Microbiological and physicochemical characterization of a traditionally fermented corn product: "Champús" / Caracterización microbiológica y fisicoquímica de un producto de maíz tradicionalmente fermentado "Champús"

Background: Many native fermented foods in Latin America are made by indigenous communities through processes that preserve their traditions. Among these products is champús, a fermented drink or dessert native to Colombia, Ecuador, and Peru. It has a characteristic flavor between sweet and sour with a low alcohol content, is made from cereals such as corn, wheat, or a mixture of these, and can include fruits and spices. Objectives: This research evaluated the microbiological, physicochemical, and sensory quality characteristics of champús to revalue the consumption of traditional foods. Methods: For this purpose, the microbiological safety criteria, fermenting microorganisms, and physicochemical and sensory parameters were evaluated for two batches of champús prepared by five producers and taking samples at different stages. Results: It was found that the average temperature and relative humidity for processing were between 16.5 ± 2.56 °C and 61.6 ± 9.14 %, respectively, and the products exceeded microbiological criteria such as total coliforms and some microbiological criteria for Escherichia coli and Staphylococcus aureus. There was also a high prevalence of lactic acid bacteria and yeasts throughout the process, with the occurrence of the genera Weissella, Leuconostoc, and Lactobacillus. The presence of organic acids (lactic, acetic, and propionic) and ethanol was evidenced. Champús seems to be a source of calcium, phosphorus, and free amino acids. Conclusions: This information provides a basis to propose improvement plans for small producers and, at the same time, to conduct more detailed studies on the native microbiota of champús

Antecedentes: Muchos de los alimentos nativos fermentados de América Latina son elaborados por las comunidades indígenas mediante procesos que preservan sus tradiciones. Entre estos productos se encuentra el "champús", una bebida o postre fermentado originario de Colombia, Ecuador y Perú. Presenta un sabor característico entre dulce y ácido con un bajo contenido de alcohol, está elaborado a base de cereales como maíz, trigo o la mezcla de estos, y puede llevar entre sus ingredientes frutas y especias. Objetivo: Esta investigación evaluó las características de calidad microbiológica, fisicoquímica y sensorial del champús para revalorizar el consumo de los alimentos tradicionales. Métodos: Se evaluaron criterios de seguridad microbiológica, microorganismos fermentadores, parámetros fisicoquímicos y sensoriales de dos lotes de champús elaborados por 5 productores, tomando muestras en diferentes etapas de proceso. Resultados: Como resultados, se encontró que la temperatura y la humedad relativa promedio de elaboración estuvieron entre 16,5 ± 2,56 °C y 61,6 ± 9,14 % y que los productos superaron los criterios microbiológicos como coliformes totales y algunos criterios microbiológicos como Escherichia coli y Staphylococcus aureus. También hubo una alta prevalencia de bacterias lácticas y levaduras a lo largo del proceso, identificándose los géneros Weissella, Leuconostoc y Lactobacillus. Se evidenció la presencia de ácidos orgánicos (láctico, acético y propiónico) y de etanol. El champús parece ser una fuente de calcio, fósforo y aminoácidos libres. Conclusión: Esta información sirve de base para proponer planes de mejora para los pequeños productores y al mismo tiempo para realizar estudios más detallados sobre la microbiota nativa del champús.

Species limits and introgression in Pimelodus from the Magdalena-Cauca River basin.

Low morphological differentiation among taxa hampers their appropriate identification, basic biological studies and promotion of any conservation effort. Aiming to provide the first insight into the evolution and speciation among north-western South American members of Pimelodus, this study tested the hypothesis that Pimelodus yuma, Pimelodus grosskopfii and Pimelodus crypticus represent three independently evolving species and explored signals of interspecific hybridisation. The outcomes based on mitochondrial (cox1) and nuclear (RADseq, microsatellites and rag2) markers combined with coalescence-based and allele-frequency methods confirmed that each studied species represents an independently evolving unit. Contrary to expectations, P. yuma was found as a sister clade of P. blochii, while P. crypticus (formerly confused with P. blochii) was phylogenetically closer to P. grosskopfii. We also found strong evidence of ancient introgression (0.66-3.32 mya) between the non-sibling species P. yuma and P. grosskopfii, breaking the absence of interbreeding and the independent evolutionary trajectory among north-western South American Pimelodus during their diversification history, a pre-requisite to define species limits. However, there were non-significant values of current gene flow between them, supporting the hypothesis of full isolation.

Population genetics of three threatened catfish species in heterogeneous environments of the Cauca River, Colombia

Neotropical catfishes Ageneiosus pardalis, Pimelodus grosskopfii and Sorubim cuspicaudus are migratory fishes of commercial importance that exhibit decreasing populations due to overfishing and other anthropic interventions. This study used species-specific microsatellite loci to test the hypothesis that threatened fish populations show genetic vulnerability signs and are genetically structured in the middle and lower sections of the Cauca River. The studied species exhibit genetic diversity levels higher than the average values reported for Neotropical Siluriformes; however, they seem to have suffered recent bottlenecks and they present significant endogamy levels that are higher for the critically endangered catfish P. grosskopfii. Furthermore, both Ageneiosus pardalis and S. cuspicaudus are each formed by one genetic group, while Pimelodus grosskopfii comprises two coexisting genetic groups. The information obtained in this study is useful for the decision making in management plans that are appropriate for the sustainability of these three species populations within the proposal for the expansion of the hydroelectric development and other anthropic activities.(AU)

Los bagres Neotropicales Ageneiosus pardalis, Pimelodus grosskopfii y Sorubim cuspicaudus, son peces migratorios de importancia comercial cuyas poblaciones han disminuido debido a la sobrepesca y otras intervenciones antrópicas. En este trabajo, se utilizaron loci microsatélites especie-específicos para contrastar la hipótesis de que las poblaciones de peces amenazadas muestran señales de vulnerabilidad genética y están genéticamente estructuradas en los sectores medio y bajo del río Cauca. Las especies estudiadas exhiben niveles de diversidad genética superiores a los promedios reportados para Siluriformes Neotropicales; sin embargo, parecen haber sufrido cuellos de botella recientes y presentan niveles significativos de endogamia que son más altos para el bagre en peligro crítico, P. grosskopfii. Además, Ageneiosus pardalis y S. cuspicaudus están conformados cada uno por un solo grupo genético, mientras que Pimelodus grosskopfii comprende dos grupos genéticos que coexisten. La información obtenida en este estudio es útil para la toma de decisiones en planes de manejo que sean adecuados para la sostenibilidad de las poblaciones de estas tres especies de bagre dentro de las propuestas para la expansión de desarrollo hidroeléctrico y otras actividades antrópicas.(AU)

Microsatellite loci development for three catfish species from northwestern South America

The Neotropical catfish species Ageneiosus pardalis, Pimelodus grosskopfii, and Sorubim cuspicaudus are important fishery resources in Colombia that show historical declines in their capture. This study used next-generation sequencing with 454 FLX technology (Roche Applied Science) and bioinformatics analysis to develop between 18 and 24 microsatellite loci for these species. The novel microsatellite loci showed high values of polymorphic information content -PIC (A. pardalis: 0.601-0.903, P. grosskopfii: 0.748-0.946 and S. cuspicaudus: 0.383-0.876), and the average number of alleles/locus ranged from 7-15 for A. pardalis, 9-30 for P. grosskopfii and 5-14 for S. cuspicaudus. The average observed and expected heterozygosities were respectively, 0.757 ± 0.035 and 0.834 ± 0.015 for A. pardalis; 0.596 ± 0.040 and 0.881 ± 0.009 for P. grosskopfii; and 0.747 ± 0.031 and 0.757 ± 0.025 for S. cuspicaudus. For future studies, these loci can be useful to estimate the genetic diversity and population structure in these three Neotropical catfishes.(AU)

Las especies de bagres neotropicales Ageneiosus pardalis, Pimelodus grosskopfii y Sorubim cuspicaudus, son importantes recursos pesqueros en Colombia y han mostrado disminuciones históricas en sus capturas. En este estudio se empleó la secuenciación genómica de próxima generación y análisis bioinformático para desarrollar entre 18 y 24 loci microsatélites para estas especies. Los loci microsatélites mostraron altos valores del contenido de información polimórfica CIP (A. pardalis: 0.601-0.903, P. grosskopfii: 0.748-0.946 and S. cuspicaudus: 0.383-0.876) y el número promedio de alelos/locus mostró un rango de 7-15 para A. pardalis, 9-30 para P. grosskopfii y 5-14 para S. cuspicaudus. Los valores promedio de heterocigosidad observada y esperada fueron respectivamente 0.757 ± 0.035 y 0.834 ± 0.015 para A. pardalis; 0.596 ± 0.040 y 0.881 ± 0.009 para P. grosskopfii; y 0.747 ± 0.031y 0.757 ± 0.025 para S. cuspicaudus. Los loci microsatélites desarrollados en este trabajo pueden ser útiles para estimar la diversidad genética y la estructura poblacional de estos tres bagres neotropicales en estudios futuros.(AU)

Shell shape variation of queen conch Strombus gigas (Mesograstropoda: Strombidae) from Southwest Caribbean / Variación de la conformación de la concha del caracol reina Strombus gigas (Caenogastropoda: Strombidae) del Caribe suroccidental

Abstract:The endangered species Strombus gigas is a marine gastropod of significant economic importance through the Greater Caribbean region. In contrast to phenotypic plasticity, the role of genetics on shell variations in S. gigas has not been addressed so far, despite its importance in evolution, management and conservation of this species. This work used geometric morphometrics to investigate the phenotypic variation of 219 shells of S. gigas from eight sites of the Colombian Southwest Caribbean. Differences in mean size between sexes and among sites were contrasted by analysis of variance. Allometry was tested by multivariate regression and the hypothesis of common slope was contrasted by covariance multivariate analysis. Differences in the shell shape among sites were analyzed by principal component analysis. Sexual size dimorphism was not significant, whereas sexual shape dimorphism was significant and variable across sites. Differences in the shell shape among sites were concordant with genetic differences based on microsatellite data, supporting its genetic background. Besides, differences in the shell shape between populations genetically similar suggest a role of phenotypic plasticity in the morphometric variation of the shell shape. These outcomes evidence the role of genetic back- ground and phenotypic plasticity in the shell shape of S. gigas. Thus, geometric morphometrics of shell shape may constitute a complementary tool to explore the genetic diversity of this species. Rev. Biol. Trop. 64 (4): 1585-1595. Epub 2016 December 01.

Resumen:La especie en peligro, Strombus gigas, es un gastrópodo marino de importancia económica en la región del Gran Caribe. En contraste con la plasticidad fenotípica, el papel de la genética en la variación de la concha en S. gigas no ha sido abordado hasta ahora, a pesar de su importancia evolutiva, manejo y conservación. Este trabajo utilizó la morfometría geométrica para investigar la variación fenotípica de la concha de S.gigas en ocho sitios del suroeste del Caribe colombiano. Las diferencias en el tamaño promedio entre sexos y sitios se contrastaron mediante análisis de varianza. La alometría se evaluó mediante regresión multivariada y la hipótesis de pendientes similares se contrastó mediante un análisis multivariado de covarianza. Las diferencias en la conformación de las conchas entre sitios se exploraron mediante análisis de componentes principales. El dimorfismo sexual en el tamaño no fue significativo, mientras que el dimorfismo sexual en la conformación fue significativo y variable entre los sitios. Las diferencias en la conformación de la concha entre sitios fueron concordantes con diferencias genéticas basadas en microsatélites, lo cual apoya su base genética. Además, las diferencias en conformación de la concha entre poblaciones genéticamente similares sugieren un papel de la plasticidad fenotípica en la variación morfométrica de la conformación de la concha. Estos resultados evidencian el papel de la genética y la plasticidad fenotípica en la conformación de la concha de S. gigas. Por lo tanto, la morfometría geométrica de la conformación de la concha puede constituir una herramienta complementaria para explorar la diversidad genética de esta especie.

Shell shape variation of queen conch Strombus gigas (Mesograstropoda: Strombidae) from Southwest Caribbean.

The endangered species Strombus gigas is a marine gastropod of significant economic importance through the Greater Caribbean region. In contrast to phenotypic plasticity, the role of genetics on shell variations in S. gigas has not been addressed so far, despite its importance in evolution, management and conservation of this species. This work used geometric morphometrics to investigate the phenotypic variation of 219 shells of S. gigas from eight sites of the Colombian Southwest Caribbean. Differences in mean size between sexes and among sites were contrasted by analysis of variance. Allometry was tested by multivariate regression and the hypothesis of common slope was contrasted by covariance multivariate analysis. Differences in the shell shape among sites were analyzed by principal component analysis. Sexual size dimorphism was not significant, whereas sexual shape dimorphism was significant and variable across sites. Differences in the shell shape among sites were concordant with genetic differences based on microsatellite data, supporting its genetic background. Besides, differences in the shell shape between populations genetically similar suggest a role of phenotypic plasticity in the morphometric variation of the shell shape. These outcomes evidence the role of genetic background and phenotypic plasticity in the shell shape of S. gigas. Thus, geometric morphometrics of shell shape may constitute a complementary tool to explore the genetic diversity of this species.

Mitochondrial genome of the Neotropical catfish Ageneiosus pardalis, Lütken 1874 (Siluriformes, Auchenipteridae).

Ageneiosus pardalis is a trans-Andean member of the Neotropical freshwater fish family Auchenipteridae (Siluriformes). In this work, the complete mitochondrial genome of A. pardalis was pyrosequenced by FLX 454 technology. The mitochondrial genome is 16,484 bp in length and encodes 13 proteins, 22 tRNAs and 2 ribosomal RNAs. Additionally, the synteny is conserved with others species of the Auchenipteridae family as well as other Siluriformes.

Mitochondrial genome of the Trans-Andean shovelnose catfish Sorubim cuspicaudus (Siluriformes, Pimelodidae).

The Trans-Andean shovelnose catfish Sorubim cuspicaudus is the largest species within the genus Sorubim. In this work, the pyrosequencing technology was used to obtain the complete mitochondrial genome sequence of S. cuspicaudus. The 16,544 bp molecule contains 13 protein-coding genes, 22 tRNAs, 2 ribosomal RNAs and exhibit perfect synteny with other South-American catfishes.