Algae with potential biotechnological applications in different industries are commonly isolated from the environment in order to obtain pure (axenic) stocks that can be safely stored for long periods of time. To obtain axenic cultures, antibiotics are frequently employed, and cryopreservation is applied to preserve standing stocks. However, many of these now standard methods were developed using strains derived from pristine to near-pristine environments and cold to temperate regions. The potential effect of the said methods on the life cycle and biochemical profile of algae isolates from hyper-eutrophic and constant high-temperature tropical regions is not well understood. These effects could potentially render them unsuitable for their intended biotechnological application. In this study, we conducted a genetic characterization (18S rRNA) and evaluated the effect of purification (the use of the antibiotic chloramphenicol, CAP) and cryopreservation (dimethyl sulfoxide; DMSO–sucrose mix and glycerol) on the growth rate and lipid content of three new tropical freshwater algal isolates: Chorella sp. M2, Chlorella sp. M6, and Scenedesmus sp. R3, obtained from the Ecuadorian coast. The genetic and morphological characterization revealed a clear discrimination between these strains. All strains cultured with CAP exhibited a lower growth rate. Subsequent to cryopreservation, Chorella sp. M2, Chlorella sp. M6, and Scenedesmus sp. R3 presented no significant difference in growth rate between the cryopreservants. Further, a significantly higher lipid content was observed in the biomass cryopreserved with glycerol in relation to the DMSO–sucrose, with Chorella sp. M2 and Chlorella sp. M6 having twice as much as they had in the first treatment. These results highlight the relevance of selecting an appropriate method for storage, as the materials used can affect the biological performance of different tropical species, although it is still to be determined if the effects observed in this study are long lasting in subsequent cultures of these algae.

Algae with potential biotechnological applications in different industries are commonly isolate from the environment in order to obtain pure (axenic) stocks that can be safely stored for long periods of time. To obtain axenic cultures, antibiotics are frequently used, and cryopreservation is applied to keep standing stocks. However, many of these now standard methods were developed using strains coming from pristine-to-low intervened environments and cold-to-temperate regions. Thus, it is still not well understand the potential effect of said methods on the life cycle and biochemical profile of algae isolates from hiper-eutrophic and constant high-temperature tropical regions, which could potentially render them unsuitable for their intended biotechnological application. In this study, we conducted a genetic characterization (18S rRNA) and evaluated the effect of purification (use of the antibiotic chloramphenicol, CPA) and cryopreservation (dimethyl sulfoxide (DMSO)-sucrose mix and Glycerol) on the growth rate and lipid content of four new tropical freshwater algal isolates: Chorella sp. M2, Chlorella sp. M6, Scenedesmus sp. R3, and Coelastrella sp. A2, from the Ecuadorian coast. The genetic characterization showed a clear discrimination between strains. All strains cultured with CPA had a lower growth rate. After cryopreservation Coelastrella sp. A2 did not grow with both methods; Chorella sp. M2, Chlorella sp. M6 and Scenedesmus sp. R3 presented no significant difference in growth rate between the cryopreservants. A significantly higher lipid content was observed in biomass cryopreserved with glycerol in relation to DMSO-sucrose, with Chorella sp. M2 and Chlorella sp. M6 having twice as much in the first treatment. The results highlight the relevance of choosing an appropriate method for storage as the materials used can affect the biological performance of different tropical species, although is still to determine if the effects observed here are long lasting in subsequent cultures of these algae.

Introducción: dengue, enfermedad viral endémica-epidémica, problema de salud pública internacional en términos de morbilidad y mortalidad, transmitida por el mosquito Aedes aegypti.Objetivo: confirmar la presencia de la enfermedad del dengue durante todo el año en una región costera del Ecuador.Metodología: estudio retrospectivo, observacional, de casos de dengue atendidos en el Hospital Liborio Panchana de la ciudad Santa Elena, Ecuador entre enero y noviembre de 2012.Resultados: en el 2012 se encontraron 29 pacientes cuyo diagnóstico inicial fue sospecha y posterior confirmación de dengue. 18 (62.1%) pertenecientes al sexo femenino y 11 (37.9%) al sexo masculino. La edad con más prevalencia de diagnóstico fue los 19 años con 13.8% (n=4), de los cuales, tres fueron mujeres y uno varón. Todos los pacientes eran de la Provincia de Santa Elena, en la costa ecuatoriana. El 82.8%(n=24) son del Cantón de Santa Elena, 10.3% (n=3) del Cantón Libertad y el 6.9% (n=2) del Cantón Salinas. Un 75.86% (n=27) corresponden a enfermedad de dengue sin signos de alarma, un caso de dengue con signos de alarma y uno como dengue grave.No se presentaron fallecidos por esta patología. Se presentaron casos de dengue desde la semana epidemiológica número 4 [4 al 10 de marzo] a la semana número 43 [21 al 27 de octubre], el mayor porcentaje 44.8% (n=18) se presentaron en la semana número 36 [2 al 8 de septiembre].Conclusión: el dengue ya no es una enfermedad estacional, se presenta durante todo el año, debido a que su transmisión es multifactorial. Rev.cienc.biomed. 2015;6(1):79-84

Summary 3Algae with potential biotechnological applications in different industries are commonly isolate 4 from the environment in order to obtain pure (axenic) stocks that can be safely stored for long 5 periods of time. To obtain axenic cultures, antibiotics are frequently used, and cryopreservation 6 is applied to keep standing stocks. However, many of these now standard methods were 7 developed using strains coming from pristine-to-low intervened environments and cold-to-

Many rural areas of Latin America and the Caribbean (LAC) region are economically depressed. Rural sewage treatment in most areas of LAC is deficient or non-existent. Consequently, the possibility of generating economic revenue from treated sewage is an attractive option for deprived areas of developing countries. Given its peculiar characteristics, rural sewage may be coupled with biological systems such as algae for nutrient cycling. Acceptable algae growth and nutrient elimination were obtained from rural sewage whose treatment may have fallen short of current disposal standards. In this study, aerobic systems working on an 8-month cycle at three different volumetric loading rates (Bv) were assessed in relation to the lifetime growth of three algae strains native to Ecuador. Results indicate Chlorella sp. M2 as the optimal algal strain, with the highest growth rate at Bv of 1 g COD L−1 d−1 and a removal of organic-N (30%), PO43–-P (87%) and NH4+-N (95%). Concomitantly, the kinetic constants of the sewage resulted in a low biomass yield coefficient, making the proposed system highly suitable for developing countries. Finally, the proposed partial recovery stream method, combining nutrient recovery with economic resource generation, appears to contain great potential.