Bitter principles

Also found in: Medical.
(Chem.) a class of substances, extracted from vegetable products, having strong bitter taste but with no sharply defined chemical characteristics.

See also: Bitter

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Specific active phytochemical constituents (Flavone glycosides Megastigmane glycosides bitter principles saponine Caratuberside (A and B) Boucerosides (I to X) Tomentogenin Sitosterols Luteolin-4-neohesperidoside and Kaempferol-7-0-neohesperidosid) can be enhanced by breeding procedures.
For example, to prevent migraines we are told to eat foods containing vitamin B3, bitter principles and quercetin such as Brazil nuts, garlic, muesli, mushrooms, oats, onion, rice and sweetcorn.
Summer-harvested roots (June--August) produce a less uniform product with lower content of biologically active bitter principles. Late September--October harvest is preferred.