Antibacterial and anti-biofilm potential of Plectranthus amboinicus (Lour) Spreng essential oil and Carvacrol against Staphylococcus aureus and Escherichia coli / Potencial antibacteriano e anti-biofilme do óleo essencial de Plectranthus amboinicus (Lour) Spreng e carvacrol frente a Staphylococcus aureus e Escherichia coli

Introduction: Staphylococcus aureus and Escherichia coli are pathogens that cause chronic infections due to antibiotic resistance mechanisms and their ability to adhere to surfaces and to form biofilms. The search for new agents from natural resources to counter microbial biofilms is an urgent priority in healthcare. Objetive: chemical composition, antibacterial and anti-biofilm activity of Plectranthus amboinicus essential oil (PAEO) and carvacrol were investigated against E. coli and S. aureus. Methodology: PAEO was chemically analyzed using gas chromatography coupled to a mass spectrometer. Antimicrobial activity was assessed by the disc diffusion method and broth microdilution method to determine minimum inhibitory concentrations (MICs). Antibiofilm activity was investigated using 96-well plates with a crystal violet assay. Results: carvacrol (85.25%) was the major component of PAEO. The disc diffusion test confirmed the ability of PAEO and carvacrol in inhibiting bacteria in their planktonic form. The MICs of PAEO against S. aureus and E. coli were 0.31 and 1.25%, respectively, with bactericidal effect. Carvacrol demonstrated a significant antibacterial property (MIC = 0.31%), exhibiting bacteriostatic effects against S. aureus and bactericidal effects against E. coli. Carvacrol considerably inhibited E. coli biofilm formations (58.9%). Moreover, carvacrol inactivated the mature biofilms. Conclusion: the data obtained are promising, and facilitates the development of new therapeutic alternatives. These results indicate the potential of carvacrol in treating diseases caused by E. coli and S. aureus

Introdução: Escherichia coli e Staphylococcus aureus são patógenos que podem causar infecções persistentes devido aos mecanismos de resistência e à sua capacidade de aderir e formar biofilme. A busca por novos agentes a partir de recursos naturais para combater o biofilme é uma prioridade na área da saúde. Objetivo: a composição química, a atividade antibacteriana e anti-biofilme do óleo essencial de Plectranthus amboinicus (PAEO) e do carvacrol foram investigadas frente a S. aureus e E. coli. Metodologia: a análise química do PAEO foi realizada por cromatografia gasosa acoplada a espectrômetro de massa. A atividade antimicrobiana foi avaliada por difusão em disco e microdiluição em caldo para determinar as concentrações inibitórias mínimas (CIMs). As atividades do anti-biofilme foram investigadas usando placas de 96 poços pelo ensaio de cristal violeta. Resultados: o carvacrol (85,25%) foi o principal componente do PAEO. A capacidade do PAEO e do carvacrol para inibir bactérias planctônica foi confirmada por difusão em disco. A CIM do PAEO para S. aureus e E. coli foi de 0,31 e 1,25%, respectivamente, com efeito bactericida. O carvacrol demonstrou uma propriedade antibacteriana significativa (CIM=0,31%), exibindo efeito bacteriostático frente a S. aureus e efeito bactericida para E. coli. O carvacrol inibiu significativamente a formação de biofilme de E. coli (58,9%) e promoveu a desestabilização do biofilme maduro. Conclusão: os dados obtidos são promissores, possibilitando o desenvolvimento de novas alternativas terapêuticas e revelam a potencialidade do carvacrol como fonte para o tratamento de doenças causadas por E. coli e S. aureus.

Phytochemical characterization and biological activities of Plectranthus barbatus Andrews / Caracterização fitoquímica e atividades biológicas de Plectranthus barbatus Andrews

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.

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.

Evaluation of tissue repair using phytotherapeutic gel from Plectranthus neochilus, Schlechter (boldo-gambá) and Cnidoscolus quercifolius Pohl (favela) in Wistar rats / [Avaliação da reparação tecidual do gel fitoterápico de Plectranthus neochilus, Schlechter (Boldo-gambá) e Cnidoscolus quercifolius Pohl (Favela) em ratos Wistar]

The objective of this study was to investigate the effects of a gel formulation from the association of Plectranthus neochilus and Cnidoscolus quercifolius on tissue repair in cutaneous wounds in rats. A surgical wound was induced in 35 Wistar rats and treated according to group: G1 - commercial phytotherapeutic gel; G2 - Carbopol gel 1%; G3, 4, 5 - gel formulation from Boldo-gambá and Favela (FGBF) at 2.5%, 5%, and 10%, respectively. 1ml of the product was applied topically daily, for 14 days. Macroscopic evaluation of the wound showed inflammation, granulation, and epithelization in all groups. The FGBF 2.5% group showed greater angiogenic potential. There was a significant difference between the surgical area of the wounds treated with FGBF 2.5%, 5%, or 10% compared to the group with the commercial phytotherapeutic gel. On histomorphometry of the skin, there were reepithelization of the epidermis and superficial dermis, longitudinal collagen fibers, fibroblasts, and blood vessels, and in the deeper dermis, fibroblasts, transverse and longitudinal collagen fibers, blood vessels, and inflammatory cells. The 2.5% formulation had the greatest increase in fibroblast proliferation and most intense collagenization on day 14 of treatment.(AU)

Este trabalho objetivou investigar os efeitos de uma formulação em gel da associação da Plectranthus neochilus e da Cnidoscolus quercifolius no processo de reparação tecidual em feridas cutâneas de ratos. Foi induzida uma ferida cirúrgica em 35 ratos Wistar, sendo tratadas de acordo com os grupos: G1 - fitoterápico comercial; G2 - gel de carbopol 1%; G3, G4 e G5 - formulação gel boldo-gambá mais favela (FGBF) 2,5%, 5% e 10%, respectivamente. Aplicou-se 1mL do produto, via tópica, diariamente, durante 14 dias. Na avaliação macroscópica das feridas, verificou-se inflamação, granulação e epitelização em todos os grupos. O grupo FGBF 2,5% apresentou maior potencial angiogênico. Houve diferença significativa entre as áreas cirúrgicas das feridas tratadas com os FGBF 2,5%, 5% ou 10%, comparados ao grupo com o gel fitoterápico comercial. Na histomorfometria da pele, observou-se reepitelização da epiderme e da derme superficial, fibras colágenas longitudinais, fibroblastos e vasos sanguíneos e, na derme profunda, fibroblastos, fibras colágenas transversais e longitudinais, vasos sanguíneos e células inflamatórias. A formulação a 2,5% teve o maior aumento na proliferação de fibroblastos e mais intensa colagenização no dia 14 de tratamento.(AU)

Ethnobotany of Plectranthus neochilus Schltr (Meprobamate) in Cuba / Estudio etnobotánico de Plectranthus neochilus Schltr (Meprobamato) en Cuba

Chloroform extract (CE) and fractions obtained from Aldama arenaria roots were evaluated for their in vitro antiproliferative activity against 10 human tumor cell lines [leukemia (K-562), breast (MCF-7), ovary expressing a multidrug-resistant phenotype (NCI/ADR-RES), melanoma (UACC-62), lung (NCI-H460), prostate (PC-3), colon (HT29), ovary (OVCAR-3), glioma (U251), and kidney (786-0)]. CE presented weak to moderate antiproliferative activity (mean log GI50 1.07), whereas fractions 3 and 4, enriched with pimaranetype diterpenes [ent-pimara-8(14),15-dien-19-oic acid and ent-8(14),15-pimaradien-3ß-ol], presented moderate to potent activity for most cell lines, with mean log GI50 of 0.62 and 0.59, respectively. The results showed promising in vitro antiproliferative action of the samples obtained from A. arenaria, with the best results for NCI/ADR-RES, HT29, and OVCAR-3, and TGI values ranging from 5.95 to 28.71 µg.ml -1, demonstrating that compounds of this class may be potential prototypes for the discovery of new therapeutic agents.

El extracto de cloroformo (CE) y las fracciones obtenidas de las raíces de Aldama arenaria fueron evaluadas por su actividad antiproliferativa in vitro contra 10 líneas celulares tumorales humanas [leucemia (K-562), mama (MCF-7), ovario que expresa un fenotipo resistente a múltiples fármacos (NCI/ADR-RES), melanoma (UACC-62), pulmón (NCI-H460), próstata (PC-3), colon (HT29), ovario (OVCAR-3), glioma (U251) y riñón (786-0)]. CE presentó actividad antiproliferativa débil a moderada (log GI50 promedio de 1.07), mientras que las fracciones 3 y 4, enriquecidas con diterpenos de tipo pimarane [ent-pimara-8 (14), ácido 15-dien-19-oico y ent-8 (14), 15-pimaradien-3ß-ol], presentaron actividad moderada a potente para la mayoría de las líneas celulares, con un log GI50 promedio de 0.62 y 0.59, respectivamente. Los resultados mostraron una prometedora acción antiproliferativa in vitro de las muestras obtenidas de A. arenaria, con los mejores resultados para NCI/ADR-RES, HT29 y OVCAR-3, y valores de TGI que van desde 5.95 a 28.71 µg.ml -1, lo que demuestra que los compuestos de esta clase pueden ser prototipos potenciales para el descubrimiento de nuevos agentes terapéuticos.

Pretreatment of hepatetctomized rats with Coleus forskohlii did not interfere with the course of hepatic hyperplasia

Abstract Purpose Coleus forskohlii Briq., a medicinal plant originally from India, has been indicated against heart disease, expiratory disorders, convulsions, and hepatic changes, among others. In view of the broad pharmacological potential of the plant and the scarce information about its effects, the objective of the present study was to investigate the effect of its use for pretreatment of partially hepatectomized rats. Methods The animals were divided into two experimental groups: Control (CG) receiving physiological saline for 10 days before partial hepatetctomy, and Treated (TG) receiving 40 mg Coleus forskohlii/kg/day for 10 days before partial hepatectomy. The treatments were performed by gastric gavage. After the surgical procedure, treatment was continued according to the following groups: CG 24 h, CG 48 h, TG 24 h, and TG 48 hs, and liver tissue and intracardiac blood samples were obtained for histological and biochemical analysis, respectively. Results No significant differences were observed in mitotic or apoptotic index or in the concentrations of the enzymes AST, ALT and alkaline phosphatase, and no areas of fibrosis were detected. Conclusion Treatment with Coleus forskohlii did not interfere with the course of hepatic hyperplasia.

Antibiotic activity of Plectranthus ornatus Codd, a Traditional Medicinal Plant

ABSTRACT The dichloromethane extract of Plectranthus ornatus Codd., a tradicional medicinal plant, showed antibiotic activity with minimum inhibitory concentration (MIC) values of 0.4 mg.mL-1 and 100 percent of biofilm inhibition against Staphylococcus aureus strains isolated from animals with mastitis infections. Based on these antibacterial activities, in addition to ethnopharmacological reports from healing men and farmers in Brazil, an herbal soap was produced from this active extract and was tested both in vitro and in vivo. In vivo assays conducted on these herbal soaps led to results similar to those previously conducted with the active extract. These results indicated the great potential of this plant for use as an excipient by preparing herbal antibacterial soaps as an alternative veterinary medicine aimed at controlling bovine mastitis infections on small Brazilian farms.

Chemical composition and antimicrobial activity of the essential oil of Plectranthus mollis (Lamiaceae) from Western Ghats region, Karnataka, India / Composición química y actividad antimicrobiana del aceite esencial de Plectranthus mollis (Lamiaceae) de la región de los Ghats occidentales, Karnataka, India

Plectranthus is a large and widespread genus with a diversity of ethnobotanical uses. In traditional medicine P. mollis has been used against snakebites, respiratory stimulant and vasoconstrictor, cardiac depressant, cure for haemorrahage, treatment of mental retardation and rheumatism. P. mollis is reported to exhibit relaxant activity on smooth and skeletal muscles, and has cytotoxic and anti-tumour promoting activity, and can be used in the treatment of cancer. The aim of the present study was to identify chemical composition of the essential oil of P. mollis and to evaluate antimicrobial efficacy of the oil. The essential oil of the flowering aerial parts of P. mollis as obtained by hydro-distillation and analyzed by gas chromatography equipped with a flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). Twentyseven compounds were identified, which comprised 98.6% of the total constituents. The main compound was identified as fenchone (32.3%), followed by α-humulene (17.3%), piperitenone oxide (8.5%), cis-piperitone oxide (6.0%) and E-β-farnesene (5.9%). The oil was found rich in oxygenated monoterpenes type constituents (52.0%), followed by sesquiterpene hydrocarbons (40.2%), oxygenated sesquiterpenes (4.9%), and monoterpene hydrocarbons (1.5%). Antimicrobial activity of the essential oil of P. mollis was tested against six Gram-positive and eight Gram negative bacteria, and three fungi, by using the tube dilution method. The oil was active against the tested Gram-positive and Gram-negative bacteria, and fungi at a concentration range of 0.065±0.008-0.937±0.139mg/mL, 0.468±0.069-3.333±0.527 mg/mL and 0.117±0.0170.338±0.062mg/mL respectively. The present study revealed that the oil constituents somehow were qualitatively similar and quantitatively different than earlier reports from different parts of the world. The essential oil of P. mollis has found to be antimicrobial activity which can be usefulness in the treatment of various infectious diseases caused by bacteria and fungi.

Plectranthus es un género grande y extenso con una diversidad de usos etnobotánicos. En la medicina tradicional P.mollis se ha utilizado contra las mordeduras de serpiente, como estimulante respiratorio y vasoconstrictor, depresor cardiaco, cura para hemorragias, tratamiento del retraso mental y el reumatismo. Se informó que P. mollis presenta actividad relajante sobre los músculos lisos y esqueléticos, y tiene actividad promotora citotóxica y anti - tumoral, además puede ser utilizado en el tratamiento del cáncer. El objetivo del presente estudio fue identificar la composición química del aceite esencial de P. mollis para evaluar la eficacia antimicrobiana del aceite. El aceite esencial de las partes aéreas de las flores de P. mollis se obtuvo por hidro - destilación y se analizó por cromatografía de gases equipado con un detector de ionización de llama (GC-FID), y cromatografía de gases acoplada a espectrometría de masas (GC/MS). Se identificaron veintisiete compuestos, que comprenden el 98.6% de los constituyentes totales. El compuesto principal se identificó como fencona (32.3%), seguido de α-humuleno (17.3%), óxido de piperitenona (8.5 %), óxido de cis piperitona (6.0 %) y E-β-farneseno (5.9%). Se encontró que el aceite es rico en monoterpenos oxigenados de tipo constituyentes (52.0%), seguido de hidrocarburos de sesquiterpeno (40.2%), sesquiterpenos oxigenados (4.9%), e hidrocarburos monoterpenos (1.5 %). La actividad antimicrobiana del aceite esencial de P.mollis se ensayó frente a seis bacterias Gram-negativas y ocho Gram-positivas, y tres hongos, utilizando el método de dilución en tubo. El aceite fue activo contra las bacterias Gram-positivas y Gram-negativas y hongos ensayados, en un intervalo de concentración de 0.065±0.008 a 0.937±0.139mg/ml, 0.468±0.069 a 3.333±0.527mg/ml y 0.117±0.017 a 0.338±0.062mg/ml, respectivamente. El presente estudio reveló que los constituyentes del aceite de alguna manera fueron cualitativamente similares y cuantitativamente diferentes de los informes anteriores de diferentes partes del mundo. Se encontró que la actividad antimicrobiana del aceite esencial de P. mollis puede ser de utilidad en el tratamiento de diversas enfermedades infecciosas causadas por bacterias y hongos.

In vivo antimalarial activity of leaves of Plectranthus amboinicus (lour) spreng on Plasmodium berghei yoelii.

An invivo study of aqueous extract of the leaves of Plectranthus amboinicus on Plasmodium berghei yoelii was conducted on laboratory infected albino mice and compared with standard drug chloroquine. Reduction of parasitemia at 250 mg/kg and 500 mg/kg of aqueous extract for 24 hrs, 48 hrs, 72 hrs and 96 hrs were determined. The reduction of parasitemia after 96 hrs was 100%, 67.9% and 76.2% for standard, 250 mg/kg and 500 mg/kg of aqueous extract respectively. The isolation of active principle responsible for the reduction of parasitemia may give a promising drug molecule.