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Garcia-Munoz C.,Corporacion Colombiana de Investigacion Agropecuaria CORPOICA | Hernandez L.,University of Costa Rica | Perez A.,University of Costa Rica | Vaillant F.,University of Costa Rica | Vaillant F.,CIRAD - Agricultural Research for Development
Food Research International | Year: 2014

Tropical highland blackberries are a rich source of ellagitannins (ETs), which are metabolized by gut microbiota to yield urolithin, a potentially bioactive compound excreted in urine up to 7. days after ingestion. Following the ingestion of 250. mL of tropical highland blackberry juice, a spot of urine from 26 volunteers collected at 51 ± 4. h was analyzed for urolithin A and B main derivatives (aglycones and glucuronated forms). Three main groups, "no or low urolithin excreters," "predominantly UA derivatives excreters" and "predominantly UB derivatives excreters," were observed. These categories were also unambiguously observed from 9 individuals following the total excretion of ETs' main metabolites over a 4-day period after ingesting one shot of blackberry juice. Although relatively high inter- and intra-individual variabilities were observed, individuals preserved their status during different intervention periods with different amounts of ETs ingested. Accurate UPLC-DAD/ESI-Q-TOF/MS2 allowed the tentative assignment of an identity to 15 other ET metabolites in urine, but profiling did not allow the discrimination of any other compounds aside from UA or UB derivatives. The results highlight the importance of the interaction of gut microbiota composition and the host endogenous excretery system, which may play a major role in the observed inter-individual variability. © 2013 Elsevier Ltd. Source

Garcia-Munoz C.,Corporacion Colombiana de Investigacion Agropecuaria CORPOICA | Vaillant F.,CIRAD - Agricultural Research for Development | Vaillant F.,University of Costa Rica
Critical Reviews in Food Science and Nutrition | Year: 2014

Consumption of dietary ellagitannins (ETs) has been associated with different health benefits. Nonetheless, ETs are not bioavailable as such and are metabolized in vivo. They are partially converted into ellagic acid (EA) in the upper gastrointestinal (GI) tract, but this first metabolite is also poorly bioavailable. In the lower GI tract, EA and residual ETs are metabolized by gut microbiota to produce urolithins, which, together with their conjugate relatives, persist at relatively high concentrations in plasma and urine for days after ingestion of dietary ETs. Thus, ETs and EA may exert local health benefits on the GI tract but systemic health benefits are more likely to result from urolithins. Cellular models suggest that, at physiological concentration, urolithins are active against chronic degenerative diseases. Health benefits have been proven in animal models and during clinical studies. Even so, the crucial involvement of gut microbiota in ET bioconversion induces important variability of physiological response among humans, giving rise to the concept of high and low urolithin producers. This variability among consumers in obtaining potential health benefits from dietary ETs raises new challenges for the functional food industry. Different research perspectives are discussed to tackle this significant issue for nutritionists, food technologists, and consumers. © 2014 Copyright Taylor & Francis Group, LLC. Source

Barrera G.,Institute Agrobiotecnologia | Simon O.,Institute Agrobiotecnologia | Villamizar L.,Corporacion Colombiana de Investigacion Agropecuaria CORPOICA | Williams T.,Institute Ecologia AC | And 2 more authors.
Biological Control | Year: 2011

Thirty-eight isolates of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV), collected from infected larvae on pastures, maize, and sorghum plants in three different geographical regions of Colombia, were subjected to molecular characterization and were compared with a previously characterized Nicaraguan isolate (SfNIC). Restriction endonuclease analysis (REN) using six different enzymes showed two different patterns among Colombian isolates, one profile was particularly frequent (92%) and was named SfCOL. The physical map of SfCOL was constructed and the genome was estimated to be 133.9. kb, with few differences in terms of number and position of restriction sites between the genomes of SfNIC and SfCOL. The PstI-K and PstI-M fragments were characteristic of SfCOL. These fragments were sequenced to reveal the presence of seven complete and two partial ORFs. This region was collinear with SfMNPV sf20-sf27. However, two ORFs (4 and 5) had no homologies with SfMNPV ORFs, but were homologous with Spodoptera exigua MNPV (se21 and se22/. se23) and Spodoptera litura NPV (splt20 and splt21). Biological characterization was performed against two different colonies of S. frugiperda, one originating from Colombia and one from Mexico. Occlusion bodies (OBs) of the SfCOL isolate were as potent (in terms of concentration-mortality metrics) as SfNIC OBs towards the Mexican insect colony. However, SfCOL OBs were 12 times more potent for the Colombian colony than SfNIC OBs and three times more potent for the Colombian colony than for the Mexican colony. SfCOL and SfNIC showed a slower speed of kill (by ~50. h) in insects from the Colombian colony compared to the Mexican colony, which was correlated with a higher production of OBs/larvae. SfCOL is a new strain of SfMNPV that presents pathogenic characteristics that favor its development as the basis for a biopesticide product in Colombia. © 2011 Elsevier Inc. Source

Barrera G.,Institute Agrobiotecnologia | Williams T.,Institute Ecologia AC | Villamizar L.,Corporacion Colombiana de Investigacion Agropecuaria CORPOICA | Caballero P.,Institute Agrobiotecnologia | And 2 more authors.
PLoS ONE | Year: 2013

A Colombian field isolate (SfCOL-wt) of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) is a mixture of different genotypes. To evaluate the insecticidal properties of the different genotypic variants, 83 plaque purified virus were characterized. Ten distinct genotypes were identified (named A through J). SfCOL-A was the most prevalent (71±2%; mean ± SE) showing a PstI restriction profile indistinguishable to that of SfCOL-wt. The remaining nine genotypes presented genomic deletions of 3.8 - 21.8 Kb located mainly between nucleotides 11,436 and 33,883 in the reference genome SfMNPV-B, affecting the region between open reading frames (ORFs) sf20 and sf33. The insecticidal activity of each genotype from SfCOL-wt and several mixtures of genotypes was compared to that of SfCOL-wt. The potency of SfCOL-A occlusion bodies (OBs) was 4.4-fold higher than SfCOL-wt OBs, whereas the speed of kill of SfCOL-A was similar to that of SfCOL-wt. Deletion genotype OBs were similarly or less potent than SfCOL-wt but six deletion genotypes were faster killing than SfCOL-wt. The potency of genotype mixtures co-occluded within OBs were consistently reduced in two-genotype mixtures involving equal proportions of SfCOL-A and one of three deletion genotypes (SfCOL-C, -D or -F). Speed of kill and OB production were improved only when the certain genotype mixtures were co-occluded, although OB production was higher in the SfCOL-wt isolate than in any of the component genotypes, or mixtures thereof. Deleted genotypes reduced OB potency but increased OB production of the SfCOL-wt population, which is structured to maximize the production of OBs in each infected host. © 2013 Barrera et al. Source

Porras M.F.,Corporacion Colombiana de Investigacion Agropecuaria CORPOICA
Zootaxa | Year: 2010

The identification of Eumastacidae is normally based on the study of phallic complex. However, the genus Zeromastax possesses additional characters that easily differentiate it from other eumastacids. These are ten antenomeres, spines located ventrally on the posterior femur, spur in the distal part of hind tibiae, micropterous condition and the phallic complex with subepiphallic sclerite. Two new species are described, Z. aris and Z. malavasei from the Andean region of Colombia, which show differences in external anatomy including the pronotum, shape of tegmina and coloration pattern, as well as several differences in the phallic complex. © 2010 . Magnolia Press. Source

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