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  • Open access
  • 456 Reads
Ilex guayusa: A systematic review of its Traditional Uses, Chemical Constituents, Biological Activities and Biotrade Opportunities
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Ilex guayusa is an emblematic tree of the Ecuadorian Amazon region, widely used in folk medicine, ritual uses and household and industrial beverages. Despite the daily consumption only a few number of studies have been carried out and the species deserves a deepener bioprospecting activity, also in order to define a new Biotrade strategy for the Ecuadorian amazon region. This review summarizes the ethno pharmacological data and the researches concerning I.guayusa. Promising biological activities have been detected, especially as new source of antioxidant agents due to the presence of phenolic compounds. Also a preliminary study as antidiabetic natural product accounts for new researches.

  • Open access
  • 215 Reads
Environmental impact of livestock systems in the Ecuadorian Amazon
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Converting natural ecosystems into livestock agroecosystems often reduces soil organic carbon content by decreasing its supply source, as well as by increasing erosion losses and organic matter decomposition rate. In this sense, this study aimed at evaluating carbon sequestration and soil structure in livestock systems of the Ecuadorian Amazon. This study was carried out in livestock areas of the Pastaza province, under rainforest and livestock systems with and without trees. We collected disturbed an undisturbed soil samples within the depth 0-10 and 10-30 cm. From these samples, we determined total organic carbon and some structural indexes such as bulk density and soil porosity. The results suggest that the soil use with rainforest sequester more total carbon in comparison with the other management, with average values of 515 Mg C ha-1. The silvopastoral systems store average amounts of 55 to 103 Mg C ha-1, which is affected by the number of trees. The structural indexes presented adequate values in all land uses, reflecting the role of the organic matter as an improvement of the soil structural conditions, which favors aeration, root penetration and a greater uptake of rainwater. Land use change, with the adoption of agroforestry systems (ASs) analogous to the potential use of the Amazon region, become adequate management practices to promote sequestration C in both soil and biomass, as well as maintenance of good structural conditions, which reinforces its role as regulator of the ecosystem and its contribution to the mitigation of global climate change.

  • Open access
  • 128 Reads
Chemometrical analysis of structure-structure and structure-activity trends of cycloartane-based saponins in Astragalus genus

Astragalus genus represents the widest terrestrial plant taxon with more than 2500 species of herbs or shrubs. Under phytochemical aspect, this genus was characterized by a high structural diversity of saponins essentially based on cycloartane. The high number and diversity of saponins offers a strong basis for analysis of structural properties and metabolic trends governing molecular synthesis. Such trends can be highlighted by significant correlations between chemical substitution types/positions and aglycone forms. Beyond general biosynthetic machinery, structure-activity trends represent more specific aspects which are essential to be analyzed for highlighting structural factors influencing activity. These two complementary aims were considered in this paper by statistically analyzing structure-structure (SS) and structure-activity (SA) trends in saponins based on different cycloartane forms of Astragalus genus. For that, 193 saponin structures were statistically analyzed by ordination method to highlight positive and negative trends between different chemical substitutions and aglycone forms. In ordination analysis, the most published pharmacological activities of Astragalus saponins (immunomodulatory, cytotoxic) were considered to identify SA trends which were statistically evaluated by Fisher’s exact test. Results revealed significant contributions of cycloartane forms, glucosylation and/or hydroxylation positions on different studied pharmacological activities. Finally, using the significantly influent structural variables, SAR models were developed by logistic regressions. Statistical analysis of cumulated bibliographic data provides interesting integrative way for understanding biosynthetic rules governing structural diversity and influencing pharmacological activities within a wide metabolites’ family.

  • Open access
  • 145 Reads
Residual Value Iteration Algorithm based on Function Approximation

With respect to the problem of unstable and slow convergence for traditional Value Iteration algorithm, we proposed an improved Residual Value Iteration Algorithm based on Function Approximation. The algorithm combines traditional Value Iteration algorithm and Value Iteration algorithm with Bellman residual, introduces weight factors and constructs new rules to update value function parameter vector. Theoretically, the new rule for updating value function parameter vector can guarantee the convergence of the algorithm and solve the unstable convergence problem of the traditional value iteration algorithm. In addition, the algorithm introduces a new factor, named forgotten factor, to speed up the convergence of the algorithm. Applying the proposed algorithm, Value Iteration algorithm and LSPI algorithm to the traditional Grid World problem, the experiment results show that the FARVI algorithm has a good performance and robustness to different scale problems.

  • Open access
  • 293 Reads
Multiple Linear Regression Model of Thermolysin Inhibitors

Thermolysin is a bacterial proteolytic enzyme, considered by many authors as a pharmacological and biological model of other mammalian enzymes, with similar structural characteristics, such as Angiotensin Converting Enzyme and Neutral Endopeptidase. Inhibitors of these enzymes are considered therapeutic targets for common diseases, such as hypertension and heart failure. In this report, a mathematical model of Multiple Linear Regression, for ordinary least squares, and genetic algorithm, for selection of variables, are developed and implemented in QSARINS software, with appropriate parameters for its fitting. The model is extensively validated according to OECD standards, so that its robustness, stability, low correlation of descriptors and good predictive power are proven. In addition, it is found that the model fit is not the product of a random correlation. Two possible outliers are identified in the model application domain but, in a molecular docking study, they show good activity, so we decide to keep both in our database. The obtained model can be used for the virtual screening of compounds, in order to identify new active molecules.

  • Open access
  • 161 Reads
Relationship between two species of age and cattle protozoa in the Ecuadorian Amazon
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Agricultural activity is a feasible alternative in the Amazon as long as technologies are used to generate social, environmental and economic benefits without changing the ecology of the system. In the Amazon region has made ​​work that showed different distribution, geographic presence and incidence of various parasitic genera that affect cattle. The aim of the present study was to evaluate the association between age and protozoa in cattle under free grazing in Canton Arosemena Tola Province Napo - Ecuador. 147 cattle feces were sampled during March 2011 and November 2012. The collection of faeces was carried out during the early hours of the morning and were obtained directly from the rectum of the animal. Coproparasitological analyzes were performed at the Laboratory of Parasitological Diagnosis Vetetinario Chaco-Ecuador. Of the total number of sampled animals were divided into two groups: ≤ twelve months (31) and ≥ to twelve months of age (116). The relationship between protozoa and age was assessed with a test of homogeneity based on Chi-square statistics (P <0.05) and hypothesis test for continuous variables, Student t according to (P <0.05). In both types of parasites Coccidia and Balantidium are significant (Chi2 (P <0.0001) among children ages twelve months and older than twelve months. The protozoa coccidia especially their presence is more dangerous during the first year of life so positive that 20% of them in that period have no presence. Although a negative result is high percentage (58.1) in the presence of coccidia in cattle analyzed. also we should take into account not only the presence, but the parasite load is a necessary thing for an upcoming job. We conclude that there is an association between the presence of protozoa and age of cattle.

  • Open access
  • 183 Reads
Agricultural production units (APU’s) at amazon region of Ecuador, Pastaza province and diversified farm as efficient production system  
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This research makes an analysis of the Agricultural Production Units (APU) in Pastaza province. This is the largest province in Ecuador (12% of the country) and in Amazon Region. In this scenario, 56% of its population lives in rural areas. The 88% of APU in Ecuador are constituted from farming families, defining this term as a farmer group that employs basically family workforce for their activity. In fact, 41% of total productive lands in the country is grown as "family farms", corresponding to a total of 618,685 APUs. However, an important part of agricultural production in Amazon region takes place in the "chakras (farm)", which is the traditional way of Kichwa people to grown their crops. In this area, the family feeding opportunities and the income generation are combined. The crops management in the chakra is natural and is based on the ancient practice of Amazonian Kichwa´s. The chakra also become a family space for knowledge and to keep a high species biodiversity, which sometimes is affected by the increase of the commercial crops surface. At the Centre for Research, Post-degree and Conservation of the Amazonian Biodiversity (CIPCA), belonging to Universidad Estatal Amazónica, a “diversified chakra” is developed in an area of 5000 m2. These researches are focused in the management of a high species diversity based on agroecological principles. The goals are addressed to propose the chakra as a productive model and to spread the results in this Amazonian region.

  • Open access
  • 94 Reads
The milk industry seen from the farms of producers in the Ecuadorian Amazon.
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The food industry is important in the Ecuadorian Amazon, so it is necessary to characterize the processes that intervene in the quality and quantity of milk production. A survey was carried out in which 82 milk producing farms and 35 variables related to the processes of feeding, reproduction, production and animal health were analyzed, with an analysis of Principal Components that showed that the efficiency of production. Of milk is affected by three factors that influence 71% of the variance explained in the system and that relates variables to the productive and reproductive processes. The first component related to the variables, number of cows, calves, heifers, total births, births rate, load capacity of  system the explains the 47.53% of the accumulated variance, the second component inferred in the variables service period, calving-calving, and age at incorporation into reproduction. It is concluded that if production of milk in quantity and quality is desired for the industry, attention must be paid to processes related to production and reproduction on the farms of producers.


  • Open access
  • 201 Reads
Quantification and characterization of native microorganisms under contrasting rainforest environment in Ecuadorian Amazon
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Ecuadorian Amazon Region is known as one of the richest biodiversity environment worldwide. However, it is a fact that microorganisms biodiversity have been poorly studied. In order to contribute to unravel microbe biodiversity and applications, this research aimed to quantify and characterize native microorganisms associated with cocoa (Theobroma cacao) plantations under high cadmium levels in two contrasting Ecuadorian Amazon conditions (CIPCA and Ahuano). Soils samples were collected from two deeps levels (0-10 cm and 10-30 cm) to compare the number of bacteria and fungi in both environments assessed. For microorganisms quantification, decimal dilution methods was performed and most probable number was calculated. Bacteria biodiversity was assessed by isolation of every different single colony and morpho-cultural characterization was performed measuring: colour, growth, shape, elevation, edges, Gram stains and morphology. Fungi biodiversity was evaluated by mycelia shape, colour and radial growth. Results showed the increase in bacteria and fungi under CIPCA environment, where the rainy range was not so high. However, in both ecosystems from 10-30 cm deep, the number of microorganisms were remarkable as compared with 0-10 cm deep. Bacteria characterization highlighted a huge diversity, with 22 different isolates in CIPCA and 16 isolates in Ahuano. For fungi, the differences in morpho-cultural characteristics within both ecosystems were not wide, but also CIPCA had a high diversity with 25 different isolates as compared with 22 from Ahuano. These results are the base for further researches related with microbe applications, such as cadmium bioremediation.

  • Open access
  • 117 Reads
Low productivity and quality of the primary link of the cattle production chain as an input for the industry in the Ecuadorian Amazon Region.
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The objective of the study was to evaluate the main causes that affect the low productivity and quality of the primary link of the cattle production chain as an input for the food transformation industry and related to other destinations in the Ecuadorian Amazon region. Questionnaire were conducted with 399 variables from each of the Amazonian provinces to evaluate behavior in the productive, environmental, economic and social dimensions of livestock systems and animal behavior of the different breeds. The results were analyzed once the livestock systems were typified in each productive purpose, we analyzed the discrete variables that affect the behavior of the systems, related to the productive dimensions (individual milk production and birth rate) and ANAVA for breeding breeds more frequent in each of the provinces. The composition of the systems in the RAE showed that the most frequent breeds are Criollo (35.9) and mestizos without records (63.3%) with a specialized breed deficit that means that the agroindustrial sector is almost non-existent. The Norman races; Holstein and Brown Swiss present births of 82.47; 78.19 and 66.47% respectively, however they do not express their milk production potential due to the management system used. It is concluded that the link that presents the greatest vulnerability is the primary one (livestock farmers) mainly because in the RAE are producing with important productive deficiencies.