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Bonatto C.C.,University of Brasilia | Silva L.P.,Embrapa Recursos Geneticos e Biotecnologia
Journal of the Science of Food and Agriculture | Year: 2015

BACKGROUND: Chocolate authentication is a key aspect of quality control and safety. Matrix-assisted laser desorption ionization time-of flight (MALDI-TOF) mass spectrometry (MS) has been demonstrated to be useful for molecular profiling of cells, tissues, and even food. The present study evaluated if MALDI-TOF MS analysis on low molecular mass profile may classify chocolate samples according to the cocoa content. RESULTS: The molecular profiles of seven processed commercial chocolate samples were compared by using MALDI-TOF MS. Some ions detected exclusively in chocolate samples corresponded to the metabolites of cocoa or other constituents. This method showed the presence of three distinct clusters according to confectionery and sensorial features of the chocolates and was used to establish a mass spectra database. Also, novel chocolate samples were evaluated in order to check the validity of the method and to challenge the database created with the mass spectra of the primary samples. Thus, the method was shown to be reliable for clustering unknown samples into the main chocolate categories. CONCLUSION: Simple sample preparation of the MALDI-TOF MS approach described will allow the surveillance and monitoring of constituents during the molecular profiling of chocolates. © 2014 Society of Chemical Industry. Source

Pastore J.F.B.,Embrapa Recursos Geneticos e Biotecnologia
Phytotaxa | Year: 2014

This paper is a review of all Polygalaceae material on which the treatments of the family by Saint-Hilaire and Moquin- Tandon in 1828 and Saint-Hilaire in 1829 were based. It includes type designation for the names of all new taxa there proposed, except for Polygala paludosa var. ambigua. Some of the Saint-Hilaire and Moquin-Tandon's names which were omitted in several Neotropical Polygalaceous treatments are here reviewed. Therefore, one of them, Polygala sellowiana, is here re-established as the correct name for the species better known as P. sabulosa. More detailed information is provided for Saint-Hilaire's Polygalaceae collection. © 2014 Magnolia Press. Source

da Silva T.L.,University of Sao Paulo | Scherwinski-Pereira J.E.,Embrapa Recursos Geneticos e Biotecnologia
Pesquisa Agropecuaria Brasileira | Year: 2011

The objective of this work was to evaluate in vitro storage of Piper aduncum and P. hispidinervum under slow-growth conditions. Shoots were stored at low temperatures (10, 20 and 25°C), and the culture medium was supplemented with osmotic agents (sucrose and mannitol - at 1, 2 and 3%) and abiscisic acid - ABA (0, 0.5, 1.0, 2.0 and 3.0 mg L-1). After six-months of storage, shoots were evaluated for survival and regrowth. Low temperature at 20°C was effective for the in vitro conservation of P. aduncum and P. hispidinervum shoots. In vitro cultures maintained at 20°C on MS medium showed 100% survival with slow-growth shoots. The presence of mannitol or ABA, in the culture medium, negatively affected shoot growth, which is evidenced by the low rate of recovered shoots. Source

Pastore J.F.B.,Embrapa Recursos Geneticos e Biotecnologia
Phytotaxa | Year: 2013

Names of Polygalaceae used by Vellozo in his Flora Fluminensis are reviewed within the current floristic context of the State of Rio de Janeiro and its bordering areas, as well as the morphological evidence provided. Nearly all of Vellozo's names are placed as synonyms of older names, except for a new combination for Polygala disperma as Bredemeyera and Polygala appendiculata which is considered a valid name for P. leptocaulis. All names not yet typified are here lectotypified, except for B. autranii. © 2013 Magnolia Press. Source

Aragao F.J.L.,Embrapa Recursos Geneticos e Biotecnologia | Nogueira E.O.P.L.,Embrapa Recursos Geneticos e Biotecnologia | Tinoco M.L.P.,Embrapa Recursos Geneticos e Biotecnologia | Faria J.C.,Embrapa Arroz e Feijao
Journal of Biotechnology | Year: 2013

Golden mosaic of common bean is caused by the Bean golden mosaic virus (BGMV). The disease is one of the greatest constraints on bean production in Latin America and causes significant yield losses. The RNAi concept was explored to silence the rep (AC1) viral gene and a transgenic bean line immune to BGMV upon inoculation at high pressure was previously generated. Identification of the transgene insert confirmed the presence of a single locus corresponding to two intact copies of the RNAi cassette in opposite orientation and three intact copies of the AtAhas gene. It is flanked by Phaseolus genomic sequences and interspersed by one nuclear and three chloroplastic genomic sequences. Southern analyses showed that the transgenes were structurally stable for eight self-pollinated generations and after backcrosses with a non transgenic commercial variety. Transgene expression analyses revealed similar levels of siRNA in leaves of transgenic plants cultivated under field conditions in three distinct regions. siRNA were also analyzed during seed development in common bean transgenic plants. siRNA signals were also detected in seeds, albeit at significantly lower levels than those observed in leaves, and could not be detected in seeds cooked during 10. min. This information is relevant to demonstrate that GM beans are free of siRNA signals after cooking and therefore suitable for human consumption. Additionally, characterization of the locus where the transgene was integrated in the common bean genome provides a valuable tool to trace this GM bean material in the field and in the market. © 2013 Elsevier B.V. Source

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