Inhibitory effects of extracts from peels of Citrus natsudaidai encapsulated in hybrid liposomes on the growth of tumor cells in vitro.

Inhibitory effects of extracts from peels of Citrus natsudaidai (natsumikan) encapsulated in hybrid liposomes (HL) composed of L-alpha-dimyristoylphosphatidylcholine and polyoxyethylene (20) sorbitan monolaurate on the growth of tumor cells were examined. The extracts with lower polar solvents inhibited the growth of B-16 mouse melanoma and human lung carcinoma cells, although the extracts with higher polar solvents showed no antitumor activity. In particular, the inhibitory effects of extracts with lower polar solvents encapsulated in HL were enhanced as compared with those of free extracts.