Quantifying Piperine in Black Pepper Samples

The piperine content of black pepper powder and gummies was measured by using a standard method [21 ]. Accurately weigh 0.5 g gummy sample (ground in pestle and mortar) and black pepper powder, transfer to a 125 mL Erlenmeyer separately, and protect from light. Add 70 mL 1,2-dichloroethane (C₂H₄C₁₂), reflux, and stir for 1 h. Extracted piperine was then cooled and filtered into a 100 mL volumetric flask. Then, pipette out 2 mL of this solution into another 100 mL volumetric flask, dilute up to the volume mark, and measure absorbance at a maximum of 345 nm using a UV spectrometer. $\begin{array}{c}\text{Piperine}\%=\frac{A_{\text{s}}\times F\times V}{W_{\text{s}}\times {10}^6}\times 100,\end{array}$ where A_s is the absorbance of sample, F is the factor derived from piperine standard, V is the dilution volume (mL), and W_s is the sample weight (g).