Staining Interactions of Bixa Orellana (Annatto) Seed Extracts with Tissues of Wistar Rats

Abstract

Introduction: Bixa orellana is an ancestral multi use plant popularly known as Achiote or lipstick tree in view of its reddish – orange dye on its seeds, Central and South American populations used these seeds to color their bodies and lips, B. orellana is the only species of Bixaceae family. Aim: The aim of this study was to stain the organs such as skin, liver, kidney, brain, intestines, and bone marrow of a wistar rats with solutions of Bixa orellana (Annatto) seed extracts. Methods: The study design was experimental research, the seeds of Bixa orellana were extracted in distilled water, absolute ethanol and acetone, using maceration methods and the fractions of the extracts were determined using column chromatography while preliminary, the solutions of the extracts were used to stain tissues listed above at varying pH to establish staining interactions of the crude extracts and fractions eluted from the column chromatography. Results: The most significant staining interaction were observed in ethanol solution of bixa extract, followed by acetone and distilled water and staining were also observed at column fraction(9-26), with background yellowish appearance in all the staining solutions which was contrast to controls (haematoxylin and eosin) stained sections and no staining reaction was observed in blood smear of wistar rat. The staining interactions of great quality was observed at pH 5.0 and 7.5, despite its staining ability it was neither superior to eosin nor a substitute to giemsa stain due to the yellowish background appearance and its complete inactivity on blood smear. Conclusion: Bixa orellana dye extracts can be grouped under compound dyes or neutral dyes due to its interaction at both pH 5.0 and 7.5 and cannot be used as substitute for Giemsa stain.