@article {218, title = {Quantitative Phytochemical Constituents and Antioxidant Activities of the Mistletoe, Phragmanthera capitata (Sprengel) Balle Extracted with Different Solvents}, journal = {Pharmacognosy Research}, volume = {10}, year = {2018}, month = {February 2018}, pages = {16-23}, type = {Original Article}, chapter = {16}, abstract = {

Objective: The investigation aimed to evaluate the in vitro quantitative phytochemical compositions and antioxidant capacity of the dried leaves of Phragmanthera capitata extracted with different solvents. Methodology: Different phytochemical assays were used to evaluate the phenols, flavonoids, and proanthocyanidin contents of the acetone, methanol, ethanol, and aqueous extracts of the sample. Antioxidant activity was measured using 2,2diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), Ferric reducing antioxidant power (FRAP), nitric oxide, and total antioxidant capacity (TAC) assays. Results: Methanol had the highest extraction yield (21.50\%) followed by aqueous (10.87\%). Acetone and ethanol yielded 6.87\% and 4.3\%, respectively. However, acetone and ethanol extracts had more phenolic content (218.6 {\textpm} 3.38 and 214.8 {\textpm} 3.56 mg gallic acid equivalent (GAE)/g, respectively) that were significantly higher (P \< 0.05) than the methanol and aqueous extracts (203.8 {\textpm} 1.95 and 175.5 {\textpm} 0.32 mg GAE/mg, respectively). Acetone extract also had more flavonoid and proanthocyanidin contents (679.8 {\textpm} 6.26 mg quercetin equivalent/g and 645.7 {\textpm} 6.35 mg catechin equivalent/g, respectively) that were significantly higher than the other solvent extracts (P \< 0.05). All the solvent fractions showed great antioxidant activities with the acetone fraction having the highest capacity based on ABTS, DPPH, and TAC assays (half maximal inhibitory concentration [IC50] = \<5 {\textmu}g/ mL, 24.5 {\textmu}g/mL, and 85 {\textmu}g/mL respectively). The methanol extract however had FRAP and nitric oxide antioxidant activities (IC50 = 302 {\textmu}g/ mL and \<25 {\textmu}g/mL respectively). Conclusion: The findings of this study provide evidence that P. capitata has potential as a natural source of antioxidant with acetone showing to be the best extractant of the polyphenolics with corresponding higher antioxidant activities.

}, keywords = {Extractant, Loranthaceae, Mistletoe, Phragmanthera capitata, Polyphenolics, Total antioxidant activity}, doi = {10.4103/pr.pr_65_17}, author = {Franklin Uangbaoje Ohikhena and Olubunmi Abosede Wintola and Anthony Jide Afolayan} } @article {543, title = {Chemical constituents of Phragmanthera austroarabica A. G. Mill and J. A. Nyberg with potent antioxidant activity}, journal = {Pharmacognosy Research}, volume = {7}, year = {2015}, month = {October 2015}, pages = {335-340}, type = {Original Article}, chapter = {335}, abstract = {

Background: Phragmanthera austroarabica A.G. Mill. and J. A. Nyberg is a semi parasitic plant belonging to family Loranthaceae. It was collected from Saudi Arabia. It is widely used in folk medicine among the kingdom in treatment of various diseases including diabetes mellitus. Objectives: The total alcoholic extract of P. austroarabica collected from Saudi Arabia was investigated for the chemical structure and prominent biological activity of the main constituents. Materials and Methods: Isolation of the active constituents was performed using different chromatographic techniques including column chromatography packed with silica or sephadex and preparative thin layer chromatography. The structures of the isolated compounds were established based on different spectroscopic data as mass spectrum, one-dimensional and two-dimensional nuclear magnetic resonance (correlation spectroscopy,
heteronuclear single quantum coherence, and heteronuclear multiple-bond correlation). Results: Phytochemical investigation of the plant resulted in isolation of 12 compounds. The isolated compounds were identified as chrysophanic acid, emodin, chrysophanic acid-8-O-glucoside, emodin-8-O-glucoside, pectolinarigenin, quercetin, dillenetin-3-O-glucoside, catechin, catechin-4{\textquoteright}-O-gallate, methyl gallate, lupeol and ursolic acid. All the isolated phenolic compounds revealed significant free radical scavenging activities when tested using 2,2-diphenyl-1-picrylhydrazyl reagent. Conclusion: The antioxidant activities of the isolated compounds can justify the use of P. austroarabica in traditional medicine for treatment of diabetes and verify its possible application as an antihyperglycemic drug.

}, keywords = {Antioxidant, Loranthaceae, Nuclear magnetic resonance, Phragmanthera.}, doi = {10.4103/0974-8490.158436}, author = {Jihan M. Badr} }