Capsaicin content in chillies ( <i>Capsicum annuum</i> L., <i>Capsicum frutescen</i> s L., <i>Capsicum chinense</i> Jacq.) of Northeast India by high performance thin layer chromatography (HPTLC)

Capsaicin is the primary bioactive constituent in chillies, responsible for its incomparable pungent taste and many health advantages. In the current study, 32 samples of three different species of <i>Capsicum</i> (<i>Capsicum annuum</i> L., <i>Capsicum frutescen</i>s L., <i>Capsicum chinense</i> Jacq.) from various geographical regions in Northeast India were evaluated for their total capsaicin content by high performance thin layer chromatography (HPTLC). An excellent separation of capsaicin (<i>R_f</i> = 0.268 ± 0.02) was obtained using toluene and ethyl acetate as mobile phase at a 7:3 (<i>v/v</i>) ratio. The calibration curve was described by the equation <i>Y</i> = 5.661 × 10^-9X + 1.225 × 10^-4 with a correlation coefficient (r) of 0.99894. The percentage of capsaicin was found to range from 1.99 to 24.48% <i>w/w</i>. The linearity range for the curve for capsaicin was found 200-1000 ng per spot. The limit of detection and quantification were determined to be 45.98 and 97.70 ng, respectively. The proposed validated HPTLC method may be used for routine quality testing and quantification of capsaicin in chilli samples.