Screening for Cytotoxicity of Crude Extracts from Fruit on Leukaemia Cells in Citrus and Related Genera

Screening for Cytotoxicity of Crude Extracts from Fruit on Leukaemia Cells in Citrus and Related Genera

The present study has been undertaken to characterize availability of citrus as a medicinal plant with antineoplastic property. The crude extracts from 40 species of fruits with 12 species of the local Citrus in Cheju island were evaluated on their potential activities against mouse P388 lymphocytic leukaemia in vitro. The percent cytotoxicity varied from 25.40 to 97.94% at a concentration of 100㎍/mL. Among 40 spp., 8 species showed high toxicity more than 90% against P388 cells and Cheongkyool(C. nippokoreana) exhibited the most cytotoxicity as 97.94%(IC50=20.2㎍/mL). Nine varieties of C. junos were showed insiginicant cytotoxicity. In trifoliate orange, immature fruit was stronger than mature and peel extract showed higher cytotoxicity(IC50=18㎍/mL) than the other tissues. Hexane fraction from methanol(MeOH) extract of trifoliate orange showed highly significant inhibition of cell growth(IC50=3.9㎍/mL). In addition, its cytotoxicity increased remarkably from 3.95 to 0.40㎍/mL as exposure time lengthened. Cytotoxic activities of crude extracts were decreased considerably during a six months storage period. It was apparent that there is considerable variation in cytotoxicity, depending upon species, maturity and storage time of extracts. There was no meaningful cytotoxic difference between archicitrus and metacitrus in the genus Citrus.