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Los organismos marinos producen metabolitos secundarios bioactivos y son fuentes para la obtención de nuevos bioproductos de uso humano. Sin embargo, estos compuestos pudieran representar un riesgo para el hombre, por lo que resulta imprescindible realizar estudios que permitan descartar aquellos con efectos perjudiciales. En el presente trabajo, se evaluó el potencial de toxicidad in vitro de dos extractos secos (M1061 y M1063), obtenidos a partir de las cepas bacterianas del grupo de actinomicetos CBM-1061 y CBM-1063, aisladas de sedimentos de manglar de la península de Guanahacabibes, Cuba. Para ello, se evaluó el potencial citotóxico de los extractos en diferentes líneas celulares: MDCK, J774 (células derivadas de tejidos sanos) y CT26, 4T1, MCF-7 (de origen tumoral), mediante el ensayo de reducción de bromuro de dimetiltiazol-difeniltetrazolio (MTT) y en el modelo bacteriano Caulobacter crescentus a través del ensayo de sobrevivencia bacteriana. Se evaluaron, también, los posibles efectos sobre el material genético en C. crescentus (Ensayo SOS colorimétrico y resistencia a Rifampicina). Los extractos no fueron tóxicos en el rango de concentraciones evaluadas (1-2000 µg/mL) en C. crescentus ni en las líneas celulares hasta 1000 µg/mL después de 48 h de exposición. Tampoco resultaron genotóxicos (50-2000 µg/mL) ni mutagénicos (50-1000 µg/mL) en C. crescentus. Los resultados obtenidos muestran la no toxicidad de los extractos M1061 y M1063 bajo las condiciones de ensayo. Recibido: 05.07.2022 Aceptado: 20.02.2023 Editor: Georgina Espinosa

La cepa Streptomyces sp. RL8 fue caracterizada en base a su actividad antagónica frente a hongos fitopatógenos, solubilización de fosfatos, producción de sideróforos, y su efecto en la germinación y crecimiento inicial in vitro de frijol Tépari (Phaseolus acutifolius Gray), bajo condiciones controladas. Se aplicó un diseño experimental completamente al azar con un tratamiento bacteriano basado en RL8 (T) y agua destilada como tratamiento Control (C), con cuatro réplicas por tratamiento y 10 semillas por réplica. Las variables de respuesta estudiadas fueron el porcentaje y tasa de germinación (PG y TG), longitud de tallo y de raíz (LT y LR), biomasa fresca y seca de parte aérea (BFPA y BSPA) y biomasa fresca y seca de raíz (BFR y BSR). RL8 mostró actividad antagónica frente a cuatro fitopatógenos de los cinco evaluados, promovió la producción de sideróforos y la solubilización de fosfatos. A escala experimental se observaron diferencias significativas con respecto al grupo control en PG (65.83 vs 30%), TG (4.16 vs 2.25), LT (3.81 vs 1.65 cm) y LR (5.61 vs 2.13 cm), BFPA (2736.75 vs 18.46.75 mg), BSPA (608.75 vs 361.5 mg), BFR (347.0 vs 115.75 mg) y BSR (101.25 vs 58.25 mg). Estos resultados confirman un efecto positivo de RL8 en la germinación y crecimiento inicial de Phaseolus acutifolius Gray, revelando su potencialidad para ser utilizada en su cultivo orgánico o tradicional. Se sugiere su aplicación a escala piloto y su evaluación como alternativa de producción agroecológica en invernadero y en campo.

Marine organisms produce bioactive secondary metabolites andare sources for obtaining new bioproducts for human use. However, they can represent a risk for man, so it is essential to carry out studies to rule out those with harmful effects. In the present work, the in vitro toxicity potential of two dry extracts (M1061 and M1063) obtained from the bacterial strains of the actinomycetes, CBM-1061 and CBM-1063, isolated from mangrove sediments of the Guanahacabibes peninsula, Cuba, was evaluated. For it, the cytotoxic potential of the extracts was evaluated in different cell lines: MDCK, J774 (from health tissues) and CT26, 4T1, MCF-7 (tumor cells) by using dimethylthiazol diphenyltetrazolium bromide (MTT) reduction assay and the Caulobacter crescentus bacterial model through the bacterial survival test. The possible effects on the genetic material in C. crescentus were also evaluated (SOS colorimetric test and resistance to Rifampicin). The extracts were not toxic in the range of concentrations evaluated (1-2000 µg/mL) in C. crescentus, neither in the cell lines up to 1000 µg/mL after 48 hours of exposure. They were no genotoxic (50-2000 µg/mL) normutagenic (50-1000 µg/mL) in C. crescentus. The results obtained show the non-toxicity of M1061 and M1063 extracts under the experimental conditions. [ABSTRACT FROM AUTHOR]

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El objetivo de la presente investigación fue caracterizar microbiológicamente seis biopreparados que se producen en la de Granja Agrobiológica Sol Vida en Pamplona a los que se les atribuyen efectos biofertilizantes, bioestimulantes y antagonistas. La investigación se desarrolló en los laboratorios de microbiología y bacteriología de la Facultad de Ciencias Básicas de la Universidad de Pamplona, de marzo a junio del 2017. Se trabajó en la caracterización de los fundamentales grupos de microrganismos en los seis biopreparados. Se realizaron siembras el medio de Martin para el conteo de hongos, para bacterias y actinobacterias el medio de Bunt y Rovira, para bacterias solubilizadoras de fosfato el medio Pykoskaia y para bacterias de la familia Bacillaceae el medio Mossel modificado. El conteo de colonias de cada microorganismo por biopreparado mostró variaciones notables, así como entre los grupos de microrganismos dentro de cada biopreparado lo que dependió de los ingredientes y del proceso fermentativo. Los seis biopreparados estudiados poseen microorganismos que pudieran tener efecto como bioestimulantes, solubilizadores de fosfatos y antagonistas, aunque las concentraciones son relativamente bajas, ya que solo cuatro alcanzan 106 UFC por ml de microorganismos totales. Los biopreparados presentan diferencias estadísticas en cuanto a la concentración de los diferentes grupos de microorganismos lo que obliga a realizar ensayos de laboratorio y campo para verificar y diferenciar los posibles efectos que pudieran promover en los sistemas de cultivo.

Background: Microorganisms play a fundamental role in soil dynamics of agroecosystems. Objective: To determine soil quality parameters and the abundance of functional groups of edaphic microorganisms in eight different contrasting sites evaluated in a milpa agroecosystem interclassed whit fruit trees (MIAF) and in monocultures system. Methodology: Bulk density, humidity, pH, electrical conductivity, percentage of ash, oxidizable organic matter, oxidizable carbon, total nitrogen, inorganic nitrogen and nutrients (NO3-, Na+, Ca2+ and K+) were determined in composite soil samples by triplicate for each sites, as well as the diversity of weeds and abundance of total actinomycetes, nitrogen-fixing actinomycetes, yeasts, fungi, bacteria, and arbuscular mycorrhizal fungal spores. A principal component analysis was carried out to calculate a soil quality index (SQI). Analysis of variance, Tukey's mean comparison test (P ≤ 0.05), linear correlation, cluster analysis and canonical correlation were performed. Results: A greater amount of total actinomycetes (> 4 Log CFU g-1 soil) and nitrogen-fixing actinomycetes (> 3.8 Log CFU g-1 soil) and fungi (> 1.7 Log CFU g-1 soil) were observed in the MIAF system compared to the monocultures. For the sites with corn-bean association in the MIAF system, a high positive correlation was observed between organic matter content and nitrogen-fixing actinomycetes (r = 0.60) and yeasts (r = 0.73), as well as with the percentage of total nitrogen with yeasts (r = 0.70) and nitrogen-fixing actinomycetes (r = 0.75). Implications: The methodology used allowed the grouping of the sites studied, based on the SQI and a reduced set of variables. Conclusion: The MIAF system favored the abundance of functional groups, soil quality parameters and the availability of nutrients in the soil compared to the monoculture sites.

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Popularly known as guarana, Paullinia cupana Kunth var. sorbilis (Mart.) Ducke, from the Paullinieae tribe, Sapindaceae family, is a native Brazilian species of considerable economic importance in the pharmaceutical and food industry. Actinomycetes are qualitatively and quantitatively important in the rhizosphere, being able to influence plant growth and protect the roots from the invasion of pathogenic fungi, thus being able to be used in the biological control of diseases in plantations. This work aimed to evaluate the antibacterial action of rhizospheric actinomycetes from guaranazeiro from plantations located in the municipality of Maués/AM, in order to find new antimicrobial agents against pathogenic bacteria in humans. 17 actinomycetes isolated from the guaranazeiro rhizosphere were investigated and evaluated for their antimicrobial activity against four pathogenic bacteria of clinical interest. Staphylococcus aureus, Streptococcus pneumococcus, Enterococcus faecalis and Bacilus subtilis. The evaluation of antagonistic activity by the isolates was performed using the cross streak and thermostability method. The results revealed that the ACT 4 isolate enabled the inhibition of only two pathogens, Staphylococcus aureus and Bacillus subtilis, while the ACT 93 isolate exhibited a broad spectrum of activity against all the gram-positive pathogenic bacteria evaluated. As for thermostability and production of metabolites by the isolates, only the ACT 4 isolate was able to inhibit an Enterococcus faecalis bacterium. This study shows that actinomycete isolates have the potential to act as potential sources of new antibacterial compounds against human pathogenic microorganisms. However, more in-depth testing is needed so that an important entry into the pharmaceutical industry can take place in the future. [ABSTRACT FROM AUTHOR]

Actinomycetes are a diverse bacterial group responsible for several diseases, such as tuberculosis, mycetoma, nocardiosis, allergic pneumonia, actinomycosis, erythrasma, plantar axillary trichomycosis and dermatitis, among others. The knowledge of the chemical composition of the various microbial structures and the biological activity they trigger is decisive to know its origin and pathogenic aspects. Therefore, the magnitude of the damage caused by these bacteria is the consequence of their recognition and response to these pathogenicity factors, as well as by the host's resistance mechanisms. In addition to the great induction capacity of biological processes associated with their structural components, actinomycetes have developed various strategies that are associated with their virulence, such as: survival in phagocytic cells, deviation of apoptotic mechanisms towards necrosis cell, biofilm formation, release of extracellular vesicles, induction of extracellular traps, release of enzymes and release of toxins. This paper presents some evidence that allows us to understand the host-parasite relationship and that in the future can be considered possible therapeutic targets for the design of new strategies in the treatment of these infections. [ABSTRACT FROM AUTHOR]

Plant growth-promoting bacteria (PGPB) are a tool that helps to have clean and sustainable agriculture as well as in the reduction of agrochemicals. 35 Actinomycetes were isolated from soil samples from vine, Ica crops. These 35 strains were characterized by their enzymatic ability to degrade different substrates such as oats, lecithin, starch, casein, tween 81 and carboxymethylcellulose. 18 actinobacteria strains were selected that had the best antagonistic response against Aspergillus sp. after being evaluated by bilayer technique in different culture media such as nutrient agar, plate count agar, potato dextrose agar and a new culture medium called ASMICO. To verify the PGPB capacity, phosphates solubilization, nitrogen fixation, siderophore production and acetic indole acid (AIA) production were qualitatively evaluated. 4 actinomycetes were selected with the best antagonism and with at least one of the PGPB characteristics. They then clashed against the phytopathogen Phytophthora cinnamomi which reduced their growth to 10 mm compared to 49 mm of negative control. Using ANOVA with the Statistica 10 software it was confirmed that the new ASMICO culture medium has the greatest effect and is significantly (p <0.05) different compared to the 3 other media used. It is concluded that actinomycetes isolated from Vine crops soils are a potential source to be used as producers of antifungal metabolites as well as PGPB. [ABSTRACT FROM AUTHOR]

As well as their complex life cycle and industrial importance, Streptomyces spp. are also remarkable due to the accessory genetic elements they harbour. Integrative elements, which have only been found in actinobacteria, are present as integrated chromosomal copies. [ABSTRACT FROM AUTHOR]

Los hongos y actinomicetos asociados a infecciones en humanos, se encuentran ampliamente distribuidos en la naturaleza. El suelo y las plantas son el hábitat de numerosos hongos y bacterias. Los campesinos son altamente vulnerables a sufrir heridas y pueden contaminarse con estos microorganismos. Con la finalidad de conocer el número de colonias de los agentes causantes de micosis subcutáneas humanas a partir de la naturaleza, se realizó el aislamiento de los microorganismos respectivos a partir de suelo y plantas en 11 municipios del estado de Puebla. De cada municipio se colectaron 50 muestras, cada una consistió de 10 g de suelo y 10 g de hojas de la planta más cercana; se prepararon suspensiones respectivas, las cuales fueron inoculadas en agar dextrosa Sabouraud, incubadas a 28 ºC, y revisadas periódicamente para identificar los microorganismos de interés con base en su morfología. De 110 muestras procesadas, se obtuvieron 441 aislados, de los cuales 281 fueron hongos (133 de suelo y 148 de plantas) y 160 actinomicetos (96 de suelo y 64 plantas). Los hongos aislados fueron identificados por su morfología macroscópica y microscópica. Los actinomicetos fueron identificados por su morfología macroscópica (colonial) y microscópica, y por pruebas bioquímicas. En mayor proporción se aislaron agentes potenciales de cromoblastomicosis (Fonsecaea pedrosoi y Cladophialophora carrionii), seguidos del agente de esporotricosis (Sporothrix schenckii) y de los agentes de actinomicetoma (Nocardia brasiliensis y N. otitidis-caviarum). Del suelo de Cholula y de plantas de Tecali de Herrera, se obtuvieron el mayor número de aislados fúngicos. Del suelo de Chignahuapan y de plantas de Izúcar de Matamoros se obtuvo el mayor número de aislados de actinomicetos. En este estudio se encontraron, tanto en suelo como en plantas de 11 municipios del estado de Puebla, un alto número de colonias de hongos y actinomicetos causantes de infecciones subcutáneas en humanos, y en una proporción similar a la frecuencia con que las patologías respectivas son reportadas en la literatura mexicana.

BACKGROUND: Mycetoma is an infectious, granulomatous, chronic disease that affects the skin, subcutaneous cellular tissue and bone. It is caused by filamentous bacteria (actinomycetoma) and fungi (eumycetoma). In Mexico, the most frequent causative agent of actinomycetoma is Nocardia brasiliensis, followed by Actinomadura madurae. OBJECTIVE: To evaluate the expression of mannose (MRC1) and complement (CR3) receptors in human neutrophils infected with N. brasiliensis and A. madurae. MATERIAL AND METHOD: An experimental study performed from June to December 2017 was done in which human neutrophils from peripheral blood were infected with N. brasiliensis and A. madurae, the kinetics were followed post infection of 1, 2, 3, 4 and 5 hours. The total RNA was obtained for its subsequent retro-transcription, the quantification of the genes of the receptors was carried out by qPCR and the expression at the protein level was corroborated by confocal microscopy. RESULTS: In human neutrophils infected with N. brasiliensis and A. madurae, a high expression of the MRC1 receptor was detected which was increased from the first hours of infection with both strains, with respect to the CR3 receptor, we found that the neutrophils expressed a discreet way in early times of infection. CONCLUSION: Neutrophils infected with N. brasiliensis and A. madurae on express the mannose receptor MRC1; however, the levels of expression of complement receptor CR3 are low. [ABSTRACT FROM AUTHOR]

Actinomicetos são um dos principais produtores de enzimas, vitaminas e metabólitos secundários, destacando-se o gênero Streptomyces, o qual tem uma ampla capacidade de produção de antibióticos eficazes no combate a diferentes microrganismos, entre eles o Staphylococcus sp. Em virtude dessa eficiência no combate a patógenos, o objetivo deste trabalho foi avaliar a produção de metabólitos com atividade antimicrobiana produzidos por 67 Streptomyces isolados de liquens da região amazônica, ante isolados de mastite caprina (Staphylococcus aureus) do estado de Pernambuco, Brasil. Foi utilizado um planejamento fatorial para avaliar a influência das fontes de carbono (glicose) 0%, 0,5% e 1% e de nitrogênio (farinha de soja) 1%, 2,5% e 4% na produção dos antimicrobianos, bem como das variáveis pH, biomassa e atividade antimicrobiana. Dos Streptomyces estudados, o DPUA 1566 foi o que se destacou por formação de halos de inibição entre 18 e 26mm ante os isolados de mastite caprina. Foi possível verificar que a fonte de carbono inibiu a produção de antimicrobianos quando submetidos a uma concentração de glicose de 1%; com a retirada desta, os Streptomyces apresentaram uma elevada capacidade de produção de metabólitos com atividade antimicrobiana tendo potencial para o tratamento de mastite caprina.

Existen microorganismos benéficos a las plantas que se emplean de manera específica y aislada para favorecer la germinación y crecimiento. El beneficio es mayor si, en lugar de inocular un microorganismo específico al sustrato, se inoculan grupos de éstos para que disminuyan la incidencia de las enfermedades inducidas por fitopatógenos de la raíz; y, a su vez, favorezcan la emergencia y crecimiento de los cultivos. El objetivo de este trabajo, con enfoque holístico, fue evaluar las variables emergencia y altura de plántulas en almácigo, e incidencia en el invernadero al reintroducir antagonistas a Phytophthora capsici en grupos de 8, 16, 24 y 32 aislamientos de microorganismos, en los sustratos de germinación del chile (Capsicum annuum) y frijol terciopelo (Mucuna deeringiana). Los tratamientos con grupos de antagonistas presentaron al menos uno de los efectos benéficos esperados (en comparación con el testigo), al incrementar la emergencia, la mayor altura de plántulas en el almácigo, y la menor incidencia por P. capsici en el invernadero. Los tratamientos que presentaron la mayor altura de plántulas en almácigo, fueron los tratamientos con grupos de 18, 24 y 32 antagonistas, que incluyeron el grupo de ocho actinomicetos. El mejor tratamiento fue con ocho aislamientos de actinomicetos, que presentó la mayor emergencia de plántulas para ambos cultivos en el almácigo y la menor incidencia de P. capsici en el cultivo de chile en invernadero.

Introdução: As bactérias são seres essenciais e inseparáveis da vida na terra, algumas inofensivas e até benéficas para o seu hospedeiro, sendo intrinsecamente ligadas aos comportamentos desses organismos, assim habitando diversos ambientes. Dentre os microrganismos que compõem esse domínio, os actinomicetos, mais especificamente do gênero Streptomyces spp., são provenientes, principalmente, do solo, considerado ambiente propício ao seu desenvolvimento e apresentam capacidade de sintetizar os metabólitos secundários, como os antibióticos e enzimas extracelulares, ambos com atividade antibacteriana, antifúngica e antiprotozoária, as quais podem ter fatores interferentes em relação ao seu desempenho. Objetivo: Propusemo-nos a avaliar o impacto do manejo de lavouras cafeeiras convencionais e orgânicas na diversidade do solo e no potencial antimicrobiano dos actinomicetos. Método: Amostras de solo em uma área específica dos cultivos cafeeiros foram coletadas e submetidas à diluição seriada em solução salina 0,9%, semeada em meio de cultura sólido, através da metodologia Pour Plate e incubados à temperatura ambiente. A partir das colônias obtidas realizou-se análises macro e microscópicas para caracterização do grupamento microbiano. As colônias de actinomicetos foram isoladas e posteriormente inoculados frente a outros microrganismos oportunistas e ou patogênicos em meio Ágar Mueller-Hinton, com o intuito de observar a performance inibitória dos actinomicetos em relação ao crescimento dessas espécies confrontadas. Resultados: Foram isoladas 7 colônias de actinomicetos na amostra orgânica e 6 colônias de actinomicetos na amostra convencional, no qual em análise microscópica, 9 cepas apresentaram hifas filamentosas ou fragmentavam-se em bacilos. Em relação aos isolados do solo orgânico, houve inibição de crescimento por 3 cepas para Streptococcus pyogenes, 5 cepas para Candida albicans, 3 cepas para Candida krusei enquanto que para Staphylococcus aureus não houve nenhuma cepa isolada que demonstrou inibição de crescimento. Já os isolados do solo convencional, ocorreu inibição somente do crescimento de Candida krusei por 2 cepas. Conclusão: O manejo orgânico não apresentou número expressivo de isolamento se comparado ao manejo convencional, porém apresentou maior inibição de crescimento frente aos microrganismos de interesse de estudo em infecções hospitalares em relação aos microrganismos isolados do manejo convencional. [ABSTRACT FROM AUTHOR]

One hundred and forty five cellulolytic thermophilic actinomycete strains were isolated from 71 compost, soil, hay and dung samples. Streptomyces sp. (50,63%), Thermomonospora curvata (15,82%), T. chromogena (13,92%), and other species were identified. Endoglucanase, exoglucanase and β-glucosidase activities were evaluated from 10 cellulolytic actinomycete strains. Among these the Streptomyces sp. 7CMC10 strain showed the biggest activity levels corresponding to 20,14; 2,61 and 5,40 UI/mg of protein, respectively.

The aquaculture has reached a new age, in which traditional extensive systems are being substituted by technology-intensive aquaculture systems. In order to achieve higher yields, aspects of fish quality have been neglected, a fact that causes or aggravates hitherto tolerable problems, such as off-flavor. The main purpose of this review is to clarify, briefly, the problem of off-flavor in aquaculture, as well as put forward present solutions and future perspectives. A aquicultura entra numa nova era nas últimas décadas, em que os sistemas extensivos tradicionais estão sendo substituídos por criações intensivas e tecnificadas. No intuito de auferir maior lucratividade, a qualidade do pescado tem sido relegada a segundo plano, fato que gera ou agrava problemas antes toleráveis, a exemplo do off-flavor. Assim, a presente revisão tem por objetivo esclarecer, de forma sucinta, o problema do off-flavor na aquicultura, bem como apontar as soluções atuais e as perspectivas futuras para reverter a situação que se apresenta.

Los polihidroxialcanoatos (PHA) son polímetros considerados como fuente de materiales biorenovables, biode- gradables y plásticos con amplios usos industriales, pero los altos costos de producción detienen su aplicación a gran escala. En el presente trabajo, fueron aisladas 10 cepas de Actinomicetos de 60 muestras de suelo rizosférico proveniente de diferentes zonas de la región de Boyacá, Colombia. Observaciones preliminares utilizando el colorante azul de Nilo permitio identificar en tres cepas la presencia de gránulos intracelulares fluorescentes del tipo PHA. Las tres cepas fueron cultivadas en dos medios para obtener cantidades signifi- cativas de PHA, encontrándose que la cepa 7F era la que presentaba una producción importante. Después de la purificación, cuantificación e identificación se determino un rendimiento del 27,48% en peso seco, lo que significa una buena productividad. Mediante pruebas bioquímicas y análisis molecular la cepa 7F fue identifi- cada como Streptomyces subrutilus.

El objetivo de esta investigación consistió en comparar la flora microbiana a partir de la metodología convencional implementada en Garagoa, Boyacá, para el tratamiento de residuos sólidos domiciliarios con una metodología experimental que consistió en humectar los residuos con agua en lugar de lixiviado, y no mezclar el material por tratar con otro de distintos tiempos de compostaje; para tal fin, se caracterizaron y determinaron los tamaños poblacionales de heterótrofas totales, pseudomonas, hongos y actinomicetos a partir de muestras tomadas en distintas etapas del proceso. De las distintas muestras analizadas se identificaron hongos de los géneros Cladosporium y Aspergillus, propios del proceso de compostaje, Fusarium, Scopulariopsis, Moniliella, Curvularia y levaduras del género Rhodothorula.En el agar ISP2 (para el aislamiento de actinomicetos) se identificaron diversos morfotipos: bacilos esporulados, bacilos gramnegativos, cocobacilos, cocos grampositivos y una bacteria del género Streptomyces. De acuerdo con los resultados de los tamaños poblacionales de los grupos de microorganismos estudiados no se presentaron diferencias significativas entre los tratamientos evaluados; sin embargo, el mayor promedio de los recuentos se presentó en el tratamiento experimental. Palabras clave: materia orgánica; bacterias; hongos; actinomicetos; compost. Abstract This research was aimed at comparing microorganisms from conventional household solid waste treatment in Garagoa, Boyacá, using an experimental methodology consisting of moistening waste with water instead of lixiviate and not mixing the material to be treated with other material having different composting times (i.e. organic fertilizer). Complete heterotopous, pseudomona, fungi and actinomycete population size were thus characterised from samples taken from different stages of the process. Fungi from the Cladosporium and Aspergillus genera (from composting) were identified from this analysis, as well as Fusarium, Scopulariopsis, Moniliella, Curvularia and yeasts from the Rhodothorula genera. Some morphotypes were identified in the ISP2 agar (for the actinomycete isolate): sporulated bacilli, gram-negative bacilli, cocobacilli, gram-positive coci and one bacterium from the Streptomyces genus. According to the results regarding the population sizes of the microorganism groups studied, no meaningful differences were presented between the treatments being tested; however, the experimental treatment presented the highest average count. Key words: organic material, bacteria, fungi, actinomycete, organic

Los actinomicetos son importantes en la sostenibilidad de sistemas naturales. Su diversidad fue evaluada en suelos de bosque, pastizal y rastrojo, y dos profundidades en el Sur del Trapecio Amazónico Colombiano. Se analizaron suelos de cinco repeticiones por cobertura para un total de 15 unidades. Se tomaron seis muestras en cada unidad y dos profundidades, para un total de 30. Los actinomicetos cultivables se determinaron por recuento en placa, se extrajo ADN, se amplificó el gen ADNr 16s y su diversidad genética se estimó por ARDRA. Hubo diferencias de abundancia entre coberturas y profundidades, relacionadas con la vegetación, presencia de lombrices, macrofauna, altos niveles de materia orgánica, y bases totales. Se obtuvieron valores de diversidad fenotípica similares para las tres coberturas, pero los bosques son más diversos. Se identificaron 16 morfotipos, agrupados en séis géneros, siendo Streptomyces el más abundante. La heterogeneidad de los patrones ARDRA no permitió la asignación de especies, reflejándose variaciones en las secuencias de diferentes operones ADNr 16s en un mismo organismo. Las perturbaciones en la cobertura influyen sobre los actinomicetos, generando cambios en su abundancia y diversidad. Su importancia ecológica permite proponerlos como indicadores biológicos de alteración del paisaje.Communities of Actynomicetes fungy in three vegetation types of the Colombian Amazon: abundance, morphotypes and the 16s rDNA gene. Among soil microorganisms, Actinomycetes play an important role in the sustainability of natural and agricultural systems: decomposition of organic matter; degradation of recalcitrant compounds like lignin; nitrogen fixation; degradation of agricultural chemicals and biological control in plants and animals. We evaluated their diversity in soils under three different vegetation covers (pasture, tropical primary forest and stubble) at two depths in the Southern Colombian Amazon border. We collected five replicates per vegetation type (in each, three samples at 0-20cm and three at 20-30cm; for a total of 30 samples). Abundance and phenotypic diversity were determined by plate counting. Genomic DNA was extracted from the isolates: the 16s rDNA gene was amplified with specific primers, and its genetic diversity was estimated by means of an amplified restriction analysis (ARDRA). Actynomicetes abundance varied with vegetation and depth, possibly reflecting presence of earthworms, macro-fauna and physico-chemical characteristics associated to fertility, as well as organic matter, total bases, and optimal capacity to cationic interchange. Primary forests had the highest diversity. Sixteen morpho-types (six genera) were identified; Streptomyces was the most abundant everywhere. The heterogeneity of ARDRA patterns prevented species identification because of the intra-species variability in sequences of 16s rDNA operons. This community is a biological indicator of landscape alteration and could include new bio-active compounds of pharmaceutical interest. Rev. Biol. Trop. 57 (4): 1119-1139. Epub 2009 December 01.

This research aimed to evaluate the secondary effects of secondary metabolites produced by streptomycetes on spore germination and mycelial growth of the phytopathogenic fungi Cladosporium fulvum Cooke and Fusarium oxysporium f. sp. lycopersici from tomato plants. Metabolites produced by streptomycete isolates codified as AC-147 and AC-92 caused 94.1% inhibition of C. fulvum while AC-95 isolate caused 33.9% inhibition. AC-92 was the most efficient for F. oxysporum f. sp. lycopersici, causing 94.2% inhibition of spore germination. For mycelial growth, AC-26 and AC-92 were the most efficient in inhibiting C. fulvum growth by 46.6% and F. oxysporum f. sp. lycopersici by 29.9%. These streptomycetes are potential agents for biocontrol development methods of these tomato plant pathogenic fungi.Este trabalho teve como objetivo avaliar o efeito de metabólitos secundários produzidos por estreptomicetos na germinação de esporos e no crescimento micelial dos fungos Cladosporium fulvum Cooke e Fusarium oxysporum sp. f. lycopersici da cultura do tomateiro. Metabólitos produzidos pelos isolados AC-147 e AC-92 causaram 94,1% de inibição da germinação de esporos de C. fluvum, enquanto que o isolado AC-95 causou 33,9% de inibição. O AC-92 foi o mais eficiente para F. oxysporum f. sp. lycopersici, causando 94,2% de inibição na germinação de esporos. Para o crescimento micelial, AC-26 e AC-92 foram os mais eficientes na inibição dos fungos C. fulvum, em 46,6%, e F. oxysporum f. sp. Lycopersici, em 29,9%. Esses estreptomicetos são potenciais agentes para o desenvolvimento de métodos de controle biológico desses fungos fitopatogênicos do tomateiro.

The objective of this study was to examine the alkalithermophilic actinomycete communities in the subtropical environment of Jujuy, Argentina, characterized by sugarcane crops. Laceyella putida, Laceyella sacchari, Thermoactinomyces intermedius, Thermoactinomyces vulgaris and Thermoflavimicrobium dichotomicum were isolated on the media with novobiocin, from sugar cane plants and renewal rhizospheres, and grass and wood soils. Soil pH was almost neutral or lightly alkaline, except for grass soil acidified by lactic liquor. A smaller number of actinomycetes was found on the living plants and bagasse (recently obtained or stored according to the Ritter method) with respect to decomposed leaves on the soil. Thermophilic species of Laceyella, Thermoactinomyces, Thermoflavimicrobium, Saccharomonospora, Streptomyces and Thermononospora were isolated on the media without novobiocin, from composted sugar cane residues. Air captured near composted bagasse piles, contained alkalithermophilic actinomycete spores.El objetivo de este trabajo fue examinar los actinomicetos termoalcalófilos presentes en el área subtropical de Jujuy, Argentina, caracterizada por el cultivo de la caña de azúcar. Se aislaron en medio con novobiocina las especies Laceyella putida, Laceyella sacchari, Thermoactinomyces intermedius, Thermoactinomyces vulgaris y Thermoflavimicrobium dichotomicum a partir de la rizósfera de plantas y de renuevos de caña de azúcar, así como de suelos de pastura y de monte natural. El pH de los suelos era casi neutro a ligeramente alcalino, excepto en un solo caso en que el suelo estaba acidificado por licor láctico. El número de actinomicetos encontrados sobre los tejidos vivos y en el bagazo recién obtenido o almacenado según el método de Ritter fue pequeño en comparación con el observado sobre las hojas en descomposición. L. sacchari predominó respecto de T. vulgaris. Se aislaron especies termoalcalófilas de Laceyella, Thermoactinomyces, Thermoflavimicrobium, Saccharomonospora, Streptomyces y Thermononospora de los residuos compostados de caña de azúcar utilizando medio sin novobiocina. El aire capturado cerca de pilas de bagazo en compostaje contenía esporos de estos organismos.

Studies with streptomycetes in biocontrol programs and plant growth promotion are presented as technological alternatives for environmental sustainable production. This work has the objective of characterizing six isolates of streptomycetes aiming the production of extracellular enzymes, indole acetic acid, capacity for phosphate solubilization, root colonization and growth under different pH and salinity levels. For detection of enzyme activity the isolates were grown in culture media with the enzyme substrates as sole carbon source. The root colonization assay was performed on tomato seedlings grown on 0.6% water-agar medium. Growth under different pH and salinity levels was evaluated in AGS medium with 1%, 1.5%, 2%, 2.5%, and 3% NaCl, and pH levels adjusted to 5.0, 5.5, 6.0, 6.5, and 7.0. All isolates produced the enzymes amylase, catalase, and lipase, as well as indole acetic acid. With one exception (AC-92), all isolates presented cellulolytic and chitinolytic activity, and only AC-26 did not show xylanolytic activity. The isolates AC-147, AC-95, and AC-29 were the highest producers of siderophores. The isolates AC-26 and AC-29 did not show capacity for phosphate solubilization. All isolates colonized tomato roots in vitro, and AC-92 grew under all pH and salinity levels tested. The streptomycetes tested were considered as potential biocontrol and plant growth promotion agents.Estudos com estreptomicetos em programas de biocontrole e promoção de crescimento de plantas são alternativas tecnológicas de produção sustentáveis ao ambiente. O presente trabalho teve como objetivo caracterizar seis isolados de estreptomicetos quanto à produção de enzimas extracelulares, ácido indolacético e sideróforos, capacidade de solubilização de fosfatos, colonização radicular e de crescimento em diferentes níveis de pH e salinidade. Para detectar a produção das enzimas extracelulares, os isolados foram cultivados em meio de cultura contendo os substratos dessas enzimas, como única fonte de carbono. Para determinar a capacidade de colonizar o sistema radicular, sementes de tomate foram cultivadas em meio ágar-água 0,6% e inoculadas com os estreptomicetos. O crescimento em diferentes níveis de salinidade e pH foram avaliados em meio de cultura AGS, com os níveis de NaCl 1%, 1,5%, 2%, 2,5% e 3% e níveis de pH ajustados em 5,0, 5,5, 6,0, 6,5 e 7,0. Todos os isolados produziram as enzimas amilase, catalase e lípase, assim como o ácido indolacético. Todos os isolados apresentaram atividade celulolítica e quitinolítica, com exceção do AC-92. Somente o AC-26 não demonstrou atividade xilanolítica. Os isolados AC-147, AC-95 e AC-29 foram os maiores produtores de sideróforos. Os isolados AC-26 e AC-29 não demonstraram a capacidade in vitro de solubilizar fosfatos. Todos os isolados colonizaram as raízes das plântulas de tomateiro e AC-92 apresentou crescimento em todos os índices de salinidade e pH avaliados. Os estreptomicetos testados neste estudo foram considerados potenciais agentes de biocontrole de doenças e promoção do crescimento de plantas.

Actinomycetes are microorganisms widely distributed on the ground and other natural environments due the great interest in producing bioactive compounds and enzymes whit entomopathogenic activity, particularly against Aedes Aegypti. Hydrolytic enzymes such as lipases, proteases, and chitinases are involved in the toxicity and biological control of some insects. Due to this, the ability to produce lipase and to present avermectin gene (aveD) was evaluated in 119 actinomycetes from different localities of the world like as Canada (FW), Africa Desert (SHA), United States (NEV), and Mexico (CHI and MC). Lipase activity was done using rhodamine agar and tween 80, the plates were incubated for 5 days at 30°. In the case of avermectin was detected aveD gen. Of total actinomycetes, 29% were positive for lipase activity, CHI-150 was the most fluorescent. While 39% present AveD gen, wherein the localities of Canada and Mexico (FW and MC) present this gene. These results indicate the possibility of using this microorganism for biological control of Aedes Aegypti and plague insects of high economic impact in agriculture. [ABSTRACT FROM AUTHOR]

Actinomycetes are important plant disease control and growth promotion agents, which makes it necessary to develop technology to produce large quantities of inoculum for green-house and field work. The present study had the objective of evaluating the growth of several isolates of Streptomyces in sterile rice for inoculum production. The sterile rice was inoculated with isolates of S. thermotolerans, S. griseus subsp. griseus, Streptomyces sp. N0035, S. purpurascens, and Streptomyces sp., and incubated at 28 ± 2ºC. Five days after its inoculation, mycelial growth and sporulation was observed for all Streptomyces isolates on the rice grains. Twelve days after incubation, the colonized rice was transferred to envelopes of dark brown paper and let to dry in an incubator at 30ºC for three days. After drying, 1g of colonized rice was added to 200 mL of sterile distilled water and the number of spores was counted under a microscope with a Newbauer counting chamber. Spore production varied from 0.14 × 10(9) to 1.47 × 10(9) spores per gram of rice and differed among the Streptomyces species. Sterile rice can be an alternative substrate for low cost mass production of Streptomyces inoculum.Os actinomicetos são importantes agentes de controle biológico de doenças e promoção de crescimento de plantas, tornando necessária a obtenção de grandes quantidades de inóculo para trabalhos em casa-de-vegetação e campo. No presente trabalho, avaliou-se o crescimento de diversas espécies de Streptomyces em arroz esterilizado para a produção de inoculo. O arroz foi inoculado com isolados de S. thermotolerans, S. griseus subsp. griseus, Streptomyces sp. N0035, S. purpurascens e Streptomyces sp. e incubado a 28 ± 2ºC. Cinco dias após a incubação, para todos os isolados de Streptomyces, o crescimento micelial e esporulação eram visíveis nos grãos de arroz. Doze dias após incubação, o arroz colonizado foi transferido para envelopes de papel pardo e colocado em estufa a 30ºC por três dias. Após secagem, adicionou-se 1 g do arroz em 200 mL de água e fez-se a contagem de esporos por grama de arroz, em câmara de Newbauer. A produção de esporos de Streptomyces sp. variou de 0,14 × 10(9) a 1,47 × 10(9) esporos por grama de arroz e variou entre as espécies de Streptomyces. O arroz esterilizado é um substrato viável para a produção massal, de baixo custo, de inóculo de estreptomicetos.

Frankia are soil microorganisms that form symbiosis with roots of tree species called actinorhizal plants and are capable of fixing atmospheric N2. This study was carried out to characterize morphologically, physiologically and to assess the nodulation of four Frankia reference strains (HFPCcI3, JCT287, KB5 and F59) and 12 (IPRF) isolated from root nodules of Casuarina plants. All strains (Reference and IPRF) were characterized as Gram-positive and 50% as acid-fast. The Frankia strains produced alkali in the culture medium, except the IPRF006, IPRF008 and IPRF010. The colonies of strains F59, IPRF002, IPRF004, IPRF005, and IPRF011 produced melanin. Among reference strains, only JCT287 grew in culture media with pH 5.5, while with pH 6.0 both strains JCT287 and KB5 presented growth. The regression analysis showed a linear relationship (Y = 67.56+ 3.88X and R2=0.5862, p < 0.05) and Pearson’s correlation coefficient (r=0.766, p < 0.05) between number of spores and hyphae (120 to 480 UFC mL-1) and total protein (18 to 145 µg mL-1). It was observed that the strains F59 had a higher proportion of total protein 50.0% than JCT287 with 7.0% and that the IPRF strains showed values between 17.5 and 29.3%. All strains presented ability to produce indolic compounds in growth media with values ranging from 5.9 to 98.8 µM.Frankia são microrganismos capazes de fixar N2 quando em simbiose com espécies arbóreas, denominadas plantas actinorrízicas. Este estudo foi conduzido para caracterizar morfologicamente, fisiologicamente e avaliar a nodulação de quatro estirpes referência de Frankia (HFPCcI3, JCT287, KB5 e F59) e 12 estirpes (IPRF) isoladas de nódulos de Casuarina. Todas as estirpes (Referência e IPRF) foram Gram-positivas e 50% foram “acid-fast”. As estirpes de Frankia alcalinizaram o meio de cultura, exceto IPRF006, IPRF008 e IPRF010. As colônias das estirpes F59, IPRF002, IPRF004, IPRF005 e IPRF011, produziram melanina. Entre as estirpes referência, apenas a JCT287 cresceu no meio de cultura com pH 5,5, enquanto no meio com pH 6,0 as duas, JCT287 e KB5, apresentaram crescimento. A análise de regressão mostrou uma relação linear (Y = 67,56+ 3,88X e R2=0,5862, p < 0,05) e coeficiente de correlação de Pearson (r=0,766, p < 0,05) entre número de esporos e hifas (120 a 480 UFC mL-1) e proteína total (18 a 145 µg mL-1). Foi observado que a estirpe F59 apresentou uma maior proporção de proteína total (50%) do que a JCT287 (7,0%) e, que as estirpes IPRF mostraram valores entre 17,5 e 29,3%. Todas as estirpes produziram compostos indólicos com valores variando de 5,9 a 98,8 µM.

Este trabalho teve como objetivo avaliar o efeito de seis isolados de estreptomicetos na mortalidade e eclosão de juvenis de segundo estádio (J2) de Meloidogyne incognita e no controle da meloidoginose em mudas de tomateiro. Foi montado um bioensaio em placas tipo Elisa, sendo adicionados em cada célula, 200 µL de metabólitos dos isolados, com 20 µL de uma suspensão com 25 juvenis de segundo estádio (J2) de M. incognita. Os metabólitos produzidos por Streptomyces griseus subsp. griseus causaram 98,2% de mortalidade dos J2 de M. incognita. Em outro bioensaio, foram adicionados 3 mL dos metabólitos em frascos de vidro, com 100 µL da suspensão contendo 25 ovos de M.incognita. O isolado N0035 de Streptomyces proporcionou 98,8% de inibição na eclosão de J2 de M. incognita. Num terceiro bioensaio, o substrato de produção de mudas foi infestado com suspensão de estreptomicetos e incubado por 30 dias. Quinze dias depois da germinação das sementes do tomateiro, foi realizada a inoculação com 2.000 J2 por planta. Verificou-se a redução de 68% no número de galhas por grama de raiz e de 76,8% na massa de ovos por grama de raiz, nas mudas produzidas no substrato infestado e incubado com Streptomyces griseus subsp. griseus, quando comparado com a testemunha.This work aimed to evaluate the effect of six streptomycete isolates on mortality, hatching, and control of Meloidogyne incognita on tomato seedlings. An assay was conducted in Elisa plates, with the addition of 200 µL of the streptomycete metabolites, along with 20 µL of suspension containing 25 second stage juveniles (J2) of M. incognita. The metabolites produced by Streptomyces griseus subsp. griseus caused mortality of 98.2% on M. incognita. A second assay was conducted with 3 mL of streptomycete metabolites and 25 eggs of M. incognita. The isolate N0035 of Streptomyces caused inhibition of 98.8% on hatching. In a third assay, potting mix was infested with suspension of the streptomycetes isolates and incubated for 30 days. Fifteen days after germination, tomato seedlings were inoculated with a suspension containing 2,000 J2 of M. incognita. Reductions of 68% in the number of galls per gram of roots and of 76.8% in the egg mass per gram of roots were observed on tomato seedlings grown in the potting mix inoculated with Streptomyces griseus subsp. griseus, compared to the control.

Los metabolitos microbianos ofrecen diversas actividades biológicas. Dos de los más prolíferos grupos productores de metabolitos bioactivos son los actinomicetos y los hongos filamentosos aislados de suelos. Los microorganismos acuáticos han emergido recientemente como una fuente de especies capaces de biosintetizar metabolitos con estructuras novedosas. En este contexto los hongos tropicales se están incorporando a los programas de preselección como potenciales productores de fármacos con nuevos modos de acción.

Este trabalho teve por objetivo avaliar a influência do cultivo da soja sobre a dinâmica da população bacteriana, em dois solos de Cerrado do Estado de São Paulo, originalmente cobertos com Paspalum notatum (em Barretos) e Brachiaria decumbens (em S��o Carlos). Nesses solos, a densidade da população de bactérias em geral variou de 398,1 x 10³ a 467,7 x 10³ e de 123 x 10³ a 218,8 x 10³ ufc (unidades formadoras de colônias)/g de solo seco, respectivamente. O cultivo da soja, em ambos os solos, resultou em incrementos variados nos números de ufc/g de solo seco da população de bactérias em geral, das resistentes aos antibióticos estreptomicina e cloranfenicol, e de actinomicetos. A população de actinomicetos ocorreu no solo principalmente como esporos, e as variações das relações esporos/hifas entre os solos não-rizosférico e rizosférico não foram significativas. Os resultados evidenciam que o cultivo da soja influenciou de forma diferenciada a população desses solos.The effect of soybean cultivation on the population dynamics of the bacterial community was evaluated in two "Cerrado" soils of São Paulo State, Brazil. The experimental areas, in the vicinities of the cities of São Carlos and Barretos, were previously cultivated, respectively, with Paspalum notatum and Brachiaria decumbens. The bacterial population densities in these soils varied from 398.1 x 10³ to 467.7 x 10³ cfu (colony forming units) and from 123 x 10³ to 218.8 x 10³ cfu/g of dried soil, respectively, in São Carlos and Barretos soils. Soybean cultivation in both soils resulted in increments in the total bacterial population density, in the actinomycetes population, and in the bacterial population resistant to the antibiotics streptomycin and chloramphenicol. Actinomycetes were present in these soils mainly as spores. Soybean cultivation did not alter the actinomycetes spores/hyphae ratio when comparing rhizospheric and non-rhizospheric soils. The results show that soybean cultivation affected the bacterial population of these soils.

The occurrence of actinomycetes from rhizospheric soils of Parmelia sp and Solanum lixioides was investigated. The rhizospheric effect from Parmelia sp (Lichen) upon actinomycetes isolates was evaluated and was (R/5 ~ 2.5), while by the solanaceae the resultant ratio R/5 was

Nos ambientes tropicais, os Cerrados destacam-se pelo seu potencial agrícola. Apesar das funções dos microrganismos no crescimento das plantas e na produtividade das culturas, existem poucas informações dos efeitos resultantes do manejo do solo, na ecologia microbiana. Neste estudo, foram avaliados os efeitos das condições ambientais e das práticas agrícolas sobre as populações bacterianas. As densidades das populações em solos com vegetação nativa foram variáveis e diferenciadas. Em Sete Lagoas, MG, as populações de actinomicetos variaram de 1,7 a 50 X 10(4) UFC/g de solo seco, enquanto em Planaltina as densidades das populações bacterianas em solo com primeiro e segundo ano de cultivo de soja foram semelhantes, mas superiores ao solo com vegetação nativa. A utilização agrícola deste solo não resultou em desequilíbrios acentuados das populações de actinomicetos provenientes de esporos e hifas. As relações esporos/hifas variaram de 1,1 a 5,8. Na rizosfera da soja, os coeficientes de correlação entre as populações de actinomicetos com as demais populações bacterianas foram significativos. Os resultados evidenciam que as práticas agrícolas utilizadas na introdução da cultura da soja em solos de Cerrados pode influenciar o equilíbrio das populações na comunidade bacteriana.Among tropical environments, Cerrados stand out because of its agriculture potencial. Although microorganisms play an important role on soil sustainability and crop production, few information is available on the effects of soil management systems on Cerrado's microbial ecology. In this study the effects of environmental conditions and soil management practices on bacterial populations were evaluated. Bacterial population densities in soil under native vegetation were variable and diferentiated. Actinomycetes densities varied from 1.7 to 50 X 10(4) CFU/g dry soil in Sete Lagoas region, Brazil, whereas bacterial populations in both the first and second year of land use were similar and higher than those from soil under native vegetation in the Planaltina region. Soil management practices did not cause strong modifications in the equilibrium among actinomycetes populations obtained from both spores and hyphal. The spore/hypha ratios varied from 1.1 to 5.8. Correlation coefficients among actinomycetes and other bacteria populations were signifficant in soybeans rhizospheres. Results show that soil management practices used for soybean cultivation in Cerrado soils may influence the equilibrium of bacterial populations.

As atividades relacionadas com mineração e indústria metalúrgica são responsáveis pela poluição de extensas áreas de solo em todo o mundo, sendo seus efeitos ainda pouco conhecidos nas condições brasileiras. No presente trabalho, os teores totais e solúveis em água de metais pesados, a densidade e a atividade microbiana foram avaliados em 1996, em sete locais de uma área de deposição de rejeitos da industrialização de zinco, em elevado estádio de degradação, e num local fora da área contaminada, considerado como referência, no estado de Minas Gerais. Todos os locais contaminados apresentaram elevados teores de metais pesados totais e solúveis em água, atingindo, respectivamente, os seguintes valores máximos, em mg kg-1: 11.969 e 726 de Zn; 109 e 18 de Cd; 1.016 e 0 de Pb e 887 e 8 de Cu. Todas as características biológicas avaliadas foram afetadas pelos elevados teores de metais com exceção do número de amonificadores. O C-biomassa apresentou redução acima de 80% em quatro locais contaminados em relação ao local fora da área contaminada. A respiração basal do solo foi maior no local contaminado coberto com Andropogon sp. e menor nos sítios sem vegetação. O número de actinomicetos e de fungos cultiváveis foi menos afetado pela contaminação que o número total de bactérias. Azospirillum spp. foram detectados apenas no local de referência. Oxidantes de amônio foram verificados em somente dois locais que continham vegetação, enquanto os oxidantes de nitrito foram detectados na maioria dos locais amostrados. Verificou-se a tendência de maior densidade e atividade microbiana nos locais contaminados e com algum tipo de vegetação. A concentração total e solúvel de Zn, de Cd e de Cu correlacionou-se fracamente com as características biológicas, exceto para o qCO2, o qual se mostrou promissor como indicador da contaminação com esses metais. Os dados indicaram uma interação químico-biológica complexa em solos altamente contaminados por metais pesados.

Based on the important role of microorganisms, especially Rhizobacteria called Actinomycetes in soil health and sustainability, we performed a partial identification of different types of soil Actinomycetes isolated from the Botanical Garden of the University of Pereira (JBUTP) as gender relying on Bergey taxonomic key, resulting in the following possible genera Nocardia, Actinopolyspora, Streptomyces, Thermonospora, Micromonospora, Actinobispora; performing at a higher percentage, the genera Nocardia and Streptomyces. [ABSTRACT FROM AUTHOR]

There are microorganisms that are beneficial to plants and are used in specific ways to enhance the germination and growth of crops. The benefits are more if, instead of one specific microorganism, groups of them are inoculated in the substrate to reduce the incidence of diseases induced by phytopathogens that affect the roots. The objective of this study (that has an holistic approach), was to evaluate the variables of height and seedling emergence in the nursery and the incidence by reintroduction of antagonists to Phytophthora capsici in groups of 8, 16, 24 and 32 isolates of microorganisms in the germination substrates of chili pepper (Capsicum annuum) and velvet bean (Mucuna deeringiana). The treatments with groups of antagonists presented at least one of the expected beneficial effects, compared with the control l group, by increasing seed sprouting, seedling height, and showing a lower incidence of P. capsici in the greenhouse. The treatments with greater seedling height in the nursery were the groups with 18, 24 and 32 antagonists that included the group of eight actinomycetes. The best treatment was the group with eight isolates of actinomycetes, which had the highest seedling emergence for both crops in the nursery and the lower incidence of P. capsici in chili pepper in the greenhouse. [ABSTRACT FROM AUTHOR]

Streptomycetes are known for producing secondary metabolites, such as antibiotics and extracellular enzymes, that act in the degradation of complex and recalcitrant molecules, playing an important role in composting processes. Thus, to evaluate the effect of soil inoculation and incubation with streptomycete isolates, in the initial growth stage of tomato seedlings, an experiment was conducted in a completely randomized design, with six streptomycete isolates and a non-inoculated control. The soil was inoculated and incubated for 20 days, before planting. After 30 days, the seedlings were collected for determination of seedling height, stem diameter, dry weight of shoots and roots, and nutrients accumulation in shoots. The streptomycete isolates promoted significant increments in the growth and nutrients contents of tomato seedlings. It is suggested that the 35-days incubation period of the inoculated soil, before planting, promotes the time necessary for the streptomycetes to act in the mineralization of soil organic matter, providing nutrients for plants growth. KEY-WORDS: Actinomycetes; growth promotion; Lycopersicum esculentum (L.) Santa Clara.Os estreptomicetos são conhecidos pela produção de metabólitos secundários, como antibióticos e enzimas extracelulares, que atuam na degradação de moléculas complexas e recalcitrantes, desempenhando papel importante nos processos de compostagem. Neste sentido, com o objetivo de avaliar o efeito da inoculação e incubação de solo com isolados de estreptomicetos, no crescimento inicial de mudas de tomateiro, foram avaliados seis isolados de estreptomicetos, mais o controle não inoculado. O solo foi inoculado com os estreptomicetos e incubado por 20 dias, antes do plantio. Após 30 dias, as mudas foram coletadas para determinação da altura, diâmetro do caule, massa seca da parte aérea e raízes e acúmulo de nutrientes na parte aérea. Os isolados de estreptomicetos promoveram incrementos significativos no crescimento e acúmulo de nutrientes, nas mudas de tomateiro. Acredita-se que a incubação do solo, por 35 dias, antes do plantio, garanta o tempo necessário para que os estreptomicetos atuem na mineralização da matéria orgânica, disponibilizando nutrientes para o crescimento das plantas. PALAVRAS-CHAVE: Actinomicetos; promoção de crescimento; Lycopersicum esculentum (L.) Santa Clara.

El objetivo de esta investigación consistió en comparar la flora microbiana a partir de la metodología convencional implementada en Garagoa, Boyacá, para el tratamiento de residuos sólidos domiciliarios con una metodología experimental que consistió en humectar los residuos con agua en lugar de lixiviado, y no mezclar el material por tratar con otro de distintos tiempos de compostaje; para tal fin, se caracterizaron y determinaron los tamaños poblacionales de heterótrofas totales, pseudomonas, hongos y actinomicetos a partir de muestras tomadas en distintas etapas del proceso. De las distintas muestras analizadas se identificaron hongos de los géneros Cladosporium y Aspergillus, propios del proceso de compostaje, Fusarium, Scopulariopsis, Moniliella, Curvularia y levaduras del género Rhodothorula.En el agar ISP2 (para el aislamiento de actinomicetos) se identificaron diversos morfotipos: bacilos esporulados, bacilos gramnegativos, cocobacilos, cocos grampositivos y una bacteria del género Streptomyces. De acuerdo con los resultados de los tamaños poblacionales de los grupos de microorganismos estudiados no se presentaron diferencias significativas entre los tratamientos evaluados; sin embargo, el mayor promedio de los recuentos se presentó en el tratamiento experimental. Palabras clave: materia orgánica; bacterias; hongos; actinomicetos; compost. Abstract This research was aimed at comparing microorganisms from conventional household solid waste treatment in Garagoa, Boyacá, using an experimental methodology consisting of moistening waste with water instead of lixiviate and not mixing the material to be treated with other material having different composting times (i.e. organic fertilizer). Complete heterotopous, pseudomona, fungi and actinomycete population size were thus characterised from samples taken from different stages of the process. Fungi from the Cladosporium and Aspergillus genera (from composting) were identified from this analysis, as well as Fusarium, Scopulariopsis, Moniliella, Curvularia and yeasts from the Rhodothorula genera. Some morphotypes were identified in the ISP2 agar (for the actinomycete isolate): sporulated bacilli, gram-negative bacilli, cocobacilli, gram-positive coci and one bacterium from the Streptomyces genus. According to the results regarding the population sizes of the microorganism groups studied, no meaningful differences were presented between the treatments being tested; however, the experimental treatment presented the highest average count. Key words: organic material, bacteria, fungi, actinomycete, organic

Conduziu-se experimento na Fazenda do Glória e no Laboratório de Nematologia Agrícola do Instituto de Ciências Agrárias, Universidade Federal de Uberlândia, com objetivo de isolar e quantificar actinomicetos, bactérias esporulantes, celulolíticos, leveduras e solubilizadores de fosfato presentes no solo. O delineamento experimental foi o de blocos casualizados com sete tratamentos e quatro blocos. Os tratamentos foram constituídos de sete diferentes combinações de modos de aplicação de calcário e/ou gesso com e/ou sem mecanização para a incorporação do calcário e gesso. As parcelas foram cultivadas com a soja "Conquistaâ€? e avaliadas nas épocas de semeadura, estádio vegetativo e colheita. As amostras de solo coletadas, foram homogeneizadas e passadas em peneira de 20 mesh. Dez gramas de solo foram adicionados a 90 mL de água, constituindo assim a diluição para celulolíticos (10-1). Agitou-se a 200 rpm por 15 min, e posteriormente diluiu-se para a concentração 10-2 que foi usada para solubilizadores de fosfato e leveduras, e para 10-3, no isolamento de actinomicetos e bactérias esporulantes. Posteriormente, ocorreu o plaqueamento colocando-se 0,1 mL da diluição por placa e incubação a 25ºC. O número de unidades formadoras de colônias (UFC) foi determinado 24 a 48 h para bactérias esporulantes, 3 a 5 dias para leveduras, 5 a 7 dias para actinomicetos e 10 a 15 dias para celulolíticos e solubilizadores de fosfato, após o plaqueamento. O comportamento das populações dos microrganismos estudados não dependeu do manejo aplicado ao solo, mostrando diferenças apenas entre as épocas avaliadas. Para cada microrganismo, o comportamento populacional nas três épocas, foi variável conforme características biológicas próprias de cada um deles associadas às condições químicas e físicas do solo.

Background: Mycetoma is a chronic, infectious and granulomatous process that affects skin, subcutaneous tissue and bone. It is produced by bacteria (actinomycetoma) or fungus (eumycetoma). In Mexico, the most common agent causing actinomycetoma is Nocardia brasiliensis followed by Actinomadura madurae. For diagnosis it is necessary to identify the etiologic agent (grain) by direct exam, culture, and histopathological study. The gold standard treatment is diaminodifenilsulfona (DDS) plus trimethoprim/sulfamethoxazol (TMP/SMX); in patients with bad-prognosis topography and bone and/or visceral affection, amikacin in added to this treatment; thus, the use of kanamycin in the treatment of actinomycetomas arises from the need of an efficacious and low-cost drug. Objective: To show the efficacy of kanamycin, added to trimethoprim-sulfamethoxazole and DDS, in patients with diagnosis of actinomycetomas due to Nocardia brasiliensis and Actinomadura madurae with topography of bad prognosis and bone and/or visceral damage. Patients and method: At the Mycology Service of the Dermatological Center Dr. Ladislao de la Pascua, 20 patients with Nocardia brasiliensis and Actinomadura madurae actinomycetomas resistant to conventional treatment were studied. To the conventional treatment of TMP-SMX (160-800 mg/12 h) and DDS (100 mg/day) kanamycin sulphate (15 mg/kg/day) was added in cycles of 14 days with interval of one month; depending on the clinical features 2-4 cycles of kanamycin sulfate were administered. Results: The clinical improvement was achieved in all patients in a mean time of three months. Cure, corroborated by a microbiological study, was obtained in 18 patiens (90%) in a mean time of seven months. Radiological improvement was observed in 50%-70% of cases. Conclusions: Considering the good clinical and radiological response in our group of study, we propose this therapeutic scheme as an efficient and safe alternative in the treatment of actinomycetomas, with topography of bad prognosis and bone and/or visceral damage. [ABSTRACT FROM AUTHOR]

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