Navegando por Autor "Benassi, Marta T."

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Composition of Coffea canephora Varieties from the Western Amazon
(Sociedade Brasileira de Química, 2024-04-05) Acre, Lucas B.; Viencz, Thayna; Francisco, Julyene S.; Rocha, Rodrigo B.; Alves, Enrique A.; Benassi, Marta T.
This research aimed to compare the composition profiles of roasted Coffea canephora varieties (conilon, robusta, and intervarietal hybrids) grown in the Western Amazon. Ten coffees of each variety were evaluated. No difference in the contents of caffeine (1427 to 3364 mg 100 g 1) and kahweol (absence to 25.7 mg 100 g 1) was observed. Hybrid coffees were discriminated from traditional varieties (conilon and robusta) and stood out for their higher content of trigonelline, chlorogenic acids, and total diterpenes (mean values of 613,3791, and 471 mg 100 g 1, respectively), higher cafestol/kahweol ratio (7.6 to 15.0), and higher frequency of kahweol presence. Traditional varieties only differed in cafestol and 16-O-methylcafestol contents. Robusta coffees stood out for their lower cafestol content (116 mg 100 g 1), and conilon for their lower 16-O-methylcafestol content (139 mg 100 g 1). Differences between the traditional varieties are smaller than that observed among them and the intervarietal hybrid coffees.
DETERMINISMO GENÉTICO E MOLECULAR DO METABOLISMO DE DITERPENOS EM Coffea spp.
(2009) Ferreira, Lucia P.; Dias, Rafael Ce.; Durand, Noel; Guyot, Bernard; Ramos, Juliana; Perthuis, B.; Sandrin-Garcia, Paula; Benassi, Marta T.; Marraccini, Pierre; Pereira, Luiz Fp.; Leroy, Thierry; Vieira, Luiz Ge.; Pot, David; Embrapa - Café
Cafestol e caveol são os dois principais diterpenos presentes nos frutos de café. Esses compostos específicos do cafeeiro têm se mostrado importantes na saúde humana, induzindo alterações no colesterol e ações anti- cancerígenas. Apesar da sua importância, há pouca informação sobre os princípios genéticos e moleculares de seu metabolismo. Análises fenotípicas através de HPLC, com cafés de diferentes espécies (vários genótipos por espécie), indicam uma variabilidade importante para cafestol, caveol e 16OMC. As análises in silico dos EST de Coffea permitiram identificar cDNAs parciais correspondente a um gene de CPS, dois de KO e um de KS. Análises de expressão desses genes por RTq-PCR quantitativa, em tecidos separados durante o desenvolvimento dos frutos, estão em andamento. Resultados preliminares indicam que os quatro genes alvos apresentam expressão diferencial durante o desenvolvimento dos tecidos do fruto. Os resultados de expressão serão discutidos considerando o interesse na identificação dos genes potencialmente envolvidos na regulação da concentração de cafestol e caveol.
Discrimination of commercial roasted and ground coffees according to chemical composition
(Sociedade Brasileira de Química, 2012) Souza, Romilaine M. N. de; Benassi, Marta T.
Roasted and ground 38 commercial coffees and coffees of known species (arabica, robusta) were characterized by principal component analysis using as variables nicotinic acid, trigonelline, 5-o-caffeoylquinic acid (5-CQA), caffeine, kahweol and cafestol, which are potentially indicative of species. The objective of the study was to assess the relevance of such parameters in coffee discrimination. Nicotinic acid allowed the characterization of roasting degree. Trigonelline and 5-CQA presented variability among arabica and robusta coffees as well as among comercial ones. Thermostable parameters (caffeine, kahweol and cafestol) had high discriminative potential between the species. In general, high levels of caffeine and low levels of diterpenes (kahweol and cafestol) were related with higher proportions of robusta in the products, which were observed by the decreasing kahweol/cafestol ratio and increasing caffeine/kahweol ratio. The use of these new parameters (kahweol/cafestol and caffeine/kahweol ratios) was suggested as tools for assessing the addition of robusta in commercial coffees.