piperine is the alkaloid responsible for the pungency of black pepper and and long, pepper along with chavicne (an isomer of piperine). it has also been used in some forms of traditional medicine 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. if yields salts only with strong acids.
piperine is commercially available. if desied, it may be extrected fprm black pepper using dichlormethane. the amount of piperine varies form 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 alcoholic extract of black peper, 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.