... propenoic acid 1.2.2 Tớnh cht húa lý Acid p- coumaric l mt acid hydroxyl cinnamic, l hp cht hu c m nhúm OH c gn vo acid cinnamic Acid coumaric cú ng phõn: acid o -coumaric, acid m -coumaric v acid p- coumaric, ... 12 2.3 Phng ph p nghiờn cu 12 2.3.1 Xõy dng v thm nh phng ph p nh lng acid p- coumaric thõn cõy í d bng HPLC 12 2.3.2 p dng phng ph p ó c xõy dng xỏc nh hm lng acid p- coumaric ... dng v thm nh phng ph p nh lng acid p- coumaric thõn cõy í d bng sc kớ lng hiu nng cao (HPLC) - p dng phng ph p ó c xõy dng xỏc nh hm lng acid pcoumaric cỏc mu thõn cõy í d 2.3 Phng ph p nghiờn cu...