Amazonian State University
Puyo, Ecuador
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Maddela N.R.,Amazonian State University | Masabanda M.,University Las Fuerzas Armadas | Leiva-Mora M.,University "Marta Abreu" of Las Villas
Water Science and Technology | Year: 2015

Isolating new diesel-oil-degrading microorganisms from crude-oil contaminated sites and evaluating their degradation capacities are vitally important in the remediation of oil-polluted environments and crude-oil exploitation. In this research, new hydrocarbon-degrading bacteria and fungi were isolated from the crude-oil contaminated soil of the oil-fields in the Amazon rainforest of north-east Ecuador by using a soil enrichment technique. Degradation analysis was tracked by gas chromatography and a flame ionization detector. Under laboratory conditions, maximum degradability of the total n-alkanes reached up to 77.34 and 62.62 removal ratios after 30 days of incubation for the evaporated diesel oil by fungi (isolate-1) and bacteria (isolate-1), respectively. The 16S/18S rDNA sequence analysis indicated that the microorganisms were most closely (99-100%) related to Bacillus cereus (isolate-1), Bacillus thuringiensis (isolate-2), Geomyces pannorum (isolate-1), and Geomyces sp. (isolate-2). Therefore, these strains enable the degradation of hydrocarbons as the sole carbon source, and these findings will benefit these strains in the remediation of oil-polluted environments and oil exploitation. © IWA Publishing 2015.

Neill D.A.,Amazonian State University | Beltran H.,National Major San Marcos University | Quizhpe W.,National University of Loja
Novon | Year: 2012

Clethra concordia D. A. Neill, H. Beltrán & Quizhpe (Clethraceae), a thin-stemmed shrub or treelet from the sandstone Machinaza plateau in the Cordillera del Cóndor region on the Peru-Ecuador border, is described and illustrated. The new species is distinct from other species of Clethra L. in its small stature and its very small, thick sclerophyllous leaves, which are evidently an ecological adaptation to the highly acidic, nutrient-poor sandstone substrate where it occurs.

Bartels P.J.,Warren Wilson College | Nelson D.R.,East Tennessee State University | Kaczmarek L.,Adam Mickiewicz University | Kaczmarek L.,Amazonian State University | Michalczyk L.,Jagiellonian University
Zootaxa | Year: 2014

For many decades the genus Milnesium was thought to consist of a single, cosmopolitan species: Milnesium tardigradum Doyere, 1840. However, recently the genus has been re-evaluated, and numerous new species have been described. Cur-rently, over twenty extant species and one fossil are recognised, and most appear to have very narrow geographic ranges. It is doubtful that M. tardigradum sensu stricto is truly cosmopolitan, but to evaluate this hypothesis, specimens previously identified as M. tardigradum must be re-examined using newly proposed taxonomic characters. As part of the All Taxa Biodiversity Inventory (ATBI) we collected Milnesium specimens from various locations in the Great Smoky Mountains National Park (GSMNP). Two Milnesium species have been evaluated, and one of them, Milnesium bohleberi sp. nov., is new to science. The new species is most similar to M. eurystomum but differs by shorter claws and a shorter, narrower, and more cylindrical buccal tube. The other Milnesium species, very rare in our collection, is morphologically indistin-guishable from Milnesium granulatum Ramazzotti 1962, which was previously known only from Chile, Italy and Roma-nia. Based on the recently revised description of M. tardigradum sensu stricto, this nominal species for the genus has not been found in the GSMNP samples. Copyright © 2014 Magnolia Press.

Raju M.N.,Amazonian State University | Venkateswarlu K.,Sri Krishnadevaraya University
Environmental Monitoring and Assessment | Year: 2014

The impact of repeated applications of buprofezin and acephate, at concentrations ranging from 0.25 to 1.0 kg ha-1, on activities of cellulases, amylase, and invertase in unamended and nitrogen, phosphorous, and potassium (NPK) fertilizer-amended soil planted with cotton was studied. The nontarget effect of selected insecticides, when applied once, twice, or thrice on soil enzyme activities, was dose-dependent; the activities decreased with increasing concentrations of insecticides. However, there was a rapid decline in activities of enzymes after three repeated applications of insecticides in unamended or NPK-amended soil. Our data clearly suggest that insecticides must be applied judiciously in pest management in order to protect the enzymes largely implicated in soil fertility. © 2014 Springer International Publishing Switzerland.

Kaczmarek L.,Adam Mickiewicz University | Kaczmarek L.,Amazonian State University | Michalczyk L.,Jagiellonian University | McInnes S.J.,British Antarctic Survey
Zootaxa | Year: 2015

This paper is the second monograph of nine that describes the global records of limno-terrestrial water bears (Tardigrada). Here, we provide a comprehensive list of non-marine tardigrades recorded from South America, providing an updated and revised taxonomy accompanied by geographic co-ordinates, habitat, and biogeographic comments. It is hoped this work will serve as a reference point and background for further zoogeographical and taxonomical studies. © 2015 Magnolia Press.

In Haiti, wood and charcoal are important sources of domestic fuel, and wood-cutting for fuel is a major cause of degradation of the region's dry forests, together with livestock pasturing (cattle and goats). In the Dominican Republic across the border, while the situation was similar some thirty years ago, conditions have changed and dry forests are showing signs of regeneration. The southernmost part of the border area between the two countries, around Anse-à-Pitre and Pedernales, offers an opportunity to compare the condition of dry forests on either side of the border, where the climatic and geological conditions are virtually identical. Our study shows denser tree and shrub cover and higher trees on the Dominican Republic side and a larger number of individual trees regenerating from multiple stems on the Haitian side. In general, the species composition is similar on both sides of the border, but there are significant differences in their frequency and abundance-dominance. Acacia scleroxylon, Amyris elemifera, Bursera simarouba, Capparis ferruginea and Guaiacum sanctum are more frequent in the Dominican Republic, while Acacia macracantha, Senna atomaria, Phyllostylon brasiliense and the two cacti Pilosocereus polygonus and Opuntia sp. are more frequent in Haiti. These differences may be attributed to the autecology of the species (e.g. capacity for colonising disturbed terrain and for vegetative regeneration) rather than to preferences for their use such as for firewood and charcoal.

Neill D.A.,Amazonian State University | Asanza M.,Amazonian State University
Novon | Year: 2012

Lozania nunkui D. A. Neill & Asanza (Lacistemataceae), a new species from the Cordillera del Cóndor region of southeastern Ecuador and adjacent northern Peru, is described and illustrated. It is distinguished from other species in the genus by the glabrous, entire, relatively thick and coriaceous, sclerophyllous leaves, and uniquely, by the five or occasionally six sepals, rather than four sepals as in all other known species. The new species is restricted to nutrient-poor, highly acidic sandstone plateaus within its range, and the thick sclerophyllous leaves appear to be an ecological adaptation to that edaphic condition.

Vasco C.,Amazonian State University
Journal of Agriculture and Rural Development in the Tropics and Subtropics | Year: 2014

This paper analyses the determinants for rural Ecuadorian households to participate in community works, to exchange labour, and to use paid labour. The results show that participation in community work is more common among indigenous peoples who are more committed with community and live in areas with relatively high population densities. Exchange labour agreements are more common among indigenous households settled in areas where industrial agriculture has not penetrated yet. Instead, paid labour is used by small and educated households which have access to credit.

Chemical characteristics of 36 soil sections under natural forests from the Cordillera Central of the Dominican Republic were analyzed. 20 of them had been taken from interfluves, peaks and ridges, and the other 16 were taken from riparian environments. In the interfluves, acidic soils predominate, with high values of saturation of Al, while at riparian sites there are more slightly acidic soils, without or with low levels of free Al. In riparian environments, soils tend to be less acidic and less Al saturated. The variability of pH and Al saturation is not related to altitude in the study area. In the interfluves, soils at sites with steeper slopes tend to be less acidic, and this probably is due to geomorphologic processes, which influence soil development. © 2015 Universidad de los Andes. All rights reserved.

Terpenes are the main constituents of essential oils in plants. They play a considerable role in prevention and therapy of several diseases and constitute building blocks for the synthesis of many useful compounds. In recent years a significant preference towards biotransformation processes has been carried out by using microbial cells as biocatalysts and gathering particular interest for the high production yield of high purity compounds and for their eco-friendly technological approach. The purpose of this study was to investigate the biotransformation of the essential oil of Piper aduncum L., a plant used in traditional Ecuadorian medicine for its antiseptic and antibiotic properties, by endophytic fungi isolated from aerial parts of the plant. Biotransformations applied to terpene phytocomplexes and to their isolated pure chemicals by endophytic micro-organisms isolated from the same plant represent a new approach to the production of new molecules by in vitro strategies. Piper aduncum essential oil has been obtained by steam distillation of wild aerial parts of adult plants collected in Wasakentsa (Ecuador), in January 2006 and supplied by Fundacion Chankuap (Macas, Ecuador). The startup of the research has then been carried out at University of Ferrara Lab performing chemical composition of the essential oil by GC-MS, while the endophytic fungi isolation and subculturing of pure strains on PDA has been processed at CiVaBi (Universidad Politecnica Salesiana, Ecuador). Taxonomic identification of the strains evidencing biotransformation capacity is still in progress. The endophytic fungal strains to be tested for biotransformation activity have been inoculated in 250 ml sterile flasks with PDB liquid medium; after seven days of growing aliquots of whole essential oil or of pure terpene compounds have been added. At different times, samples of biotransforming broth have been collected and monitored for oxidation-reduction reactions. The main components of P. aduncum essential oil, i.e. dillapiol, trans-ocimene, piperitone and terpinen-4-ol, were tested for biotransformation. The biotransformation activity was recorded on two compounds: piperitone and transocimene. Piperitone was transformed into 6-hydroxy-piperitone by EC19 strain evidencing the highest biotransformation yield. The trans-ocimene biotransformation showed good results with all strains tested, especially with EC19 strain giving the compounds dimethyl-octatetraene, dimethyl-octatrienol, dimethyloctadiendiol.

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