Kola nut (cola acuminata) extract as a substitute to histological tissue stain eosin

The application of natural dyes for staining of various biological tissues from an alternative source will decrease the expense for purchasing the synthetic dye and reduce their effects on human and environment. Therefore, the objective of this study was to investigate the extraction of natural dye from Cola nut (Cola acuminata) using various solvents and its staining property on the rat tissues. The cola nut was pulvized using pestle and mortar, 5gram was used to make 5% of aqueous extract. The rat tissues were processed for paraffin embedding technique and sectioned at 5 ?m thicknesses. The sections were stained with haematoxylin and the extracts as secondary stain. The results showed that the natural extract from Cola acuminata stained the cytoplasm of various tissues with yellowish-brown colouration. This finding suggests that Cola acuminata can be used as an alternative dye for histological staining.