Galbanum is the greenest smell in perfumery, sharp enough to be genuinely startling. It is a gum resin tapped from a Persian Ferula, a relative of giant fennel. Beta-pinene can be three fifths of the oil, with trace pyrazines supplying that raw green-pepper bite. In lab tests the oil held back bacteria, tested against a dental disinfectant as the comparison.^[1] A single drop lifts a whole blend, and more than a drop takes it over completely.