Male Swiss mice were pretreated with Umbelliferone (1.0 and 2.5 mg/kg orally). One hour later they were injected with acetic acid 0.6%. Then after 10 minutes the number of writhings was recorded for 20 min. Antinociceptive activity was evaluated in terms of the percentage of contraction inhibitions. Umbelliferone showed 74% inhibition of writhing contractions and was not reversed by the opioid antagonist naloxone.

Human oral carcinoma cells (KB cells) were cultured in Dulbecco's Modified Eagle Medium supplemented with 10 % heat-inactivated fetal bovine serum, 100 U/mL of penicillin and 100 micro-g/mL of streptomycin at 37 deg-C in a humidified 5% CO2 atmosphere. KB cells were seeded in 96 well plates at a concentration of 6000 cells per plate. After 24 hours of incubation, the medium was replaced with media dosed with umbelliferone at various concentrations of 50, 100, 150, 200, 250, 300, 400 and 450mM/well. After 48 hours the drug-containing medium was replaced with 100 microL of medium containing MTT in order to determine cell viability. Cell viability was significantly decreased to 80, 72, 63 and 44% when cells were exposed to umbelliferone at concentrations of 50, 100, 150 and 200mM/ml respectively.