The said
extracts of R. rosifolius and R. racemosus inhibited COX-1 by 33 and
30%, respectively. The EtOAc extracts of R. jamaicensis and R.
rosifolius also demonstrated some COX inhibitory activity, as
shown in Fig. 4. The Michigan-grown Rubus extracts were, in
general, not COX-active, while the hexane extracts of the Jamaican
spp. were the most active. The MeOH extracts showed no activity
at the concentration tested. Considering that the inhibition of COX-
2 is an indication of possible anticancer properties, it was expected
that the latter extracts would possess the highest anticancer
potential, and this is what was observed.