Avaliou-se a atividade antimicrobiana de 13 extratos totais, 10 brandos (B) e 3 batidos (E) elaborados a partir da folha seca e fresca da Petiveria alliacea L. Para sua preparação se empregaram vários solventes: solução hidroalcoólica 30%, 80% e álcool isopropílico. O efeito antimicrobiano dos extratos foi comprovado pelo método do Kirby-Bauer, usando para isso quatro cepas bacterianas da coleção ATCC (Escherichia coli, Staphylococcus aureus, Enterococcus faecalis e Pseudomonas aeruginosa) e um fungo leveduriforme (Candida albicans). Determinaram-se parâmetros de controle da qualidade físicos, físico-químicos e químicos dos extratos mais ativos. Obtiveram-se como resultados: que 9 extratos mostraram atividade antibacteriana, sendo os mais concentrados (B8 e E3) os de maior espectro de ação frente às bactérias provadas; o efeito dos extratos batidos (E1, E2 e E3) foi maior frente a P. aeruginosa; os extratos batidos se consideram mais ativos que os brandos e não se obteve atividade antifúngica caso algum. Determinou-se a Concentração Mínima Inhibitoria e Bactericida para ambos os extratos, resultando a primeira para os extratos brandos maior a 100 mg/mL e para as batidos maior a 50 mg/mL; a segunda para os extratos brandos maior ou igual a 400 mg/mL e para as batidos maior ou igual a 200 mg/mL, em relação à droga fresca.

The antimicrobial activity of 13 total extracts was evaluated, 10 soft extracts (B) and 3 blended extracts (E) prepared from dry and fresh leaves of Petiveria alliacea L. Various solvents were used for their preparation: hydroalcoholic solution at 30%, 80% and isopropyl alcohol. The antimicrobial effect of the extracts was tested by means of the method of Kirby-Bauer, using four bacterial strains from the ATCC collection (Escherichia coli, Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa) and a leveduriform fungus (Candida albicans). The following quality control parameters were determined for most active extracts: physical, physical-chemical and chemical parameters. The results were: nine extracts showed antibacterial activity, being the most concentrated (B8 and E3), the ones with the highest activity in the presence of the bacteria tested; the effect of blended extracts (E1, E2 and E3) was greater in the presence of P. aeruginosa. Blended extracts are considered more potent and active than soft extracts. No antifungal activity was obtained for both types of extracts. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined for both extracts, with the following results: MIC-soft extracts (>100 mg/mL), blended extracts (>50 mg/mL); MBC-soft extracts (≥400 mg/mL), blended extracts (≥200 mg/mL) based on fresh leaves.

The in vitro evaluation of the growth inhibitory activity, carried out by aerobic endospore forming bacteria (AEFB) on phythopatogenic fungi, isolated from ornamental plants, was done. The biocide activity was determined by the co-inoculation of fungi and bacterial isolates on Petri dishes containing Potato Dextrose Agar, BIOCEN. There were presented the growth inhibition curves for each fungi and a control, and it was calculated the radial growth inhibition percentage (RGIP). The 62% of the bacterial isolates generate a fungal growth inhibition area, being selected five strains with simultaneous inhibitory activity, evident after the third day of incubation. In the colonies of Curvularia lunata it was observed an internal lyses area and a dimness of the colony border next of the inhibition zone. The RGIP oscillated between 51.6 and 72.2%. The bacteria isolates description based on phenotypic characteristics, confirmed their taxonomic location in the aerobic endospore forming bacteria group, Bacilli Class

Se realizó la evaluación in vitro de la actividad inhibitoria del crecimiento que ejercen bacterias aerobias formadoras de endosporas (BAFE) sobre hongos fitopatógenos aislados de plantas ornamentales. La actividad biocida se determinó mediante la coinoculación de los hongos y los aislados bacterianos en placas Petri con agar papa dextrosa Biocen. Se presentan las curvas de inhibición del crecimiento para cada hongo y el control, y se calculó el porcentaje de inhibición del crecimiento radial (PICR). El 62% de los aislados bacterianos mostró la formación de una zona de inhibición del crecimiento de los hongos, y se seleccionaron cinco con actividad inhibitoria simultánea, la cual se evidencia a partir del tercer día de incubación. En las colonias de C. lunata se observó una zona de lisis interna y un engrosamiento del borde en la zona de inhibición. El PICR osciló entre el 51,6 y el 72,2%. La descripción de los aislados bacterianos basada en caracteres fenotípicos confirmó su ubicación taxonómica en el grupo de las bacterias aerobias formadoras de endosporas, Clase Bacilli