Novel Cyanobacterial Diversity Found in Costa Rican Thermal Springs Associated with Rincon de la Vieja and Miravalles Volcanoes: A Polyphasic Approach.

Central America is one of the most important biodiversity hot spots in the world, and Costa Rican microbial communities from thermal springs are the best characterized in the isthmus. Miravalles is an inactive quaternary stratovolcano, and the Rincón de la Vieja is a unique active volcano, in whose slopes diverse hydrothermal springs, such as Las Lilas, are located. These springs harbor extensive microbial mats, whose diversity has been studied. Based on their importance as primary producers, in this study we focused on cultured cyanobacterial diversity from two geothermal environments of northern Costa Rica. Several cultural, molecular and taxonomic techniques were employed to maximize the results of a polyphasic approach. Sample collection sites were physicochemically described, and strains were isolated and characterized by light and electron microscopy. Phylogenetic analysis was performed using 16S rRNA gene sequences and amplified ribosomal DNA restriction analysis (ARDRA). Fifty-six phylotypes were isolated and classified into 21 morphotypes and identified in 14 genera, some of them might be new species within these genera. Furthermore, according to phylogenetic analysis, there are three possible new genera in our collection. Miravalles and Las Lilas thermal springs are reservoirs of novel phylogeographic lineages of phototrophic microorganisms. This study is the first report of strains that belong to the genera Gloeocapsa, Stanieria, Microseira, Klisinema and Oculatella isolated from thermal springs and growing at temperatures above 50°C. We also obtained isolates assigned to Synechococcus, Leptolyngbya spp., and Fischerella, which are considered typical strains in these environments.

Comparison of midgut bacterial diversity in tropical caterpillars (Lepidoptera: Saturniidae) fed on different diets.

As primary consumers of foliage, caterpillars play essential roles in shaping the trophic structure of tropical forests. The caterpillar midgut is specialized in plant tissue processing; its pH is exceptionally alkaline and contains high concentrations of toxic compounds derived from the ingested plant material (secondary compounds or allelochemicals) and from the insect itself. The midgut, therefore, represents an extreme environment for microbial life. Isolates from different bacterial taxa have been recovered from caterpillar midguts, but little is known about the impact of these microorganisms on caterpillar biology. Our long-term goals are to identify midgut symbionts and to investigate their functions. As a first step, different diet formulations were evaluated for rearing two species of tropical saturniid caterpillars. Using the polymerase chain reaction (PCR) with primers hybridizing broadly to sequences from the bacterial domain, 16S rRNA gene libraries were constructed with midgut DNA extracted from caterpillars reared on different diets. Amplified rDNA restriction analysis indicated that bacterial sequences recovered from the midguts of caterpillars fed on foliage were more diverse than those from caterpillars fed on artificial diet. Sequences related to Methylobacterium sp., Bradyrhizobium sp., and Propionibacterium sp. were detected in all caterpillar libraries regardless of diet, but were not detected in a library constructed from the diet itself. Furthermore, libraries constructed with DNA recovered from surface-sterilized eggs indicated potential for vertical transmission of midgut symbionts. Taken together, these results suggest that microorganisms associated with the tropical caterpillar midgut may engage in symbiotic interactions with these ecologically important insects.

Characterization of true-branching cyanobacteria from geothermal sites and hot springs of Costa Rica.

Costa Rica is at the centre of the Mesoamerican biodiversity hotspot. Little is known about cyanobacteria from this region so far. Here, four isolates of the order Stigonematales (section V) were characterized in a polyphasic approach. All strains were isolated from geothermal sites and hot springs of Costa Rica. However, one of them, identified as Westiellopsis sp. Ar73, did not grow at more than 40 degrees C. Based on its identical 16S rRNA to several previously isolated Westiellopsis sp. and Fischerella muscicola strains, a ubiquitous distribution throughout tropical and subtropical regions can be implied. In contrast, the isolates MV9, MV11 and RV14 grew well up to 50-55 degrees C. Based on morphologic, ultrastructural, molecular and physiologic data, MV9, MV11 and RV14 were identified to belong to the genus Fischerella. Two distinct intergenic transcribed spacer (ITS) types, with or without tRNA genes, were detected for all Stigonematales analysed here, indicating ITS polymorphism as a characteristic feature of heterocystous cyanobacteria. In phylogenetic trees, these Fischerella spp. formed a new and distinct clade within the wider lineage of thermophilic Fischerella (Mastigocladus cf. laminosus), which might represent a geographic lineage. Thus, geographic isolation may be an underestimated aspect of microbial evolution. The strains presented here are suitable as new models to study this group of cyanobacteria.

Actividades enzimáticas en aislamientos bacterianos de tractos digestivos de larvas y del contenido de pupas de Automeris zugana y Rothschildia lebeau (Lepidoptera: Saturniidae)

Enzymatic activities of bacteria isolated from the digestive tract of caterpillars and the pupal content of Automeris zugana and Rothschildia lebeau (Lepidoptera: Saturniidae). The enzymatic activities of bacteria isolated from the digestive tracts of caterpillars and the pupal contents of Automeris zugana and Rothschildia lebeau was studied. This digestive tract represents an extreme microenvironment due to its high pH and presence of antimicrobial substances secreted by the insect or derived from ingested plant tissue. At the same time, it contains large amounts of nutrient-rich food, for which microbes may compete among themselves and with the caterpillar. There is little information about the microbiota associated with tropical caterpillar guts, although bacteria from different genera have been isolated from gut and pupae samples. The study of the enzymatic activities generated by these organisms constitutes a starting point to understand their metabolic and physiological relationships with their hosts, and to find enzymes that have potential biotechnological applications. In this study we evaluated several enzymatic activities in two collections of bacteria isolated from caterpillar guts and pupae of the tropical lepidopteran species A. zugana and R. lebeau. Bacteria grown under aerobic conditions were tested for an array of enzymes, including gelatinases, caseinases, lipases, esterases, cellulases, xylanases, amylases and chitinases. Both collections displayed similar patterns of enzymatic activity. No isolate showed activity for all enzymatic tests, but as a whole, at least some bacteria in each collection were able to degrade each substrate tested. Isolates with the same taxonomic identification obtained from caterpillar guts and pupae had almost the same enzymatic activities. In both collections, it was possible to group bacterial isolates according to their enzyme activity pattern. In addition to a heterogeneous ensemble of isolates exhibiting two or less enzymatic activities, there were two groups with at least five activities that showed an apparent specialization for the substrates they were able to use. The first consisted exclusively of isolates of the family Enterobacteriaceae, which were positive for lipolytic and chitinolytic activities, but completely lacked amylasic, cellulolytic and xylanolytic activities. The second group, composed mainly of Gram-positive rods, exhibited the opposite pattern: they were positive for amylasic, cellulolytic and xylanolytic activities, lacked chitinolytic activity and had few isolates with lipolytic activity. This work forms the foundation for future research to explore the biotechnological potential of bacterial isolates from caterpillar guts. Rev. Biol. Trop. 55 (2): 401-415. Epub 2007 June, 29.

El tracto digestivo de orugas constituye un microambiente extremo, debido a su elevado pH y presencia de sustancias antimicrobianas secretadas por el insecto o derivadas del tejido vegetal ingerido. Al mismo tiempo, el intestino alberga gran cantidad de alimento, por el cual los microorganismos presentes podrían competir entre sí y con su hospedero. Existe poca información sobre la microbiota asociada con el intestino de orugas tropicales, aunque se ha demostrado la presencia de bacterias de diversos géneros tanto en el intestino como en el interior de pupas. El estudio de las actividades enzimáticas de estos microorganismos constituye un punto de partida en la comprensión de la posible relación metabólica y fisiológica que establecen con sus hospederos, a la vez que permite investigar enzimas con potenciales aplicaciones biotecnológicas. En este trabajo se evaluó la presencia de actividades gelatinolítica, caseinolítica, esterásica, lipolítica, quitinolítica, amilásica, celulolítica y xilanolítica en dos colecciones de aislamientos bacterianos provenientes de tractos digestivos de orugas y de pupas de los lepidópteros Automeris zugana y Rothschildia lebeau. Se utilizaron ensayos bioquímicos tradicionales para detectar enzimas secretadas en condiciones aerobias, en las que ambas colecciones exhibieron un comportamiento enzimático similar. Ningún aislamiento produjo un resultado positivo en todas las pruebas, pero como conjunto ambas colecciones fueron capaces de utilizar todos los sustratos evaluados. Los aislamientos obtenidos de pupas presentaron prácticamente las mismas actividades que sus homólogos provenientes de intestinos. En ambas colecciones fue posible agrupar los aislamientos de acuerdo con su patrón de producción de enzimas. Además de un conjunto heterogéneo de aislamientos poco activos (dos o menos actividades), se destacan dos grupos muy activos (al menos cinco actividades), que manifiestan una aparente especialización en los sustratos que utilizan. El primero de ellos está constituido exclusivamente por miembros de la familia Enterobacteriaceae, los cuales exhibieron un alto porcentaje de positividad en actividades lipolítica y quitinolítica, pero no demostraron la expresión de las actividades amilásica, celulolítica ni xilanolítica. El segundo grupo, formado en su gran mayoría por bacilos Gram-positivos, presenta la situación opuesta: alta positividad en actividades amilásica, celulolítica y xilanolítica, no detección de actividad quitinolítica y pocos aislamientos con actividad lipolítica. Este trabajo pretende ser la base de futuras investigaciones que exploren el potencial biotecnológico de aislamientos bacterianos provenientes del tracto digestivo de orugas.

[Enzymatic activities of bacteria isolated from the digestive tract of caterpillars and the pupal content of Automeris zugana and Rothschildia lebeau (Lepidoptera: Saturniidae)]. / Actividades enzimáticas en aislamientos bacterianos de tractos digestivos de larvas y del contenido de pupas de Automeris zugana y Rothschildia lebeau (Lepidoptera: Saturniidae).

The enzymatic activities of bacteria isolated from the digestive tracts of caterpillars and the pupal contents of Automeris zugana and Rothschildia lebeau was studied. This digestive tract represents an extreme microenvironment due to its high pH and presence of antimicrobial substances secreted by the insect or derived from ingested plant tissue. At the same time, it contains large amounts of nutrient-rich food, for which microbes may compete among themselves and with the caterpillar. There is little information about the microbiota associated with tropical caterpillar guts, although bacteria from different genera have been isolated from gut and pupae samples. The study of the enzymatic activities generated by these organisms constitutes a starting point to understand their metabolic and physiological relationships with their hosts, and to find enzymes that have potential biotechnological applications. In this study we evaluated several enzymatic activities in two collections of bacteria isolated from caterpillar guts and pupae of the tropical lepidopteran species A. zugana and R. lebeau. Bacteria grown under aerobic conditions were tested for an array of enzymes, including gelatinases, caseinases, lipases, esterases, cellulases, xylanases, amylases and chitinases. Both collections displayed similar patterns of enzymatic activity. No isolate showed activity for all enzymatic tests, but as a whole, at least some bacteria in each collection were able to degrade each substrate tested. Isolates with the same taxonomic identification obtained from caterpillar guts and pupae had almost the same enzymatic activities. In both collections, it was possible to group bacterial isolates according to their enzyme activity pattern. In addition to a heterogeneous ensemble of isolates exhibiting two or less enzymatic activities, there were two groups with at least five activities that showed an apparent specialization for the substrates they were able to use. The first consisted exclusively of isolates of the family Enterobacteriaceae, which were positive for lipolytic and chitinolytic activities, but completely lacked amylasic, cellulolytic and xylanolytic activities. The second group, composed mainly of Gram-positive rods, exhibited the opposite pattern: they were positive for amylasic, cellulolytic and xylanolytic activities, lacked chitinolytic activity and had few isolates with lipolytic activity. This work forms the foundation for future research to explore the biotechnological potential of bacterial isolates from caterpillar guts.

Bacillus thuringiensis in caterpillars and associated materials collected from protected tropical forests in northwestern Costa Rica

Bacillus thuringiensis (Bt) synthesizes crystalline inclusions that are toxic to caterpillars (Lepidoptera) and other orders of invertebrates. Materials associated with 37 caterpillars from 16 species, collected while feeding on 15 different species of host plants in dry, cloud and rain forests located in the Area de Conservación Guanacaste in northwestern Costa Rica, were examined for the presence of Bt. From a total of 101 derived samples, 25 Bt isolates were cultured: 56% from host plant leaves, 8% from caterpillar guts and 36% from caterpillar fecal pellets. Bt was isolated from at least one sample in 38% of the systems constituted by the food plant, gut and fecal pellets corresponding to a single caterpillar. Four different morphologies of crystalline inclusions were observed, with bipyramidal and irregular crystal morphologies being the most prevalent.

Bacillus thuringiensis (Bt) sintetiza inclusiones cristalinas que resultan tóxicas para algunas larvas de lepidópteros y otros órdenes de invertebrados. Su presencia fue examinada en materiales asociados a 37 orugas de mariposas de 16 especies, las cuales fueron colectadas mientras se alimentaban en 15 especies diferentes de plantas hospederas en bosques secos, nubosos y húmedos localizados dentro del Área de Conservación Guanacaste (ACG) en el noroeste de Costa Rica. A partir de un total de 101 muestras se obtuvo 25 aislamientos de Bt: 56% a partir de material foliar de las plantas hospederas, 8% a partir del contenido intestinal de las larvas y 36% a partir de sus excrementos. Esta bacteria fue cultivada a partir de al menos uno de los 3 diferentes tipos de muestra asociados a una oruga particular (planta hospedera, intestino, excremento) en 38% de los casos posibles. En la colección de aislamientos obtenida se observaron cuatro morfologías de inclusiones cristalinas, siendo aquellas bipiramidales e irregulares las más prevalentes.

Bacillus thuringiensis in caterpillars and associated materials collected from protected tropical forests in northwestern Costa Rica.

Bacillus thuringiensis (Bt) synthesizes crystalline inclusions that are toxic to caterpillars (Lepidoptera) and other orders of invertebrates. Materials associated with 37 caterpillars from 16 species, collected while feeding on 15 different species of host plants in dry, cloud and rain forests located in the Area de Conservación Guanacaste in northwestern Costa Rica, were examined for the presence of Bt. From a total of 101 derived samples, 25 Bt isolates were cultured: 56% from host plant leaves, 8% from caterpillar guts and 36% from caterpillar fecal pellets. Bt was isolated from at least one sample in 38% of the systems constituted by the food plant, gut and fecal pellets corresponding to a single caterpillar. Four different morphologies of crystalline inclusions were observed, with bipyramidal and irregular crystal morphologies being the most prevalent.

The windows, scales, and bristles of the tropical moth Rothschildia lebeau (Lepidoptera: Saturniidae)

The common Spanish name of the moth Rothschildia lebeau (Saturniidae)is cuatro ventanas (four ‘windows ’),because it exhibits a transparent oval path in each wing.The scales of the colored areas and the bristles from the "window "were analyzed.We developed a simple device to measure transmittance across the "windows "with an spectrophotometer.A square section of "window "was mounted onto a flat black card and placed onto a clamp that hung in the path of the light -beam of the spectrophotometer.Absorbance was measured at 350 and 550 nm,with the "window "positioned perpendicular to the light beam (incidence of 90 °);then the measurements were repeated with the "window "moved at an angle of 45 °.Each measurement was replicated 5 times.Wing color spots were analyzed with a light dissection microscope (stereoscope)and with scanning electron microscopy.The scales have a minimum of 4 morphological types,3 of them showed the typical appearance of unspecialized scales described for other butterflies; whereas the fourth has features particular to this species. On the "window "the scales are transformed in hair-like bristles that do not interfere with light, conferring the transparency that characterizes the "windows ".However,if the wing is illuminated at an almost grazing-incidence,they reflect the light as a mirror.Two hypothetical functional explanation for the windows are mimicry and interspecies communication

El nombre común de la mariposa nocturna Rothschildia lebeau (Saturniidae)es "cuatro ventanas ",porque exhibe una zona transparente en cada ala.Las escamas de las áreas coloreadas y las cerdas de las "ventanas "fueron analizadas al estereoscopio y al microscopio electrónico de rastreo. Al menos se identificaron cuatro tipos morfológicos de escamas similares a las escamas no especializadas de otras mariposas.En la "ventana "las escamas han sido sustituidas por cerdas que no interfieren el paso de la luz,confiriéndoles la transparencia que las caracteriza.No obstante,si el ala es iluminada en ángulo rasante refleja la luz como un espejo.Dos hipótesis para explicar la evolución de estas "ventanas "son el mimetismo y la comunicación

Percepción de la biotecnología en estudiantes universitarios de Costa Rica / Perception about biotechnology in university students in Costa Rica

A survey was carried out to determine the perception and knowledge about biotechnology and genetically modified organisms (GMOs) in a sample (n=750) of university students from three public universities in Costa Rica: Universidad de Costa Rica, Universidad Nacional and Instituto Tecnológico de Costa Rica. The study revealed that 88% of the students showed a satisfactory level of knowledge about modem biotechnology and 79% of them reported a favorable opinion and good acceptance of this technology. Students would accept some risks associated to biotechnology if it represents an improvement to the competitiveness of Costa Rica. Some differences were detected in the opinions from students of the three universities that can be associated to the area of study. Students from social disciplines showed a higher percentage of negative acceptances to biotechnology and GMOs when their opinions were compared with those of students from life sciences and technologies.

Relación de los cultivos modificados genéticamente con el ambiente y la salud de la población costarricense / Relationship of genetically modified crops with the environment and health of the Costa Rican human population

Genetic engineering and the food derived from genetically modified crops (GMCs) have been the center of debate worldwide, as has occurred historically with the advent of new technologies. Questions are derived from the potential impact of GMCs to the environment and the safety of the products to the consumers. In relation to the first inquiry, practice has been oriented to a case-by-case-study, according to the own characteristics of the GMC, in order to minimize its impact in the environment. Scientific studies in diverse latitudes of the world have demonstrated that GMCs in the market showed no adverse effects related to this issue. In relation to food derived from the GMCs, rigorous evaluation protocols have been developed and approved by FAO and WHO to guarantee the innocuousness of these products. Up to the moment, no contraindications for human health have been pointed out for the products that are available today in the market. In the particular case of Costa Rica, the country has established since the 90s a regulatory biosafety framework for the management of the GMCs, safeguarding the biodiversity of the country and the health of consumers. At the same time the country has made significant public and private investments in the field that allowed the country to obtain a leading position in biosafety in the region and genetic engineering research at national research centers. Any attempt to restrict or prohibit these activities in the country, will put in risk the previously described investment, will affect the generation of new knowledge for decision making and the leadership in the field, preventing the benefits derived from this promising technology.

Unusual microbial xylanases from insect guts.

Recombinant DNA technologies enable the direct isolation and expression of novel genes from biotopes containing complex consortia of uncultured microorganisms. In this study, genomic libraries were constructed from microbial DNA isolated from insect intestinal tracts from the orders Isoptera (termites) and Lepidoptera (moths). Using a targeted functional assay, these environmental DNA libraries were screened for genes that encode proteins with xylanase activity. Several novel xylanase enzymes with unusual primary sequences and novel domains of unknown function were discovered. Phylogenetic analysis demonstrated remarkable distance between the sequences of these enzymes and other known xylanases. Biochemical analysis confirmed that these enzymes are true xylanases, which catalyze the hydrolysis of a variety of substituted beta-1,4-linked xylose oligomeric and polymeric substrates and produce unique hydrolysis products. From detailed polyacrylamide carbohydrate electrophoresis analysis of substrate cleavage patterns, the xylan polymer binding sites of these enzymes are proposed.

The "windows", scales, and bristles of the tropical moth Rothschildia lebeau (Lepidoptera: Saturniidae).

The common Spanish name of the moth Rothschildia lebeau (Saturniidae) is cuatro ventanas (four 'windows'), because it exhibits a transparent oval path in each wing. The scales of the colored areas and the bristles from the "window" were analyzed. We developed a simple device to measure transmittance across the "windows" with an spectrophotometer. A square section of "window" was mounted onto a flat black card and placed onto a clamp that hung in the path of the light - beam of the spectrophotometer. Absorbance was measured at 350 and 550 nm, with the "window" positioned perpendicular to the light beam (incidence of 90 degrees); then the measurements were repeated with the "window" moved at an angle of 45 degrees. Each measurement was replicated 5 times. Wing color spots were analyzed with a light dissection microscope (stereoscope) and with scanning electron microscopy. The scales have a minimum of 4 morphological types, 3 of them showed the typical appearance of unspecialized scales described for other butterflies; whereas the fourth has features particular to this species. On the "window" the scales are transformed in hair-like bristles that do not interfere with light, conferring the transparency that characterizes the "windows". However, if the wing is illuminated at an almost grazing-incidence, they reflect the light as a mirror. Two hypothetical functional explanation for the windows are mimicry and interspecies communication.

[A new species of Euglena (Euglenozoa: Euglenales) isolated from extreme environments in "boiling mudflats" of Rincón de la Vieja volcano, Costa Rica]. / Una nueva especie de Euglena (Euglenozoa: Euglenales) aislada de ambientes extremófilos en las Pailas de Barro del Volcán Rincón de la Vieja, Costa Rica.

A new species of euglena isolated from a hot and acid mud pool located in Las Pailas de Barro, Volcán Rincón de la Vieja, Costa Rica is described. This species inhabits hot and acid environments. Euglena pailasensis sp. nov. main features are: the absence of flagella, the presence filaments like "pilis", the presence of chloroplasts with pyrenoids crossed by several tylakoids, and acid and heat tolerance. Molecular phylogeny studies using 18S rDNA and Gap C genes indicated that the new species is related to E. mutabilis. Its taxonomic characters based on morphology, biology and sequence of the 18S rDNA and Gap C genes are discussed and compared with other closely related species of the genus.

[Ultrastructural description of Euglena pailasensis (Euglenozoa) from Rincón de la Vieja volcano, Guanacaste, Costa Rica]. / Descripción ultraestructural de Euglena pailasensis (Euglenozoa) del Volcán Rincón de la Vieja, Guanacaste, Costa Rica.

The euglenoids are unicellular eukaryotic flagellates living in a diversity of soils and aquatic environments and ecosystems. This study describes the ultrastructure of an euglenoid isolated from the surface of a boiling mud pool with temperatures ranging from 38 to 98 degrees C and pH 2 - 4. The hot mud pool is located in Area de Pailas de Barro, Las Pailas, Rincón de la Vieja Volcano, Guanacaste, Costa Rica. The morphological characterization of the Euglena pailasensis was performed by SEM and TEM. It was determined that, although the euglenoid was obtained from an extreme volcanic environment, the general morphology corresponds to that of a typical member of Euglena of 30-45 microm long and 8-10 microm wide, with membrane, pellicle, chloroplasts, mitochondria, nucleus, pigments and other cytoplasmic organelles. E. pailasensis is delimited by a membrane and by 40 to 90 pellicle strips. It was observed up to 5 elongated chloroplasts per cell. The chloroplast contains several osmiophilic globules and a pyrenoid penetrated by few thylakoid pairs. The nutritious material is reserved in numerous small paramylon grains located at the center of the cell, mitocondria are characterized by the presence of crests in radial disposition toward the interior of the lumen. It was also observed around the external surface "pili" like filaments originating from the pellicle strips. There is no evidence for the presence of flagella in the ampulla (reservoir/canal area), a fact confirmed by negative staining, and a difference regarding other species of Euglena. The observed ultrastructural characteristics are not sufficient to explain the adaptation of this species to acid and hot environments.

[Arthropod collection for biodiversity prospection in the Guanacaste Conservation Area, Costa Rica]. / Recolecta de artrópodos para prospección de la biodiversidad en el area de Conservación Guanacaste, Costa Rica.

This study describes the results and collection practices for obtaining arthropod samples to be studied as potential sources of new medicines in a bioprospecting effort. From 1994 to 1998, 1800 arthropod samples of 6-10 g were collected in 21 sites of the Area de Conservaci6n Guancaste (A.C.G) in Northwestern Costa Rica. The samples corresponded to 642 species distributed in 21 orders and 95 families. Most of the collections were obtained in the rainy season and in the tropical rainforest and dry forest of the ACG. Samples were obtained from a diversity of arthropod orders: 49.72% of the samples collected corresponded to Lepidoptera, 15.75% to Coleoptera, 13.33% to Hymenoptera, 11.43% to Orthoptera, 6.75% to Hemiptera, 3.20% to Homoptera and 7.89% to other groups. Different life stages per arthropod species were obtained in most samples, 54.26% of them were adults, 19.90% corresponded to larvae, 6.46% to pupae, 6.12% to pre-pupae, 2.07% to nymphs and 3.74% to other stages. Other materials associated to insects like frass represented 11.20% of the samples collected. Several collecting methods were explored, based on the possibility of accessing the necessary amount of material causing the less impact. Most of the samples were obtained by manual collection (44.38%),. followed by insects breeding (25.73%), light traps (18.80%), different types of nets (10.52%) and other methods (0.16%). In general, collecting methods and practices excluded the use of solvents, mixing different species or life stages in the same bag, which might have introduced undesirable effects in the screening systems for new compounds. Based on the possibility of finding new chemicals in similar samples associated to one arthropod species, the collecting strategy included the generation of several samples from same species, separated according to differences in life stages, collecting sites, ecosystems. seasons, feeding materials or behavioral aspects. This strategy allowed the generation a larger number of samples submitted to bioassays in different areas of pharmaceutical research.

[Relationship of genetically modified crops with the environment and health of the Costa Rican human population]. / Relación de los cultivos modificados genéticamente con el ambiente y la salud de la población costarricense.

Genetic engineering and the food derived from genetically modified crops (GMCs) have been the center of debate worldwide, as has occurred historically with the advent of new technologies. Questions are derived from the potential impact of GMCs to the environment and the safety of the products to the consumers. In relation to the first inquiry, practice has been oriented to a case-by-case-study, according to the own characteristics of the GMC, in order to minimize its impact in the environment. Scientific studies in diverse latitudes of the world have demonstrated that GMCs in the market showed no adverse effects related to this issue. In relation to food derived from the GMCs, rigorous evaluation protocols have been developed and approved by FAO and WHO to guarantee the innocuousness of these products. Up to the moment, no contraindications for human health have been pointed out for the products that are available today in the market. In the particular case of Costa Rica, the country has established since the 90s a regulatory biosafety framework for the management of the GMCs, safeguarding the biodiversity of the country and the health of consumers. At the same time the country has made significant public and private investments in the field that allowed the country to obtain a leading position in biosafety in the region and genetic engineering research at national research centers. Any attempt to restrict or prohibit these activities in the country, will put in risk the previously described investment, will affect the generation of new knowledge for decision making and the leadership in the field, preventing the benefits derived from this promising technology.

[Perception about biotechnology in university students in Costa Rica]. / Percepción de la biotecnología en estudiantes universitarios de Costa Rica.

A survey was carried out to determine the perception and knowledge about biotechnology and genetically modified organisms (GMOs) in a sample (n=750) of university students from three public universities in Costa Rica: Universidad de Costa Rica, Universidad Nacional and Instituto Tecnológico de Costa Rica. The study revealed that 88% of the students showed a satisfactory level of knowledge about modem biotechnology and 79% of them reported a favorable opinion and good acceptance of this technology. Students would accept some risks associated to biotechnology if it represents an improvement to the competitiveness of Costa Rica. Some differences were detected in the opinions from students of the three universities that can be associated to the area of study. Students from social disciplines showed a higher percentage of negative acceptances to biotechnology and GMOs when their opinions were compared with those of students from life sciences and technologies.

Developing transgenic rice at the University of Costa Rica: perspectives and considerations for managing intellectual property rights

El Programa de Biotecnología de Arroz del Centro de Investigación en Biología Celular y Molecular (RBP-CIBCM), de la Universidad de Costa Rica (UCR), inició en 1990 la caracterización molecular del genoma del virus de la hoja blanca del arroz (RHBV) y el desarrollo de protocolos para el cultivo in vitro y regeneración de variedades indica costarricenses, con la finalidad de producir plantas transgénicas resistentes al virus. La fase siguiente se enfocó en la producción, por medio de ingeniería génetica, de líneas de arroz resistentes al RHBV y al herbicida PPT, mediante la expresión de secuencias de RHBV y del gen ber. Posteriormente se evaluó en ensayos de campo la resistencia al virus y al herbicida, y las características agronómicas de las plantas. Además de la experiencia acumulada durante el proceso de producción de las plantas transgénicas, se incursionó en evaluaciones de campo, para eventualmente liberar las variedades al mercado. Para este propósito, el RBP-CIBCM sigue actualmente una estrategia que incluye evaluar la inocuidad del nuevo alimento, realizar estudios de bioseguridad ambiental e identificar y resolver derechos de propiedad intelectual (DPI). Los objetivos principales de este trabajo contemplan diseñar e implementar políticas de educación y manejo de DPI para el RBP-CIBCM, efectuar una auditoría de las tecnologías e insumo utilizados, y determinar su efecto en la comercialización de los productos. Al mismo tiempo, el Programa explora formas innovativas para la protección de las nuevas variedades y de otros productos de la investigación