Dr. Duke's Phytochemical and Ethnobotanical Databases. Chemical ecology in plants mainly involves plants fighting herbivory by producing various phytochemical compounds. Phytochemical and nutrient content appears to vary across mango cultivars. The main cause of phytochemical loss from cooking is thermal decomposition. Hydroxytyrosol is a phenylethanoid, a type of phenolic phytochemical with antioxidant properties in vitro. The genus of plants contains the phytochemical ephedrine. Phloridzin is a phytochemical that belongs to the class of polyphenols. Linalyl acetate is a naturally occurring phytochemical found in many flowers and spice plants. He developed the Dr. Duke's Phytochemical and Ethnobotanical Databases at the USDA. The current Phytochemical and Ethnobotanical databases facilitate plant, chemical, bioactivity, and ethnobotany searches. His thesis involved phytochemical studies of neoflavonoids and isoflavonoids. The errant batch of "Aristolochia" was later confirmed via phytochemical analysis. Major classes of phytochemical include phenols, polyphenols, tannins, terpenes, and alkaloids. One of the monolignols, it is a phytochemical synthesized via the phenylpropanoid biochemical pathway. Phytochemical tests showed the presence of terpenoids in the crude extracts.