Using Black Carrot Extracts as an Alternative Biological Dye for Tissue Staining

Background: Tissue staining is pivotal in histology and histopathology, shouldering a noteworthy role in identifying and classifying tissues and diseases. Due to their non-production of toxic effluents, the utilization of plant-based dyes aligns harmoniously with environmental sustainability and the well-being of laboratory personnel and the general public. Furthermore, this approach is highly cost-effective, further enhancing its appeal. Objectives: This research study explored the feasibility of staining various tissues in mice, such as the liver, kidney, intestine, and cartilage, utilizing a dye extracted from black carrots. Methods: An ethanol extract of 200 g of fresh black carrots (Daucus carota L.) was prepared using 95% ethanol saturated with two different solvents in 200 mL of distilled water. Subsequently, the prepared sections of mice tissue were immersed in the extracted dye solution for 20 minutes, followed by assessment using a light microscope. Hematoxylin-eosin staining was used as a control. Results: The dye extracted from the black carrot using alum and acetic acid successfully stained the cartilage, kidney, intestine, and liver tissues, giving them a bluish-gray coloration. Phytochemical screening further confirmed the presence of anthocyanins in the black carrot extract. Conclusion: The dye derived from black carrots exhibits natural tissue staining capabilities, making it an alternative to hematoxylin-eosin in histology and histopathology laboratories.