Evaluación de la fitotoxicidad de un extracto acuoso del alga Padina gymnospora (Kützing) sobre semillas de Lactuca sativa L.

Padina gymnospora (Kützing) is an algae with pharmacological and biostimulant potentials. The objective of this investigation was to evaluate the phytotoxicity of an aqueous extract of P. gymnospora by means of a bioassay with seeds of Lactuca sativa L. The biomass of P. gymnospora was collected in the eastern zone of the coast of Santiago de Cuba, Cuba. Phytochemical screening of the extract was carried out and the main families of secondary metabolites present in it were determined. The polyphenols were quantified by the Folin-Ciocalteu method. The phytotoxicity bioassay was carried out in vitro, with a duration of 120 hours. Two concentrations of the extract were analyzed: pure extract (P-100) and a 50% dilution (P-50). The negative control was distilled water. The influence of both concentrations on the percentage of relative germination (PGR), the percentage of relative radicle growth (CRR) was evaluated and with these two parameters the germination index (GI) was calculated. In addition, the length of the hypocotyl was measured. A total of six families of secondary metabolites were identified. The most abundant were phenolic compounds and / or tannins and carbohydrates. The concentration of polyphenols was estimated at 0.384 mg g-1 in tannic acid equivalents. The two concentrations of the extract produced more than 95% germination of the seeds. The CRR values were 45.77% for P-100 and 47.15% for P-50, which indicated inhibition of root length. The IG was 46.57% and 45.49% for P-100 and P-50, respectively. The length of the hypocotyl in both treatments exceeded the control. The extract was classified as slightly toxic for the biomodel used. Keywords: phytochemical screening, phytotoxicity, seaweed, secondary metabolites Padina gymnospora (Kützing), es una alga con potencialidades farmacológicas y bioestimulantes. El objetivo de esta investigación fue evaluar la fitotoxicidad de un extracto acuoso de P. gymnospora mediante un bioensayo con semillas de Lactuca sativa L. La biomasa de P. gymnospora se colectó en la zona Este del litoral de Santiago de Cuba, Cuba. Se realizó tamizaje fitoquímico del extracto y se determinaron las principales familias de metabolitos secundarios presentes en él. Se cuantificaron los polifenoles por el método de Folin-Ciocalteu. El bioensayo de fitotoxicidad se realizó in vitro, con una duración de 120 horas. Se analizaron dos concentraciones del extracto: extracto puro (P-100) y una dilución al 50% (P-50). El control negativo fue agua destilada. Se evaluó la influencia de ambas concentraciones sobre el porcentaje de germinación relativo (PGR), el porcentaje de crecimiento de radícula relativo (CRR) y con estos dos parámetros se calculó el índice de germinación (IG). Además, se midió la longitud del hipocótilo. Se identificaron un total de seis familias de metabolitos secundarios. Los más abundantes fueron los compuestos fenólicos y/o taninos y los carbohidratos. La concentración de polifenoles fue estimada en 0.384 mg g-1 en equivalentes de ácido tánico. Las dos concentraciones del extracto produjeron más del 95% de germinación de las semillas. Los valores de CRR fueron de 45.77% para P-100 y 47.15% para P-50 lo que indicó inhibición de la longitud radicular. El IG fue de 46.57% y 45.49% para P-100 y P-50, respectivamente.  La longitud del hipocótilo en ambos tratamientos superó al control. El extracto se clasificó de como levemente tóxico para el biomodelo empleado. Palabras clave: análisis fitoquímico, metabolitos secundarios, fitotoxicidad, algas marina

In vitro antimicrobial activity of total extracts of the leaves of Petiveria alliacea L. (Anamu)

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.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

ANÁLISIS FITOQUÍMICO PRELIMINAR DE DOS EXTRACTOS DEL ALGA Padina gymnospora/ PRELIMINARY PHYTOCHEMICAL ANALYSIS OF TWO EXTRACTS OF Padina gymnospora ALGAE

El estudio de las características fi toquímicas de las algas marinas, ha posibilitado que se justifi quen muchas de las propiedades que poseen estos organismos desde el punto de vista farmacológico. En este trabajo se realizó la detección cualitativa de familias de metabolitos de importancia médico-farmacéutica, en extractos del alga parda Padina gymnospora. La biomasa del alga fue colectada en temporada de seca. A partir de ella se elaboraron dos extractos, uno acuoso y otro hidroalcohólico al 50%. La identifi cación de los metabolitos se realizó por medio de ensayos cualitativos y se cuantificó espectrofotométricamente el contenido de polifenoles totales por Folin Ciocalteu. Se determinó la presencia de 6 familias (cumarinas, fenoles y/o taninos, flavonoides, terpenos y esteroides, saponinas, carbohidratos y/o glucósidos). El contenido de polifenoles fue de 0.384 mg/g de extracto en equivalentes de ácido tánico, en el extracto acuoso, mientras que en el hidroalcohólico el valor fue de 0.329 mg/g. Los grupos de metabolitos que más abundaron en el extracto acuoso fueron los carbohidratos/glucósidos, fenoles/taninos y saponinas, en el hidroalcohólico las cumarinas. Los resultados obtenidos pueden ser de gran interés para la obtención, a partir del extracto acuoso de Padina gymnospora, de taninos, carbohidratos y saponinas. ABSTRACT The phytochemical study of seaweed has made possible the justifi cation of pharmacological properties found in these organisms. The aim in this work was the identifi cation of secondary metabolites families with pharmaceutical and medical importance in Padina gymnospora brown seaweed. The sample was collected in dry season. Two extracts were analyzed: hydroalcoholic (50%) and aqueous. The identifi cation of the metabolites was performed by qualitative essays and total polyphenols were quantifi ed by Folin-Ciocalteau. The presence of 6 families was determined (coumarins, phenols and tannins, fl avonoids, terpenes and steroids, saponins, carbohydrates and glucosides). The phenol content in the aqueous extract was 0.384 mg/g, while in the hydroalcoholic was 0.329 mg/g, measured espectrophotometrically at 675 nm. The aqueous extract of Padina gymnospora exhibited more levels of tannins, carbohydrates and saponins in comparation with hydroalcoholic extract. In general terms, the aqueous extract of P. gymnospora could be considered as more effi cient compared to hydroalcoholic extract in the extraction of tannins, carbohydrates and saponin

In vitro antimicrobial activity of total extracts of the leaves of Petiveria alliacea L. (Anamu)

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