#pH indicator
- Anthoxanthin — A water-soluble plant pigment belonging to the flavonoid class, possessing a white, yellowish, or cream color, present in the cellular vacuoles of many plants, flowers, and fruits (such as cauliflower, onions, or white petals). This structural organic compound modifies its spectral hue depending on the acidity of the medium, becoming intense yellow in the presence of alkaline substances, and plays an essential role in protecting plant tissues against ultraviolet radiation and in cellular oxidation processes.