Methylene blue is a cationic dye with a maximum absorption of approximately 670 nm (Canens 1988). It has an array of uses and has been applied in biological sciences as a stain since the early 1900s. Often, methylene blue is used in solution as a redox indicator by changing from a blue solution to colorless when in the presence of a reducing agent (Prasetyo & Mufakhir 2011). It can also be substituted for crystal violet in the Gram staining method. It has also been used as a nuclear stain, or for differentiating pectin compounds. In plants, the protoplast and lignified walls will stain a bright blue and the pectin compounds will stain a violet blue. In diatoms and other simple organisms, Stevens (1916) suggests a 0.001% solution for staining the nuclei. Seeds can be stained using a 1% methylene blue solution to determine the anatomy of the seed (Orozco-Segovia et al. 2007).