Extracts of nine species of plants traditionally used in Colombia for the treatment of a variety of diseases were tested
in vitro for their potential antitumor (cytotoxicity) and antiherpetic activity. MTT (Tetrazolium blue) and Neutral Red colorimetric assays were used to evaluate the reduction of viability of cell cultures in presence and absence of the extracts. MTT was also used to evaluate the effects of the extracts on the lytic activity of herpes simplex virus type 2 (HSV-2). The 50% cytotoxic concentration (CC
50) and the 50% inhibitory concentration of the viral effect (EC
50) for each extract were calculated by linear regression analysis. Extracts from
Annona muricata, A. cherimolia and
Rollinia membranacea, known for their cytotoxicity were used as positive controls. Likewise, acyclovir and heparin were used as positive controls of antiherpetic activity.
Methanolic extract from
Annona sp. on HEp-2 cells presented a CC
50 value at 72 hr of 49.6x10
3μg/ml. Neither of the other extracts examined showed a significant cytotoxicity. The aqueous extract from
Beta vulgaris, the ethanol extract from
Callisia grasilis and
the methanol extract
Annona sp. showed some antiherpetic activity with acceptable therapeutic indexes (the ratio of CC
50 to EC
50). These species are good candidates for further activity-monitored fractionation to identify active principles.
