SADDAM M.ABED; ISMAEAL KH. IBRAHIM
Abstract
The spectrophotomatric spectra in UV, Visible and IR regions have revealed the presence of many functional groups in the aqueous and ethanolic extracts of Hibiscus sabdariffa L. flowers ...
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The spectrophotomatric spectra in UV, Visible and IR regions have revealed the presence of many functional groups in the aqueous and ethanolic extracts of Hibiscus sabdariffa L. flowers .Paper, thin-layer and column chromatographic techniques have shown the presence of three pigments in both extracts ; Gossypetin, Anthocynin, and Querectin .Five organic acids were also separated and identified in both extracts .All these compounds were identified by UV, Visible and IR spectrophotomatry of electromagnetic radiation .Flame atomic absorption and emission technique haveoffered high levels of determination of calcium, barium, potassium and magnesium, while sodium, lithium, iron, manganese, copper, zinc and nickel were found in traces .pH and potential titrations of the extracts with standardized NaOH have shown high inflections at equivalence points which were exploited in the determination of total acids in the extract which was more than 28% .The sudden colour change from violet, red or pinkish of the extract into green has led us to exploit the extracts as an acid-base indicator . The data and results obtained have clarified that the extracts of Hibiscus sabdariffa L. flowers are matching the action of other indicators used in acid-base titrations
