<![CDATA[An antioxidant flavonol glycoside isoquercitrin (0.01% w/w) from white petals of Mussaenda frondosa L flowers has been isolated in form of amorf yelowish powder, m.p. 288-230 oC. The structure was established from data of chromatography, UV-Vis spectra with shift reagents, infrared as well as the analysis of spectral data of 1H and 13C NMR. Antioxidant activity was performed by inhibition of radical scavenger of 2,2-difenil-1-pikrilhidrazil (DPPH) 50mM and the compound showed a high persentage inhibition of 93.97% compared to quersetin (92.92%). The compound was first reported from white petal of Mussaenda frondosa L.  ABSTRAK Antioksidan isokuersitrin (0,01% b/b) telah diisolasi dari kelopak putih bunga Nusaindah (Mussaenda frondosa L.), berupa amorf berwarna kuning dengan jarak leleh 228-230°C. Struktur senyawa ini ditetapkan berdasarkan (pola) kromatografi, spektrofotometer ultraviolet dengan berbagai pereaksi geser, spektrum inframerah serta analisis spektrum RMI (1H dan 13C). Pemeriksaan aktivitas antioksidan dilakukan dengan metode DPPH (radikal 2,2-difenil-1-pikrilhidrazil) 50mM dan senyawa (1) memiliki persentase inhibisi sebesar 93,97% sebanding dengan kuersetin (92,29%). Senyawa ini baru pertama dilaporkan dari kelopak putih bunga Mussaenda frondosa L]]>
Copyrights © 2010
