Trigonelline is a product of niacin metabolism that is excreted in the urine of mammals.

Sakurajima Daikon), fenugreek seeds (Trigonella foenum-graecum, hence the name),[3] garden peas, hemp seed, oats,[4] potatoes, Stachys species, dahlia,[5] Strophanthus species,[6] and Dichapetalum cymosum.

The salts crystallize well, the monohydrochloride, in leaflets, sparingly soluble in dry alcohol.

The alkaloid forms several aurichlorides: the normal salt, B•HCl•AuCl3, is precipitated when excess of gold chloride is added to the hydrochloride, and, after crystallization from dilute hydrochloric acid containing some gold chloride, has m.p. 198 °C.

When trigonelline is heated in closed tubes with barium hydroxide at 120 °C, it gives rise to methylamine, and, if treated similarly with hydrochloric acid at 260 °C creates chloromethane and nicotinic acid (a form of vitamin B3).