Influência de fatores edáficos na composição química de cascas e sementes de jabuticaba (Myrciaria cauliflora)

• Autor(a) principal: Pereira, Luciane Dias
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6011
• topic: Myrciaria cauliflora; Jabuticaba; Elucidação estrutural; Flavonoides; Antocianinas; Myrciaria cauliflora; Jaboticaba; Structural elucidation; Flavonoids; Anthocyanins; QUIMICA ORGANICA::QUIMICA DOS PRODUTOS NATURAIS

Seeds and peels of jabuticaba (Myrciaria cauliflora (Mart) O. Berg) collected in the Jabuticabal Winery were separately extracted with aqueous acetone (50%). After partitioning between solvents, the fractions ethyl acetate and methanol were subjected to repeated column chromatography using Diaion HP-20 and Sephadex LH-20 as adsorbents. Pure substances and fractions were analyzed by 1H NMR and 13C, one and two dimensional, and ESI-TOF mass spectroscopy. In this work, fifteen compounds were isolated and identified: seven ellagitannins, one of them is novel, one galloyl ester, three phenolic acids, two glycosylated flavonoids, one depside and one organic acid. To optimize the extraction of phenolic compounds, a randomized experimental design was applied, using Box-Wilson central composite design for two factors. The independent variables were stirring time () and solvent volume (V), which consisted of ethanol/hydrochloric acid (9:1). Three independent experiments in duplicate were performed, as well as assays for quantitation of phenolic compounds total monomeric anthocyanins (TMA), tannins (T), total phenols (TP), and color parameters color index (CI) and tonality (Ton). According to the results, when the volume remained constant and the stirring time increased, all phenolic contents and color patterns intensified. The best conditions for greater extraction were total ultrasonic time of 75 min and solvent volume of 64 ml, yielding the concentrations of TP, T and TMA of 33.5; 7.9 and 5.57 mg g-1, and CI and Ton, 0.893 a.u. and 0.833, respectively. In the extraction of phenolic compounds from seeds, the following solvents were tested water, aqueous ethanol (50%), aqueous methanol (50%), and the latter mixture provided the highest levels of TP, T and flavonoids: 15.71; 12.65 and 64.14 mg g-1, respectively. The influence of soil on jabuticaba seed and peel chemical contents was evaluated. Data obtained from the analysis of centesimal composition, phenolic contents, color parameters and mineral nutrients of samples collected in five orchards were analyzed by canonical redundancy (RDA) and hierarchical clustering (HCA). These analyzes ordered samples in four groups: the peels in groups I and II were related to high levels of phenolics and fibers, respectively, while the tannins and flavonoids were main compounds present in the seeds of group III, the moisture content was higher in seeds of group IV. The separation of peels (Groups I and II) and seeds (Groups III and IV) in different groups was influenced by the levels of fruits nutrients, Mn2+ and Cu2+, whereas Mn2+ from soil distinguished samples of the clusters I and III from the others, II and IV, characterizing a strong influence of some soil and fruits nutrients on the chemical composition of the jabuticaba seeds and peels.