Efecto de la liofilización en la retención de antocianinas de los frutos de calafate (Berberis microphylla G. Forst.) y su incorporación en cerveza

Los frutos de calafate son extremadamente ricos en compuestos antioxidantes, principalmente antocianinas. El objetivo fue evaluar la influencia de la liofilización sobre el contenido de antocianinas en los calafates durante el almacenamiento. Un grupo de frutos fue analizado inmediatamente y los restantes fueron sometidos a congelado a -80 ºC y liofilización. Por otra parte, a cerveza comercial tipo block se le adicionó 1,0; 2,5; 5,0 o 20 g L-1 de frutos liofilizados y pulverizados. Los frutos frescos tuvieron 35 mg g-1 de antocianinas y la liofilización redujo su contenido en 7 %. El contenido de antocianinas se mantuvo sin variaciones por 21 y 45 días respectivamente. Hacia los 60 días el contenido de antocianinas de los frutos liofilizados representó el 67% del contenido inicial. El pH de la cerveza fue de 4,34 y no varió con el agregado de polvo de calafate hasta 5 g L-1. En el caso de las cervezas con el agregado de 20 g L-1 el pH descendió a 4,00. El agregado de calafate provocó un cambio en el color de la cerveza debido a su aporte de antocianinas, y este cambio en el color fue función de la cantidad de fruto adicionado. La absorbancia a 520 nm fue de 0,230; 0,254; 0,291; 0,353 y 0,644 para la cerveza sin agregado o con 1,0; 2,5; 5,0 o 20 g L-1 de calafate  espectivamente. Solo cantidades mayores a 2,5 g L-1 de polvo adicionado provocaron un incremento de actividad antioxidante, llegando al 30 % con la adición de 20 g L-1. La liofilización es una estrategia adecuada para preservar las antocianinas de los frutos de calafate sin alteraciones por 45 días. Dependiendo de la cantidad adicionada, el calafate provoca en la cerveza cambio de color y descenso del pH que puede ser de utilidad en cervezas especiales

Validation of Genotyping by Sequencing Using Transcriptomics for Diversity and Application of Genomic Selection in Tetraploid Potato

Potato is an important food crop due to its increasing consumption, and as a result, there is demand for varieties with improved production. However, the current status of breeding for improved varieties is a long process which relies heavily on phenotypic evaluation and dated molecular techniques and has little emphasis on modern genotyping approaches. Evaluation and selection before a cultivar is commercialized typically takes 10–15 years. Molecular markers have been developed for disease and pest resistance, resulting in initial marker-assisted selection in breeding. This study has evaluated and implemented a high-throughput transcriptome sequencing method for dense marker discovery in potato for the application of genomic selection. An Australian relevant collection of commercial cultivars was selected, and identification and distribution of high quality SNPs were examined using standard bioinformatic pipelines and a custom approach for the prediction of allelic dosage. As a result, a large number of SNP markers were identified and filtered to generate a high-quality subset that was then combined with historic phenotypic data to assess the approach for genomic selection. Genomic selection potential was predicted for highly heritable traits and the approach demonstrated advantages over the previously used technologies in terms of markers identified as well as costs incurred. The high-quality SNP list also provided acceptable genome coverage which demonstrates its applicability for much larger future studies. This SNP list was also annotated to provide an indication of function and will serve as a resource for the community in future studies. Genome wide marker tools will provide significant benefits for potato breeding efforts and the application of genomic selection will greatly enhance genetic progress

Tecnología de la elaboración de quesos: experiencias de investigación aplicada y capacitación para estudiantes, técnicos, pequeños productores y la comunidad en general

Con un volumen de unos 11.300 millones de litros anuales, la Argentina es el segundo productor de leche de Latinoamérica, luego de Brasil. Los quesos constituyen el destino industrial más importante de la leche en nuestro país. Con los objetivos de 1) difundir los aspectos más salientes de los procesos de transformación de leche en productos elaborados para el público en general y 2) realizar aportes en la mejora de los procesos de producción de quesos para pequeños productores y técnicos del sector, hemos venido realizando en los últimos años diferentes actividades desde el Laboratorio de Investigación en Productos Agroindustriales (LIPA) de la Facultad de Ciencias Agrarias y Forestales de la Universidad Nacional de La Plata. Así, se organizaron talleres y cursos de capacitación para diferentes grupos: a) alumnos de educación inicial interesados en conocer los fundamentos del proceso de transformación de leche en queso, b) estudiantes de colegios secundarios agropecuarios con interés en profundizar en aspectos de calidad e industrialización de leche, c) estudiantes de la carrera de biotecnología de la UNLP con curiosidad por conocer cómo herramientas de interés desarrolladas biotecnológicamente (cuajo, cultivos iniciadores) son empleadas en la industria, d) pequeños productores y técnicos con interés de mejorar sus productos y servicios. Asimismo, en el laboratorio se llevan adelante investigaciones aplicadas tendientes a determinar la influencia de factores de proceso sobre la calidad y estabilidad de quesos. Algunos de los aspectos analizados incluyen la influencia del nivel de grasa de la leche sobre la calidad sensorial, composición de quesos, la optimización de la obtención de ricota a partir de leche, la influencia de la intensidad de lavado de la masa sobre las propiedades funcionales de queso cremoso. La combinación de investigación aplicada y actividades de capacitación y divulgación resulta una estrategia indispensable para poder transferir los conocimientos disponibles en las instituciones universitarias al medio así como para retroalimentar a la universidad con problemáticas reales y los saberes del sector productivo

Enzymatic capacities of metabolic fuel use in cuttlefish (Sepia officinalis) and responses to food deprivation: insight into the metabolic organization and starvation survival strategy of cephalopods

Food limitation is a common challenge for animals. Cephalopods are sensitive to starvation because of high metabolic rates and growth rates related to their "live fast, die young" life history. We investigated how enzymatic capacities of key metabolic pathways are modulated during starvation in the common cuttlefish (Sepia officinalis) to gain insight into the metabolic organization of cephalopods and their strategies for coping with food limitation. In particular, lipids have traditionally been considered unimportant fuels in cephalopods, yet, puzzlingly, many species (including cuttlefish) mobilize the lipid stores in their digestive gland during starvation. Using a comprehensive multi-tissue assay of enzymatic capacities for energy metabolism, we show that, during long-term starvation (12 days), glycolytic capacity for glucose use is decreased in cuttlefish tissues, while capacities for use of lipid-based fuels (fatty acids and ketone bodies) and amino acid fuels are retained or increased. Specifically, the capacity to use the ketone body acetoacetate as fuel is widespread across tissues and gill has a previously unrecognized capacity for fatty acid catabolism, albeit at low rates. The capacity for de novo glucose synthesis (gluconeogenesis), important for glucose homeostasis, likely is restricted to the digestive gland, contrary to previous reports of widespread gluconeogenesis among cephalopod tissues. Short-term starvation (3-5 days) had few effects on enzymatic capacities. Similar to vertebrates, lipid-based fuels, putatively mobilized from fat stores in the digestive gland, appear to be important energy sources for cephalopods, especially during starvation when glycolytic capacity is decreased perhaps to conserve available glucose

Guidelines for the reliable use of high throughput sequencing technologies to detect plant pathogens and pests

High-throughput sequencing (HTS) technologies have the potential to become one of the most significant advances in molecular diagnostics. Their use by researchers to detect and characterize plant pathogens and pests has been growing steadily for more than a decade and they are now envisioned as a routine diagnostic test to be deployed by plant pest diagnostics laboratories. Nevertheless, HTS technologies and downstream bioinformatics analysis of the generated datasets represent a complex process including many steps whose reliability must be ensured. The aim of the present guidelines is to provide recommendations for researchers and diagnosticians aiming to reliably use HTS technologies to detect plant pathogens and pests. These guidelines are generic and do not depend on the sequencing technology or platform. They cover all the adoption processes of HTS technologies from test selection to test validation as well as their routine implementation. A special emphasis is given to key elements to be considered: undertaking a risk analysis, designing sample panels for validation, using proper controls, evaluating performance criteria, confirming and interpreting results. These guidelines cover any HTS test used for the detection and identification of any plant pest (viroid, virus, bacteria, phytoplasma, fungi and fungus-like protists, nematodes, arthropods, plants) from any type of matrix. Overall, their adoption by diagnosticians and researchers should greatly improve the reliability of pathogens and pest diagnostics and foster the use of HTS technologies in plant health

Identification and characterization of banana bract mosaic virus in India

We have identified banana bract mosaic potyvirus (BBMV) in banana plants growing in the Coimbatore and Tiruchchirappalli regions of southern India based on symptomatology, particle morphology, sequence homology, and nucleic acid hybridization assays. Potyvirus-like particles typical of BBMV also were detected in sap dips from banana plants growing in Maharashtra State. Sequence comparisons of the C terminus of the coat protein-coding and 3' untranslated regions revealed that the Indian isolates of BBMV bad greater than 96.6 and 97.2% homology with a Philippines isolate at the nucleotide and amino acid levels, respectively. BBMV-infected banana cultivars from the Coimbatore region showed the characteristic mosaic on the bract of the banana inflorescence. In contrast, infected plants growing in the Tiruchchirappalli region and Maharashtra State displayed symptoms similar to those associated with cucumber mosaic cucumovirus and not the characteristic bract mosaic symptom. These results indicate that BBMV is more widespread than previously thought.</p