Phenolic Composition of the Leaves of Pyrola rotundifolia L. and Their Antioxidant and Cytotoxic Activity

Abstract

The leaves of Pyrola rotundifolia L. were extracted in the mixed solvent of methanol/acetone/water (2:2:1, v/v/v) and investigated for their phytochemical analysis and biological activity. Total phenolic and flavonoid contents were determined spectrophotometrically. A high content of phenols (208.35 mg GAE/g of dry extract), flavonoids (38.90 mg QE/g of dry extract) and gallotannins (722.91 GAE/g of dry extract) was obtained. Ultra-high performance liquid chromatography diode array detector tandem mass spectrometry (UHPLC–DAD–MS) allowed for the detection of 23 major peaks at 254 nm. The extract was analyzed for its antioxidant capacity using 2,2-diphenyl-1-picryl-hydrazyl (DPPH•) and 2,2′-azinobis[3-ethylbenzthiazoline]-6-sulfonic acid (ABTS•+) radical scavenging, metal chelating power and β-carotene-linoleic acid bleaching assays. The examined extract showed moderate radical scavenging and chelating activity, and good inhibiting ability of linoleic acid oxidation (EC50 = 0.05 mg/mL) in comparison to standards. The cytotoxic effect in increasing concentration on five types of leukemic cell lines was also investigated using trypan blue vital staining. It was found that the analyzed extract induced the apoptosis of all the tested cell lines. Our findings suggest that the leaves of P. rotundifolia are a source of valuable compounds providing protection against oxidative damage, hence their use in traditional medicine is justified.

Extracts from Cephalaria Uralensis (Murray) Roem. & Schult. and Cephalaria Gigantea (Ledeb.) Bobrov as Potential Agents for Treatment of Acne Vulgaris: Chemical Characterization and In Vitro Biological Evaluation

“…The plant materials were dried in shade and at 26 • C (±0.5 • C) until constant weight [31]. Extracts were prepared using 80% acetone (3 × 300 mL), mixture of methanol-acetone-water (3:1:1, v/v/v; 3 × 300 mL) and 30% ethanol (1 × 300 mL) [32]. With acetone and mixture of methanol-acetone-water, plant materials were sonicated at controlled temperature (40 ± 2 • C) for 30 min, and with ethanol were shaken at room temperature for 24 h. The combined extracts were filtered, concentrated under reduced pressure, and after freezing, lyophilized in a vacuum concentrator (Free Zone 1 apparatus; Labconco, Kansas City, KS, USA) to obtain dried residues.…”

“…The second method used was 2,2 -azinobis[3-ethylbenzthiazoline]-6-sulfonic acid (ABTS •+ ) decolorization assay [32]. The absorbance was measured at 734 nm.…”

“…The metal chelating activity was determined using the method described by Guo et al [33], modified in our previous study [32]. The absorbance was measured at 562 nm.…”

Phenolic Composition and Skin-related Properties of the Aerial Parts Extract of Different Hemerocallis Cultivars

“…Total flavonoid (TFC) and total phenolic content (TPC) were established using the colorimetric assays as described previously [39]. The absorbance was measured at 430 and 680 nm, respectively, using Pro 200F Elisa Reader (Tecan Group Ltd., Männedorf, Switzerland).…”

“…kwanso Regel, H2-H. "Aten", H3-H. "Bożena", H4-H. "Catherine Woodbuery", H5-H. "Chicago Apache", H6-H. "Danuta", H7-H. "Jaskółka", H8-H. "Rebel Cause"; DE-Dry extract. The total flavonoid content of the flowering aerial parts of Hemerocallis cultivars was estimated by previously described colorimetric method [39] and was expressed as quercetin equivalents (QE) per g of dry extracts. The results presented in Table 1 show that among studied species, a significantly higher content of total flavonoids was observed for H. "Chicago Apache" (H5) and H. fulva var.…”