Rhizobacterial Isolates from Prosopis limensis Promote the Growth of Raphanus sativus L. Under Salt Stress.

Microbial biotechnology employes techniques that rely based on the natural interactions that occur in ecosystems. Bacteria, including rhizobacteria, play an important role in plant growth, providing agricultural crops with an alternative that can mitigate the negative effects of abiotic stress, such as those caused by saline environments. In this study, bacterial isolates were obtained from soil and roots of Prosopis limensis Bentham from the department of Lambayeque, Peru. This region has high salinity levels, therefore, the collected samples were used to isolate plant growth-promoting rhizobacteria (PGPR), which were identified through morphological, and physical-biochemical characteristics. These salt tolerant bacteria were screened phosphate solubilization, indole acetic acid, deaminase activity and molecular characterization by 16S rDNA sequencing. Eighteen samples from saline soils of the Prosopis limensis plants in the northern coastal desert of San Jose district, Lambayeque, Peru. The bacterial isolates were screened for salt tolerance ranging from 2 to 10%, a total of 78 isolates were found. Isolates 03, 13 and 31 showed maximum salt tolerance at 10%, in vitro ACC production, phosphate solubilization and IAA production. The three isolates were identified by sequencing the amplified 16S rRNA gene and were found to be Pseudomonas sp. 03 (MW604823), Pseudomonas sp. 13 (MW604824) and Bordetella sp. 31 (MW604826). These microorganisms promoted the germination of radish plants and increased the germination rates for treatments T2, T3 and T4 by 129, 124 and 118% respectively. The beneficial effects of salt tolerant PGPR isolates isolated from saline environments can be new species, used to overcome the detrimental effects of salt stress on plants. The biochemical response and inoculation of the three isolates prove the potential of using these strains as a source of products that can be employed for the development of new compounds proving their potential as biofertilizers for saline environments.

High Retention and Purification of Bromelain Enzyme (Ananas comosus L. Merrill) from Pineapple Juice Using Plain and Hollow Polymeric Membranes Techniques.

The demand for bromelian and pineapple fruit has been increasing substantially in the world because of their benefits for the human health and use in diverse areas. In this context, this work aimed to study the capacity of higher retention (concentration); bromelain activity underwent ultrafiltration from pineapple juice (Ananas comusus L. Merrill). All assays were carried out at pH 7.0 and 7.5, and at 0.05 and 0.40 bar of transmembrane pressures. Results have shown that at the best operating conditions, between 85 and 87% of bromelain activity was recovered using the plain membrane separation process at 0.05 bar. The ultrafiltration has shown the capacity to retain 100% of proteolytic activity of the bromelain extracted. The samples have kept the same physics properties after ultrafiltration, and the result was verified via electrophoresis. The bromelain enzyme obtained was characterized, and pH 7 and between 30 and 40 °C were the best conditions. Therefore, this work shows that the use of both polymeric membranes has shown high efficiency, and can be used in the purification of bromelain enzymes.

Aislamiento e identificación de microrganismos ambientales del museo Tumbas Reales de Sipán / Isolation and identification of the environmental microrganism of the Tumbas Reales de Sipán museum

RESUMEN Las bacterias y los hongos son un riesgo potencial para el material arqueológico y trabajadores de los museos en Lambayeque, Perú. Con el objetivo de cuantificar la microbiología ambiental aislada del museo Tumbas Reales de Sipán, se muestrearon cuatro almacenes, con Agar Nutritivo y Agar Papa Dextrosa, incubándose a 30 °C, en aerobiosis, hasta por 7 días, para bacterias y, hasta por 10 días, para hongos. Se cuantificaron bacterias con un máximo de 2,7x104 UFC cm-2, en las superficies de pisos y paredes; 1,4x103 UFC m-3, en el aire y hongos filamentosos, con un máximo de 7,5x104 UFC cm-2, en las superficies y 9,1x104 UFC m-3, en el aire. Se aislaron e identificaron los géneros de bacterias: Bacillus, Micrococcus, Acinetobacter, Nocardia, Streptococcus, Staphylococcus y Streptomyces y los géneros de hongos filamentosos: Aspergillus, Cladosporium, Circinella, Syncephalastrum, Penicillium, Alternaria, Staphylotrichum, Cercospora, Rhizopus, Cunninghamella, Chrysosporium, Nigrospora, Stachybotrys, Gliocladium y Verticillium.

ABSTRACT Bacteria and fungi are a potential risk to archaeological material and museum workers in Lambayeque, Peru. In order to quantify the isolated environmental microbiology of the Tumbas Reales de Sipán museum, four warehouses were sampled with Nutritive Agar and Papa Dextrose Agar, incubated at 30 °C in aerobiosis for up to 7 days for bacteria and up to 10 days for fungi. Bacteria were quantified with a maximum of 2.7x104 CFU cm-2 on the floor and wall surfaces, 1.4x103 CFU m-3 in the air and filamentous fungi with a maximum of 7.5x104 CFU cm-2 on the surfaces and 9.1x104 CFU m-3 in the air. Bacterial genera were isolated and identified: Bacillus, Micrococcus, Acinetobacter, Nocardia, Streptococcus, Staphylococcus and Streptomyces and the filamentous fungal genera: Aspergillus, Cladosporium, Circinella, Syncephalastrum, Penicillium, Cyrryspunrichum, Cyrrysopositive, Cyrrysylopola Rushingum, Cyrrysophyllizum, Nigrospora, Stachybotrys, Gliocladium and Verticillium.

Rendimiento de polihidroxialcanoatos (PHA) en microorganismos halófilos aislados de salinas / Polyhydroxyalkanoates (PHA) performance of halophilic microorganisms isolated from salty lagoon

En este trabajo se determinó el rendimiento de polihidroxialcanoatos (PHA) producido por microorganismos aislados de suelo y aguas de las salinas de Morrope, Lambayeque, Perú. La población de microorganismos se enriqueció con caldo HM1, con glucosa (15 gL-1) como fuente de carbono, modificado con 15, 20 y 25 g/100 mL de NaCl, se incubó a 30 °C en aerobiosis hasta observar turbidez o película por el crecimiento se aisló en agar HM1 obteniendo cultivos de microorganismos halófilos. En caldo HM2 con glucosa (30 gL-1), con su respectiva concentración de NaCl se investigó la producción de gránulos de PHA y se determinó el tiempo requerido para observar el mayor número de células con gránulos de PHA. Los 20 cultivos con mayor número de células con gránulos se llevaron a fermentación a caldo HM2, cuantificándose la biomasa y PHA. La naturaleza del polímero y cálculo del rendimiento se realizó con cinco aislados microbianos correspondientes a la mayor concentración de NaCl, el mayor número de celular con gránulos en el menor tiempo. Se obtuvieron 234 aislados de microorganismos y en el 38.74% se observó gránulos de PHA mediante la tinción de Sudan Negro B, seleccionándose 20 cultivos de microorganismos con 40 a 85 células con gránulos de PHA. La biomasa osciló entre 0.005 a las 72 horas y 3.211 gL-1 a las 240 horas. El rendimiento p/x fue de 0.270 a 0.725 gg-1, destacando con más de 60% los microorganismos AE222 (60.73%), AE2019 (63.10%) y AE228 (72.52%). Estos microorganismos son considerados promisorios para la producción de PHA.

In this work, we determine the polyhydroxyalkanoates (PHA) yield of microorganisms of soil and water from salty lagoons of Morrope, Lambayeque, Peru. Microorganisms were enriched in modified HM1 broth with 15, 20 and 25 g/100 mL of NaCl, incubated at 30 °C in aerobiosis. After observed turbidity or film, aliquots were taken and seeded on HM1 agar obtaining 234 bacterial isolates that by lipophilic Sudan Negro B staining were observed the presence of 93 bacterial isolates with PHA granules, which were cultured in HM² broth with their respective concentrations of NaCl for 144 hours, quantifying a range of 4-85 cells with granules in five microscopic fields observed, selecting 20 bacterial isolates with the presence of 40-85 cells with granules, then they were taken to fermentation where the optimal incubation time was determined, where the cells are clearly differentiated with PHA granules. To determine the nature of the polymer produced, five bacterial isolates corresponding to the culture with the highest concentration of NaCl and the highest number of cells with PHA granules with the shortest growth time, but not necessarily the highest biomass, were selected, these reached 0.500; 0.300; 0.167; 0.183 and 0.417 gL-1 of PHA, with 1.850; 0.522; 0.275; 0.290 and 0.575 gL-1 of biomass and 0.270; 0.575; 0.607; 0.631 and 0.725 gg-1 yield Y (p/x). The highest yield was 72.52% of cellular mass in PHA being considered a promising and profitable performance for the extraction of the polymer.

Draft Genome Sequence of Halomonas sp. HG01, a Polyhydroxyalkanoate-Accumulating Strain Isolated from Peru.

Halomonas sp. strain HG01, isolated from a salt mine in Peru, is a halophilic aerobic heterotrophic bacterium accumulating poly-3-hydroxybutyrate and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from different carbon sources. Here, we report the draft genome sequence of this isolate, which was found to be 3,665,487 bp long, with a G+C content of 68%.