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1.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 309-322, mayo 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1396871

RESUMO

This paper describes the evaluation of the antimicrobial and hemolytic activity of the hexane, dichloromethane, ethyl acetate and methanol extracts from seeds and epicarps of Garcinia madruno; as well garcinol, morelloflavone and volkensiflavone isolated from the same species. In the preliminary test of bacterial susceptibility, hexane extracts from seeds and epicarps and the three compounds tested only displayed inhibitory growth effect against Gram-positive bacteria. The minimum inhibitory concentrations of extract and compounds ranging from 86.6 to 1253.4 µg/mL. The hemolytic activity was assessed; however, except for the methanol extract from seeds, none of the samples studied induced hemolysis. Thus, our results suggest that extracts and compounds from G. madruno have the potential to be used in the control of pathologies associated to Gram-positive bacteria. This is the first report of the antimicrobial and hemolytic activity of extracts of different polarity obtained from seeds and epicarps of this edible species.


El presente artículo describe la evaluación de la actividad antimicrobiana y hemolítica de los extractos de hexano, diclorometano, acetato de etilo y metanol, obtenidos de la semilla y el epicarpio de Garcinia madruno; así como de garcinol, morelloflavona y volkensiflavona; aislados de la misma especie. En el ensayo de susceptibilidad bacteriana, tanto el extracto de hexano obtenido a partir de la semilla y el epicarpio, y los tres compuestos aislados, únicamente mostraron actividad inhibitoria del crecimiento contra bacterias Gram-positivas. La concentración mínima inhibitoria presentó valores entre 86.6 y 1253.4 µg/mL. También se estableció la actividad hemolítica; sin embargo, con excepción del extracto metanólico obtenido a partir de las semillas, ninguna de las muestras evaluadas indujo hemólisis. Por lo tanto, los resultados sugieren que los extractos y compuestos de G. madruno tienen el potencial de ser usados en el control de bacterias Gram-positivas asociadas a diversas patologías. Este es el primer reporte de actividad antimicrobiana y hemolítica de extractos de diferente polaridad obtenidos de las semillas y epicarpios de esta especie comestible.


Assuntos
Extratos Vegetais/farmacologia , Garcinia/química , Hemolíticos/farmacologia , Antibacterianos/farmacologia , Sementes/química , Terpenos/análise , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Biflavonoides/análise
2.
Rev. Ciênc. Méd. Biol. (Impr.) ; 21(1): 53-59, maio 05,2022. fig, tab
Artigo em Português | LILACS | ID: biblio-1370669

RESUMO

Introdução: as terapias alternativas que utilizam plantas medicinais e fitoterápicos são bastante comuns no Brasil. Dentre várias espécies vegetais brasileiras utilizadas em terapias destacam-se as espécies da família Malvaceae. Objetivos: o presente estudo teve como objetivo avaliar a citotoxicidade in vitro e a genotoxicidade ex-vivo em compostos da Pavonia glazioviana Gürke espécie brasileira pertencente à família Malvaceae. Metodologia: métodos in vitro foram utilizados para verificar o potencial citotóxico por meio de ensaios hemolíticos e anti-hemolíticos e da análise genotóxica ex-vivo. O Extrato Etanólico Bruto (EEB) e Fração Clorofórmico (FC) foram obtidos na amostra vegetal utilizada neste estudo. Resultados: os produtos EEB-Pg e FC-Pg apresentaram baixo efeito citotóxico apenas nas concentrações de 50 e 100 µg / mL. As amostras expostas às concentrações de 500 e 1000 µg / mL apresentaram índice hemolítico alto a moderado com lise superior a 60%. Foi descrito efeito anti-hemolítico moderado em todas as amostras tratadas com 500 e 1000 µg / mL, com hemólise < 60%. Além disso, os compostos mostraram baixo efeito genotóxico ex-vivo, com um índice geral de células normais superior a 84% em todas as concentrações. Conclusões: os resultados sugerem um baixo perfil tóxico dos compostos obtidos da espécie Pavonia glazioviana, indicando limites seguros para o uso desses produtos naturais.


Introduction: alternative therapies using medicinal plants and herbal medicines are quite common in Brazil. Among several Brazilian plant species used in therapies, the species of the Malvaceae family stand out. Objetctives: the present study aimed to evaluate the in vitro cytotoxicity and ex-vivo genotoxicity in compounds of the Brazilian Pavonia glazioviana Gürke belonging to the Malvaceae family. Methodology: in vitro methods were used to verify the cytotoxic potential through hemolytic and antihemolytic assays and the ex-vivo genotoxic analysis. The Crude Etanolic Extract (CEE) and Cloroformic Fraction (CF) was obtained in vegetal sample used on this study. Results: the CEE-Pg and CF-Pg products only showed a low cytotoxic effect at the concentrations of 50 and 100 µg/mL. The exposure to the concentrations of 500 and 1000 µg/mL showed a high to moderate hemolytic index with lysis higher than 60%. A moderate anti-hemolytic effect was described in all samples treated with 500 and 1000 µg/mL, with hemolysis <60%. In addition, the compounds showed low ex-vivo genotoxic effect with a general index of normal cells greater than 84% at all concentrations. Conclusion: the results suggest a low toxic profile of the compounds obtained from the Pavonia glazioviana Gürke species belonging to the Malvaceae family, indicating safe limits for the use of these natural products.


Assuntos
Humanos , Extratos Vegetais/farmacologia , Malvaceae/química , Genotoxicidade , Hemolíticos/farmacologia , Plantas Medicinais/química , Relação Dose-Resposta a Droga
3.
Molecules ; 27(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35056852

RESUMO

Saponins are plant and marine animal specific metabolites that are commonly considered as molecular vectors for chemical defenses against unicellular and pluricellular organisms. Their toxicity is attributed to their membranolytic properties. Modifying the molecular structures of saponins by quantitative and selective chemical reactions is increasingly considered to tune the biological properties of these molecules (i) to prepare congeners with specific activities for biomedical applications and (ii) to afford experimental data related to their structure-activity relationship. In the present study, we focused on the sulfated saponins contained in the viscera of Holothuria scabra, a sea cucumber present in the Indian Ocean and abundantly consumed on the Asian food market. Using mass spectrometry, we first qualitatively and quantitatively assessed the saponin content within the viscera of H. scabra. We detected 26 sulfated saponins presenting 5 different elemental compositions. Microwave activation under alkaline conditions in aqueous solutions was developed and optimized to quantitatively and specifically induce the desulfation of the natural saponins, by a specific loss of H2SO4. By comparing the hemolytic activities of the natural and desulfated extracts, we clearly identified the sulfate function as highly responsible for the saponin toxicity.


Assuntos
Holothuria/química , Saponinas/química , Saponinas/farmacologia , Sulfatos/química , Sulfatos/farmacologia , Vísceras/química , Álcalis/química , Animais , Bovinos , Cromatografia Líquida , Hemólise/efeitos dos fármacos , Hemolíticos/análise , Hemolíticos/química , Hemolíticos/isolamento & purificação , Hemolíticos/farmacologia , Hidrólise , Oceano Índico , Micro-Ondas , Saponinas/análise , Saponinas/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Relação Estrutura-Atividade , Sulfatos/análise , Sulfatos/isolamento & purificação , Espectrometria de Massas em Tandem
4.
Pak J Pharm Sci ; 34(5(Supplementary)): 1885-1890, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34836855

RESUMO

The facile and efficient protocol for the synthesis of N-phenyl piperazine based di-thio-carbamates has been reported under neat conditions. A library of novel piperazine based di-thio-carbamates (3a-h) in excellent yields has been prepared. Solvent free, catalyst free and easy work up conditions make this protocol an attractive synthetic protocol to achieve novel biologically active di-thio-carbamates. The synthesized molecules have been characterized by FT-IR, 1HNMR and 13CNMR spectroscopic techniques. The pharmacological aspects of these derivatives have been evaluated via hemolysis and thrombolysis. All the target molecules (3a-h) exhibit mild to medium potential as hemolytic and thrombolytic agents. Among the synthesized derivatives, compound 3c showed least cytotoxicity and better thrombolytic potential.


Assuntos
Fibrinolíticos/síntese química , Fibrinolíticos/farmacologia , Química Verde/métodos , Hemolíticos/síntese química , Hemolíticos/farmacologia , Piperazinas/síntese química , Piperazinas/farmacologia , Tiocarbamatos/síntese química , Tiocarbamatos/farmacologia , Fibrinolíticos/toxicidade , Hemólise/efeitos dos fármacos , Hemolíticos/toxicidade , Humanos , Estrutura Molecular , Piperazinas/toxicidade , Relação Estrutura-Atividade , Tiocarbamatos/toxicidade
5.
Molecules ; 26(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34576946

RESUMO

A molecular umbrella composed of two O-sulfated cholic acid residues was applied for the construction of conjugates with cispentacin, containing a "trimethyl lock" (TML) or o-dithiobenzylcarbamoyl moiety as a cleavable linker. Three out of five conjugates demonstrated antifungal in vitro activity against C. albicans and C. glabrata but not against C. krusei, with MIC90 values in the 0.22-0.99 mM range and were not hemolytic. Antifungal activity of the most active conjugate 24c, containing the TML-pimelate linker, was comparable to that of intact cispentacin. A structural analogue of 24c, containing the Nap-NH2 fluorescent probe, was accumulated in Candida cells, and TML-containing conjugates were cleaved in cell-free extract of C. albicans cells. These results suggest that a molecular umbrella can be successfully applied as a nanocarrier for the construction of cleavable antifungal conjugates.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/química , Cicloleucina/análogos & derivados , Portadores de Fármacos/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida glabrata/efeitos dos fármacos , Ácido Cólico/química , Cicloleucina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacologia , Eritrócitos/efeitos dos fármacos , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
6.
Amino Acids ; 53(10): 1635-1648, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482475

RESUMO

The worrisome emergence of pathogens resistant to conventional drugs has stimulated the search for new classes of antimicrobial and antiparasitic agents from natural sources. Antimicrobial peptides (AMPs), acting through mechanisms that do not rely on the interaction with a specific receptor, provide new possibilities for the development of drugs against resistant organisms. This study sought to purify and proteomically characterize the antimicrobial and antiparasitic peptidomes of B. atrox and B. jararacussu snake venoms against Gram-positive (Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus-MRSA), Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) bacteria, and the protozoan parasites Leishmania amazonensis and Plasmodium falciparum (clone W2, resistant to chloroquine). To this end, B. atrox and B. jararacussu venom peptides were purified by combination of 3 kDa cut-off Amicon® ultracentrifugal filters and reverse-phase high-performance liquid chromatography, and then identified by electrospray-ionization Ion-Trap/Time-of-Flight mass spectrometry. Fourteen distinct peptides, with masses ranging from 443.17 to 1383.73 Da and primary structure between 3 and 13 amino acid residues, were sequenced. Among them, 13 contained unique sequences, including 4 novel bradykinin-potentiating-like peptides (BPPs), and a snake venom metalloproteinase tripeptide inhibitor (SVMPi). Although commonly found in Viperidae venoms, except for Bax-12, the BPPs and SVMPi here reported had not been described in B. atrox and B. jararacussu venoms. Among the novel peptides, some exhibited bactericidal activity towards P. aeruginosa and S. aureus, had low hemolytic effect, and were devoid of antiparasitic activity. The identified novel antimicrobial peptides may be relevant in the development of new drugs for the management of multidrug-resistant Gram-negative and Gram-positive bacteria.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Venenos de Crotalídeos/química , Peptídeos/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antimaláricos/química , Antimaláricos/farmacologia , Bothrops , Venenos de Crotalídeos/isolamento & purificação , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Leishmania/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peptídeos/química , Peptídeos/isolamento & purificação , Plasmodium falciparum/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/efeitos dos fármacos
7.
Pak J Pharm Sci ; 34(1(Special)): 441-446, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34275792

RESUMO

A series of new derivatives of 4-(2-chloroethyl)morpholine hydrochloride (5) were efficiently synthesized. Briefly, different aromatic organic acids (1a-f) were refluxed to acquire respective esters (2a-f) using conc. H2SO4 as catalyst. The esters were subjected to nucleophillic substitution by monohydrated hydrazine to acquire hydrazides (3a-f). The hydrazides were cyclized with CS2 in the presence of KOH to yield corresponding oxadiazoles (4a-f). Finally, the derivatives, 6a-f, were prepared by reacting oxadiazoles (4a-f) with 5 using NaH as activator. Structures of all the derivatives were elucidated through 1D-NMR EI-MS and IR spectral data. All these molecules were subjected to antibacterial and hemolytic activities and showed good antibacterial and hemolytic potential relative to the reference standards.


Assuntos
Antibacterianos/química , Hemolíticos/química , Morfolinas/química , Oxidiazóis/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Hemolíticos/síntese química , Hemolíticos/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Morfolinas/síntese química , Morfolinas/farmacologia , Oxidiazóis/síntese química , Oxidiazóis/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhi/efeitos dos fármacos , Espectrofotometria Infravermelho , Staphylococcus aureus/efeitos dos fármacos
8.
Biochem Pharmacol ; 192: 114693, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34302796

RESUMO

In the face of increasing drug resistance, the development of new anthelmintics is critical for controlling nematodes that parasitise livestock. Although hymenopteran venom toxins have attracted attention for applications in agriculture and medicine, few studies have explored their potential as anthelmintics. Here we assessed hymenopteran venoms as a possible source of new anthelmintic compounds by screening a panel of ten hymenopteran venoms against Haemonchus contortus, a major pathogenic nematode of ruminants. Using bioassay-guided fractionation coupled with liquid chromatography-tandem mass spectrometry, we identified four novel anthelmintic peptides (ponericins) from the venom of the neotropical ant Neoponera commutata and the previously described ponericin M-PONTX-Na1b from Neoponera apicalis venom. These peptides inhibit H. contortus development with IC50 values of 2.8-5.6 µM. Circular dichroism spectropolarimetry indicated that the ponericins are unstructured in aqueous solution but adopt α-helical conformations in lipid mimetic environments. We show that the ponericins induce non-specific membrane perturbation, which confers broad-spectrum antimicrobial, insecticidal, cytotoxic, hemolytic, and algogenic activities, with activity across all assays typically correlated. We also show for the first time that ponericins induce spontaneous pain behaviour when injected in mice. We propose that the broad-spectrum activity of the ponericins enables them to play both a predatory and defensive role in neoponeran ants, consistent with their high abundance in venom. This study reveals a broader functionality for ponericins than previously assumed, and highlights both the opportunities and challenges in pursuing ant venom peptides as potential therapeutics.


Assuntos
Venenos de Formiga/farmacologia , Anti-Helmínticos/farmacologia , Anti-Infecciosos/farmacologia , Hemolíticos/farmacologia , Inseticidas/farmacologia , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Venenos de Formiga/genética , Venenos de Formiga/isolamento & purificação , Anti-Helmínticos/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Formigas , Brugia Malayi/efeitos dos fármacos , Brugia Malayi/fisiologia , Calliphoridae , Relação Dose-Resposta a Droga , Células HEK293 , Haemonchus/efeitos dos fármacos , Haemonchus/fisiologia , Hemolíticos/isolamento & purificação , Humanos , Inseticidas/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/genética , Peptídeos/isolamento & purificação , Ovinos
9.
Peptides ; 141: 170553, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33862164

RESUMO

Six peptides, belonging to the NDBP-4 family of scorpion antimicrobial peptides were structurally and functionally characterized. The sequence of the mature peptides VpCT1, VpCT2, VpCT3 and VpCT4 was inferred by transcriptomic analysis of the venom gland of the scorpion Mesomexovis variegatus. Analysis of their amino acid sequences revealed patterns that are also present in previously reported peptides that show differences in their hemolytic and antimicrobial activities in vitro. Two other variants, VpCT3W and VpCTConsensus were designed to evaluate the effect of sequence changes of interest on their structure and activity. The synthesized peptides were evaluated by circular dichroism to confirm their α-helical conformation in a folding promoting medium. The peptides were assayed on two Gram-positive and three Gram-negative bacterial strains, and on two yeast strains. They preferentially inhibited the growth of Staphylococcus aureus, were mostly ineffective on Pseudomonas aeruginosa, and moderately inhibited the growth of Candida yeasts. All six peptides exhibited hemolytic activity on human erythrocytes in the range of 4.8-83.7 µM. VpCT3W displayed increased hemolytic and anti-yeast activities, but showed no change in antibacterial activity, relative to its parental peptide, suggesting that Trp6 may potentiate the interaction of VpCT3 with eukaryotic cell membranes. VpCTConsensus showed broader and enhanced antimicrobial activity relative to several of the natural peptides. The results presented here contribute new information on the structure and function of NDBP-4 antimicrobial peptides and provides clues for the design of less hemolytic and more effective antimicrobial peptides.


Assuntos
Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Escorpiões/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Peptídeos Antimicrobianos/síntese química , Dicroísmo Circular , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
10.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33688047

RESUMO

The mosquito protein AEG12 is up-regulated in response to blood meals and flavivirus infection though its function remained elusive. Here, we determine the three-dimensional structure of AEG12 and describe the binding specificity of acyl-chain ligands within its large central hydrophobic cavity. We show that AEG12 displays hemolytic and cytolytic activity by selectively delivering unsaturated fatty acid cargoes into phosphatidylcholine-rich lipid bilayers. This property of AEG12 also enables it to inhibit replication of enveloped viruses such as Dengue and Zika viruses at low micromolar concentrations. Weaker inhibition was observed against more distantly related coronaviruses and lentivirus, while no inhibition was observed against the nonenveloped virus adeno-associated virus. Together, our results uncover the mechanistic understanding of AEG12 function and provide the necessary implications for its use as a broad-spectrum therapeutic against cellular and viral targets.


Assuntos
Antivirais/metabolismo , Hemolíticos/metabolismo , Proteínas de Insetos/metabolismo , Lipídeos , Animais , Antivirais/química , Antivirais/farmacologia , Linhagem Celular , Membrana Celular/metabolismo , Culicidae , Eritrócitos/efeitos dos fármacos , Ácidos Graxos Insaturados/metabolismo , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Insetos/química , Proteínas de Insetos/farmacologia , Ligantes , Lipídeos/química , Ligação Proteica , Estrutura Terciária de Proteína , Envelope Viral/metabolismo , Vírus/efeitos dos fármacos , Vírus/metabolismo
11.
Biomolecules ; 10(9)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872343

RESUMO

The peptides from the ranacyclin family share similar active disulphide loop with plant-derived Bowman-Birk type inhibitors, some of which have the dual activities of trypsin inhibition and antimicrobial. Herein, a novel Bowman-Birk type trypsin inhibitor of the ranacyclin family was identified from the skin secretion of broad-folded frog (Sylvirana latouchii) by molecular cloning method and named as SL-BBI. After chemical synthesis, it was proved to be a potent inhibitor of trypsin with a Ki value of 230.5 nM and showed weak antimicrobial activity against tested microorganisms. Modified analogue K-SL maintains the original inhibitory activity with a Ki value of 77.27 nM while enhancing the antimicrobial activity. After the substitution of active P1 site to phenylalanine and P2' site to isoleucine, F-SL regenerated its inhibitory activity on chymotrypsin with a Ki value of 309.3 nM and exhibited antiproliferative effects on PC-3, MCF-7 and a series of non-small cell lung cancer cell lines without cell membrane damage. The affinity of F-SL for the ß subunits in the yeast 20S proteasome showed by molecular docking simulations enriched the understanding of the possible action mode of Bowman-Birk type inhibitors. Further mechanistic studies have shown that F-SL can activate caspase 3/7 in H157 cells and induce apoptosis, which means it has the potential to become an anticancer agent.


Assuntos
Antineoplásicos/isolamento & purificação , Ranidae/metabolismo , Inibidores da Tripsina/isolamento & purificação , Motivos de Aminoácidos , Animais , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Quimotripsina/antagonistas & inibidores , Ensaios de Seleção de Medicamentos Antitumorais , Hemolíticos/química , Hemolíticos/isolamento & purificação , Hemolíticos/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores da Tripsina/síntese química , Inibidores da Tripsina/farmacologia
12.
Sci Rep ; 10(1): 11168, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32636484

RESUMO

The objective of the study was a comparative analysis of the antihemolytic activity against two Staphylococcus aureus strains (8325-4 and NCTC 5655) as well as α-hemolysin and of the membrane modifying action of four hydrolysable tannins with different molecular mass and flexibility: 3,6-bis-O-di-O-galloyl-1,2,4-tri-O-galloyl-ß-D-glucose (T1), 1,2,3,4,5-penta-O-galloyl-ß-D-glucose (T2), 3-O-galloyl-1,2-valoneoyl-ß-D-glucose (T3) and 1,2-di-O-galloyl-4,6-valoneoyl-ß-D-glucose (T4). We showed that all the compounds studied manifested antihemolytic effects in the range of 5-50 µM concentrations. However, the degree of the reduction of hemolysis by the investigated tannins was not uniform. A valoneoyl group-containing compounds (T3 and T4) were less active. Inhibition of the hemolysis induced by α-hemolysin was also noticed on preincubated with the tannins and subsequently washed erythrocytes. In this case the efficiency again depended on the tannin structure and could be represented by the following order: T1 > T2 > T4 > T3. We also found a relationship between the degree of antihemolytic activity of the tannins studied and their capacity to increase the ordering parameter of the erythrocyte membrane outer layer and to change zeta potential. Overall, our study showed a potential of the T1 and T2 tannins as anti-virulence agents. The results of this study using tannins with different combinations of molecular mass and flexibility shed additional light on the role of tannin structure in activity manifestation.


Assuntos
Proteínas Hemolisinas/farmacologia , Hemólise/efeitos dos fármacos , Hemolíticos/farmacologia , Extratos Vegetais/farmacologia , Taninos/farmacologia , Animais , Membrana Eritrocítica/efeitos dos fármacos , Euphorbiaceae/química , Ácido Gálico/análogos & derivados , Glucose/análogos & derivados , Extratos Vegetais/química , Ovinos , Staphylococcus aureus/enzimologia , Taninos/química
13.
Sci Rep ; 10(1): 10869, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616760

RESUMO

The growing prevalence of resistance to antibiotics motivates the search for new antibacterial agents. Antimicrobial peptides are a diverse class of well-studied membrane-active peptides which function as part of the innate host defence system, and form a promising avenue in antibiotic drug research. Some antimicrobial peptides exhibit toxicity against eukaryotic membranes, typically characterised by hemolytic activity assays, but currently, the understanding of what differentiates hemolytic and non-hemolytic peptides is limited. This study leverages advances in machine learning research to produce a novel artificial neural network classifier for the prediction of hemolytic activity from a peptide's primary sequence. The classifier achieves best-in-class performance, with cross-validated accuracy of [Formula: see text] and Matthews correlation coefficient of 0.71. This innovative classifier is available as a web server at https://research.timmons.eu/happenn , allowing the research community to utilise it for in silico screening of peptide drug candidates for high therapeutic efficacies.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Hemólise/efeitos dos fármacos , Hemolíticos/farmacologia , Aprendizado de Máquina , Redes Neurais de Computação , Software , Peptídeos Catiônicos Antimicrobianos/química , Simulação por Computador , Hemolíticos/química , Humanos , Análise de Sequência de Proteína
14.
Pak J Pharm Sci ; 32(5): 2003-2010, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31813864

RESUMO

The aims of the present investigation were to assess the antibacterial, antifungal, enzyme inhibition and hemolytic activities of various fractions of Rhynchosia pseudo-cajan Cambess. The methanolic extract of the plant was dissolved in the water (distilled) and then partitioned with the n-hexane, chloroform, EtOAc and n-BuOH sequentially. Antibacterial activity was checked against Escherichia coli, Pasturella multocida, Bacillus subtilis and Staphylococcus aureus by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Chloroform and ethyl acetate soluble fractions showed good activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. These fractions also showed good MIC values. The n-butanol soluble and remaining aqueous fraction also showed good activity against some strains. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the disc diffusion method using fluconazole, a standard antifungal drug, as positive control. Chloroform, n-butanol and ethyl acetate soluble fraction showed good activity only against G. lucidum. Enzyme inhibition studies were done against four enzymes i.e. α-glucosidase, butyrylcholinesterase, acetyl cholinesterase and lipoxygenase. Aqueous fraction possessed very good activity against α-glucosidase, even greater than acarbose, a reference standard drug. Its IC50 value was found as 29.81±0.12 µg/ml as compared to acarbose having IC50 38.62±0.04 µg/ml. Chlroform and ethyl acetate soluble fractions also showed good activity against α-glucosidase. Ethyl acetate soluble and remaining aqueous fractions showed good activity against lipoxygenase. All the studied fractions showed very less toxicity i.e. <2.5%.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Fabaceae/química , Hemólise/efeitos dos fármacos , Hemolíticos/farmacologia , Extratos Vegetais/farmacologia , 1-Butanol/química , Bactérias/efeitos dos fármacos , Clorofórmio/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Fungos/efeitos dos fármacos , Hexanos/química , Testes de Sensibilidade Microbiana/métodos , Fitoterapia/métodos
15.
Pol J Microbiol ; 68(3): 383-390, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31880884

RESUMO

Antimicrobial peptides (AMPs) are cationic small peptide chains that have good antimicrobial activity against a variety of bacteria, fungi, and viruses. AMP-17 is a recombinant insect AMP obtained by a prokaryotic expression system. However, the full antifungal activity, physicochemical characteristics, and cytotoxicity of AMP-17 were previously unknown. AMP-17 was shown to have good antifungal activity against five pathogenic fungi, with minimum inhibitory concentrations (MIC) of 9.375-18.75 µg/ml, and minimum fungicidal concentrations (MFC) of 18.75-37.5 µg/ml. Notably, the antifungal activity of AMP-17 against Cryptococcus neoformans was superior to that of other Candida spp. In addition, the hemolytic rate of AMP-17 was only 1.47%, even at the high concentration of 16× MIC. AMP-17 was insensitive to temperature and high salt ion concentration, with temperatures of 98°C and -80°C, and NaCl and MgCl2 concentrations of 50-200 mmol/l, having no significant effect on antifungal activity. However, AMP-17 was sensitive to proteases, trypsin, pepsin, and proteinase K. The elucidation of antifungal activity, physicochemical properties and cytotoxicity of AMP-17 provided an experimental basis for its safety evaluation and application, as well as indicated that AMP-17 might be a promising drug.Antimicrobial peptides (AMPs) are cationic small peptide chains that have good antimicrobial activity against a variety of bacteria, fungi, and viruses. AMP-17 is a recombinant insect AMP obtained by a prokaryotic expression system. However, the full antifungal activity, physicochemical characteristics, and cytotoxicity of AMP-17 were previously unknown. AMP-17 was shown to have good antifungal activity against five pathogenic fungi, with minimum inhibitory concentrations (MIC) of 9.375­18.75 µg/ml, and minimum fungicidal concentrations (MFC) of 18.75­37.5 µg/ml. Notably, the antifungal activity of AMP-17 against Cryptococcus neoformans was superior to that of other Candida spp. In addition, the hemolytic rate of AMP-17 was only 1.47%, even at the high concentration of 16× MIC. AMP-17 was insensitive to temperature and high salt ion concentration, with temperatures of 98°C and ­80°C, and NaCl and MgCl2 concentrations of 50­200 mmol/l, having no significant effect on antifungal activity. However, AMP-17 was sensitive to proteases, trypsin, pepsin, and proteinase K. The elucidation of antifungal activity, physicochemical properties and cytotoxicity of AMP-17 provided an experimental basis for its safety evaluation and application, as well as indicated that AMP-17 might be a promising drug.


Assuntos
Antifúngicos/farmacologia , Moscas Domésticas/química , Peptídeos/farmacologia , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Fungos/efeitos dos fármacos , Hemolíticos/química , Hemolíticos/isolamento & purificação , Hemolíticos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Peptídeos/química , Peptídeos/isolamento & purificação
16.
Org Lett ; 21(16): 6432-6436, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31386380

RESUMO

Lysobacter are ubiquitous in the environment but remain largely underexplored, although the bacteria are considered "peptide specialists". Here, we identified a new cyclic lipodepsipeptide, WBP-29479A1 (1), through genome mining of L. antibioticus ATCC 29479. 1 is biosynthesized by a large NRPS gene cluster, and its structure, including the six nonproteinogenic residues and 3-hydroxy fatty acid, was determined by extensive spectroscopic analyses and chemical derivatization. 1 exhibits potent anti-MRSA activity in a menaquinone-dependent manner.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Lysobacter/genética , Antibacterianos/metabolismo , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Genoma Bacteriano , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Lysobacter/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Família Multigênica , Mutação , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Valina
17.
Mater Sci Eng C Mater Biol Appl ; 103: 109740, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349401

RESUMO

To overcome the disadvantages of chemical and physical methods, phyto-fabricated nanoparticles attained great attention due to their multifarious applications. Here we successfully demonstrated Papaver somniferum L. mediated green synthesis of lead oxide (PbO) and iron oxide (Fe2O3) nanoparticles. Characterization of nanoparticles involved techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and energy dispersive X-ray (EDX) associated with scanning electron microscopy (SEM). XRD analysis confirmed the phase identification and crystalline nature. FTIR analysis confirmed the capping of nanoparticles by plants' phytochemicals. SEM revealed morphological features of PbO and Fe2O3 with size of nanoparticles being 23 ±â€¯11 nm and 38 ±â€¯13 nm, respectively. The elemental composition of the nanoparticles was confirmed by EDX. Both bacterial and fungal isolates showed susceptibility towards PbO and Fe2O3 NPs. Both the NPs also showed considerable total antioxidant potential, free radical scavenging potential and reducing power. Insignificant level of α-amylase for both NPs was observed. Fe2O3 NPs showed superior biocompatibility with human RBCs as compared to PbO whereas PbO showed more potent anti-cancer activity as compared to Fe2O3 NPs. Overall our study concluded that both NPs played vital role in multiple biological assays however, extensive research focused on cytotoxic evaluation of NPs in-vivo is required.


Assuntos
Compostos Férricos/química , Chumbo/química , Nanopartículas Metálicas/química , Óxidos/química , Papaver/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Eritrócitos/efeitos dos fármacos , Hemolíticos/química , Hemolíticos/farmacologia , Células Hep G2 , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Nanopartículas Metálicas/uso terapêutico , Papaver/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
18.
J Appl Microbiol ; 127(2): 481-494, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31141277

RESUMO

AIM: The aim of present work was to explore the potential of Chlorella sp. SRD3 extracts for antioxidant and antibacterial activity along with the evaluation of minimum inhibitory concentration (MIC) and haemolytic activity to detect RBC cell damage. METHODS AND RESULTS: Screening and isolation of microalgae was performed using bold basal medium under normal illuminance (at 27°C) and microscopic observation. Growth of the microalgae was optimized using a different medium and light source. The isolated microalgae incubated under fluorescent light when cultured in F/2 medium showed a highest dry biomass yield of 3·77 ± 0·1 g l-1 , when compared to the growth under direct sunlight (2·74 ± 0·07 g dwt l-1 ). The quantitative analysis of extracts revealed higher phenols, flavonoids and proanthocyanidins in ethyl acetate and hexane extracts followed by methanol. The antioxidant activity of extracts was tested against 1-diphenyl-2-picrylhydrazyl and ABTS radical, its reducing power assay was performed. From antibacterial activity, the two extracts showed better inhibition against Gram-negative bacteria. Also, they resulted in very low MIC values with effective activity against pathogens. In haemolytic activity, no haemolysis occurred, when the concentration (µg ml-1 ) was below 64 for methanol and 32 for ethyl acetate extract. In addition, Chlorella sp. extracts were characterized by GC-MS analysis to detect the major compounds. CONCLUSION: The polar extracts revealed satisfactory results against the clinical isolates and the compounds responsible were reflected in the GC-MS spectrum. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study revealed significant biological potentials of the green alga, Chlorella sp. such as antioxidant, antibacterial and hemolytic activities. Therefore, this vital source might serve as a cost-effective, alternative choice to the pharmaceutical and food industries in the near future.


Assuntos
Antibacterianos/farmacologia , Chlorella , Sequestradores de Radicais Livres/farmacologia , Antibacterianos/química , Chlorella/química , Chlorella/crescimento & desenvolvimento , Flavonoides/análise , Sequestradores de Radicais Livres/química , Bactérias Gram-Negativas/efeitos dos fármacos , Hemolíticos/farmacologia , Humanos , Fenóis/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proantocianidinas/análise
19.
Pak J Pharm Sci ; 32(2 (Supplementary)): 831-837, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31103979

RESUMO

In the present communication, synthesis of bis-pyrazolones containing aryl motifs (4-14) and their α-glucosidase inhibitory activity, hemolytic and antihemolytic activities were reported. The newly synthesized compounds were characterized by analytical techniques such 1H-NMR, 13C-NMR, IR, mass spectrometry and compound No 4 additionally by X-ray crystallography. Compounds 4, 12, 14 were obtained in more than 85% yield. In comparison to typical acarbose (IC50 = 37.38±0.12µM), all synthesized compounds showed potent activity with IC50 values between 31.26±0.11 to 396.25±0.18µM. The most potent compounds 6, 8 and 11 showed IC50 values within the range of 31.26±0.11 to 37.48±0.12µM. Compounds 7, 10, 12 and 13 showed IC50 values within the range of 65.23±0.12 to 154.87±0.16µM, while compounds 4, 5 and 9 showed moderate inhibition with IC50 values 286.56±0.16 to 396.25±0.18µM. Structure-activity relationship (SAR) studies, suggests that electron withdrawing groups played a crucial role in enhancing α-glucosidase inhibitory effects of title compounds. In addition, results of the hemolytic and antihemolytic activity studies indicated that compound 13 possessed moderate levels of hemolytic and highest anti- hemolytic activity while 8 showed low anti- hemolytic and high hemolytic activity.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hemolíticos/química , Hemolíticos/farmacologia , Pirazóis/síntese química , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Hemólise/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Pirazóis/química , Pirazóis/farmacologia , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
20.
Pak J Pharm Sci ; 32(2): 697-702, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31081785

RESUMO

The present investigation was undertaken to evaluate the antibacterial, antifungal and hemolytic activities of organic and aqueous fractions of Fumaria indica, Dicliptera bupleuroides and Curcuma zedoaria. The methanolic extracts of the plants were dissolved in the water (distilled) separately and then partitioned with the n-hexane, CHCl3, EtOAc and n-BuOH sequentially. Antibacterial activity was checked against Escherichia coli, Pasturella multocida, Bacillus subtilis and Staphylococcus aureus by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the disc diffusion method using fluconazole, a standard antifungal drug, as positive control. It was revealed that aqueous fraction of F. indica showed very good antibacterial activity against P. multocida with zone of inhibition 26mm and MIC of 98µg/mL. Its CHCl3 and n-BuOH fractions also displayed good results. Its CHCl3 fraction showed good antifungal activity against G. lucidum with zone of inhibition 24mm and MIC of 115µg/mL. Other polar fractions of F. indica showed good activity against somefungal strains. The CHCl3 and EtOAc fractions of D. bupleuroides displayed good antibacterial activity against some bacterial strains. Its EtOAc fraction showed good antifungal activity only against G. lucidum. The CHCl3 fraction of C. zedoaria showed good activity against all studied bacterial strains, while its EtOAc and n-BuOH fractions displayed good results against some bacterial strains. None of the fractions of C. zedoaria displayed antifungal activity against the under test strains. All the studied fractions of three plants showed very less toxicity except n-hexane fraction of D. bupleuroides which showed 79% toxicity.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Hemolíticos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Acanthaceae/química , Antibacterianos/química , Antifúngicos/química , Curcuma/química , Avaliação Pré-Clínica de Medicamentos , Fumaria/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Hemolíticos/química , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
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