Coffea arabica instant coffee--chemical view and immunomodulating properties.

Results of chemical analyses and immunological studies of two Coffea arabica instant coffee powders obtained by freeze-dried (ICPf) and spray-dried (ICPs) procedures, and arabinogalactan-protein (AGP3) obtained from ICPf are presented. For instant coffee powders no significant differences have been found in carbohydrate (ICPf: 37%, ICPs: 38%) as well as in caffeine (ICPf: 3.0%, ICPs: 3.4%) contents. Their (1)H NMR spectra revealed differences in trigonelline and chlorogenic acids content and in a degree of AGP backbone substitution. Immunobiological tests of all samples (ICPf, ICPs, AGP2 and AGP3) revealed a significant immunostimulatory effect on induction of interleukin 2 and free radicals secretion by mice immunocytes. Moreover, tests revealed more pronounced effect of arabinogalactans AGP2 and AGP3 compared to instant coffee powders (ICPf and ICPs).