Research Journal of Pharmaceutical, Biological and Chemical Sciences
Abstract
Propolis is a complex honeybee product deposited in the beehives, where it protects the hive and its occupants from microbial infection. Propolis has several reported medical applications in view of its numerous bioactive properties. The water insoluble fraction of crude Maltese honeybee propolis was extracted in methanol. Analysis by gas chromatography – mass spectrometry (GC-MS) showed the diterpenoid totarol to be the predominant constituent in all samples. The evaporated methanol residue was dissolved in dimethyl sulphoxide (DMSO) and used for cytotoxicity testing on human cancer cell lines using standard 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assays. Results obtained show that the propolis collected from Malta has cytotoxic activity in cancer cells in vitro. However, propolis collected from different sites, only a few miles apart and at different times of the year, showed marked variations in the cytotoxicity, which correlated clearly with totarol content. This reflects the differences in the species of plants, on which the bees had foraged and indicates the importance of collection site and season of collection on the bioactivity of propolis products.peer-reviewe