Quillaja: A plant genus of the family ROSACEAE whose members produce SAPONINS.Quillaja Saponins: Natural detergents made up of a heterogeneous mixture of molecules having a triterpenoid core structure. They vary in aglycone (sapogenin) and sugar moieties, including glucose.Saponins: A type of glycoside widely distributed in plants. Each consists of a sapogenin as the aglycone moiety, and a sugar. The sapogenin may be a steroid or a triterpene and the sugar may be glucose, galactose, a pentose, or a methylpentose.Polygalaceae: A plant family of the order Polygalales, subclass Rosidae, class Magnoliopsida.Saponaria: A plant species of the family CARYOPHYLLACEAE. It is a source of SAPONINS. The common name "Soapwort" is also used with VACCARIA. The common name of "Bouncing Bet" is occasionally used with VIOLA.Sapogenins: The aglucon moiety of a saponin molecule. It may be triterpenoid or steroid, usually spirostan, in nature.Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Adjuvants, Immunologic: Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.