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In the current research, the effects of fluid inoculum of Brevibacillus sp. B65, a plant growth promoting microorganism (PGPM), on growth of V. unguiculata subsp. sesquipedalis cultivated in organoponic conditions were evaluated in comparison with traditional inorganic and organic fertilizers. Plant growth promotion of Yardlong bean was assessed through the effects of four different treatments on plant growth and development traits, as well as on crop yield. The four treatments were NPK-inorganic fertilizer (T1), organic matter alone (T2), fluid inoculum of B65 alone (T3) and inoculum supplemented with organic matter (T4). The inoculum of B65 supplemented with organic matter improved different traits of plant growth and development such as seed germination, root development, plant and leaves growth, flowering, as well as crop yield. The main impact of the inoculation mixture was on seed emergence. In the present research, it was demonstrated that biostimulation of Vigna unguiculata subsp. sesquipedalis through inoculation of PGPM Brevibacillus sp. B65 supplemented with organic matter, may replace traditional organic and inorganic fertilization strategies. The nature of the positive influence of strain B65 on the legume is not well understood yet; however, it could be attributed to bacterial phytostimulation through auxin and ethylene production, as well as P mobilization. Additionally, organic matter supplementation demonstrated a stimulating effect on B65 traits. This is of utmost importance and will have a main impact on the sustainable development of agronomical practices.

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La elección de un método de conservación debe permitir mantener, entre otros parámetros, la viabilidad, pureza y estabilidad de las propiedades de una cepa. Kluyveromyces marxianus CCEBI 2011 es una levadura con atractivas potencialidades biotecnológicas, conservada en la Colección de Cultivos del CEBI mediante dos métodos: transferencia periódica y agua destilada estéril (método de Castellani). En este trabajo, para determinar la eficacia y calidad de los dos métodos utilizados para la conservación de K. marxianus CCEBI 2011, se evaluaron parámetros como viabilidad, pureza e identidad y propiedades biotecnológicas. Por ambos métodos se obtuvo una elevada pureza y una viabilidad de 5,31x1010 células/mL y 6,8x1010 células/mL por el método de Castellani y transferencia periódica, respectivamente. En este último se alcanzaron los mayores valores de tolerancia a etanol (11%), producción de etanol (6,08 ± 0,11 g/L) y actividad pectinolítica (15,29 ± 1,71 U/mL). En los dos métodos se corroboró la clasificación taxonómica de esta cepa como K. marxianus, según el análisis de las regiones ITS1-gen 5,8S ARNr-ITS2. Se demostró que los métodos de conservación empleados son efectivos, y que han mantenido con calidad las potencialidades biotecnológicas de este microorganismo por más de 10 años.

The election of a conservation method should allow maintaining, among other parameters, the viability, purity and stability of the properties of a strain. Kluyveromyces marxianus CCEBI 2011 is a yeast with attractive biotechnological potentialities, conserved at the CEBI Culture Collection by two methods: periodic transfer and sterile distilled water (Castellani method). In this study for determining the efficacy and quality of the two methods being used for the conservation of K. marxianus, we evaluated parameters such as viability, purity, identity and biotechnological properties. For both methods we obtained a high purity and a viability of 5.31x1010 cells/mL and 6.8x1010 cells/ mL, for the Castellani method and the periodic transfer method respectively. In this last method we obtained the highest values for ethanol tolerance (11%), ethanol production (6.08 ± 0.11 g/L) and pectonolitic activity (15.29 ± 1.71 U/mL). For the two methods the taxonomic classification of this strain as K. marxianus was corroborated according to the analysis of the ITSI-gen 5.8S ARNr-ITS2 regions. It was shown that the conservation methods being used are effective and that they have maintained the quality of the biotechnological potentialities of this microorganism during more than 10 years.

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Eighteen aerobic endospore forming strains were isolated from sugarcane rhizosphere in N-free medium. A phenotypic description and analysis of the 5' end hypervariable region sequences of 16S rRNA revealed a high diversity of Bacillus and related genera. Isolates were identified, and four genera were obtained: seven strains belonged to Bacillus (Bacillaceae family), four belonged to Paenibacillus, six belonged to Brevibacillus and one strain was identified as Cohnella (Paenibacillaceae family). Four Brevibacillus strains showed in vitro inhibitory activity against plant pathogens fungi Curvularia and Fusarium. Seventy-four percent of the isolated bacteria grew on pectin as the only carbon source, showing polygalacturonase activity. Pectate lyase activity was detected for the first time in a Brevibacillus genus strain. All isolates showed endoglucanase activity. Calcium phosphate solubilisation was positive in 83.3% of the isolates, with higher values than those reported for Bacillus inorganic phosphate solubilising strains. High ethylene plant hormone secretion in the culture medium was detected in 22% of the bacteria. This is the first report of ethylene secretion in Paenibacillaceae isolates. Indole-3-acetic acid production was found in a Brevibacillus genus isolate. It was reported for the first time the presence of Cohnella genus strain on sugarcane rhizosphere bearing plant growth promoting traits. The sugarcane isolate Brevibacillus B65 was identified as a plant growth inoculant because it showed wider spectra of plant stimulation capabilities, including an antifungal effect, extracellular hydrolases secretion, inorganic phosphate solubilisation and plant hormone liberation. In this work, sugarcane was shown to be a suitable niche for finding aerobic endospore forming 'Bacilli' with agriculture biotechnological purposes.

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Yeasts have numerous applications in modern and traditional biotechnology. They take place in production of food, unicellular protein and products with added value, and in the last decades they have been incorporated to the biotechnology industry as host in the production of eukaryotes proteins. Apart from their advantages, some genera are the causes of mycosis on man and in some cases, are opportunistic pathogens associated to diseases such as HIV. They are also agents responsible for the damaging of fresh and elaborated food for human consumption. For these reasons, the quick and accurate identification of industrially, environmentally and clinically significant yeasts is important. Yeast taxonomy has been supported by conventional techniques, based on morphological and physiological descriptions of species and genera, but depend on strain culture conditions, therefore they have introduced errors in yeast taxonomy and originated the duality of their nomenclature. These difficulties have been solved with the application of molecular techniques, based on the sequence analysis of nucleic acid, specially karyotiping electrophoresis, microsatellite analysis, mitochondrial DNA length polymorphism, restriction fragment length polymorphism of ribosomal RNA, ramdom amplified polymorphic DNA and low molecular weight RNA. In this review all those methods are described, which have allowed the development of identification kits for clinical and industrial application for the clearance of phylogenetic relationships among species and genera of yeasts of biotechnological interest.

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La contaminación microbiana de alimentos es un problema serio para la industria alimentaria por las grandes pérdidas económicas que trae consigo. Este fenómeno es mixto por la participación de bacterias, hongos filamentosos y levaduras, pero ha sido estudiado mayormente en bacterias y hongos filamentosos por su protagonismo en el daño. Aunque el papel de las levaduras es secundario en la contaminación microbiana de alimentos, las condiciones ambientales de preservación de estos, que tienden a inhibir el crecimiento de bacterias, han favorecido la aparición de levaduras contaminantes, causantes igualmente de afectaciones en los parámetros organolépticos de buena calidad en alimentos frescos, semi-elaborados y elaborados. En este trabajo se reportan los principales grupos de levaduras Ascomycetes y Basidiomycetes que alteran alimentos de origen vegetal, frutos, verduras y granos; productos de panadería; alimentos elaborados en salmueras y ácidos; leche y productos lácteos; así como carnes frescas y curadas

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