Treatment with the water and tropical lemon juice extract powders from acerola fruit purees and leaves (100 mg/kg) significantly ameliorates the hepatic inflammatory responses such as increased serum levels of AST, ALT, and GGT in rats subjected to acute D-galactosamine (GalN) intoxication. The protective effects of their constituents could be related to their antioxidant activities to neutralise free radicals to attenuate hepatic lipid peroxidation and thus can protect liver damage. The effect of the water extract powder from fruit purees (100 mg/kg) was moderately stronger than that of ascorbic acid (10 mg/kg), but weaker than that of cyanidin-3-O-rhamnoglucoside (13.3 mg/kg). The water and lemon juice extract powders from Acerola fruit purees possess the 18.6 and 24.1-fold higher DPPH radical scavenging activities, respectively, than those from leaves, the higher so for those extracted with lemon juice than for those extracted with water. The vitamin C contents were much more higher in the extract powders from fruit purees compared with those from leaves. γ-Tocopherol predominated in the extract powders from fruit purees and α-tocopherol in those from leaves. Polyphenolic compounds were identified and analysed by GC/MS-SIM after acid hydrolysis, extraction and derivatisation to trimethylsilyl ethers.