Evalution of phenolic compounds in Brazilian propolis from different geographic regions

Chemometrics has been shown quite efficient to uncover relationships betwee n chemical composition of a sample and its geographical origin. Forty propo lis samples originated from the the South and South East of Brazil were ana lyzed by HPLC and 18 compounds of interest were studied which included: caf feic, p-coumaric and ferulic acids, and some of their derivatives, pinobank sin, a derivative of kaempferol and five phenolic compounds (assigned as 3- prenyl-4-hydroxycinnamic acid (PHCA); 2,2-dimethyl-6-carboxyethnyl-2H-1-ben zopyran (DCBE); 3,5-diprenyl-4-hydroxycinnamic acid (DHCA); compound E (sti ll unknown) and 6-propenoic-2,2-dimethyl-8-prenyl-2H-1-benzopyran acid (DPB ). Principal Component Analysis (PCA) indicated three different groups of p ropolis samples, having the same typical chromatogram evaluated by HPLC. Sa mples from the South East group were rich in derivatives of kaempferol. Sam ples from the South group I had a high content of DPB compound, but a low c oncentration of kaempferol derivatives and of DCBEN compound. Samples from the South group II were characterized by a high concentration of DCBEN, DHC A, p-coumaric and DPB compounds. Therefore, the identification of new compo unds in Brazilian propolis can give useful information about the plant sour ces of a given geographic region.