%0 Journal Article %T Platelet-Activating Factor (PAF) Antagonistic Activity of a New Biflavonoid from Garcinia nervosa var. pubescens King %A Juriyati Jalil %A Ibrahim Jantan %A Azura Abdul Ghani %A Shahnaz Murad %J Molecules %D 2012 %I MDPI AG %R 10.3390/molecules170910893 %X The methanol extract of the leaves of Garcinia nervosa var. pubescens King, which showed strong inhibitory effects on platelet-activating factor (PAF) receptor binding, was subjected to bioassay-guided isolation to obtain a new biflavonoid, II-3,I-5, II-5,II-7,I-4',II-4'-hexahydroxy-(I-3,II-8)-flavonylflavanonol together with two known flavonoids, 6-methyl-4'-methoxyflavone and acacetin. The structures of the compounds were elucidated by spectroscopic methods. The compounds were evaluated for their ability to inhibit PAF receptor binding to rabbit platelets using 3H-PAF as a ligand. The biflavonoid and acacetin showed strong inhibition with IC50 values of 28.0 and 20.4 ¦ÌM, respectively. The results suggest that these compounds could be responsible for the strong PAF antagonistic activity of the plant. %K Garcinia nervosa var. pubescens %K biflavonoid %K platelet-activating factor (PAF) antagonists %K platelets %U http://www.mdpi.com/1420-3049/17/9/10893