Stability of piperine in different solvents and its spectrophotometric estimation.

Spectrophotometry is the most common method used for estimating piperine in pepper products. Solvents, such as benzene and ethylene dichloride used in this process, are known to be carcinogenic, so stability of piperine in light and in other solvents such as ethanol, acetone, ethyl acetate, chloroform and cyclohexane, was determined. Protection of the dilute solution of samples (with added solvents) from light for up to 2 h, did not affect piperine stability. Considerable loss of piperine was observed upon exposure to diffused day light. It is concluded that other solvents can be used in place of benzene and ethylene dichloride for piperine estimation, provided they are protected from day light for 2 h.