Cytotoxic, hepatoprotective and free radical scavenging effects of propolis from Brazil, Peru, the Netherlands and China

Propolis is a resinous hive product collected by honeybees from various pla nt sources. The composition of the propolis depends upon the time, vegetati on and the area of collection. Thus, quality evaluation of the propolis is important, before use in food and beverages. For this propose three differe nt biological activities were carried out, i.e. 1,1-diphenyl-2-picrylhydraz yl (DPPH) free radical scavenging activity, cytotoxicity and hepatoprotecti ve activity, of MeOH and water extracts of nine different propolis from Bra zil, Peru, the Netherlands and China. The results showed that water extract s of six Brazilian and a Chinese propolis possessed stronger DPPH free radi cal scavenging activity than the corresponding MeOH extract, whereas in the case of Netherlands and Peruvian propolis MeOH extract exhibited stronger DPPH free radical scavenging activity. The MeOH extracts of all propolis po ssessed stronger cytotoxicity than the corresponding water extract towards murine colon 26-L5 carcinoma and human HT-1080 fibrosarcoma cells. The resu lt of hepatoprotective activity of Brazilian propolis on D-galactosamine (D -GalN)/tumor necrosis factor-alpha (TNF-alpha)-induced cell death in primar y cultured mouse hepatocytes were found in accordance with the grade set up by beekeepers in Brazil. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.