of two solitary eumenine wasps
(Elsevier B.V., 2011-06-01) Rangel, Marisa; Santos Cabrera, Marcia Perez dos; Kazuma, Kohei; Ando, Kenji; Wang, Xiaoyu; Kato, Manabu; Nihei, Ken-ichi; Hirata, Izaura Yoshico [UNIFESP]; Cross, Tyra J.; Garcia, Angelica Nunes; Faquim-Mauro, Eliana L.; Franzolin, Marcia Regina; Fuchino, Hiroyuki; Mori-Yasumoto, Kanami; Sekita, Setsuko; Kadowaki, Makoto; Satake, Motoyoshi; Konno, Katsuhiro; Toyama Univ; Butantan Inst; São Paulo State Univ; Yamada Apiculture Ctr Inc; Utsunomiya Univ; Universidade Federal de São Paulo (UNIFESP); Univ Victoria; Natl Inst Biomed Innovat; Tokushima Bunri Univ
Four novel peptides were isolated from the venoms of the solitary eumenine wasps Eumenes rubrofemoratus and Eumenes fraterculus. Their sequences were determined by MALDI-TOF/TOF (matrix assisted laser desorption/ionization time-of-flight mass spectrometry) analysis, Edman degradation and solid-phase synthesis. Two of them, eumenitin-R (LNLKGLIKKVASLLN) and eumenitin-F (LNLKGLFKKVASLLT), are highly homologous to eumenitin, an antimicrobial peptide from a solitary eumenine wasp, whereas the other two, EMP-ER (FDIMGLIKKVAGAL-NH(2)) and EMP-EF (FDVMGIIKKIAGAL-NH(2)), are similar to eumenine mastoparan-AF (EMP-AF), a mast cell degranulating peptide from a solitary eumenine wasp. These sequences have the characteristic features of linear cationic cytolytic peptides; rich in hydrophobic and basic amino acids with no disulfide bond, and accordingly, they can be predicted to adopt an amphipathic alpha-helix secondary structure. in fact, the CD (circular dichroism) spectra of these peptides showed significant alpha-helical conformation content in the presence of TFE (trifluoroethanol), SDS (sodium dodecylsulfate) and asolectin vesicles. in the biological evaluation, all the peptides exhibited a significant broad-spectrum antimicrobial activity, and moderate mast cell degranulation and leishmanicidal activities, but showed virtually no hemolytic activity. (C) 2011 Elsevier B.V. All rights reserved.
Somente Metadadados
Chemical Composition and Antimicrobial Activity of Essential Oils from Chromolaena laevigata during Flowering and Fruiting Stages
(Wiley-Blackwell, 2013-04-01) Murakami, Cynthia; Lago, Joao H. G. [UNIFESP]; Perazzo, Fabio F. [UNIFESP]; Ferreira, Karen S. [UNIFESP]; Lima, Marcos E. L.; Moreno, Paulo R. H.; Young, Maria C. M.; Inst Bot; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
The chemical compositions and antimicrobial activities of essential oils from the leaves, stems, capitula, and cypselas of Chromolaena laevigata were evaluated at two different phenological stages, flowering and fruiting. Thirty-eight compounds were identified in the crude oils by GC/MS. the sesquiterpene laevigatin was the major constituent of the leaf, capitulum, and cypsela oils, while the sesquiterpene spathulenol was the main component in the stem oils. the antimicrobial activities of the oils were evaluated against Candida albicans, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Stem oil obtained from Chromolaena laevigata during the fruiting stage generally showed the highest activity with minimum inhibitory concentration (MIC) values of 62.5g/ml against Candida albicans and S. aureus, and 500g/ml against P. aeruginosa and E. coli. Pure laevigatin exhibited MIC values of 500 and 125g/ml against C. albicans and S. aureus, respectively, indicating that this constituent could be responsible, at least in part, for the antimicrobial activities detected in the crude oils. More studies concerning the biological activities of isolated derivatives are required to improve our knowledge of the antimicrobial potential of volatile compounds present in native plants.
Somente Metadadados
Chemical composition and biological activities of Guatteria elliptica R. E. Fries (Annonaceae) essential oils
(Taylor & Francis Inc, 2018) Rajca Ferreira, Agnieszka Katarzyna; Lourenco, Felipe Rebello; Marx Young, Maria Claudia; Leite Lima, Marcos Enoque; Cordeiro, Ines; Suffredini, Ivana Barbosa; Lopes, Patricia Santos [UNIFESP]; Hrihorowitsch Moreno, Paulo Roberto
Leaf from two Guatteria elliptica R. E. Fries (Annonaceae) specimens were collected at Paranapiacaba and Caraguatatuba in Sao Paulo (Brazil). The essential oils presented (GC/GC-MS), as major compound, spathulenol (53.9%) for the Paranapiacaba specimen and caryophyllene oxide (40.9%) for Caraguatatuba. The oils showed low antioxidant activity with EC50 = 7.24 +/- 1.03 and 28.68 +/- 5.78 mg/mL, respectively, for Paranapiacaba and Caraguatatuba specimens. Both oils did not show a relevant (MIC > 3 mg/mL) antimicrobial activity. However, the Paranapiacaba oil presented an important antitumour activity against breast and prostate cancer cells (IC50 = 7.01 +/- 0.23 and 5.35 +/- 0.35 mu g/mL, respectively) and a low cytotoxicity against normal fibroblast cells (IC50 > 22.27 e IC10 = 18.55 +/- 1.89 mu g/mL). Isolated major compound, spathulenol, showed good activity against MCF-7 and PC-3 with IC50 = 5.38 +/- 0.20 and 2.25 +/- 0.28 mu g/mL mu g/mL, respectively.
Somente Metadadados
Chitosan active films containing agro-industrial residue extracts for shelf life extension of chicken restructured product
(Elsevier Science Bv, 2018) Serrano-Leon, Juan S.; Bergamaschi, Keityane B.; Yoshida, Cristiana M. P. [UNIFESP]; Saldana, Erick; Selani, Miriam M.; Rios-Mera, Juan D.; Alencar, Severino M.; Contreras-Castillo, Carmen J.
This study aimed to develop chitosan films incorporating natural antioxidants from peanut skin (EPS) and pink pepper residue (EPP) extracts, as well as to evaluate their effects on lipid oxidation, pH, color, and microbial counts of a restructured chicken product. EPS had higher phenolic content and antioxidant activity compared to EPP. When both extracts were applied to chicken meat and the chitosan films, there were no differences for color, pH and total mesophilic counts compared to control at the end of the storage period. For lipid oxidation (peroxide value and thiobarbituric acid reactive substances), both extracts proved to be as effective as butylated hydroxytoluene to maintain the oxidative stability of the chicken product. The microbial counts of psychrotrophic microorganisms were significantly lower for treatments with active films. Chitosan active films with residue extracts may maintain the quality of chicken products due to their antioxidant and antimicrobial potential.
Acesso aberto (Open Access)
Comparação das atividades antimicrobianas de meropenem e imipenem/cilastatina: o laboratório necessita testar rotineiramente os dois antimicrobianos?
(Sociedade Brasileira de Patologia ClínicaSociedade Brasileira de PatologiaSociedade Brasileira de Citopatologia, 2002-01-01) Gales, Ana Cristina [UNIFESP]; Mendes, Rodrigo Elisandro [UNIFESP]; Rodrigues, José [UNIFESP]; Sader, Helio Silva [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Meropenem and imipenem are the most active and potent ß-lactams against gram-negative bacteria and the only carbapenems commercially available in Brazil, USA, and Europe. Meropenem has higher in vitro activity against gram-negative bacteria, while imipenem has slightly higher in vitro activity against gram-positive. The objectives of this study are to compare the in vitro activities of these carbapenems and to evaluate the necessity of susceptibility testing both compounds at the routine of the microbiology laboratory. The broth microdilution results of 2,144 gram-negative bacilli were analyzed. Against Enterobacteriaceae meropenem was at least eight-fold more potent than imipenem. Against Pseudomonas aeruginosa meropenem (MIC50, 1mug/ml) was also more potent than imipenem (MIC50, 2mug/ml), and against Acinetobacter baumannii both carbapenems presented similar in vitro activities (MIC50, 1mug/ml for both). Only 2.7% of the isolates presented discrepant category results between the carbapenems; i.e. susceptible to one and resistant to the other. Forty-six isolates (2.14%) were susceptible to meropenem and resistant to imipenem; while only 12 isolates (0.55%) were susceptible to imipenem and resistant to meropenem. The vast majority of discordant results (91.4%) occur among non-fermentative bacilli (NF-BGN). Five discordant results were detected among 1,350 Enterobacteriaceae evaluated (0.37%); while 53 discrepant results were detected among 794 NF-BGN (6.64%). Isolates showing susceptibility to meropenem and resistance to imipenem account for 80% of the discrepant results. The results of this study indicate that the microbiology laboratory may susceptibility test only one of the carbapenems for Enterobacteriaceae and use the same category result for the other one. It is important that the results for both carbapenems are sent to the physicians in order for them to be able to choose the most appropriated for the case. On the other hand, for NF-BGN the laboratory should susceptibility test both carbapenems.
Acesso aberto (Open Access)
Duguetia lanceolata St. -Hil (Annonaceae): composição química da fração alcaloídica e do óssencial e avaliação da atividade anti-Trypanosoma cruzi e antimicrobiana
(Universidade Federal de São Paulo, 2018-04-03) Dantas, Erick Pereira [UNIFESP]; Sartorelli, Patricia [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
The Annonaceae family is composed by 135 genus and 2500 species; 34 of these can be found in South America. Among these, 29 take place in Brazil, including the Duguetia genus with 50 of the 80 classified species. The specie selected for this study was Duguetia lanceolata, known popularly as "pindaiva" or "ateira-da-mata", occurs in the Brazil, in the Dense Ombrophilous Forest, Seasonal Semideciduos Forest, Riparian Forest, Padulosa Forest and Cerrado. The present work aims to evaluate the antiparasitic (Trypanossoma cruzi) and antifungal potential (Candida albicans, Cryptococcus neoformans and Saccharomyces cerevisiae) of alkaloids and other fixed and volatile metabolites isolated from the leaves of D. lanceolata. The crude extract was subjected to acid-base extraction yielding the alkaloid extract (EA). EA was subjected to column chromatography using flash silica yielding fifteen fractions. Fractions EA9 and EA10 were selected after confirmation of alkaloids in these fractions by Dragendorff. EA9 and EA10 were subjected to other chromatographic procedures as flash silica chromatography, Sephadex LH-20, HPLC and HPLC-MS. After these steps, it was possible to isolate 2 fixed compounds, glaucine (aporphic alkaloid) and litholide (lactone) and to separate and identify other 13 fixed compounds, 3 aporphinal alkaloids (glaucine, 7-hydroxydehydroglaucine, dehydroglacaine, norglaucine and boldine), 3 oxoaporfine alkaloids (liriodenine, oxoglaucine and lanuginosine), 2 pyrrolizidine alkaloids (ipanguline B2 and isoipanguline B2), 2 sesquiterpenes (capsidiol and β-caryophyllene), and 2 aromatic compounds (1,3,5-trimethoxybezene and one unknown). All these compounds were characterized and identified by uni- and bidimensional spectroscopic techniques, mass spectrometry and compared to the literature. Glaucine and loliolide were evaluated for antiparasitic potential and cytotoxicity. For the trypomastigotes the two substances presented similar activity > 150.0 μM. For the amastigotes the lololide presented activity of > 30.0 μM that is greater than that of the glaucina of 80.7 μM. As for cytotoxicity, the two were not considered cytotoxic due to values > 200.0 μM. The essential oil of the leaves of Duguetia lanceolata was analyzed for its chemical composition by CG-FID and CG-MS, as result 13 compounds were identified corresponding to 83.73% of the total oil composition with bisabolene (24.87%), germacrene-D (18 , 60%) and gurjuren α (12.08%) as major compounds. For the isolation of the major compounds, the essential oil was subjected to chromatographic procedure by silica normal phase column soaked with AgNO3, obtaining 12 fractions. The DLO 3 fraction was subjected to preparative thin layer chromatography, affording 5 subfractions. After analysis of the NMR ¹H and ¹³C spectrums of the fraction DLO3-4 and DLO-5. They are shown to be constituted by the epoxy-caryophyllene and β-bisabolene, respectively. The potential antimicrobial activity of the essential oil, fractions and subfractions were evaluated against Candida albicans, Cryptococcus neoformans and Saccharomyces cerevisiae strains. Crude oil showed antimycotic activity against Cryptococcus neoformans and Saccharomyces cerevisiae. The DLO 3 fraction demonstrated antifungal activity against Candida albicans and Cryptococcus neoformans. Although the subfractions DLO3-4 (ephoxi-caryophyllene) and DLO3-5 (β-bisabolene) have not demonstrated antimicrobial activity, in combination these subfractions showed antifungal activity against Candida albicans and Cryptococcus neoformans, thus suggesting potential synergism between the compounds. Keywords: Duguetia lanceolata, alkaloids, anti-Trypanosoma activity, antimicrobial activity, essential oil. Keyword: Duguetia lanceolata, alkaloids, anti-Trypanosoma activity, antimicrobial activity, essential oil.
Acesso aberto (Open Access)
Estudo químico e avaliação da atividade antimicrobiana dos óleos essenciais extraidos das especies Pimenta dioica (Myrtaceae) e Chenopodium ambrosioides (Amaranthaceae)
(Universidade Federal de São Paulo, 2016-04-15) Phanord, Clerlune [UNIFESP]; Sartorelli, Patricia [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Currently infectious diseases remain one of the most serious public health problems and have caused many deaths. According to OMS, infectious diseases caused 14.7 million deaths in 2001, or 26% of total world mortality. Since the discovery of penicillin by Alexander Fleming in 1928, many antibiotics are available in pharmacies, but despite the existence of these antibiotics, infectious diseases, instead of being completely eradicated are reappearing and also new infectious diseases have emerged. The causes of this problem are diverse: there are few specific antibiotics available, the treatment is very expensive, and the most disturbing: the microorganisms are increasingly resistant to antibiotics. Therefore, as a contribution to the discovery of new antibiotics, this study aimed to find new substances that might be prototypes of antimicrobial drugs, or at least an effective and low cost to fight these pathogens. Thus, the chemical study was proposed of the essential oils of the species Pimenta dioica (Myrtaceae) and Chenopodium ambrosioides (Amaranthaceae), and the evaluation of antimicrobial activity against various strains of bacteria and yeast. The majority of essential oil compounds of P. dioica were phenylpropanoids eugenol and chavicol beyond monoterpene myrcene, whereas for C. ambrosioides were monoterpenes: ascaridol and terpinene. Regarding the antimicrobial activity, the tested strains showed sensitivity to the essential oil of P. dioica and the isolated compound eugenol, except for Pseudomonas aeruginosa. The MIC90 for both ranged from 0.25 mg/mL for E. faecalis and 1 mg/mL for all tested bacteria. The same concentration was valid for the of essential oil of P. dioica and eugenol. Only for tested Cryptococcus sp. showed sensitivity of 0.5 mg/mL to MIC90. With respect to C. ambrosioides essential oil and the main component ascaridol, the two were active only for E. coli with MIC90 of 2 mg/mL. Regarding the tested fungal strains, C. ambrosioides essential oil and monoterpene ascaridol were active for all strains tested. The MIC90 for crude oil C. ambrosioides was 0.25 mg/mL for all tested candidas, and in C. albicans theresult was positive at 0.50 mg/mL, and tested for Cryptococcus. The ascaridol showed MIC90 of 0.25 mg/mL for all the lines candidas except in C. Krusi which was 0.5 mg/mL, and in the case of Cryptococcus the MIC90 was 1 mg/mL.
Acesso aberto (Open Access)
Estudo químico e biotecnológico de fungos endofíticos associados a Calea pinnatifida (Asteraceae) buscando compostos bioativos e de ação antimicrobiana
(Universidade Federal de São Paulo, 2024-10-11) Fernandes, Bianca Barna [UNIFESP]; Sartorelli, Patricia [UNIFESP]; Vasconcellos, Suzan Pantaroto de [UNIFESP]; http://lattes.cnpq.br/4254240006926714; http://lattes.cnpq.br/6836392358779448; http://lattes.cnpq.br/4986576887385145
Os fungos endofíticos são microrganismos que vivem internamente nas plantas, geralmente sem causar danos ao hospedeiro, estabelecendo relações simbióticas que podem resultar na produção de compostos bioativos com ampla aplicabilidade. Este estudo focou na análise de fungos endofíticos isolados de Calea pinnatifida, uma planta medicinal conhecida por suas propriedades terapêuticas, visando avaliar o potencial antimicrobiano dos metabólitos produzidos por esses microrganismos e explorar seu arsenal enzimático na biotransformação de compostos. Foram isolados 23 fungos endofíticos a partir de caules e folhas de C. pinnatifida, os quais foram cultivados e identificados como pertencentes aos gêneros Colletotrichum, Hypomontagnella, Neopestalotiopsis, Nigrospora e Annulohypoxylon. Partes aéreas da planta, além dos fungos isolados, foram submetidos a extração de seus metabólitos, e o perfil químico resultante foi analisado por técnicas cromatográficas e espectroscópicas, associadas a ferramentas de desreplicação e caracterização de compostos. As análises revelaram uma grande diversidade química no metabolismo dos fungos endofíticos, com destaque para derivados de ácido tetrônico, como o Nudulisporácido A e, pela primeira vez descrito, o Nodulisfuranol isolados de Hypomontagnella barbarensis. A desreplicação dos extratos da planta indicou a presença de lactonas sesquiterpênicas e ácidos fenólicos, compostos descritos previamente na literatura. Adicionalmente, os extratos dos fungos endofíticos foram testados quanto à atividade antimicrobiana, utilizando métodos de difusão em disco e determinação da concentração inibitória mínima, destacando-se os extratos de Colletotrichum karstii e Hypomontagnella barbarensis, que apresentaram resultados promissores de inibição contra S. aureus, S. cerevisiae e C. albicans. Os fungos também foram induzidos a biotransformar limoneno, apenas 3 deles (Colletotrichum karstii e Neopestalotiopsis clavispora) demonstraram seu potencial enzimático no processamento desse substrato, transformando o limoneno em produtos como o limoneno-1,2-epóxido e posteriormente limoneno-1,2-diol, seguindo a mesma rota de conversão descrita em literatura, realizada pela bactéria Rhodococcus erythropolis. Assim, o estudo reforça a importância de explorar fungos endofíticos como fontes valiosas de novos compostos bioativos, com potencial para aplicações clínicas.
Acesso aberto (Open Access)
Estudos de síntese, conformação e atividade biológica de análogos do peptídeo antimicrobiano longipina
(Universidade Federal de São Paulo (UNIFESP), 2017-03-31) Silva, Jones Montenegro da [UNIFESP]; Miranda, Antonio de [UNIFESP]; Silva Júnior, Pedro Ismael da; http://lattes.cnpq.br/7158586957386749; http://lattes.cnpq.br/1357848049935882; http://lattes.cnpq.br/4701582072086750; Universidade Federal de São Paulo (UNIFESP)
Longipina (Lp) é um potente peptídeo antimicrobiano isolado e caracterizado a partir da hemolinfa do Acustisoma longipe. É rico em lisina (K) e tirosina (Y) e sua sequência primaria é: SGYLPGKYVYKYKGKVF. O objetivo principal deste trabalho é estudar a relação estrutura-atividade de novos análogos da Lp, assim como entender os seus mecanismos de ação. Os peptídeos foram sintetizados pelo método de fase sólida manual e foram purificados e caracterizados por cromatografia líquida de fase reversa e por espectrometria de massas. As atividades antimicrobianas dos peptídeos foram avaliadas através de um ensaio de inibição de crescimento líquido contra P. aeruginosa, E. coli, S. marcescens, E. c1oacae, C. albicans, C. parapsilosis, C. tropicalis, C. neoformans, A. niger, C. herbarum e P. farinosus. As atividades hemolíticas e de resistência à degradação foram feitas, respectivamente, com hemácias e plasma humanos. Após uma análise dos resultados, observamos que os análogos: Ac_[Arg7,12,14,16]_Lp_NH2A,c_[Trp3,9,11,13]_Lp_NH2A;c_[Trp3,9,11,13A, rg7,12,14,16]_ Lp-NH2, Ac-[Des-Ser1, Trp3,9,11,13,Arg7,12,14,16]_Lp_NH2foram os mais ativos quando comparados com a Lp. Até a concentração de 100 IJM todos os compostos testados não apresentaram atividade hemolítica. Os análogos mais ativos foram também os mais resistentes à degradação em plasma. Concluímos que a acetilação e amidação e a substituição dos resíduos de Lys por Arg e de Tyr por Trp geraram análogos mais potentes e menos líticos. As perspectivas futuras são a realização dos estudos conformacionais por dicroísmo circular e a avaliação das atividades antitumorais dos compostos estudados.
Acesso aberto (Open Access)
Nanoligas bimetálicas Ag/Cu: avaliação estrutural, morfológica e atividade antimicrobiana
(Universidade Federal de São Paulo, 2023-05-24) Harada, Bruna Naemi [UNIFESP]; Pellosi, Diogo Silva [UNIFESP]; http://lattes.cnpq.br/4319283598735971
O desenvolvimento de cepas microbianas multirresistentes a antibióticos tem gerado preocupações globais na área da saúde. Neste contexto, nanopartículas metálicas como as nanopartículas de prata (AgNP) e cobre (CuNP) vêm sendo avaliadas como alternativa aos antibióticos comerciais. Ambos os metais possuem atividade antimicrobiana, mas enquanto as CuNP apresentam baixo custo, mas baixa estabilidade, as AgNP apresentam ótima estabilidade, porém custo mais elevado. Assim, neste trabalho o foco foi a produção de nanoligas do tipo Ag/Cu em busca de propriedades sinérgicas entre os metais. O sucesso da síntese das NPs e nanoligas via redução química em solução aquosa contendo polivinilpirrolidona (PVP) dependeu da metodologia aplicada. Por exemplo, o ácido ascórbico (redutor fraco) não foi eficiente, já o boroidreto de sódio (redutor forte) produziu os nanomateriais, mas as partículas com cobre tiveram baixa estabilidade. Por fim, optou-se pela síntese de NPs do tipo core@shell (Ag/Cu@Ag), otimizando o processo de produção via a ferramenta estatística de planejamento fatorial. A camada externa (shell) de prata assegurou a estabilidade das nanoligas produzidas, sendo estas então caracterizadas por espectrofotometria no UV-Vis, por espalhamento dinâmico de luz a fim de obter as medidas de tamanho e potencial zeta, e por microscopia eletrônica de transmissão, confirmando a formação de partículas esféricas nanométricas bem como sua morfologia core@shell. As nanoligas Ag/Cu@AgNPs apresentaram forte atividade biocida contra bactérias Gram-positvas e Gram-negativas, mas não apresentaram atividade antifúngica. Assim, o trabalho mostra que nanoligas do tipo Ag/Cu@AgNPs são materiais promissores no tratamento de infecções bacterianas.
Somente Metadadados
A new mistletoe Phthirusa pyrifolia leaf lectin with antimicrobial properties
(Elsevier B.V., 2010-04-01) Costa, Romero M. P. B.; Vaz, Antonio F. M.; Oliva, Maria L. V. [UNIFESP]; Coelho, Luana C. B. B.; Correia, Maria T. S.; Carneiro-da-Cunha, Maria G.; Universidade Federal de Pernambuco (UFPE); Universidade Federal de São Paulo (UNIFESP)
Phthirusa pyrifolia leaf lectin (PpyLL) was obtained from the hemi-parasitic medicinal plant mistletoe through saline saturation and two consecutive chromatographic steps on Sephadex G-100 and ion exchange on CM-cellulose. SDS-PAGE of the protein under non-reducing conditions revealed a monomeric protein with a molecular weight of 15.6 kDa. Under reducing conditions in the presence of 2-mercaptoethanol, the protein showed two bands with molecular weights of 15 and 7 kDa. PpyLL, an acidic glycoprotein with 19% sugar content, was not dependent on divalent cations. It was stable up to 70 degrees C and exhibited maximum hemagglutination at pH 7.5. Lectin fluorescence emission spectra at different temperatures showed that the lectin fluorescence increased when the temperature increased. PpyLL showed a unique affinity for the phosphate derivative of fructose, fructose-1-6-biphosphate. PpyLL showed effective antimicrobial activities against bacteria (Gram-positive: Staphylococcus epidermidis. Streptococcus faecalis and Bacillus subtilis; Gram-negative: Klebsiella pneumoniae) and fungi (Fusarium lateritium and Rhizoctonia solani). Therefore, PpyLL specificity, as determined by a new sugar affinity, may be significant to determine its biological potential. (C) 2009 Elsevier B.V. All rights reserved.
Acesso aberto (Open Access)
Síntese, estudos conformacionais e atividade biológica de novos análogos do peptídeo antimicrobiano gomesina
(Universidade Federal de São Paulo (UNIFESP), 2016-08-31) Mendes, Roberta Brandao [UNIFESP]; Miranda, Antonio de [UNIFESP]; http://lattes.cnpq.br/1357848049935882; http://lattes.cnpq.br/9759007573287366; Universidade Federal de São Paulo (UNIFESP)
Gomesin (ZCRRLCYKQRCVTYCRGR-NH2) is an antimicrobial peptide isolated from hemocytes of the Brazilian spider Acanfhoscurria gomesiana. The molecule has four cysteines that form two intramolecular disulfide bridges at positions 2.15 and 6.11. Gm has a broad spectrum of action and a high toxicity against human erythrocytes. This study aimed to the synthesis of new analogues of gomesin to evaluate their structure-activity and their mechanisms of action in comparison to Gm. Thus, linear and cyclic analogs were synthesized, Ac-Gm2-15, Ac-[D-Lys8]-Gm2-15, Ac-Ifrp", D-Lys8]-Gm2-15, Ac- [Thr2,6,11,15]-Gm2_1A5c, -[ Thr2,6,11,15,D-Lys8]-Gm2_1a5nd Ac-[Thr2,6,11,15,D-Pro9]-Gm2_1b5y using the solid phase peptides synthesis in a t-Boc strategy. Then peptides were cleaved, purified and characterized. Antimicrobial activity were evaluated against C. albicans, B. megaferium, P. aeruginosa, P. expansum, C. neoformans, A. niger, Cladosporium sp and S. cerevisiae; hemolytic activity was determined against human erythrocytes; Peptides degradation resistance in human plasma and antitumoral activity against K562 cells were also evaluated. Structural analysis by Circular Dichroism spectroscopy and peptide/vesicle interaction using giant unilamellar vesicles and optical microscopy were also performed. Thermodynamical studies of the interaction peptide I lipid using large unilamellar vesicles (LUVs) was done by isothermal titration calorimetry (ITC). Our results showed that analogues, Ac-Gm2-15, Ac-[D-Lys8]-Gm2-15 and Ac-IIrp", D-Lys8]-Gm2-15, presented the best antimicrobial activity, particularly against microorganisms A. nigerand S. cerevisiae, their performance were even better than Gm. Ali showed low hemolytic activity even at 100 IJM concentration. They were quite resistant to degradation. Fro the Circular Dichroism studies, we observed that the cyclic compounds showed conformations similar than to gomesin, they also assume a p-hairpin conformation. On the other hand, linear analogues showed a prevalence of random conformation. The Iytic mechanism of action of Gm and Ac-Gm2-15 showed to be very similar, both of them caused a disruption of the membrane. Ac-[Thr2,6,11,15]-Gm2_1p5resented a pore formation mechanism. From our results, we had confirmed the crucial importance of the disulfide bridges in the Iytic mechanism of action; in fact its removal causes a decrease in the antimicrobial, hemolytic and antitumor activities. The disulfide bridges also have a great contribution to the stability and strength the action against plasma protease. Gomesin fragments should have less potency, maybe due to the lower amount of charge and also because of the removal of amino acids in the N- and C-terminal portions
Acesso aberto (Open Access)
Unraveling the antifungal activity of a South American rattlesnake toxin crotamine
(Elsevier B.V., 2013-02-01) Yamane, Érica Sayuri [UNIFESP]; Bizerra, Fernando César [UNIFESP]; Oliveira, Eduardo B.; Moreira, Jéssica Tanaka [UNIFESP]; Rajabi, Mohsen; Nunes, Gabriel Luiz Cocco [UNIFESP]; Souza, Ana O. de; Silva, Ismael Dale Cotrim Guerreiro da [UNIFESP]; Yamane, Tetsuo; Karpel, Richard L.; Silva, Pedro I.; Hayashi, Mirian Akemi Furuie [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Univ Maryland; Inst Butantan; CBA; Univ Maryland Baltimore Cty
Crotamine is a highly basic peptide from the venom of Crotalus durissus terrificus rattlesnake. Its common gene ancestry and structural similarity with the beta-defensins, mainly due to an identical disulfide bond pattern, stimulated us to assess the antimicrobial properties of native, recombinant, and chemically synthesized crotamine. Antimicrobial activities against standard strains and clinical isolates were analyzed by the colorimetric microdilution method showing a weak antibacterial activity against both Gram-positive and Gram-negative bacteria [MIC (Minimum Inhibitory Concentration) of 50->200 mu g/mL], with the exception of Micrococcus luteus [MIC ranging from 1 to 2 mu g/mL]. No detectable activity was observed for the filamentous fungus Aspergillus fumigatus and Trichophyton rubrum at concentrations up to 125 mu g/mL. However, a pronounced antifungal activity against Candida spp., Trichosporon spp., and Cryptococcus neoformans [12.5-50.0 mu g/mL] was observed. Chemically produced synthetic crotamine in general displayed MIC values similar to those observed for native crotamine, whereas recombinant crotamine was overridingly more potent in most assays. On the other hand, derived short linear peptides were not very effective apart from a few exceptions. Pronounced ultrastructure alteration in Candida albicans elicited by crotamine was observed by electron microscopy analyses. the peculiar specificity for highly proliferating cells was confirmed here showing potential low cytotoxic effect of crotamine against nontumoral mammal cell lines (HEK293, PC12, and primary culture astrocyte cells) compared to tumoral B16F10 cells, and no hemolytic activity was observed. Taken together these results suggest that, at low concentration, crotamine is a potentially valuable anti-yeast or candicidal agent, with low harmful effects on normal mammal cells, justifying further studies on its mechanisms of action aiming medical and industrial applications. (C) 2012 Elsevier Masson SAS. All rights reserved.

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