Influence of Erythrina crista-galli L. extract natural dye in plant histology staining

The development of the use of preparations with natural coloring has been carried out a lot, but no one shows optimal concentration. The purpose of this study was to determine the optimal concentration of Erythrina crista-galli L. flower extract as a natural dye based on the parameters of the quality and stability of the preparation. The type of research used is experimental research. This research method through several stages: extracting, diluting extracts with various concentrations (30%, 50%, 70%, 90%, and 100%), until making maceration preparations. Data collections were conducted twice, where the first and second take has an interval of one semester. Kruskal Wallis was used as a technique for analyzing data from research results. Both in the first and second observations, the concentration of 70% always produces the best quality preparations. However, the stability of natural staining was not good due to color quality was decreasing. Thus, although Erythrina crista-galli L. has a good potency, the flower extract has not recommended as natural staining.