RESUMO
Background: "Dividivi" Caesalpinia coriaria (Jacq.) Willd fruits are traditionally used by the Wayuú community in La Guajira (Colombia) to treat oral and skin cavity diseases caused by bacteria and fungi. Streptococcus pyogenes is a gram-positive cocci of group A (beta-hemolytic) that is the cause of pharyngeal disease, scarlet fever, cellulitis, erysipelas, or toxic shock-like syndrome. Alternatively, Candida albicans is a yeast-like fungus that is a normal flora of the digestive tract, vagina, or skin folds; it has been known to be the root cause of opportunistic diseases such as diaper rash, oral and esophagus thrush, or vulvovaginitis. Objective: This study evaluated the antimicrobial activity of methanolic and ethanolic extracts of C. coriaria (Jacq.) Willddry fruits on S. pyogenes ATCC 12384andC. albicans ATTC 14053. Method: C. coriaria extracts were obtained from the Soxhlet method using two solvents (methanol and ethanol 98%) prepared from pulverized fruits. A phytochemical test and an antimicrobial activity assay were performed using the obtained extracts and tested using S. pyogenes ATCC 12384 and C. albicans ATTC 14053 strains. Results: A phytochemical profile was performed, examining the presence of bioactive metabolites (tannins, alkaloids, glycosides, saponins, and anthraquinones) from each extract. Antimicrobial susceptibility tests showed that the ethanolic extract inhibited S. pyogenes ATCC 12384,causing inhibition halos of 14.1 ± 0.1 mm and a Minimum Inhibitory Concentration (MIC) of 172 mg/ml, and C. albicans test shows inhibition halos of 16.1 ± 0.2 mm and MIC of 212 mg/ml. Additionally, the methanolic extract inhibited S. pyogenes with inhibition halos of 15.2 ± 0.2 mm and MIC of 152 mg/ml; no inhibitory effect was observed on C. albicans.Conclusion: This study revealed that C. coriaria has an antimicrobial effect on the tested species opening the field of its possible use as a therapeutic agent
Introducción: Los frutos del "Dividivi" Caesalpinia coriaria (Jacq.) Willd son usados tradicionalmente por la comunidad indígena Wayuú en La Guajira (Colombia) para el tratamiento de enfermedades de la cavidad bucal y cutáneas ocasionadas por bacterias y hongos. Streptococcuspyogenes es un coco grampositivo del grupo A (beta-hemolítico) que es la causa de enfermedad faríngea, escarlatina, celulitis, erisipela o síndrome tipo shock tóxico. Candida albicans es un hongo levaduriforme que es flora normal del tracto digestivo, la vagina o los pliegues de la piel; se sabe que es la causa principal de enfermedades oportunistas como la dermatitis del pañal, aftas bucales y esofágicas, o vulvovaginitis. Objetivo: El objetivo de este estudio fue evaluar la actividad antimicrobiana de extractos metanólicos y etanólicos de frutos secos sobre microorganismos patógenos específicamente S. pyogenes ATCC 12384yC. albicansATTC 14053. Método: A partir de frutos polverizados de C. coriaria, usando el método Soxlet, se evaluaron dos solventes (metanol y etanol al 98%), los cuales, fueron usados para estudiar su actividad antimicrobiana evaluando su efecto en cepas de S. pyogenes ATCC 12384 y C. albicans ATTC 14053. Resultados: Mediante un perfil fitoquímico se determinó la presencia de grupos de metabolitos secundarios con compuestos bioactivos (taninos, alcaloides, glucósidos, saponinas, y antraquinonas). Las pruebas de sensibilidad antimicrobiana mostraron que el extracto etanólico tuvo un efecto inhibidor sobre S. pyogenesATCC 12384 con halos de inhibición de 14.1 ± 0.1 mm y una concentración mínima inhibitoria (CMI) de 172 mg/mL, y sobre C. albicans se presentaron halos de inhibición de 16.1 ± 0.2 mm y CMI de 212 mg/mL, mientras que el extracto metanólico tuvo un efecto inhibidor sobre S. pyogenes con halos de inhibición de 15.2 ± 0.2 mm y CMI de 152 mg/mL no se observó efecto inhibidor sobre C. albicans. Conclusión: Este estudio demostró que C. coriaria tiene efecto antimicrobiano en las especies evaluadas, abriendo un campo de investigación en la evaluación de su uso como agente terapéutico
Assuntos
Humanos , Anti-Infecciosos , Dermatopatias , Streptococcus pyogenes , Candida albicans , Testes de Sensibilidade Microbiana , Doenças da BocaRESUMO
Bacillus thuringiensis es un bacilo Gram positivo que durante su fase de esporulación produce unainclusión parasporal, conformada por proteínas Cry con actividad biológica contra insectos-plaga. Gracias a estas proteínas Bacillus thuringiensis presenta toxicidad contra larvas de insectos-plaga de los órdenes Lepidóptera, Coleóptera y Díptera, entre otros. Además es amigable con el medioambiente, razones por la cuales se ha hecho común el uso y desarrollo de productos comerciales y plantas transgénicas a base de toxinas Cry en el sector agrícola. En esta revisión se describirá los aspectos más importantes de Bt y su aplicación como herramienta biotecnológica para el sector agrícola, con una consideración sobre bioensayos usando esta bacteria.
Bacillus thuringiensis (Bt) is a Gram-positive rod-shape bacterium that during its sporulation phase produces a parasporal inclusion formed by Cry proteins having biological activity against pest insects. Because of these proteins, Bt shows toxicity toward pest insect larvae of Lepidoptera, Coleoptera and Diptera orders among others, besides of friendly with the environment, and for this reason Bt has a very common use for commercial products and transgenic plants with Cry protein basis in agriculture. In this review is described the most important Bt factors and their application as biotechnological tool in agrobusiness, considering Bt bioassays.
Assuntos
Humanos , Biotecnologia , Bacillus thuringiensis , Uso de Praguicidas , AgriculturaRESUMO
En Colombia el cultivo de papa es el cuarto en importancia en la economía del país, y su producción alcanza las 300 millones de toneladas aproximadamente. Erwinia carotovora es una bacteria Gram negativa, anaeróbica facultativa causante de la pudrición blanda de la papa, puede llegar a generar hasta el 100% de daño en la cosecha, lo cual ocasiona grandes pérdidas económicas. Se ha establecido que la bacteria Bacillus thuringiensis es capaz de suprimir la virulencia de E. caratovora debido a que produce N-acil-homoserina-lactonasa, una potente enzima que degrada de N-acil-homoserinolactonas, que son indispensables en el mecanismo de quorum-sensing de E. caratovora. Esta circunstancia, puede ser una alternativa importante para el control de la enfermedad de la pudrición blanda de la papa. Considerando lo anterior, en este artículo se describe el proceso que emplea la bacteria Bacillus thuringiensis para inhibir la actividad de E. caratovora.
In Colombia the potato crop is the fourth in importance in the economy of the country, its production reached 300 million tons. Erwinia carotovora is a Gram-negative bacterium, facultative anaerobic which causes the soft rotting of the potato; it can potentially generate up to 100% damage in the crop, which causes large economic losses. It has been established that the bacterium Bacillus thuringiensis is able to suppress the virulence of E. caratovora because it produces N-acyl-homoserine-lactonasa, a powerful enzyme that degrades of N-acyl-homoserinolactonas, which are indispensable in the quorum-sensing mechanism of E. caratovora. This can be an important alternative for the control of the disease of the soft rotting of the potato. Considering the above, this article describes the process used by the bacterium B. thuringiensis to inhibit the activity of E. caratovora.
Assuntos
Humanos , Bacillus thuringiensis , Bactérias , Produção Agrícola , Pectobacterium carotovorumRESUMO
An emergent pest is the weevil Asymmathetes vulcanorum, an insect that attacks Colombian potato areas. Here, some Cry proteins from the entomopathogenic bacteria Bacillus thuringiensis were evaluated as biological control strategy. It was found that Cry1B protoxin caused a mortality of 40% with a dose of 8000 ng/cm(2). Also in this research, it was identified a full length cDNA of an aminopeptidase N, a possible Cry protein receptor located in the insect midgut. This is the first report about B. thuringiensis as an alternative method for control of A. vulcanorum in Colombia.
Assuntos
Antígenos CD13/genética , Proteínas Hemolisinas/genética , Controle Biológico de Vetores/métodos , Gorgulhos/genética , Animais , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Antígenos CD13/metabolismo , Proteínas Hemolisinas/metabolismo , Gorgulhos/metabolismoRESUMO
The use of Cry proteins from Bacillus thuringiensis are an important strategy for biological control. Recently it has been demonstrated that Cry hybrid proteins (by domain swapping) resulted in improved toxicities in comparison with parental proteins. Here, an SN1917 hybrid toxin was constructed and tested against Colombian pest insects Tecia solanivora (Lepidoptera: Gelechiidae), a severe potato pest, and Hypothenemus hampei (Coleoptera: Scolytidae), which attacks coffee crops. The SN1917 protoxin had a concentration causing 50% mortality (LC(50)) of 392 ng cm(-2), and SN1917 toxin showed an LC(50) of 201 ng cm(-2) against T. solanivora first instar larvae. The two parental toxins (Cry1B and Cry1I) used to make this new hybrid protein caused a mortality of 60% and 52%, respectively. Unfortunately, H. hampei first instar larvae proved to be resistant to the toxin. We conclude that SN1917 is an option for biological control and resistance management of T. solanivora. Implications for H. hampei are discussed.
Assuntos
Bacillus thuringiensis/genética , Toxinas Bacterianas/genética , Toxinas Bacterianas/farmacologia , Besouros/efeitos dos fármacos , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Larva/efeitos dos fármacos , Dose Letal Mediana , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Alinhamento de Sequência , Análise de SobrevidaRESUMO
Cry1B and Cry3 proteins from Bacillus thuringiensis are toxic to beetles such as the colorado potato beetle and the cottonwood leaf beetle. We report the development of a suitable rearing, bioassay method and the toxicity of these Cry proteins to coffee berry borer first instar larvae.
Assuntos
Proteínas de Bactérias , Besouros , Endotoxinas , Proteínas Hemolisinas , Inseticidas , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Proteínas Recombinantes de FusãoRESUMO
The Andean weevil Premnotrypes vorax represents an important cause of damage to Colombian potato crops. Due to the impact of this plague on the economy of the country, we searched for new alternatives for its biological control, based on the entomopathogenic bacteria Bacillus thuringiensis. A total of 300 B. thuringiensis strains obtained from potato plantations infested with P. vorax were analyzed through crystal morphology, SDS-PAGE, PCR and bioassays. We used site-directed mutagenesis to modify the Cry3Aa protein. Most of the B. thuringiensis isolates had a bipyramidal crystal morphology. SDS-PAGE analyses had seven strains groups with delta-endotoxins from 35 to 135 kDa. The genes cry 2 and cry 1 were significantly more frequent in the P. vorax habitat (PCR analyses). Three mutant toxins, 1 (D354E), 2 (R345A, DeltaY350, DeltaY351), and 3 (Q482A, S484A, R485A), were analyzed to assess their activity against P. vorax larvae. Toxicity was low, or absent, against P. vorax for isolates, wild type cry 3Aa and cry 3Aa mutants. The genetic characterization of the collection provides opportunities for the selection of strains to be tested in bioassays against other insect pests of agricultural importance, and for designing Cry proteins with improved insecticidal toxicity.