Molecules · 2019 · 59 citations · 31 references
Life SciencesBotanyPlant SciencesEthnobotanyPlant BiochemistryPlant PhysiologyFood AntioxidantsMedicinal PlantsPhenolic Compound AnalysisAntioxidant Activity AssaysAntioxidant Capacity AssaysCytotoxicity AssaysExtraction SolventsPhenolic Compound ExtractionPhenolic CompoundsPhenolic Content AnalysisPlant Extract Antioxidants
This experiment was conducted with extracts prepared from dandelion (Taraxacum officinale F. H. Wigg) leaves and flowers, using the micelle-mediated extraction method, with the surface active compound Triton X-100 and water–acetone as the extraction solvents. Extracts were, first, examined for the content of total phenols and the antioxidant capacity. All extracts showed good anti-radical properties, especially for leaves, in comparison to the flower samples. Flavonoids (mainly luteolin derivatives) and phenolic acids, predominated among the determined polyphenols. Quantitative analyses indicated acetone extract to be the richest in phenols (up to 0.535 mg/mL), in the case of dandelion leaves, and Triton X-100 extract in the case of flowers (0.385 mg/mL). Extracts were also evaluated for cytotoxicity to the model cell line (epithelial rabbit kidney cells RK13), using the colorimetric 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test and the real-time cell analysis method ((RTCA); xCELLigence system). The obtained results indicated that surfactants, especially non-ionic ones, can be effectively used as modifiers in the aqueous extraction of phenolic compounds from plant materials. An advantage over the traditional organic solvents is their non-flammability. Furthermore, surfactants might also be used at low concentrations. Studies on cell lines, however, indicated the cytotoxic effect of this type of compound, even in the trace amounts present in the extracts.
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Use of a free radical method to evaluate antioxidant activity
Wendy Brand-Williams, Marie‐Elisabeth Cuvelier, Claudette Berset · LWT · 1995 · 25.2K citations · Full text
Reşat Apak, Kubilay Güçlü, Mustafa Özyürek et al. · Journal of Agricultural and Food Chemistry · 2004 · 2.7K citations