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1.
Braz. j. biol ; 82: e236297, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153472

RESUMO

Abstract Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Resumo Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis ​​e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

2.
Braz J Biol ; 82: e236297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787716

RESUMO

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Assuntos
Plectranthus , Animais , Arthrodermataceae , Leucócitos Mononucleares , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
3.
Tuberculosis (Edinb) ; 121: 101919, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32279875

RESUMO

This study reports the development of a new PCR-free device, using IS6110 gene as biomarker, for Tuberculosis (TB) diagnosis. An arginine film (ARGFILM) was used to prepare the biosensor platform. MT-probe was immobilized on this biosensor platform to identify IS6110 gene. This gene is an excellent biomarker for Mycobacterium tuberculosis (MT). Electrochemical analyses were carried out using differential pulse voltammetry method (DPV) by methylene blue (MB) reduction signal measurement before and after hybridization either between probe and synthetic target or extracted DNA from clinical sputum samples. The optimization study of MT-probe immobilization on modified-electrode surface showed that the best probe concentration was 15 µM. The analytical analysis of hybridization assays was performed using different concentrations of synthetic MT-target (15-500 nM). The linear response was between 15 and 100 nM and the detection limit was 4.4 nM. The biosensor performance was also investigated with extracted DNA from sputum samples (PCR-free). The results showed that the biosensor was able to detect the MT from samples, exhibiting a high sensitivity and satisfactory selectivity. Thus, these results allow for the possibility of developing a portable detection device for effective diagnosis of TB patients.

4.
J Glob Antimicrob Resist ; 3(2): 103-108, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27873657

RESUMO

The aim of this study was to determine whether encapsulation of ß-lapachone (ß-lap) into liposomes interferes with its in vitro antimicrobial activity against meticillin-resistant Staphylococcus aureus (MRSA) and Cryptococcus neoformans clinical strains. Liposomes (ß-lap:lipo or ß-lap:HPß-CD-lipo) were prepared using the hydration of thin lipid film method followed by sonication. The in vitro antimicrobial activities of ß-lap-loaded liposomes against MRSA and C. neoformans were evaluated using the microdilution method according to the Clinical and Laboratory Standards Institute (CLSI). The liposomes presented a mean particle size ranging from 88.7±1.5nm to 112.4±1.9nm with a polydispersity index ranging from 0.255 to 0.340, zeta potential from -0.26±0.01mV to +0.25±0.05mV and drug encapsulation efficiency from 97.4±0.3% to 98.9±0.4%. ß-Lap and ß-lap:HPß-CD had minimum inhibitory concentrations (MICs) ranging from 2mg/L to 4mg/L, whereas the MICs of ß-lap-lipo or ß-lap:HPß-CD-lipo ranged from 4mg/L to 16mg/L for the MRSA strains tested. ß-Lap and ß-lap:HPß-CD were able to inhibit fungal growth [MIC=2-8mg/L and minimum fungicidal concentration (MFC)=4-8mg/L]. However, ß-lap-lipo and ß-lap:HPß-CD-lipo were more efficient, with MICs and MFCs of <4mg/L. These findings suggest that the liposomal formulations tested do not interfere significantly with ß-lap antibacterial activity against MRSA and improve its antifungal properties against C. neoformans.

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