piperine
piperine is the alkaloid responsible for the pungency of black pepper and long pepper along with chavicine ( an isomer of piperine ). lt has also been used in some forms of traditional medicinal and as an insecticide.piperine forms monoclinic needles is slightly soluble in water and more so in alcohol ether or chloroform the solution in alcohol has a pepper-like taste it yields salts only with strong acids .
piperine is commercially available . if desired, it may be extracted from black pepper using dichloromethane. the amount of piperine varies from 1-2 % in long pepper, to 5-9% in the white and the black peppers of commerce . further, it may be prepared by treating the solvent-free residue from an alcohol extract of black pepper , with a solution of sodium hydroxide to remove resin (said to contain chavicine, an isomer of piperine) and solution of the washed, insoluble residue in warm alcohol, from which the alkaloid crystallises on cooling