controlled study unclassified drug Article Cells, Cultured human Calophyllum Humans IC50 animal cell article bark cell culture cell viability coumarin derivative drug isolation drug structure friedelin glyceraldehyde 3 phosphate dehydrogenase human cell in vitro study nonhuman protein expression reverse transcription polymerase chain reaction 1,3,7 trihydroxy 2,4 bis(3 methyl 2 butenyl)xanthone 2D gel electrophoresis 5,7 dihydroxy 6 (2 methybutyryl) 4 phenylcoumarin 5,7 dihydroxy 6 (3 methybutyryl) 4 phenylcoumarin ALDOA gene Adipocyte Adipogenesis