Spectrophotometric Quantification of Flavonoids in Herbal Material, Crude Extract, and Fractions from Leaves of Eugenia uniflora Linn

• Published in: Pharmacognosy research Vol. 9; no. 3; pp. 253 - 260
• Main Authors: Ramos, Rhayanne T M, Bezerra, Isabelle C F, Ferreira, Magda R A, Soares, Luiz Alberto Lira
• Format: Journal Article
• Language: English
• Published: India Medknow Publications and Media Pvt. Ltd 01.07.2017; Phcog.net; Medknow Publications & Media Pvt Ltd
• Subjects: Aluminum; Aluminum compounds; Diabetes; Ethanol; Flavonoids; Herbal medicine; Isoflavones; Laboratories; Metabolites; Methods; Oils & fats; Original; Pharmaceutical sciences; Brazil; ultraviolet-visible; fractions; total flavonoids content; Eugenia uniflora L; validation
• ISSN: 0976-4836; 0974-8490; 0974-8490
• DOI: 10.4103/pr.pr_143_16

The traditional use of L. ("Pitanga") is reported due to several properties, which have often been related to its flavonoid content. The aim was to evaluate analytical procedures for quantification of total flavonoids content (TFCs) by ultraviolet-visible (UV-Vis) spectrophotometry in the herbal material (HM), crude extract (CE), and fractions from leaves of . The method for quantification of flavonoids after complexation with aluminum chloride (AlCl ) was evaluated: amount of sample (0.25-1.5 g); solvent (40%-80% ethanol); reaction time and AlCl concentration (2.5%-7.5%). The procedures by direct dilution (DD) and after acid hydrolysis (AH) were used and validated for HM and CE and applied to the aqueous fraction (AqF), hexane fraction, and ethyl acetate fractions (EAF). The ideal conditions of analysis were ethanol 80% as solvent; 0.5 g of sample; λmax of 408 (DD) and 425 nm (AH); 25 min after addition of AlCl 5%. The procedures validated for standards and samples showed linearity ( > 0.99) with limit of detection and limit of quantification between 0.01 and 0.17 mg/mL (rutin and quercetin); and 0.03 and 0.09 mg/mL (quercetin), for DD and AH, respectively. The procedures were accurate (detect, practice, and repair < 5% and recovery >90%), and stable under robustness conditions (luminosity, storage, reagents, and equipment). The TFCs in AqF and EAF were 0.65 g% and 17.72 g%, calculated as rutin. UV-Vis methods for quantification of TFC in HM, CE, and fractions from leaves of were suitably validated. Regarding the analysis of fractions, the EAF achieved enrichment of about nine times in the content of flavonoids. The total flavonoids content (TFCs) of herbal material, crude extract, and fractions from can be quantified by ultraviolet-visibleThe spectrophotometric methods (direct dilution and acid hydrolysis) were reproducible and able to quantify TFC in raw material and derivatives from leaves of Higher flavonoids content was observed in ethyl acetate fractions after enrichment. : HM: Herbal material, CE: Crude extract, AqF: Aqueous fraction, HF: Hexanic fraction, EAF: Ethyl acetate fraction, TFC: Total flavonoids content, HCl: Hydrochloric acid, DD: Direct dilution, AH: After hydrolysis, RSD: Relative standard, A.U.: Absorption units.